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Methemoglobinemia, Refractory Cyanosis ine Normal PaO2, uye Benzocaine kana Nitrate Toxicity

Nhamba dze emergency dzinosiyana nenyika. Iri peji rinoshandisa 911, nhamba yeUnited States neCanada. Dzimwe nyika dzakawanda dzinoshandisa 112, 999, kana imwe nhamba. Tsvaga nhamba yenyika yako.

Acquired methemoglobinemia is a life-treate hematologic and toxicological emergency umo oxidizing kemikari, mishonga, kana nitrate yezvakatipoteredza inoshandura iron mukati memasero matsvuku eropa hemoglobin kubva kune yayo yakajairika oxygen-inotakura ferrous state (Fe2+) mune isiri-functional ferric state (Fe3+). Ferric methemoglobin haikwanise kusunga kana kutakura okisijeni uye inomanikidza nzvimbo dzasara dzehemoglobin dzakasara dzakabatirira paokisijeni yadzo zvekuti matishu ari muuropi nemumoyo anozarirwa. Chirwere ichi chinopa chiitiko chekiriniki chinokatyamadza: (1) slate-grey kana bluish-purple central cyanosis yemiromo, rurimi, uye ganda risinganatsiriki kana rapihwa 100% oxygen, (2) chigunwe chakajairwa pulse oximeter kuverenga kunodonha nekukiya nekusindimara kwakatenderedza 85% SpO2 zvisinei neokisijeni arterial therapy, uye ropa rakatsvuka rinoratidzika "3". yakajairika kana yakakwira yakanyungudika arterial oxygen tension (PaO2). Kana iwe uchifungidzira kuti methemoglobinemia mushure mekusangana nemusoro ** benzocaine kana lidocaine/prilocaine numbing sprays/gels **, inhaled nitrite "poppers", dapsone, phenazopyridine (AZO), kana nitrate-yakasviswa mucheche tsime remvura **, fonera yako yemuno emergency emergency nhamba dze emergency dhairekitori nekukurumidza kuitira kuti varapi vemuchipatara vagone kuendesa iyo intravenous antidote methylene blue, padivi pemirayiridzo yedu. chepfu rubatsiro rwekutanga, carbon monoxide carboxyhemoglobin triage,uye cyanide uye indasitiri gasi inhalation.

Ita izvi ikozvino

  1. ** Fonera nhamba yako yekukurumidzira yemunharaunda uye Kudzora Chepfu nekukasika **: Dial 911 muUnited States neCanada (uye US Poison Control pa 1-800-222-1222), 112 muEuropean Union, 999 muUnited Kingdom, 000 muAustralia, kana kuona nyika yedu nhamba dze emergency directory. Udza anotumira: "Inofungidzirwa Methemoglobinemia ine Refractory Cyanosis: Inoda Chipatara CO-Oximetry uye Intravenous Methylene Blue."
  2. ** Misa kuratidzwa kweoxidizing uye kusvibisa ganda kana muromo nekukurumidza **:
  3. Kana topical anesthetic cream/gel (benzocaine, EMLA lidocaine/prilocaine) yakaiswa paganda kana mumazamu: Pukuta gel rese rasara kubva mumuromo nejira rakanyorova kana kugeza ganda zvakakwana nesipo nemvura inodziya nekukurumidza kuti pasave nezvinodhaka zvinopinda nemuganda.
  4. **Kana liquid nitrites ("poppers"), aniline dyes, kana nitrobenzene yakadururwa paganda kana zvipfeko **: Bvisa zvipfeko zvakasvibiswa nekukasira uye geza ganda nemvura inoyerera kwemaminitsi gumi nemashanu wakapfeka magirovhosi.
  5. Kana mucheche akadyiswa mukaka wakasanganiswa nemvura yemutsime: Rega kushandisa mvura yemutsime nekukasika uye chinja kumvura yemubhodhoro kana yemunisiparati.
  6. Ipa 100% high-flow supplemental oxygen via non-rebreather mask uye chengetedza murwere pakuzorora zvakakwana: Kunyange zvazvo 100% okisijeni ichaita **kwete ** kwete ** pakarepo kushandura miromo yebhuruu / grey yemurwere pink kana kusundira chigunwe pulse oximeter kupfuura 85%, kufema 100% kunowedzera okisijeni inotakurwa neokisijeni yakawedzerwa muplasma yakasara isina muchetura.
  7. **Huyai nebhodhoro remishonga chaiyo, spray can, popper vial, kana mvura kukamuri yekukurumidzira *: Vanachiremba vanogona kuongorora methemoglobinemia mumaminitsi mashoma kana vakaona bhodhoro re 20% benzocaine throat/ teething spray, phenazopyridine (AZO urinary pain tablets), dapsone, *chloroquine/primaquinetrisobuty,**chloroquine/primaquine trinisobuyl
  8. Yambiro vanachiremba vechipatara VASATI vapa Methylene Blue kana murwere aine G6PD Deficiency kana kuti anwa Serotonergic Antidepressants (SSRIs/SNRIs):
  9. Kushomeka kweG6PD: Methylene yebhuruu inoda iyo enzyme G6PD (kuburitsa NADPH) kuti ishande. Muvarwere vane ** Glucose-6-Phosphate Dehydrogenase (G6PD) inoshaya **, methylene blue is ** isingabatsiri uye inokonzera kutyisa, kutyisa hupenyu hwehemolytic anemia ** (kuputika kwemasero matsvuku eropa); high-dose intravenous ascorbic acid (vitamin C), riboflavin, kana kuchinjanisa kuwedzerwa ropa kunofanira kushandiswa pachinzvimbo.
  10. SSRIs / SNRIs / MAOIs: Methylene yebhuruu ine simba **Monoamine Oxidase A (MAO-A) inhibitor ** uye inogona kukonzera serotonin syndrome muvarwere vanotora antidepressants.

