Search Medical Lecture Notes


medicalpptonline.blogspot.com contains lecture notes in most fields of medicine. You can directly copy lectures to your laptop ,no need of downloading or streaming

Lectures are collected from various sources.I will not be responsible for any typing error and out dated medical facts.Visitors are advised to cross check the information

Please give the authors the credit they deserve and do not change the author's name

If any of of you have a good personal power point presentations
Email me i will upload it here.

Blood Transfusion Reactions



Objectives
 Early identification of common transfusion rxns.
 Differentiate life threatening reactions from benign transfusion rxns.
 Manage common immunologic tranx rxns.


Types of Reactions
Immune mediated transfusion reactions
 Febrile non hemolytic tranx rxns
 Immune mediated hemolysis
---Acute and delayed hemolytic reactions
 Anaphylactic transfusion rxns
 Urticarial transfusion rxns
 Post-transfusion purpura
 GVHD
 TRALI (pulm leuko-agglutinin reactions)


Non immune mediated reactions
 Physical reactions: thermal i.e. heat or cold induced
 Infectious; Hepatitis B/C, malaria, HIV, CMV, Chagas dx, CJ Virus, West Nile virus
 Chemical; citrate toxicity, hypo/hyperkalemia, iron overload
 Acute hypotensive reaction: mediated by bradykinins and occurs in patients with faulty bradykinin metabolism on ACE I
 Osmotic injury
 Congenital and acquired hemolytic anemia
Immunologic rxns
classic blood tranx rxns are usually immunologic and occur 2/2 to interactions of inherited/ acquired Ab with foreign Ag from transfused blood
Incidence of rxns
SHOT trial (serious hazards of tranx)
-most common cause is tranx of non-matched blood mostly 2/2 to clerical error
-2x more common in infants than adults
-more common in pxts with hematological and oncological conditions

Case scenario 1
 A 35-year-old woman was hospitalized for anemia 2/2 sickle cell disease, she is receiving 2 units of PRBC. After her 1st unit of blood she developed a temp of 38.3 °C (101.0°F). She has no other symptoms.
On exam she appears anxious but her vital signs are stable with Bp 120/70mmHg, HR 80bpm 18cpm Pox 98% 0n RA
She has no skin rash and her urine color is amber

What are your differential diagnosis and how would you manage this pxt?



Febrile non hemolytic tranx rxns
 Most common, usually benign without sequelae
 Concerning because initial presentation is similar to more adverse rxns. i.e. fever, chills +/- mild dyspnea.
 15% will have a rxn in the future with subsequent tranx

Etiology
 Class 1 HLA ab directed against contaminating wbc in red cell conc. Although these are not always found
 2/2 to cytokines IL-1, 6,8 and Tnf alpha generated in stored blood/products.
 Determining factor is age of blood products

Management
Discontinue tranx, rule out hemolysis i.e. check labels, repeat type and cross, coombs test
Antipyretics +/- meperidine for chills and rigors

Case scenario 2
 A 35-year-old woman was hospitalized for anemia 2/2 sickle cell disease, she is receiving 2 units of PRBC. Her 1st unit of blood was transfused without events but 5minutes into her 2nd unit, She complains of new flank pain and fever.

On exam she appears very anxious, diaphoretic and in acute distress, she is febrile to 38.8C with Bp 100/60mmHg, HR 101 bpm, 18cpm, Pox 98% 0n RA
She has no skin rash but is oozing out of IV sites and her urine color is now reddish brown.

Labs: elevated Bun/creat, increased PTT, PT and decreased HCT.

What is the diagnosis and how would you manage this patient?

Acute hemolytic rxns
 Medical emergency
 Occurs due to rapid transfused RBC destruction by preformed recipients Abs
 Mostly 2/2 to ABO incompatibility-typically type O receiving non O blood. May occur with other blood types
 IgM mediated complement fixation leading to rapid intra vascular hemolysis
 Most common causes are clerical or procedural errors
 Complications includes DIC, shock, ARF 2/2 to ATN






Case scenario 3
 30 year old kidney transplant recipient on chronic Immunosupressive therapy admitted for anemia and received 2 units of non irradiated PRBC from his sister 3 days ago develops skin bullae, diarrhea and abdominal cramps
VS: notable for low grade fever of 37.9C otherwise normal
PE: Jaundice, swollen skin with multiple bulla

Labs; new thrombocytopenia, elevated LFT, increased bilirubin.

What is your diagnosis?
Transfusion associated
GVHD
 Very rare (0.1-1%) complication seen in Immuno-compromised individuals esp in solid tumor cancer pxts on chemo, but can occur with acute/chronic leukemia, lymphomas, new borne with erythroblastosis fetalis and transplant pxts

 Different from transplant GVHD by it’s effect on bone marrow (BM aplasia)

 It occurs in immuno-compromised recipients of blood products from donors with identical HLA haplotypes. They are heterozygous for a HLA haplotype for which the donor is homozygous .e.g. genetically identical relatives

HLA ag are shared by donor and recipient, thus donor lymphocyte are engrafted by recipient because they are the only Ag seen by the host.

On the flip side the donor lymphocytes view the recipient’s tissues as foreign leading to immunologic activation and GVHD.

