In this episode I’ll:
1. Discuss an article about using inhaled volatile agents for ICU sedation.
2. Answer the drug information question “Should IV or oral antihypertensives be used for severe hypertension in the immediate period after acute ischemic stroke?”
3. Share a resource for reversal of antithrombotics in intracranial hemorrhage.
Article
Lead author: Angela Jerath
Published in Anesthesia & Analgesia November 2016
Background
Some intensive care units use inhaled volatile agents such as isoflurane, sevoflurane, and desflurane in place of IV sedative agents.
Purported benefits of using inhaled agents are the highly titratable effects, rapid onset & offset, and lack of negative cardiovascular effects.
The authors of this systematic review and meta-analysis sought to compare the use of volatile agents versus intravenous midazolam or propofol in critical care units.
Methods
The authors reviewed randomized controlled trials comparing inhaled volatile agents (desflurane, sevoflurane, and isoflurane) for sedation to intravenous midazolam or propofol.
The primary outcome assessed the time between discontinuing sedation and tracheal extubation. Secondary outcomes included time to obey verbal commands, proportion of time spent in target sedation, nausea and vomiting, mortality, length of intensive care unit, and length of hospital stay.
Results
Eight trials with 523 patients were included in the analysis. The reduction in extubation time using volatile agents was a mean of 292 minutes with midazolam and 29 minutes with propofol. There was no significant difference in time to obey verbal commands, proportion of time spent in target sedation, adverse events, death, or length of hospital stay.
Conclusion
The authors concluded:
Volatile-based sedation demonstrates a reduction in time to extubation, with no increase in short-term adverse outcomes. Marked study heterogeneity was present, and the results show marked positive publication bias. However, a reduction in extubation time was still evident after statistical correction of publication bias. Larger clinical trials are needed to further evaluate the role of these agents as sedatives for critically ill patients.
Discussion
While this meta-analysis found statistically significant results, I am doubtful of the clinical significance.
Much like studies which examine reduction in time spent in the PACU, a reduction in time to extubation in minutes may not translate into a reduction in the ICU length of stay or other clinically meaningful parameters. Whether a patient is extubated at 8 am or 2 pm, they are most likely not leaving the ICU that day. And the day after extubation is considered the same regardless of what time of day extubation happened.
Given the author’s comments of publication bias and the doubtfulness of the clinical significance of the results, I would need to see stronger evidence of the positive effect of volatile agents before routinely using them to sedation critically ill patients.
Drug information question
Q: Should IV or oral antihypertensives be used for severe hypertension in the immediate period after acute ischemic stroke?
A: If blood pressure lowering is indicated, intravenous agents should be used. AHA/ASA guidelines recommend:
When lowering the blood pressure during acute ischemic stroke is indicated, risk would be minimized by lowering the pressure in a well-controlled manner. Controlled blood pressure lowering during acute stroke can best be achieved with intravenous antihypertensive therapies.
Resource
Earlier in 2016, the Neurocritical Care Society and Society of Critical Care Medicine published a Guideline for Reversal of Antithrombotics in Intracranial Hemorrhage. The full text of these guideline has been difficult to find online but I have fount it at this link.
These guidelines are such a great resource; I’d download them now in case this link disappears.
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.
“The authors reviewed randomized controlled trials comparing inhaled volatile agents (desflurane, sevoflurane, and isoflurane) for sedation to intravenous midazolam or propofol.”
Who was managing the trial overseeing process? What sort of data is available for that?
I did not see that type of info reported…it was a meta-analysis so each of the 8 trials is likely a little bit different from that design perspective.