Nei iyo FDA Yakarambidza Benzocaine Teething Gels yeVacheche uye Nei Imwe Spray Inogona Kushandura Mukuru Slate-Blue

Over-the-counter topical benzocaine (inotengeswa mu7.5% kusvika 20% sprays, gels, and lozenges for the pains, canker maronda, mazino, uye hemorrhoids, uye inoshandiswa muchipatara endoscopy/transesophageal echocardiogram pahuro sprays) ndiyo imwe chete inowanzowanikwa yemishonga ye methemoglobinemia yakakomba. A kamwe ka1-second kusvika 2-second spray ye20% benzocaine kuseri kwehuro, kana kukwiza benzocaine teething gel pamazino emwana, inogona kushandura 30% kusvika 60% yehemoglobin yemuviri kuita methemoglobin mukati memaminitsi gumi nemashanu kusvika makumi matanhatu. Nechikonzero ichi, iyo U.S. Food and Drug Administration (FDA), Health Canada, uye UK MHRA vakarambidza kana kupa yambiro yakasimba pamusoro pekushandisa chero chigadzirwa chebenzocaine muvacheche nevana vari pasi pemakore maviri.

Muti wesarudzo: Refractory cyanosis uye methemoglobinemia triage

flowchart TD
    Start["Murwere Anowedzera Kamwe Kamwe Slate-Grey / Bluish-Purple Central Cyanosis (Miromo, Rurimi, Mibhedha Yezvipikiri) + Kupfupika Kwekufema, Kurwadzisa Musoro, Chidzungu, kana Lethargy"] --> OxygenTest["Isa 100% Yepamusoro-Kuyerera Oxygen (15 L/min kuburikidza neNon-Rebreather Mask) uye Tarisa Finger Pulse Oximeter"]

    OxygenTest --> PlateauCheck{"Ko Cyanosis Inokundikana Kuvandudza pa100% Oxygen, UYE Ko Finger Pulse Oximeter Plateau Pedyo ne85% SpO2 (82% kusvika 88%) ine Clear Lungs paAuscultation?"}

    PlateauCheck -->|"EHE: Classic Refractory Cyanosis + 85% SpO2 Plateau"| ExposureCheck["ZVINOFUNGWA ZVINOITWA METHEMOGLOBINEMIA: Chengetedza Oxidant Triggers: 1. Topical Anesthetics: Benzocaine, Prilocaine, Lidocaine, Cetacaine 2. Nitrites / Nitrates: Poppers (amyl / isobutyl nitrite), Mucheche tsime remvura, Sodium nitrite Dariquisone, Phenazodine Medication 3. Rasburicase, Metoclopramide 4. Industrial: Aniline dyes, Nitrobenzene, Naphthalene mothballs"]

    ExposureCheck --> HospitalConfirm["Chipatara STAT Chisimbiso: 1. Dhirosa Arterial kana Venous Ropa: Cherechedza Rima Chocolate-Brown Rudzi iyo HAIshanduki yakatsvuka yakatsvuka kana ichionekwa nemhepo 2. ABG + Spectrophotometric Ropa CO-Oximetry: - Yakanyungudutswa PaO2 ndeye NORMAL kana HIGH (inopfuura 100 kusvika 300 300 mmHg, 1 inogadzira 9% ye800 mmHg) - Calculated 1% 10% Saturation Gap vs 85% SpO2 - Yakananga Measured Methemoglobin (FMetHb %) Yakasimudzwa (Kazhinji pasi pe1 kusvika 1.5%)"]

    HospitalConfirm --> SeverityTriage{"Ongorora Methemoglobin% uye Clinical Symptoms"}

    SeverityTriage -->|"MetHb 20% kana yakakwira muSymptomatic Patient OR MetHb 30% kana kupfuura muAsymptomatic Patient (Kana 10% kusvika 15% kana kupfuura kana chirwere chemoyo/mapapu kana anemia)"| G6PDCheck{"Murwere Anoziva here kana Kufungidzira Kushaya kweG6PD (kana kutora Rasburicase)?"}

    G6PDCheck -->|"HAPANA G6PD Kushaya"| GiveMB["MUTUNGAMIRIRA YEKUTANGA-LINE ANTIDOTE: INTRAVENOUS METHYLENE BLUE - Dose: 1 mg/kg kusvika 2 mg/kg (0.1 kusvika 0.2 mL/kg ye 1% solution) IV zvishoma nezvishoma pamusoro pe5 maminitsi - Co-administer IV Dextrose (D5W) kana hypoglycemic saka pentose phosphate inodonha% nzira yeHNUMX DPHly-Hyosis uye PHYHYN% mukati memaminitsi makumi matatu kusvika makumi matanhatu - Dzokorora 1 MG/kg muyero pa30 kusvika 60 min kana MetHb ikaramba yakakwira (Max yakazara dose 7 mg/kg)"]

