Efficacy of Bilateral Transversus Thoracis Muscle Plane Block in Pediatric Patients Undergoing Open Cardiac Surgery [published online ahead of print, 2020 Feb 11].
What was the question?
This group was exploring whether single shot ultrasound-guided bilateral transversus thoracic muscle plane blocks in children aged 6 months to 5 years produces effective analgesia.
Regional anaesthesia in these kids is interesting to lots of people in the hope that outcomes will be better with better analgesia as part of that.
How did they go about it?
A randomised study of 0.75 mL/kg 0.2% ropivacaine in each injection vs saline injection. The blocks appear to have been performed after induction but before surgery.
Look appropriate to the question asked and the reader can develop a clear sense of the processes for the study, the general anaesthetic care and how to do the block. The primary outcome is said to be pain measured with the Modified Objective Pain Score (MOPS). There is a range of fairly standard secondary outcomes. The sample size has been calculated based on a pilot study. It looks to this clinician like a number that is statistically justified but not big enough that you’d feel confident drawing firm conclusions. I also get nervous when I see an exclusion flow chart where both sides of the diagram look absolutely identical.
The results seem much like you’d expect at first glance. A significant decrease in intraoperative and postoperative fentanyl requirement. Oddly the authors report their primary outcome measure as their 6th actual outcome, and somewhere after the things they didn’t demonstrate, and the complications that didn’t occur. They make strong assertions about time to extubation being shorter but the real world difference amounts to about 40 minutes. In a patient cohort of ASD and VSD repairs where many units would extubate immediately at the end of the procedure this is less meaningful.
The Bottom Line
This paper reports something of interest and has enough in it to suggest that regional blocks add something in line with logic. The numbers aren’t so overwhelming that you’d sit up and immediately change practice, nor do they make a reader think this block is better or worse than other options such as an erector spinae plane block. It’s enough to make you think ‘we should seriously think about what part regional analgesia is playing in our plan for these patients’, which is a useful clinical outcome.
Reviewed by Dr Andrew Weatherall