PERIOPERATIVE
MANAGEMENT OF SICKLE
CELL DISEASE PATIENTS
Ruma Anand
Yen-Phan Ta
MBBS 3 Dr D Green
May 2005
SICKLE CELL SYNDROMES
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Sickle cell disease (SCD) refers to a group of
haemoglobinopathies.
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HbSS – Sickle cell anaemia
HbSC disease
HbSD disease
HbS/β-thal - Sickle β-thalassaemia
Over 10,000 patients with SCD in Britain.
Up to 10% afro-caribbeans (AFC) in UK carry the HbS gene (i.e.
have sickle cell trait).
SCD endemic in parts of North America, Africa, Mediterranean,
Middle East and India.
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Therefore, theoretically all non-caucasian patients should
have a sickle screening preoperatively
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In practice, the test is usually restricted to AFCs
MOLECULAR BASIS OF
SICKLE CELL DISEASE
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Normal adult HbA contains 2 α chains and 2 β chains.
Homozygous for HbSS – sickle cell anaemia.
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HbS has valine substituted for glutamine in the 6th position of
β-globin chain.
HbS becomes insoluble at O2 tension in venous range 5 –
5.5kPa and crystallizes  sickling  rigid cell wall 
increased viscosity  difficult capillary passage but reforms
again in well oxygenated lung .. leads to reduced life span
Can cause occlusion and obstruction  tissue/organ infarct 
pain (these are clinical episodes known as crises).
HbSC and HbS/β-thal similar symptoms to
homozygous HbSS
Heterozygote (sickle-trait) often asymptomatic, sickling
can occur at very low oxygen tensions (below 3 kPa).
SICKLING TRIGGERS
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Hypoxaemia - isolated HbSS cell sickle at a
partial pressure of O2 less than 5.3 kPa.
Acidosis
Hypothermia
Dehydration
Low perfusion states
Infections
SICKLE CELL AND SURGERY
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Surgery requiring GA may increase risk
of vaso-occlusive events in SCD.
Sickle cell crises may be precipitated by:
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Surgical trauma and inflammatory response
to tissue injury
Hypoxia associated with ventilatory
depression (e.g. pain, opioids etc)
Dehydration induced by reduced oral fluid
intake
CLINICAL CRISES
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There exist three forms of clinical crises in patients
with SCD
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Aplastic crises produce dramatic decreases in
erythropoiesis and haematocrit levels.
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Vaso-occlusive (painful) crises
aplastic crises
splenic sequestration crises.
This is due to parvovirus infection switching off bone
marrow RBC production, catastrophic with shortened
lifespan of RBC in SCD vs normals (10 vs 120 days)
Splenic sequestration crises occur in children
younger than 6 years of age.
VASO-OCCLUSIVE CRISES
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Vaso-occlusive crises are characterized by sickling,
venous thrombosis, organ infarction, and severe pain
Sudden onset of severe pain is usually in bones and
joints.
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Bone marrow ischaemia due to sickling in bone marrow
sinusoids.
May be precipitated by:
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Infection
Exposure to cold
Unusual stress such as trauma, strenuous physical exertion,
emotional disturbance
Increased haematocrit (due to dehydration)
No apparent precipitating factor
VASO-OCCLUSIVE CRISES
MANAGEMENT
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Pain may be mild and of short duration but often
excruciating and requires hospitalisation.
Post-op painful sickle crisis may present, needs
to be distinguished from surgical pain.
Adequate and prompt pain relief
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Opioids might be required
 Can lead to respiratory depression acidosis and
hypoxia.
Pethidine is avoided due to poor efficacy, short half
life and toxic metabolite which may cause
convulsions (nor-pethidinic acid)
PRE OPERATIVE ASSESSMENT
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Sickledex: solubility test which screens for HbS.
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Haematological advice should always be sought for sickle
cell anaemia patients.
A sample for blood group and antibody screening
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Does NOT distinguish between trait and disease thus:
Haemoglobin electrophoresis is necessary to confirm the exact
phenotype. This may take time to perform so a sickle test must
be performed well before the time of an elective procedure
Previously transfused SCD patients often have red cell
antibodies.
Evidence of renal, pulmonary or cerebrovascular
complications should be assessed pre-operatively.
Check for signs of vaso-occlusion, fever, infection and
dehydration.
CARDIOVASCULAR AND RESPIRATORY
MANIFESTATIONS
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Cardiovascular manifestations result from
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Risk of pulmonary congestion due to fluid overload
during hydration for painful crisis increases with age.
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Chronic anaemia
Pulmonary arterial occlusions leading to cor pulmonale
Myocardial damage resulting from small infarcts as well as
iron deposition
Minority of adult patients will develop problems with fluid
balance.
Pulmonary dysfunction secondary to upper
respiratory tract infections, pneumonia, and
pulmonary embolization is relatively common in
patients with SC disease
ACUTE CHEST SYNDROME
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ACS is typically detected 2–3 days postoperatively.
Risk of ACS  a factor of 1.7 for every 1g/dl of Hb.
Difficult to diagnose but common characteristics:
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fever, dyspnoea, cough, chest pain and pulmonary
infiltrates
Pneumonia can trigger and complicate ACS, broadspectrum antibiotics e.g. cephalosporin and
erythromycin in combination are indicated if infection
occurs.
Arterial blood oxygen saturation commonly falls with
ACS, therefore monitor arterial blood gases rigorously.
