{"id":168460,"date":"2026-07-28T14:16:59","date_gmt":"2026-07-28T14:16:59","guid":{"rendered":"https:\/\/pabau.com\/?p=168460"},"modified":"2026-08-17T11:38:13","modified_gmt":"2026-08-17T11:38:13","slug":"cpt-code-00635","status":"publish","type":"post","link":"https:\/\/pabau.com\/fr\/procedure-codes\/cpt-code-00635\/","title":{"rendered":"CPT Code 00635: Anesthesia for lumbar puncture billing guide"},"content":{"rendered":"\n<script type=\"application\/ld+json\">{\"@context\":\"https:\/\/schema.org\",\"@type\":\"MedicalWebPage\",\"headline\":\"CPT Code 00635: Anesthesia for lumbar puncture billing guide\",\"description\":\"CPT Code 00635 covers anesthesia for diagnostic or therapeutic lumbar puncture. Learn base units, modifiers, Medicare rates, ICD-10 crosswalk, and documentation requirements.\",\"url\":\"https:\/\/pabau.com\/procedure-codes\/cpt-code-00635\/\",\"audience\":{\"@type\":\"MedicalAudience\",\"audienceType\":\"Clinician\"},\"reviewedBy\":{\"@type\":\"Person\",\"name\":\"Dr Vanja Kitanova\",\"jobTitle\":\"Medical Reviewer\",\"affiliation\":{\"@type\":\"Organization\",\"name\":\"Pabau\"},\"knowsAbout\":[\"Medical Coding\",\"Clinical Documentation\",\"Healthcare Billing\",\"Clinical Safety\"],\"sameAs\":\"https:\/\/pabau.com\/blog\/author\/vanja\/\"},\"datePublished\":\"2026-07-28\",\"dateModified\":\"2026-07-28\"}<\/script>\n\n\n        <div id=\"key_takeaways\">\n            <div class=\"header\">\n                                    <img decoding=\"async\" src=\"https:\/\/pabau.com\/wp-content\/uploads\/2025\/12\/Key-Takeaways-Icon.svg\" alt=\"Key takeaways\" height=\"42\" width=\"42\">\n                                <h3>Key takeaways<\/h3>\n            <\/div>\n            <div class=\"list\">\n                                                            <div class=\"item\">\n                            <div>\n                                <svg width=\"20\" height=\"27\" viewBox=\"0 0 20 27\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">\n                                    <path\n                                        d=\"M18.6223 14.3857C19.1246 13.8975 19.1246 13.1045 18.6223 12.6162L12.1938 6.36621C11.6915 5.87793 10.8759 5.87793 10.3737 6.36621C9.87143 6.85449 9.87143 7.64746 10.3737 8.13574L14.6125 12.2529H2.28571C1.57455 12.2529 1 12.8115 1 13.5029C1 14.1943 1.57455 14.7529 2.28571 14.7529H14.6085L10.3777 18.8701C9.87545 19.3584 9.87545 20.1514 10.3777 20.6396C10.8799 21.1279 11.6955 21.1279 12.1978 20.6396L18.6263 14.3896L18.6223 14.3857Z\"\n                                        fill=\"#3D3D46\" \/>\n                                <\/svg>\n                            <\/div>\n                            <p>CPT Code 00635 reports anesthesia services for diagnostic or therapeutic lumbar puncture procedures under the spine and spinal cord anesthesia section.<\/p>\n                        <\/div>\n                                                                                <div class=\"item\">\n                            <div>\n                                <svg width=\"20\" height=\"27\" viewBox=\"0 0 20 27\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">\n                                    <path\n                                        d=\"M18.6223 14.3857C19.1246 13.8975 19.1246 13.1045 18.6223 12.6162L12.1938 6.36621C11.6915 5.87793 10.8759 5.87793 10.3737 6.36621C9.87143 6.85449 9.87143 7.64746 10.3737 8.13574L14.6125 12.2529H2.28571C1.57455 12.2529 1 12.8115 1 13.5029C1 14.1943 1.57455 14.7529 2.28571 14.7529H14.6085L10.3777 18.8701C9.87545 19.3584 9.87545 20.1514 10.3777 20.6396C10.8799 21.1279 11.6955 21.1279 12.1978 20.6396L18.6263 14.3896L18.6223 14.3857Z\"\n                                        fill=\"#3D3D46\" \/>\n                                <\/svg>\n                            <\/div>\n                            <p>The code carries 4 ASA-assigned base units. Medicare pays base units plus time units, while ASA RVG and commercial-payer formulas may also add physical status modifier units before applying the conversion factor.<\/p>\n                        <\/div>\n                                                                                <div class=\"item\">\n                            <div>\n                                <svg width=\"20\" height=\"27\" viewBox=\"0 0 20 27\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">\n                                    <path\n                                        d=\"M18.6223 14.3857C19.1246 13.8975 19.1246 13.1045 18.6223 12.6162L12.1938 6.36621C11.6915 5.87793 10.8759 5.87793 10.3737 6.36621C9.87143 6.85449 9.87143 7.64746 10.3737 8.13574L14.6125 12.2529H2.28571C1.57455 12.2529 1 12.8115 1 13.5029C1 14.1943 1.57455 14.7529 2.28571 14.7529H14.6085L10.3777 18.8701C9.87545 19.3584 9.87545 20.1514 10.3777 20.6396C10.8799 21.1279 11.6955 21.1279 12.1978 20.6396L18.6263 14.3896L18.6223 14.3857Z\"\n                                        fill=\"#3D3D46\" \/>\n                                <\/svg>\n                            <\/div>\n                            <p>Missing or incorrect modifiers (AA, QK, QS, P-modifiers) are the most common reason claims for CPT Code 00635 are denied.<\/p>\n                        <\/div>\n                                                                                <div class=\"item\">\n                            <div>\n                                <svg width=\"20\" height=\"27\" viewBox=\"0 0 20 27\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">\n                                    <path\n                                        d=\"M18.6223 14.3857C19.1246 13.8975 19.1246 13.1045 18.6223 12.6162L12.1938 6.36621C11.6915 5.87793 10.8759 5.87793 10.3737 6.36621C9.87143 6.85449 9.87143 7.64746 10.3737 8.13574L14.6125 12.2529H2.28571C1.57455 12.2529 1 12.8115 1 13.5029C1 14.1943 1.57455 14.7529 2.28571 14.7529H14.6085L10.3777 18.8701C9.87545 19.3584 9.87545 20.1514 10.3777 20.6396C10.8799 21.1279 11.6955 21.1279 12.1978 20.6396L18.6263 14.3896L18.6223 14.3857Z\"\n                                        fill=\"#3D3D46\" \/>\n                                <\/svg>\n                            <\/div>\n                            <p>Practice management software like Pabau captures structured pre-anesthesia intake data and keeps clinical documentation tied to the patient record, supporting the audit-ready recordkeeping anesthesia billing requires.<\/p>\n                        <\/div>\n                                                <\/div>\n        <\/div>\n    \n\n\n<p class=\"wp-block-paragraph\">CPT Code 00635 reports anesthesia for diagnostic or therapeutic lumbar puncture. It carries its own base unit value, modifier requirements, and documentation standards, distinct from other spinal anesthesia codes. Getting the descriptor, base units, and modifiers right from the first submission is what keeps a claim out of the rework queue.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This guide covers the official code descriptor, the base units and reimbursement formula, and the modifiers required on every claim. It also walks through Medicare fee schedule context and the ICD-10 codes that support medical necessity. It closes with the documentation anesthesia billing teams need to keep on file.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">CPT Code 00635: definition and clinical description<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Anesthesia claims for lumbar puncture generate a disproportionate share of modifier-related denials. CPT Code 00635 is the correct reporting code when an anesthesia provider administers anesthesia for a diagnostic or therapeutic lumbar puncture. Getting the modifiers and documentation right from the start keeps the claim out of a multi-week rework cycle.<\/p>\n\n\n\n<figure class=\"wp-block-embed is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio\">\n<div class=\"wp-block-embed__wrapper\">\n<iframe title=\"CPT Coding Pitfalls Every Medical Practice Faces\" width=\"800\" height=\"450\" src=\"https:\/\/www.youtube.com\/embed\/vbvV5okdXKg?