RISKS RELATED TO LOCATION OF SURGERY AND POSTOPERATIVE MONITORING

Perioperative risk varies among hospitals for major procedures such as coronary artery bypass grafting and

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Although the value of postoperative monitoring and care in an ICU has never been documented in a randomized clinical trial, many investigators have suggested that such care is one of the primary reasons for improved morbidity and mortality in recent years. For patients undergoing major vascular surgery, several investigators have suggested that more intense postoperative monitoring could obviate the need for preoperative cardiac testing and revascularization.^{[185] [186]} One potential value of risk assessment is the identification of patients who could benefit from referral to centers with more extensive perioperative resources. Patients with a low probability of perioperative morbidity and mortality could have surgery performed locally, and individuals at higher risk could receive benefit from transfer to a larger center.

It is estimated that 60% of all surgical procedures are performed on an outpatient basis, and this percentage is increasing annually. Review of the literature to determine the safety of this shift from the inpatient to the outpatient arena reveals a striking lack of good evidence to document such safety. Warner and coworkers^[181] studied the safety of surgery on an ambulatory basis in 38,598 patients. They documented only 33 episodes of major morbidity or mortality within 1 month after surgery. Major morbidity included 14 myocardial infarctions, 7 central nervous system deficits, 5 pulmonary embolisms, and 5 cases of respiratory failure (see Fig. 24-3 ). When adjusted for age and gender, these rates of major morbidity and mortality were lower than those expected in the nonsurgical population. However, Olmstead County, Minnesota, the site of Warner's study, represented a unique population with high standards for health care. Facilities were immediately available to care for any unexpected emergency or admission. The study was performed during an era in which the patients were primarily healthy individuals undergoing peripheral or superficial procedures.

The type and extent of surgical procedures performed in an outpatient setting is constantly changing, and procedures associated with greater perioperative risk are increasingly performed on an outpatient basis. The value of overnight observation in a hospital setting as opposed to immediate discharge home has been studied for a number of surgical procedures. One of the first procedures advocated to be performed on an ambulatory basis was tonsillectomy. In 1968, a case series of 40,000 outpatient tonsillectomies was reported with no deaths.^[187A] Details on patient selection and length of postoperative monitoring were vague. Based on insurance company and state mandates, performance of tonsillectomy on an outpatient basis became routine.^[187] Beginning in the mid-1980s and continuing in the 1990s, a number of articles evaluated the risk of early discharge. For example, Carithers and colleagues^[188] at Ohio State University analyzed 3000 tonsillectomies and argued that early discharge might be hazardous and economically unwarranted. The rate of readmission for active bleeding between 5 and 24 hours after surgery was reported to be between 0.2% and 0.5%.^{[189] [190] [191] [192] [193]} Although the absolute rate of readmission is low, it represents a substantial risk for children. Whether the benefits of early discharge outweigh the risks is a decision society will have to make.

Another procedure being performed on an outpatient basis is mastectomy. An analysis of Medicare claims demonstrated that the rate of outpatient mastectomy

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There is increasing interest in performing surgery and providing anesthesia in office-based settings. There are no good data to determine the safety of such practices, although there have been a flurry of high-profile cases in which patients have died in plastic surgery and dental offices. Anesthesia and sedation are frequently provided by individuals other than anesthesiologists or nurse anesthetists in these settings, and there are reports of office nurses or even clerical help administering anesthetic agents.

There has been an attempt to quantify the incidence of complications in an office-based setting. The American Association for Ambulatory Plastic Surgery Facilities (AAAPSF) mailed a survey to their members to determine the incidence of complications occurring in office facilities.^[195] The overall response rate was 57%. The findings showed that 0.47% of patients had at least one complication, including bleeding, hypertension, infection, and hypotension, and 1 of 57,000 patients died. Assuming that these are very minor procedures performed only on healthy individuals, a rate of mortality that is three times the current estimate for anesthesia-related complications is a concern. Further research and quality-assurance mechanisms need to be in place before this practice is generalized. One of the problems inherent in an office-based setting is the inability to perform quality-assurance reviews. For example, few surgeons or anesthesiologists would be willing to allow their "competitors" to review their complication rate unless mandated to perform such a review.

The problems in evaluating the risk of outpatient surgery include the lack of any large database compiled from a diverse group of settings and the lack of uniform standards for quality assurance. Although the Joint Committee for the Accreditation of Hospitals accredits ASCs, as do two other organizations, accreditation is still not wide-spread and remains optional. Although ambulatory care centers have led the way in performing appropriate follow-up of their patients at home, such follow-up is not uniformly complete. As of 1998, only three states had established regulations for office-based settings, and these regulations vary greatly. The implications of the lack of regulation are unclear, but issues related to emergency plans and resuscitation equipment may be left to the discretion of the local personnel, potentially placing patients at risk.

The decision to perform a procedure in an ambulatory setting is based on the surgeon's preference and the insurance company's mandates. Frequently, a case series by a surgeon or review by an insurance company demonstrates that otherwise healthy individuals can undergo a given procedure safely in an outpatient setting. The need for subsequent medical attention or use of resources at home is not necessarily taken into account. This may lead to insurance company mandates that the procedure be performed in all patients in an ambulatory setting. The generalization from healthy individuals to patients with comorbid disease may not be justified in the absence of data to demonstrate its safety. As an advocate for the patient, the anesthesiologist should continue to evaluate the safety of such practices and determine when the risks of ambulatory surgery outweigh any potential benefits. It is also important to determine whether the insurance companies are in essence transferring the risk of undergoing surgery from the medical system to the patient.