Jugular Bulb Oxygen-Desaturation Episodes During Functional Cerebral Hemispherotomies

Abstract

To the Editor: Hemispherotomy, a modified functional hemispherectomy, is indicated in catastrophic unilateral epileptic syndromes where the substrate lies upon a diffuse hemispheric disease, with preservation of the contralateral hemisphere. Few published data describe anesthetic monitoring during this procedure (1–3). Monitoring jugular bulb venous oxygen saturation (Sjo2) in the healthy hemisphere gives useful information for maintaining adequate cerebral perfusion pressure and for setting the best ventilator characteristics to avoid hyperventilation and cerebral vasoconstriction (4,5). We report our experience with five patients with diffuse hemispheric disease, who underwent cerebral hemispherotomy. Because we continuously monitored Sjo2, we were able to detect and correct several episodes of severe desaturation. In each patient we inserted a fiberoptic oximetry catheter (Oximetrix, Abbott Critical Care Systems, North Chicago, IL) through the jugular vein ipsilateral to the healthy hemisphere, allowing us to continuously record Sjo2. In all patients, we detected several episodes of Sjo2 < 50% during neurosurgical procedures lasting from 7 h to 9 h 30 min. Representative episodes are shown in Table 1. These episodes were caused by modest hyperventilation, slight decreases in arterial blood pressure, or postural changes (e.g., reverse Trendelenburg position). Sjo2 normalized after we had several simultaneous adjustments: diminishing ventilation, increasing Fio2, and increasing arterial blood pressure. If we had not monitored Sjo2, we would have missed the impaired cerebral oxygenation, potentially resulting in intraoperative cerebral ischemia, increased postoperative morbidity, and impaired neurological outcome. All patients had good neurological outcomes.Table 1: Measured Hemodynamic and Respiratory VariablesNeus Fàbregas, MD, PhD Ivan Bel, MD Lydia Salvador, MD Ricard Valero, MD, PhD Enrique Carrero, MD Anesthesiology Department Hospital Clínic i Provincial de Barcelona University of Barcelona Barcelona, Spain [email protected] Jordi Rumià, MD Neurosurgical Department Hospital Clínic i Provincial de Barcelona University of Barcelona Barcelona, Spain