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe>\n<\/div>\n<\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">According to the <a href=\"https:\/\/www.ama-assn.org\/practice-management\/cpt\/cpt-code-set-overview\" target=\"_blank\" rel=\"nofollow noopener\">American Medical Association (AMA)<\/a>, CPT Code 00635 falls within the anesthesia section covering procedures on the spine and spinal cord. The official code description reads: <strong>Anesthesia for procedures in lumbar region; diagnostic or therapeutic lumbar puncture.<\/strong> Both diagnostic and therapeutic lumbar punctures fall under this single code. Diagnostic lumbar punctures are spinal taps performed to analyze cerebrospinal fluid, while therapeutic punctures relieve elevated intracranial pressure. The procedure may be performed by a physician anesthesiologist or a Certified Registered Nurse Anesthetist (CRNA), each billing with different modifier sets.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">CPT Code 00635 sits in the parent code grouping for lumbar region anesthesia, alongside adjacent codes 00630 and 00640. Coders should confirm the specific procedure documented before selecting among this family. Lumbar puncture has its own dedicated code rather than mapping to adjacent spinal anesthesia codes.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Anesthesia base units and the reimbursement formula for CPT 00635<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Anesthesia reimbursement does not work like standard fee-for-service codes. Medicare&rsquo;s formula combines base units assigned by the American Society of Anesthesiologists (ASA) with time units based on intraoperative duration. ASA RVG and most commercial-payer formulas add a third component: physical status modifier units that reflect patient complexity. The same three-part formula applies across the anesthesia code family.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>CPT Code 00635 carries 4 ASA-assigned base units.<\/strong> Medicare and most commercial payers calculate the payment differently, so the two formulas below are not interchangeable:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Medicare (CMS):<\/strong> Total Units = Base Units (4) + Time Units<br>Payment = Total Units \u00d7 Medicare Anesthesia Conversion Factor<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>ASA RVG \/ commercial payers:<\/strong> Total Units = Base Units (4) + Time Units + Physical Status Modifier Units<br>Payment = Total Units \u00d7 payer&rsquo;s conversion factor<\/p>\n\n\n\n<table style=\"width:100%;border-collapse:separate;border-spacing:0;border-radius:12px;overflow:hidden;font-size:15px;line-height:1.5;margin:1.5em 0 2em;box-shadow:0 2px 12px rgba(0,0,0,0.08)\">\n<thead>\n<tr>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">Component<\/th>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">Value \/ Rule<\/th>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">Notes<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">Base units<\/td>\n<td style=\"padding:12px 16px;color:#374151\">4<\/td>\n<td style=\"padding:12px 16px;color:#374151\">ASA-assigned; fixed for 00635<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">Time units<\/td>\n<td style=\"padding:12px 16px;color:#374151\">1 unit per 15 minutes<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Round to nearest 15-min increment; document start and stop time<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">Physical status units<\/td>\n<td style=\"padding:12px 16px;color:#374151\">P1 = 0; P2 = 0; P3 = 1; P4 = 2; P5 = 3<\/td>\n<td style=\"padding:12px 16px;color:#374151\">ASA RVG \/ commercial payers only, not paid by Medicare; P6 (brain-dead organ donor) = 0; P1-P2 add no units but modifier still required<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">Conversion factor (2026)<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Varies by locality<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Verify current year rate via the <a href=\"https:\/\/www.cms.gov\/medicare\/physician-fee-schedule\/search\/overview\" target=\"_blank\" rel=\"nofollow noopener\">CMS fee schedule lookup<\/a><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n\n\n\n<p class=\"wp-block-paragraph\">Time units are the variable in every anesthesia claim. A 30-minute lumbar puncture generates 2 time units. A 45-minute procedure generates 3. Documenting start and stop times precisely is not optional. It is the primary audit trigger when time unit calculations look inconsistent with procedure complexity.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Modifiers used with CPT Code 00635<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Anesthesia codes require modifiers that other CPT families do not. Two distinct modifier types apply to CPT Code 00635. Provider-role modifiers identify who administered the anesthesia and how, while physical status modifiers describe the patient&rsquo;s preoperative health classification. Both types are required on every claim.<\/p>\n\n\n\n<table style=\"width:100%;border-collapse:separate;border-spacing:0;border-radius:12px;overflow:hidden;font-size:15px;line-height:1.5;margin:1.5em 0 2em;box-shadow:0 2px 12px rgba(0,0,0,0.08)\">\n<thead>\n<tr>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">Modifier<\/th>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">Meaning<\/th>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">When to use<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">AA<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Anesthesia personally performed by anesthesiologist<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Physician anesthesiologist performs the entire case without a CRNA or resident<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">QK<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Medical direction of 2-4 concurrent cases<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Anesthesiologist directing multiple CRNAs or residents simultaneously<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">QX<\/td>\n<td style=\"padding:12px 16px;color:#374151\">CRNA under medical direction<\/td>\n<td style=\"padding:12px 16px;color:#374151\">CRNA billing when the case is medically directed by a physician<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">QZ<\/td>\n<td style=\"padding:12px 16px;color:#374151\">CRNA without medical direction<\/td>\n<td style=\"padding:12px 16px;color:#374151\">CRNA billing independently (opt-out states); verify state supervision rules before using<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">QS<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Monitored anesthesia care (MAC)<\/td>\n<td style=\"padding:12px 16px;color:#374151\">When lumbar puncture is performed under MAC rather than general anesthesia<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">P1-P6<\/td>\n<td style=\"padding:12px 16px;color:#374151\">ASA physical status classification<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Required on every anesthesia claim; reflects patient&rsquo;s systemic health status<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n\n\n\n<p class=\"wp-block-paragraph\">CRNA billing rules for CPT Code 00635 vary by state supervision requirement and payer policy. Depending on the state and payer contract, a CRNA may bill independently (QZ) or must bill under medical direction (QX). Always verify the applicable supervision rules before submitting. Incorrect modifier pairing is a common audit trigger for anesthesia claims.