The Creepy and Crawling: The Creepy and Crawling: Bites and Stings in North Bites and Stings in North

AmericaAmericaDr. Rebecca C. Bowers FACEPDr. Rebecca C. Bowers FACEP

Assistant ProfessorAssistant ProfessorDepartment of Emergency MedicineDepartment of Emergency Medicine

University of KentuckyUniversity of Kentucky

Learning ObjectivesLearning Objectives

Discuss scope of problem in the US and worldwideDiscuss scope of problem in the US and worldwide Recognize the major groups of animals that pose an Recognize the major groups of animals that pose an

envenomation threatenvenomation threat Gain an understanding of the prehospital and hospital Gain an understanding of the prehospital and hospital

management of North American snake envenomationsmanagement of North American snake envenomations Gain an understanding of the prehospital and hospital Gain an understanding of the prehospital and hospital

management of North American arachnid envenomationmanagement of North American arachnid envenomation Gain an understanding of prehospital and hospital Gain an understanding of prehospital and hospital

management of Hymenoptera envenomationmanagement of Hymenoptera envenomation Discuss the disposition of envenomation victimsDiscuss the disposition of envenomation victims

HymenopteraHymenopteraEnvenomationEnvenomation

North American OffendersNorth American Offenders

Bees and Wasps Bees and Wasps Bees: Honeybees, bumblebees, and africanized Bees: Honeybees, bumblebees, and africanized

honeybeeshoneybees Wasps: true wasps, yellow jackets, hornetsWasps: true wasps, yellow jackets, hornets Found throughout USA. AHBs found in SouthwestFound throughout USA. AHBs found in Southwest

AntsAnts Imported red fire antImported red fire ant Imported from South America. Found from Virginia to Imported from South America. Found from Virginia to

TexasTexas Native ant speciesNative ant species

Epidemiology Epidemiology Scope of the ProblemScope of the Problem

In 2005 AAPCC reported 10,792 bee and wasp In 2005 AAPCC reported 10,792 bee and wasp exposuresexposures

1200 required a hospital visit with only 1 death1200 required a hospital visit with only 1 death Very underreportedVery underreported 2100 fire ant exposures with 250 requiring a 2100 fire ant exposures with 250 requiring a

hospital visit and no deathshospital visit and no deaths AAAI survey 20,750 fire ant exposures AAAI survey 20,750 fire ant exposures

annuallyannually

Venom PathophysiologyVenom Pathophysiology

Bees and WaspsBees and Wasps Bees: Melittin, hyaluronidase, mast-cell Bees: Melittin, hyaluronidase, mast-cell

degranulation proteindegranulation protein Wasps: very similar with addition of Ach and Wasps: very similar with addition of Ach and

serotoninserotonin Red fire antsRed fire ants

Piperidine alkaloid causing histamine release and Piperidine alkaloid causing histamine release and skin necrosisskin necrosis

Cytotoxic and hemotoxic propertiesCytotoxic and hemotoxic properties

Taken from WebMD.comTaken from WebMD.com

Clinical SyndromesClinical Syndromes

Bees and WaspsBees and Wasps Small, local pruritic skin lesion. Larger local Small, local pruritic skin lesion. Larger local

reactions >5cm do occur and may last longer. reactions >5cm do occur and may last longer. Occasionally a mild systemic reaction occurs with Occasionally a mild systemic reaction occurs with

n/v, diarrhea, diffuse urticarial skin lesions. n/v, diarrhea, diffuse urticarial skin lesions. Very rarely, a victim will present with full blown Very rarely, a victim will present with full blown

anaphylaxisanaphylaxis Massive envenomation >50 stings CV collapseMassive envenomation >50 stings CV collapse Delayed systemic toxicity: This includes hemolysis, Delayed systemic toxicity: This includes hemolysis,

thrombocytopenia, liver dysfunction, and thrombocytopenia, liver dysfunction, and rhabdomyolysis with subsequent renal failurerhabdomyolysis with subsequent renal failure

Red fire antsRed fire ants Multiple stings rule rather than exceptionMultiple stings rule rather than exception Hundreds of pustules at bite sitesHundreds of pustules at bite sites Burning pain at each lesionBurning pain at each lesion 25% of population in endemic areas has 25% of population in endemic areas has

hypersensitivity hypersensitivity Resultant anaphylactic reaction possibleResultant anaphylactic reaction possible Systemic venom toxicity after mass envenomationSystemic venom toxicity after mass envenomation

