RATIONALE FOR AMBULATORY SURGERY

Ambulatory surgery can offer a number of advantages for patients, health care providers, third-party payers, and even hospitals ( Table 68-1 ). Many patients, especially those at the extremes of age, prefer to have their surgical procedures performed as outpatients because it decreases separation from their familiar home environment. Postoperative cognitive dysfunction was less frequent in elderly patients undergoing minor surgery on an ambulatory basis, thus suggesting that hospitalization should be avoided whenever possible.^[8] A survey of patient satisfaction reported that 97% of the respondents would choose day surgery for a future surgical procedure.^[9] Unlike inpatient surgery, ambulatory surgery does not depend on the availability of a hospital bed, and patients thus have a greater degree of flexibility in scheduling the timing of their operation. Outpatient surgery has been performed safely with a remarkably low incidence of both minor and major morbidity.^[10]

Studies have shown that unanticipated admission to the hospital occurs in less than 1% of patients and that return visits to the hospital occur in less than 3% of patients after ambulatory surgical procedures.^{[11] [12] [13]} The vast majority of readmissions (and emergency room visits) were related to surgical complications. ^[14] Of the surgical subspecialties, otolaryngology had the highest and gynecology the lowest incidence of unanticipated admissions. The lower infection rate associated with outpatient surgery is particularly beneficial to pediatric, geriatric, and immunocompromised patients.^[15] Risk factors associated with an increase in surgical site infections were the use of postoperative antibiotics and prolonged surgical times.^[16] Finally, there is evidence that the incidence of respiratory complications (i.e., pulmonary embolus and pneumonia)

TABLE 68-1 -- Benefits of ambulatory surgery

Patient preference, especially children and the elderly

Lack of dependence on the availability of hospital beds

Greater flexibility in scheduling operations

Low morbidity and mortality

Lower incidence of infection

Lower incidence of respiratory complications

Higher volume of patients (greater efficiency)

Shorter surgical waiting lists

Lower overall procedural costs

Less preoperative testing and postoperative medication

Modified from Snyder DS, Pasternak LR: Facility design and procedural safety. In White PF (ed): Ambulatory Anesthesia and Surgery. London, WB Saunders, 1997, p 61.

may also be decreased.^[17] Even outpatients with obstructive sleep apnea syndrome were not found to have an increased incidence of complications or unanticipated admissions.^[18]

Minimally invasive ambulatory surgery has clear economic benefits. For example, when compared with conventional "open" procedures, the use of minimally invasive surgical techniques can reduce overall hospital costs by almost 50%.^[19] Another cost-saving benefit relates to the greater efficiency of ambulatory centers, which results in higher operating room utilization and faster turnover times.^[7] The ability to care for larger volumes of patients can lead to reduced surgical waiting lists. When compared with similar procedures performed in hospitalized patients, less preoperative laboratory testing is needed for ambulatory surgery, and patients have a reduced demand for postoperative medications. These factors all contribute to the 25% to 75% reduction in overall cost for most operations performed in the outpatient setting.^[20] However, procedures requiring specialized postoperative care (e.g., extensive physical therapy or pain management) may be more costly when performed on an outpatient basis.^[21] Patients who need blood transfusions or intravenous antibiotics and parenteral opioid analgesics are best handled as same-day (23-hour) admissions. Improvements in home nursing and outpatient physical therapy may enable these services to be performed in the patient's home. Assuming that the number of available hospital beds continues to decline in the future, the growth of ambulatory surgery will lead to an increased return on investment of the health care dollar.