<\/p>\n\n\n        <div id=\"pro_tip\">\n            <div class=\"img\">\n                <svg width=\"42\" height=\"42\" viewBox=\"0 0 42 42\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">\n                    <path fill-rule=\"evenodd\" clip-rule=\"evenodd\"\n                        d=\"M12.6383 19.5238C12.6632 21.2071 12.8734 22.9926 12.0685 24.5523C11.0341 26.8917 8.45076 28.169 7.56292 30.5918C6.63082 33.1061 7.19505 36.185 9.31371 37.9786C10.929 39.5678 13.4183 39.9873 15.6061 39.5463C17.4592 39.073 19.1049 37.8388 19.9706 36.1608C20.781 34.7141 20.7866 32.9904 20.5293 31.3985C20.1006 29.3092 18.3775 27.8705 16.9807 26.362C14.8814 24.1005 14.6684 20.6854 15.595 17.8915C16.4331 15.4768 19.0026 14.2344 20.0425 11.9461C20.7202 10.6769 20.7506 9.20327 20.6068 7.81304C20.1864 5.40098 18.3139 3.23631 15.8716 2.56674C13.9742 2.03969 11.8224 2.30052 10.1739 3.37614C8.70522 4.34688 7.5878 5.86618 7.28356 7.58178C6.76081 9.82981 7.53525 12.2822 9.20307 13.9118C10.7658 15.4741 12.4806 17.2273 12.6383 19.5238Z\"\n                        fill=\"#2BADD4\" \/>\n                    <path fill-rule=\"evenodd\" clip-rule=\"evenodd\"\n                        d=\"M22.7048 19.8387C22.6822 22.3279 24.4507 24.6234 26.7493 25.4682C28.0531 25.961 29.4725 25.9183 30.7989 25.5487C32.0575 24.9955 33.301 24.2237 34.0069 23.0092C34.8384 21.5811 35.2982 19.8286 34.7832 18.2094C34.3611 16.2507 32.8739 14.6541 31.0275 13.9426C28.6736 12.9595 25.8073 13.7942 24.1719 15.7001C23.2022 16.8366 22.6143 18.3326 22.7048 19.8387Z\"\n                        fill=\"#2BADD4\" \/>\n                <\/svg>\n            <\/div>\n            <div class=\"text\">\n                <h3>Pro Tip<\/h3>\n                <p>Always append both a provider-role modifier (AA, QK, QX, or QZ) and a physical status modifier (P1-P6) on every CPT Code 00635 claim. A claim missing either type will typically reject at the clearinghouse before it reaches the payer, requiring a full resubmission.<\/p>\n            <\/div>\n        <\/div>\n    \n\n\n<p class=\"wp-block-paragraph\">Comparing <a href=\"https:\/\/pabau.com\/blog\/best-medical-practice-management-software\/\">practice management systems for medical teams<\/a> is worth the effort before anesthesia time-unit billing becomes a spreadsheet job.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Medicare reimbursement and fee schedule for CPT Code 00635 (2026)<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Medicare pays anesthesia using the base plus time formula with a geographically adjusted conversion factor. National average rates for CPT Code 00635 vary by locality. Confirm 2026 rates directly through the CMS fee schedule tool, since CMS updates conversion factors annually.<\/p>\n\n\n\n<table style=\"width:100%;border-collapse:separate;border-spacing:0;border-radius:12px;overflow:hidden;font-size:15px;line-height:1.5;margin:1.5em 0 2em;box-shadow:0 2px 12px rgba(0,0,0,0.08)\">\n<thead>\n<tr>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">Rate type<\/th>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">Description<\/th>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">Notes<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">Medicare facility rate<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Paid when service is rendered in a hospital or ASC<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Practice expense component is lower; facility bills separately for overhead<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">Non-facility rate<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Paid when service is rendered in office setting<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Higher rate; includes practice expense; less common for lumbar puncture anesthesia<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">Geographic adjustment<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Locality-based multiplier applied to base conversion factor<\/td>\n<td style=\"padding:12px 16px;color:#374151\">High-cost localities (e.g., Manhattan) pay materially more than rural areas<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">Commercial payer rates<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Contract-dependent; typically 100-150% of Medicare<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Verify against your payer contract; rates are not publicly standardized<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n\n\n\n<p class=\"wp-block-paragraph\">Use the <a href=\"https:\/\/fastrvu.com\/tools\/rvu-lookup\" target=\"_blank\" rel=\"nofollow noopener\">FastRVU RVU lookup tool<\/a> to calculate locality-specific payment estimates for CPT Code 00635. Commercial payer rates are contract-dependent and should be confirmed against the individual payer agreement rather than assumed to track Medicare.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">ICD-10 codes that support medical necessity for CPT Code 00635<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Every CPT Code 00635 claim requires a paired ICD-10 diagnosis code. Payers use this pairing to confirm the procedure was clinically indicated. The ICD-10 code should reflect the underlying condition that made the lumbar puncture necessary, not the procedure itself.<\/p>\n\n\n\n<table style=\"width:100%;border-collapse:separate;border-spacing:0;border-radius:12px;overflow:hidden;font-size:15px;line-height:1.5;margin:1.5em 0 2em;box-shadow:0 2px 12px rgba(0,0,0,0.08)\">\n<thead>\n<tr>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">ICD-10-CM Code<\/th>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">Description<\/th>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">Context<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">G03.9<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Meningitis, unspecified<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Diagnostic puncture to rule out or confirm meningitis<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">G93.2<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Benign intracranial hypertension<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Therapeutic puncture to relieve elevated CSF pressure<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">R51.9<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Headache, unspecified<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Workup for subarachnoid hemorrhage or thunderclap headache; pair with more specific code when available<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">A87.9<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Viral meningitis, unspecified<\/td>\n<td style=\"padding:12px 16px;color:#374151\">CSF analysis for suspected viral CNS infection<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">C79.32<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Secondary malignant neoplasm of cerebral meninges<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Diagnostic or therapeutic puncture in oncology patients<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">G35<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Multiple sclerosis<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Diagnostic puncture for oligoclonal band analysis<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n\n\n\n<p class=\"wp-block-paragraph\">Use the most specific ICD-10-CM code available. Unspecified codes (R51.9, G03.9) increase denial risk because payers may question whether documentation supports the level of clinical complexity billed. When the clinical picture supports a more specific code, always use it. Cross-referencing related codes.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Documentation requirements for CPT Code 00635<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Incomplete anesthesia records are the second most common reason CPT Code 00635 claims are flagged in post-payment audits. Good HIPAA-compliant documentation practices require maintaining a complete anesthesia record that satisfies both the payer and any subsequent audit review. Anesthesia carries meaningful liability exposure. Every element below should be present in the anesthesia record before the claim is submitted.