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Outpatient + Ambulatory Anesthesia
TEXTGeneral Principles · 7 min read
ASC + office-based + same-day-surgery selection, fast-track criteria, PADSS discharge, prevention of unanticipated admission.
After this lesson you can
2 min read7 sections- Select ambulatory candidates.
- Plan anesthetic for fast-track discharge.
- Manage common ambulatory complications.
- Apply PADSS discharge scoring.
Patient selection
- severe OSA without home CPAP
- recent MI <30-60 days
- decompensated HF
- severe valve disease
- end-stage renal/hepatic
- malignant hyperthermia susceptibility (need extended monitoring)
- recent stroke <3 months
- escort + caregiver requirement post-op
Age: extremes of age (<3 mo, >85) need case-by-case judgment.
BMI >50 + OSA consider inpatient.
Procedure suitability
4-6 hr ideal.Minimal blood loss, minimal fluid shifts, controllable postop pain, low PONV risk, no need for prolonged observation.
- most outpatient gen surg
- urology
- ortho (knee/shoulder scope, hand)
- ENT
- ophtho
- dental
- GI endo
- pain procedures
- total joint (T-1 protocols emerging)
- laparoscopic chole
- hernia in obese
Anesthetic technique selection
Propofol > etomidate for induction (PONV + emergence).
Desflurane + sevoflurane > isoflurane (faster wake-up).
Remifentanil > fentanyl > morphine (no late respiratory depression).
Multimodal opioid-sparing: APAP + NSAID + dex + regional.
Avoid full-dose long-acting opioids day of surgery.
LMA preferred over ETT when appropriate.
Regional + GA combo accelerates discharge.
PONV — outpatient deal-breaker
Apfel score 4 factors.
Multi-class prophylaxis for Apfel ≥3: 5HT3 (ondansetron), steroid (dex 4-8 mg), neurokinin (aprepitant in high-risk), antihistamine (promethazine), butyrophenone (haloperidol low-dose), antimuscarinic (scopolamine patch).
TIVA propofol-based for very high-risk.
Acupressure P6 bands as adjunct.
Adequate hydration.
Fast-tracking + PADSS discharge
- alert + oriented
- stable vital signs
- no pain
- no nausea
- no airway concern
White Fast-Track score ≥12/14 or modified Aldrete ≥9.
PADSS (Post-Anesthetic Discharge Scoring System) — 5 categories scored 0-2: vital signs, ambulation, N/V, pain, bleeding.
Score ≥9 for discharge.
Voiding not required for most ambulatory; required for spinal/epidural + GU procedures.
Office-based anesthesia (OBA)
- no built-in code team
- longer EMS response
- fewer rescue resources
Patient selection MORE conservative than ASC.
- AED/defibrillator
- suction
- oxygen + reserve
- code drugs (dantrolene if MH-trigger used)
- capnography (mandatory per ASA standards even for moderate sedation)
- AAAHC
- AAAASF
- JCAHO
State regulations vary by procedure level (Level I-IV).
Unanticipated admission — what drives it
- PONV refractory to treatment
- uncontrolled pain
- urinary retention (spinal/epidural)
- bleeding
- surgical complication
- oversedation
- prolonged block
- aggressive PONV prophylaxis
- multimodal analgesia
- post-spinal voiding plan
- careful regional with shorter-acting LA for ambulatory blocks
Admission rate benchmark <1-3% depending on case mix.
⚠ Common pitfalls
- Long-acting opioids in ambulatory — delayed discharge from sedation/PONV.
- Spinal anesthesia with long-acting LA in outpatient — prolonged recovery.
- Skipping pre-op counseling on responsible-adult escort — discharge blocked at PACU.
- OSA patient ambulatory without risk stratification — STOP-BANG screening mandatory.
💎 Clinical pearls
- TIVA with propofol + remi + short-acting opioid — fastest emergence + lowest PONV.
- Short-acting LA for ambulatory spinal: chloroprocaine, lidocaine; avoid bupivacaine.
- Multimodal analgesia + dexamethasone + ondansetron at induction — standard PONV bundle.
- PADSS ≥9 for ambulatory discharge: stable vitals, controlled pain, ambulation, no PONV.
Recap
- TIVA with propofol + remi + short-acting opioid — fastest emergence + lowest PONV.
- Short-acting LA for ambulatory spinal: chloroprocaine, lidocaine; avoid bupivacaine.
- Multimodal analgesia + dexamethasone + ondansetron at induction — standard PONV bundle.
- PADSS ≥9 for ambulatory discharge: stable vitals, controlled pain, ambulation, no PONV.
Mark each section done to complete the module.