The effect of induced hypothermia on the duration of action of atracurium when given by infusion to critically ill children

Abstract

The aim of the study was to investigate the effect of induced hypothermia on the offset time of atracurium when given by continuous infusion to critically ill children. Over a period of 8 months, six mechanically ventilated children had a steady-state infusion of atracurium discontinued. The offset time of atracurium was assessed by train-of-four (TOF) stimulation of the ulnar nerve; recording the time taken to reach a TOF ratio of 0.9. Nine assessments were carried out. The mean offset time of atracurium was 82 min. This was significantly longer than in patients with temperatures within the normal physiological range. When considering all assessments, performed both in hypothermic and normothermic patients, there is a strong correlation between rectal temperature and the offset time of atracurium. Prolonged moderate hypothermia has a very significant effect on the offset time of atracurium when given by infusion to critically ill children.

Sedation and neuromuscular blockade in paediatric intensive care: a review of current practice in the UK

“…In an effort to prevent shivering, the majority of such children are given neuromuscular blocking agents. Almost all units commence neuromuscular blockade using standard dosing schedules, despite evidence of a significant reduction in the requirements for such agents in the presence of induced hypothermia (12). Children managed in this way will receive excessive doses of neuromuscular blocking agents and are at increased risk of developing complications, including prolonged neuromuscular weakness following their discontinuation.…”

The effects of age, isoflurane and sevoflurane on atracurium in lambs

“…1992; Leslie et al. 1995; Playfor et al. 2000b) although considerably greater temperature changes (2–11 °C) were involved.…”

Consensus guidelines for sustained neuromuscular blockade in critically ill children

“…Although some organ uptake has been demonstrated and 10% of the drug is excreted in the urine, the effects of atracurium have not been shown to be prolonged in renal or hepatic failure. There is a strong correlation between rectal temperature and the offset time of atracurium; prolonged moderate hypothermia has a very significant effect on the offset time of atracurium when given by infusion to critically ill children (15). Clearance of atracurium also tends to be faster in children than in adults.…”