There are important differences between blood transfusions

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1 Revised My CE Credit Idiosyncrsies in Feline Blood Trnsfusions DeeDee Schumcher, CVT, VTS (ECC), MEd Des Moines Are Community College Ankeny, Iow There re importnt differences between blood trnsfusions in dogs nd cts. Although not s common s cnine trnsfusions, feline trnsfusions re becoming more common. Newly discovered feline red blood cell (RBC) ntigens nd improved dignostic tests for determining feline blood types re helping improve the prcticlity nd sfety of feline trnsfusion medicine. 1 Feline Blood Types Hving bsic understnding of feline blood types cn help with feline blood trnsfusion nd blood bnking. Feline blood types re clssified ccording to n AB blood group system: cts hve type A, B, or AB blood. This blood-typing system is not relted to the humn ABO blood-typing system. Most cts in the United Sttes hve type A blood, but this cn vry slightly by region. Domestic shorthired cts re slightly more likely to hve type B blood in the South nd on the West Cost thn in the Northwest or Northest. 2 In ddition, certin feline breeds, including the British shorthir, Cornish rex, sphinx, nd Persin, re more likely thn other breeds to hve type B blood. 3 Cts with type AB blood re extremely rre. Cts hve nturlly occurring llontibodies in their blood. This mens tht cts re born with ntibodies on the surfce of their blood cells tht recognize ntigens from other feline blood types s foreign. Cts with type B blood hve very strong nti A llontibodies, nd cts with type A blood hve wek nti B llontibodies. Although cts with type AB blood theoreticlly do not hve llontibodies, it is recommended tht these cts receive type A blood to prevent minor incomptibility rections. 4 Therefore, cts, unlike dogs, do not hve universl blood type. This is one reson why feline blood is not commonly found in locl niml blood bnks. It would be very costly nd lbor intensive for locl niml blood bnks to stock ll types of feline blood. It is importnt to remember tht ftl neontl hemolytic rections cn occur in kittens if they re born with different blood type thn the queen. For exmple, if tom with type A or type AB blood breeds with queen with type B blood, the kittens my hve type A or type AB blood. In utero, the plcent protects the fetuses from the queen s strong nti A ntibodies. However, fter birth, when the kittens receive colostrum contining protective ntibodies from the queen during nursing, they lso receive the queen s strong nti A ntibodies. This cuses the kittens to develop severe nd often life-thretening hemolytic rection known s neontl isoerythrolysis. The kitten s immune system begins to recognize its own blood cells s foreign nd destroys them. This cn be prevented by blood typing cts before mting nd not llowing toms with type A blood to breed with queens with type B blood. Theoreticlly, becuse dogs do not hve nturlly occurring llontibodies, when they receive n initil blood trnsfusion (whtever the blood type), they should not hve trnsfusion rection (but blood typing nd crossmtching re still recommended in dogs). However, cts must lwys receive type-specific blood becuse of their llontibodies, even during n initil trnsfusion. If ct receives s little s 5 ml of n incomptible type of blood, n cute, life-thretening trnsfusion rection my occur. 2 Feline Blood Typing Commercil, in-house feline blood-typing kits (RpidVet-H IC, DMS Lbortories; Quick Test A+B, Alvedi) re reltively inexpensive, quick, nd effective for screening types A nd B blood when blood typing results re needed immeditely. However, these tests sometimes hve difficulty differentiting between Key Points types B nd AB blood. 4 Although off-site tests (modified gel nd tube tests) tke longer nd re slightly more expensive, they re still considered the gold stndrd for feline blood typing nd should be used for conclusive blood typing of breeding queens nd blood donors. Anti-Mik Allontibody It hs been demonstrted through crossmtching nd Cts must lwys receive typespecific blood becuse of their llontibodies, even when receiving trnsfusion for the first time. To prevent ftl hemolytic rection, it is impertive to crossmtch ll feline blood products (even those tht re type specific) with the recipient s blood before ech trnsfusion. Component therpy is the preferred trnsfusion method in cts. E1 Copyright 2012 Vetstreet Inc. This document is for internl purposes only. Reprinting or posting on n externl website without written permission from Vetlern is violtion of copyright lws.

