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Haemoglobinopathies thalassemia, prophyrias and sickle cell disease-


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Haemoglobinopathies and anaesthetic management

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Haemoglobinopathies thalassemia, prophyrias and sickle cell disease-

  1. 1.   Moderator: Dr. Satish Speaker: Dr. Deepa
  2. 2. The hazards of surgery in these patients are not always those which are attendant on conditions suggesting emergency surgery. . .The presence of the basic disease increases the hazard of surgery, and of course, of anesthesia. —In ANESTHESIOLOGY, 1955
  3. 3. Haemoglobinopathies are diseases involving abnormalities of the structure or production of haemoglobin
  4. 4. Haemoglobin is a tetrameric protein consisting of two alpha (a) and two nonalpha polypeptide chains attached to four iron-containing heme complexes.
  5. 5. An autosomal recessively inherited disorder of the β- haemoglobin chain caused by substitution of Valin for Glutamic Acid in β-globin subunit. This disease is characterized by  Haemolytic anaemia,  Intermittent vaso occlusive crises  Variable phenotypic expression.
  6. 6.  Hb S gene is found primarily in populations of native tropical African origin  Sickle cell disease (SCD) refers to a group of haemoglobinopathies. - HbSS – Sickle cell anaemia - HbSC disease - HbSD disease - HbS/β-thal - Sickle β-thalassemia
  7. 7. Pathology: - HbS polymerization depends upon the haemoglobin concentration per cell, i.e. high MCHC. - Decreased pH reduces the oxygen affinity to Oxygen, thereby increasing deoxygenated Hb and increasing sickling - Duration of Red cell exposed to low oxygen
  8. 8.  Cellular response of haemoglobin S is due to both unstability and insolubility of HbS as a result of the loss of the negative charge resulting in stickling and sickling during extreme state of deoxygenating by aggregation and polymerization
  9. 9. Also known as Pain crisis is the hallmark of SCD, represent episodes of hypoxia injury and infraction associated with severe pain in the affected region triggered by infection, dehydration and acidosis.
  10. 10. Neurological  Pain crisis Occurs in 70% of patients  Stroke 10% of children; subclinical microvascular occlusion in more than 20%. Cause of 20% deaths.  Peripheral neuropathy unusual complication  Chronic pain syndrome in a small subset of patients
  11. 11.  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
  12. 12. Pulmonary  Acute Chest Syndrome Occurs in 40% of patients; mortality rate of 1.1% for children and 4.8% for adults.  Airway hyperreactivity 35% of children  Restrictive lung disease 10–15% of patients
  13. 13. Genitourinary  Nocturnal enuresis not a sensitive predictor  Chronic renal insufficiency Present in 5–20% of adults  Urinary tract infection Increased incidence; may trigger ACS  Priapism 10–40% of men
  14. 14. Sickle cell nephropathy, characterised by  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.  UTI and pyelonephritis due to structural abnormalities and scarring.
  15. 15. Gastrointestinal  Cholelithiasis Up to 70% of adults  Liver disease: Viral hepatitis from transfusion in up to 10% of adults. Liver failure 2%.  Dyspepsia Mucosal ischemia, rather than increased acid production, is thought to be the cause.  Reflux is not a complication of SCD.
