Methylene blue ya amphaka: chitetezo, zotsatira zosafunika, ndi malangizo a dokotala wa zinyama

Mphaka akumwa madzi a mu thanki ya nsomba yomwe yangothiridwa mankhwala othana ndi bowa. Mwini mphaka akuwerenga pa intaneti kuti methylene blue inathandiza galu amene anali ndi vuto la magazi, ndipo akudzifunsa ngati ingathandizenso mphaka. Zochitika ziwirizi zimaoneka zofanana tikaziyang'ana kuchokera kunja. Koma mkati mwa thupi la mphaka, sizili choncho.

Amphaka ali pachiwopsezo chachikulu cha kuwonongeka kwamtundu umodzi chifukwa cha methylene blue: kuwonongeka kwa maselo ofiira a magazi chifukwa cha okosideshoni. Chiwopsezochi chimachokera ku kapangidwe ka hemoglobin ya amphaka, ndipo n'chifukwa chake malangizo okhudza amphaka ayenera kukhala apadera. Malangizo olembedwa a nsomba za mu thanki, a agalu, kapena a utoto wopatsira zitsanzo za ku labotale sangogwiritsidwa ntchito kwa amphaka. Nkhaniyi ikufotokoza mmene thupi limagwirira ntchito, zimene mabuku a zamankhwala a zinyama amanena, ndi zochita mphaka akakumana ndi mankhwalawa.

Maselo ofiira a magazi a amphaka ali ndi kapangidwe kosiyana

Hemoglobin imanyamula okosijeni, koma kapangidwe kake kamatsimikizanso mmene imawonongekera mosavuta ndi zinthu zoyambitsa okosideshoni. Hemoglobin ya amphaka ili ndi magulu pafupifupi asanu ndi atatu a sulfhydryl omwe amalowa mosavuta m'machitidwe a makemikolo pa tetramer iliyonse, pafupifupi kuwirikiza chiwerengero chopezeka mwa agalu kapena anthu. Magulu amenewa ndiwo amakhudzidwa ndi okosideshoni. Akachitika okosideshoni, maunyolo a globin amataya kapangidwe kawo n'kuunjikana kukhala tinthu takuda totchedwa tinthu ta Heinz, tomwe timaoneka mu zopaka magazi zopatsidwa utoto.

Zinthu zina ziwiri zimakulitsa vutoli mwa amphaka. Choyamba, maselo ofiira a magazi a amphaka ali ndi mphamvu zochepa poyerekezera ndi nyama zina zolimbana ndi okosideshoni ndi kusintha zinthu zobwera chifukwa chake, choncho kuwonongeka kukangoyamba kumapitirira kwambiri. Chachiwiri, ndulu ya mphaka siigwira bwino ntchito yochotsa tinthu ta Heinz m’maselo ofiira a magazi popanda kuwononga selolo. Nyama zina zimachita bwino ntchito yoyeretsayi, monga tafotokozera mu ndemanga iyi ya sayansi ya magazi a amphaka. Choncho maselo owonongekawo amapitiriza kuyenda m’magazi m’malo mokonzedwa.

Amphaka athanzi angakhale ndi tinthu tochepa ta Heinz popanda kudwala. Kutengera buku logwiritsidwa ntchito ndi njira yopatsira utoto, kupezeka kwa tinthu ta Heinz m’maselo ofiira a magazi okwana pafupifupi asanu mpaka khumi pa zana kungakhale kosadetsa nkhawa. Nkhawa imayamba tinthuto tikakhala tambiri kapena tikulu: buku lina la zamankhwala a ku labotale limati kuchepa kwa magazi kumakhala kotheka tinthu ta Heinz tikulu tikakhudza maselo ofiira a magazi oposa makumi atatu pa zana. Malirewa afotokozedwa mwachidule mu chiyambi ichi cha kuchepa kwa magazi chifukwa cha tinthu ta Heinz. Choncho mphaka akakumana ndi mankhwalawa, funso silikhala kungoti kodi tinthu ta Heinz tilipo. Limakhala lakuti ndi tingati, ndi tikulu motani, ndipo kodi maselo ofiira a magazi akuwonongeka pambuyo pake.

