Potential Complications

Although the use of therapeutic hypothermia is strongly supported by the existing literature, clinicians must be careful to use it in the correct patient population and be aware of potential problems arising from its use. Cooling has the effect of immune suppression, making it a relative contraindication in patients with suspected sepsis. Overcooling also will lead to more potential complications from induced coagulopathies. Even in the target temperature range, complications from ROSC and hypothermia are numerous and include shivering, fever, hypotension, hyperglycemia, electrolyte abnormalities (especially potassium), bradycardia, and continued cardiac ischemia. Failure to monitor for and address these adjunctive conditions can lead to morbidity and mortality despite appropriate initiation of therapeutic hypothermia.

Practical Matters

Creating a successful therapeutic hypothermia protocol at your hospital is a complex undertaking requiring concerted efforts by many constituents. Emergency physicians and nurses, critical care nurses, cardiologists, neurologists, intensivists, and hospital administrators should be involved in the decisions about what equipment to purchase and in the development of your hospital’s specific protocol.

Head-to-head comparisons of the commonly used systems for cooling a patient have not showed a definitive advantage of any particular device. The start-up costs range from the cost of ice packs to expensive comprehensive commercial devices, which cost anywhere between $5,000 and $50,000, plus the cost of disposable accessories per patient use. Choose the device

that would best serve your hospital’s cardiac, neurologic, and emergency patients at the price point and convenience point that fits your needs. Remember that therapeutic cooling is a resource-intensive intervention, and some hospitals may elect to transfer eligible patients to centers providing higher levels of care.

Summary

Patients who have witnessed sudden cardiac arrest and are comatose after return of spontaneous circulation can benefit from therapeutic hypothermia. Initial studies of therapeutic hypothermia are promising, and future developments will improve our understanding of the best methods of cooling.

Significant hurdles to implementing a program include intensive use of resources, institutional commitment from multiple specialties for continued patient care, potential complications during cooling such as coagulopathy and hypotension, and the cost of the various devices. Multiple studies showing impressive results in favorable neurologic outcomes for the proper patients make the difficult task of developing a program worthwhile.

References

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