Impact of weight classes on feasibility, safety, and efficacy of awake craniotomy for brain lesions within eloquent areas.

Awake craniotomy is the gold standard to achieve maximal safe resection of brain lesions located within eloquent areas. There are no established guidelines to assess patient's eligibility for awake craniotomy by weight class. This study assesses feasibility, safety, and efficacy of awake surgery by weight classes through an observational, retrospective, single-institution cohort analysis (2010-2024) of 526 awake craniotomies. Comparison between normal weight (n = 276, 18.5 ≤ Body Mass Index (BMI) < 25 kg/m²), underweight (n = 34, BMI < 18.5 kg/m²), overweight (n = 158, 25 ≤ BMI < 30 kg/m²), and obese patients (n = 58, BMI > 30 kg/m²) were analyzed. Differences in weight classes in patients undergoing awake craniotomy: (1) were associated with a higher rate of intraoperative hypertension in underweight (8.8%), overweight (8.2%) and obese (8.2%) compared to normal weight patients (1.8%, p = 0.010); (2) did not increase the duration of the procedure (p = 0.754) but was associated with more frequent late awakening (> 30 min) in underweight (23.5%) compared to overweight (10.8%), obese (6.9%), and normal weight patients (8.7%, p = 0.044); (3) did not increase the occurrence of intraoperative epileptic seizures (p = 0.2) or intraoperative insufficient cooperation (p = 0.790); (4) did not impact resection rates (p = 0.165) and tumor residue (p = 0.559); (5) did not significantly increase surgery-related complications (p = 0,217) or duration of hospital stay (p = 0.099); (6) did not worsen the 6-month KPS score (p = 0.599), seizure control (p = 0.987), and time to return to work (p = 0.653). Our findings suggest that awake craniotomy is safe and feasible both in underweight and overweight patients, including severely obese patients, compared to patients with a normal weight.