CASE PRESENTATION BY; DR NUR AIZA IDRIS MODERATOR: DR NORASLAWATI
CASE PRESENTATION• 4 years old boy• Known case of – Hemophilia A (diagnosed since born, on occasional factor VIII transfusion , last transfusion was in April 2011) – HbE/ Beta- thalasemia trait (last blood transfusion was in April 2011) – Under Blood Bank HSNZ follow up
• Positive family history of thalasemia and hemophilia.(His brother also had been diagnosed to have hemophilia and thalasemia + mother is thalasemia trait and hemophilia trait)• Previously he had multiple admission to hospital due to UGIB and recurrent adenotonsillitis with no obstructive symptoms.• He was electively plan for adenotonsillectomy for recurrent adenotonsillitis by ORL team after they seen him in the clinic.
• Patient was seen at anaesthetic clinic for preoperative assessment.• Patient was alert, comfortable. Lungs and CVS examination revealed no abnormality. Liver and spleen was just palpable. His airway was normal. He was classified as ASA 2.• The investigation results were: HB 8.8 TWBC 9 PLATELET 365 APTT 106.6 INR 1.13 PT 13.5
• The anaesthetic plan were: – Technique of anaesthesia: GA with IPPV – To repeat FBC and coagulation profile on admission – To confirm factor VIII prior op with blood bank – To discuss with blood bank regarding timing for factor VIII transfusion prior op – Aim hb>8 g/dl
• The day before operation, he was seen again by anaest MO for preoperative evaluation. No new complaint. His investigation results were: HB 8.1 TWBC 7.5 PLATELET 302 APTT NULL INR 0.99 PT 13.5• Case was noted to the specialist incharge. Syrup phenergen 5mls ON and when OT call was ordered for premedication. Blood bank was also informed .
• On the day of op, patient was alert and comfortable.• BP was 104/71 with pulse rate 110.• Patient was induced with – IV fentanyl 15mcg – Iv propofol 40mg – IV rocuronium 8mg• Intubation done using ETT size 4.5mm. CL grade 2 and it was uneventful.
• 2 vial of Factor VIII was transfused 30min prior to op.• Intraoperative finding was: – Adenoid enlarged – curettage done – Tonsil 2+/2+ - removal done – Estimated blood loss was minimal• Able to extubate well. Breathing effort was good. No stridor noted post extubation.• After 30min observed in recovery room , patient was discharged to ward.• Another 1 vial of Factor VIII was transfused post operatively and was planned for 8 hourly transfusion for 3 days.
• D2 post adenotonsillectomy, patient developed stridor and occasional tachypnea. On examination revealed huge blood clot in his mouth and patient was unable to expel it.• Emergency exploration under GA was planned. Case was notified to GA oncall and discussion with blood bank was done.• Factor VIII infusion 250IU was given 2 vials preop with expected coverage 70%-100%.• Random FVIII assay was send.• He was planned for another factor VIII infusion and iv tranexemic acid post operatively.
• Preoperative assessment was done in OT. On examination, patient was alert and conscious. Not in respiratory distress .There was old blood noted from both nostrils. No active bleeding seen from oral cavity. Lungs examination showed good and equal air entry. Hemodynamically stable.• Case was reviewed in OT with specialist on call and planned to proceed op with ICU back up post op.
• Investigation results were: Hemoglobin 11.0 TWBC 12.0 Platelet 199 Factor VIII assay 20%• GSH was converted to GXM.
• Patient was induced with – IV fentanyl 15mcg – Iv propofol 30mg – IV scoline 15mg• Intubation done using ETT size 4.5mm anchored at 14cm and it was uneventful.• Intraoperatively, hemodynamically stable.• Findings were: – Big blood clot at superior pole of right tonsil bed – Blood clot at lower pole of left tonsil bed – Both obstructed the airway – Removal of blood clot done – minimal bleeding present and was secured. – EBL: minimal
• Post operatively, able to extubate patient. No active bleeding from mouth.• Post extubation, noted noisy breathing. Decided to admit ICU for close observation.• Factor VIII infusion 250 IU was given immediately post op (as planned before)• Then, he was admitted to ICU for close observation. Oxygen therapy given at 3L/min. Patient was kept nil by mouth with IVD maintenance at 48mls/H. Planned for reintubation if patient developed worsening respiratory distress.
