Volume 180 - Issue 9

Sublingual glyceryl trinitrate as prehospital treatment for hypertension in Irukandji syndrome

Author:  Peter J Fenner

Med J Aust 2004; 180 (9): 482-484. || doi: 10.5694/j.1326-5377.2004.tb06035.x
Published online: 3 May 2004

In reply: We did not provide evidence of any effect on pulmonary oedema, myocardial injury or any effect in stopping pain, as that was not our intention. Also, even intravenous nitrates that have been used for many years in hospital are ineffective in reducing the muscle-cramping pains of Irukandji envenomation, and, although they reduce hypertension and ischaemic myocardial pain, there is no correlation or evidence that they prevent pulmonary oedema or myocardial injury.

The assumption that the Queensland Ambulance Service (QAS) introduced this treatment after our trial is incorrect. The QAS Medical Director will confirm that it was introduced independently of our trial and actually before we treated our first case.

While pain causes hypertension, in our Patient 1 effective analgesia had been attained without any effect on his hypertension. Also, many patients with Irukandji syndrome have pain without hypertension, while others have severe hypertension even with effective pain control.1 Further evidence that the venom from Carukia barnesi is a sodium channel modulator has been submitted for publication (Ken Winkel, Director, Australian Venom Research Unit, Melbourne, personal communication).

Carukia barnesi has now been caught in the Mackay region, 400 kilometres south of Townsville (identified by me, and confirmed by L A Gershwin, PhD student in cubozoan taxonomy, James Cook University, 2003, personal communication). A number of other species can cause the Irukandji syndrome, but the jellyfish causing the sting is rarely caught, so cause and effect are hard to establish at present.

Our aim was to present early evidence that sublingual nitrates may be effective in reducing the hypertension that occurs in some cases of Irukandji syndrome; our suggestion was that they be further trialled.2 It seems worthwhile to do so, especially as sublingual nitrates have also been shown to be effective in dysreflexia from spinal injury,3 where hypertension also occurs from the massive release of similar catecholamines.

At least two deaths have occurred after Irukandji envenomation, both as a result of cerebrovascular accidents from severe hypertension.4 When treating a patient with severe hypertension from Irukandji envenomation in a prehospital situation, it is reasonable to try to reduce the hypertension. Doing so might reduce the risk of a cerebrovascular accident and possible death, and so further trials of this prehospital treatment must take place. Other prehospital treatments must also be trialled, especially those for pain. Early promising leads need to be published early for all to evaluate. The Irukandji syndrome is a dreadful experience for the victim; all possible prehospital relief measures must be tried and evaluated.


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