  16. 16. Haematological  Haemolytic anaemia Typical baseline haemoglobin levels are 6–9 g/dl in SS disease, higher in SC disease and Arab phenotype.  Acute aplastic anaemia Parvovirus B19 infections trigger acute severe exacerbations of anaemia  Splenic enlargement/fibrosis Less affected: SC disease, Arab haplotype
  17. 17. Orthopaedic  Osteonecrosis Up to 50% of adults  Osteomyelitis Salmonella and Staphylococcus aureus are commonest pathogens.  Dactylitis Early onset is a marker of disease severity Vascular  Leg ulcers
  18. 18. Immunological  Immune dysfunction Increased susceptibility to infections  Erythrocyte auto/alloimmunization Increased incidence of transfusion  Haemolytic transfusion reactions Alloimmunization
  19. 19.  Although sickle cell trait does not cause a marked increase in perioperative morbidity or mortality. Management of SCD focuses on controlling symptoms and minimizing crises.  SCD-specific complications, or “sickle events,” include - Pain crisis - ACS
  20. 20. Complications include: Increased incidence of erythrocyte alloimmunization and transfusion reactions consequent on perioperative transfusion
  21. 21. Nonspecific complications include  Fever  Infection  Bleeding  Thrombosis  Embolism  Death from causes other than SCD
  22. 22. Preoperative:  History and examination- Establish organ damage, risk factors  Investigations: Investigations as indicated by patient and procedure  Consider prophylactic transfusion: Transfusion Crossmatch for Rhesus, Kell, and Lewis antigens, alloantibodies
  23. 23. Predictors of Postoperative SCD complications  Type of surgical procedure-Low, moderate or high risk  Increased age-Associated with disease progression  Frequency of recent complications-Current activity of disease state  Hospitalization-Marker of disease severity  Temporal clustering of ACS-Progression of lung disease  Abnormal lung fields on radiograph-Evidence of sickle chronic lung disease  Pregnancy-Increased risk of maternal complications  Pre-existing infection-Triggering agent for ACS  Haplotype-African haplotypes have more severe disease than the Asian haplotype
  24. 24. Intraoperative  Hydration: Modify according to renal pathology  Oxygenation : Modify according to organ pathology  Thermoregulation: Normothermia; hypothermia if indicated under deep anaesthesia. Normothermia maintenance.  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.  Transfusion: As indicated by haemorrhage and organ pathology  Aesthetic technique As indicated by procedure
  25. 25.  Use of a tourniquet (depending on surgery planned) is controversial in both the homo- and heterozygote during surgery to prevent stasis of blood. - If essential ensure careful wrapping of extremity, normothermia, short compression time, hyperoxygenation
  26. 26. Prevent sickling by avoiding  Hypoxaemia  By measuring oxygen saturation using pulse oximetry and giving prophylactic oxygen.  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
  27. 27.  Hyperviscosity  Keep Hb around 10 gdl-1  Maintain hydration  Acidosis  Positive pressure ventilation during surgery to achieve normocarbia and avoid acidosis.  Aim for mild respiratory alkalosis (pH ≈ 7.45)
  28. 28.  To avoid dehydration (i.e. to prevent circulatory stasis)  An IV infusion should always be set up pre-operatively.  Allow oral fluids as late as possible and give pre- and post-operative IV fluids
  29. 29. Postoperative  Basic care : Early mobilization, pulmonary toilet, effective analgesia  Supplemental oxygen as required Pain crisis: Pain scoring Early effective analgesia—opioids  Adjuvant analgesics—nonsteroidal anti-inflammatory drugs, acetaminophen  Consider regional analgesia, incentive spirometry  Pulmonary monitoring  Psychological support
  30. 30.  ACS is typically detected 2–3 days postoperatively.  Difficult to diagnose but common characteristics: - fever, dyspnoea, cough, chest pain and pulmonary infiltrates  Pneumonia can trigger and complicate ACS, broad-spectrum 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
  31. 31. Pre-op measures to reduce risk of ACS:  Transfusion  Aims to increase HbS level to ≈30% and haemoglobin >10g/dl before major surgery. The need to reduce HbS to these levels has recently been questioned  Hydroxyurea  Enhances formation of HbF  Lung function tests to assess respiratory fitness.
  32. 32.  Controversial areas in managing patients with sickle cell disease.  Past history of frequent complications, increased tissue oxygenation, reduced blood viscosity, and a "margin of safety".  Disadvantages include induction of hyperviscosity, significant alloimmunization, delayed transfusion reactions, exposure to infectious disease, cost, and provision of a false sense of security.
  33. 33.  A recent cooperative study of preoperative transfusion demonstrates that sickle cell patients should have simple transfusions to raise the patient's haemoglobin to 10 gm/dL before surgery.  safer and as effective in preventing postoperative complications as are exchange or aggressive transfusions to decrease the haemoglobin S level below 30%  Postoperative complications such as chest syndrome, fever, and alloimmunization with delayed transfusion reactions are common
  34. 34.  Autosomal recessive disorder of haemoglobin that results in haemolytic anaemia  Frequently encountered in people of Mediterranean or South Asian ancestry  Occurs because of a disruption of the normal 1:1 ratio of α– and β-chains.  There are multiple forms of thalassemias. Imbalance of α– and β–chains results in rapid erythrocyte destruction and turnover with a chronic haemolytic anaemia
  35. 35.  Inheritance of thalassemia mutations with haemoglobin S will produce a sickle-thal disease very similar to sickle cell anaemia.
