A double blind randomized controlled trial - Effect of intravenous dexamethasone on the onset time and recovery profiles of atracurium in children

Background and rationale :

Dexamethasone is commonly used in the perioperative period for the prevention of postoperative nausea and vomiting (PONV), and for reducing the severity of postoperative pain and requirement of opioids. The frequent use of dexamethasone in the perioperative period albeit as a single dose as brought out the question of possible drug interactions with other anaesthetic agents.

It has been shown previously that chronic steroid intake can reduce the duration of neuromuscular block. Moreover, methylprednisolone given intravenously pre or intraoperatively can reduce the duration of action of neuromuscular blockers. Few trials on phrenic nerve-diaphragm preparations in rats have also shown that dexamethasone can shorten the duration of action of neuromuscular blockers. More recently Young so et al showed that intravenous dexamethasone can also have the same effect on neuromuscular blockers. In both these trails clinically relevant change in the duration of action of neuromuscular blockers have only been seen when the dose was administered atleast 2 to 3 hours prior to induction. However, in clinical practice dexamethasone is commonly given only at induction. This could take clinical relevance if the duration of surgery extends beyond 2 or 3 hours.

Moreover, both these trails were done only on adult population. Till date there have been no studies carried out in children to demonstrate the effect of intravenous dexamethasone on neuromuscular blocking agents. Hence it would be naïve to directly extrapolate the findings in adult population to children owing to the different physiological profile in them.

Thus, the present study aimed to demonstrate the effect of dexamethasone on the duration of action of atracurium in children undergoing elective surgery under general anesthesia. The Primary objective was to assess the impact on onset time and incidence of incomplete neuromuscular block. The secondary outcomes were clinical duration, recovery index, recovery time, and total recovery period.

Results: The onset time and recovery index time were lower (1.96± 0.39, 8.04± 2.14 respectively) with dexamethasone in comparison to saline (2.01± 0.51, 8.9± 3.4 respectively) but not statistically significant. The clinical duration, recovery time, and total Recovery period were similar.No instances of incomplete neuromuscular block.

Conclusion: Application of a single bolus dose (0.15 mg/kg) of dexamethasone during induction does not attenuate atracurium-induced neuromuscular blockade in children.