Zimene mabuku a zamankhwala a zinyama amanena

Buku lakale la Plumb's Veterinary Drug Handbook limanena kuti madokotala ambiri amaona methylene blue ngati mankhwala amene sayenera kugwiritsidwa ntchito kwa amphaka, chifukwa amphaka angakhale ndi kuchepa kwa magazi chifukwa cha tinthu ta Heinz komanso methemoglobinemia. Nkhawa zimene limatchula ndi kusintha kwa maonekedwe a maselo ofiira a magazi, methemoglobinemia yoyambitsidwa ndi mankhwala amene akuyenera kuichepetsa, ndi kufupika kwa moyo wa maselo ofiira a magazi. Komabe, gawo lomwelo limapereka mlingo wa mwadzidzidzi wa amphaka a methemoglobinemia, nthawi zambiri 1 mpaka 1.5 mg pa kg kudzera mumtsempha monga chithandizo cha kamodzi. Kuphatikizana kumeneku kumasonyeza tanthauzo lenileni: kunena kuti sayenera kugwiritsidwa ntchito pano kumatanthauza kuwapewa kupatula pa zochitika zochepa zoyang'aniridwa ndi dokotala, osati kuti saperekedwa konse. Mawu a gawo lakalelo opezeka kwa anthu ali mu kopi iyi ya buku la Plumb's, pamene buku la khumi lomwe likugwiritsidwa ntchito panopa lili ndi gawolo pa tsamba 859.

Merck Veterinary Manual ilinso ndi maganizo ofanana mu malangizo ake ochizira kuvulala chifukwa cha poizoni wa mankhwala ochepetsa ululu. Imatchula methylene blue pa 1 mpaka 1.5 mg pa kg ya madzi a mankhwala a mlingo wa chimodzi pa zana, yoperekedwa kudzera mumtsempha ngati njira yochepetsera methemoglobin, ndipo imafuna kuyang'anira methemoglobinemia, kuchepa kwa magazi chifukwa cha tinthu ta Heinz, ndi kuwonongeka kwa maselo ofiira a magazi. Merck imanenanso paokha mu chiyambi chake cha kuchepa kwa magazi mwa nyama kuti tinthu ta Heinz timapangika mosavuta mwa amphaka kuposa nyama zina.

Mawu amphamvu kwambiri a malamulo okhudza mankhwalawa akunena za zinthu zoperekedwa pakamwa. Lamulo la boma la feduro la 21 CFR gawo 500.27 limalemba kuti mankhwala awiri akumwa opha tizilombo m’njira ya mkodzo, omwe anali ndi methylene blue, anayambitsa kuchepa kwa magazi chifukwa cha tinthu ta Heinz ndi kuwonongeka kwa maselo ofiira a magazi mwa amphaka akagwiritsidwa ntchito potsatira malangizo a pa lebulo. Nthawi zina zimenezi zinapha amphakawo, ndipo methylene blue inadziwika kuti ndiyo inayambitsa vutoli. Lamuloli limatsimikiza kuti mankhwala amtundu umenewo a zinyama, okhala ndi methylene blue ndipo operekedwa pakamwa, sanali otetezeka kapena ovomerezedwa kuti amagwira ntchito popanda pempho lovomerezeka. Agalu anapezekanso ndi kuwonongeka kwamtundu womwewo poyesera, choncho mankhwalawa si opanda chiwopsezo kwa agalu. Koma chiwopsezo cha mlingo wolembedwa pa lebulo chinasonyezedwa koyamba mwa amphaka.

Zotsatira zosafunika zimene zanenedwa mwa amphaka zimakhudza kwambiri magazi: kupangika kwa tinthu ta Heinz, kuchepa kwa magazi chifukwa cha kuwonongeka kwa maselo ofiira a magazi, ndi methemoglobinemia yoyambitsidwa ndi mankhwalawo akaperekedwa kwambiri kapena mobwerezabwereza. Mabuku a mankhwala ambiri amatchulanso nseru ndi kusanza, koma umboni wokhudza amphaka mwapadera ndi wa magazi, ndipo n’kumeneko komwe kuyang'anira kuyenera kulunjika.

