Variability of the Impact of Risk Factors On Cardiac Outcomes Between Open and Laparoscopic Colectomy - Results From a NSQIP Database Study

Variability of the Impact of Risk Factors On Cardiac Outcomes Between Open and Laparoscopic Colectomy – Results From a NSQIP Database Study

Shankar R Raman, MD MRCS, Ilan Rubinfeld, MD FACS, Craig A Reickert, MD FACS FASCRS. Henry Ford Hospital, Detroit, MI

Introduction:
Laparoscopic colectomy is known to be associated with decreased overall complications when compared to open colectomy. The role of cardiac risk factors for complications as defined by the American Heart Association (AHA), in the setting of colectomy is not clear. We sought to examine and compare the risk factors for cardiac complications after laparoscopic and open colectomy based on the American College of Surgeons- National Surgical Quality Improvement Project (ACS-NSQIP) database.

Methods:
Using the ACS-NSQIP Participant Use File database, all patients undergoing both open and laparoscopic colectomy between 2005-2009 were identified based on CPT code. AHA Cardiac risk factors were mapped to existing NSQIP comorbidities such as history of ischemic heart disease, compensated or prior heart failure, cerebrovascular disease, diabetes mellitus and renal insufficiency were studied in both the laparoscopic and open group. Cardiac specific outcomes that were studied included myocardial infarction (postoperative and intraoperative), cardiac arrest (Intra-op and post op), congestive heart failure as well as death. Statistical analysis was done using SPSS 19 ( IBM, NY). Chi square tests, univariate and multivariate logistic regression models were used to study the impact of variables on outcome.

Results:
58448 colectomy patients were identified from the NSQIP database, of which 19062 (32.6%) underwent laparoscopic resections. 951 (1.6%) patients developed cardiac complications (101/19062 lap vs. 850/39386 open; Odds ratio 4.14, p<0.001). Emergency colectomy was performed in 10732 patients (672 laparoscopic). Incidence of cardiac complications among emergency colectomy (476; 4.4%) was significantly higher when compared to non-emergent cases (475; 1.0%) with odds ratio 4.6, p<.001

Increasing number of cardiac specific risk factors was significantly associated with worse outcomes from a cardiac standpoint (p<0.001) in both open and laparoscopic groups. Using regression models, the factors that were significantly associated with any cardiac complications were AHA risk factors, advanced age, male sex, emergency surgery, ASA class 4 or more, wound classification. In the laparoscopic colectomy group, emergency surgery and ASA class did not affect outcome whereas in the open group, only wound class was not significant.

Odds ratio and p values for variables impacting cardiac outcome
Variable	All colectomy Odds ratio (p)	lap colectomy Odds ratio (p)	Open colectomy Odds ratio (p)
AHA Risk Count	1.466 (<0.001)	2.083 (<0.001)	1.791 (<0.001)
Age >70 years	1.029 (<0.001)	1.047 (<0.001)	1.025 (<0.001)
Male	1.357 (<0.001)	1.838 (<0.005)	1.307 (<0.001)
Emergency	2.051 (<0.001)	1.021 (0.962)	1.897 (<0.001)
ASA 4 or more	2.576 (<0.001)	1.366 (0.362)	2.745 (<0.001)
Wound class	P<0.002	P= 0.027	P= 0.131

Conclusion:
Based on this large database study, the risk factors for cardiac complications after open colectomy and laparoscopic colectomy are different. Different mechanisms of pathophysiology may underlie this difference between open and laparoscopic colectomy. The risk factors as defined by AHA, advanced age, male sex are consistently associated with worse cardiac outcomes in both laparoscopic and open colectomy groups.

Session Number: Poster – Poster Presentations
Program Number: P137
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