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Pre-anesthesia evaluation:<\/strong> documented assessment of the patient&rsquo;s airway, allergies, current medications, and ASA physical status classification (P1-P6) performed before the procedure begins<\/li>\n<li><strong>Anesthesia start and stop times:<\/strong> recorded to the minute. Time units are calculated from these entries and directly determine reimbursement<\/li>\n<li><strong>Provider type and role:<\/strong> whether the case was performed by a physician anesthesiologist, CRNA under direction, or CRNA independently. This drives modifier selection<\/li>\n<li><strong>Intraoperative monitoring record:<\/strong> continuous vital sign documentation at regular intervals throughout the procedure<\/li>\n<li><strong>Anesthetic agents used:<\/strong> agents, doses, and routes of administration recorded in the anesthesia record<\/li>\n<li><strong>Post-anesthesia note:<\/strong> brief note confirming the patient&rsquo;s status and condition at transfer from anesthesia care. Required for MAC cases under CMS guidelines<\/li>\n<li><strong>Medical necessity statement:<\/strong> the reason anesthesia was required for this specific lumbar puncture should be clear from the clinical record. This matters most for MAC cases, where payers may question necessity versus moderate sedation<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">The patient record documentation must be retrievable for up to 7 years under Medicare rules. Storing records in a format that can be exported quickly for payer requests reduces audit response time significantly.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/cdn.pabau.com\/cdn\/attachments\/pulse\/content-engine\/billing_codes\/cpt-code-00635\/comprehensive-patient-records.webp\" alt=\"Comprehensive patient records\"\/><figcaption class=\"wp-element-caption\"><em>Pabau&rsquo;s patient records feature keeps every element of the anesthesia note together, supporting the audit-ready documentation CPT Code 00635 claims require.<\/em><\/figcaption><\/figure>\n\n\n\n<div style=\"height:35px;width:800px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n\n\n<h2 class=\"wp-block-heading\">Monitored anesthesia care (MAC) and CPT Code 00635<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Lumbar puncture is frequently performed under monitored anesthesia care rather than general anesthesia. When MAC is the method used, modifier QS must be appended to CPT Code 00635. CMS covers MAC for lumbar puncture when the patient&rsquo;s clinical condition makes general or regional anesthesia risky. It also applies when the procedure requires monitoring beyond moderate sedation. Outpatient settings such as infusion centers face the same MAC documentation standard for their own procedures.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The key documentation requirement for MAC cases is demonstrating why moderate sedation was insufficient. A MAC claim without a clinical justification for anesthesia involvement is the most common source of MAC-specific denials. Document the complicating clinical factors (patient anxiety, inability to remain still, prior adverse reactions to sedation) in the pre-anesthesia evaluation note.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Billing tips and common denial reasons for CPT Code 00635<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Most CPT Code 00635 denials fall into a small number of categories. Addressing these systematically before submission eliminates the majority of rework.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Missing provider-role modifier:<\/strong> submitting 00635 without AA, QK, QX, or QZ is the single most common rejection reason. Clearinghouses often reject the claim before it reaches the payer<\/li>\n<li><strong>Missing physical status modifier:<\/strong> P-modifiers are required even for P1 and P2 patients, who add zero units. The absence of the modifier, not the unit value, triggers the rejection<\/li>\n<li><strong>Incorrect time unit calculation:<\/strong> rounding errors or a wrong start\/stop time source create unit mismatches that trigger post-payment audits. The wrong source is often clock time instead of the time recorded in the anesthesia record<\/li>\n<li><strong>Wrong place of service code:<\/strong> facility and non-facility rates differ. A mismatch between the claim&rsquo;s place-of-service code and where the procedure occurred causes payment at the wrong rate, or an outright denial<\/li>\n<li><strong>Insufficient medical necessity documentation:<\/strong> claims with unspecified ICD-10 codes that cannot be linked to the procedure context are frequently returned for additional documentation<\/li>\n<li><strong>MAC without clinical justification:<\/strong> QS modifier claims require supporting documentation that moderate sedation was clinically insufficient. Absence of this note is an audit target<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Review CPT Code 00635 denial patterns across providers quarterly. A single coder habit, such as consistently rounding time units incorrectly, can generate a denial pattern. Payers often flag that pattern in post-payment audits before the practice catches it internally. Track denial reasons by modifier type to isolate where errors cluster.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Related CPT codes for lumbar puncture and spinal anesthesia<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">CPT Code 00635 is the correct code specifically for anesthesia during lumbar puncture. Several adjacent codes in the same family apply to related spinal and lumbar procedures. Understanding the distinctions prevents unbundling errors and ensures the correct code is selected when documentation describes a different procedure than lumbar puncture.<\/p>\n\n\n\n<table style=\"width:100%;border-collapse:separate;border-spacing:0;border-radius:12px;overflow:hidden;font-size:15px;line-height:1.5;margin:1.5em 0 2em;box-shadow:0 2px 12px rgba(0,0,0,0.08)\">\n<thead>\n<tr>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">CPT Code<\/th>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">Description<\/th>\n<th style=\"background:#121D36;color:#fff;padding:14px 16px;text-align:left;font-weight:600;font-size:14px;letter-spacing:0.3px;border-bottom:2px solid #2BADD4\">Key distinction from 00635<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">00630<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Anesthesia for procedures in lumbar region not otherwise specified<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Catch-all for lumbar procedures; 00635 is the specific code when lumbar puncture is documented<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\"><a href=\"https:\/\/pabau.com\/procedure-codes\/cpt-code-00640\/\" rel=\"noopener\">00640<\/a><\/td>\n<td style=\"padding:12px 16px;color:#374151\">Anesthesia for manipulation of the spine or for closed procedures on the cervical, thoracic, or lumbar spine<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Covers spinal manipulation and closed procedures at any spinal level, not lumbar puncture<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">00604<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Anesthesia for procedures on cervical spine and cord; procedures with patient in the sitting position (13 base units)<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Cervical level, sitting-position procedures only; unrelated to lumbar puncture despite the nearby code number<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0;background:#F9FAFB\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">62270<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Spinal puncture, lumbar, diagnostic<\/td>\n<td style=\"padding:12px 16px;color:#374151\">The surgical\/procedural code for the lumbar puncture itself; 00635 is the anesthesia companion code<\/td>\n<\/tr>\n<tr style=\"border-bottom:1px solid #E8ECF0\">\n<td style=\"padding:12px 16px;font-weight:600;color:#121D36\">62272<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Spinal puncture, therapeutic, for drainage of CSF<\/td>\n<td style=\"padding:12px 16px;color:#374151\">Therapeutic drainage version of the procedure; 00635 remains the correct anesthesia code when this is performed<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n\n\n\n<p class=\"wp-block-paragraph\">Coders sometimes mistakenly bill 00630 when 00635 is clearly documented. CPT 00635 is the more specific code and carries its own base unit value. Using the catch-all 00630 when lumbar puncture is documented constitutes incorrect coding. The same principle applies to less common codes like 00796, reported for liver transplant anesthesia. For other specialty CPT codes in procedure-specific anesthesia contexts, always confirm the most specific available code before falling back to a category-level code.