Chodabwitsa: chithandizo ndi poizoni mu molekyulu imodzi

Mkati mwa selo lofiira la magazi, methylene blue ingasinthidwe kudzera m’njira ya reduction kukhala leucomethylene blue, yomwe imapereka ma elekitironi ku iron ya haem yomwe yachita okosideshoni, n’kubwezeretsa hemoglobin yogwira ntchito. Amenewa ndi machitidwe a makemikolo othandiza pochiza methemoglobinemia, ndipo afotokozedwa mwatsatanetsatane m’nkhani yofotokoza methemoglobinemia. Koma methylene blue yeniyeniyo ndi chinthu choyambitsa okosideshoni. Kuchuluka kwa mankhwalawa kukakwera kapena njira za selo zochita reduction zikalephera kupirira, molekyulu yomweyi imawonjezera methemoglobin ndi kuwonongeka kwa globin m’malo mokonza vutolo. Choncho methemoglobinemia ndi chifukwa choperekera mankhwalawa komanso zotsatira zawo zosafunika. Kusiyana pakati pa ziwirizi ndi kochepa, ndipo kumakhala kochepa kwambiri mwa amphaka.

Umboni womveka kwambiri mwa amphaka umachokera ku kafukufuku wolamulidwa wa 1992 wa amphaka akuluakulu makumi anayi. Mlingo umodzi wa 1.5 mg pa kg woperekedwa kudzera mumtsempha unathetsa mwamsanga methemoglobinemia yoyambitsidwa ndi nitrite popanda kuwonjezera maselo okhala ndi tinthu ta Heinz amene amayenda m’magazi. Kupereka milingo iwiri yotereyo motalikirana ndi maola anayi kunawonjezera kwambiri kupezeka kwa tinthu ta Heinz, makamaka pambuyo pokumana ndi nitrite, ngakhale kuti kuchepa kwa magazi koonekeratu chifukwa cha kuwonongeka kwa maselo ofiira sikunachitike m’nthawi ya kafukufukuyo (Rumbeiha ndi Oehme, 1992). Mlingo umodzi unathandiza. Kubwereza mlingo pasanathe maola ambiri kunasunthira zinthu ku mbali ya kuwonongeka.

Malipoti a zochitika za kuchipatala akusonyezanso zimenezi. Ndemanga ya 2019 mu Journal of Veterinary Internal Medicine imafotokoza methylene blue yoperekedwa kudzera mumtsempha ngati chithandizo choyamba cha methemoglobinemia yoyamba mwadzidzidzi yokhala ndi zizindikiro. Imatchula kugwiritsa ntchito kwa amphaka pa 1 mg pa kg kudzera mumtsempha, ndipo imachenjeza kuti mphaka amene ali kale ndi methemoglobinemia kapena kuchepa kwa magazi chifukwa cha tinthu ta Heinz angawonongeke kwambiri chifukwa cha okosideshoni. Imalimbikitsa kuyeza hematocrit kwa masiku angapo pambuyo pake (DOI 10.1111/jvim.15637). Lipoti lofalitsidwa la mwana wa mphaka amene ankaganiziridwa kuti ali ndi methemoglobinemia yokhudzana ndi madzi akumwa linasonyeza kuti anachira mkati mwa mphindi zochepa atapatsidwa 1 mg pa kg ya madzi a mankhwala a mlingo wa chimodzi pa zana kudzera mumtsempha, ndipo anayezedwa mobwerezabwereza ndi co-oximetry ali m’chipatala (lipoti la chochitikacho). Pa chochitika cha mwadzidzidzi cha 2023, mphaka wa mtundu wa Ragdoll wa miyezi isanu ndi umodzi yemwe anali ndi methemoglobinemia yoopsa yobwerezabwereza anathandizidwa poyamba ndi mankhwala a mumtsempha, kenako ndi mankhwala a pakamwa operekedwa mosamala kwa nthawi yokonzedwa. Mphakayo anachira ndipo panalibe zotsatira zosafunika zazikulu zokhudzana ndi chithandizochi (DOI 10.1111/vec.13298). Kupambana kulikonse kunali pa chochitika chapadera choyang'aniridwa ndi kuyezedwa, osati chitsanzo chololeza kugwiritsa ntchito kunyumba.