2 Idiosyncrsies in Feline Blood Trnsfusions Box 1. Slide Crossmtch,8 Mjor crossmtch: Plce 2 drops of the recipient s plsm nd 1 drop of the donor s EDTA-nticogulted whole blood on glss slide, gently invert (mix) for 1 min, nd observe for gglutintion. Minor crossmtch: Plce 2 drops of the donor s plsm nd 1 drop of the recipient s EDTA-nticogulted whole blood on glss slide, gently invert (mix) for 1 min, nd observe for gglutintion. If gglutintion is observed on either test, new donor should be selected. Use this method only in emergencies becuse it might produce flse-negtive results. EDTA = ethylenediminetetrcetic cid. hemolytic rections tht blood incomptibilities cn occur even when feline blood trnsfusions re type specific. 1 These blood incomptibilities led to the discovery of common RBC ntigen clled Mik in domestic shorthired cts. 5 Approximtely 94% of domestic shorthired cts tht re tested hve the Mik ntigen. 1 Although the nturlly occurring nti-mik llontibody is rre, its discovery my led to the discovery of new feline blood types or even more specific feline blood-typing system. (PennGen Lbortories t the University of Pennsylvni [Phildelphi] offers the Mik blood type test. 6 ) For now, to prevent ftl hemolytic rections, it is impertive to crossmtch ll feline blood products (even those tht re type specific) with the recipient s blood before trnsfusion. Crossmtching Crossmtching tests for incomptibilities due to dditionl ntibodies in the blood of recipients nd donors. A crossmtch cn be mjor or minor. A mjor crossmtch tests for ntibodies ginst donor cells in recipient s plsm. A minor crossmtch tests for ntibodies ginst the recipient s cells in the donor s plsm. The mjor crossmtch is more importnt thn the minor crossmtch becuse the former predicts the gretest likelihood of mjor hemolytic rection due to trnsfusion. If the blood from either crossmtch is found to be incomptible, different donor should be used. If ct will receive second trnsfusion from the sme donor, the second blood product should lso be crossmtched with the recipient. After trnsfusion, it my tke s few s 4 dys for llontibodies to be present, but they cn lst for yers fter blood trnsfusion. 7 Therefore, incomptibility rections re not prevented by using the sme donor for recipient. BOX 1 8 describes the slide crossmtch method, nd BOX 2 9 describes the blood crossmtch method. Feline Blood Dontion Even if you re fortunte enough to hve locl niml blood bnk in your re, feline blood products my not be vilble. However, they cn be purchsed from lrge commercil blood bnks (i.e., Animl Blood Resources Interntionl, Dixon, Cliforni, or ACCES Blood Bnk Settle, Wshington; BOX 3). Alterntively, feline blood products cn be obtined in-house from clinic cts or volunteer donors. Box 2. Blood Crossmtch 9 1. Collect 1 ml of the recipient s blood, plce it in n EDTA tube, nd lbel it Recipient s blood. 2. Collect 1 ml of the donor s blood from the pigtil on the bg of blood nd plce it into red-top tube. Alterntively, drw 1 ml of blood directly from the donor, plce it into n EDTA tube, nd lbel it Donor s blood. 3. Centrifuge ech tube for 10 min t 3000 rpm. 4. Remove nd sve the plsm from ech tube nd lbel them Donor s plsm nd Recipient s plsm. 5. Wsh the donor s RBCs by dding 5 ml of 0.9% sline to 0.2 ml of the donor s RBCs. In seprte tube, dd 5 ml of 0.9% sline to the recipient s RBCs. Centrifuge these tubes for 1 min nd remove the superntnt. 6. Repet step 5 three times. 7. Lbel three tubes Mjor crossmtch, Minor crossmtch, nd Recipient s control. 8. Add 2 drops of plsm nd 2 drops of RBCs to ech tube s follows: Mjor crossmtch 2 drops of the recipient s plsm nd 2 drops of the donor s RBCs Minor crossmtch 2 drops of the donor s plsm nd 2 drops of the recipient s RBCs Recipient control 2 drops of the recipient s plsm nd 2 drops of the recipient s RBCs 9. Let the tubes sit for min, nd then centrifuge them t 3000 rpm for 15 sec. 10. Observe for hemolysis. 11. Gently invert the tubes to resuspend the precipitte. 