TreatmentTreatment

Prehospital: Prehospital: Airway management, nebulizers, epinephrine, Airway management, nebulizers, epinephrine,

fluidsfluids Note number and location of stings, progressionNote number and location of stings, progression

Hospital: Hospital: Same with addition of steroids and H1 and H2 Same with addition of steroids and H1 and H2

blockers, pressors as needed for CV support, blockers, pressors as needed for CV support, tetanus tetanus

Massive envenomation requires monitoring for Massive envenomation requires monitoring for rhabdo, hemolysis, ARF, and liver failurerhabdo, hemolysis, ARF, and liver failure

DispositionDisposition

Local: discharge after symptomatic careLocal: discharge after symptomatic care Mild allergic reaction: discharge after 6 hours Mild allergic reaction: discharge after 6 hours

with 3 days of oral antihistamines and oral with 3 days of oral antihistamines and oral steroidssteroids

Moderate to anaphylaxis: admission, Epi-pen, Moderate to anaphylaxis: admission, Epi-pen, allergist referral, medic-alert bracelet allergist referral, medic-alert bracelet

Mass envenomation: admission even if Mass envenomation: admission even if asymptomatic due to delayed systemic toxicityasymptomatic due to delayed systemic toxicity

ReptilianReptilian

EnvenomationEnvenomation

North American OffendersNorth American Offenders

Crotalidae or Pit Vipers Crotalidae or Pit Vipers RattlesnakeRattlesnake CottonmouthCottonmouth CopperheadCopperhead

ElapidaeElapidae Coral SnakeCoral Snake

Multiple species of each located all over the Multiple species of each located all over the USA except Maine, Alaska and HawaiiUSA except Maine, Alaska and Hawaii

EpidemiologyEpidemiologyScope of the ProblemScope of the Problem

In 2005 AAPCC reported 2900 pit viper bites In 2005 AAPCC reported 2900 pit viper bites with 1875 being evaluated at a hospital and 6 with 1875 being evaluated at a hospital and 6 deaths. 171 considered life-threatening. Not all deaths. 171 considered life-threatening. Not all reported. 25% of bites are “dry bites”reported. 25% of bites are “dry bites”

Reported 58 coral snake bites with 6 life-Reported 58 coral snake bites with 6 life-threatening and no deathsthreatening and no deaths

Morbidity fairly high with lost productivity Morbidity fairly high with lost productivity due to pain and reduced functiondue to pain and reduced function

Worldwide a much bigger problemWorldwide a much bigger problem Best estimates are as high as 1.8 million bites Best estimates are as high as 1.8 million bites

per year with 94,000 deathsper year with 94,000 deaths Biggest problem in southern Asia and Sub-Biggest problem in southern Asia and Sub-

Saharan Africa due to lack of antivenin, rural Saharan Africa due to lack of antivenin, rural locales, and much higher incidence of lethal locales, and much higher incidence of lethal speciesspecies

Venom PathophysiologyVenom Pathophysiology

Hemotoxic venom (Pit Vipers)Hemotoxic venom (Pit Vipers) One of most complex venomsOne of most complex venoms Thrombin-like enzymes: coagulopathyThrombin-like enzymes: coagulopathy Phospholipases: platelet dysfunctionPhospholipases: platelet dysfunction Metalloproteinases:leaky vasculature with edema Metalloproteinases:leaky vasculature with edema

and ecchymosisand ecchymosis Bradykinin: hypotension, N/V/D, painBradykinin: hypotension, N/V/D, pain

Neurotoxic venom (Coral Snake and Mojave Neurotoxic venom (Coral Snake and Mojave Rattlesnake)Rattlesnake) Disrupts neuromuscular transmission by blocking Disrupts neuromuscular transmission by blocking

Ach receptors with resultant weakness, Ach receptors with resultant weakness, paresthesias, and respiratory paralysisparesthesias, and respiratory paralysis

Taken from emedicine article published by University of TennesseeTaken from emedicine article published by University of Tennessee

Pediatric Emergency Medicine PracticePediatric Emergency Medicine PracticeMay 2007 Vol. 4 No. 5May 2007 Vol. 4 No. 5

Pit Viper TreatmentPit Viper Treatment

PrehospitalPrehospital ABCsABCs Assess for systemic symptomsAssess for systemic symptoms Note bite site, bite time and snake typeNote bite site, bite time and snake type Mark initial area with time and follow progressionMark initial area with time and follow progression Elevate to level of heartElevate to level of heart Compression dressing or pressure-immobilizationCompression dressing or pressure-immobilization Transport immediately to facility with antiveninTransport immediately to facility with antivenin

Do Not…..Do Not…..