  36. 36.  Alpha thalassemia is characterized by the deficiency or deletion of alpha–chains  Beta thalassemia is caused by reduced or absent synthesis of beta-chains
  37. 37. Types of Alpha Thalassemia:  Alpha thalassemia major, also called haemoglobin Bart’s, occurs when 4 alpha–chains are replaced by gamma-chains; this results in hydrops fetalis syndrome.  Absence of 3 alpha–chains results in alpha-thalassemia intermedia which has four beta-chains and haemolytic anaemia. These excess beta-chains form unstable tetramers called haemoglobin H with abnormal oxygen dissociation curves.
  38. 38.  When 2 alpha–chains are involved, the patients have alpha thalassemia minor and a mild anaemia; a single alpha–chain involvement results in the alpha thalassemia carrier state
  39. 39.  Types of Beta Thalassemia: a) Beta Thalassemia Minor: Single gene defect. Patients are asymptomatic and have mild anaemia. b) Beta thalassemia intermedia is intermediate between minor and major; patients require only occasionally require transfusions
  40. 40. c) Beta-thalassemia major is also known as Cooley’s anaemia and involves the absence of 4 beta–chain production.  Severe haemolytic anaemia,  Poor growth,  Skeletal abnormalities,  Hepatosplenomegaly, jaundice  Vascular damage  These children require lifelong transfusion and the life may be foreshortened by the cardiac complications of iron overload.
  41. 41. Investigation:  CBC with differential count, peripheral smear for schistocytes, reticulocyte count, PT/PTT, LFTs, metabolic profile, TSH, iron, TIBC, folate, ferritin, B12, transferrin, blood type/screen, ESR, CRP, lactate, DIC panel, haptoglobin, LDH.  Serum iron level is unreliable, with ~78% sensitivity and 36% specificity in ICU management.  Reticulocyte index  Iron levels and other serum studies may be inaccurate if recent transfusions have been given.
  42. 42.  Urine analysis, creatinine, BUN, glucose  CPK and troponin (for rhabdomyolysis and ongoing ischemia from anaemia)  CXR, EKG, ABG, SvO2  Low MCV with high reticulocyte count may be the first indirect evidence for thalassemia
  43. 43.  Serum iron studies: High, with extremely elevated saturation levels, >70-80%; TIBC elevated Ferritin: High, but levels need to be taken into consideration in face of acute illness. Some patients may have iron overload.  Peripheral smear: Usually done by automated systems in lab, but ask for specific haemolysis and anaemia profiling. Great source for identification of abnormal cell types, inclusion bodies (Heinz), morphology
  44. 44.  Severity of Thalassemia is critical determinant.  Chronic anaemia is major concern.  Bony malformations that may disturb tracheal intubation  Complications of Iron over load leading to cirrhosis, right sided heart failure and endocrinopathies.
  45. 45. A group of inherited or acquired enzymatic defects of home biosynthesis.  Each type of porphyria has a characteristic pattern of overproduction and accumulation of home precursors based upon the location of the dysfunctional enzyme in the home synthetic pathway.
  46. 46.  Acute Intermittent Porphyria (AIP),  Variegate Porphyria (VP),  Hereditary Coproporphyria (HCP)  and the very rare Plumboporphyria (PP).  With the exception of PP, which is recessive, these porphyrias are inherited as non‐sex‐linked, autosomal dominant conditions with variable expression
  47. 47. a) Acute Intermittent Porphyria: The defective enzyme in this condition is porphobilinogen deaminase and the gene encoding this enzyme is located on chromosome 11. PBG deaminase deficiency can, in most cases, be detected in red cells between attacks.  the most severe symptoms, and is the one in which an acute attack is most likely to be fatal  hypertension and impaired renal function are significantly more common in porphyric subjects
  48. 48. b) Variegate porphyria: This condition is characterized by cutaneous photosensitivity in which bullous skin eruptions occur on exposure to sunlight as a result of the conversion of porphyrinogens to porphyrins.  The characteristic skin lesion is one of excessive fragility, especially on sun‐exposed surfaces such as the face and hands, where bullae and erosions with subsequent pigmented ‘tissue paper’ scarring are frequently seen.
