When Cooling a Patient After Cardiac Arrest, Does Use of a Neuromuscular Blocking Agent Make Your Job Easier?

NCT ID: NCT02033733

Last Updated: 2014-01-13

Basic Information

• Recruitment Status: UNKNOWN
• Total Enrollment: 400 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2014-01-31
• Study Completion Date: 2015-02-28

Brief Summary

After successful resuscitation from cardiac arrest, cooling the whole body is a well established treatment that improves the chances of the brain recovering. This however, has to be done within a certain time-frame from the arrest. The purpose of this study is to explore the best way of dosing the muscle relaxing medications that are given during the cooling process.

Hypothesis: In the context of our institutional therapeutic hypothermia protocol, cisatracurium infusions lead to faster drops in core temperature when compared to cisatracurium prn boluses alone.

Detailed Description

STUDY RATIONALE:

A large proportion of comatose survivors of cardiac arrest presenting to our intensive care units at London Health Sciences Centre (LHSC) undergo therapeutic hypothermia. Current evidence suggests that timely achievement of target temperatures is desirable to improve outcomes. At LHSC, this intervention is protocolized with a defined set of preprinted orders that includes a dosing regimen for neuromuscular blocking agents (NMBA's). Our preprinted protocol has been in place since January of 2004. Cisatracurium infusions were part of the therapeutic hypothermia protocol until October 2011. Since that time, our protocol has changed to cisatracurium prn boluses for any observed shivering. In this study we will examine if there has been any change in the times to achieving target temperatures with the implementation of this change. It is important to note that no other change in our protocol has taken place since it was first implemented, making our before and after comparison valid and fair.

Our hypothesis is that NMBA infusions lead to a faster drop in core temperatures when compared to NMBA prn boluses. If this were to stand true, we would expect cisatracurium IV infusions to result in faster reductions in core temperature when compared with cisatracurium prn boluses in the context of our therapeutic hypothermia protocol. Hypothermia has been known to cause a subclinical increase in muscle tone. This previously reported phenomenon has been named "microshivering". When attempting to reduce core temperatures, microshivering is likely a natural body response to try to restore body temperature back to normal. We therefore hypothesize that NMBA infusions are likely more effective at abolishing microshivering, which would be a desirable effect when trying to induce therapeutic hypothermia.

Although current American Heart Association (AHA) guidelines suggest considering the administration of NMBA's to facilitate induced hypothermia and control shivering. Their recommendation is to minimize the duration of NMBA use or if possible, avoid them altogether. After the publication of these guidelines our institutional protocol changed to prn boluses instead of the previous infusion orders. We therefore believe it is important to examine the effects of this change on our cooling protocol and potentially add to the growing body of knowledge in this field.

Conditions

Postcardiac Arrest Therapeutic Hypothermia

Study Design

• Observational Model Type: COHORT
• Study Time Perspective: RETROSPECTIVE

Study Groups

Adequate cooling time

Patients that reached target temperature within 4 hours of initiation of the hypothermia protocol will be in the "adequate cooling time" group.

Cisatracurium infusion

Intervention Type: DRUG

This group will include postcardiac arrest patients that have received a cisatracurium infusion as part of their therapeutic hypothermia protocol. It will only include patients that had their infusion started within 2 hours from protocol initiation. Patients that received an infusion as a rescue measure (beyond the first 2 hours) or did not receive and infusion at all will not be included in this group.

Most patients admitted to our ICU postcardiac arrest prior to October 2011, will likely belong to this group (the cisatracurium infusion group).

Cisatracurium prn bolus

Intervention Type: DRUG

Patients that have not received a cisatracurium infusion within the first 2 hours from protocol initiation will be in this group. These are likely to be patients admitted to our ICU after October 2011 (when the protocol change happened).

Inadequate cooling time

Patients that did not reach target temperature within 4 hours of initiation of the hypothermia protocol will be in the "inadequate cooling time" group.

Cisatracurium infusion

Intervention Type: DRUG

This group will include postcardiac arrest patients that have received a cisatracurium infusion as part of their therapeutic hypothermia protocol. It will only include patients that had their infusion started within 2 hours from protocol initiation. Patients that received an infusion as a rescue measure (beyond the first 2 hours) or did not receive and infusion at all will not be included in this group.

Most patients admitted to our ICU postcardiac arrest prior to October 2011, will likely belong to this group (the cisatracurium infusion group).

Cisatracurium prn bolus

Intervention Type: DRUG

Patients that have not received a cisatracurium infusion within the first 2 hours from protocol initiation will be in this group. These are likely to be patients admitted to our ICU after October 2011 (when the protocol change happened).

