Skeletal Muscle Paralysis in Hypothermic Patients After Cardiac Arrest

Summary

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. Since neuromuscular blockers are accused to be associated with various side effects causing serious harm and/or leading to prolong ICU stay. So economical use seems to be reasonable. Furthermore, the use of neuromuscular blockers may mask epileptic activity. Therefore, post hypoxic seizures might remain undetected.

Aim of this study is to investigate if a continuous application of neuromuscular blockers is necessary to prevent shivering and thereby avoid the counter regulation to achieve the target temperature as soon as possible in mild hypothermic therapy after cardiac arrest.

A single center (university hospital) study. Randomized, double blinded, double dummy study design. Eligible are all adult patients after successful resuscitation due to cardiac arrest of presumed cardiac origin.

All patients receiving mild therapeutic hypothermia after cardiac arrest of presumed cardiopulmonary origin will be included.

Patients \<18 years, 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 and patients with known epileptic disease will be excluded.

Primary outcome:

Shivering episodes will be scored with the Shivering Assessment Scale.

Secondary outcome:

Total doses of rocuronium, time to target core temperature of 33°C, dissipated energy and total energy needed during the cooling period will be compared between the two groups.

Changes in basal metabolism and depth of relaxation will be ascertained. Furthermore, serum levels of midazolam, fentanyl, rocuronium and stress hormones will be measured.

Train-of-four will be performed to assess the depth of relaxation. Sedation will be monitored via bispectral index; measurement of metabolic activity will be evaluated using indirect calorimetry. Additionally, EEG will be performed to detect epileptiform activities. Blood will be drawn to measure levels of midazolam, fentanyl and rocuronium.

Conditions

• Cardiac Arrest With Successful Resuscitation
• Hypothermia
• Skeletal Muscle Relaxant Overdose

Interventions

DRUG

rocuronium

continuous application of rocuronium 0,25mg/kg/h (blinded), in case of shivering episode bolus sodium-chloride (blinded)

OTHER

placebo

continuous infusion of sodium-chloride (blinded), in case of shivering episode application of rocuronium 0,25mg/kg (blinded)

Sponsors & Collaborators

• Medical University of Vienna

  lead OTHER

Principal Investigators

• Heidrun Losert, MD · Medical University Vienna, Department of Emergency Medicine

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

DOUBLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2010-11-30

Primary Completion

2013-10-31

Completion

2015-04-30

Countries

• Austria

Study Locations