MANAGEMENT OF ACS
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Pre-op to reduce risk of ACS:
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Transfusion
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Hydroxyurea
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Aims to  HbS level to ≈30% and
haemoglobin >10g/dl before major surgery.
The need to reduce HbS to these levels has
recently been questioned
Enhances formation of HbF
Lung function tests to assess respiratory
fitness.
SKELETAL MANIFESTATIONS
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Dactylitis (“hand-foot syndrome”)
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Often 1st manifestation of sickle cell anaemia,
predominates in children.
Result of necrosis of small tubular bones of
hands and feet  soft tissue swelling, heat and
tenderness over metacarpals and proximal
phalanges
Need urgent transfusion!
In adults the head of femur and humerus
are prone to develop infarcts, because
collateral circulation is poor.
NEUROLOGICAL MANIFESTATIONS
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Strokes are much more common in children than in
adults.
 Frequently, large arteries such as the internal
carotid or the middle cerebral are occluded
In adults, haemorrhagic strokes occur more frequently
than arterial occlusive strokes
 Subarachnoid haemorrhages are most common.
 Exchange transfusion followed by maintenance
hypertransfusion is a prudent course of action.
Pre-op management for uncovering previous ischaemic
injury:
 Transcranical doppler studies
 MRI
Note proliferative sickle retinopathy due to sickling,
stasis and occlusion of small blood vessels.
RENAL MANIFESTATIONS
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Sickle cell nephropathy, characterised by
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Defective renal concentration and acidification.
Lesions are consequence of sickling in vasa recta
(supplies blood to collecting ducts, medullary structures
etc.) of renal medulla.
Concentrating defect results due to obliteration of vasa
recta which forms part of the counter-current
multiplication system in loops of Henle.
Because of the slow blood flow and decreased local
oxygen tension, the renal medulla is particularly
vulnerable to infarction and necrosis
Papillary renal necrosis, 2° to medullary ischaemia, may
be manifest by unilateral haematuria.
Increased incidence of UTI and pyelonephritis due to
structural abnormalities and scarring.
RENAL FAILURE
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Acute renal failure may occur and is
commonly associated with dehydration
and hypovolaemia.
Chronic renal failure is an important
cause of illness and death in over 40yr
olds with SCD.
Dehydration and hypovolaemia must be
avoided.
PERI-OPERATIVE CARE 1
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If anaemia is present and severe, blood
transfusion prior to elective surgery may be
indicated.
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transfusion with normal adult hemoglobin (AA) to dilute
the sickle erythrocytes and decrease blood viscosity is
indicated (see earlier). Maximum Hb 10g dl-1
Use of a tourniquet (depending on surgery
planned) is controversial in both the homo- and
heterozygote during surgery to prevent stasis of
blood.
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If essential ensure careful wrapping of extremity,
normothermia, short compression time,
hyperoxygenation.
PERI-OPERATIVE CARE 2
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Hydroxyurea therapy prior to elective
surgery should be considered.
Prophylactic antibiotic cover should be
considered in view of SCD patient’s
increased
susceptibility
to
bacterial
infections.
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Penicillin V or clarithromycin or ciprofloxacin.
Pre-operative haematocrit should
adjusted to 30-35%, Hb +/- 10g dl-1.
be
PERI-OPERATIVE CARE 3
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Prevent sickling by avoiding
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Hypoxaemia
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By measuring oxygen saturation using pulse
oximetry and giving prophylactic oxygen.
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Oxyhaemoglobin dissociation curve is shifted to the
left.
Low arterial saturation in SCD.
During surgery and the postoperative period,
the inspired oxygen concentration should be
increased to around 40% to maintain or
increase the arterial oxygen tension.
PERI-OPERATIVE CARE 4
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Hyperviscosity
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Keep Hb around 10 gdl-1
Maintain hydration
Acidosis
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Positive pressure ventilation during surgery to
achieve normocarbia and avoid acidosis.
Aim for mild respiratory alkalosis (pH ≈ 7.45)
PERI-OPERATIVE CARE 5
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Hypotension, Hypovolaemia and Dehydration
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Avoided by volume status monitoring by central
venous catheter or oesophageal doppler.
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Depending on duration of procedure and anticipated
blood loss. Symptom free heterozygotes require less
invasive monitoring and management.
To avoid dehydration (i.e. to prevent circulatory
stasis)
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An IV infusion should always be set up preoperatively.
Allow oral fluids as late as possible and give pre- and
post-operative IV fluids.
PERI-OPERATIVE CARE 6
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Normothermia maintenance.
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Fever increases the rate of gel formation by S
haemoglobin.
Although hypothermia retards gel formation, the
decreased temperature also produces peripheral
vasoconstriction. Consequently, normothermia is
desirable.
Increasing ambient temperature in operating
room.
POST-OPERATIVE
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Continue careful observation of the
patient and monitoring of oxygenation
into the postoperative period.
Postoperative pain, analgesics, and
transient pulmonary dysfunction may
decrease arterial oxygen tension.
Consequently, supplemental oxygen
should be administered after surgery.
SUMMARY
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SCD presents with many acute as well as
chronic complications which need to be
considered in the pre-op assessment and
consequently the appropriate perioperative
care provided.
Although patients with sickle cell trait (SCT)
are at less risk than patients with SCD, the
same precautions applied to patients with
SCD should also be used for those with
SCT.