Low-Dose Ketamine Versus Opioids For Analgesia: Efficacy and Safety

Authors

Jonathan D. Cuthriell, University of LynchburgFollow

Specialty

Emergency Medicine

Advisor

Dr. Nancy Reid

Abstract

Every year approximately 140 million people will seek care in an Emergency Department (ED) in the US alone. Patients seek care for a variety of medical reasons, but the most common chief complaint in the Emergency Department is pain.Many of these patients will need definitive pain management to manage their pain. Traditionally, patients have received parenteral opioid pain medication such as Morphine, Fentanyl, or Dilaudid. However, these medications have a potentially serious side effect profile, including potent vasodilation, respiratory depression, myoclonus, nausea and vomiting, sedation, as well as addictive properties. That side effect profile may potentially cause serious deleterious effects for patients in both the immediate care setting of the Emergency Department as well as the long-term consequences once discharged. In fact, the Joint Commission released a sentinel event alert in 2012, which stated that the opioid medications had the highest incidence of adverse effects of all medication classes. The questions providers must ask, is there another medication that can manage patients’ pain with fewer side effects? One such medication might be sub-dissociative dosing/low-dose (LDK) ketamine.

After a review of the literature, the results show that patients may safely receive Ketamine in any of the medication administration forms, IV, IM, or Intranasally. Furthermore, LDK protocols may either set a standardized dose for adults of 10-15 mg or use a weight-based formula. The most common dosing for weight-based dosing was 0.3 mg/kg, but providers may increase dosing to 0.5 mg/kg. All result with good analgesia and no reported life-threatening outcomes. LDK also appears to have a short analgesic effect. Most studies show maximum effect within 15-30 minutes of administration. Based on the drug literature, as well as study results, it appears that Ketamine should be able to be repeated within 30 min to 1 hour of administration with no deleterious effect. LDK would be recommended for most acute pain complaints in the ED as there was no significant difference in findings across the different etiologies of pain complaints that were treated in the cases. One note of caution with cardiac chest pain should be noted. Ketamine has no vasodilative properties. As morphine does exhibit these properties, it is not recommended that LDK replace morphine in “Morphine, Oxygen, Nitro, Aspirin” type chest pain protocols. Pending further human studies, caution would be advised on the use of LDK for the use in the pregnant and breastfeeding female.

Recommended Citation

Cuthriell JD. Low-Dose Ketamine Versus Opioids For Analgesia: Efficacy and Safety. University of Lynchburg DMSc Doctoral Project Assignment Repository. 2019; 1(3).