Cerebral stimulation following succinylcholine in dogs

Area of Science:

• Anesthesiology and Pharmacology
• Neuroscience
• Critical Care Medicine

Background:

• Succinylcholine (SCh) is a depolarizing neuromuscular blocking agent.
• Its effects on cerebral hemodynamics and intracranial pressure (ICP) require further elucidation, especially under anesthesia.

Purpose of the Study:

• To investigate the impact of intravenous succinylcholine (SCh) on electroencephalogram (EEG), cerebral blood flow (CBF), cerebral metabolic rate (CMRO2), ICP, central venous pressure (CVP), and mean arterial pressure (MAP).
• To assess the relationship between SCh administration and changes in cerebral physiological parameters in an animal model.

Main Methods:

• Halothane-anesthetized dogs (1.0 MAC) received intravenous succinylcholine (SCh) or a placebo.
• Measurements included EEG, CBF, CMRO2, ICP, CVP, and MAP.
• Physiological parameters were monitored before and after SCh administration.

Main Results:

• SCh induced EEG arousal in most dogs and significantly increased CBF.
• A transient but significant rise in ICP was observed, correlating with peak CBF.
• PaCO2 levels increased post-SCh, while CVP, MAP, and CMRO2 remained unchanged.

Conclusions:

• Intravenous SCh administration can lead to increased CBF and ICP in anesthetized dogs.
• The observed EEG arousal suggests a potential central effect of SCh.
• These findings have implications for the use of SCh in patients with compromised cerebral circulation or elevated ICP.