12. Add 1 drop from ech tube to correspondingly lbeled slide, nd exmine for microscopic gglutintion. Suspect immune-medited hemolytic disese if the recipient s control smple demonstrtes hemolysis or gglutintion. Select new donor if hemolysis or gglutintion is observed in the mjor or minor crossmtch smples. EDTA = ethylenediminetetrcetic cid. The generl guidelines for feline blood donors re s follows: No history of blood trnsfusion Adult (2 to 8 yers of ge) Good ntured Indoor only Helthy Weigh t lest 8.8 lb (4 kg) Test negtive for FeLV nd FIV Current on ll core vccintions Binnul complete blood counts, blood chemistry pnels, fecl prsite exmintions, nd physicl exmintions Other tests for infectious disese (e.g., infection with Mycoplsm hemofelis, Cytuxzoon felis, or Bbesi spp) my be recommended bsed on the region of the country Regulr fle nd tick preventives A pcked cell volume (PCV) of t lest 30%; 35% is idel 5 E2

3 Idiosyncrsies in Feline Blood Trnsfusions Box 3. Ntionl Commercil Animl Blood Bnks ACCES Blood Bnk Settle, Wshington Phone: Animl Blood Resources Interntionl Dixon, Cliforni; Stockbridge, Michign Phone: Estern Veterinry Blood Bnk Purcellville, Virgini Phone: HEMOPET Grden Grove, Cliforni Phone: Penn Animl Blood Bnk Phildelphi, Pennsylvni Phone: SpeciltyCreServices/BloodBnk/tbid/432/Defult.spx This is not comprehensive list. Feline Blood Collection Feline blood collection vries gretly from cnine blood collection. Unlike dogs, most feline donors re sedted before blood dontion, which dds some risk to the procedure. Becuse most ct owners re hesitnt to hve their cts sedted to donte blood, it is often difficult for locl niml blood bnks to find enough feline blood donors to meet the demnd for ech blood type. Lrge niml blood bnks usully hve in-house ct colonies to provide dequte quntities of type-specific blood. Feline blood cn be collected using closed system or n open system. In either cse, the donor ct is often sedted; mny experts recommend using ketmine (20 mg/ct IM) 8 or n IM combintion of ketmine (5 to 6 mg/kg) nd dizepm or midzolm (0.5 mg/ ct). 9 The jugulr vein re is clipped nd septiclly prepred. Mny experts recommend giving feline donors 0.9% sline (~90 ml SC) fter blood collection to help mintin homeostsis nd hydrtion. 2 (In ddition, I recommend giving feline blood donors lots of ffection fter the trnsfusion.) The open collection system usully consists of 19-guge butterfly ctheter nd 60-mL syringe contining 7 ml of citrte phosphte dextrose denine (CPDA-1). Approximtely 53 ml of blood cn be septiclly collected from feline donor s jugulr vein over 10-minute period. 10 Drwing blood too quickly cn cuse n unsfe drop in blood pressure. Becuse the open collection system llows contct between the blood nd the environment (room ir), the blood Figure 1. A smll niml, double-bg, syringe collection set. (Courtesy of Animl Blood Resources Interntionl) should be used immeditely or refrigerted for no longer thn 24 hours to prevent potentil bcteril contmintion. 10 Becuse of its simplicity nd convenience, the open collection system is used most often in cts. However, becuse blood collected this wy cnnot be stored for more thn 24 hours, component therpy ws not possible in cts until closed collection system ws creted. Using closed system is preferred for feline blood collection becuse it decreses the risk of contmintion nd llows blood to be seprted into its components nd stored for longer periods of time. Penn Animl Blood Bnk nd Tufts University hve both developed closed collection systems for cts. Animl Blood Resources Interntionl sells closed collection system for cts (FIGURE 1). Becuse closed collection system does not expose the blood to the environment or room ir, the collected blood cn be stored for up to 35 dys (if CPDA-1 is used) or centrifuged into components. 