Total Psoas Area is a Measure for Deconditioning in Colorectal Surgery Patients

Introduction Physical fitness is an important prognostic indicator for surgical outcomes. An objective measure of deconditioning is needed to determine patient fitness. This study aims to describe a methodology to standardize psoas measurements and correlate them with postoperative outcomes. Methods After obtaining IRB approval, the ACS-NSQIP database was queried for patients over 18 years, undergoing colectomies for non-trauma indications from 1/1/2013 to 12/31/2018. Upon CT imaging, the psoas muscle was identified at the lumbosacral joint. Imaging software calculated the total cross-sectional area of the left and right psoas muscle and was normalized by dividing by height squared to achieve our Total Psoas Index (TPI) in cm2/m2. Results 1173 patients met study criteria; all had TPI calculated. A TPI equal to or below the gender-specific 25th percentile defined sarcopenia. In total, 151 females (24.6%) and 137 males (24.5%) were classified as sarcopenic. TPI was significantly associated with multiple NSQIP 30-day outcomes and mortality in our study population. Conclusions Measuring TPI at the lumbosacral joint is an appropriate method for determining sarcopenia.