The Use of Neuromuscular Blockers to Prevent Shivering in the Setting of Postcardiac Arrest Targeted Temperature Management: A Narrative Review of an Off-Label Indication.

Targeted temperature management (TTM) has become a standard of care over the past two decades for the improvement in neurologic function and mortality in postcardiac arrest patients. There are various mechanisms by which hypothermia helps to improve these outcomes, one of which is by reducing oxygen requirements. Less established is the use of nondepolarizing neuromuscular blockers (NMBs) to prevent shivering during TTM. Shivering can be disadvantageous in this setting as it increases oxygen requirements, which TTM is actively trying to decrease, in an already oxygen-deprived system as well as generates heat making it difficult to maintain hypothermia. Whether NMBs can improve these outcomes is conflicting in the currently available literature and there lacks a consensus on their role in shivering management. The pharmacokinetic and pharmacodynamic responses of these agents may be altered in hypothermic patients, therefore, their standard of monitoring may be unreliable. The accurate dosing and administration of these agents also remain unclear, further complicated by the lack of a standard use protocol. Various studies have been conducted regarding the use of NMBs to prevent shivering in postcardiac arrest patients undergoing TTM; however, it remains an off-label indication requiring further investigation.