Interventions

Cisatracurium infusion

This group will include postcardiac arrest patients that have received a cisatracurium infusion as part of their therapeutic hypothermia protocol. It will only include patients that had their infusion started within 2 hours from protocol initiation. Patients that received an infusion as a rescue measure (beyond the first 2 hours) or did not receive and infusion at all will not be included in this group.

Most patients admitted to our ICU postcardiac arrest prior to October 2011, will likely belong to this group (the cisatracurium infusion group).

Intervention Type: DRUG

Cisatracurium prn bolus

Patients that have not received a cisatracurium infusion within the first 2 hours from protocol initiation will be in this group. These are likely to be patients admitted to our ICU after October 2011 (when the protocol change happened).

Intervention Type: DRUG

Other Intervention Names

Neuromuscular blocking agent infusion; NMBA infusion; Continuous NMBA infusion; Continuous cisatracurium infusion; Cisatracurium by continuous infusion; neuromuscular blocking agent prn bolus; NMBA prn bolus; cisatracurium intermittent bolus; intermittent bolus administration of cisatracurium

Eligibility Criteria

Inclusion Criteria

• Admission to adult ICU (age ≥18 years) at London Health Sciences Centre
• Primary reason for ICU admission: postcardiac arrest
• Both in-hospital and out-of-hospital cardiac arrest will be included
• ICU admission between Jan 2008 and Dec 2012.

Exclusion Criteria

• ICU admissions primarily for reasons other than cardiac arrest.

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 90 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

University of Western Ontario, Canada

OTHER

Sponsor Role: collaborator

London Health Sciences Centre Research Institute OR Lawson Research Institute of St. Joseph's

OTHER

Sponsor Role: lead

Responsible Party

Eyad AlThenayan

Dr. Eyad AlThenayan

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Eyad Althenayan, MD

Role: PRINCIPAL_INVESTIGATOR

Western University, Canada

Philip Jones, MD, FRCPC

Role: STUDY_DIRECTOR

Western University, Canada

Bryan Young, MD, FRCPC

Role: STUDY_CHAIR

Western University, Canada

Ahmed F Hegazy, MD, FRCPC

Role: STUDY_DIRECTOR

Western University, Canada

Ana Igric, MD, FRCSC

Role: STUDY_DIRECTOR

Western University, Canada

Carolyn Benson, MD

Role: STUDY_DIRECTOR

Western University, Canada

Locations

University Hospital, London Health Sciences Centre, University of Western Ontario

London, Ontario, Canada

Victoria Hospital, London Health Sciences Centre, University of Western Ontario

London, Ontario, Canada

Countries

Canada

Central Contacts

Ahmed F Hegazy, MD, FRCPC

Role: CONTACT

ahmed.hegazy@londonhospitals.ca

1(519) 860-4917

Eyad AlThenayan, MD

Role: CONTACT

Eyad.Althenayan@lhsc.on.ca

Facility Contacts

Ahmed F Hegazy, MD, FRCPC

Role: primary

ahmed.hegazy@londonhospitals.ca

1(519) 860-4917

Eyad Althenayan, MD

Role: backup

eyad.althenayan@lhsc.on.ca

1 (519) 685-8500 ext. 19119

Ahmed F Hegazy, MD, FRCPC

Role: primary

ahmed.hegazy@londonhospitals.ca

1(519) 860-4917

Eyad Althenayan, MD

Role: backup

eyad.althenayan@lhsc.on.ca

1 (519) 685-8500 ext. 19119

References

Sendelbach S, Hearst MO, Johnson PJ, Unger BT, Mooney MR. Effects of variation in temperature management on cerebral performance category scores in patients who received therapeutic hypothermia post cardiac arrest. Resuscitation. 2012 Jul;83(7):829-34. doi: 10.1016/j.resuscitation.2011.12.026. Epub 2012 Jan 8.

Reference Type: BACKGROUND

PMID: 22230942 (View on PubMed)

Werlhof V, Sessler DI. Pancuronium does not decrease oxygen consumption during hypothermic or normothermic cardiopulmonary bypass. Anesth Analg. 1995 Sep;81(3):465-8. doi: 10.1097/00000539-199509000-00006.

Reference Type: BACKGROUND

PMID: 7653805 (View on PubMed)

Peberdy MA, Callaway CW, Neumar RW, Geocadin RG, Zimmerman JL, Donnino M, Gabrielli A, Silvers SM, Zaritsky AL, Merchant R, Vanden Hoek TL, Kronick SL; American Heart Association. Part 9: post-cardiac arrest care: 2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care. Circulation. 2010 Nov 2;122(18 Suppl 3):S768-86. doi: 10.1161/CIRCULATIONAHA.110.971002.

Reference Type: BACKGROUND

PMID: 20956225 (View on PubMed)

Other Identifiers

5511

Identifier Type: -

Identifier Source: org_study_id