• In ICU, factor VIII infusion 250 IU was continued as planned (given 8 hourly). IV tranexemic acid was given for 1 day.• Factor VIII assay was repeated and the result was 60%.• After 1 day in ICU, condition improved and he was transferred to general ward .• Day 3 post exploration, blood clot evacuation and hemostasis ; patient again had bleeding from nose and oral cavity.
• Factor VIII infusion 2 vial was given stat and continued for 6 hourly. Factor VIII assay and PT/APPT mixing (for inhibitor screening) was sent immediately.• Re-exploration was done as emergency. Novo seven was standby and planned to wean in ICU post operatively. Parents were informed regarding difficult intubation and post op ventilation in ICU.• During intubation , noted huge blood clot obscuring the vocal cord and at peritonsillar area. However, intubation was uneventful.
• Intra-operative findings was: – Both tonsilar bed full with blood clots and debris ; removed with forcep – Multiple bleeding sites from raw areas – EBL : 50mls – Novoseven 1 vial was given intra-operatively.• Post op, patient was transferred to ICU for weaning as planned. Infusion factor VIII was continued 6 hourly.• Since hemostasis not secured despite good factor VIII coverage , development of fVIII inhibitor is suspected. APTT/mixing test, factor VIII assay and inhibitory assay were sent immediately.
• The results were: Investigations 5/6/11 6/6/11 Hb 9.8 5.7 Twbc 12.3 6.7 Platelet 361 249 APTT-mixing test 43.2 Factor VIII assay 1% 1% Inhibitory assay 8.5 bethesda unit• Impression was : Hemophilia A with inhibitor
• Day 2 post re-exploration, EUA done.• Findings:• IV Novoseven given intraoperatively.• Patient able to extubate post-op. and was sent to ICU for close observation.• His condition improved and T/O to general ward after 8 hours observation.
Problem – based learning• Medical disease (basic)• Preoperative evaluation and preparation• Intraoperative Management• Postoperative Management
Medical disease (basic)1. What are the differences between hemophilia A, B, and C?2. Describe the physiologic events that occur following endothelial interruption in the blood vessel.3. What prevents the extension of a clot beyond the site of injury?4. Describe extrinsic, intrinsic, and common coagulation cascade.
Preoperative evaluation and preparation1. What should you ask in history taking?2. Describe the various laboratory tests that evaluate the coagulation cascade and the specific components measured by each.3. Describe the levels of factor VIII necessary for hemostasis.4. What is meant by one unit of factor VIII clotting activity and how much does one unit of factor VIII clotting activity per kilogram of body weight increase factor VIII concentration?5. How much factor VIII activity is present in fresh frozen plasma (FFP)? What are the risks associated with administration of FFP?
6. How is cryoprecipitate prepared? What are the components in cryoprecipitate? How much factor VIII activity is present in cryoprecipitate? What are the indications for cryoprecipitate?7. What is the role of desmopressin (DDAVP) for hemostatic management in hemophiliac patient?8. What is the role of tranxenamic acid in the perioperative period for the hemophiliac patient?
Intraoperative Management1. Is it safe to administer an intramuscular (IM) injection to patient before surgery?2. Would it be safe to intubate the patients trachea?3. What special considerations should be taken in choosing anesthetic drugs for this patient?4. Does giving blood intraoperatively increase the potential for the development of factor VIII inhibitors?5. Can factor VIII be safely administered to patients who have developed circulating inhibitors?6. Is it appropriate to suction the endotracheal tube and oropharynx of this patient before extubation?
