Outcome measures
The primary outcome was postoperative LOS defined as whole days from the day of surgery until discharge. According to China’s medical insurance policy, reimbursement can only be made if the LOS is more than one day, therefore, same day discharge has not yet become routine practice in our hospital. To adjust for the potential impact of the insurance policy and other nonmedical variables (i.e. social problem, patients’ concern, etc.) on LOS, a theoretical LOS was introduced, using the theoretical day of discharge, defined as the postoperative day when patients met the following predefined criteria: adequate pain control with oral analgesics, absence of vomiting or severe nausea, absence of body temperature ≥ 37.5°C, tolerance of solid food, and ambulation as preoperative.
Secondary outcomes included a numerical rating scale (NRS) score for postoperative pain, time to first flatus, simplified PONV impact scale score as previously described,13 postoperative 30-day complication (defined as any postoperative 30-day or in-hospital complication, according to the Clavien-Dindo classification)14, quality of life, readmission rate, and in-hospital cost. Quality of life was assessed on POD 3 with a Chinese-validated version of the Quality of Life-15 (QoR-15) questionnaire.15
We collected data via a secure dedicated website, and during hospitalization medical and nursing staff reported daily on patient status. The predefined discharge criteria were scored daily by an independent doctor blinded to group. Patients were systematically followed at an outpatient clinic and were evaluated for any complications or readmission occurring after discharge within 30 days of the operation.