Cardiopulmonary arrest is an unexpected event in cardiac surgery patients in the postoperative period. Most studies have always advocated an expeditious conversion from closed-chest to open-chest CPR for cardiac arrest after cardiac surgery. The present study was designed to characterize the outcome of closed-chest compared with open-chest CPR, to define potential factors associated with unresponsiveness to closed-chest CPR, and to evaluate the need for open-chest CPR for this subgroup of patients.
A retrospective review was conducted for all cardiac surgical patients who underwent CPR for postoperative arrest between March 1995 and April 2002. Extensive data pertaining to preoperative, intraoperative characteristics, postoperative complications, and periarrest factors were collected. All data were analyzed using various statistical models.
Of the 6,094 patients, 45 (0.74%) patients had a cardiac arrest within seven postoperative days and required CPR. Twenty-four (53%) patients underwent only closed-chest CPR, whereas 21 (47%) patients underwent a conversion from closed-chest to open-chest CPR. Within the closed-chest CPR group, 17 (71%) were successfully resuscitated, while 7 (29%) died. Within the open-chest CPR group, only 3 (14%) were successfully resuscitated, while 18 (86%) died. A chi-squared test showed that the difference in the proportion of successful outcome between closed and open CPR was significant (p<0.001). The 17 patients who were successfully revived with closed-chest CPR were compared against the other 28 patients as a whole who did not respond to closed-chest CPR. Univariate predictors of failed closed-chest CPR included the presence of preoperative hypertension (p<0.001), the presence of severe angina (p=0.06), and urgent/emergent nature of surgery (p<0.005). Univariate predictors of successful closed-chest CPR included elective nature of surgery (p<0.05) and shorter aortic cross-clamp times (p<0.05).
The above results confirm that open-chest CPR has a poor overall outcome and may not be worthwhile for all cases unresponsive to closed-chest CPR.
Using the above outcome-associated factors may help the clinician determine which group of patients for whom it may be futile or worthwhile to convert to open-chest CPR.
Prashant Shah, None.