Twenty two (18.8%) had pulmonary edema, while nine (8.5%) died. Analysis of our data suggests that cardiovascular morbidity and mortality depends upon the time between the stings hospitalization or administration of vasodilators. Current management of scorpion envenomation consists of rapid reduction of hypertension with sublingual nifedipine, postsynaptic alpha adrenergic blockade with prazosin hydrochloride, and digoxin therapy for myocardial failure. Massive pulmonary edema can be treated with sodium nitroprusside. In our setting, mortality is reduced by early hospitalization, even though specific antivenin is not available in India.
Key words: Sting, envenomation, pulmonary edema, vasodilators
Introduction
Scorpion envenomations are common in tropical and subtropical regions. They are frequent occurrences in rural India. Buthotus tamulus stings are frequent in coastal areas of India. The venom of this species is a potent autonomic stimulator. Severity of symptoms depends upon the size of the victim, season, and time lapse between sting and hospitalization. Vomiting, profuse sweating, priapism, mild pain at the sting site, local urticaria and cool extremities are early signs of autonomic stimulation due to scorpion sting. Palamneus gravimanus is a larger species present in our region, but does not cause systemic manifestations with its painful sting. High mortality from scorpion stings has been reported from Israel and Brazil. P. M. Mundle from India reported 23 deaths out of 78 cases from our region. However, no deaths occurred in Israel during 1989, irrespective of whether or not antiserum was administered. Scorpion antivenin is not available in India.
It has been argued that its availability would not reduce morbidity and mortality, because scorpion venom is very rapidly distributed to the tissue, with an estimated half life of 5–6 min, peak tissue concentrations of venom are reached within 37 min. Intravenously administered antivenom would require about 40 times longer to reach peak tissue concentrations. This might also explain the ineffectiveness of scorpion antivenom given 15 min following the injection of scorpion venom.
We report here our experience with 121 cases of scorpion envenomation studied during the period of 1986–1989.
Patients
One hundred and twenty one victims of scorpion sting were admitted to our hospital in Mahad Maharashtra state, India. They were divided into the following groups, according to major clinical features or fatal outcome
- Hypertension
- Tachycardia
- Pulmonary edema
- Fatality table 1, 2 and 3.
Sixty six victims (41 male, 25 female) ages 3 months to 65 years (average 16.2) suffered a scorpion sting 0.5–8 (average 2.9) h prior to hospitalization. Soon after the sting, all victims perspired profusely and suffered local pain of mild intensity at the site of sting, while 57 (86.4%) persons vomited once or twice soon after. Priapism was occasionally present in males who vomited. A parasternal lift and apical grade 2/6 systolic murmur of mitral regurgitation were present in 29 (43.9%) victims for 8–72 (mean 18) h. Fifty seven (86.3%) patients had cold extremities which took 6–72 (average 17.9) h to warm after oral prazosin hydrochloride , and six (9%) persons developed pulmonary edema which responded to sodium nitroprusside drip. Admission mean blood pressures ranged from 90 to 160 (mean 118.6) mm Hg.
Sublingual nifedipine (5 mg for children and 10 mg for adults) was followed by oral prazosin (250 micrograms for children and 500 micrograms for adults repeated as necessary) (Table 4).
Tachycardia
Twenty four victims (14 male, 10 female) ages 6 months to 29 years (average 10.9 ) evaluated 2.5–13 (average 6.9) h after a scorpion sting, had heart rates between 110 and 215 (average 155.5) beats per min. An apical systolic grade 2/6 murmur, prominent S3 gallop, and cold extremities persisted for 12–18 (average 12.5) h. Three persons characterized by these physical findings subsequently developed acute pulmonary edema. All cases from the tachycardia group had profuse sweating. Vomiting and priapism were reduced or absent in cases reported six or more hours after the sting. All persons recovered with oral prazosin, intravenous digoxin and aminophylline, and supplemental oxygen. Acute, severe pulmonary oedema was treated in some cases with sodium nitro–prusside. These cases were characterized by persons with hemoptysis and severe cyanosis.
Address:
H. S. Bawaskar & P. H. Bawaskar
Prabhat Colony, Savitri Marg, Mahad,
Raigad 402301, Maharashtra, India.