2 Once the blood hs been centrifuged, pcked RBCs cn be refrigerted for 21 dys nd fresh frozen plsm (FFP) cn be frozen for 1 yer if CPDA-1 is used. 1 Seprting blood into its components requires specil equipment nd expertise. If this is not performed properly, the storge life of blood products cn be substntilly shortened. Component Therpy As in dogs, component therpy is the preferred trnsfusion method in cts. Component therpy involves centrifuging whole blood into its components (pcked RBCs nd plsm) nd trnsfusing only wht the recipient needs. Becuse ny blood component cn cuse trnsfusion rection, only trnsfusing wht is needed reduces the risk. Although component therpy is less common in cts, it is much sfer option for them. Blood Product Administrtion All blood products should be dministered through n IV ctheter nd IV set seprte from those for dministering other fluids nd medictions. 7 Refrigerted blood should be wrmed to room temperture before trnsfusion. The temperture should not exceed E3

4 Idiosyncrsies in Feline Blood Trnsfusions Glossry Allontibody An ntibody produced by one individul tht rects with llontigens of nother individul of the sme species Allontigen An ntigen tht exists in lterntive forms in species, thus inducing n immune response when one form is trnsferred to members of the species tht lck it Component therpy Centrifuging whole blood into its individul elements (i.e., pcked red blood cells nd fresh frozen plsm) nd only trnsfusing the components tht the recipient needs Crossmtching Testing for incomptibles due to llontibodies in the recipient s nd the donor s blood Fresh frozen plsm A blood component tht is frozen immeditely fter it is seprted from whole blood Hemoglobinemi Excess hemoglobin in the blood s result of intrvsculr hemolysis Hemoglobinuri Excess hemoglobin in the urine s result of intrvsculr hemolysis Mik A red blood cell ntigen in domestic shorthired cts Neontl isoerythrolysis A condition in which newborn hs hemolytic rection to its own blood due to ntibodies it received from its mother (of nother blood type) during nursing Pcked red blood cells A blood component tht consists of concentrted red blood cells seprted from plsm Urticri Hives Blood DC, Studdert VP, Gy CC. Sunders Comprehensive Veterinry Dictionry. 3rd ed. Toronto, Cnd: Sunders Elsevier; 2007: F (37 C) or the cells my be dmged. 2 Blood collected using n open system should be filtered through 20-µm syringe blood filter (i.e., Hemo-Nte [Uth Medicl Products] or Kogente filter [Byer HelthCre]). If closed collection system is used or single component is dministered, the blood product should be dministered using feline blood dministrtion set. The recipient should be monitored immeditely before the trnsfusion so tht bseline vitl signs cn be obtined. The volume of blood or blood product to dminister vries depending on the donor s nd the recipient s PCVs, the reson for the trnsfusion, nd the condition of the recipient. Generlly, when whole blood is trnsfused, the recipient s PCV cn be expected to increse by 1% if 3 ml/kg of blood is trnsfused. 11 In cts, plsm is generlly trnsfused t dose of 10 ml/kg. 11 Trnsfusion Rections A trnsfusion should be very slow (0.25 ml/kg/h 2 ) for the first 15 minutes to llow erly detection of n cute trnsfusion rection, including fever, urticri, vomiting, or dirrhe. If ny of these signs re observed, the trnsfusion should be stopped nd the rection treted immeditely. Fever cn be treted with n ntipyretic (e.g., metmizole t 20 mg/kg slow IV). 11 Antihistminergic drugs (e.g., diphenhydrmine HCl t 2 mg/kg IV) cn be used to tret urticri. 12 Antiemetics (e.g., chlorpromzine HCl t 0.5 mg/kg IV, IM, or SC) cn be used to tret vomiting. 12 If the trnsfusion rection is mild nd there re no signs of severe, life-thretening hemolytic rection (e.g., hemoglobinemi, hemoglobinuri, intrvsculr hemolysis), the trnsfusion my be continued t slower dministrtion rte while the recipient is continuously monitored for signs of trnsfusion rection. However, if the trnsfusion rection ws severe, dministrtion of the blood product cnnot be resumed. Severe trnsfusion rections tht cuse shock should be treted using IV fluid therpy nd glucocorticoids (e.g., prednisolone sodium succinte t 50 to 100 mg IV 11 ) s for ny other type of nphylxis. If no signs of n cute trnsfusion rection re observed within the first 15 minutes, the rte of dministrtion cn be incresed to s high s 22 ml/kg/h. 2 The entire trnsfusion should tke no longer thn 4 hours. 