Safety Profile of an Intracranial Multimodal Monitoring Bolt System for Neurocritical Care: A Single-Center Experience

Abstract Background Intracranial multimodality monitoring (iMMM) is increasingly used in acute brain injured patients; however, safety and reliability remain major concerns to its routine implementation. Methods We performed a retrospective study including all patients undergoing iMMM at a single European center between July 2016 and January 2020. Brain tissue oxygenation probe (PbtO2), alone or in combination with a microdialysis catheter and/or an 8-contact depth EEG electrode, was inserted using a triple lumen bolt system and targeting normal-appearing at risk brain area on the injured side, whenever possible. Surgical complications, adverse events and technical malfunctions, directly associated with iMMM were collected. A blinded imaging review was performed by an independent radiologist. Results 113 patients with 123 iMMM insertions were included for a median monitoring time of 9 [3–14] days. Of those, 93 (76%) patients had only PbtO2 probe insertion and 30 (24%) had also microdialysis and/or iEEG monitoring. SAH was the most frequent indication for iMMM (n = 60, 53%). At least one complication was observed in 67/123 (54%) iMMM placement, corresponding to 58/113 (51%) patients. Misplacement was observed in 16/123 (13%), resulting in a total of 6/16 (38%) malfunctioning PbtO2 catheters. Intracranial hemorrhage was observed in 14 iMMM placements (11%), of which one required surgical drainage. Five placements were complicated by pneumocephalus and 4 with bone fragments, none of these requiring additional surgery. No CNS infection related to iMMM was observed. Seven (6%) probes were accidentally dislodged and 2 probes (2%) were accidentally broken. Ten PbtO2 probes (8%) presented a technical malfunction after a median of 9 [ranges: 2–24] days after initiation of monitoring and 4 of them were replaced. Conclusions In this study, a high occurrence of complications related to iMMM was observed, although most of them did not require specific interventions and did not result in malfunctioning monitoring.