Nursing Process for Post-Operative IV Ketamine Infusion
Eva M. Caruso, APRN, M.S.N., Assistant Professor of Nursing, Mayo Clinic College of Medicine
IV infusion of ketamine was historically exclusive to Intensive Care Units (ICUs) at Mayo Clinic AZ. Anesthesia and Nursing leadership evaluated whether it was within the scope of practice for RNs practicing in general post-operative care areas to administer low dose IV ketamine. They benchmarked with similar academic medical centers and found that low dose IV ketamine was administered by general care RNs to post-operative patients and patients with chronic pain in areas other than ICUs, including medical-surgical units, step-down units, and general care units.
Change in Scope of Practice
Post-operative IV ketamine infusion was identified as a practice change for Nursing. Support was sought from the Mayo Clinic AZ Department of Nursing, the Chief Nursing Officer, the Hospital Practice Subcommittee and the Nursing Practice Subcommittee, all of which endorsed seeking approval from the Arizona State Board of Nursing.
A request was made to the Arizona State Board of Nursing, Scope of Practice Committee. The presentation summarized literature on the efficacy of low dose IV ketamine, benchmarking information, drug information, potential adverse effects, and monitoring requirements. The committee requested an Advisory Opinion (AO) to support administration of low dose IV ketamine by RNs in general post-operative care areas. The AO included ketamine dosing parameters, monitoring requirements, and educational requirements for RN staff.
The AO was approved by the Arizona State Board of Nursing, Scope of Practice Committee (link below).
Intra- and Post-Operative Ketamine Use
Andrew W. Gorlin, Assistant Professor of Anesthesiology, Mayo Clinic College of Medicine
Ketamine is an NMDA antagonist which, when administered intravenously at sub-anesthetic doses (≤0.3mg/kg bolus or ≤0.3mg/kg/hr infusion), provides analgesia and has a significant opioid sparing effect in the perioperative setting. There is also evidence that ketamine is useful in treating acute pain in patients who are opioid tolerant. Sub-anesthetic infusions of ketamine can be safely administered on standard medical-surgical units.
Perioperative indications for ketamine infusion:
- Very painful procedures
- Intractable opioid-resistant pain
- Highly opioid tolerant patients
- Clinical need to minimize opioids
- High risk for persistent post-surgical pain (eg amputation, thoracotomy, etc)
- Non-opioid analgesic which reduces perioperative opioid consumption
- At sub-anesthetic doses has minimal hemodynamic effects
- At sub-anesthetic doses has no effect on respiratory drive or airway patency
- Low-moderate incidence (7-16%) of psychomimetic effects such as hallucinations and dysphoria
- Low incidence of diplopia (4-9%)
- Especially when administered in combination with other CNS depressants may contribute to sedation
- History of psychosis
- Unstable cardiovascular disease
- Liver or renal failure
How to administer ketamine:
Intraoperatively: Anesthesia team can give single bolus with induction and/or serial boluses (every 30-60 minutes) in the operating room (initial 0.3mg/kg and then subsequent 0.1-0.3mg/kg boluses every 30-60 minutes)
- Post-operative infusion requires coordination with the OR, PACU, med-surg unit
- Ketamine is a controlled substance and should be prepared in a secure storage system (such as a PCA cartridge) by pharmacy and administered by an infusion pump
- Dose should be ≤0.3mg/kg/hr based on Ideal Body Weight; a good starting point for most patients is 10mg/hr
- A separate IV is preferable though it can be safely “piggy-backed” onto another line as long as it is on a distal port (ie, close to the patient)
- Side effects can be managed on a case by case basis but typically hallucinations and other complains will stop within an hour of stopping the infusion
- Use of benzodiazepines to reduce psychomimetic effects is controversial and may cause more problems with sedation and delirium
- AZ Board of Nursing required EKG monitoring for the duration of infusion, based on an “increase in scope” of nursing practice.