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">How practice management software supports anesthesia billing workflows<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Most 00635 billing errors, missing modifiers, incorrect time units, and incomplete documentation, come from workflow breakdowns rather than coder mistakes. When clinical documentation and billing happen in separate systems, the information required to build a clean claim gets lost or misrecorded in the handoff.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Practice management software like Pabau centers pre-anesthesia documentation in the patient record instead of a separate system. Structured intake and consent forms capture the airway assessment, allergy history, current medications, and ASA physical status classification consistently across every case. Clinical documentation and treatment notes sit in the same patient record as the intake data. Anesthesia start and stop times and the agents administered no longer move between a paper chart and a separate billing system.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img fetchpriority=\"high\" decoding=\"async\" width=\"1047\" height=\"770\" src=\"https:\/\/pabau.com\/wp-content\/uploads\/2026\/07\/One-dashboard-for-all-your-insurance-claims.png\" alt=\"Insurance claim details showing payer, claim amount, and paid amount\" class=\"wp-image-160653\" srcset=\"https:\/\/pabau.com\/wp-content\/uploads\/2026\/07\/One-dashboard-for-all-your-insurance-claims.png 1047w, https:\/\/pabau.com\/wp-content\/uploads\/2026\/07\/One-dashboard-for-all-your-insurance-claims-300x221.png 300w, https:\/\/pabau.com\/wp-content\/uploads\/2026\/07\/One-dashboard-for-all-your-insurance-claims-1024x753.png 1024w, https:\/\/pabau.com\/wp-content\/uploads\/2026\/07\/One-dashboard-for-all-your-insurance-claims-768x565.png 768w\" sizes=\"(max-width: 1047px) 100vw, 1047px\" \/><figcaption class=\"wp-element-caption\"><em>Pabau&rsquo;s claims dashboard tracks payer, claim amount, and paid amount together, so anesthesia billing teams can verify a CPT Code 00635 claim before submission.<\/em><\/figcaption><\/figure>\n\n\n\n<div style=\"height:35px;width:800px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n\n\n<p class=\"wp-block-paragraph\">For practices managing several anesthesia providers, keeping every provider&rsquo;s documentation in one record makes missing information easier to catch before a claim goes out. Digital intake forms capture pre-anesthesia evaluation data in a structured format. The physical status classification, allergy documentation, and risk factors that feed into modifier selection are recorded consistently across every case.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img decoding=\"async\" src=\"https:\/\/cdn.pabau.com\/cdn\/attachments\/pulse\/content-engine\/billing_codes\/cpt-code-00635\/customizable-consent-and-intake-forms.webp\" alt=\"Customizable consent and intake forms\"\/><figcaption class=\"wp-element-caption\"><em>Pabau&rsquo;s customizable intake and consent forms capture ASA physical status, allergies, and pre-anesthesia history in the same structured format for every CPT Code 00635 case.<\/em><\/figcaption><\/figure>\n\n\n\n<div style=\"height:35px;width:800px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n\n\n<p class=\"wp-block-paragraph\">Practice management tools like Pabau also support the audit-ready recordkeeping that anesthesia billing requires. Anesthesia records are retrievable in exportable formats, supporting rapid response to payer documentation requests. For practices building or auditing their clinical compliance workflows, integrating documentation and billing into a single platform removes the manual reconciliation step. That step creates most claim errors. See how practices using integrated practice management reduce administrative rework across their billing cycles.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Related CPT codes<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li><a href=\"https:\/\/pabau.com\/procedure-codes\/cpt-code-00731\/\">CPT code 00731 \u2014 Anesthesia billing for upper GI endoscopy<\/a><\/li>\n\n\n<li><a href=\"https:\/\/pabau.com\/procedure-codes\/cpt-code-00670\/\">CPT code 00670 \u2014 Base units, modifiers, and<\/a><\/li>\n\n\n<li><a href=\"https:\/\/pabau.com\/procedure-codes\/cpt-code-00700\/\">CPT code 00700 \u2014 Anesthesia for upper anterior abdominal wall<\/a><\/li>\n<\/ul>\n\n\n        <div id=\"book_a_demo\">\n            <div class=\"left-side\">\n                <div class=\"logo\">\n                    <img decoding=\"async\"\n                        src=\"https:\/\/pabau.com\/wp-content\/uploads\/2026\/01\/Logo.svg\"\n                        alt=\"Logo\"\n                        loading=\"lazy\"\n                    \/>\n                <\/div>\n\n                <h3 class=\"heading\">\n                    Capture consistent pre-anesthesia documentation                <\/h3>\n\n                <p class=\"description\">\n                    Pabau&rsquo;s digital intake and consent forms capture pre-anesthesia evaluation data consistently, and clinical notes stay tied to the patient record for audit-ready documentation.                <\/p>\n\n                <div class=\"button-group\">\n                    <a href=\"\/book-demo\/\" class=\"btn btn-scale-effect btn-cta-color btn-md\">\n                        <span class=\"btn-text\">Book a demo<\/span>\n                        <div class=\"btn-icon btn-icon-right\" aria-hidden=\"true\">\n                            <svg\n                                width=\"14\"\n                                height=\"12\"\n                                viewBox=\"0 0 14 12\"\n                                fill=\"none\"\n                                xmlns=\"http:\/\/www.w3.org\/2000\/svg\"\n                            >\n                                <path\n                                    d=\"M0.75 4.77295C0.335786 4.77295 0 5.10874 0 5.52295C0 5.93716 0.335786 6.27295 0.75 6.27295V5.52295V4.77295ZM13.2803 6.05328C13.5732 5.76039 13.5732 5.28551 13.2803 4.99262L8.50736 0.219648C8.21447 -0.073245 7.73959 -0.073245 7.4467 0.219648C7.15381 0.512542 7.15381 0.987415 7.4467 1.28031L11.6893 5.52295L7.4467 9.76559C7.15381 10.0585 7.15381 10.5334 7.4467 10.8263C7.73959 11.1191 8.21447 11.1191 8.50736 10.8263L13.2803 6.05328ZM0.75 5.52295V6.27295L12.75 6.27295V5.52295V4.77295L0.75 4.77295V5.52295Z\"\n                                    fill=\"currentColor\"\n                                ><\/path>\n                            <\/svg>\n                        <\/div>\n                    <\/a>\n                <\/div>\n            <\/div>\n\n            <div class=\"right-side\">\n                <img decoding=\"async\"\n                    src=\"https:\/\/pabau.com\/wp-content\/uploads\/2026\/01\/Home-Page-Concept-4.webp\"\n                    alt=\"Pabau practice management platform\"\n                    loading=\"lazy\"\n                \/>\n            <\/div>\n        <\/div>\n        \n\n\n<h2 class=\"wp-block-heading\">Conclusion<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">CPT Code 00635 denials are preventable. The overwhelming majority trace back to missing modifiers, time unit errors, or incomplete documentation that could be caught before submission. The formula itself is fixed: 4 base units plus time units under Medicare, with physical status units added under ASA RVG and commercial-payer formulas. What varies is the accuracy of the inputs that feed into it.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Pabau keeps pre-anesthesia intake, clinical documentation, and treatment notes together in the patient record. This keeps the details a clean CPT Code 00635 claim depends on consistent across every case. <a href=\"https:\/\/pabau.com\/book-demo\/\">Book a demo<\/a> to see how Pabau supports anesthesia documentation and billing for your practice.