    G6PDCheck -->|"EHE: Kuzivikanwa/Kufungidzirwa Kushaya G6PD (Methylene Blue CONTRAINDICATED)"| AltRescue["ATERNATIVE NON-G6PD RESCUE PROTOCOL: - USAPA Methylene Blue (inokonzera kuuraya hemolysis uye paradoxical MetHb kusimuka) - Kuisa High-Dose IV Ascorbic Acid (Vitamin C: 1 g kusvika 10 g IV yakakamurwa) - Funga High-Dose Riboflavin (Vhitamisiti Cellgen), kana Hyperbaric Transfusion (Vitamin B2)"]

    SeverityTriage -->|"Mild MetHb (pasi pe20%) UYE Asymptomatic ine yakajairika moyo uye mapapu basa"| ConservativeWashout["Bvisa/Decontaminate Oxidant Trigger + 100% Oxygen: Natural Cytochrome b5 Reductase enzyme inobvisa MetHb inenge 15% paawa. Nyatsotarisa kwe6 kusvika kumaawa makumi maviri nemana (tarisa Dapsone rebound)"]

Pathophysiology: Sei ferric iron (Fe3+) inokiya okisijeni uye inoshandura chokoreti yeropa-brown

1. Ferrous (Fe2+) vs. Ferric (Fe3+) Hemoglobin uye Left-Shifted Curve

Mukati mesero dzvuku reropa rega rega, hemoglobin ine cheni ina dzemapuroteni, imwe neimwe yakabata atomu resimbi pakati peporphyrin heme ring. Kuti hemoglobin isunge gasi reokisijeni (O2) mumapapu roribuditsa kuuropi nemwoyo, atomu iyoyo yesimbi inofanira kuchengetwa payakaderedzwa ferrous state (Fe2+).

Pese apo mushonga unobvisa oxidizing kana kemikari painobvisa maerekitironi kure neatomu yesimbi iyoyo, iron inoiswa oxidized mu ferric state (Fe3+), ichishandura normal hemoglobin kuita methemoglobin (MetHb). Iyi erekitironi imwe chete inoshaikwa inogadzira njodzi mbiri dzepamoyo panguva imwe chete: 1. Kurasika kwakananga kweOxygen-Carrying Capacity: Ferric iron (Fe3+) mumethemoglobin haikwanisi kusunga okisijeni zvachose; pachinzvimbo, nzvimbo yayo yechitanhatu yekubatanidza inosunga molecule yemvura (H2O) kana hydroxyl boka (OH-). 2. Allosteric Leftward Shift yeMasaiti eHeme Yakasara: Sezvakangoita kabhoni monoxide, kana imwe kana mbiri dzenzvimbo ina dzeheme muhemoglobin tetramer dzakaiswa oxidized kuFe3+, chimiro chemomoglobin molecule yese inoshanduka (allosteric cooperativity). Iyo yakasara yakajairwa Fe2+ nzvimbo dzeheme pane iyo mamorekuru **inowedzera hukama hwavo hweokisijeni **, kushandura **oxyhemoglobin dissociation curve zvakapinza kuruboshwe **. Nekuda kweizvozvo, iyo yakasara oxygenated heme nzvimbo dzinoramba kurega okisijeni yavo kana ichipfuura ne hypoxic capillaries, zvichikonzera yakanyanya cellular hypoxia uye lactic acidosis.

2. Nei Vanhu Vane Hutano Vachingove Nepasi pe1% Methemoglobin (Uye Nei Vacheche Vachinyanya Kutapukirwa)

Kunyangwe muvanhu vane hutano vanofema mhepo yakajairika, mashoma ehemoglobin anoiswa oxidized mumethemoglobin zuva rega rega (anenge 0.5% kusvika 3% pazuva). Sezvineiwo, masero matsvuku eropa ane yakavakirwa-mukati enzyme yekuchengetedza imba inonzi Cytochrome b5 Reductase (NADH-inotsamira methemoglobin reductase), iyo inotora 95% kusvika 99% yezuva nezuva methemoglobin clearance uye inoramba ichipa maerekitironi kubva kuNADH kuti idzose Fe3+ zvakare kuita Fe2+ inoshanda.

Sei vacheche vari pasi pemwedzi 4 kusvika 6 yekuberekwa vachinyanya kuuraya methemoglobinemia ("Blue Baby Syndrome") kubva mumvura yemutsime, manyoka ane acidosis, kana mazino? 1. Immature Cytochrome b5 Reductase Enzyme: Vana vachangozvarwa nevacheche vari pasi pemwedzi mina yekuberekwa vane 50% chete yezviitiko zvevakuru zvecytochrome b5 reductase, zvichireva kuti vanobvisa hafu yemethemoglobin nekukurumidza sevakuru. 2. Fetal Hemoglobin (HbF) Inoita Oxidize Kaviri Sekukurumidza: Ropa remucheche richine zvikamu zvepamusoro zvefetal hemoglobin (HbF), iyo inoiswa oxidized nekemikari kubva kuFe2+ kusvika kuFe3+ zviri nyore kupfuura Hemoglobin A yevakuru. 3. Higher Gastric pH Inobvumira Nitrate-Kushandura Hutachiona Kuti Hubudirire: Dumbu remwana mucheche rine asidi shoma (pH inodarika 4.0) pane dumbu remunhu mukuru. Iyi yakakwirira mudumbu pH inobvumira nitrate-kuderedza intestinal mabhakitiriya (E. coli, Salmonella) kukura kumusoro mudumbu remucheche uye nechepamusoro mudumbu mudiki, apo ivo vanokurumidza kushandura ** dietary nitrate (NO3-)** kubva kumatsime emvura yekumaruwa kana homemade root-vegetable purees kuita ine simba oxidizing *-nitrites.

