CURRENT Essentials of Critical Care.pdf

256 Current Essentials of Critical Care■■■Spider & Scorpion BitesEssentials of Diagnosis• Black widow spider bite initially painless, after 10–60 minutes,pain, muscle spasms, headache, nausea, vomiting, rigidity of abdominalwall; symptoms peak 2–3 hours after bite, may persist24 hours• Brown recluse spider bites have pain 1–4 hours after bite, erythemawith pustule or bull’s-eye pattern; ulcer may form afterseveral days; rarely systemic reactions 1–2 days later, includinghemolysis, hemoglobinuria, jaundice, renal failure, pulmonaryedema, disseminated intravascular coagulation• Scorpion bites cause severe pain without erythema, swelling;rare systemic reactions include restlessness, jerking, nystagmus,hypertension, diplopia, confusion, seizuresDifferential Diagnosis• Acute abdomen (black widow spider)• Insect bites, including ticks• Staphylococcal, streptococcal skin infections• Chronic herpes simplex, varicella-zoster• Vasculitis, other skin disordersTreatment• Black widow spider bites: pain relief with intravenous opioids,antivenom in severe cases, supportive care if organ failure• Brown recluse spider bites: ice to local area, supportive care,debridement if severe ulceration forms at bite area• Scorpion bites: ice to local area; antivenom in severe cases; donot use opioids, as they might potentiate venom toxicity■ PearlWhen trying to determine if bite is from a spider or other type of insect,spiders usually only bite once, whereas other insects bite multipletimes.ReferenceAnderson PC: Spider bites in the United States. Dermatol Clin 1997;15:307.[PMID: 9098639]