<\/p>\n\n\n        <div id=\"expert_picks\">\n            <div class=\"header\">\n                                    <img decoding=\"async\" src=\"https:\/\/pabau.com\/wp-content\/uploads\/2025\/11\/Expert-Picks.svg\" alt=\"Continue your research\" height=\"42\" width=\"42\">\n                                <h3>Continue your research<\/h3>\n            <\/div>\n            <div class=\"content\">\n                                                            <div class=\"item\">\n                            <div>\n                                <svg width=\"20\" height=\"27\" viewBox=\"0 0 20 27\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">\n                                    <path\n                                        d=\"M18.6223 14.3857C19.1246 13.8975 19.1246 13.1045 18.6223 12.6162L12.1938 6.36621C11.6915 5.87793 10.8759 5.87793 10.3737 6.36621C9.87143 6.85449 9.87143 7.64746 10.3737 8.13574L14.6125 12.2529H2.28571C1.57455 12.2529 1 12.8115 1 13.5029C1 14.1943 1.57455 14.7529 2.28571 14.7529H14.6085L10.3777 18.8701C9.87545 19.3584 9.87545 20.1514 10.3777 20.6396C10.8799 21.1279 11.6955 21.1279 12.1978 20.6396L18.6263 14.3896L18.6223 14.3857Z\"\n                                        fill=\"#54B2D3\" \/>\n                                <\/svg>\n                            <\/div>\n                            <p><strong>Need to review related billing codes for spinal procedures?<\/strong> <a href=\"https:\/\/pabau.com\/procedure-codes\/coaching-cpt-codes\/\" rel=\"noopener\">Coaching CPT codes<\/a> provides a structured reference for adjacent procedure code families.<\/p>\n                        <\/div>\n                                                                                <div class=\"item\">\n                            <div>\n                                <svg width=\"20\" height=\"27\" viewBox=\"0 0 20 27\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">\n                                    <path\n                                        d=\"M18.6223 14.3857C19.1246 13.8975 19.1246 13.1045 18.6223 12.6162L12.1938 6.36621C11.6915 5.87793 10.8759 5.87793 10.3737 6.36621C9.87143 6.85449 9.87143 7.64746 10.3737 8.13574L14.6125 12.2529H2.28571C1.57455 12.2529 1 12.8115 1 13.5029C1 14.1943 1.57455 14.7529 2.28571 14.7529H14.6085L10.3777 18.8701C9.87545 19.3584 9.87545 20.1514 10.3777 20.6396C10.8799 21.1279 11.6955 21.1279 12.1978 20.6396L18.6263 14.3896L18.6223 14.3857Z\"\n                                        fill=\"#54B2D3\" \/>\n                                <\/svg>\n                            <\/div>\n                            <p><strong>Looking for documentation frameworks for clinical records?<\/strong> <a href=\"https:\/\/pabau.com\/guides\/psychiatric-evaluation-template\/\" rel=\"noopener\">Psychiatric evaluation template<\/a> demonstrates the structured documentation approach that supports clean claims across procedure types.<\/p>\n                        <\/div>\n                                                                                <div class=\"item\">\n                            <div>\n                                <svg width=\"20\" height=\"27\" viewBox=\"0 0 20 27\" fill=\"none\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\">\n                                    <path\n                                        d=\"M18.6223 14.3857C19.1246 13.8975 19.1246 13.1045 18.6223 12.6162L12.1938 6.36621C11.6915 5.87793 10.8759 5.87793 10.3737 6.36621C9.87143 6.85449 9.87143 7.64746 10.3737 8.13574L14.6125 12.2529H2.28571C1.57455 12.2529 1 12.8115 1 13.5029C1 14.1943 1.57455 14.7529 2.28571 14.7529H14.6085L10.3777 18.8701C9.87545 19.3584 9.87545 20.1514 10.3777 20.6396C10.8799 21.1279 11.6955 21.1279 12.1978 20.6396L18.6263 14.3896L18.6223 14.3857Z\"\n                                        fill=\"#54B2D3\" \/>\n                                <\/svg>\n                            <\/div>\n                            <p><strong>Want to improve compliance across your billing workflows?<\/strong> <a href=\"https:\/\/pabau.com\/blog\/hipaa-compliance-checklist-for-primary-care\/\" rel=\"noopener\">HIPAA compliance checklist<\/a> covers the documentation and recordkeeping standards that apply to anesthesia billing records.<\/p>\n                        <\/div>\n                                                <\/div>\n        <\/div>\n    \n\n\n<h2 class=\"wp-block-heading\">Frequently asked questions<\/h2>\n\n\n\n<div class=\"schema-faq wp-block-yoast-faq-block\"><div class=\"schema-faq-section\" id=\"faq-question-1785234769478\"><h3 class=\"schema-faq-question\">What is CPT Code 00635 used for?<\/h3> <p class=\"schema-faq-answer\">CPT Code 00635 is used to report anesthesia services provided during diagnostic or therapeutic lumbar puncture procedures. It falls under the anesthesia section for procedures in the lumbar region, and covers both spinal tap procedures performed for cerebrospinal fluid analysis and therapeutic procedures performed to relieve elevated intracranial pressure. Both physician anesthesiologists and CRNAs may bill this code with the appropriate provider-role modifier.<\/p> <\/div> <div class=\"schema-faq-section\" id=\"faq-question-1785234769479\"><h3 class=\"schema-faq-question\">How many base units does CPT Code 00635 have?<\/h3> <p class=\"schema-faq-answer\">CPT Code 00635 carries 4 ASA-assigned base units. These base units are fixed and do not change based on the duration or complexity of the individual case. Medicare adds the 4 base units to time units (1 unit per 15 minutes of anesthesia time) to calculate total units before multiplying by the conversion factor. ASA RVG and commercial-payer formulas may also add physical status modifier units (P3 adds 1 unit, P4 adds 2, P5 adds 3).<\/p> <\/div> <div class=\"schema-faq-section\" id=\"faq-question-1785234769480\"><h3 class=\"schema-faq-question\">What modifiers are used with CPT Code 00635?<\/h3> <p class=\"schema-faq-answer\">CPT Code 00635 requires two modifier types on every claim: a provider-role modifier (AA for personally performed by anesthesiologist, QK for medical direction of 2-4 concurrent cases, QX for CRNA under medical direction, or QZ for CRNA without medical direction) and a physical status modifier (P1 through P6). The QS modifier is also added when the procedure is performed under monitored anesthesia care. Both modifier types are required; a claim missing either will typically reject before reaching the payer.<\/p> <\/div> <div class=\"schema-faq-section\" id=\"faq-question-1785234769481\"><h3 class=\"schema-faq-question\">Can a CRNA bill CPT Code 00635?<\/h3> <p class=\"schema-faq-answer\">Yes, CRNAs can bill CPT Code 00635, but the correct modifier depends on the supervision arrangement. A CRNA billing under physician medical direction uses modifier QX; a CRNA billing independently in a state that has opted out of the Medicare physician supervision requirement uses modifier QZ. State supervision requirements and individual payer contracts vary, so billing teams should verify the applicable rules before submitting CRNA claims for this code.<\/p> <\/div> <div class=\"schema-faq-section\" id=\"faq-question-1785234769482\"><h3 class=\"schema-faq-question\">What is the difference between CPT 00635 and CPT 62270?<\/h3> <p class=\"schema-faq-answer\">CPT 62270 is the surgical\/procedural code for diagnostic spinal puncture (the lumbar puncture procedure itself), while CPT 00635 is the anesthesia companion code reported by the anesthesia provider for the same procedure. Both codes may appear on the same patient encounter billed by different providers: the proceduralist bills 62270 and the anesthesia provider bills 00635. They should never be billed by the same provider for the same service.<\/p> <\/div> <div class=\"schema-faq-section\" id=\"faq-question-1785234769483\"><h3 class=\"schema-faq-question\">What documentation is required to support CPT Code 00635?