Influence of Skeletal Muscle Paralysis on Metabolism in Hypothermic Patients After Cardiac Arrest

The purpose of this study is to evaluate the impact of muscle relaxing drugs on the energy rate during hypothermia after cardiac arrest.

Mild hypothermia improves neurological outcome after cardiac arrest. Neuromuscular blockers are in use, together with analgesia and sedation, during the cooling process in many centers to prevent shivering. However, neuromuscular blockers are accused to be associated with various side effects causing serious harm and/or leading to prolonged ICU stay. Furthermore, the use of neuromuscular blockers may mask epileptic activity. Therefore, the advantages and disadvantages of neuromuscular blockers during therapeutic hypothermia need to be re-evaluated. Aim of this study is to investigate if continuous application of neuromuscular blockers is necessary to prevent shivering and thereby avoiding an increase in energy expenditure in patients during therapeutic hypothermia and rewarming after cardiac arrest (initial 72h).

Continuous application of neuromuscular blockers during therapeutic hypothermia. Bolus application of placebo in case of shivering.

Continuous application of placebo during therapeutic hypothermia. Bolus application of neuromuscular blockers in case of shivering.

Continuous application of Rocuronium (0.5 mg/kg body weight/hour). Bolus application of placebo in case of shivering.

Continuous application of placebo during therapeutic hypothermia. Bolus application of Rocuronium (0.5 mg/kg body weight) in case of shivering.

resting energy expenditure will be assessed with indirect calorimetry at different measurement time points: 12-24 h after initiation of mild hypothermia (33C°) during warming up (at 34.5°C) during warming up (at 36°C) during warming up (at 36.5°C - 37.5°C) normal Temperature, after 48 - 72 h after initiation of mild hypothermia

initial 72h after cardiac arrest at defined temperatures or timepoints: 1) 33°C 2) 34.5°C 3) 36 °C 4) 36.5 - 37.5 °C 5) after 48-72h

substrate oxidation rates will be assessed with indirect calorimetry at different measurement time points: 12-24 h after initiation of mild hypothermia (33C°) during warming up (at 34.5°C) during warming up (at 36°C) during warming up (at 36.5°C - 37.5°C) at normal Temperature, after 48 - 72 h after initiation of mild hypothermia

initial 72h after cardiac arrest at defined temperatures or timepoints: 1) 33°C 2) 34.5°C 3) 36 °C 4) 36.5 - 37.5 °C 5) after 48-72h

resting energy expenditure will be assessed with indirect calorimetry at different measurement time points: 12-24 h after initiation of mild hypothermia (33C°) during warming up (at 34.5°C) during warming up (at 36°C) during warming up (at 36.5°C - 37.5°C) normal Temperature, after 48 - 72 h after initiation of mild hypothermia

initial 72h after cardiac arrest at defined temperatures or timepoints: 1) 33°C 2) 34.5°C 3) 36 °C 4) 36.5 - 37.5 °C 5) after 48-72h

substrate oxidation rates will be assessed with indirect calorimetry at different measurement time points: 12-24 h after initiation of mild hypothermia (33C°) during warming up (at 34.5°C) during warming up (at 36°C) during warming up (at 36.5°C - 37.5°C) at normal Temperature, after 48 - 72 h after initiation of mild hypothermia

initial 72h after cardiac arrest at defined temperatures or timepoints: 1) 33°C 2) 34.5°C 3) 36 °C 4) 36.5 - 37.5 °C 5) after 48-72h

Inclusion Criteria: All patients receiving mild therapeutic hypothermia after cardiac arrest of presumed cardiopulmonary origin Exclusion Criteria: age < 18 cardiac arrest >6 hours before admittance at the hospital patients with known or clinically apparent pregnancy patients who reach our hospital with a body temperature below 35°C patients with known allergic reactions against rocuronium patients with a history of myasthenia gravis patients with obvious intoxication wards of the state/prisoners patients with known epileptic disease