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administer it. Arrange for evacuation as soon as possible. Maintaining ABC's may be
extremely difficult without advanced knowledge and equipment.
If any signs of anaphylactic reaction are identified, rescuers carrying epinephrine
should administer the drug IM (0.3 to 0.5 mg for an adult, 0.01 mg/kg up to the adult
maximum for a child) or via pre-loaded syringes as often as necessary, depending on the
patient's status.
Local infiltration with epinephrine 1:1000 (0.1-0.3 mL) near the sting site helps impede systemic
absorption of venom. (Holgate and Church, 1993)(Marquardt and Wasserman, 1993)(Shatz, 1992).
REFERENCES:
Stinging Insects:
1)
Holgate ST and Church MK: Allergy, 27, Raven Press, New York, NY, 1993, pp
1- 27 and 29.
2)
Marquardt DL and Wasserman SI: Anaphylaxis. In: Middleton E, Reed CE,
Eliss EF et al (Eds): Allergy: Principles and Practice, Vol II, 4
th
ed, Mosby, St
Louis, MO, 1993, pp 1511-1521.
3)
Shatz GS: Anaphylaxis. In: Korenblot PE and Wedner HJ (Eds): Allergy
Theory and Practice, 2
nd
ed, WB Saunders, Philadelphia, PA, 1992, pp 229-241
B. Spider Bites: There are approximately 100,000 species of spiders worldwide, with a
density of up to two million spiders per acre in some areas. In the United States, the most
significant venomous spiders are the black widow (Latrodectus mactans) and the
fiddleback, or brown recluse (Loxosceles reclusa). The venoms of these spiders are
potent toxins with numerous antigenic components capable of causing either a systemic
manifestation or a local venom reaction.
(1)"Black widow" is itself a misnomer because only three of the five species of
widow spider (Family Therdiidae) are actually black, the others being brown and gray.
The female spider is the larger of the sexes, often measuring 1 to 1.5 cm long, with a leg
span of 4 to 5 cm. The female has a unique hourglass mark, usually red, on the ventral
abdominal surface. Newly-hatched spiders are almost entirely red, darkening with
progressive molts. Males are 3 to 5 mm long with white stripes along the lateral aspect of
the abdomen.
Only adult females can envenomate. The bite usually feels like a mild pinprick
(and may not be noticed), with subsequent slight redness that usually disappears within a
few minutes to an hour. Systemic symptoms of envenomation begin 10 to 60 minutes
after the bite of the female and are caused by the release of the neurotransmitters
acetylcholine and norepinephrine. A few minutes after the bite a small wheal appears,
followed within 15 to 60 minutes, in a minority of cases, by a band of excruciating
cramping pain that remains localized or spreads to involve the thigh, shoulder, back and
abdominal muscles. A board-like abdomen often simulates an acute abdomen. Bites on
the arm can produce chest pain that mimics a myocardial infarction. Hypertension,
respiratory distress, seizures, and, occasionally in the very young or old, cardiopulmonary
arrest are all possible complications. These symptoms frequently subside in 24 hours, but
in a few cases recur for several days to months. The very young, very old, and those with
hypertension have the greatest risk of morbidity from Latrodectus envenomation.
Reassure the patient and have him or her rest as much as possible. Assess ABC's
and monitor vital signs. Attempt to assess whether the individual was indeed bitten by a
spider or whether another process is occurring. Cold applied to the bite site may reduce
