Snakebite and Spiderbite Clinical Management Guidelines Third Edition

Transcription

1 Guidelie Miistry of Health, NSW 73 Miller Street North Sydey NSW 2060 Locked Mail Bag 961 North Sydey NSW 2059 Telephoe (02) Fax (02) Sakebite ad Spiderbite Cliical Maagemet Guidelies Third Editio Director-Geeral Documet Number GL2014_005 Publicatio date 17-Mar-2014 Fuctioal Sub group Cliical/ Patiet Services - Critical care Cliical/ Patiet Services - Medical Treatmet space space space Summary Revised cliical resource documet which provides iformatio ad advise o the maagemet of patiets with actual or suspected sakebite or spiderbite, ad the appropriate levels, type ad locatio of stored ativeom i NSW health facilities. These are cliical guidelies for best cliical practice which are ot madatory but do provide essetial cliical support. Replaces Doc. No. Sakebite & Spiderbite Cliical Maagemet Guidelies NSW [GL2007_006] Author Brach Agecy for Cliical Iovatio Brach cotact Agecy for Cliical Iovatio Applies to Local Health Districts, Board Govered Statutory Health Corporatios, Chief Executive Govered Statutory Health Corporatios, Specialty Network Govered Statutory Health Corporatios, Affiliated Health Orgaisatios, Commuity Health Cetres, Govermet Medical Officers, NSW Ambulace Service, Miistry of Health, Private Hospitals ad Day Procedure Cetres, Public Health Uits, Public Hospitals Audiece Cliicial Nursig, Medical, Allied Health Staff, Admiistratio, ED, Itesive Care Uits Distributed to Public Health System, Divisios of Geeral Practice, Govermet Medical Officers, Miistry of Health, Private Hospitals ad Day Procedure Cetres, Tertiary Educatio Istitutes Review date 17-Mar-2019 Policy Maual Patiet Matters File No. 12/4133 Status Active

2 FIVE Spiderbite Guidelies for Assessmet ad Maagemet Itroductio Red-back spider eveomig or latrodectism is characterised by severe local or regioal pai associated with o-specific systemic symptoms ad less commoly autoomic effects. Fuel-web spider eveomig is rare, but causes severe ad potetially life-threateig eurotoxicity. There are specific ativeoms for these two sydromes. All other spiders will almost always oly cause mior effects ad require symptomatic treatmet. There are also may other stigig or bitig creatures which are briefly covered i the appedices, but for which o guidelies have bee developed. Epidemiology ad cliical effects Spider bites occur more commoly i the warmer moths of the year. The majority of fuel-web spider bites have bee reported i Sydey, the Cetral Coast ad Newcastle. Most local effects are a result of simple mechaical trauma from the bite. Pai or discomfort occurs i almost every spider bite ad the absece of pai suggests the patiet has ot bee bitte. Most patiets will recall the pai of the bite ad ofte see or catch the spider after feelig the pai of the bite. Other local effects are a direct result of the mechaical trauma ad iclude fag marks, bleedig ad local erythema. Larger spiders will cause more trauma with bleedig fag marks (big black spiders) compared with miimal evidece of the bite with smaller spiders, such as red-back spiders. Allergic reactios have ot bee reported followig spider bites. Hypersesitivity reactios after a bite suggests bees, wasps or ats are the culprit. Secodary ifectio is also rare (< 1%) with spider bites. Specific features of fuel-web ad red back bite are discussed below. Other spiders do ot cause severe systemic eveomig. Cliical assessmet I cotrast to sakebite, it is commo for people to suspect spiderbite without observig a spider bitig. Thus, the iitial task is to establish if a spider was see to bite, whether the culprit was collected ad the timig of the sigs ad symptoms attributed to the bite. I most cofirmed cases, the patiet will preset soo after a defiite bite. Relevat history The followig lie of questioig may be useful, with the purpose of idetifyig if a fuel-web spider or related species eeds to be cosidered Was a spider see to bite (?multiple bites) OR were the circumstaces such that a bite might have occurred? Whe did the patiet get bitte (elapsed time)? Descriptio of spider if possible (colour, size, shape) Geographic locatio that the icidet occurred Timig ad type of first aid ad activity after the bite Type ad timig of symptoms; specifically ask about tiglig aroud lips, togue fasciculatio, excessive lacrimatio, salivatio, piloerectio, hypertesio, ausea, dyspoea (pulmoary oedema), impaired coscious state There are o specific diagostic tests for fuel web spider or ay other spider eveomig. Examiatio should iclude lookig for typical features of redback spider ad fuel web spider eveomig. PAGE 20 NSW HEALTH Sakebite & Spiderbite Cliical Maagemet Guidelies Third Editio

