Clinical Management

Consult

• Clinical flowchart
• Biological features
• Clinical entries: Venomous fish

Cardiac / Neurological effects

Signs and symptoms such as nausea, vomiting, diarrhoea, hypersalivation, hypotension, cardiac arrhythmias, cardiac arrest, respiratory distress, pulmonary oedema and muscle paralysis are listed in various combinations in case reports of venomous fish accidents.
However, in encounters with different venomous fish species, it remains to various degrees controversial how much secondary effects play a role in the overall picture such as responses related to intense / agonizing pain, circumstantial effects, e.g. near downing.Age and underlying preexisting health condition most likely are also contribute to the outcome reported.
Given the uncertainties about systemic envenoming in accidents caused by the various venomous fish, systemic venom induced cardiac effects and neurological, including autonomous effectare discussed together.

Inquire

• time of the sting
• local, possibly regional pain
• nausea, vomiting, diarrhoea

Assess

• state of consciousness

Measure

• blood pressure/pulse
• respiratory rate
• oxygen saturation (pulse oximeter)

Observe/investigate

• (very) painful puncture sites 
• swelling around the puncture site
• bleeing from the puncture site
• evidence for a deep and/or penetrating wound (thoracic/abdominal cavity/pericardial space, inner organs, blood vessels, nerves) (in particular imporant in stingray accidents)
• evidence of blood loss (haemorhagic shock)
• number of puncture sites (important in stonefish stings for assessment of the amount of venom injected and to determine the antivenom dose)
• local/regional swelling,
• clinical signs of cardiovascular disturbances, such as cardiac dysrhythmias, arterial hypotension, shock.

Immersion or showering of the affected extremity in water as hot as can be tolerated, especially if it is not possible to get immediate medical assistance (water temperature just below 45°C, temperature should be checked by a companion or with a healthy extremity in order to avoid burns, duration of treatment variable (30 - 90 min); if necessary repeatedly (Atkinson et al 2006).
Skin damage is a very serious drawback of the hot water immersion if the temperature is not carefully controlled (Abdul Jalil and Quaayum 2020; Lewis et al. 2020).
The venom, which, in addition to the physical injury, is responsible for pain and tissue destruction, is heat-labile. Controversy exists if temperatures which can be safely applied to human skin suffice to inactivate venom injected at various depth into the tissues by venomous fishes. Alternative hypotheses are modulation of pain receptors in the nervous system. The debate is ongoing, e.g., Atkinson et al. 2006; Barnett et al. 2017; Harris (2024) and Harris et al. (2025).

Diagnosis of spines, membranes and other foreign material

• X-ray examination to find foreign material that may be buried deep in the wound.
• Not all foreign material, however, is radiopaque.

Removal of spines, membranes and other foreign material

• Wound exploration in order to remove foreign matter.
• Wound exploration must be carried out along the entire wound to the depth to which the spine penetrated.
• It must be ensured that the spine did not penetrate the abdominal, pleural or pericardial cavities and that no internal organs, vessels or nerves were injured

(Carbone et al. 2024; Docter et al. 2021; Haigh et al. 2019; Negreiros et al. 2016; O’Malley et al. 2015, 2019 Palatchi et al. 2021; Trickett at al. 2008; Zeman 1989).

• Uncomplicated and properly attended wounds heal without the need of antibiotics and it is widely accepted that patients benefit from prophylactic antibiotics (Katzer et al. 2022).
• Clostridium tetani infections occur and deaths due to tetanus have been reported (Torrez et al. 2015, Rathjen and Halstead 1969).
• Large, lacerated (barbed spines!), necrotizing wounds are at high risk of getting infected and progressing in locally expanding and systemic infections (erysipelas, necrotizing fasciitis, sepsis) and chronic wounds. 
• Marine fish injury infections are caused by a wide variety of bacteria including Chromobacterium (C. violaceum), Edwardsiella, Mycobacterium marinum, Photobacterium, Shewanella Staphylococcus, Streptococcus, Vibrio (V. vulnificus). 
• Bacteria causing freshwater fish injury infections include bacteria of the genus Aeromonas (Aeromonas hydrophila) and also, Mycobacterium marinum
  (Diaz 2014, Sachett et al. 2018)

Stingray venom contains venom components that cause extensive necroses. It is important to bear this in mind in particular with deep injuries in which the venom may be introduced into regions that are inaccessible for inspection. The death of a child 6 days after a sting came about in this manner (Fenner et al. 1989b). Extensive, deep necroses that may be missed on superficial inspection of the wound can also occur with soft tissue injuries, e.g. of the extremities. Complications during wound healing are common, and wound revision as well as wound care and monitoring are important.

A general understanding of emergency medicine is required, or can be found in emergency medicine guidelines, e.g. ABCDE approach, WHO-ICRC Basic Emergency Care.

• Comprehensive ABCDE approach

• ICRC Basic Emergency Care: approach to the acutely ill and injured (SAMPLE  and ABCDE approach: first module)

• Clinical entries: Venomous fish

Antivenom indications
All patients with Stonefish envenoming.
Exceptions: only mild complaints; straightforward accident that occurred several hours previously, and if there has already been improvement of the symptoms (Sutherland and Tibballs 2001).

Complications

See

• Antivenom treatment
• Seqirus (2019)