In this episode I’ll:
1. Discuss an article about preoperative oral versus intraoperative i.v. acetaminophen.
2. Answer the drug information question “Should vasopressin be started at the same time as norepinephrine in septic shock?”
3. Share a resource on what a pharmacist should know about mechanical ventilation.
Lead author: Skip R. Hickman
Published in American Journal of Health-System Pharmacy March 2018
IV acetaminophen has been available in the US since 2010. Different perioperative analgesic protocols involving oral or intravenous acetaminophen are used for patients undergoing orthopedic surgery. The authors of this study sought to compare pain control outcomes with preoperative oral versus intraoperative i.v. acetaminophen use in adults undergoing total hip or knee arthroplasty.
The study was a single-center, randomized, placebo-controlled, equivalence trial. Patients were assigned 1:1 to receive 1000 mg acetaminophen before surgery, with an i.v. placebo infusion during surgery, or placebo capsules followed by an i.v. infusion of acetaminophen 1,000 mg. Patients were followed after postanesthesia care unit (PACU) admission up to 24 hours postoperatively.
Results were analyzed for 486 patients. There were no significant differences in preoperative and intraoperative use of pain medication between the oral and i.v. acetaminophen groups. Postoperative opioid use in morphine milligram equivalents were equivalent in the oral and i.v. groups. There were also no significant between-group differences in mean pain scores over 24 hours reported.
The authors concluded:
In patients undergoing hip or knee arthroplasty, oral acetaminophen given preoperatively was equivalent to i.v. acetaminophen administered in the operating suite in controlling pain in the immediate postoperative period. I.V. acetaminophen was not superior to oral acetaminophen in reducing postoperative nausea and vomiting, time to ambulation, time to first dose of as-needed pain medication, length of PACU stay, or total length of hospital stay.
To my knowledge, no study has ever demonstrated a clinically meaningful benefit to IV acetaminophen over an active comparator. When the price of IV acetaminophen tripled a few years ago, it was taken off formulary at many institutions, mine included. Very occasionally I miss having the medication available for that rare npo patient that cannot tolerate other analgesic options. But other than that rare niche use, I see no role for the use of IV acetaminophen in hospital patients, and this study, as well as some other recent articles, support that contention.
Drug information question
Q: Should vasopressin be started at the same time as norepinephrine in septic shock?
A recent randomized trial concluded that:
Patients treated with early, concomitant vasopressin and norepinephrine achieved and maintained MAP of 65 mm Hg faster than those receiving initial norepinephrine monotherapy, suggesting that overcoming vasopressin deficiency sooner may reduce the time patients spend in the early phase of septic shock.
In this trial, vasopressin was initiated within 4 hours of norepinephrine and the time to achieve and maintain goal MAP was 5.7 hours vs 7.6 hours with norepinephrine alone. Mortality was not different between groups so it remains to be seen if starting vasopressin at the same time as norepinephrine results in any clinically meaningful outcomes.
The resource for this episode is my free, 2-page pdf on what a pharmacist should know about mechanical ventilation. This pdf explains the goals and indications for ventilation and airway management, types of mechanical ventilation, mechanical ventilator modes, and the role of the pharmacist in facilitating pharmaceutical care for patients receiving mechanical ventilation. To access this pdf sign up for my free download area at pharmacyjoe.com/free. It’s download #6.
If you like this post, check out my book – A Pharmacist’s Guide to Inpatient Medical Emergencies: How to respond to code blue, rapid response calls, and other medical emergencies.