Postsurgical CPR Complications Are Preventable

Steven Fox

January 17, 2013

Surgical patients who receive postoperative cardiopulmonary resuscitation (CPR) have a high mortality rate, but a new study shows that prevention, expedient detection of complications, and aggressive interventions to avoid CPR could greatly improve outcomes.

That is the primary conclusion from a retrospective cohort study that used data from 2005 to 2010 from the American College of Surgeons–National Surgical Quality Improvement Program.

The research was presented in an article authored by Hadiza Kazaure, MD, from the Department of General Surgery, Stanford University, Palo Alto, California, and colleagues, published in the January issue of JAMA Surgery (formerly Archives of Surgery).

The authors write, "Not all cardiac arrests have the same origin: out-of-hospital arrest usually results from an acute onset of cardiac arrhythmia, whereas up to 14% of in-hospital arrests are preceded by complications, such as hypotension, metabolic or electrolyte disturbances, and respiratory insufficiency, and are potentially preventable or modifiable."

A number of studies have assessed surgical patients who experience cardiac arrest and undergo CPR, the authors note. However, because of the various limitations of those studies, "the overall incidence, characteristics, and outcomes of surgical patients who receive CPR are largely unknown."

These researchers conducted a retrospective analysis of the data on 6382 surgical patients (mean age, 68 years) who underwent CPR in-hospital. Their aim was to identify factors associated with 30-day mortality, especially factors that might be targeted to improve patient outcomes.

They found that 85.9% of CPRs took place postoperatively, with about half happening within 5 days after surgery.

The overall incidence of CPR in the population studied was 1 in 203 but varied significantly by medical specialty. For example, the incidence of CPR in patients who underwent cardiac surgery was 1 in 33, whereas for general surgery it was 1 in 258.

Mortality rates, too, varied by specialty, ranging from 45.0% to 74.5%.

The presence of comorbid conditions also had a significant effect on mortality (58.7% for no comorbiditiy, 63.1% for 1 comorbidity, and 72.8% for ≥2 comorbidities; P < .001).

Of patients who required CPR, 77.6% experienced a complication, about three quarters of which occurred either before or on the day CPR was administered.

Septicemia was the most common complication, accounting for 26.7% of the total. "It is a significant finding that more than 1100 patients in this study who were operated on without evidence of preoperative sepsis experienced postoperative sepsis or shock, and of these, 790 died," the authors write.

Other common complications included ventilator dependence (22.1%), significant bleeding (13.9%), and renal impairment (11.9%).

For the cohort as a whole, 30-day mortality was 71.6%. Only 19.2% of patients survived to be discharged from hospital in 30 days or less, and 9.2% of patients were alive but remained hospitalized a month after surgery.

Effect of DNR Orders

After adjusting for more than 30 risk factors in a multivariate analysis, several factors remained independently associated with poorer survival: advanced age, a preexisting do-not-resuscitate (DNR) order, renal impairment, metastatic cancer, preoperative sepsis, and postoperative cardiac arrest. An American Society of Anesthesiologists class of 5 was most strongly associated with a poorer chance of survival.

The authors conclude, "Complications commonly precede arrest; prevention or aggressive treatment of these complications may potentially prevent CPR and improve outcomes. These data could aid discussions regarding advance directives among surgical patients."

In an accompanying invited critique, Michael Zenilman, MD, from the Department of Surgery, Johns Hopkins Medicine, Bethesda, Maryland, writes, "Surgical patients who need CPR can be saved. Therefore DNR orders should not be active during this time."

He notes that the American College of Surgeons has published a position statement on DNR in surgical settings and that he believes that policy should be incorporated into all hospitals' surgical protocols.

"They suggest modification of DNR orders in the perioperative period via a 'required reconsideration of advance directives,' " he writes, adding, "Bluntly, temporarily rescind the order."

The authors and commentator have disclosed no relevant financial relationships.

JAMA Surg. 2013;148:14-21. Article full text, Critique extract