Does obesity affect intraocular pressure during laparoscopic surgery?

Obesity is accepted as a risk factor for postoperative visual loss due to possible perioperative elevations in intraocular pressure. This study investigated whether intraocular pressure changes differed according to the body mass index of patients undergoing laparoscopic cholecystectomy. Thirty obese and 30 non-obese patients (body mass index cutoff point, 30 kg/m2) undergoing laparoscopic cholecystectomy were enrolled. Intraocular pressure was measured at baseline (T1), after induction of anesthesia (T2), 5 min after initiation of mechanical ventilation (T3), 5 min after pneumoperitoneum inflation (T4), 5 min after the patient was placed in the head-up position (T5), 5 min after deflation with the patient in the supine position (T6), and 5 min after extubation with the patient in the 30 degrees upright position (T7). The mean intraocular pressure values of the obese and non-obese groups were similar at T1 (16.60 ± 2.93 and 16.87 ± 2.85 mmHg respectively). In both groups, intraocular pressure decreased following initiation of anesthesia (T2) (p<0.001, T2 vs T1). Intraocular pressure values at T7 were significantly higher than those at T1 in the obese (20.38 ± 4.11 mmHg, p<0.001) and non-obese (20.93 ± 4.37 mmHg, p<0.01) groups. There were no significant differences between intraocular pressure values of obese and non-obese patients at any time point. Obesity is not correlated with intraocular pressure during short laparoscopic surgeries with the patient in the head-up position.