Background

Ambulatory surgeries have increased in recent decades to help improve efficiency and cost; however, there is a potential need for unplanned post-operative admission, clinic visits, or evaluation in the emergency department (ED).

Hypothesis/Purpose: The purpose of this study was to determine the frequency, reasons, and factors influencing unplanned 24 hour post-operative hospitalizations, return to clinic, and/or ED encounters following scheduled ambulatory surgery. The timeframe for data collection was the first two years of a university sports medicine ambulatory surgery center’s operation. We hypothesized that the percentage of encounters would be low and primarily due to pain or post-operative complication.

Study design: Single center retrospective observational study.

Methods

Retrospective review was performed of all patients undergoing ambulatory surgery at a university ambulatory surgery center (ASC) during the first two years of the ASC’s operation (November 2016 - October 2018). Data including age, gender, CPT code, procedure performed, ASA classification, BMI, past medical history, and tobacco use was collected. Patients seeking care in the ED, inpatient, or outpatient setting within the first 24 hours after surgery were identified and the reasons for these encounters were categorized into one of three groups: 1) medical complication, 2) post-operative pain, or 3) other post-operative complication. Logistic regression models were used to assess risk factors for these encounters.

Results

A total of 4650 sports medicine procedures were performed at the university ambulatory surgery center during the study period. A total of 35 patients (0.75%) sought additional care within 24 hours of surgery. Medical complications were the primary reason

for seeking care (n=16, 45.7%). Patients in the first 24 hours of surgery tended to be older, had more medical co-morbidities, and were more likely to have undergone upper extremity (particularly shoulder) procedures. In the multivariable analysis, patients with higher ASA scores were more likely to seek additional care (p < 0.005), and there was a trend toward increased risk of seeking additional care with upper extremity surgery (p = 0.077).

Conclusion

Orthopaedic procedures done in an ambulatory surgical center result in a relatively low percentage of patients seeking additional care within the first 24 hours after surgery consistent with other reports in the literature. Upper extremity procedures, in particular those of the shoulder, may carry an increased risk of requiring medical treatment within 24 hours of surgery.

Clinical Relevance: The results of this study help surgeons and anesthesiologists understand the expected rate and factors that influence the need for emergency treatment and hospital admission in the first 24 hours following ambulatory surgery.

Key Terms: Unplanned admission, emergency treatment, ambulatory surgery center, orthopedic surgery, outpatient surgery