Diagnosis & Treatment — First aid / lay people
- The patient is in the water (risk of drowning),
- loss of consciousness.
- Take the patient to land.
- Pain management (see below).
- Calm the patient.
- Place the patient in a stable lateral position, or possibly the Trendelenburg position (shock position).
Pain following injuries from venomous fish as well as anxiety (fear of death) play an important role and have an additional negative influence on the clinical course after an accident. Loss of consciousness after an accident with a venomous animal can have many causes. It is important to place the patient in a stable lateral position to avoid aspiration. Only a few venomous fish can cause clinically significant systemic envenoming or severe injuries. Respiratory or cardiovascular complications may also be caused by drowning or near-drowning.
If peripheral circulatory failure is present, the shock position may improve the patient's condition. If resuscitation is necessary, it is only in exceptional cases that lay people will be sufficiently well trained to be able to intervene.
How can the species that caused the acutely dangerous accident be identified?
- indirectly from the circumstances of the accident,
- indirectly from the consequences of the accident: see Comments below.
Because of the great variety of puncture wounds that can occur while bathing, diving or fishing, the layperson must decide whether or not this is a serious injury on the basis of his/her own knowledge and the extent of the symptoms. Usually the animal that caused the accident cannot be identified morphologically. The layperson must thus distinguish between:
- stings that cause pain; all venomous fish can cause this type of injury, as well as sea urchins and starfish, among others;
- stings that cause pain as well as systemic effects; this type of sting is caused by Stonefishes, Lionfishes and Catfishes; however, other venomous fish stings may be so painful that the pain alone can lead to systemic reactions, such as sweating, tachycardia and collapse;
- stings that cause pain as well as extensive soft tissue and penetrating injuries; the Stingrays belong to this group.
Immersion of the affected extremity in water as hot as can be tolerated, if it is not possible to get immediate medical assistance (water temperature approx. 45°C; temperature should be checked by a companion or with a healthy extremity in order to avoid burns; duration of treatment if need be >30 min).
Besides physical injuries, the venom of venomous fish also causes pain and tissue destruction. It is believed to be heat-labile. It is assumed that the hot water treatment may have an inactivating effect on the venom. However, this method is controversial, due to the risk of additional tissue damage. Its efficacy has not yet been documented in controlled studies.
Painful, extensive puncture wounds
- Superficial injury: possibly the hot water method (see above);
- deep injuries: no intervention; seek medical care as quickly as possible;
- penetrating injuries: if a large vessel has been damaged, stanch the bleeding with the help of a tourniquet or by compression proximal to the injury or in the region of the injury.
Which patients need to be seen by a doctor or hospitalised?
- All patients who have no tetanus vaccine protection, for a first vaccination or a booster shot,
- patients with strong pain, for effective pain management,
- patients with extensive injuries, for wound care,
- patients with deep injuries, for exploration of the wound and wound care,
- patients with systemic signs of envenoming, for investigations, monitoring and possibly antivenom treatment (Stonefishes).