211 - Body Mass Index is Not Associated with Inpatient Pain Scores or Postop...

Oral Posters: MIS

Presented by: K. Kudaravalli - View Audio/Video Presentation (Members Only)


D. Massel(1), B. Mayo(1), D. Bohl(1), F. Hijji(1), A. Narain(1), K. Kudaravalli(1), K. Yom(1), K. Singh(1)

(1) Rush University Medical Center, Orthopaedic Surgery, Chicago, IL, United States


Introduction: Current literature reports successful outcomes following minimally invasive transforaminal lumbar interbody fusion (MIS TLIF); however, inpatient pain scores across body mass index (BMI) category have not been previously reported. The purpose of this study is to examine patient-reported inpatient pain scores in the immediate postoperative period by BMI category following MIS TLIF.

Methods: A prospectively maintained surgical database of patients who underwent a primary, one-level MIS TLIF for degenerative spinal pathology between 2010-2015 was reviewed. Patients were stratified according to BMI: normal weight (< 25 kg/m2), overweight (25-29 kg/m2), obese I (30-34 kg/m2), or obese II-III (≥35 kg/m2). Patients were assessed with regards to demographics and preoperative characteristics using a chi-squared test and ANOVA for categorical and continuous variables, respectively. The effect of BMI on surgical outcomes, narcotic consumption, and inpatient pain scores was analyzed using Poisson regression with robust error variance or linear regression adjusted for patient demographics and preoperative characteristics.

Results: A total of 305 patients were included in the analysis, of which 56 (18.4%) were normal weight, 110 (36.1%) were overweight, 68 (22.3%) were obese I, and 71 (23.3%) were obese II-III. Normal weight and obese II-III patients had lower percentage of smokers (Normal: 8.9%; Overweight: 17.3%; Obese I: 27.9%; Obese II-III: 12.7%; p=0.026), while a greater BMI was associated with having an increased comorbidity burden (Normal: 1.9; Overweight: 2.6; Obese I: 2.5; Obese II-III: 3.2; p=0.015), increasing mean operative time (Normal: 113.2; Overweight: 116.3; Obese I: 119.4; Obese II-III: 136.7 minutes; p=0.005), and a trend towards increasing hourly inpatient VAS pain scores on POD 0 (Normal: 5.1; Overweight: 5.3; Obese I: 5.6; Obese II-III: 5.6; p=0.322), POD 1 (Normal: 4.5; Overweight: 4.9; Obese I: 4.9; Obese II-III: 5.3; p=0.194), and POD 2 (Normal: 4.6; Overweight: 4.7; Obese I: 5.0; Obese II-III: 5.4; p=0.053) as well as OME consumption (Normal: 2.6; Overweight: 2.6; Obese I: 2.7; Obese II-III: 3.1; p=0.066) on POD 2, although not statistically significant.

Conclusions: The results of this study suggest patients with a greater BMI do not report increased pain or require increased narcotic consumption in the immediate postoperative period despite prolonged operative times. As such, the postoperative analgesia protocol should not differ across BMI stratifications.

Table 1

Table 2