Iwo Matatu Diagnostic Hallmarks: Chocolate Ropa, iyo 85% SpO2 Plateau, uye iyo Saturation Gap.

1. Sei Finger Pulse Oximeters Kukiya pa85% SpO2 (Beer-Lambert Optical Ratio R = 1.0)

Sezvakatsanangurwa mune yedu carbon monoxide triage guide, chiyero cheviri-wavelength chigunwe pulse oximeter chinopenya ** 660 nm (chiedza chitsvuku) ** uye ** 940 nm (infrared light) ** kuburikidza nemunwe uye inoverenga chiyero chekutora (R = Absorption pa660 nm yakakamurwa neAbsorption pa940 nm): - Yakajairika deoxyhemoglobin inotora zvakanyanya 660 nm mwenje, nepo yakajairika oxyhemoglobin inotora mamwe 940 nm mwenje. - Methemoglobin (MetHb), zvisinei, inotora zvose 660 nm chiedza chitsvuku uye 940 nm infrared chiedza zvakaenzana. - Sezvo methemoglobin inokwira muropa pamusoro pe ** 20% kusvika 35% **, inobata chiedza chechiedza pamawavelengths maviri, kumanikidzira chiyero chemaziso R chakananga ku ** 1.0 **. Pane yemukati calibration curve yakarongwa mune yega yega pulse oximeter, a optical ratio ye R = 1.0 inoenderana neSpO2 kuverenga chaiko 85% (82% kusvika 88%). - Izvi zvinogadzira gangaidzo reparutivi pemubhedha: kuti murwere ane 30% yemethemoglobin (ine zviratidzo zvinyoro) kana 70% inouraya methemoglobin (ari kufa ari pakoma), chigunwe pulse oximeter chinoramba chakaoma chando chakaoma 85% SpO2.

2. Iyo "Oxygen Saturation Gap" (Kupfuura 5% kusvika 10%) uye Normal PaO2

Kana varapi vekukurumidzira vachitora arterial blood gas (ABG) kubva kune uyu slate-blue murwere ane munwe oximeter inoverenga 85%, vanoona mhedzisiro inoshamisa: - **Arterial Oxygen Partial Pressure (PaO2) yakakwana NORMAL kana SKY-HIGH (100 kusvika 400+ mmHg paokisijeni) **, nokuti PaO2 inongoyera gasi reokisijeni rakanyungudutswa mu plasma yemvura yakajeka, iyo isingabatanidzwi ne hemoglobin. - Nekuda kwekuti muchina wegasi reropa we calculated oxygen saturation (SaO2) inotorwa nemasvomhu kubva kuPaO2 iyoyo yakajairika, muchina uyu unoshuma yakaverengwa SaO2 ye98% kusvika 100%. - Musiyano uripo pakati pe 98% kusvika 100% kaverengerwa ABG saturation uye ** 85% yemunwe pulse oximeter kuverenga ** inon Oxygen turation Gap (inopfuura 5% kusvika 10%) **, yekare diagnostic clue inonongedza zvakananga ku methemoglobinemia (kana sulfhemoglobinemia / cyanide). Kusimbisa kunoda kumhanya ropa kuburikidza ne multi-wavelength Spectrophotometric Ropa CO-Oximeter, iyo inoyera zvakananga chaiyo FMetHb%.

3. Iyo "Chocolate-Brown Ropa" Sefa-Pepa Bedside Test

Ropa remutsinga rakasviba rakasviba kuti piriviri uye rinotsvuka kutsvuka mukati memasekondi kana rasangana nemhepo yemumba kana kubhurwa neokisijeni. Kusiyana neizvi, ropa rine 15% kusvika 20% methemoglobin kana yepamusoro rine** dema chocolate-brown, rust, or espresso color** mukati mesirinji. Kana mukoti akaisa donho rimwe reropa remurwere papedhi jena kana kuti chidimbu chepepa resefa padivi pedonhwe reropa rakajairwa uye anorivheyesa mudenga kwemasekonzi makumi matatu (kana kuti achifuridza okisijeni pamusoro paro), ropa rakajairwa rinoshanduka kupenya-tsvuku cherry nepo methemoglobinemic ropa ** rinoramba rakasvibira chocolate-brown **.

Mishonga yakajairika, makemikari, uye zvitubu zvemvura zvinokonzeresa methemoglobinemia