3 Defiite spider bites are the maaged i oe of three cliical pathways: 1. Big black spider bites. This icludes potetial bites by fuel-web spiders, but also trapdoor spiders, mouse spiders ad other mygalomorphs (large, primitive spiders). Distiguishig fuel-web spiders from other mygalomorph spiders should oly be doe by expert arachologists. All bites by big black spiders i easter Australia should be maaged as suspected fuel-web spider bites for the first 4 hours after beig bitte. 2. Red-back spiders (Latrodectus hasseltii). The defiig feature of red-back spider eveomig is severe pai, which may be associated with ospecific systemic symptoms. It develops gradually ad is ot life-threateig. Treatmet is primarily for symptomatic relief ad ca iclude aalgesia ad/or the red-back spider ativeom. Most people ca idetify a red-back spider with reasoable accuracy. 3. Other spiders. Bites by all other Australia spiders oly cause mior effects. If a patiet has ot bee bitte by either a big black spider or red-back spider they ca be reassured because o major eveomig will occur. Some patiets preset with ski lesios or ecrotic ulcers they attribute to a spider bite. Necrotic ulcers have ot bee reported from cofirmed spider bites i Australia. The diagosis ad ivestigatio should be focused o other importat causes of ulcers icludig ifectio, immuological, iflammatory, vascular ad eoplastic aetiologies. Red-back spider eveomig is characterised by pai (localised, radiatig ad regioal), which may be associated with systemic symptoms. The iitial bite may oly cause mild discomfort or irritatio, ad sometimes is ot eve oticed. Local pai icreases over a hour or two ad may radiate up the limb. Abdomial or chest pai may develop as may pai at other sites. The pai is of a uusual quality, persistet ad usually severe eough to iterfere with ormal activities (work or sleep). The duratio of effects vary with oly moderate pai for a few hours i some cases to severe persistet pai for 2-5 days. The bite site is ofte red ad the pathogomic fidig is localised diaphoresis (sweatig). A obvious bite mark with swellig, iflammatio, fag marks or bleedig is ucommo. No-specific systemic effects such as ausea, vomitig, headache, malaise ad lethargy are also commo. Rarely, other effects are reported such as eurological maifestatios, fever, hypertesio ad priapism. Red-back spider eveomig is ot life-threateig eve to ifats ad childre. No deaths have bee reported sice the mid-1950s. I most cases, the diagosis is made based o the history of a bite by a red-back spider ad the cliical effects. The type of pai ad the presece of local diaphoresis aloe may be sufficiet to strogly suggest the diagosis eve if a bite is ot cofirmed. The diagosis i childre or ifats who are uable to give a history may be difficult. RED-BACK SPIDER BITE Cliical features ad diagosis Red-back spider bites are ot life-threateig but ca result i severe pai ad systemic symptoms that ca cotiue for hours to days. Bites typically occur whe puttig o shoes left outside, sittig o outdoor furiture, puttig o bike helmets, movig thigs i storerooms or pickig up pot plats or other garde items. Most people are able to idetify redback spiders ad therefore provide a reliable idetificatio if the spider is see bitig. Maagemet First aid There is o defiitive first aid for latrodectism. Cold packs or alteratively heat packs o the bite area sometimes help dimiish pai. A pressure badage will make the pai worse ad is ot recommeded. Further maagemet Red-back spider bite is commo but very ulikely to prove lethal, eve if utreated. Sigificat eveomig occurs i about a third of cases, but these patiets may have several days of distress. Sakebite & Spiderbite Cliical Maagemet Guidelies Third Editio NSW HEALTH PAGE 21

