The impact of anesthetic modality and cardiopulmonary bypass flow type on intraoperative intraocular pressure during coronary artery bypass grafting: A prospective, randomized controlled trial.

Intraocular pressure (IOP) is an indirect marker of ocular perfusion and is critical during coronary artery bypass grafting (CABG) due to potential hemodynamic instability. The combined effects of anesthetic modality (sevoflurane vs propofol-based total intravenous anesthesia [TIVA]) and cardiopulmonary bypass (CPB) flow type (pulsatile vs nonpulsatile) on intraoperative IOP during CABG are not well established. This prospective, randomized controlled trial included 160 patients undergoing CABG, randomized into four groups (n = 40 each): Sevoflurane + pulsatile CPB (SP), sevoflurane + nonpulsatile CPB (SN), TIVA + pulsatile CPB (TP), and TIVA + nonpulsatile CPB (TN). Patients with preexisting ocular conditions were excluded. IOP was measured using a Tono-Pen Avia at four time points: before induction, after induction, after CPB initiation, and at the end of surgery. Statistical analysis included one-way analysis of variance, Tukey post hoc testing, and chi-square tests. Baseline characteristics and IOP values were comparable across groups. After induction, the TIVA groups (TP and TN) showed a significant reduction in IOP (mean difference -3.5 mm Hg; P < .001) compared with the sevoflurane groups. Upon CPB initiation, IOP increased in all groups, most prominently in the SN group (P < .01). Pulsatile flow was associated with significantly lower IOP values than nonpulsatile flow (P < .01), irrespective of anesthetic modality. The TP group exhibited the most stable IOP profile throughout surgery (P < .05). No acute glaucoma or serious ocular complications were observed. Propofol-based TIVA produced a greater reduction in IOP after induction, and pulsatile CPB contributed to a more stable intraoperative IOP profile during CABG compared with sevoflurane anesthesia and nonpulsatile CPB, respectively. Although IOP fluctuations remained within subclinical limits, these findings suggest that TIVA combined with pulsatile CPB may offer advantages in maintaining ocular hemodynamic stability, particularly in high-risk patients.