Oxidant Category Chaiyo Mishonga, Makemikari, kana Matsime Typical Exposure Scenario & Clinical Nuances
Topical & Local Anesthetics (Chipatara Chinonyanya Kuzivikanwa/OTC Chikonzero) ** Benzocaine ** ( Hurricaine spray, Orajel, Cepacol, Vagisil, Anbesol), ** Prilocaine ** ( EMLA cream), ** Lidocaine **, ** Tetracaine / Cetacaine **. Kumwaya huro pamberi pekumusoro endoscopy, bronchoscopy, kana transesophageal echocardiography (TEE), kana kunyanya-kuzora numbing creams usati wabvisa laser bvudzi, nyora, kana mazino. Kutanga kunokurumidza-kukurumidza (maminitsi gumi nemashanu kusvika makumi matanhatu).
Volatile Nitrites ("Poppers") & Intentional Sodium Nitrite ** Amyl nitrite, isobutyl nitrite, alkyl nitrites ** ("Rush", "Jungle Juice", "dehwe rekuchenesa" rinofemerwa nekuvaraidza), kana kumwiwa ** sodium nitrite ** (nyama inorapa munyu). Kufemba "poppers" kunokonzera kukurumidza kubhururuka uye ine mwero MetHb; ** kunwa mapopu emvura kana kunwa sodium nitrite kunokonzera yakakura, inokurumidza kuuraya methemoglobinemia (60% kusvika 90%) mukati me15 kusvika kumaminitsi makumi matatu ** inoda pakarepo high-dose methylene blue.
Kunyorerwa Maantimicrobials & Urological Drugs Dapsone (inoshandiswa kune maperembudzi, Pneumocystis PJP prophylaxis, dermatitis herpetiformis, uye inowanikwa seyakashata mumugwagwa), Phenazopyridine (AZO / Pyridium) (pamusoro pe-the-counter urinary tract pain pill inoshandura weti yakajeka orenji), Primaquine /sChloroquine, Sulfineona, Sulfineona**, Sulfineona*, Sulfineona*, Sulfonemide* ** Metoclopramide **, ** Nitroglycerin ** (yakakwirira-dose IV), ** Rasburicase **. ** Dapsone Warning : Dapsone inogadziriswa muchiropa kune ine simba hydroxylamine oxidant inopinda enterohepatic recirculation ** ine hafu yehupenyu hwe20 kusvika 30+ maawa, zvinoreva ** methemoglobinemia inowanzodzorera 4 kusvika kumaawa 12 mushure mekutanga dose yemethylenesing blue uye kudzokorora kudzokorora kunoda nguva yakawanda ye methylenesing blue uye kudzokorora. activated charcoal).
Mvura Yemucheche Mvura & Dietary Nitrates ("Blue Baby Syndrome") Yakavanzika isina kudzika mvura yemutsime yekurima yakasvibiswa nefetereza kana manyowa ezvipfuyo (Nitrate-Nitrogen inodarika 10 mg/L [10 ppm], kana Nitrate yose inodarika 45 kusvika 50 mg/L), kana mapuree evacheche espinach, beet, makarotsi, kana kuti squash akachengetwa kumba. Kufashaidza mvura yemutsime HAKUBVISI manitrates: kufashaidza kunoita kuti mvura ive mhute uye INOKONISA ma nitrates anouraya zvakanyanya. Kurova vacheche vari pasi pemwedzi 4 kusvika 6 yekuberekwa.
Makemikari eMaindasitiri & Zvigadzirwa zvemumba Madhayi eAniline (porishi yeshangu, ingi yekuwachira, makrayoni), Nitrobenzene, Naphthalene mothballs (inokonzeresawo hemolysis yakakomba mukushaikwa kweG6PD), Chlorates (zvinouraya masora/matches), Copper sulfate, *exhaust yemotokari. Dermal absorption kuburikidza nekubatana kweganda nezvinonyungudutsa zvemaindasitiri kana machira achangobva kudhayiwa anoitika nekukurumidza sekufemerwa kana kupinza.

Clinical severity ladder: Zviratidzo neMethemoglobin percentage (MetHb%)

*(Cherechedza: Zvikamu izvi zvinotora hutano hwekutanga hemoglobin ye14 kusvika ku15 g/dL. Kana murwere atova ne anemia [somuenzaniso, hemoglobin 8 g/dL], kutadza kushanda kwemwoyo, kana COPD, zviratidzo zvakakomba zvehypoxic zvinoonekwa pa hafu yezvikamu izvi nokuti vane hemoglobin isingashande zvikuru yasara.)

Ropa Methemoglobin Level (FMetHb%) Kuonekwa Kwemuviri & Zviratidzo zveMakiriniki Neurological, Cardiac & Systemic Symptoms Standard Hospital Action
0% kusvika 1.5% (Yakajairwa Baseline) Normal pink mucous membranes; SpO2 = 97% kusvika 100%. Hapana. Normal physiological state.
** 3% kusvika 15% (Yekutanga / Nyoro)** Yakacheneruka, grey, kana ** slate-blue ruvara rwemiromo nemibhedha yezvipikiri** (central cyanosis inozoonekwa kamwe chete zvachose MetHb inodarika 1.5 g/dL, yakaenzana ne10% MetHb); pulse oximeter inotanga kudonha yakananga 88% kusvika 92%. Kazhinji ** asymptomatic ** pakuzorora, kana nyoro musoro uye kuneta. Rega kugumbura mumiririri; nyatsoongorora.
15% kusvika 30% (Zviri pakati nepakati) ** Yakadudzwa slate-grey / bluish-yepepuru central cyanosis ** isingateereri kuokisijeni; ** ropa rinooneka rima chokoreti-brown **; pulse oximeter ** inokiya paanenge 85% SpO2 **. Kurwadza kwemusoro, dzungu, kuchena musoro, kufunganya, kutadza kufema zvakanaka paunenge uchishanda nesimba, tachycardia (kupfuura 100 bpm), uye kupera simba zvachose. Ipa IV Methylene Bhuruu (1 kusvika 2 mg/kg) kana iine zviratidzo (kana kana 20% kana yakakwirira paine chero zviratidzo, kana 10% kusvika 15% kana yakakwirira neiyo iri pasi pemoyo / yemapapu chirwere kana anemia).
** 30% kusvika 50% (Yakaoma) ** Yakadzika yebhuruu-grey cyanosis pachiso, rurimi, uye torso; tachypnea (kukurumidza kufema). Dyspnea yakanyanya, confusion, lethargy, syncope (fainting), kurwadziwa muchipfuva (myocardial ischemia), palpitations, uye early lactic acidosis. ** Pakarepo STAT IV Methylene Blue (1 kusvika 2 mg / kg pamusoro pe5 min) ** + 100% O2 + inopfuurira kutarisa kwemwoyo.
**50% kusvika 70% (Yakaoma / Hupenyu-Kutyisidzira) ** Yakadzika cyanosis, hypotension, bradycardia kana ventricular arrhythmias. Stupor, coma, generalized tonic-clonic seizures, yakanyanya metabolic lactic acidosis (pH pasi pe7.15), cardiac ischemia, uye kuvhunduka. ** STAT IV Methylene Blue (1 kusvika 2 mg / kg, inodzokororwa mu 30 min kana zvichidiwa) ** + endotracheal intubation ne 100% O2 + gadzirira kuchinjana kuwedzerwa ropa kana refractory.
** Pamusoro pe70% (Kazhinji Inouraya Pasina Kununura Pakarepo) ** Agonal gasping, circulatory collapse. **Hypoxic cardiac kusungwa uye kufa mukati memaminitsi ** kunze kwekunge adzoserwa pakarepo. STAT IV Methylene Blue + ACLS resuscitation + kubuda ropa tsvuku sero kuchinjanisa kuwedzerwa / hyperbaric oxygen.