4 Those patiets who preset to hospital with o or miimal symptoms may be allowed home. The patiet should be istructed to seek further medical care should pai or other symptoms develop which require treatmet. Ativeom is sometimes give: if there is a history, symptoms ad sigs cosistet with systemic eveomig, ad severe pai uresposive to oral aalgesics. However, recet trials show ativeom has a low respose rate little better tha placebo, ad ay effect is less tha might be achieved with optimal use of stadard aalgesics. There are o useful or diagostic laboratory tests for redback spider bite. Ativeom treatmet CSL Red Back Spider Ativeom is refied horse IgG F(ab )2, averagig 1.5mL per vial. Admiistratio The preferred route is itraveous (i cotrast to maufacturer s product iformatio which states This medicie is usually ijected ito a muscle, or i lifethreateig cases may be diluted ad give via a vei ). Aaphylaxis to this ativeom is rare. 1. Give 2 vials I.V; dilute the ativeom i 100ml of ormal salie ad admiister over 20mis usig a pump. Always have adrealie ad full resuscitatio available i case of aaphylaxis, but premedicatio is ot required. 2. If icomplete resolutio of symptoms seek expert advice, repeat doses of ativeom are ofte give but there is o good ratioale or evidece to support this ad it is ot recommeded. 3. The dose is the same i adults ad childre. 4. Pregacy or lactatio are ot cotraidicatios to ativeom. Further maagemet advice ca be obtaied through the NSW Poisos Iformatio Cetre ( ). FUNNEL WEB SPIDER BITE Cliical Features ad Diagosis Fuel web spider bite is potetially rapidly lethal. It should be treated as a acute medical emergecy. Specific ativeom is available ad life-savig i cojuctio with supportive care. Expert advice is always available from the NSW Poisos Iformatio Cetre ( ). First aid The first aid for Fuel Web Spider bites is the same as for sake bites. Apply a pressure badage with immobilisatio (PBI). The pressure badage should be a broad (15 cm) elasticised badage, rather tha a crepe badage. The badage is applied over the bite site ad the distally to proximally coverig the whole limb. It should be applied about as tight as that used for a spraied akle. The limb ad whole patiet should be immobilised for the first aid to be effective. The badage ad immobilisatio should remai util the patiet has bee trasferred ad assessed i hospital. The badage should oly be removed if ativeom is available ad after there is o evidece of eveomig based o cliical examiatio. If the patiet is eveomed the badage ca be removed after ativeom has bee admiistered. A cosiderable umber of Fuel Web Spider bites do ot result i sigificat illess, ad do ot require ativeom, but all suspected or cofirmed fuel web spider bites must be observed for at least 4 hours with routie observatios recorded i.e. pulse, blood pressure, respiratory rate ad oxyge saturatio levels as per local protocols. The bite is usually paiful ad fag marks are preset i most cases. If systemic eveomig is preset, urgetly cosider ativeom therapy as this may be lifesavig (see Ativeom Therapy sectio i these guidelies). The cliical features arise directly or idirectly from excessive activity of the autoomic ad peripheral ervous system are summarised below. PAGE 22 NSW HEALTH Sakebite & Spiderbite Cliical Maagemet Guidelies Third Editio

5 Table 4. Summary of the cliical effects of fuel-web spider eveomig CLINICAL SYNDROME Autoomic excitatio icludig choliergic ad catecholamiergic effects Neuromuscular ad sesory excitatio Cardiac effects ad Pulmoary oedema Other severe effects No-specific systemic symptoms CHARACTERISTICS Geeralised diaphoresis ad piloerectio Hypersalivatio, lacrimatio Hypertesio, bradycardia or tachycardia Miosis or mydriasis Fasciculatios local or geeralised; characteristically togue fasciculatio is see Paraesthesia local, distal ad oral Muscle spasms local or geeralised No-cardiogeic/eurogeic pulmoary oedema Myocardial ijury/stuig leadig to Cardiogeic pulmoary oedema (less commo tha o-cardiogeic) hypotesio Drowsiess or coma rare ad typically occurs late or i associatio with severe eveomig Multiorga failure occurs late i life-threateig cases if ativeom has ot bee admiistered Agitatio/axiety Abdomial pai Nausea, vomitig Headache Cliical maagemet of fuel web spider bite Key toxicological priciples for specific treatmet If the patiet arrives without a pressure badage with immobilisatio the apply oe immediately Do ot remove first aid util ready to treat with ativeom Establish itraveous access If there are ay symptoms of systemic eveomig give 2 vials of CSL Fuel Web Spider Ativeom itraveously Be prepared to give more ativeom util major symptoms resolve. Childre require the same dose as adults Seek cosultatio i ay patiet ot respodig to iitial ativeom. Supportive care Respiratory failure is usually due to pulmoary oedema ad may require emergecy resuscitatio ad assisted vetilatio. Itubatio ad PEEP may assist i severe cases. Atropie may be useful if choliergic features are marked ad ativeom is ot immediately available. Severe hypertesio may occur, ad sedatio is the most appropriate first lie treatmet as it will ot exacerbate other features of poisoig. Sakebite & Spiderbite Cliical Maagemet Guidelies Third Editio NSW HEALTH PAGE 23

