The Anaesthetic Biobank Of Cerebrospinal Fluid: A Repository For Neuroscientific Research

Abstract

Background: The pathophysiology of numerous central nervous system disorders remains poorly understood. Biochemical analyses of cerebrospinal fluid (CSF) may identify novel biomarkers and help illuminate the neurobiology of common neuropsychiatric disorders. Studies of CSF biomarkers have so far generally included small numbers of patients with neurodegenerative diseases without adequate control groups. The Anaesthetic Biobank of Cerebrospinal Fluid (ABC) is an ongoing project in which we are storing CSF collected from patients undergoing spinal anaesthesia, a relatively neurologically healthy population. Our aim is to provide reference values for CSF-based biomarkers and to investigate associations between candidate markers and neuropsychiatric symptoms. We here present our methods and initial technical results.Methods: All patients ≥ 18 years scheduled for elective surgery under spinal anaesthesia are invited to participate, except for patients scheduled for caesarean section. A Montreal Cognitive Assessment (MoCA) and screening neurological examination are performed preoperatively. During intravenous cannulation, 20 ml blood is collected. During the spinal puncture, prior to intrathecal local anaesthetic administration, 10 ml of CSF is aspirated. Sensory block height is measured 10 minutes after spinal injection. A portion of the blood and the first 2 ml of CSF is sent for routine laboratory analyses. The remaining material is stored at -80°C. Relevant clinical, surgical and anaesthetic data are registered. A subset of patients have completed questionnaires on somatic and mental health (depression, anxiety and stress).Results: Four-hundred-fifty patients (58% male; median age: 56 years, IQR: 37 - 67) were enrolled between October 2016 and March 2020. Body mass index (BMI) ranged from 18 to 51 with a median of 27 kg/m2. Almost half of patients were ASA status I and were discharged home on the day of surgery. MoCA scores ranged from 14 to 30 and 60% of patients had a MoCA score ≥ 26. Blood was collected in 445 (99%) of patients. The planned spinal anesthetic procedure was not attempted for various reasons in eleven patients, in fourteen patients the spinal puncture failed and in twelve patients CSF aspiration was unsuccessful. In the remaining 413 patients, mean CSF volume aspirated was 9.3mL (range 0.1 - 13.0). CSF aspiration required a mean (range) of 2 minutes (1 - 10). A vasovagal response occurred in 7% of all patients, the spinal block was insufficient in 3% of patients and post-dural puncture headache was reported for 3 patients. Median (IQR) [range] block height was T8 (T6 - T10) [L5 - C4]. Type of local anaesthetic used had a significant effect on the extent of block (isobaric bupivacaine T6, hyperbaric bupivacaine T8, hyperbaric prilocaine T9; p<0.001).Conclusion: Banking of CSF from a surgical population is ongoing and feasible and does not appear to pose any significant additional risks to participating patients as sensory block height and the incidence of complications were consistent with that reported in earlier studies. Our large sample size, standardized sampling methods and extensive patient phenotyping provide excellent conditions for future neuroscientific research. So far, we are studying the relationships among CSF biochemistry and block height, and also with depression scores, and remain open to suggestions for collaborations with other interested groups.Copyright © 2020 American Society of Anesthesiologist