<\/h3> <p class=\"schema-faq-answer\">Required documentation includes a pre-anesthesia evaluation with ASA physical status classification, precise anesthesia start and stop times, the identity and role of the anesthesia provider, an intraoperative monitoring record, agents and doses administered, and a post-anesthesia note. For MAC cases, documentation must also justify why moderate sedation was clinically insufficient. All records should be retrievable for a minimum of 7 years under Medicare requirements.<\/p> <\/div> <\/div>\n","protected":false},"excerpt":{"rendered":"<p>CPT Code 00635 reports anesthesia for lumbar puncture. It carries 4 base units, plus the modifiers and ICD-10 pairing payers require.<\/p>\n","protected":false},"author":81,"featured_media":168456,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_yoast_wpseo_linkdex":"","_yoast_wpseo_content_score":"","_yoast_wpseo_is_cornerstone":"","_yoast_wpseo_keywordsynonyms":"","_yoast_wpseo_focuskw_text_input":"","_seo_original_html":"","footnotes":""},"categories":[1433,1546],"tags":[4162,1162,4164,1432],"class_list":["post-168460","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-billing-codes","category-cpt-codes","tag-anesthesia-billing","tag-cpt-codes","tag-crna","tag-procedure-codes"],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v28.3 (Yoast SEO v28.3) - https:\/\/yoast.com\/product\/yoast-seo-premium-wordpress\/ -->\n<title>CPT Code 00635: Anesthesia for lumbar puncture billing guide<\/title>\n<meta name=\"description\" content=\"CPT Code 00635 reports anesthesia for lumbar puncture. It carries 4 base units, plus the modifiers and ICD-10 pairing payers require.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/pabau.com\/fr\/procedure-codes\/cpt-code-00635\/\" \/>\n<meta property=\"og:locale\" content=\"fr_FR\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"CPT Code 00635: Anesthesia for lumbar puncture billing guide\" \/>\n<meta property=\"og:description\" content=\"CPT Code 00635 reports anesthesia for lumbar puncture. It carries 4 base units, plus the modifiers and ICD-10 pairing payers require.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/pabau.com\/fr\/procedure-codes\/cpt-code-00635\/\" \/>\n<meta property=\"og:site_name\" content=\"Pabau\" \/>\n<meta property=\"article:publisher\" content=\"https:\/\/www.facebook.com\/Pabau\/\" \/>\n<meta property=\"article:published_time\" content=\"2026-07-28T14:16:59+00:00\" \/>\n<meta property=\"article:modified_time\" content=\"2026-08-17T11:38:13+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/pabau.com\/wp-content\/uploads\/2026\/07\/cpt-code-00635.webp\" \/>\n\t<meta property=\"og:image:width\" content=\"1200\" \/>\n\t<meta property=\"og:image:height\" content=\"630\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/webp\" \/>\n<meta name=\"author\" content=\"Aleksandar Kochovski\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:creator\" content=\"@pabaucrm\" \/>\n<meta name=\"twitter:site\" content=\"@pabaucrm\" \/>\n<meta name=\"twitter:label1\" content=\"\u00c9crit par\" \/>\n\t<meta name=\"twitter:data1\" content=\"Aleksandar Kochovski\" \/>\n\t<meta name=\"twitter:label2\" content=\"Dur\u00e9e de lecture estim\u00e9e\" \/>\n\t<meta name=\"twitter:data2\" content=\"14 minutes\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":\"Article\",\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/procedure-codes\\\/cpt-code-00635\\\/#article\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/procedure-codes\\\/cpt-code-00635\\\/\"},\"author\":{\"name\":\"Aleksandar Kochovski\",\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/#\\\/schema\\\/person\\\/73b672a49e20bfba8161e3c17ee3dda2\"},\"headline\":\"CPT Code 00635: Anesthesia for lumbar puncture billing guide\",\"datePublished\":\"2026-07-28T14:16:59+00:00\",\"dateModified\":\"2026-08-17T11:38:13+00:00\",\"mainEntityOfPage\":{\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/procedure-codes\\\/cpt-code-00635\\\/\"},\"wordCount\":2872,\"publisher\":{\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/#organization\"},\"image\":{\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/procedure-codes\\\/cpt-code-00635\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/pabau.com\\\/wp-content\\\/uploads\\\/2026\\\/07\\\/cpt-code-00635.webp\",\"keywords\":[\"Anesthesia Billing\",\"CPT Codes\",\"CRNA\",\"procedure codes\"],\"articleSection\":[\"Billing Codes\",\"CPT Codes\"],\"inLanguage\":\"fr-FR\"},{\"@type\":[\"WebPage\",\"FAQPage\"],\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/procedure-codes\\\/cpt-code-00635\\\/\",\"url\":\"https:\\\/\\\/pabau.com\\\/fr\\\/procedure-codes\\\/cpt-code-00635\\\/\",\"name\":\"CPT Code 00635: Anesthesia for lumbar puncture billing guide\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/#website\"},\"primaryImageOfPage\":{\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/procedure-codes\\\/cpt-code-00635\\\/#primaryimage\"},\"image\":{\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/procedure-codes\\\/cpt-code-00635\\\/#primaryimage\"},\"thumbnailUrl\":\"https:\\\/\\\/pabau.com\\\/wp-content\\\/uploads\\\/2026\\\/07\\\/cpt-code-00635.webp\",\"datePublished\":\"2026-07-28T14:16:59+00:00\",\"dateModified\":\"2026-08-17T11:38:13+00:00\",\"description\":\"CPT Code 00635 reports anesthesia for lumbar puncture. 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It combines scheduling, electronic health records, clinical forms, payments, marketing automation, reporting, and patient engagement tools into one secure cloud system to help practices streamline operations and grow their business.\",\"foundingDate\":\"2011-10-20\",\"numberOfEmployees\":{\"@type\":\"QuantitativeValue\",\"minValue\":\"201\",\"maxValue\":\"500\"}},{\"@type\":\"Person\",\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/#\\\/schema\\\/person\\\/73b672a49e20bfba8161e3c17ee3dda2\",\"name\":\"Aleksandar Kochovski\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"fr-FR\",\"@id\":\"https:\\\/\\\/pabau.com\\\/wp-content\\\/uploads\\\/2026\\\/06\\\/cropped-aleksandar-kochovski-profile-picture-96x96.jpeg\",\"url\":\"https:\\\/\\\/pabau.com\\\/wp-content\\\/uploads\\\/2026\\\/06\\\/cropped-aleksandar-kochovski-profile-picture-96x96.jpeg\",\"contentUrl\":\"https:\\\/\\\/pabau.com\\\/wp-content\\\/uploads\\\/2026\\\/06\\\/cropped-aleksandar-kochovski-profile-picture-96x96.jpeg\",\"caption\":\"Aleksandar Kochovski\"},\"description\":\"Aleksandar is a content strategist and editor working in tech publishing, with a background in higher education. He specializes in topics around compliance in software solutions. When he's not writing at Pabau, you can find him tending to his bonsai collection or hitting the gym.\",\"url\":\"https:\\\/\\\/pabau.com\\\/fr\\\/blog\\\/author\\\/aleksandar-kochovski\\\/\"},{\"@type\":\"Question\",\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/procedure-codes\\\/cpt-code-00635\\\/#faq-question-1785234769478\",\"position\":1,\"url\":\"https:\\\/\\\/pabau.com\\\/fr\\\/procedure-codes\\\/cpt-code-00635\\\/#faq-question-1785234769478\",\"name\":\"What is CPT Code 00635 used for?\",\"answerCount\":1,\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"CPT Code 00635 is used to report anesthesia services provided during diagnostic or therapeutic lumbar puncture procedures. It falls under the anesthesia section for procedures in the lumbar region, and covers both spinal tap procedures performed for cerebrospinal fluid analysis and therapeutic procedures performed to relieve elevated intracranial pressure. Both physician anesthesiologists and CRNAs may bill this code with the appropriate provider-role modifier.\",\"inLanguage\":\"fr-FR\"},\"inLanguage\":\"fr-FR\"},{\"@type\":\"Question\",\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/procedure-codes\\\/cpt-code-00635\\\/#faq-question-1785234769479\",\"position\":2,\"url\":\"https:\\\/\\\/pabau.com\\\/fr\\\/procedure-codes\\\/cpt-code-00635\\\/#faq-question-1785234769479\",\"name\":\"How many base units does CPT Code 00635 have?\",\"answerCount\":1,\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"CPT Code 00635 carries 4 ASA-assigned base units. These base units are fixed and do not change based on the duration or complexity of the individual case. Medicare adds the 4 base units to time units (1 unit per 15 minutes of anesthesia time) to calculate total units before multiplying by the conversion factor. ASA RVG and commercial-payer formulas may also add physical status modifier units (P3 adds 1 unit, P4 adds 2, P5 adds 3).