Mashandiro eAntidote Methylene Blue Anoshanda (Uye G6PD Kushaya Musungo)

1. Iyo Diki NADPH Nzira Iyo Methylene Bhuruu Inomhanyisa

Mumamiriro ezvinhu akajairika, masero matsvuku eropa anoshandisa ** NADH-inotsamira Cytochrome b5 Reductase nzira ** kubvisa 99% yezuva nezuva methemoglobin. Zvisinei, masero matsvuku eropa anewo yechipiri, inowanzogara yakarara enzyme inonzi NADPH-Methemoglobin Reductase, inoshandisa NADPH yakagadzirwa ne Glucose-6-Phosphate Dehydrogenase (G6PD) mupentose phosphate pathway (hexose monophosphate shunt).

Payo pachayo, NADPH-Methemoglobin Reductase inoshanda zvishoma nezvishoma nekuti inoshaya yakasikwa maelectron-shuttle carrier. Intravenous Methylene Blue (1 kusvika 2 mg/kg yemushonga we1% [10 mg/mL] wakaiswa zvishoma nezvishoma kwemaminetsi mashanu) inoshanda se yakagadzirwa maelectron shuttle: 1. Mukati mesero dzvuku reropa, NADPH-Methemoglobin Reductase inoshandisa NADPH (yakagadzirwa neG6PD) kuderedza bhuruu Methylene Blue kuva isina ruvara ** Leukomethylene Blue**. 2. Leukomethylene Blue pakarepo inopa maerekitironi ayo zvakananga kune ferric iron (Fe3+) ye methemoglobin, ichiidzorera muyakajairika oxygen-inotakura ferrous iron (Fe2+) hemoglobin mukati 30 kusvika 60 maminetsi. 3. (Practical Clinical Tip: Nekuti masero matsvuku eropa anoda glucose kuti amhanye pentose phosphate nzira uye kugadzira NADPH, muchipatara toxicologists vanoongorora kuti murwere ane yakajairika shuga yeropa, kana kuisa methylene yebhuruu ne 5% Dextrose [D5W], saka masero matsvuku eropa haamboperi mafuta emushonga.) 4. (Pulse Oximeter Note Mushure meKupa Methylene Bhuruu: Nekuti methylene bhuruu dhayi yakadzika yebhuruu inotenderera muropa inotora 660 nm mwenje dzvuku zvine simba, ** kubaya intravenous methylene blue kwechinguva kuchaita kuti chigunwe pulse oximeter kuverenga kudonhe zvakanyanya kusvika 65% kusvika 2 kusvika 75% inokuvadza * maminetsi maviri kusvika makumi manomwe neshanu. weti uye ganda rakajeka-ruvara rwegirinhi kwemaawa makumi maviri nemana kusvika makumi mana nemasere.)

