Perioperative cerebrospinal fluid lactate and glucose changes following intracranial surgery: A prospective observational cohort study.

Perioperative cerebral metabolism may change following intracranial surgery. This study aimed to evaluate perioperative changes in cerebrospinal fluid (CSF) lactate, glucose, and the lactate-to-glucose ratio and to examine the associations of changes in CSF lactate and glucose with clinical variables. This prospective observational cohort study included adults undergoing intracranial surgery. Paired CSF samples were obtained intraoperatively and 24 hours postoperatively from patients with clinically indicated postoperative CSF drainage. Changes in CSF lactate and glucose were evaluated in relation to surgical urgency, operative duration, and anesthesia duration. Paired intraoperative and 24-hour postoperative CSF measurements were available for 33 of the 50 patients (66.0%). Postoperatively, CSF lactate increased significantly from 2.2 [1.7-2.7] to 3.5 [2.8-4.2] mmol/L (P < .001, r = 0.78), whereas CSF glucose decreased from 4.2 [3.6-4.9] to 3.1 [2.5-3.8] mmol/L (P < .001, r = 0.72). The lactate-to-glucose ratio showed the largest effect size (P < .001, r = 0.84). Emergent procedures were associated with greater increases in CSF lactate than elective procedures (P = .012). Operative duration correlated with the change in CSF lactate (ρ = 0.52, P = .002). Anesthesia duration correlated with the change in CSF glucose (ρ = 0.45, P = .008). No hemorrhagic, infectious, or catheter-related complications associated with CSF sampling or drainage were observed. Intracranial surgery was associated with changes in CSF lactate, glucose, and the lactate-to-glucose ratio during the perioperative period. These routinely available CSF parameters may reflect cerebral metabolic stress following surgery. The findings should be considered exploratory and require confirmation in larger multicenter studies.