Development of an Improved Risk Calculator for Complications in Proctectomy

Abstract

Rectal surgery is associated with high complication rates, but tools to prospectively define surgical risk are lacking. Improved preoperative risk assessment could better inform patients and refine decision making by surgeons. Our objective was to develop a validated model for proctectomy risk prediction. We reviewed non-emergent ACS-NSQIP proctectomy data from 2005-2011 (n=13,385). Logistic regression identified variables available prior to surgery showing independent association with 30-day morbidity in 2010-2011 (n=5,570). The resulting risk model's discrimination and calibration were tested against the NSQIP-supplied morbidity model, and performance was validated against independent 2005-2009 data. Overall morbidity for proctectomy in 2010-2011 was 40.2%; significantly higher than the 23.0% rate predicted by the NSQIP-provided general and vascular surgery risk model. Frequent complications included bleeding (16.3%), superficial infection (9.2%), and sepsis (7.4%). Our novel model incorporating 17 preoperative variables provided better discrimination and calibration (p<0.05) than the NSQIP model, and was validated against 2005-2009 data. A web-based calculator makes this new model available for prospective risk assessment. We conclude that the NSQIP-supplied risk model underestimates proctectomy morbidity and that this new, validated risk model and risk-prediction tool (http://myweb.uiowa.edu/sksherman) may allow clinicians to counsel patients with accurate risk estimates using data available in the preoperative setting.

Differences in Short-term Outcomes Among Patients Undergoing IPAA With or Without Preoperative Radiation

“…To compare overall preoperative risk between patient groups, average Iowa Rectal Surgery Risk Model morbidity probabilities were determined for the groups receiving and not receiving preoperative radiation. 19 The group receiving preoperative radiation had a significantly lower average predicted morbidity probability based on preoperative characteristics (30.2% vs. 34.3%, p<0.001), indicating a slightly better general preoperative risk profile among patients receiving preoperative radiation.…”

“…18, 19 Included were non-emergent ileal pouch-anal anastomosis procedures (CPT codes 44158, 44211, 45113, and 44157) performed by general and colorectal surgeons at NSQIP-participating hospitals. Recorded postoperative diagnoses were categorized as cancer, inflammatory bowel disease (IBD), or “other,” when cancer or IBD were not explicitly specified.…”

“…Overall preoperative risk was assessed using estimates from the validated Iowa Rectal Surgery Risk Model. 19 …”

Risk Calculators Predict Failures of Knee and Hip Arthroplasties: Findings from a Large Health Maintenance Organization

“…Although risk calculators have been created for various diagnoses, procedures, and outcomes, and are used in a range of settings [2,3,5,6,16,18,22,26,35,[42][43][44][45], risk calculators for total joint arthroplasties have not been developed and fully integrated in large healthcare settings. One risk calculator for periprosthetic joint infection and mortality after THA has been developed however, it was developed only for the Medicare population [5].…”

Examining the Validity of the Acs-Nsqip Risk Calculator in Plastic Surgery: Lack of Input Specificity, Outcome Variability and Imprecise Risk Calculations

“…Surgical morbidity that is monitored is the same for all procedures across all specialties, and is not specific for concerns within plastic surgery. Its external validity has been tested in other subspecialties,6 which have found that the predictor overestimates risks of complications 7 8. While its external validity has been tested in other subspecialties, it has not yet been validated in plastic surgery procedures.…”