2. Sei Methylene Bhuruu Ichinyatsopikiswa muG6PD Kushaya (Uye Pamusoro pe7 mg/kg)

  • The G6PD Deficiency Trap: Nekuti methylene blue inonyatsoenderana neNADPH inogadzirwa neG6PD enzyme, murwere ane Glucose-6-Phosphate Dehydrogenase (G6PD) deficiency (an X-linked genetic condition inowanikwa muvanhu vekuMediterranean, Africa, Middle Eastern, uye Southeast Asian cannot blueukogemethyl* blueukogemethyl Zvakatonyanya, methylene yeblue isina kudzikiswa inoita seoxidant inoba chero diki diki rekuchengetedza glutathione iyo G6PD-inoshomeka sero yasara, zvichikonzera massive acute Heinz-body hemolytic anemia (kuparadza masero matsvuku eropa) uye zvinoshamisa kuti methemoglobinemia iwedzere.
  • **Zvinoshandiswa navanachiremba panzvimbo paG6PD Deficiency **: High-dose intravenous Ascorbic Acid (Vitamin C: 1 kusvika 2 gramu IV maawa matanhatu oga oga, kusvika ku10 gramu mumatambudziko akaoma) (iyo inoderedza methemoglobin zvakananga pasina inoda G6PD/NADPH, kunyange zvishoma nezvishoma kupfuura maawa gumi nemaviri kusvika ku24), intravenous *Byflavenous VitaminH24 maawa), intravenous Byflavenous, Vitamin B24, intravenous. Oxygen Therapy (HBOT), kana otomatiki Red Blood Cell Exchange Transfusion.
  • Iyo 7 mg/kg Ceiling: Kunyangwe muvarwere vane G6PD yakajairwa, methylene bhuruu idhayi inobvisa oxidizing pamadosi akawandisa. Total cumulative methylene blue dosing inofanira ** kusambopfuura 7 milligrams pakirogiramu**, sezvo madosi ari pamusoro pe7 mg/kg achikonzera kurwadziwa muchipfuva, dyspnea, hemolysis, uye ** zvinoshamisa zvinokurudzira methemoglobinemia**.
  • Sulfhemoglobinemia Mimic: Mimwe mishonga ine sulfuri (yakadai sesumatriptan, phenazopyridine, dapsone, kana metoclopramide*) dzimwe nguva inogona kuisa oxidize hemoglobin uye kuisa atomu resarufa mumhete yeporphyrin, zvichiita ** sulfhemoglobin (SulfHb)**. Sulfhemoglobin inotaridzika zvakafanana nemethemoglobin (cyanosis, chokoreti ropa, 85% SpO2) kunze kwekuti sulfhemoglobin haidzoreki uye haipinduri kune methylene blue (inoda rubatsiro rwekutsigira kana kuchinjana kuwedzerwa kusvikira masero matsvuku eropa atendeuka).

Nhamba dzenharaunda dzechimbichimbi uye zvirongwa zveagency

  • United States neCanada: Fonera 911 nekukasika wobvunza Poison Control pa1-800-222-1222 (US) kana 1-844-POISON-X (Canada). Chipatara chega chega dhipatimendi rekukurumidzira rinotakura ** 1% Methylene Blue jekiseni (ProvayBlue, 50 mg/10 mL [5 mg/mL] kana 10 mg/mL mabhodhoro)** pasi pe American College of Medical Toxicology (ACMT) uye AAPCC antidote stocking guidelines. Kuchengetedzeka kwemvura mutsime kunotevera U.S. EPA Maximum Contaminant Level (MCL) ye10 mg/L Nitrate-Nitrogen.
  • United Kingdom: Fonera 999 ye ambulensi yechimbichimbi (kana NHS 111 / **NPIS TOXBASE ** yekutungamira kwekiriniki). MuUK, mushonga unobaya jekiseni unonzi Methylthioninium chloride (Methylene Blue) uye wakachengetwa seCategory A immediate emergency department antidote pasi pe **Royal College of Emergency Medicine (RCEM) uye NPIS ** nhungamiro.
  • European Union: Dial 112 munyika dzese dziri nhengo dzeEU. Zvikwata zvezvipatara zvinopa Methylthioninium chloride (Proveblue) inotevera European Medicines Agency (EMA) uye mitemo yenyika ine chepfu; mvura yekunwa nitrate inodzorwa pasi pe EU Nitrates Directive (50 mg/L se NO3-).
  • Australia neNew Zealand: Fonera 000 muAustralia kana 111 muNew Zealand, uye bvunza Poisons Information Center pa13 11 26 (Australia) kana 0800 764 766 (New Zealand).
  • India neAsia-Pacific: Dial 112 muIndia, 995 muSingapore, 119 muJapan neSouth Korea, kana 999 muHong Kong neMalaysia. Munzvimbo dzekurima nemaindasitiri ekugadzira dhayi, aniline, nitrobenzene, uye chepfu yenitrate yekurima inogadziriswa nekukurumidzira kusvibiswa kweganda, intravenous methylene blue, uye G6PD kuongorora.

Mibvunzo inowanzo bvunzwa

Sei chigunwe pulse oximeter ichidonha kusvika pa85% uye inoramba yakanamatira ipapo panguva yemethemoglobinemia?

A standard clip-on finger pulse oximeter inoverengera kuzara kweokisijeni nekuyera reshiyo yechiedza chakatorwa pamawavelength maviri: 660 nanometers (chiedza chitsvuku) uye 940 nanometers (infrared light). Nepo yakajairika oxygenated uye deoxygenated hemoglobin inotora aya mawavelengths maviri akasiyana zvakanyanya, ferric methemoglobin inotora ese 660 nm uye 940 nm mwenje zvakaenzana, ichityaira iyo yekuona absorption reshiyo kusvika 1.0. Mukati mese yakajairwa pulse oximeter's software, absorption reshiyo ye1.0 inoturikira kuSpO2 kuverenga kunosvika 85%. Nokudaro, kana methemoglobin yadarika 25% kusvika 35%, oximeter inokiya pedyo ne85% kana murwere ari kurwara zvishoma kana kufa zvakanyanya pa 70% methemoglobin.

Sei zvine njodzi kubikira mvura yemutsime yakavanzika kugadzira mukaka wemucheche kana mvura iine nitrate?