6 Ativeom admiistratio Ativeom for fuel web spider bite should always be give IV with the patiet ad cliical eviromet appropriately prepared to maage aaphylaxis should it occur. No pre-medicatio is required. Due to the ature of eveomatio by Fuel Web Spiders (i.e. catecholamie storm), aaphylaxis is very ulikely. Other commo spiders that cause miimal effects There are a umber of recogisable groups of spiders that cause miimal effects. Orb-weavig spiders are commo web buildig spiders ad bites cause local pai ad redess ad ofte occur from spiders i clothes left out o the washig lie overight. Hutsma spiders are recogisable large spiders that are commoly foud climbig walls i houses ad are feared by may people. Bites from these spiders cause local pai, local bleedig ad fag marks due to the size of the spider. Wolf spiders are commo groud dwellig spiders ad cause local pai, fag marks redess ad local itchiess i a third of cases. White-tail spiders are commo ad foud i homes i easter ad souther Australia. These spiders do ot cause ecrosis ad bites cause local pai ad redess, ad less commoly a persistet red mark ad associated itchiess. Black house spiders are medium sized spiders foud commoly i the corers of widows ad doors ad have also bee blamed for ecrotic ulcers. Bites by black house spiders cause local pai ad redess. Cliical maagemet of other commo spiders The treatmet of all mior spider bites is reassurace ad symptomatic relief of local effects icludig pai. Tetaus status should be assessed ad updated as required for all spider bites. Necrotic arachidism ad the white-tail spider myth Necrotic arachidism has ever bee cofirmed i Australia although there has bee sigificat misiformatio i the past about bites by white-tail spiders. Bites by loxosceles spiders (Recluse spiders) ca cause cutaeous lesios, but these spiders do ot occur i Australia. There is o evidece that ay Australia spiders ca cause ecrotic ulcers, although white-tail spiders, wolf spiders ad black house spiders have bee blamed for cases of ecrotic ulceratio. Prospective studies of defiite bites by white-tail spiders, black house spiders ad wolf spiders foud that oe of these spiders cause ecrotic lesios. There are umerous reports of cases of misdiagosed spider bites where a alterate diagosis has bee foud, icludig dermatophytoses, squamous cell carcioma, staphylococcal ifectios, pyoderma gagreosum, cutaeous polyarteritis odosa, uusual ifectios ad diabetic ulcers. The appropriate ivestigatio of ski lesios attributed to spider bites is icluded i Table 5. There are a umber of large black spiders that commoly get mistake for fuel-web spiders. Trapdoor spiders look very similar to fuel-web spiders but bites oly cause local pai ad fag marks. Mouse spiders are aother big black spider easily mistake for fuel-web spiders. All bites by these spiders should be iitially treated as a suspected fuel-web spider bite. PAGE 24 NSW HEALTH Sakebite & Spiderbite Cliical Maagemet Guidelies Third Editio

7 Table 5. A approach to the ivestigatio ad diagosis of ecrotic ski ulcers, presetig as a suspected spider bite 1. Establish whether or ot there is a history of spider bite IF a clear history of a spider bite (best if spider is caught) Refer to iformatio o defiite spider bites IF NO history of spider bite Ivestigatio should focus o the ulcer ad the provisioal diagosis of a suspected spider bite is ot appropriate. 2. Cliical history ad examiatio Focus o features suggestive of ifectio, maligat processes or vasculitis. Cosider uderlyig disease processes: diabetes, vascular disease Evirometal exposure: soil, chemical, ifective Prescriptio medicatios History of mior trauma Specific historical iformatio about the ulcer (may assist i differetiatig some coditios): Paiful or pailess Duratio ad time of progressio Precedig lesio 3. Ivestigatio Ski biopsy: Microbiology (with appropriate trasport media): cotact microbiology laboratory prior to collectig specimes so that appropriate material ad trasport coditios are used for orgaisms such as Mycobacterium spp., fugi ad uusual bacterial. Histopathology Laboratory: other supportive ivestigatios may be importat for uderlyig coditios (autoimmue coditios, vasculitis ad pyoderma gagreosum). These may iclude, but ot be limited to: full blood cout coagulatio studies biochemistry (icludig liver ad real fuctio tests) autoimmue screeig tests cryoglobulis chest radiography colooscopy vascular fuctio studies of lower limbs 4. Treatmet Local woud maagemet Appropriate treatmet based o established pathology. Ivestigatio ad treatmet of uderlyig coditios may be importat, (pyoderma gagreosum or a systemic illess such as diabetes) 5. Follow up ad moitorig Diagosis: may take weeks or moths to become clear. Essetial that these patiets are followed Cotiuig maagemet: coordiated with multiple specialities ivolved Source: From Isbister GK ad Whyte IM, 2004, Suspected white-tail spider bite ad ecrotic ulcers, Iteral Medicie Joural Volume 34, Issue 1-2, 38 44, Jauary 2004 Sakebite & Spiderbite Cliical Maagemet Guidelies Third Editio NSW HEALTH PAGE 25