Impact of Low-Dose Ketamine on the Usage of Continuous Opioid Infusion for the Treatment of Pain in Adult Mechanically Ventilated Patients in Surgical Intensive Care Units

Abstract

Low-dose continuous infusion ketamine in mechanically ventilated adult patients was associated with a significant increase in the rate of opioid dose reduction without adverse effects on hemodynamic stability.

Consensus Guidelines on the Use of Intravenous Ketamine Infusions for Acute Pain Management From the American Society of Regional Anesthesia and Pain Medicine, the American Academy of Pain Medicine, and the American Society of Anesthesiologists

“…Reductions in opioid consumption have been demonstrated in mechanically ventilated, surgical intensive care patients on opioid infusions when ketamine was initiated at a low-dose continuous infusion rate of 0.06 to 0.30 mg/kg per hour. 32 However, in a recent small study of 48 pediatric patients undergoing scoliosis spine surgery, a subanesthetic ketamine dose of 0.5 mg/kg followed by an infusion at 0.12 mg/kg per hour for 72 hours yielded no significant differences in opioid consumption or pain scores compared with placebo. 33 In a longitudinal cohort study performed in 230 children, adolescents, and young adults, patients with acute (78%) and chronic (22%) pain were given different doses of ketamine infusions depending on whether they were opioid tolerant.…”

Adjunct low-dose ketamine infusion vs standard of care in mechanically ventilated critically ill patients at a Tertiary Saudi Hospital (ATTAINMENT Trial): study protocol for a randomized, prospective, pilot, feasibility trial

“…The sample size calculation associated with the specified (required) number of patients to be recruited is based on the study by Buchheit et al [9]. In their study, the median time from initiation of ketamine to extubation was 1.44 days (IQR 0.58-2.66).…”

“…The primary outcome is median duration of MV: the number of calendar days from intubation date to extubation date, until ICU discharge, death, or 28 days post-randomization, whichever comes first. This outcome was chosen as a patient-centered outcome and based on the mechanistic plausibility data that showed ketamine possibly has a bronchodilatory effect and maintains respiratory drive and airway reflexes [9,12,13]. Because duration of MV is highly influenced by mortality, the median ventilator-free days to day 28 post-randomization will be calculated as a co-primary outcome [23].…”

“…The incidence of side effects (i.e., nausea, delirium, hallucination, hypoventilation, pruritus, and sedation) did not differ between the ketamine and opioidalone groups. Based on this generally positive ICU RCT, the 2018 PADIS panel made a conditional recommendation for the use of low-dose ketamine as an adjunct to opioids to optimize acute post-operative pain management in critically ill adults (refer to Supplementary Table 1: Previous ketamine trials in the ICU setting) [2][3][4][5][6][7][8][9][10][11].…”

“…However, most patients in the ICU are sedated with a combination of drugs. Moreover, most trials had a limited focus on patientcentered outcomes, such as duration of MV or ICU LOS, as the primary outcome favoring surrogate outcomes, such as sedation scores and changes in analgesics and sedatives [2][3][4][5][6][7][8][9][10][11]. To help further delineate ketamine's role as a maintenance analgo-sedation agent in the ICU, further RCTs need to be conducted to compare the effects of ketamine to those of other analgesics and sedatives on reducing the duration of MV, ICU LOS, and delirium occurrence.…”