Kusiyana nemabhakitiriya kana mavhairasi, nitrate inonyungudutswa kemikari munyu isingabudi kana mvura yabikwa. Paunenge uchibika mvura ine nitrate-yakasvibiswa mvura pachitofu, tsvina yakachena inoputika apo 100 muzana yenitrate inosara muhari, zvichiita kuti nitrate iwedzere uye ine ngozi kumwana. Matsime ekumaruwa ega ega anofanira kuongororwa gore negore kuti ane nitrate (anofanira kunge ari pasi pe10 mg/L Nitrate-Nitrogen) asati amboshandiswa kusanganisa mukaka wemucheche wevana vari pasi pemwedzi mitanhatu yekuberekwa.

Sei ropa remurwere rakaita kunge muto wechokoreti yakasviba apo mukoti akaridhirowa muimba yekukurumidzira?

Normal hemoglobin ine ferrous iron (Fe2+) inoshanduka tsvuku tsvuku kana yangosunga oxygen. Kana oxidizing kemikari senge benzocaine, nitrites, kana dapsone ichishandura iron iyoyo kuita ferric state (Fe3+ / methemoglobin), iyo yakashandurwa heme ring haigoni kusunga okisijeni uye inoratidza chiedza murima rakasvibira. Pese pazvinoita methemoglobin inopfuura 15% kusvika 20% yehemoglobin yakazara, zvese zviri zviviri arterial uye venous ropa rinotora rakasiyana nechokoreti-brown color iyo inotadza kutsvuka kunyangwe ikasangana nemhepo yemukamuri kana oxygen yakachena.

Sei vanachiremba vasingakwanise kupa mushonga weMethylene Blue kune mumwe munhu ane G6PD kushomeka?

Methylene yebhuruu haideredzi methemoglobin zvakananga pachayo; mukati mesero dzvuku reropa, inofanira kutanga yashandurwa kuita leukomethylene yebhuruu inoshanda uchishandisa NADPH inogadzirwa neiyo enzyme Glucose-6-Phosphate Dehydrogenase (G6PD). Kana murwere aine G6PD kushomeka, masero matsvuku eropa haagone kuburitsa NADPH yakakwana kuti ishandise methylene yebhuruu. Pane kudaro, iyo isina kuderedzwa methylene blue inoita seoxidant inoparadza sero rinodzivirira glutathione, zvichikonzera kuputika kukuru kwemasero matsvuku eropa (acute hemolytic anemia) pasina kugadzirisa methemoglobinemia. Vanachiremba vanorapa varwere vane G6PD-vanoshaya vane high-dose intravenous vhitamini C (ascorbic acid) kana tsvuku yeropa kuchinjanisa kuwedzerwa.

Sei weti yemurwere yakapenya yebhuruu-girinhi uye pulse oximeter yadonha kusvika 70% mushure mekuwana mushonga weMethylene Blue?

Zvose zvinokonzerwa zvinotarisirwa zvachose uye hazvikuvadzi. Methylene bhuruu idhayi yekurapa yebhuruu yakadzika: sezvainotenderera muropa mumaminetsi maviri kusvika gumi ekutanga mushure mekusundidzira IV, dhayi yebhuruu pachayo inotora 660 nm dzvuku mwenje pamunwe, zvichikonzera kunyura kwekanguva pamunwe pulse oximeter kunyangwe ganda remurwere richichinja pink uye ropa ravo rechokwadi rinoyerera pa CO-hemoglobino. Itsvo dzinobva dzasefa dhayi muweti, dzoshandura weti kuti ive yebhuruu kana kuti yegirinhi kwemaawa 24 kusvika ku48.

*Nhungamiro iyi inopa ruzivo rwedzidzo yekukurumidzira uye haitsivire nyanzvi yekurapa kana kubvunza Poison Control. Nekuti yakanyanya methemoglobinemia inokonzeresa kukurumidza cellular hypoxia, pfari, uye kusungwa kwemoyo, tinokurudzira zvakasimba kutora yakasimbiswa maoko-parubatsiro rwekutanga uye CPR kosi kubva kuRed Cross, St John Ambulance, kana yakatenderwa yemuno kudzidzisa mupi.

Mazano anoenderana

Nzvimbo uye nhungamiro yepamutemo

  • American College of Medical Toxicology (ACMT) uye American Association of Poison Control Centers (AAPCC, United States): Nyanzvi Kubvumirana Mirayiridzo yeStocking and Administration of Antidotes in Emergency Departments: Intravenous Methylene Blue for Acquired Methemoglobinemia.
  • U.S. Food and Drug Administration (FDA, United States) neMishonga neHealthcare products Regulatory Agency (MHRA, United Kingdom): Drug Safety Communications: Njodzi Yezvakakomba uye Zvingangofatal Blood Disorder (Methemoglobinemia) ine Over-the-Counter Benzocaine Teething Zvigadzirwa uye Topical Anesthetic Sprays.
  • World Health Organization (WHO) neU.S. Environmental Protection Agency (EPA): Nhungamiro yeKunwa-Mvura Unhu: Nitrate uye Nitrite muKunwa-Mvura uye Kudzivirira Kwecheche Methemoglobinemia.
  • National Poisons Information Service (NPIS / TOXBASE) uye Royal College yeEmergency Medicine (RCEM, United Kingdom): Antidote Guideline yeMethylthioninium Chloride (Methylene Blue) muMethaemoglobinaemia uye Management muG6PD Deficiency.
  • European Medicines Agency (EMA): Chidimbu cheChigadzirwa Chimiro uye Clinical Dosing Protocol yeProveblue (Methylthioninium Chloride) muPediatric and Adult Acquired Methemoglobinemia.