Zolemba zakale za poizoni zimasonyeza mbali inayo. Pa zochitika zofufuzidwa mu 1973, amphaka asanu ndi mmodzi anapezeka ndi kuchepa kwa magazi chifukwa cha tinthu ta Heinz ndi kuwonongeka kwa maselo ofiira a magazi atamwa mankhwala a njira ya mkodzo okhala ndi methylene blue. Amphaka ena awiri opatsidwa kuchuluka kofanana poyesera anapezeka ndi kuwonongeka koopsa kwa maselo ofiira a magazi mkati mwa masiku ochepa ndipo anafunika kuikidwa magazi (Schechter ndi anzake, 1973). Pa chochitika chopha mphaka cha 2016, mphaka wachinyamata wosakaniza mtundu wa Angora amene ankalandira mankhwala a matenda a njira ya mkodzo anali ndi kusanduka kwabuluu koonekeratu kwa minyewa ya m’kati ndi ziwalo za thupi, komanso kuwonongeka kwa chiwindi ndi impso. Mbiri yake ndi kufufuza kuwonongeka kwa thupi zinatsimikizira kuti anali ndi poizoni wa methylene blue (lipoti la chochitikacho). Malipotiwa sangathe kupereka malire odalirika a mlingo woyambitsa poizoni pa kukumana ndi mankhwalawa pakamwa, mumtsempha, pakhungu, kapena m’madzi a thanki ya nsomba amene achepetsedwa mphamvu, ndipo nkhaniyi sipereka malire oterowo.

Kuyerekezera kumodzi kuyenera kukonzedwa. Acetaminophen imadziwika kuti ndi yoopsa kwa amphaka chifukwa alibe ma enzyme ofunika a glucuronidation, ndipo olemba ena amagwiritsa ntchito kufotokoza kumeneku pa methylene blue. Kugwiritsa ntchito kufotokoza komweko kulibe umboni. Kulephera kuchita bwino glucuronidation ndi njira yotsimikizika ya kuopsa kwa acetaminophen, yofotokozedwa mu kafukufuku uyu wa mmene matupi a amphaka amasinthira mankhwala. Pa methylene blue, magwero a zamankhwala a zinyama amatsindika machitidwe ake enieni a redox komanso mmene maselo ofiira a magazi a amphaka amawonongekera mosavuta, ndipo FDA imati njira yeniyeni yoyambitsa kuwonongeka kwa tinthu ta Heinz sinatsimikizidwe mokwanira. Zimene zimachitika ndi acetaminophen ndi chikumbutso chothandiza chakuti amphaka amasintha mankhwala m’matupi awo mosiyana. Koma si kufotokoza kwa mankhwala amenewa.

Mphaka akakumana ndi mankhwalawa: mafunso ofunsidwa kawirikawiri

Mphaka wanga wamwa madzi a mu thanki ya nsomba othiridwa methylene blue. Kodi wapeza poizoni?

Sikuti nthawi zonse, ndipo palibe nkhani imene ingayankhe zimenezi popanda kudziwa kuchuluka kwake. Kumwa madzi ochepa a mu thanki amene mankhwala ake achepetsedwa kale mphamvu sikufanana ndi kumeza mankhwala osachepetsedwa mphamvu, ndipo palibe malire a amphaka otsimikizidwa ndi kafukufuku wowunikidwa ndi akatswiri anzawo pa madzi a thanki ya nsomba a mphamvu yochepa. Musawerengetse chithandizo kuchokera ku malangizo a thanki ya nsomba kapena ku zokambirana za milingo ya agalu. Lumikizanani ndi dokotala wa zinyama wa mphakayo, chipatala cha zinyama cha mwadzidzidzi, kapena ntchito yothandiza pa poizoni wa zinyama, muli ndi tsatanetsatane wa mankhwalawo.

Kodi ndiyenera kubweretsa mfundo ziti?

Lebulo la mankhwalawo kapena chithunzi chake, chinthu chogwira ntchito ndi kuchuluka kwake m’mankhwalawo, kuchuluka kwa mankhwala osachepetsedwa mphamvu komwe kunathiridwa m’madzi ochuluka motani ngati n’koyenera, kuchuluka koyerekezeredwa komwe mphaka wamwa, kulemera kwa mphakayo, nthawi imene anakumana ndi mankhwalawo, komanso mankhwala kapena matenda amene ali nawo panopa. Malangizo onse okhudza poizoni ochokera ku ASPCA amapempha eni nyama kuti asunge chidebe chake ndi kuimba foni m’malo modikira zizindikiro. Zimenezi zikugwiranso ntchito pano.