 Bone marrow aplasia is the primary cause of death

Clinical presentation
Skin: Swollen, erythroderma and bullae formation- most common
GI: Diarrhea and abdominal cramps
Liver: Elevated LFT and Hyperbilirubinemia
Heme: Bone marrow aplasia, persistent thrombocytopenia



 Non Irradiated whole blood
 PRBC
 Platelets
 Granulocytes
 Fresh non frozen plasma
It has not been seen with frozen deglycerolized RBC, FFP or Cryoprecipitate

Treatment
Poor response to standard immunosuppressive therapies,
Thalidomide has been tried with variable success.

Prevention
Key since response to treatment is poor
Gamma irradiation and leuko-reduction of products
Avoid blood products from genetically identical donors

Case scenario 4
 A 35-year-old woman was hospitalized for thrombotic thrombocytopenic purpura for which she underwent therapeutic plasma exchange with fresh frozen plasma. After 7 days of treatment, she had improved sufficiently to allow for weaning from daily transfusions; however, at the conclusion of plasma exchange, she developed a cough and a temperature of 38.3 °C (101.0 °F), with progression of respiratory symptoms to severe dyspnea, with some wheezing.

On physical examination, the blood pressure is 120/80 mm Hg. There is no rash or hives. She is tachycardic and cyanotic on cardiopulmonary examination. Oxygen saturation is 80% on room air, and a blood gas study shows an arterial PO2 of 55 mm Hg. A chest radiograph reveals diffuse opacifications of both lungs and a normal-sized heart and no pleural effusion.

Which of the following is the most likely cause for this patient's reaction?

 Pulmonary embolism
 Antileukocyte antibodies
 Allergy to donor plasma proteins
 Circulatory overload

Transfusion related acute lung injury
 New acute lung injury occurring during or within 6 hour of blood product tranx
 All blood products have been implicated
 May progress to ARDs
 Immune mediated non cardiogenic pulm edema

Risk factors
No definite risk factors but prolonged storage of blood products, massive tranx, cytokine txt, multiparity, thrombocytopenia and active infections have been implicated in a number of studies.

 Leading cause of transfusion related fatalities in the USA
 1 case for every 1000-2400 units transfused
 6-9% mortality rate
Pathogenesis
-Abs against HLA
-2 hit hypothesis:
1st hit is an underlying pulm pathology that leads to localization of neutrophils in the pulm vasculature 2nd hit is the transfusion of blood products containing sensitized neutrophils Ab leading to release of vasoactive Cytokine and pulm edema

Clinical presentation
 Acute onset of respiratory distress (hypoxemia) during or shortly after blood tranx. On the average within 1-2 hours post tranx
 Fever, tachycardia, tachypnea, +/-hypotension
 In intubated pxts; elevated peak airway pressures, pink frothy airway secretion
 CXR bilateral patchy alveolar infiltrates, normal cardiac picture
 Labs; eosinophilia and transient drop in neutrophils, Leuko-agglutinin testing

Diagnosis
Clinical presentation and CXR findings
-Labs; granulocyte/ leuko-agglutinating abs, decline in C3 or C5 levels 12-36 hours after onset of symptoms followed by rise 4-7 days later




Ddx includes
 Acute fluid overload: ↑ JVP, ↑SBP and widened pulse pressure during dyspneic episode, ↑ pulm vascular markings on CXR
 Hemolytic transfusion rxns
 IgA mediated anaphylaxis in IgA def patients

Conclusion
 Transfusion reactions are mostly due to clerical errors and can range from benign reactions to life threatening emergencies
 Early detection, discontinuation of transfusion and instituting supportive care are key to management.
 Reporting of all reactions helps to improve standard practices and reduce future occurrences.

 Kleinman S, Caulfield T, Chan P, Davenport R, McFarland J, McPhedran S, et al. Toward an understanding of transfusion-related acute lung injury: statement of a consensus panel. Transfusion. 2004;44:1774-89. [PMID: 15584994] [PubMed]
 Beauregard P et al. Hemolytic and pseudo- hemolytic reactions: AN overview of hemolytic reactions and the clinical conditions that mimic them. Transfus Med Rev 1994; 8:184
 Brittingham, TE et al. Febrile transfusion reactions caused by sensitivity to donor leukocytes and platelets J Am Med Assoc 1957 165:819
 Sanders RP et al. A revised classification scheme for acute transfusion reactions. Transfusion 2007 47;621.
 Stack G et al; Cytokine generation in stored platelet concentrates; Transfusion 1994
 Uhlmann ET et al. Prestorage universal WBC reduction of RBC units does not affect the incidence of transfusion reactions. Transfusion 2001 41; 997
 Tobian AA et al. Transfusion premedication: a growing practice not based on evidence.. Transfusion 2007; 78;1337
 Murphy MP et al. Prevention of bedside errors in transfusion medicine (PROBE-TM) study: a cluster-randomized, matched-paired clinical areas trial of a simple intervention to reduce errors in the pre transfusion bedside check. Transfusion 2007 47:771
 Shimada E et al. Anaphylactic transfusion reactions in haptoglobin-deficient patients with anti-haptoglobin Abs. Transfusion 2002
 Vassallo RR: Review IgA anaphylactic transfusion reactions Part 1. Lab diagnosis, incidence and supply of IgA def products. Immune hematol 2004
 Kopko PM, Marshall CS, MacKenzie MR, Holland PV, Popovsky MA. Transfusion-related acute lung injury: report of a clinical look-back investigation. JAMA 2002;287:1968-71. [PMID: 11960539] [PubMed
 Toy, P Popovsky et al, Transfusion-related acute lung injury; Definition and review. Crit Care Med 2005: 33:721

No comments:

Post a Comment

Related Posts Plugin for WordPress, Blogger...