Summary

This study aimed to utilize the National Surgical Quality Improvement Program database to determine if body mass index (BMI) is associated with 30-day postoperative complications following arthroscopic surgery.

Abstract

Purpose

The obesity epidemic in the United States has made the body mass index (BMI) an important preoperative consideration when evaluating a patient for elective surgery.  This study aimed to utilize the National Surgical Quality Improvement Program (NSQIP) database to determine if body mass index (BMI) is associated with 30-day postoperative complications following arthroscopic surgery. 

Methods

The NSQIP database was queried for elective arthroscopic procedures of the knee, hip and shoulder. A retrospective cohort analysis was conducted with patients categorized by BMI class. Overall 30-day morbidity, mortality, readmission, reoperation and venothromboembolism (VTE) were compared using univariate analyses and binary logistic regressions to ascertain the adjusted effect of BMI, with and without diabetes, on morbidity, readmission, reoperation and VTE. The morbid event rate per BMI category was analyzed for knee and shoulder procedures individually, hip arthroscopy's morbid event rate, however, was too low for univariate analysis.

Results

There were 141,335 patients who met criteria. The overall morbidity rate was 0.92% and the most common complications were deep vein thrombosis (382 cases, 0.27%), superficial surgical site infection (234 cases, 0.17%), urinary tract infection (185 cases, 0.13%), and pulmonary embolism (151 cases, 0.11%). The remainder of the complications occurred in less than 1/1000 cases. Obesity class III with diabetes was a risk factor for morbidity (OR 1.522, 95% CI, 1.101-2.103) and readmission (OR 2.342, 95% CI, 1.998-2.745) following all procedures, while obesity class I was protective towards reoperation (OR 0.687, 95% CI, 0.485-0.973). Underweight patients were at higher risk for morbidity following shoulder arthroscopy (OR 3.776, 95% CI, 1.605-8.883), as were the class I obese (OR 1.421, 95% CI, 1.010-1.998) and class II obese (OR 1.726, 95% CI, 1.159-2.569). BMI did not significantly affect morbidity following knee arthroscopy. VTE risk factors included being overweight (OR 1.474, 95% CI, 1.088-1.996) or diabetic with class I obesity (OR 1.469, 95% CI, 1.027-2.101).

Conclusion

Arthroscopic procedures are safe with very low complication rates. However, underweight, class I and class II obese patients are at higher risk for morbidity following shoulder arthroscopy, and diabetic patients with class III obesity are at higher risk for morbidity and readmission following all arthroscopy. Because BMI is a modifiable risk factor, these patients should be evaluated carefully before being considered for outpatient arthroscopic surgery.

Level of Evidence: Level III, retrospective comparative study