Presentation on theme: "Dr. S. Parthasarathy MD., DA., DNB, MD (Acu), Dip. Diab.DCA, Dip. Software statistics PhD (physio) Mahatma Gandhi medical college and research institute,"— Presentation transcript:
Dr. S. Parthasarathy MD., DA., DNB, MD (Acu), Dip. Diab.DCA, Dip. Software statistics PhD (physio) Mahatma Gandhi medical college and research institute, puducherry – India
What is this? Edward Irons in Noel 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.
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
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 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
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
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