There are multiple routes of medication delivery for the critically ill patient. Commonly, these include the intravenous (IV) and intraosseous (IO) routes as well as the endotracheal tube, intramuscular, or clysis.
But what can you do when the these routes are not feasible or desirable in a crashing patient?
Sublingual (SL) injection may provide an important route for drug administration.
This may be especially helpful for infants in cardiopulmonary arrest. There is a high preshospital failure rate for IV access and ETT placement in this group, and the SL route originates from EMS providers.
Rothrock et al. describe a case where paramedics were called to the scene of a witnessed cardiac arrest of a 7-month old child whose parents had started immediate CPR. After multiple failed attempts at endotracheal intubation and IV access, the paramedics injected 1.5 mg epinephrine (0.2 mg/kg) followed by 0.15 mg atropine (0.02 mg/kg) sublingually. Within 30 to 60 seconds, the child achieved return of spontaneous circulation (ROSC) with a palpable pulse and a heart rate of 180.
There is no standard technique for SL injection, however, the rich vascular plexus in the sublingual region allows for rapid uptake of injected medications. Classically, SL injection is performed 1-2 cm from the midline of the frenulum into the sublingual vascular plexus.
Animal and human studies have shown that higher doses of medications must be administered SL in order to reach identical serum concentrations of peripherally administered medications. More research is needed on dosing regimens via the SL route.
Regardless, EMS providers often utilize SL injections of 0.3-0.5mL of 1:1000 epinephrine for anaphylaxis patients where IV/IO access is unavailable. Naloxone, flumazenil and ketamine have also been administered effectively via the SL route.
Next time you have a patient in extremis without vascular access, remember sublingual injection as a route for administration of initial resuscitative medications.
-- Megan Stultz, MD & Eric Beck, DO EMT-P
Losek JD, Hennes H, Glaser P, et al: Prehospital care of the pulseless, nonbreathing pediatric patient. Am J Emerg Med 1987; 5:370-374.
McIntyre KM (ed): Standards and guidelines for cardiopulmonary resuscitation (CPR) and emergency cardiac care (ECC). JAMA 1980; 244:453-509.
Ordog GJ, Wasserberger J, Jones J, et al: Efficacy of absorption of sublingual and intravenous Cardio-Green. Ann Emerg Med 1984; 13:426-428.
Rothrock SG, Green SM, Schafermeyer RW, Colucciello SA. "Successful resuscitation from cardiac arrest using sublingual injection for medication delivery." Ann Emerg Med 1993; 22:751-753.