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Residual anaesthetic drugs in cannulae | Signal

Reference number
1140 E
Issue date27 November 2009

This Signal relates to risks to children as result of residual anaesthetic being left in cannulae after surgery.


After intravenous anaesthesia, small amounts of the agent may be left in the cannula which is then flushed into the patient when further fluid or medication is given intravenously through the same cannula. This may happen when ward staff give antibiotics or pain relief after the patient returns from theatre.


A typical incident report reads:


“I flushed the cannula with normal saline. This did not hurt her and did not cause any redness so I administered the IV heparin bolus of 0.52 ml over approx 10 seconds.  I then flushed the line with normal saline to clear it of the IV heparin. At this point, I noticed that the patient had become floppy in her mums arms…. I pulled the crash buzzer, began mouth to mouth resuscitation and shouted for help….The patient was stabilised, intubated and ventilated by crash team and taken to PICU. It was the opinion of the medical staff attending that there was still anaesthetic, likely to be a muscle relaxant, in the IV cannula extension set which I would have flushed into patient when giving the IV heparin. This information was given to patient’s mum by a consultant at the time and reiterated again to her, by me, just before the patient was taken to PICU.” 


The trigger incident was a serious event where a baby developed a bradycardia and cardiac arrest. Although successfully resuscitated, the baby suffered significant neurological damage. Local investigation suggested that muscle relaxant used during the operation remained in the ‘dead space’ of the cannula (in the baby’s foot), which was then administered inadvertently when antibiotics were given intravenously.


An examination of the wider incident database showed four additional relevant incidents in children under 12 years. All involved the sudden collapse of a child following the flushing of a peripheral line - a total of five arrests were reported. In all instances, the child had recently returned from theatre or received an anaesthetic (which may have included neuromuscular blockade).


Good practice suggests that after intravenous administration, the anaesthetist should ensure that the cannulae have been flushed through to remove any residual anaesthetic drug before children are returned to recovery wards, or wards where they may be given further fluids, antibiotics or pain relief intravenously.  


Have you had any incidents like this in your organisation?  Do you have a local policy in place? 


Let us know if you have learning to share (rrr@npsa.nhs.uk).


Relevant to: anaesthesia, surgery, paediatrics and child health



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