Emergency & clinical flowcharts
| Signs and symptoms1 |
Emergency medical treatment | Identification of the cause3 |
Antivenom4 | |||
| Possible cause2 |
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| Nausea, vomiting, abdominal pain, diarrhoea, urticaria, angio-oedema, bronchospasm, arterial hypotension (autopharmacological effects of the venom, including anaphylaxis) | Treatment of anaphylactic/anaphylactoid reactions. |
In North America, with regard to antivenom treatment, only crotalids and elapids (M. fulvius) need to be distinguished as the cause Identification strategies: 1. Morphological identification key (if snake is available for identification) 2. Narrowing down the cause with the aid of indirect criteria: |
Antivenom efficacy5
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| Agkistrodon sp. Crotalus sp. Sistrurus sp. |
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| Generalised oedema → hypovolaemia → hypovolaemic shock (autopharmacological effect of the venom: increased capillary permeability) |
Treatment of the hypovolaemia/hypovolaemic shock |
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| Crotalus sp. | ||||||
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Pulmonary oedema, |
Treatment of the non-cardiogenic pulmonary oedema, treatment of the cerebral oedema |
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| Crotalus sp. | ||||||
| Extensive local swelling possibly involving the trunk → hypovolaemia → hypovolaemic shock (local effect of the venom: regionally increased capillary permeability) |
Treatment of the hypovolaemia/hypovolaemic shock |
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| Agkistrodon sp. Crotalus sp. Sistrurus sp. |
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| Systemic bleeding → hypovolaemia → haemorrhagic shock (haemostatic effects of the venom) |
Treatment of the haemorrhage-induced hypovolaemia/haemorrhagic shock | |||||
| ((Agkistrodon sp.)) (Crotalus sp.) (Sistrurus sp.) |
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| Intracranial bleeding → focal neurological deficits, coma, meningismus (haemostatic effects of the venom) |
Treatment of intracranial bleeding | |||||
| ((Agkistrodon sp.)) (Crotalus sp.) (Sistrurus sp.) |
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| Cranial nerve deficits, paralysis of the skeletal musculature including the respiratory musculature → respiratory insufficiency, respiratory failure (neurological effects of the venom) |
Treatment of the respiratory insufficiency/respiratory failure: acetylcholinesterase inhibitors, endotracheal intubation and artificial respiration |
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| Myalgia: spontaneous, with active/passive movement and upon pressure, ECG changes (hyperkalaemia), signs of paralysis, urine colour (differential diagnosis haemoglobinuria), renal failure (muscular effect of the venom: rhabdomyolysis) |
Treatment of the hyperkalaemia, prevention and treatment of the acute renal failure, treatment of the respiratory insufficiency/respiratory failure
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| Crotalus horridus | ||||||
| Myocardial symptoms, cardiac dysrhythmias, ischaemia (ECG), cardiac insufficiency, heart failure (usually secondary, rarely primary cardiac effects of the venom) |
Treatment of the cardiac disturbance |
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| Acute renal failure (usually secondary, rarely primary renal effects of the venom) |
Treatment of the acute renal failure |
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| No/insufficient data, no clinically relevant cases of envenoming known | ||||||
| 1 |
See also the Clinical flowchart as a guide to the dynamics of envenoming. |
| 2 | Taxonomic name without parentheses/(in parentheses)/((in double parentheses)): these signs and symptoms are regularly/(rarely)/((questionably)) observed following bites by these species. |
| 3 | Identification of the cause insofar as is necessary for differential treatment (see "Essentials of the management of envenoming and poisoning: 3. What level of identification of the animal that caused the accident is necessary?"). |
| 4 | See "Essentials of the management of envenoming and poisoning: 9. How is the appropriate antivenom chosen? When is it administered?". |
| 5 | If clinical information regarding the efficacy of an antivenom is available, it is presented in the relevant Biomedical database entry. |
| 6 | These cases are also dealt with in accordance with the corresponding problem-oriented section "Diagnosis & Treatment". |