Plasma epinephrine levels after epinephrine administration using different tracheal administration techniques in an adult CPR porcine model

Evidence on Adrenaline Use in Resuscitation and Its Relevance to Newborn Infants: A Non-Systematic Review

AIM

Guidelines for newborn resuscitation state that if the heart rate does not increase despite adequate ventilation and chest compressions, adrenaline administration should be considered. However, controversy exists around the safety and effectiveness of adrenaline in newborn resuscitation. The aim of this review was to summarise a selection of the current knowledge about adrenaline during resuscitation and evaluate its relevance to newborn infants.

METHODS

A search in PubMed, Embase, and Google Scholar until September 1, 2015, using search terms including adrenaline/epinephrine, cardiopulmonary resuscitation, death, severe brain injury, necrotizing enterocolitis, bronchopulmonary dysplasia, and adrenaline versus vasopressin/placebo.

RESULTS

Adult data indicate that adrenaline improves the return of spontaneous circulation (ROSC) but not survival to hospital discharge. Newborn animal studies reported that adrenaline might be needed to achieve ROSC. Intravenous administration (10-30 μg/kg) is recommended; however, if there is no intravenous access, a higher endotracheal dose (50-100 μg/kg) is needed. The safety and effectiveness of intraosseous adrenaline remain undetermined. Early and frequent dosing does not seem to be beneficial. In fact, negative hemodynamic effects have been observed, especially with doses ≥30 μg/kg intravenously. Little is known about adrenaline in birth asphyxia and in preterm infants, but observations indicate that hemodynamics and neurological outcomes may be impaired by adrenaline administration in these conditions. However, a causal relationship between adrenaline administration and outcomes cannot be established from the few available retrospective studies. Alternative vasoconstrictors have been investigated, but the evidence is scarce.

CONCLUSION

More research is needed on the benefits and risks of adrenaline in asphyxia-induced bradycardia or cardiac arrest during perinatal transition.

Feasibility study of epinephrine administration via laryngeal mask airway using a porcine model

The laryngeal mask airway (LMA) is gaining wide application as an alternative method of maintaining the airway in situations including general anaesthesia, for difficult airways and pre-hospital resuscitation. During resuscitation, drug administration via an LMA is sometimes warranted when vascular accesses cannot be established immediately. Therefore, we conducted a study on the feasibility of drug administration via the laryngeal mask airway. Twenty-four pigs were assigned into four groups according to the mode of epinephrine (adrenaline) administration: intravenous (20 microg/kg; Group 1); tracheal (50 microg/kg; Group 2), injection into the upper end of the LMA (50 microg/kg; Group 3), and via a catheter through the LMA into the trachea (50 microg/kg; Group 4). Arterial blood samples were drawn before and at 2, 4, 6, 8, 10, 12, 14, 16, and 18 min after epinephrine administration. Heart rates and arterial blood pressures were also recorded at the same time. The peak plasma epinephrine (PPE) levels were higher for Group 1 compared to the other groups, with Group 3 producing the lowest PPE levels. No significant difference was demonstrated comparing the PPE levels for Groups 2 and 4. Further, no differences were noted comparing the mean arterial blood pressure and heart rate between these two groups. In this non-arrest adult porcine model we conclude that epinephrine delivered via a catheter passing through the LMA can provide a similar effect as administration via the tracheal tube.