FIGURE 90.19 Hymenoptera capable of causing allergic reactions Triage: Systemic allergic reactions may be grouped by severity Group I consists of urticaria, generalized erythema, malaise Group II includes angioedema or two or more of the following: chest or throat tightness, nausea, vomiting, and dizziness Group III consists of dyspnea, wheezing, or stridor and two or more of the following: dysphagia, dysarthria, hoarseness, weakness, confusion, feeling of impending disaster Group IV consists of life-threatening systemic reactions, including hypotension, and shock Anaphylactic reactions secondary to insect stings occur in 0.5% to 5% of the population The barbed honeybee stinger with venom sac is avulsed and often remains in the victim’s skin It must be removed if seen Delays in removal are likely to increase the dose of venom received The method of removal of the stinger is irrelevant (scraping vs pulling vs squeezing) Management Treatment of hymenoptera stings is based on the severity of the allergic reaction Local reactions can be treated with cold compresses at the site of sting Group I reactions are treated with a second-generation antihistamine (loratidine or cetirizine) Group II and Group III reactions are treated with epinephrine 1:1,000 solution 0.01 mL/kg (maximum 0.5 mL) (or 0.01 mg/kg) IM followed by antihistamines orally Oral steroids (prednisone/prednisolone mg/kg/day or dexamethasone) are recommended These children should be observed in the hospital for 24 hours Group IV reactions may require intubation if upper airway obstruction is present Hypotension should be treated with a fluid bolus of saline or lactated Ringer solution 10 to 20 mL/kg given over 20 to 30 minutes IV epinephrine (1:10,000) should be considered if hypotension fails to respond to IM epinephrine and fluid bolus Hydrocortisone (2 mg/kg) may be given intravenously for days All children in this group should be admitted to an ICU Children who have had a group II, III, or IV reaction should be referred to an allergist for desensitization Parents of these children should keep an insect sting emergency kit The EpiPen and EpiPen Jr are spring-loaded autoinjectors triggered by placing pressure on the thigh with the instrument The pens inject 0.3 or 0.15 mg (EpiPen and EpiPen Jr, respectively) of epinephrine The pens are used as first aid in the field by the parent or guardian and are not meant to substitute for prompt definitive treatment at a medical facility Parents should receive information regarding the use of epinephrine autoinjectors and avoidance of situations and behaviors that would attract stinging insects Children attending summer camps should have an emergency dose of epinephrine with them Fire Ants Current evidence Fire ants (Solenopsis richteri and Solenopsis invicta ) cause bites and envenomations in the South and increasingly in the North The venom is an alkaloid with a direct toxic effect on mast cell membranes There is no cross-reactivity with other members of the Hymenoptera species Clinical recognition The fire ant bites with well-developed jaws and then uses its head as a pivot to inflict multiple stings There is immediate wheal and flare at the site The local reaction varies from to mm, up to 10 cm, depending on the amount of venom injected Within hours, a superficial vesicle appears After to 10 hours, the fluid in the vesicle changes from clear to cloudy (pustule), and the vesicle becomes umbilicated After 24 hours, the lesion is surrounded by a painful erythematous area that persists for to 10 days Edema, induration, and pruritus at the site occur in up to 50% of patients Occasionally, systemic reactions occur as with other Hymenoptera Management Treatment is symptomatic Local care includes ice and frequent cleansing to prevent secondary infection Topical steroids, antibacterial medications, and antihistamines not appear to prevent pustule formation Antihistamines are useful for pruritus Systemic reactions are rare and should be treated similarly to other Hymenoptera reactions TERRESTRIAL VERTEBRATES Venomous Reptiles Goals of Emergency Care Venomous substances are secreted by 15% of the United States’ 120 snake species An estimated 7,000 to 8,000 people are bitten annually by venomous snakes in the United States Emergency care is directed at providing timely antivenin therapy and expedient supportive medical care, which has dramatically reduced mortality and morbidity from poisonous snakebites Only 10 to 15 deaths are reported per year, but the morbidity in limb dysfunction and other complications is undoubtedly much higher With appropriate therapy, most longterm morbidity can be prevented CLINICAL PEARLS AND PITFALLS Identification of the snake may not be possible, but snakebite victims should be treated based on clinical symptoms Extraction of venom is not usually helpful Current Evidence The pediatric population, especially males aged to 19 years, accounts for a disproportionately large number of snake-bite victims The highest incidence occurs in the Southeast and Southwest, between April and October, although venomous snakebites occur at least sporadically in most states The poisonous snakes indigenous to the United States are members of the Crotalidae (pit viper) or Elapidae (coral snake) families ( Table 90.21 ) The rattlesnake, water moccasin, and copperhead are pit vipers and are responsible for 99% of venomous snakebites The coral snake is the only member of the Elapidae family in this country and, along with imported exotic snakes, accounts for the remaining 1% of serious snakebites Cobras are also members of the Elapidae family but are not native to the United States Snakebites have been associated with alcohol/drug intoxication, and bites are often provoked when people try to catch a wild snake or while caring for captive snakes ... Emergency Care Venomous substances are secreted by 15% of the United States’ 120 snake species An estimated 7,000 to 8,000 people are bitten annually by venomous snakes in the United States Emergency. .. and behaviors that would attract stinging insects Children attending summer camps should have an emergency dose of epinephrine with them Fire Ants Current evidence Fire ants (Solenopsis richteri... referred to an allergist for desensitization Parents of these children should keep an insect sting emergency kit The EpiPen and EpiPen Jr are spring-loaded autoinjectors triggered by placing pressure