Dr. S. Parthasarathy MD., DA., DNB, MD (Acu), Dip. Diab.DCA, Dip. Software statistics PhD (physio)...

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Transcript of Dr. S. Parthasarathy MD., DA., DNB, MD (Acu), Dip. Diab.DCA, Dip. Software statistics PhD (physio)...

SICKLE CELL DISEASE AND ANAESTHESIA

Dr. S. Parthasarathy

MD., DA., DNB, MD (Acu), Dip. Diab.DCA, Dip. Software statisticsPhD (physio)Mahatma Gandhi medical college and research institute , puducherry – India

What is this?

Edward Irons in Noel - 1904

Normally Hb consists of alpha and beta chains

Normal is Hb A Foetal is Hb F

What is it?

Sickle cell disease is a genetically

inherited abnormality of

haemoglobin in which valine replaces

glutamine at the sixth position on the

beta chains of the haemoglobin

molecule. This haemoglobin is

termed Haemoglobin S (usually

written HbS).

Hb AA - normal Hb AS – sickle cell trait 20-40% HbSS – sickle cell disease 85 – 90%

when HbS becomes deoxygenated it comes out of solution forming long crystals called "tactoids" which distort the red cell.

Sickling

Microscopy

Shape abnormal – ok ??

Deoxygenated HbS is 50 times less soluble in blood than deoxygenated HbA.

it comes out of solution forming long crystals called "tactoids" which distort the red cell and cause it to become crescent shaped.

Initially this is reversible with oxygenation but repeated sickling in the low oxygen tension of the microcirculation causes membrane damage. The cell wall becomes brittle and permanently deformed or "sickled

Major problems

Life span 10 – 20 days instead of ______

chronic haemolytic anaemia with a haemoglobin of around 5-8g/dl.

The structural change and associated increase in blood viscosity promotes venous stasis

Blood flow compromise and tissue infarction

Precipitators

HbF Acidosis Hypoxemia Venous stasis Dehydration Infections

Clinical scenario

Patients with sickle trait are usually fit and healthy

Sickle cell disease Hb F normally is 1 % - protects Childhood onset to go on till

40-50 years

Presentation

Pain crises or VOC Thigh Lumbar Knees

Later on splenic infarct, renal failure but death due to ACS and stroke

Respiratory - the "acute chest syndrome".

Dyspnoea, cough , haemoptysis and pleuritic chest pain

Repeated episodes can lead to compromised lung function, pulmonary hypertension and respiratory failure.

Airway hyper reactivity !!

Genito urinary

sickling in the vasa recta. Loops of henle damage Priapism

Hepatic

Jaundice Gall stones Liver cell failure due to multiple

infarcts

More common

Skeletal. Sickling and microvascular occlusion within bones and epiphyseal plates often leads to shortening of the limbs and gross deformity of joints. Osteomyelitis may occur.

Skin. Leg ulcers following skin infarcts are common - complicated by trauma and poor hygiene.

Neurological.

"Acute brain syndrome" is rare but serious. It is characterised by confusion with variable neurological defects.

Whilst most resolve spontaneously permanent damage can occur.

There is an increased incidence of subarachnoid haemorrhage, blindness and deafness, neuropathy

Diagnosis

hemoglobin (Hb) electrophoresis will confirm the diagnosis and provide the percentage of abnormal HbS.

prevalence of HbSS is 1:625 (0.2%)

Anaesthetic considerations cholecystectomy, splenectomy, dilation and

curettage, caesarean section, hysterectomy, tonsillectomy and

adenoidectomy, myringotomy, and orthopedic prosthetic surgery

were the most frequently performed

procedures 18 and 16.5 % events

No urgency for the knife

Sometimes a crisis may mimic acute abdomen

Have they taken h influenza and pneumovac

Investigations

Chest radiograph, hemoglobin oxygen

saturation, and lung function tests may delineate the degree of pulmonary pathology

Bad xray – bad post op course

Blood grouping and transfusion history

Examine kidney and brain

assessment of renal pathology SSD – low BP But if we have high BP look for renal

parameters Psychiatric problems, seizures, poor

school performance, developmental retardation may be markers of insidious neurologic vascular damage and cerebral infarction

Investigations

Hb, blood microscopy to check for sickle cells, Howell Jolly bodies and sideroblasts, all features of the disease. TC DC

ECG Rt dominance Urine for occult infections LFT – unconjugated bilirubin due to

hemolytic anemia Cholestasis evidence

Preop

correct infections Correct dehydration Anemia Preop HbA should be more than 40 % Earlier they said it was 70 % Preoperative physiotherapy and

breathing exercises

Specific procedures

Chole OBG Ortho Neuro CPB

Aims

perioperatively. avoid hypoxia, acidosis, hypotension, dehydration and hypothermia

Principles GA Good intravenous access for maintenance of

intravascular volume Adequate oxygenation Endotracheal intubation for general

anesthesia to ensure a controlled airway and adequate ventilation

Maintenance of adequate oxygen-carrying capacity through judicious use of red cell transfusions

Maintenance of normothermia Opioids for analgesia carefully titrated for

perioperative and postoperative analgesia Avoidance of tourniquet use ??

Monitoring

Pulse oximetry NIBP, temperature Blood loss CVP Urine output ECG Position of the patient

Co morbid conditions

Lungs CVS Renal Hepatic

Regional anaesthesia Drugs – less No problem about lungs liver etc. Vasodilation and less vaso occlusive

crisis Early post op analgesia But No adrenaline Regional blocks may cause

hypotension and hypoperfusion Skeletal abnormalities may confound

Post op

The postoperative complications most likely to occur in the sickle cell disease (SCD)

patient include vaso-occlusive crisis (VOC), pulmonary infarction, acute chest syndrome

(ACS), and infection.

Sickle cell crisis- types acute clinical picture generally caused by

sickling of red blood cells in the microcirculation.

Vascular occlusion crises with organ infarction , pain

Hemolytic crises with hematologic features of sudden hemolysis ( associated with G6PD disease)

Sequestration syndrome with sequestration of red blood cells in the liver and spleen causing their massive, sudden enlargement, and an acute fall in peripheral hematocrit.

Aplastic crises with bone marrow suppression

obstruct capillaries and restrict blood flow to an organ, resulting in ischaemia, pain, necrosis and often organ damage

common in patients with co-existent G6PD deficiency

This autosplenectomy increases the risk of infection from encapsulated organisms

triggered by parvovirus B19, which directly affects erythropoiesis

Sickle cell crisis

Bed rest Hydration Oxygen therapy Treatment of infection Analgesics (consider patient-controlled

analgesia) Consider regional analgesia Transfusion to reduce the HbS concentration Incentive spirometry Maintenance of normothermia

Newer modalities

Exchange transfusion Hydroxy urea – stimulates Hb

F production Inhaled nitric oxide

Of no benefit ??

Alkalization using magnesium glutamate or sodium bicarbonate in an attempt to increase oxygen affinity to haemoglobin in the red blood cell.

Antiplatelet and anticoagulants to reduce infarction.

Hyperbaric oxygen, high concentration oxygen therapy.

The basis of sickle cell

the fundamental of management remains meticulous observation and vigilance of the basic principles of safe anesthesia

Summary

HbSS Preop – hydration, O2 and end

organs Intra op – hydration, temp, O2, CO2 ,

assess end organs Post op pain relief Previously it was sickling alone Now it is sticking also

Thank you all