PerformPerform Cryotherapy (the old ice bucket)Cryotherapy (the old ice bucket) Electrotherapy (jumper cables…I’m not kidding)Electrotherapy (jumper cables…I’m not kidding) Cut and suck methodCut and suck method Sawyer extractorSawyer extractor Tourniquets Tourniquets

TreatmentTreatment

HospitalHospital ABCsABCs Note progressionNote progression Labs Labs Grade envenomationGrade envenomation Determine need for CroFab (see next slide)Determine need for CroFab (see next slide) Tetanus updateTetanus update

Weant KA, Johnson PN, Weant KA, Johnson PN, Bowers RC,Bowers RC, Armitstead JA; Evidence-Based, Multidisciplinary Approach to the Development of a Armitstead JA; Evidence-Based, Multidisciplinary Approach to the Development of a Crotalidae Polyvalent Antivenin (CroFab) Protocol at a University Hospital. Crotalidae Polyvalent Antivenin (CroFab) Protocol at a University Hospital. The Annals of PharmacotherapyThe Annals of Pharmacotherapy 2010; 2010; 44:xxxx.44:xxxx.

Weant KA, Johnson PN, Weant KA, Johnson PN, Bowers RC,Bowers RC, Armitstead JA; Evidence-Based, Multidisciplinary Approach to the Development of a Armitstead JA; Evidence-Based, Multidisciplinary Approach to the Development of a Crotalidae Polyvalent Antivenin (CroFab) Protocol at a University Hospital. Crotalidae Polyvalent Antivenin (CroFab) Protocol at a University Hospital. The Annals of PharmacotherapyThe Annals of Pharmacotherapy 2010; 2010; 44:xxxx.44:xxxx.

To cut or not to cut….To cut or not to cut….

Fasciotomy very rarely indicated Fasciotomy very rarely indicated Mimics compartment syndromeMimics compartment syndrome Usually subcutaneous edemaUsually subcutaneous edema Antivenin will almost always reverse true Antivenin will almost always reverse true

compartment syndromecompartment syndrome Only proceed to fasciotomy if elevated Only proceed to fasciotomy if elevated

pressure sustained and confirmed with pressure sustained and confirmed with measurementmeasurement

A word on CroFab….A word on CroFab….

Only FDA approved Pit Viper antivenin Only FDA approved Pit Viper antivenin currentlycurrently

Other good antivenins used in Central and Other good antivenins used in Central and South America for pit vipersSouth America for pit vipers

Much less expensiveMuch less expensive Do work on North American speciesDo work on North American species Used by local venom expertUsed by local venom expert

TreatmentTreatment

Coral Snakes (Elapids)Coral Snakes (Elapids) Respiratory support as neededRespiratory support as needed Return of muscular function can take weeks Return of muscular function can take weeks

requiring prolonged intubationrequiring prolonged intubation Antivenin is available in USA but whole IgG so no Antivenin is available in USA but whole IgG so no

longer producedlonger produced Other possibilities include mexican product and Other possibilities include mexican product and

Tiger snake antivenin from AustraliaTiger snake antivenin from Australia

DispositionDisposition

Pit Viper (Crotalid)Pit Viper (Crotalid) Observe 8 hours. If no symptoms then may Observe 8 hours. If no symptoms then may

dischargedischarge No CroFab warranted but envenomated: Discharge No CroFab warranted but envenomated: Discharge

with lab and MD follow up 24-48 hourswith lab and MD follow up 24-48 hours CroFab given: admission to floor versus ICU CroFab given: admission to floor versus ICU

depending on clinical scenariodepending on clinical scenario

Coral Snake (Elapid)Coral Snake (Elapid) Admission warranted even if asymptomaticAdmission warranted even if asymptomatic Some argue to give antivenin empirically given Some argue to give antivenin empirically given

severity of envenomation severity of envenomation

ArachnidArachnidEnvenomationEnvenomation

North American OffenderNorth American Offender

Centruroides exilicauda or the Bark ScorpionCentruroides exilicauda or the Bark Scorpion Found in Southwestern USA mainly in Found in Southwestern USA mainly in

