2018B06 Outline the adverse effects which could occur following the rapid transfusion
of ten units of packed red cells.

 

(note red cells in Australia are not ‘packed’)

 

List:

·         Introduction

·         Storage lesion

·         Overload

·         Dilution

·         Metabolic

·         Immune

·         Infective

 

Introduction:

Red cell unit contents

·  Red cells

·  Small volume plasma

·  Preservative: sodium, adenine, glucose, mannitol

Massive transfusion

·  50% blood volume in 4 hours, or 100% of BV in 24 hours

·  10 units = 2.5L = 50% blood volume

Ideal ratio of RBC:FFP:platelet

·  ?4:2:1

·  ?1:1:1

·  May be situation-dependent

Lethal triad

·  Acidosis

·  Hypothermia

·  Coagulopathy

 

Storage lesion: (at 4°C for 35 days)

Cells

·  Red cells: spheroidal, rigid, fragile; 25% loss at 4/52
(free Hb 1 -> 30mcg/mL)

·  White cells: inactivate but still antigenic

·  Platelets: inactivated at 48 hours?

Coag factors

·  Minimal since plasma removed

·  FV 50% at 3/52

·  FVIII 30% at 3/52

Metabolic

·  Temp 4°C

·  pH 7.4->6.7 (due to additives)

·  K+ 4->30mM

·  Ca2+ 2mmol/L -> ? (due to 3mg citrate)

·  ATP 75%

·  [2,3-DPG]: 50% at 2/52, 5% at 4/52 (due to low temp)

·  ↑Free haemoglobin

 

Overload:

Of fluid

·  ↑Blood volume -> ↑preload

·  May cause heart failure

·  High risk if LV impairment

Of iron

·  Haemolysis -> Hb breakdown -> ↑free haemoglobin

·  Risk of haemochromatosis -> damage to liver, pancreas, heart, pituitary

Of microaggregates

·  Microvascular occlusion -> multi-organ dysfunction (especially lung)

 

Dilution:

Of coag factors

·  Dilutional coagulopathy

o  Coag factors esp fibrinogen

o  Platelets

Of plasmas

·  Hyperviscosity

o  ↑risk thromboembolism

o  ↑resistance to flow, ↑myocardial work

 

Metabolic:

↓Temperature

·  Arrest if rapid via CVC

·  Coagulopathy

↓pH

·  Arrest if rapid via CVC

·  Negative inotropy

·  Generalized metabolic dysfunction

↑K+

·  Arrhythmia, arrest if rapid via CVC

·  Most K+ taken up by RBC upon transfusion

↓Ca2+

·  Arrhythmia, muscle weakness

·  (Note hypocalcaemia severe enough to cause coagulopathy would already have caused cardiac arrest)

↓2,3-DPG

·  Left shift oxy-haemoglobin dissociation curve -> ↓tissue oxygenation

 

Immunological:

Febrile non-haemolytic

·  Donor WBC -> cytokine release, fever

Febrile haemolytic

·  i.e. result if incompatible blood transfusion

·  Donor RBC Ag + host RBC Ab -> haemolysis

o  ABO intravascular

o  RhD extravascular (reticuloendothelial system)

Anaphylaxis

·  Especially IgA deficient host

TRALI

·  Donor Ab + host WBC -> non-cardiogenic APO within hours

Cancer recurrence

·  Increased risk

·  Mechanism unknown

Many others

 

 

Infective:

Bacteria

·  Septicaemia in 3% (certain pseudomonas species can multiply in the cold)

Viruses

·  HBV, HCV, HIV; CMV

Parasites

·  Malaria

CJD

 

 

 

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