Outpatient Surgery (Anesthesia Text)

If a patient can safely undergo an operation, recover, and go home on the same day, several potential advantages arise – decreased costs through more efficient resource utilization, increased hospital bed availability, lower risk of resistant bacterial strain transmission, and quicker return to family, social, and working life. Paul White claims that “More aggressive rehabilitation leads to faster recovery of organ function, fewer surgical and anesthetic complications, reduced mental and physical disability, and, most importantly, earlier resumption of normal activities,” although he provides no citation. [White PF. Anesth Analg 90: 1234, 2000]

Administrative Considerations

The ASA guidelines (Committee on Ambulatory Surgical Care and the ASA Task Force on Office-Based Anesthesia, see www.asahq.org) state that outpatient surgery centers must have an established agreement with a nearby hospital (for unexpected transfers, admits) in order to safely practice office-based anesthesia. Office-based anesthetics should revolve around SAFE (short-acting fast emergence) drugs such as propofol and remifentanil.


Some data that suggest both morbid obesity [Davies et. al. Anaesthesia 56: 1112, 2001] and obstructive sleep apnea [Sabers C et al. Anesth Analg 96: 1328, 2003] are not predictors of re-admission or delayed discharge from ambulatory anesthesia. ASA III (and possibly IV [Dunn PF. Clinical Anesthesia Procedures of the Massachusetts General Hospital, 7th ed. LWW (Philadelphia) p. 563, 2007]) should not be excluded if their diseases are under control [Ansell et. al. Br J Anaesth 92: 71, 2004]. Length of surgery is not a criteria as there is little if any relationship between duration of surgery and recovery. Note that any preterm infant with post-gestational age < 50 weeks should not be discharged for at least 23 hours because of the risk of apnea.

Procedures That May Be Safely Performed in Outpatients with OSA

Procedures That May Be Safely Performed on an Outpatient Basis for Patients with OSA [Anesthesiology 104: 1081, 2006]

Type of Surgery/Anesthesia Opinion
Superficial surgery/local or regional anesthesia Agree
Superficial surgery/general anesthesia Equivocal
Airway surgery (adult, e.g., uvulopalatopharyngoplasty) Disagree
Tonsillectomy in children less than 3 years old Disagree
Tonsillectomy in children greater than 3 years old Equivocal
Minor orthopedic surgery/local or regional anesthesia Agree
Minor orthopedic surgery/general anesthesia Equivocal
Gynecologic laparoscopy Equivocal
Laparoscopic surgery, upper abdomen Disagree
Lithotripsy Agree

Exclusion Criteria for Outpatient Surgery

All Patients

  • Major blood loss
  • Major surgery
  • ASA III or IV and requiring complex or long-duration monitoring postoperatively
  • Morbidly obese patients who have OSA (OSA alone not a contraindication, see above)
  • Any patient with recent URI


  • < 56 weeks postconceptual age and < 32 weeks postgestation when born (56:32)
  • < 54 weeks postconceptual age and < 35 weeks postgestation when born (54:35)
  • History of apnea
  • Cardiovascular disease
  • Anemia

Preoperative Considerations

Psychosocial issues may dominate medical issues in this patient population (insurance concerns, transportation, lodging, etc.). Most of the time outpatient surgery patients continue to take their PO meds through surgery. Routine labs are not indicated – labs should be ordered on an as-needed basis.

Note that both children and patients with cognitive deficits have higher cancellation rates, thus should likely be asked to arrive earlier (so that an attempt can be made to reach them, or there is adequate room to manipulate the schedule).

NPO after midnight is archaic, and leads to potentially unnecessary hypovolemia. Clear fluids can be consumed up to two hours before surgery (breast milk up to 4 hours, formula up to 6 hours, and light meals up to 6 hours).

ASA Guidelines: Fasting Recommendations to Reduce the Risk of Pulmonary Aspiration

ASA Guidelines: Fasting Recommendations to Reduce the Risk of Pulmonary Aspiration

  • Clear liquids: 2 hrs
  • Breast milk: 4 hrs
  • Infant formula, non-human milk, or light meal: 6 hrs

Long-acting insulin (ex. Lantus) should be taken at 1/2 dose on the morning of surgery, with medium and short-acting insulins held.

Consider placing an antecubital IV as it diminishes the pain associated with propofol.

Day of Surgery

Many pediatric patients will have rhinorrhea – this is common, and usually allergic. An upper respiratory infection should, however be sought, and consider postponing surgery if found.

