Hypoventilation in the PACU is associated with hypoventilation in the surgical ward: Post-hoc analysis of a randomized clinical trial

• Published in: Journal of clinical anesthesia 2023-02, Vol.84, p.110989-110989, Article 110989
• Main Authors: Rivas, Eva, Cohen, Barak, Saasouh, Wael, Mao, Guangmei, Yalcin, Esra K., Rodriguez-Patarroyo, Fabio, Ruetzler, Kurt, Turan, Alparslan
• Format: Article
• Language: English
• Subjects: Abdomen; Abdominal surgery; Adult; Anesthesia; Anesthesia, General - adverse effects; Body mass index; Hospital costs; Humans; Hypotheses; Hypoventilation; Hypoventilation - epidemiology; Hypoventilation - etiology; Monitoring, Physiologic; Narcotics; Opioids; Postoperative; Postoperative Period; Prospective Studies; Surgical ward; Ventilation
• ISSN: 0952-8180; 1873-4529
• DOI: 10.1016/j.jclinane.2022.110989

To evaluate the association between early postoperative hypoventilation in the last hour of the post-anesthesia care unit (PACU) stay and hypoventilation during the rest of the first 48 postoperative hours in the surgical ward. Sub-analysis of a clinical trial. PACU and surgical wards of a single medical center. Adults having abdominal surgery under general anesthesia. Monitoring with a respiratory volume monitor from admission to PACU until the earlier of 48 h after surgery or discharge. The exposure was having at least one low minute-ventilation (MV) event during the last hour of PACU stay, defined as MV lower than 40% the predicted value lasting at least 1 min. The primary outcome was low MV events lasting at least 2 min during the rest of the first 48 postoperative hours, while in the surgical ward. The secondary outcome was the rate of low MV events per monitored hour. Data of 292 patients were analyzed, of which 20 (6.8%) patients had a low MV event in PACU. Low MV events in the surgical ward were found in 81 (28%) patients. All patients who had low MV events in PACU had events again in the ward, while 61/272 (22%) had an event in the ward but not in PACU. The incidence rate of low MV events per hour was 24 (95% CI: 13, 46) among patients having an event in the PACU, and 2 (1, 4) among those who did not. In adults recovering from abdominal surgery, events of hypoventilation during the first postoperative hour are associated with similar events during the rest of the first 48 postoperative hours, with positive predictive value approaching 100%. Sixty-one patients had ward hypoventilation that was not preceded by hypoventilation in PACU. •Postoperative respiratory depression is common and it might result in critical events such as death or severe brain injury.•Continuously monitoring all patients throughout their postoperative course is challenging.•A respiratory volume monitor was used in adults after abdominal surgery starting in PACU.•All patients experiencing hypoventilation in PACU also had hypoventilation in the surgical ward.•PACU hypoventilation had positive and negative predictive values of 100% and 78% to ward hypoventilation.