NEJM Journal Watch
Patricia Kritek, MD, reviewing
Routine use of CPAP after abdominal surgery didn’t prevent pneumonia, reintubation, or death.
Respiratory complications (e.g., hypoxemia, pneumonia) are common after abdominal surgery and are thought to be related to postoperative atelectasis. Although adequate analgesia and incentive spirometry are important to minimize atelectasis, continuous positive airway pressure (CPAP) might be more effective. International investigators randomized nearly 5000 patients who had undergone open abdominal surgery (i.e., not laparoscopic) either to CPAP for at least 4 hours within 4 hours after surgery or to usual care. Most patients underwent either bowel resection or hepatobiliary surgery; very few patients who underwent stomach or esophageal surgery were included in the trial.
Incidence of pneumonia, reintubation, or death at 30 days was similar in the two groups, and these findings were consistent across multiple subgroups. Similar numbers of patients in each group were rehospitalized after discharge. Adverse events, most commonly claustrophobia and oronasal dryness, occurred in 9% of patients who received CPAP.
COMMENT
Routine use of CPAP to prevent postoperative atelectasis is not warranted. Patients in this study did tolerate positive pressure well, so using CPAP only with a clear indication (such as postoperative hypoxemia) is reasonable. Many surgeons worry about positive pressure impairing anastomotic healing after upper gastrointestinal surgeries; not enough of these patients were enrolled in the trial to comment on the safety of CPAP in this population.