Therapeutic Hypothermia in the Field

by Kevin T. Collopy, BA, FP-C, CCEMT-P, NREMT-P, WEMT, Sean Kivlehan, MD, MPH, NREMT-P, Scott R. Snyder, BS, NREMT-P
Created: June 1, 2012

How cardiac arrest patients benefit from early cooling

Figure 1: Fluid shifts increase the amount of fluid between cells and capillaries, making it more difficult for cells to receive oxygen and offload waste products.
Figure 1: Fluid shifts increase the amount of fluid between cells and capillaries, making it more difficult for cells to receive oxygen and offload waste products.
Fran Milnor

Figure 1: Fluid shifts increase the amount of fluid between cells and capillaries, making it more difficult for cells to receive oxygen and offload waste products.
Figure 1: Fluid shifts increase the amount of fluid between cells and capillaries, making it more difficult for cells to receive oxygen and offload waste products.

The selection of NMBAs varies widely and includes pancuronium, cisatracurium, rocuronium, vecuronium and atracurium. Nearly all NMBAs are free of major hemodynamic effects, which makes them safe for use during TH, but use caution with vecuronium and pancuronium, which both have active metabolites that accumulate in patients with renal dysfunction.⁷ Vecuronium and rocuronium are currently the most commonly administered NMBAs in prehospital care.

Conclusion

There are many devices and strategies for initiating prehospital therapeutic hypothermia. Administering 30 ml/kg of iced 4°C normal saline continues to be the most rapid and effective strategy. Systems without ALS providers can initiate TH by applying ice packs to the groin, neck and axilla to patients who experience ROSC.

Implementing a prehospital cardiac arrest protocol must be done in coordination with at least one hospital, because the in-hospital management of these cooled patients demands educated and prepared emergency department physicians, trained ICU nursing staff, pharmacologists, neurologists, cardiologists, pulmonologists and critical care intensivists.^3,4

Currently EMS systems only utilize TH for post-cardiac arrest patients, but in the future it may be reasonable to initiate on patients suspected of acute strokes or with STEMIs. If your system uses TH, consider the application of intra-arrest iced saline. If your EMS system does not utilize TH, consider a conversation with your medical director and the closest tertiary care center. Initiating therapeutic hypothermia requires coordinated medical care, but its use is a prime example of how a healthcare system can work together to benefit patients.

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