Intravenous drug administration during out-of-hospital cardiac arrest

Olasveengen, JAMA. 2009, 302(20):2222-2229

Clinical Question

• In patients with an out-of-hospital cardiac arrest does removing the use of intravenous medications improve survival?

Design

• Randomised controlled trial
• Use of sealed envelopes to ensure allocation concealment
• Non-blinded

Setting

• Pre-hospital, Oslo, Norway
• 01.05.2003. – 28.08.2008.

Population

• Inclusion: adult patients with out-of-hospital (OOH) cardiac arrests
• Exclusion: traumatic cardiac arrest; arrest secondary to asthma/anaphylaxis; arrest witnessed by ambulance staff
• 851 patients included out of 1183 patients for whom resuscitation attempted

Intervention

• Use of intravenous drug administration together with Advanced Cardiac Life Support (ACLS)
  • according to standard guidelines (administered adrenaline, atropine, amiodarone as per guidelines at that time)

Control

• Did not attempt intravenous drug administration with ACLS

Outcome

• Primary outcome: survival to hospital discharge – No significant difference
  • Comparing IV with ‘No IV group’: 10.5% vs. 9.2% (Odds ratio 1.16, 95% C.I. 0.74-1.82, P=0.61)
• Secondary outcomes:
  • Return Of Spontaneous Circulation (ROSC) – overall significant improvement in IV group
    • 40% vs. 25% (OR 1.99, 95% C.I. 1.48-2.67, P<0.001)
  • ROSC in patients presenting with VF/VT – no significant difference
    • 59% vs. 53%, P=0.35
  • ROSC in patients presenting with PEA/asytole – significant improvement in IV group
    • 29% vs. 11%, P<0.001
  • Survival with good neurological outcome – no significant difference
    • 9.8% vs. 8.1%  (OR 1.24, 95% C.I. 0.77-1.98, P=0.45)

Authors’ Conclusions

• Patients in OOH cardiac arrest had increased rates of ROSC, but no statistically significant improvement in survival to discharge.

Strengths

• Randomised
• Quality of chest compressions assessed
• All patients treated with post-resuscitation protocols including therapeutic hypothermia
• Intention to treat analysis

Weaknesses

• May have been under-powered, as power calculation determined on basis of doubling survival rate. For the observed differences to be statistically significant a sample size of 14,000 patients would be needed
• In IV group only 79% received adrenaline