4 Throughout the trnsfusion, the recipient should be crefully monitored for signs of rection. No specil ftercre is recommended for the donor. Conclusion Blood trnsfusion is very different in dogs nd cts. Knowledge of the idiosyncrsies of feline trnsfusion medicine is incresing with continued reserch, the findings of which hve improved the prcticlity nd sfety of blood trnsfusions in feline ptients. References 1. Weinstein NM, Blis MC, Hrris K, et l. A newly recognized blood group in domestic shorthir cts: the Mik red cell ntigen. J Vet Intern Med 2007;21(2): Mthews KA. Veterinry Emergency nd Criticl Cre Mnul. Ontrio, Cnd: Lifelern Publishers; Blood groups nd blood trnsfusions: introduction. The Merck Veterinry Mnul Web site. Accessed Februry 22, Giger U. Trnsfusion medicine. In: Silverstein D, Hopper K, eds. Smll Animl Criticl Cre Medicine. St Louis, MO: Elsevier; 2008: Stieger K, Plos H, Giger U. Comprison of vrious blood-typing methods for feline AB blood group system. Am J Vet Res 2005;66(8): University of Pennsylvni School of Veterinry Medicine. Blood tests nd typing. PennGen Web site /Defult.spx. Accessed Februry 22, Giger U. Therpeutic considertions for the bleeding dog. Proc IVECCS Vp LM. An updte on blood typing, crossmtching, nd doing no hrm in trnsfusing dogs nd cts. dvm360 Web site. rticledetil.jsp?id= Published October 1, Accessed Februry 22, Jck CM, Wtson PM. Veterinry Technicin s Dily Reference Guide. 2nd ed. Ames, IA: Wiley-Blckwell; Trnsfusion medicine. In: Wingfeld WE, Rffe MR, eds. The Veterinry ICU Book. Jckson Hole, WY: Teton New Medi; 2002: Kohn B, Weingrt C. Feline blood typing nd trnsfusion: prcticl pproch. Proc WSAVA Plumb DC. Plumb s Veterinry Drug Hndbook. 6th ed. Ames, IA: Wiley-Blckwell; E4

5 Idiosyncrsies in Feline Blood Trnsfusions 1 CE Credit The rticle you hve red qulifies for 1.0 credit hour. To receive credit from Alfred Stte College, choose the best nswer to ech of the following questions. CE tests must be tken online t Vetlern.com; test results nd CE certifictes re vilble immeditely. 1. Which blood type is most common in cts in the United Sttes?. the universl feline blood type b. type A c. type B d. type AB 2. Neontl isoerythrolysis cn be prevented by. blood typing ll cts fter breeding. b. not breeding toms with type B blood to queens with type A blood. c. not breeding toms with type A blood to queens with type B blood. d. ensuring tht ll kittens receive colostrum from their mother. 3. If s little s ml of n incomptible type of blood is given to ct, severe, life-thretening rection cn occur.. 1 b. >1 c. 3 d ntigen is n RBC ntigen found in ~94% of domestic shorthired cts in the United Sttes.. A b. B c. DSH d. Mik 5. Crossmtching tests for. incomptibilities due to dditionl ntibodies in the recipient s nd the donor s blood. b. ll feline blood types. c. incomptibilities due to mjor ntibodies in the recipient s blood. d. incomptibilities due to minor ntibodies in the recipient s blood. 6. Incomptibility rections cn be prevented by. blood typing the recipient nd the donor. b. blood typing nd crossmtching the recipient nd the donor. c. lwys using the sme donor. d. never using the sme donor. 7. Feline blood donors should hve PCV of t lest. 20%. b. 25% c. 30%. d. 45%. 8. Blood collected using n open collection system. is often seprted into pcked RBCs nd plsm. b. should be used within 24 hours. c. is not convenient for component therpy. d. b nd c 9. Component therpy is preferred becuse. it is less expensive for clients. b. it is sfer for ptients. c. whole blood trnsfusions re dngerous. d. none of the bove 10. Whole blood cn be seprted into. FFP nd pcked RBCs. b. FFP only. c. pcked RBCs only. d. none of the bove E5 Copyright 2012 Vetstreet Inc. This document is for internl purposes only. Reprinting or posting on n externl website without written permission from Vetlern is violtion of copyright lws.