calcium chloride + half-normal saline

HCLS (High Calcium, Low Sodium) is an experimental fluid therapy regimen designed for the treatment of pulseless electrical activity (PEA) cardiac arrest. The therapy consists of a universal administration of 1 gram of calcium chloride followed by an intravenous drip of half-normal saline (0.45% sodium chloride). This combination is intended to create a hyponatremic and hypercalcemic environment to initiate "low sodium inotropy." By reducing extracellular sodium levels, the therapy aims to modulate the sodium-calcium exchange mechanism, thereby increasing intracellular calcium availability and enhancing mechanical cardiac contractility in patients where electrical activity is present but insufficient to generate a pulse. The regimen is currently being evaluated in the SPEAR (Surviving PEA in Roanoke) trial, a prospective, double-blind, randomized pre-hospital study conducted by Carilion Clinic and the Virginia Tech Carilion School of Medicine.

Other names

High Calcium, Low Sodium Crystalloid TherapyHCLS-Carol Bernier-pulseless electrical activitySPEAR trial regimen