Australian Doctor 16th February 2024 AD 16th Feb issue | Page 18

18 HOW TO TREAT : MARINE STINGS AND POISONING

18 HOW TO TREAT : MARINE STINGS AND POISONING

16 FEBRUARY 2024 ausdoc . com . au tentacles have made contact with the skin . The pain lasts for minutes to hours , depending on the degree and duration of contact . A linear erythematous mark develops at the sting site ( see figure 2 ) and remains for one or two days . More widespread redness or flushing may also occur . Systemic effects are rare but can include nausea , vomiting , abdominal pain and myalgia . Delayed reactions are uncommon , but a localised bullous reaction may occur days after the sting . Scarring is rare .
TREATMENT First-aid includes removing the tentacles — either by washing them off with sea water ( not fresh water ) or picking them off carefully . Hot water immersion ( 45 ° C ) for 20 minutes is the recommended treatment for local pain . A randomised controlled trial showed that hot water was more effective than ice packs for bluebottle stings . 2
It is important for someone else to test the temperature of the water first or for the patient to test it with the unaffected limb . If immersion in hot water is not possible , then alternatives include a hot shower or a constant flow of hot water onto the sting site . Do not apply vinegar to the sting as this may increase the pain .
Medical treatment is rarely required and , where indicated , includes symptomatic relief with analgesia and local dressing for more severe skin reactions .
Figure 1 . Bluebottle .
Major box jellyfish
The major box jellyfish is the most
dangerous jellyfish in Australia and
is often referred to as the world ’ s
most venomous animal . In the past
30 years , there have been more than
70 deaths from C . fleckeri stings , and
almost all of these have been children . 3 These jellyfish are distributed in the far north of Australia , and
many stings occur in remote areas
with little access to medical care . 3
Most stings are minor , but severe
and life-threatening stings occur
with a large area of skin contact with
the tentacles . C . fleckeri have multiple
tentacles attached to each of the
four corners of their box shape . This
makes it possible for several metres of
tentacle contact to occur , resulting in
severe envenoming . Just over 1m of
tentacle contact has resulted in death
in a child .
CLINICAL EFFECTS
Most C . fleckeri stings are similar to
those from other jellyfish tentacle stings , with intense local pain and linear raised erythematous reactions ( see table 1 ). However , there are often
Figure 2 . Bluebottle sting around two hours after the sting .
multiple sting marks that characteristically
appear as red or dark purple whip-like lesions ( see figure 3A ).
Box 1 . Major clinical syndromes with jellyfish stings
TREATMENT Patients with severe chironex enven-
The major issue in less severe envenoming is local pain , and ice
The severity and duration of the pain is generally much worse than with other jellyfish stings , such as a bluebottle . In addition , local necrosis can occur with C . fleckeri stings , but this rarely causes permanent injury or scarring . In more than half of cases ,
• Linear tentacle-like stings : — Stings result from contact with the tentacles . — This causes immediate local pain , lasting minutes to hours . — Linear erythematous or urticarial eruptions . — Non-specific systemic effects — including nausea , vomiting and malaise — are uncommon .
oming rarely arrive at hospital before they develop cardiovascular collapse , so pre-hospital resuscitation is key . Early institution of CPR by family or bystanders appears to be associated with survival in most cases . In all patients with severe envenom-
packs are the recommended initial treatment . In a randomised controlled trial , hot water immersion was shown not to be superior to ice packs in chironex stings but may provide symptomatic relief . 4 In cases of more severe pain , adminis-
a delayed itchy papular urticarial rash develops in the same linear pattern of the sting marks after these have resolved ( see figure 3B ). Severe envenoming is rare and results in life-threatening effects that are characterised by rapid onset of cardiovascular collapse and death within 20-30 minutes .
• Irukandji-like stings : — Minimal local pain and erythema . — Delayed ( 20-30 minutes ) severe generalised pain , including abdominal , back , chest and muscular pain . — Usually associated with sympathomimetic effects , such as nausea , vomiting , headache , tachycardia , anxiety , agitation and hypertension . — Myocardial injury and pulmonary oedema may rarely occur as a result of the sympathomimetic effects .
ing , basic life support should proceed simultaneously with removal of tentacles . Wash the tentacles off with sea water or carefully remove them by hand . Cover sting sites with vinegar after tentacle removal . The aim of the vinegar is to stop further nematocyst discharge and prevent severe envenoming occurring , not to treat the pain .
ter oral or parenteral opiate analgesia . Skin reactions usually resolve without any treatment ; however , in more severe cases with necrosis , use local dressings — similar to burns dressings .
Systemic envenoming almost never develops in patients after they present to hospital . PAGE 20