Page 634 - ACCCN's Critical Care Nursing

Emergency Presentations 611

Patients are observed for the development of cardiorespi- Management
ratory symptoms, including arrhythmias. Management The mainstays of patient management are pain control
focuses on specific clinical effects, ranging from oxygen and symptom management. Application of vinegar as
administration and IV fluid resuscitation through to part of first aid is important, but due to delay in the pre-
intubation/mechanical ventilation or CPR. 151,173 Antive- sentation of symptoms following a sting this may be of
nom is indicated in patients with cardiorespiratory insta- limited value. 178 Pain is severe, and opioid analgesia may
bility, cardiac arrest or severe pain unrelieved by narcotic be required; if requirements for opioids are very high,
171
analgesia. Antivenom is carried by prehospital person- fentanyl is considered. 177 There is anecdotal evidence that
nel, and administration may occur prior to ED presenta- magnesium sulfate may have a role in the management
tion. A 20,000 unit ampoule of box jellyfish antivenom of Irukandji syndrome not responsive to the above treat-
is diluted in 10 mL isotonic saline and administered IV ments, but this remains unproven. 178
over 5–10 minutes. 172 The number of ampoules used
varies with clinical status: at least one for cardiorespira- Ciguatera
tory instability; up to three for life-threatening situations
with an inadequate response; and at least six for a cardiac Ciguatera is a type of seafood poisoning caused by the
arrest. 151,173 consumption of fish, especially certain tropical reef fish,
that contain one or more naturally-occurring neurotoxins
While the application of a pressure immobilisation from the family of ciguatoxins. Ciguatera is reported as
bandage to affected limbs after vinegar application was the most common form of seafood poisoning in the
previously recommended as a first aid intervention, there world, 180 and is considered a mild non-fatal disease, with
is little current evidence supporting this in box jellyfish a world wide mortality rate ranging from 0.1–20%.
181
stings, and its application may promote additional venom Ciguatera as a tropical disease confined to latitudes
release and therefore be potentially dangerous. 171,174 Some 35°N–35°S is no longer tenable, as tropical fish are now
animal research has suggested a role for magnesium marketed throughout the world and some species, like
sulfate in management for patients not responding to tuna, mackerel and dolphin fish, also migrate consider-
antivenom. 175 able distances. In Australia, there have been numerous
outbreaks of ciguatera poisoning in Sydney and as far
south as Melbourne. 181,182
Ciguatera toxins (ciguatoxins) are among the deadliest
Practice tip poisons known, reportedly 1000 times more potent than
arsenic. 183 These heat-stable toxins originate from a
The Australian Resuscitation Council currently recommends microorganism that attaches to certain species of algae in
that a pressure immobilisation bandage is not used in the man- tropical areas around the world; these toxins become
agement of jellyfish stings. 173,176 altered after ingestion by progressively larger fish up the
food chain. 174,181

Clinical manifestations and diagnosis
Irukandji Envenomation Ciguatera poisoning typically presents as an acute gastro-

The Irukandji is a small marine jellyfish, with stinging intestinal illness, followed by a neurological illness with
tentacles capable of causing intense pain and catechol- classical symptoms of heat and cold reversal of sensation
amine release. 177 that may last for a few days after consumption of con-
taminated fish 174 (see Table 22.12).

Description and incidence A patient may become sensitive to repeated exposure to
174,181
ciguatoxins;
additional exposure to poisoning from
Irukandji syndrome is a poorly-understood marine ciguatera may be more severe than the first episode.
envenomation encountered in far northern and north- Importantly, patients exposed to ciguatera suffer recur-
western areas of Australia. 178 Death is uncommon (two rences following the consumption of seemingly innocu-
recorded deaths in Australia), attributed to cerebral ous foods (e.g. nuts, nut oils, caffeine, alcohol, or animal
haemorrhage and is associated with other comorbid protein foods), 147,181,183 with relapses months or years
conditions. 179 after the initial poisoning. 183
Diagnosis is made on a patient’s history and clinical fea-
Assessment tures: consumption of fish followed by an acute gastroin-

People stung by an Irukandji may have no symptoms testinal and neurological illness. There is no conclusive
174,181
initially, but may develop symptoms up to one hour after diagnostic test for the presence of ciguatoxins.
being stung. Irukandji syndrome produces clinical fea-
tures of severe lower back pain, muscle cramps, raised Management
blood pressure, pulse and respiratory compromise, vom- Treatment of ciguatera poisoning is supportive care and
iting and anxiety. 177 A patient with suspected Irukandji symptom management. Mannitol has been recom-
envenomation is placed in an acute area with full moni- mended, although this is only effective if used in the first
toring available. 48–72 hours of the illness. 181,184