Premedicating drugs can be administered safely if dosage is taken into consideration – there is less room to maneuver, however, as these patients intend to go home. Consider fentanyl 1 ucg/kg and midazolam 0.04 mg/kg.

PONV prophylaxis should be considered in any patient at risk for this potentially disposition-changing complication. Consider minimizing opiate use in patients at high risk.

Anesthesia Techniques

General Anesthesia

Propofol is the IV induction agent of choice, as patients in the outpatient setting are generally able to respond to command, sit, and stand 29 minutes earlier as compared to a thiopental induction [Korttila K et. al. Anesthesiology 76: 676, 1992]. Furthermore, data from 24,157 PACU admissions found that critical respiratory events were 2.5 times as likely following thiopental induction as compared to propofol [Rose DK et al. Anesthesiology 81: 410, 1994].

Avoid etomidate as an IV induction agent because it increases the incidence of PONV and myoclonus is potentially painful. Consider using propofol as part of the general anesthetic as well, as it reduces the incidence of PONV by 19% compared to volatile anesthetics [Apfel CC et. al. NEJM 350: 2441, 2004].

According to Stoelting, LMA causes less postoperative discomfort than endotracheal intubation [Stoelting RK. Basics of Anesthesia, 5th ed. Elsevier (China) p. 544, 2007], but this is not born out in either the pediatric [Splinter WM et. al. Can J Anaesth 41: 1081, 1994] or adult [Zimmert M et. al. Eur J Anaesthesiol 16: 511, 1999; Hamdan AL et. al. J Laryngol Otol 1222: 829, 2008] literature. The LMA ProSeal attempts to address the shortcomings of the LMA (inability to protect the airway and questionable use in positive pressure ventilation). Avoidance of succinylcholine should be considered due to the potential for myalgias, although mivacurium is a reasonable alternative. If SCh is given, always give a defasciculating dose of a non-depolarizing NMBD first.

Maintenance is often achieved with nitrous oxide plus a volatile anesthetic, although PONV is a concern with nitrous. Consider TIVA as an alternative to volatile agents, and encourage liberal use of local anesthesia for pain control.

Central Blocks

Use of thin (25 gauge or higher) needles plus a rounded of pencil-point needle (Sprotte, Whitacre, Pencan) reduces the incidence of post-dural puncture headache. There is significant debate about whether or not early ambulation prevents headaches. TENS has dampened the enthusiasm for spinal anesthesia. All of these patients should receive a follow up telephone call. Remember that 5-10% of outpatients who undergo a spinal will develop a post-dural puncture headache [Dunn PF. Clinical Anesthesia Procedures of the Massachusetts General Hospital, 7th ed. LWW (Philadelphia) p. 566, 2007], and that men may develop urinary retention.

Epidural analgesia is a reasonable alternative to spinal in some procedures, and markedly reduces the risk of PDPH.


Regional block plus sedation and availability of rescue GA is the ideal option for many cases performed on the extremities.


Midazolam and propofol are the first-line medications, although for more painful procedures consider fentanyl (25-50 ucg IV), or infusions of remifentanil (0.075-0.15 ucg/kg/min) or ketamine (5-20 ucg/kg/min).

Postoperative Considerations

The age at which full-term infants or ex-premature infants can safely undergo outpatient surgery is controversial [Fisher DM. Anesthesiology 82: 807, 1995]. Cote combined data from eight prospective studies (255 patients) to develop an algorithm based on gestational age, post-conceptual age, apnea at home, size at gestational age, and anemia [Cote CJ et. al. Anesthesiology 82: 809, 1995]. Cotes data showed that the incidence of apnea following inguinal hernia repair did not fall below 5% until gestational age reached 35 weeks and post-conceptual age reached 48 weeks, and that the incidence of apnea following inguinal hernia repair did not fall below 1% until gestational age reached 32 weeks and post-conceptual age reached 56 weeks (or post-gestational 35 weeks with post-conceptual 54 weeks). Any infant that exhibits apnea, has a history of apnea, or is anemic, should not undergo outpatient surgery.


Nursing variability is the single most important factor in discharge from an outpatient facility [Pavlin DJ et al. Anesth Analg 87: 816, 1998]. PONV, pain, and drowsiness are the most common reasons for prolonged stay in the PACU. Urinary retention is also a concern. In general, the rate of unplanned admission is < 1%. Always explain to patients that manual dexterity may be impaired for as long as 48 hours after surgery. In order to bypass the PACU, a Fast-Track Criteria system has been developed, and which mandates a score of 12 or higher prior to skipping the PACU [White PF et. al. Anesth Analg 88: 1069, 1999].