Intraoperative cerebral desaturation during low-central-venous-pressure hepatectomy with intermittent Pringle maneuver: a case report.

Background: Intraoperative cerebral desaturation has been associated with postoperative neurocognitive complications and may represent a potentially modifiable perioperative risk factor. The Pringle maneuver, or intermittent portal triad clamping, is routinely used to minimize blood loss during low-central-venous-pressure (LCVP) hepatectomy; however, its real-time relationship with cerebral oxygenation remains insufficiently characterized. We report a case providing high-resolution, time-locked documentation of abrupt bilateral regional cerebral oxygen saturation (rSO₂) decline during repeated intermittent hepatic inflow occlusion under LCVP conditions, followed by transient CAM-positive postoperative delirium. Case presentation: A 51-year-old female underwent elective right hepatectomy for hepatocellular carcinoma under low-central-venous-pressure (CVP < 5 cm H₂O) anesthesia. Bilateral rSO₂ was continuously monitored using near-infrared spectroscopy (NIRS) during eight cycles of intermittent Pringle maneuver (10-15 min occlusion/5 min reperfusion). rSO₂ showed a progressive downward trend across repeated clamping cycles, reaching a nadir of 33% on the left and 30% on the right 6 min into the eighth occlusion, coinciding with a CVP decrease to 0.9 cm H₂O despite MAP remaining above 65 mmHg. The patient developed transient CAM-positive, predominantly hypoactive postoperative delirium from POD 1 to POD 3, documented during the morning assessments on POD 1 and POD 2 and during the evening assessment on POD 3. The delirium resolved by POD 4 without pharmacological treatment. Structured follow-up at 1 month revealed subtle impairments in executive function and episodic memory (MoCA-Basic 25/30), which normalized to baseline (28/30) at the 3-month assessment. Evaluations at 6 months and 1 year demonstrated sustained neurocognitive recovery with no functional deficits or oncological recurrence. Conclusion: This case suggests that intermittent portal triad clamping under LCVP conditions may be associated with clinically important cerebral desaturation, even when conventional mean arterial pressure targets appear acceptable. The observation highlights the limitation of relying solely on systemic arterial pressure to infer cerebral oxygenation during high-risk hepatectomy. NIRS may serve as a useful adjunctive monitor for detecting otherwise unrecognized cerebral desaturation and may help guide timely multidisciplinary responses. However, the relationship between intraoperative cerebral desaturation and postoperative delirium in this case should be interpreted as hypothesis-generating rather than causal.