ArizonaArizona Few in Texas, Northern Mexico, and areas of Few in Texas, Northern Mexico, and areas of

CaliforniaCalifornia

EpidemiologyEpidemiologyScope of the ProblemScope of the Problem

In 2005 AAPCC reported 14,521 reports of In 2005 AAPCC reported 14,521 reports of scorpion envenomationscorpion envenomation

20 victims felt to have life threatening 20 victims felt to have life threatening outcomesoutcomes

No deaths reported that yearNo deaths reported that year Almost all lethal envenomations are children Almost all lethal envenomations are children

or occur outside the USor occur outside the US

Venom PathophysiologyVenom Pathophysiology

No cytotoxinsNo cytotoxins 2 potent neurotoxins enhance membrane 2 potent neurotoxins enhance membrane

depolarization and prolong action potentialdepolarization and prolong action potential Over stimulation of parasympathetic and Over stimulation of parasympathetic and

sympathetic nervous system with Ach and sympathetic nervous system with Ach and catecholamine releasecatecholamine release

Clinical SyndromeClinical Syndrome

+ tap test over sting site+ tap test over sting site Autonomic dysfunctionAutonomic dysfunction Fasciculations and roving eye movementsFasciculations and roving eye movements Uncontrolled limb movementsUncontrolled limb movements Increased secretions including bronchorrhea Increased secretions including bronchorrhea Mild envenomation: adrenergic syndromeMild envenomation: adrenergic syndrome Severe envenomation: cholinergic syndromeSevere envenomation: cholinergic syndrome

Additional treatmentsAdditional treatments

Sympatholytic antihypertensive agents for Sympatholytic antihypertensive agents for hypertensionhypertension

Atropine may be used to control secretionsAtropine may be used to control secretions

AntiveninAntivenin

Antivenin:Antivenin: Previous goat serum derived has expiredPrevious goat serum derived has expired New drug Anascorp manufactured in Mexico is New drug Anascorp manufactured in Mexico is

being trialed in Arizonabeing trialed in Arizona Using since 2004 and over 1500 patients treatedUsing since 2004 and over 1500 patients treated Still pending FDA approvalStill pending FDA approval

DispositionDisposition

Most adults require supportive treatment onlyMost adults require supportive treatment only Children more likely to suffer with Children more likely to suffer with

neuromuscular dysfunction and require ICU neuromuscular dysfunction and require ICU admission and antiveninadmission and antivenin

North American OffendersNorth American Offenders

Only 2 medically significant spiders in the Only 2 medically significant spiders in the USAUSA

Loxosceles reclusa or the Brown RecluseLoxosceles reclusa or the Brown Recluse Found mainly in central and southern US decreasing Found mainly in central and southern US decreasing

towards the coasttowards the coast

Latrodectus or the Black Widow SpiderLatrodectus or the Black Widow Spider Found throughout the USFound throughout the US

EpidemiologyEpidemiologyScope of the Problem Scope of the Problem

In 2005 the AAPCC reported 2236 recluse In 2005 the AAPCC reported 2236 recluse bites with 14 being life-threatening. High bites with 14 being life-threatening. High morbiditymorbidity

Over last 20 years 40,000 Black Widow Over last 20 years 40,000 Black Widow envenomations have been reported to AAPCC. envenomations have been reported to AAPCC. Mortality highest in childrenMortality highest in children

Venom PathophysiologyVenom Pathophysiology

Black Widow (Latrodectus)Black Widow (Latrodectus) No cytotoxinsNo cytotoxins Alpha-latrotoxin most importantAlpha-latrotoxin most important

Decreases reuptake of acetylcholine at NMJDecreases reuptake of acetylcholine at NMJ Also epinephrineAlso epinephrine

Brown Recluse (Loxosceles)Brown Recluse (Loxosceles) Many cytotoxic components and inflammatory Many cytotoxic components and inflammatory

mediatorsmediators Sphingomyelinase D as well prostaglandins, Sphingomyelinase D as well prostaglandins,

leukotrienes, and thromboxanesleukotrienes, and thromboxanes

Pediatric Emergency Medicine PracticePediatric Emergency Medicine PracticeMay 2007 Vol. 4 No. 5May 2007 Vol. 4 No. 5