  49. 49.  The enzyme defect is at the level of protoporphyrinogen oxidase but there is also a reduced amount of PBG deaminase.  The gene encoding this enzyme is on chromosome 1. The incidence of VP in South Africa is the highest in the world.
  50. 50. c) Hereditary coproporphyria: This condition is far less common than VP and AIP. Acute attacks appear to be considerably less severe, and the prognosis better. The defective enzyme is coproporphyrinogen oxidase, encoded by a gene on chromosome 9. As in VP, cutaneous photosensitivity is characteristic, though it tends to be less severe in the interval between acute attacks than it is in VP.
  51. 51. d) Plumboporphyria: This, the rarest of the acute porphyrias, results from a deficiency of ALA dehydratase, which is encoded by a gene on chromosome 9. It is associated with an excess of urinary ALA analogous to that found in lead poisoning (hence the name), although lead concentrations in the blood are normal. Unlike the other acute porphyrias, the mutation is recessive, and the disease presents early in life, with all clinically manifest cases being homozygotes. No references to anaesthesia for patients with this condition have been published
  52. 52. Classical case presents with colicky abdominal pain, muscular weakness, paralysis, psychiatric manifestations, and red coloured urine. Insomnia is a frequent symptom and may lead to the administration of barbiturates and a subsequent precipitation of an attack
  53. 53. Acute Abdomen and porphyria : The following symptoms should raise suspicion of porphyria in patients with  acute abdominal pain: mental status changes (confusion, hysteria),  peripheral neuropathy (motor > sensory), dark coloured (red to purple) urine, and known family  History of porphyria. Of special concern is the parturient with acute abdominal pain. Greater than 50% of pregnant women who have porphyria will experience a crisis during pregnancy or puerperium, probably due to ALA sythetase induction by hormonal changes of pregnancy. If the patient with an acute abdomen, pregnant or not, does not have suggestive symptoms of porphyria, anaesthetic drugs and therapies should not be modified
  54. 54. Known acute porphyria : In the setting of known acute porphyria, perhaps the most difficult situation is when an acute attack is caused by and is concurrent with a disease process which mandates surgical intervention; i.e. the infection, pyrexia, and anorexia of acute appendicitis inducing ALA sythetase and precipitating crisis.  Neurologic evaluation should focus on mental status and peripheral neuropathy. If an  acute crisis is suspected, attention to cranial dysfunction and bulbar symptomatology may  predict impending respiratory failure.
  55. 55.  Premedication is important, as psychological stress alone has been reported to precipitate crises.  Numerous reports have implicated benzodiazepines, and their use is discussed below. Narcotics are safe in porphyria, with the exception of pentazocine, a partial agonist. Scoplamine and atropine are considered safe. Acceptable non-narcotic sedative include droperidol, promethazine, chloral hydrate, and diphenhydramine
  56. 56.  Most porphyric can be anaesthetized with relative safety provided that appropriate precautions are taken.  Mainstay of the safe anaesthetic management of these patients depends on the detection of susceptible individuals, and the identification of potentially porphyrinogenics agents
  57. 57.  A careful family history should be obtained and a thorough physical examination performed (although there is often no clinical evidence or only subtle skin lesions), and the presence or absence of peripheral neuropathy and autonomic nervous system instability should be noted.
  58. 58.  When a case of porphyria is present, it is important for us to know the factors and agents that precipitate an acute attack. It is also important to choose a drug which will be safe.
  59. 59.  Drugs may trigger acute attack mostly which depends on an increased demand for haem production or a failure of haem inhibitory feedback as the final common pathway.  Drug may induce the transcription of ALA synthetase directly through mRNA or may interfere negative feedback control which haem exerts on ALA synthetase production.
