Introduction
Survival after CPR with epinephrine therapy is disappointing. Increasing evidence from laboratory and clinical studies suggests that vasopressin may be a promising alternative vasopressor during cardiac arrest and resuscitation.
Methods and patients
We performed our study in the prehospital setting in Prehospital Unit Maribor after approval of The Ethical review board of The Ministry of Health. Patients were eligible if they had a cardiac arrest and required epinephrine according to ERC ACLS protocols for refractory VF. We gave patients one intravenous dose of vasopressin (40 U) after 3 × 1 mg epineprine. If there was no return of pulse after vasopressin, patients as before received epinephrine 1 mg every 3 min during CPR. We excluded patients who were younger than 18 years, had a documented terminal illness, had a traumatic cardiac arrest, were in severe hypothermia (<30°C), had PEA or asystole as initial rhythm or received drugs via endotracheal tube.
Results
See Table 1. During the trial (from November 2000 to October 2001) we successfully followed up 20 patients and compared them with 20 patients with equal characteristics from retrospective study. Our preliminary study shows a significantly better results in patients treated with vasopressin for ROSC and 24 hour survival, additional doses of epinephrine were less needed (P < 0.05). Respectively more patients treated with vasopressin were discharged from hospital (P = 0.18).
Table 1.
Baseline and treatment characteristic and survival outcomes
| Epinephrine only | Vasopressine | P value | |
|---|---|---|---|
| Sex (M/F) | 9/11 | 9/11 | 1* |
| Age | 60.8 ± 11.2 | 59.6 ± 10.9 | 0.90† |
| Time collapse to CPR | 7.2 | 8.1 | 0.81† |
| Additional epinephrine (number of patients) | 20 | 10 | < 0.05† |
| Any ROSC (Y/N) | 9/11 (45%) | 16/4 (80%) | < 0.05* |
| Hospitalization (Y/N) | 8/12 (40%) | 13/7 (65%) | 0.26* |
| 24 hour survival (Y/N) | 5/15 (25%) | 12/8 (60%) | < 0.05* |
| Discharge of hospital (Y/N) | 3/17 | 7/13 | 0.18* |
* Chi square test; † Student t-test.
Conclusion
These results suggest possible indication for vasopressin in refractory out-of-hospital VF, after initial application of epinephrine. Based upon our preliminary study larger and prolonger studies of vasopressin in treatment of out-of-hospital VF are needed.