What are the exclusion criteria for therapeutic hypothermia (TH) protocol after cardiac arrest?

From the Guidelines

Exclusion criteria for cooling protocol after cardiac arrest include active bleeding, severe sepsis, pregnancy, terminal illness with limited life expectancy, and pre-existing severe neurological disability, as these conditions may be worsened by cooling or have uncertain effects, as noted in the most recent guidelines 1.

Key Considerations

• Patients with hemodynamic instability requiring high-dose vasopressors, refractory shock, or those with a core temperature below 30°C (severe hypothermia) should also be excluded from cooling protocols due to potential adverse effects on cardiovascular stability and coagulation, as suggested by previous studies 1.
• Additional contraindications include known coagulopathy, recent major surgery within 14 days, and traumatic brain injury with intracranial hemorrhage, as these conditions may be exacerbated by cooling, according to the evidence 1.
• Targeted temperature management should not be implemented in patients who have a do-not-resuscitate order or when cardiac arrest was caused by trauma, as the benefits of cooling may not outweigh the risks in these scenarios, as indicated by the guidelines 1.

Rationale

The rationale behind these exclusions is that cooling can exacerbate bleeding by impairing coagulation, worsen infection by suppressing immune function, and may be futile in patients with poor baseline neurological status or limited life expectancy, as discussed in the literature 1. In pregnant patients, the effects on the fetus are uncertain, and patients with severe hemodynamic compromise may experience worsening cardiovascular instability with induced hypothermia, which can reduce cardiac output and cause arrhythmias, as noted in the studies 1. Each case should be evaluated individually, weighing the potential neurological benefits against these risks, as recommended by the most recent guidelines 1.

From the Research

Exclusion Criteria for Cooling Protocol after Cardiac Arrest

• The exclusion criteria for cooling protocol after cardiac arrest are not explicitly stated in the provided studies, but certain conditions and patient characteristics may be considered as exclusion criteria based on the study findings:
  • Presence of do-not-resuscitate orders 2
  • Unstable cardiac dysrhythmia 3
  • Acute myocardial infarction 3
  • Age, although it is not recommended to exclude patients from aggressive care solely based on age 2
• Certain patient populations may require special consideration when implementing a cooling protocol, such as:
  • Elderly patients, who may have more comorbidities and be more likely to have do-not-resuscitate orders 2
  • Patients with non-shockable rhythms, who may not benefit from therapeutic hypothermia to the same extent as patients with shockable rhythms 4, 5
• The decision to exclude a patient from a cooling protocol should be made on a case-by-case basis, taking into account the individual patient's characteristics, medical history, and current condition.

Patient Characteristics and Cooling Protocol

• Patient characteristics, such as initial heart rhythm, witnessed arrest, bystander cardiopulmonary resuscitation, and total ischemic time, can affect the outcome of cardiac arrest and the effectiveness of the cooling protocol 4, 2
• The presence of comorbidities, such as sustained hyperglycemia, can also impact the patient's response to the cooling protocol 2

Cooling Protocol and Outcomes

• The cooling protocol can affect patient outcomes, including survival and neurologic recovery 6, 4, 5, 3
• The use of targeted temperature management, including therapeutic hypothermia, can improve outcomes in patients with out-of-hospital cardiac arrest with an initial shockable rhythm 4, 5