Go to start page
V1.2.0 (T12376)
Disclaimer & Information
Search
Show Mindmap
 
Poisonous animals
 
Cnidarians (Jellyfish, Corals and Anemones)
 
Venomous fish
 
Scorpions
 
Spiders
 
Hymenopterans (Bees, Wasps and Ants)
 
Sea snakes
 
Terrestrial snakes
 
Miscellaneous animals
 
 
 
 
 
 
 
 

Diagnosis & Treatment — General practitioner / health post

 

General problems

At particular risk are: children, elderly people and patients with pre-existing conditions, such as coronary heart disease, arterial hypertension, lung disease, kidney disease, allergies (sensitisation).

Is it likely that a clinically relevant injection of venom has taken place?

D  Diagnostics

Inquire re:

  • time of the bite,
  • local pain,
  • nausea, vomiting.

Assess:

  • state of consciousness (restlessness, sleepiness, coma).

Measure:

  • blood pressure/pulse,
  • breathing (respiratory rate).

Investigate/observe:

  • local swelling,
  • local redness.

Systemic reactions:

  • sweating,
  • hypersalivation, increased bronchial secretion,
  • priapism,
  • abdominal pain (acute pancreatitis),
  • bradycardia/tachycardia/cardiac arrhythmia,
  • arterial hypotension/hypertension,
  • apical systolic murmur (mitral regurgitation), protodiastolic gallop,
  • clinical signs of pulmonary oedema,
  • clinical signs of shock,
  • clinical signs of acute hypertensive encephalopathy,
  • blurred vision, "wandering" eye movements,
  • dysphagia,
  • dysarthria,
  • pharyngeal reflex,
  • generalised muscle pain and cramps,
  • muscle weakness,
  • paralysis of the respiratory musculature (respiratory failure).

Record and measure:

  • ECG (cardiac arrhythmias, "myocardial infarction-like pattern"),
  • blood sugar.

Exclusion of a clinically relevant systemic reaction

D  Diagnostics

Monitoring for signs and symptoms of systemic envenoming for 12–24 h.

C  Comments

Severe systemic symptoms of envenoming may first arise a long time after the sting (see Parabuthus spp.; Müller 1993, Smith et al. 1983).

Who requires antivenom?

D  Diagnostics

Possibly patients with signs of systemic envenoming (see above "Is it likely that a clinically relevant injection of venom has taken place?" and Comments below).

How is the appropriate antivenom chosen?

D  Diagnostics

How are antivenoms administered and complications caused by antivenoms treated?

T  Treatment
C  Comments

Symptomatic emergency medical treatment and antivenom treatment are complementary strategies.

The aim of antivenom treatment is neutralisation of the venom.

The success of antivenom treatment depends on the quality of the antivenom, the specific properties of those venom components relevant to envenoming and the time point at which antivenom is administered.

Assessment of the importance of antivenom in the treatment of scorpion stings: very controversial discussion between expert groups in Brazil, India, Israel, Mexico, Saudi Arabia, South Africa and USA.

Brazil: Freire-Maia and Campos argue in favour of the use of antivenom and symptomatic measures for the treatment of scorpion envenoming and refer to the low mortality in the investigated patient groups. In discussions regarding the importance of antivenom in the treatment of scorpion stings, the issue of the low efficacy of commercially available antivenoms is brought up time and again. This is countered by the argument that the appropriate response should be to improve the antivenoms (Campos et al. 1979, 1980, Freire-Maia and Campos 1987, 1989).

Improvement in the clinical course of envenoming after antivenom administration in a closely monitored group of patients (Hering et al. 1993) see Biomedical database entry Tityus spp.).

India: Recent evidence suggests that recovery from Mesobuthus tamulus (=Hottentotta tamulus) stings is hastened and the time in hospital shortened by early administration of scorpion antivenom within 6h of the sting in addition to prazosin compared with prazosin alone in grade 2 scorpion evenoming. The price, however, is a problem with antivenom plus prazosin being around 10 times as expensive as prazosin alone (Bawaskar and Bawaskar 2011) (see see Biomedical database entry Mesobuthus tamulus (=Hottentotta tamulus)).

Israel: Gueron and colleagues question that antivenom can reverse the cardiac pathophysiological effects of scorpion venoms (Gueron et al. 1993, Gueron and Sofer 1994). Antivenom may be administered to patients to reverese neurotoxic effects, but should be closely observed for cardiorespiratory complications and treated appropriately (Gueron, Ilia and Margulis 2000, Sofer, Bawaskar and Gueron 2009) (see Biomedical database entry Leiurus quinquestriatus).

Mexico: In Mexico the efficacy of antivenom is rated highly (Dehesa-Davila 1989) (see Biomedical database entry Centruroides spp.).

Morocco: Antivenom is effective in decreasing circulating venom serum levels and morbidity. It is more efficient, however, when given as soon as possible after envenoming and in adequate doses (Ghalim et al. 2000) (see Biomedical database entry Androctonus mauretanicus mauretanicus and Buthus occitanus)

Saudi-Arabia: Ismail argues against excluding antivenom from the treatment of scorpion stings and advocates a combination of symptomatic and specific forms of treatment ( Ismail 1993) (see see Biomedical database entry Leiurus spp.).

Tunisia: No benefit was found in routine administration of scorpion antivenom after scorpion sting, irrespective of clinical severity (Abroug et al 1999) (see Biomedical database entry Androctonus australis and Buthus occitanus).

USA: On the basis of positive clinical experiences, antivenom is recommended by several authors for severe cases of Centruroides exilicauda envenoming (Curry et al. 1983–84, Gateau et al. 1992). Among critically ill children with neurotoxic effects of Centruroides envenoming, i.v. administration of scorpion-specific F(ab')2 antivenom resolved the syndrome within 4 hours, reduced the need for concomitant sedation with midazolam, and reduced the levels of circulating anbound venom. Generalizability of these results is limited by the age group studied and the potential for geograhic variation in scorpion venom (Boyer et al 2009) (see Biomedical database entry Centruroides spp.).

Symptomatic emergency medical treatment
1. Local pain

T  Treatment

Infiltration with a local anaesthetic (xylocaine 1%, max. 0.5 ml, without the addition of a vasoconstrictor), regional nerve block anaesthesia.

2. Respiratory disturbances due to paralysis of the respiratory musculature, cranial nerve deficits and bronchial hypersecretion

T  Treatment

Early endotracheal intubation, suctioning of bronchial secretions and artificial respiration.

3. Cardiovascular disturbances with severe arterial hypertension, pulmonary oedema and shock; possibly also hypovolaemia

T  Treatment
C  Comments

Symptomatic emergency medical treatment and antivenom treatment are complementary strategies.

The aim of symptomatic emergency medical treatment is the rapid correction of critical parameters (fluid balance, blood pressure, oxygenation etc.) and the maintenance of vital functions (respiratory, cardiovascular).

Symptomatic measures help bridge the gap until specific treatment (antivenom) can be administered and starts being effective. If no antivenom is available or if the required effect is not achieved with antivenom, the goal is to employ symptomatic measures until such time as the venom naturally starts losing its activity. 

Assessment of the importance of antivenom in the treatment of scorpion stings is controversial.

Local treatment
1. Pain

T  Treatment

See above.

2. Puncture wound, including the surrounding reaction

T  Treatment

Cleaning, disinfection and dressing of the wound at regular intervals. Immobilisation of the extremity with a splint.

If necessary, antibiotic treatment.

Tetanus

T  Treatment

Tetanus prophylaxis.