Complications often precede CPR in surgical patients

A retrospective study of cardiac arrest and cardiopulmonary resuscitation (CPR) in surgical patients found that most arrests and resuscitations occurred postoperatively and after the patient developed complications. The results were published online in the January issue of Journal of the American Medical Association-Surgery.

Noting that most studies of CPR in surgical patients were over a decade old and focused solely on cardiac surgery patients, Hadiza S. Kazure, MD, of Stanford University in Palo Alto, Calif., and colleagues designed a study to determine common characteristics of surgical patients who experience arrest and CPR, and assess mortality factors. Using the American College of Surgeons-National Surgical Improvement Program (ACS-NSQIP) database, they captured information on surgical, nontrauma patients who were entered into the database between 2005 and 2010. Up to 250 hospitals across the U.S. contribute to the database. Of more than 1.3 million surgical cases in the dataset, the researchers analyzed the records of 6,382 surgical patients who experienced cardiac arrest and CPR.

The mean age of these patients was 68.2 years, with a mean of five comorbidities; only 2.8 percent of the CPR patients had no comorbidities. The overall incidence of cardiac arrest and CPR among surgical patients was one in 203 cases, but there was wide variation depending on comorbidity. Patients with zero comorbidities arrested at a rate of one in 2,174; with one comorbidity, the rate was one in 609, and patients with two or more comorbidities arrested at a rate of one in 95 cases.

A large majority of patients (86 percent) experienced cardiac arrest and CPR postoperatively, about half of those within three days of surgery. Postoperative complications were present in 77.6 percent of the CPR patients and 75.2 percent of those complications occurred before or on the day of the cardiac arrest.

The overall incidence of CPR was 0.492 percent, but there was considerable variation by specialty. The rate of cardiac arrest and CPR was highest for patients undergoing cardiac surgery (3 percent), followed by vascular surgery (1.31 percent) and thoracic surgery (1.14 percent). Patients undergoing gynecologic surgery had the lowest rates at 0.06 percent.

Overall mortality at 30 days was 71.6 percent. CPR patients survived to discharge in 30 days or less at a rate of 19.2 percent and 9.2 percent were alive but still hospitalized at postoperative day 30. Almost 2 percent of the patients who received CPR had do not resuscitate (DNR) orders.

After noting the high rates of mortality among these very sick patients, the researchers pointed out that their analysis indicated that despite their poor condition, many of the arrests and deaths in these patients may be preventable through prevention of complications and expedient diagnosis and treatment of complications when they occur.

In an invited critique of the study, Michael E. Zenilman, MD, of Johns Hopkins Medicine in Baltimore, agreed with the conclusions of Kazure et al. “Identification of which patients are at risk and early aggressive intervention with intensive medical and surgical care will decrease the need for CPR and its ultimate negative outcome,” he wrote. He asserted that at-risk patients would benefit from 24-hour monitoring by hospitalists and intensivists, and while acknowledging the cost of these interventions, suggested that “decreased downstream costs in intensive care and ultimately regionalization of patients at risk to appropriately staffed hospitals could contain these costs.”

Zenilman also considered the implications of the study on DNR orders. “The authors confirm that CPR in the postoperative period can succeed because most factors that lead to an arrest in the perioperative period are reversible. If those at risk are rapidly identified and appropriately treated, CPR in the early postoperative period is not futile,” he wrote. Therefore, Zenilman proposed that “DNR orders should not be active during this time.”