Utoto wafika pa ubweya. Ndichite chiyani tsopano?

Letsani mphakayo kunyambita kuti auchotse, chifukwa kuipitsidwa kwa ubweya kumakhala kukumana ndi mankhwalawa pakamwa pamene mphakayo akudzinyambita. Malangizo onse a ASPCA ochotsa zinthu zoipitsa amalimbikitsa magolovesi, sopo wamadzi wofatsa wotsukira mbale ndi madzi ofunda pochotsa zotsalira zambiri, kutsuka bwino ndi madzi, kupewa kuti mankhwalawo afike m’maso ndi m’makutu, ndi kufunsa dokotala wa zinyama njira yoyenera ya chinthucho. Funsani chipatala musanasambitse mphaka amene ali ndi nkhawa kapena zizindikiro.

Kodi ndiyenera kumusanzitsa?

Ayi, pokhapokha dokotala wa zinyama kapena katswiri wa poizoni atakuuzani momveka bwino kuti muchite zimenezo. Njira zosanzitsira kunyumba zomwe zimagwiritsidwa ntchito kwa agalu, makamaka hydrogen peroxide, si zoyenera kwa amphaka.

Kodi ndi zizindikiro ziti zimene zimafuna kuunikidwa mwamsanga?

Kufooka kapena kufooka ndi kusafuna kuchita zinthu koonekeratu, kupuma mofulumira kapena movutikira, nkhama zotuwa kapena zokhala ndi chikasu, magazi kapena minyewa ya m’kati yooneka yakuda kapena yabulauni, kugwa, kapena mkodzo wakuda. Dziwani kuti kuwonongeka kwa magazi kungachedwe kuoneka: zolemba zakale za mankhwala a njira ya mkodzo zimafotokoza kuchepa kwa magazi komwe kumayamba pakadutsa masiku. Choncho mphaka amene akuoneka bwino madzulo a tsiku limene anakumana ndi mankhwalawa amafunikirabe kuunikidwa ndi dokotala wa zinyama kuti adziwe kufulumira kwa chithandizo. Dokotalayo akalangiza, amafunikanso kuyezetsanso magazi, kuphatikizapo hematocrit ndi kufufuza zopaka magazi kuti aone tinthu ta Heinz.

Chifukwa chake malangizo a agalu ayenera kukhala osiyana

Agalu nawonso angakhale ndi kuchepa kwa magazi chifukwa cha tinthu ta Heinz zoyambitsidwa ndi methylene blue, choncho palibe pano chimene chikutanthauza kuti mankhwalawa alibe chiwopsezo kwa agalu. Koma amphaka ali ndi hemoglobin yomwe imakhudzidwa mosavuta ndi okosideshoni, maselo ofiira a magazi omwe ali ndi chitetezo chochepa, komanso ndulu yomwe siyeretsa bwino. Kuphatikizana kumeneku kumachepetsa kusiyana pakati pa mlingo wothandiza ndi wowononga. Mabuku a chithandizo amasonyeza zimenezi: njira zakale zoperekera mankhwala kwa agalu zimafika pa 4 mg pa kg kudzera mumtsempha pa zifukwa zina zoperekera mankhwalawo, pamene mabuku a amphaka nthawi zambiri amatchula 1 mpaka 1.5 mg pa kg kamodzi pa methemoglobinemia ndipo amachenjeza mwapadera za kubwereza mlingo. Kungochepetsa mlingo wa njira ya agalu molingana ndi kulemera kwa thupi kumaphonya mfundo yaikulu. Kusiyana pakati pa mlingo wothandiza ndi wowononga, mmene magazi amayankhira, ndi ndondomeko yoyang'anira zimasiyana. N’chifukwa chake zisankho zokhudza amphaka ziyenera kupangidwa ndi dokotala wa zinyama amene angayerekezere chifukwa choperekera mankhwalawo ndi chiwopsezo cha okosideshoni, n’kuyeza zotsatira zake. Kuchotsa madzi othiridwa mankhwala mu thanki mankhwalawo atagwiritsidwa ntchito, monga tafotokozera m’malangizo ochotsa mankhwala mu thanki ya nsomba, ndi ntchito yanthawi zonse yosamalira nyama. Kuchiza mphaka si ntchito yotero.