Brown RecluseBrown Recluse Local tissue destructionLocal tissue destruction Systemic loxoscelismSystemic loxoscelism

24-72 hours flu-like illness24-72 hours flu-like illness Hemolysis, DIC, ARF, shock, pulmonary edemaHemolysis, DIC, ARF, shock, pulmonary edema

Verified Brown Recluse Bite Verified Brown Recluse Bite Bites of Brown Recluse Spiders and Suspected Necrotic ArachnidismBites of Brown Recluse Spiders and Suspected Necrotic Arachnidism

David L. Swanson, M.D., and Richard S. Vetter, M.S.David L. Swanson, M.D., and Richard S. Vetter, M.S.N Engl J Med 2005; 352:700-707N Engl J Med 2005; 352:700-707February 17, 2005February 17, 2005

Treatment of Brown RecluseTreatment of Brown Recluse

Delayed surgical excisionDelayed surgical excision No to DapsoneNo to Dapsone No to SteroidsNo to Steroids No to nitroglycerineNo to nitroglycerine No to HBONo to HBO Systemic Loxoscelism requires supportive treatmentSystemic Loxoscelism requires supportive treatment AntiveninAntivenin

Rabbit-derived Fab fragmentsRabbit-derived Fab fragments Must be administered within 4 hoursMust be administered within 4 hours Typical delay makes this impracticalTypical delay makes this impractical

Pediatric Emergency Medicine PracticePediatric Emergency Medicine PracticeMay 2007 Vol. 4 No. 5May 2007 Vol. 4 No. 5

Pediatric Emergency Medicine PracticePediatric Emergency Medicine PracticeMay 2007 VOl.4 No. 5May 2007 VOl.4 No. 5

Black Widow antiveninBlack Widow antivenin

Whole IgG with high incidence of serum Whole IgG with high incidence of serum sickness and hypersensitivitysickness and hypersensitivity

Reserved for severe autonomic dysfunction Reserved for severe autonomic dysfunction and painand pain

A Fab antivenin is being testedA Fab antivenin is being tested

DispositionDisposition

Black Widow Black Widow May discharge after 6 hours if asymptomaticMay discharge after 6 hours if asymptomatic Admission otherwise for IV opiates and benzosAdmission otherwise for IV opiates and benzos

Brown RecluseBrown Recluse Most can be discharged with follow-up for long-Most can be discharged with follow-up for long-

term wound careterm wound care ICU admission for systemic syndromeICU admission for systemic syndrome

Be careful out there!!!Be careful out there!!!

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QuestionsQuestions

1.1. Bites and Stings-Snakes, spiders, and scorpions in the United States. Bites and Stings-Snakes, spiders, and scorpions in the United States. Pediatric Emergency Medicine Practice May 2007 Vol. 4 No. 5Pediatric Emergency Medicine Practice May 2007 Vol. 4 No. 5

2.2. Hymenoptera envenomation: Bees, Wasps, and Ants. Pediatric Hymenoptera envenomation: Bees, Wasps, and Ants. Pediatric Emergency Medicine Practice June 2008 VOl. 5 No.6Emergency Medicine Practice June 2008 VOl. 5 No.6

3.3. Antivenom for Critically Ill Children with Neurotoxicity from Scorpion Antivenom for Critically Ill Children with Neurotoxicity from Scorpion Stings. NEJM 2009; 3360:2090-8.Stings. NEJM 2009; 3360:2090-8.

4.4. Bites of Brown Recluse Spiders and Suspected Necrotic Arachnidism. Bites of Brown Recluse Spiders and Suspected Necrotic Arachnidism. NEJM 2005; 352:700-7NEJM 2005; 352:700-7

5.5. The global burden of snakebite: a literature analysis and modeling basedThe global burden of snakebite: a literature analysis and modeling based on regional estimates of envenoming and deaths on regional estimates of envenoming and deaths. PLoSMed. 2008 Nov 4;5(11):e218. PLoSMed. 2008 Nov 4;5(11):e218

6.6. Evidence-Based, Multidisciplinary Approach to the Development of a Evidence-Based, Multidisciplinary Approach to the Development of a Crotalidae Polyvalent Antivenin (CroFab) Protocol at a University Crotalidae Polyvalent Antivenin (CroFab) Protocol at a University Hospital. The Annals of Pharmacotherapy March 2010 Vol. 44Hospital. The Annals of Pharmacotherapy March 2010 Vol. 44