\",\"inLanguage\":\"fr-FR\"},\"inLanguage\":\"fr-FR\"},{\"@type\":\"Question\",\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/procedure-codes\\\/cpt-code-00635\\\/#faq-question-1785234769480\",\"position\":3,\"url\":\"https:\\\/\\\/pabau.com\\\/fr\\\/procedure-codes\\\/cpt-code-00635\\\/#faq-question-1785234769480\",\"name\":\"What modifiers are used with CPT Code 00635?\",\"answerCount\":1,\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"CPT Code 00635 requires two modifier types on every claim: a provider-role modifier (AA for personally performed by anesthesiologist, QK for medical direction of 2-4 concurrent cases, QX for CRNA under medical direction, or QZ for CRNA without medical direction) and a physical status modifier (P1 through P6). The QS modifier is also added when the procedure is performed under monitored anesthesia care. Both modifier types are required; a claim missing either will typically reject before reaching the payer.\",\"inLanguage\":\"fr-FR\"},\"inLanguage\":\"fr-FR\"},{\"@type\":\"Question\",\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/procedure-codes\\\/cpt-code-00635\\\/#faq-question-1785234769481\",\"position\":4,\"url\":\"https:\\\/\\\/pabau.com\\\/fr\\\/procedure-codes\\\/cpt-code-00635\\\/#faq-question-1785234769481\",\"name\":\"Can a CRNA bill CPT Code 00635?\",\"answerCount\":1,\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"Yes, CRNAs can bill CPT Code 00635, but the correct modifier depends on the supervision arrangement. A CRNA billing under physician medical direction uses modifier QX; a CRNA billing independently in a state that has opted out of the Medicare physician supervision requirement uses modifier QZ. State supervision requirements and individual payer contracts vary, so billing teams should verify the applicable rules before submitting CRNA claims for this code.\",\"inLanguage\":\"fr-FR\"},\"inLanguage\":\"fr-FR\"},{\"@type\":\"Question\",\"@id\":\"https:\\\/\\\/pabau.com\\\/fr\\\/procedure-codes\\\/cpt-code-00635\\\/#faq-question-1785234769482\",\"position\":5,\"url\":\"https:\\\/\\\/pabau.com\\\/fr\\\/procedure-codes\\\/cpt-code-00635\\\/#faq-question-1785234769482\",\"name\":\"What is the difference between CPT 00635 and CPT 62270?\",\"answerCount\":1,\"acceptedAnswer\":{\"@type\":\"Answer\",\"text\":\"CPT 62270 is the surgical\\\/procedural code for diagnostic spinal puncture (the lumbar puncture procedure itself), while CPT 00635 is the anesthesia companion code reported by the anesthesia provider for the same procedure. Both codes may appear on the same patient encounter billed by different providers: the proceduralist bills 62270 and the anesthesia provider bills 00635. 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He specializes in topics around compliance in software solutions. When he's not writing at Pabau, you can find him tending to his bonsai collection or hitting the gym.","url":"https:\/\/pabau.com\/fr\/blog\/author\/aleksandar-kochovski\/"},{"@type":"Question","@id":"https:\/\/pabau.com\/fr\/procedure-codes\/cpt-code-00635\/#faq-question-1785234769478","position":1,"url":"https:\/\/pabau.com\/fr\/procedure-codes\/cpt-code-00635\/#faq-question-1785234769478","name":"What is CPT Code 00635 used for?","answerCount":1,"acceptedAnswer":{"@type":"Answer","text":"CPT Code 00635 is used to report anesthesia services provided during diagnostic or therapeutic lumbar puncture procedures. It falls under the anesthesia section for procedures in the lumbar region, and covers both spinal tap procedures performed for cerebrospinal fluid analysis and therapeutic procedures performed to relieve elevated intracranial pressure. Both physician anesthesiologists and CRNAs may bill this code with the appropriate provider-role modifier.","inLanguage":"fr-FR"},"inLanguage":"fr-FR"},{"@type":"Question","@id":"https:\/\/pabau.com\/fr\/procedure-codes\/cpt-code-00635\/#faq-question-1785234769479","position":2,"url":"https:\/\/pabau.com\/fr\/procedure-codes\/cpt-code-00635\/#faq-question-1785234769479","name":"How many base units does CPT Code 00635 have?","answerCount":1,"acceptedAnswer":{"@type":"Answer","text":"CPT Code 00635 carries 4 ASA-assigned base units. These base units are fixed and do not change based on the duration or complexity of the individual case. Medicare adds the 4 base units to time units (1 unit per 15 minutes of anesthesia time) to calculate total units before multiplying by the conversion factor. ASA RVG and commercial-payer formulas may also add physical status modifier units (P3 adds 1 unit, P4 adds 2, P5 adds 3).","inLanguage":"fr-FR"},"inLanguage":"fr-FR"},{"@type":"Question","@id":"https:\/\/pabau.com\/fr\/procedure-codes\/cpt-code-00635\/#faq-question-1785234769480","position":3,"url":"https:\/\/pabau.com\/fr\/procedure-codes\/cpt-code-00635\/#faq-question-1785234769480","name":"What modifiers are used with CPT Code 00635?","answerCount":1,"acceptedAnswer":{"@type":"Answer","text":"CPT Code 00635 requires two modifier types on every claim: a provider-role modifier (AA for personally performed by anesthesiologist, QK for medical direction of 2-4 concurrent cases, QX for CRNA under medical direction, or QZ for CRNA without medical direction) and a physical status modifier (P1 through P6). The QS modifier is also added when the procedure is performed under monitored anesthesia care. Both modifier types are required; a claim missing either will typically reject before reaching the payer.","inLanguage":"fr-FR"},"inLanguage":"fr-FR"},{"@type":"Question","@id":"https:\/\/pabau.com\/fr\/procedure-codes\/cpt-code-00635\/#faq-question-1785234769481","position":4,"url":"https:\/\/pabau.com\/fr\/procedure-codes\/cpt-code-00635\/#faq-question-1785234769481","name":"Can a CRNA bill CPT Code 00635?","answerCount":1,"acceptedAnswer":{"@type":"Answer","text":"Yes, CRNAs can bill CPT Code 00635, but the correct modifier depends on the supervision arrangement. A CRNA billing under physician medical direction uses modifier QX; a CRNA billing independently in a state that has opted out of the Medicare physician supervision requirement uses modifier QZ. State supervision requirements and individual payer contracts vary, so billing teams should verify the applicable rules before submitting CRNA claims for this code.","inLanguage":"fr-FR"},"inLanguage":"fr-FR"},{"@type":"Question","@id":"https:\/\/pabau.com\/fr\/procedure-codes\/cpt-code-00635\/#faq-question-1785234769482","position":5,"url":"https:\/\/pabau.com\/fr\/procedure-codes\/cpt-code-00635\/#faq-question-1785234769482","name":"What is the difference between CPT 00635 and CPT 62270?","answerCount":1,"acceptedAnswer":{"@type":"Answer","text":"CPT 62270 is the surgical\/procedural code for diagnostic spinal puncture (the lumbar puncture procedure itself), while CPT 00635 is the anesthesia companion code reported by the anesthesia provider for the same procedure. Both codes may appear on the same patient encounter billed by different providers: the proceduralist bills 62270 and the anesthesia provider bills 00635. They should never be billed by the same provider for the same service.","inLanguage":"fr-FR"},"inLanguage":"fr-FR"},{"@type":"Question","@id":"https:\/\/pabau.com\/fr\/procedure-codes\/cpt-code-00635\/#faq-question-1785234769483","position":6,"url":"https:\/\/pabau.com\/fr\/procedure-codes\/cpt-code-00635\/#faq-question-1785234769483","name":"What documentation is required to support CPT Code 00635?","answerCount":1,"acceptedAnswer":{"@type":"Answer","text":"Required documentation includes a pre-anesthesia evaluation with ASA physical status classification, precise anesthesia start and stop times, the identity and role of the anesthesia provider, an intraoperative monitoring record, agents and doses administered, and a post-anesthesia note. For MAC cases, documentation must also justify why moderate sedation was clinically insufficient. 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