  60. 60.  Drug may interfere with the haem synthetic pathway, thus reducing the level of haem, or may increase the demand by increasing utilization.  Multitude of pathways and variety of drug structures make it impossible to predict prophyrinogenic agent.  The only property of drug that links between porphyria is lipid solubility and membrane fluidization
  61. 61.  Guidelines for drug selection include the following: (1) There is evidence that a single exposure to a potent inducer can be well tolerated, but not during an acute attack. (2) Exposure to multiple potential inducers is more dangerous than exposure to any single agent. (3) Lists of “safe” and “unsafe” anaesthetic drugs and adjuncts may be based on animal or cell culture experiments
  62. 62. Drugs contraindicated in porphyrias  Barbiturates (hepatic porphyrias only)  diazepam  chlordiazepoxide hydrochloride  phenytoin sodium  Sulfonamides  Estrogen  All oral contraceptives  Ergot preparations  methyldopa  Alcohol in any form  pentazocine
  63. 63. INHALED ANESTHETICS  Nitrous oxide- Safe  Isoflurane- Probably safe  Sevoflurane- Probably safe  Desflurane- Probably safe
  64. 64.  INTRAVENOUS ANESTHETICS  Propofol- safe  Ketamine: Probably safe  Thiopental: Avoid  Thiamylal: Avoid  Methohexital: Avoid  Etomidate: Avoid (No proper study is available)
  65. 65. ANALGESICS  Acetaminophen: Safe  Aspirin: Safe  Codeine: Safe  Morphine: Safe  Fentanyl: Safe  Sufentanil: Safe  Ketorolac: Probably avoid  Phenacetin: Probably avoid  Pentazocine: Avoid
  66. 66. NEUROMUSCULAR BLOCKING DRUGS  Succinylcholine: Safe  Pancuronium: Safe  Atracurium: Probably safe  Cisatracurium: Probably safe  Vecuronium: Probably safe  Rocuronium: Probably safe  Mivacurium: Probably safe
  67. 67. OPIOID ANTAGONIST  Naloxone: Safe ANTICHOLINERGICS  Atropine: Safe  Glycopyrrolat: Safe ANTICHOLINESTERASE  Neostigmine Safe
  68. 68. LOCAL ANESTHETICS  Lidocaine: Safe (Theoretically unsafe but no evidence present)  Tetracaine: Safe  Bupivacaine: Safe  Mepivacaine: Safe  Ropivacaine: No data
  69. 69. SEDATIVES AND ANTIEMETICS  Droperidol: Safe  Midazolam: Probably safe  Lorazepam: Probably safe  Cimetidine: Probably safe  Ranitidine: Probably safe  Metoclopramide: Probably safe  Ondansetron: Probably safe
  70. 70. CARDIOVASCULAR DRUGS  Epinephrine: Safe  α-Agonists: Safe  β-Agonists: Safe  β-Antagonists: Safe  Diltiazem: Probably Safe  Nitroprusside: Probably safe  Nifedipine: Avoid
  71. 71. Regional Anaesthesia:  No absolute contraindication  If a regional anaesthetic is being considered, it is essential to perform a neurologic examination before initiating the blockade to minimize the likelihood that worsening of any pre-existing neuropathy.
  72. 72.  Autonomic nervous system blockade induced by the regional anaesthetic could unmask cardiovascular instability, especially in the presence of autonomic neuropathy, hypovolemia, or both.
  73. 73.  Removal of any known triggering factors  Adequate hydration and carbohydrate loading are necessary  Sedation using a phenothiazine  Opioid for pain  Nausea and vomiting are treated with conventional antiemetics.  β-Blockers can be administered to control tachycardia and hypertension
  74. 74.  Since traditional anticonvulsants are regarded as unsafe, seizures may be treated with a benzodiazepine or propofol  Electrolyte disturbances, including hypomagnesaemia, must be treated aggressively.  Administration of home (3 to 4 mg/kg IV daily for 4 days) is indicated after a day or two of the crisis if the patient is no better after receiving conservative therapy. Hemet may be administered as haematin, haem albumin, or haem arginine
  75. 75.  Somatostatin decreases the rate of formation of ALA synthetase and, in combination with plasmapheresis, may effectively decrease pain and induce remission.
  76. 76. 1. Robbins and Cortan Pathologic Basis of Disease 7Th Edition 2. Miller’s Anesthesia 7th Edition 3. Stoelting’s Anesthesia & Co-Existing Disease 5th Edition 4. Br. J. Anasthesia 2000; 85: 143-53 5. Anesthesiology 2004; 101:766–85 Sickle Cell Disease and Anesthesia Paul G. Firth, M.B., Ch.B.,* C. Alvin Head, M.D.†© 2004 American Society of Anesthesiologists