Postoperative Management1. What special consideration should be given to postoperative pain management for this patient?2. What is recommendation for plasma factor levels and duration of replacement to prevent post op bleeding?
Hemophilia A• factor VIII deficiency• the most common form, accounting for 85% of all patients with hemophilia.• It is an X-linked, recessive disorderHemophilia B• deficient or defective factor IX• this entity represents 14% of hemophilia patients.• This X-linked, genetic disorderHemophilia C• deficiency in factor XI• an autosomal disorder
The severity of bleeding manifestations in hemophilia is generally correlated with the clotting factor level as shown in the following table.
exposes platelets to glycoprotein receptors subendothelial on the platelets to endothelial break structures (collagens rapidly adhere to and other activating these substances. proteins) shape of the platelet is changed and theFormation of platelet stimulate platelet contents of the plug aggregation cytoplasmic granule are released (ADP)interaction with both Activation of factor fibrin and thrombin XIII produces crossfuse the platelet plug polymerization of the for continued loose fibrin to produce hemostasis a firm clot.
• Localization of coagulation and control of primary hemostasis are controlled by many factors, including the dynamic tension between two prostaglandins, thromboxane A2 and prostacyclin.• Thromboxane A2 is released at the site of vascular injury and stimulates vasoconstriction, ADP release, and platelet aggregation.• In contrast, prostacyclin is produced by intact endothelial cells and prevents platelet aggregation and clot formation.• In addition, clot localization is maintained by the dilution of procoagulants flowing in the blood, the removal of activated factors by the liver, the action of circulating procoagulant inhibitors such as antithrombin III and protein C, and the release of the serine protease tissue plasminogen activator (TPA).• TPA digests fibrinogen as well as factors V and VIII, initiating the physiologic process of fibrinolysis and resulting in fibrin degradation (split) products, which are removed by the mononuclear phagocyte system.
Elicit the age of onset and symptoms of coagulation disorderObtain a family history of bleeding disordersDetermine hemostatic reponses to previous procedures;anyexcessive bleeding and need for blood transfusionDrug historyAssociated medical conditions
Specific Components Measured by Different Coagulation Tests LABORATORY TESTS COMPONENTS MEASURED Bleeding time Platelet count, vascular integrity Prothrombin time I, II, V, VII, and X (extrinsic pathway)Partial thromboplastin time (PTT) I, II, V, VII, IX, X, XI, and XII (intrinsic pathway) Thrombin time I, II
• The levels of factor VIII necessary for hemostasis are described in the table below. When life-threatening airway or neurologic bleeding has occurred, factor VIII level of 100% should be achieved. Similarly when major surgery is anticipated, correction to 100% factor VIII level should be done preoperatively and maintained postoperatively The Levels of Factor VIII Necessary for Hemostasis CLINICAL PRESENTATION FACTOR VIII CONCENTRATION (% OF NORMAL) Spontaneous hemorrhage 1–3% Moderate trauma 4–8% Hemarthrosis and deep skeletal muscle hemorrhage 10–15% Major surgery Greater than 30%
One unit of factor VIII:C clotting activity is defined asthe amount present in 1 mL of fresh normal, pooledplasma.A single unit of factor VIII clotting activity per kilogramof body weight will increase plasma factor VIII levelsapproximately 2%.Prescribe the factor VIII activity necessary to correct a70-kg hemophilia patient with 5% factor VIII activity to95% of normal
FFP contains all plasma proteins, including factorVIIIFactor VIII activity : 0.7 to 0.9 unit of clottingactivity per mL FFPrisks associated with the transfusion of FFP• similar to any other single-donor blood product i.e HIV or hepatitis viral transmission
Cryoprecipitate is the fraction of plasma thatprecipitates when FFP is thawed.Contains: factor VIII, factor VIII: von Willebrandsfactor, factor XIII, and fibrinogenFactor VIII activity : 5 and 13 units of factor VIIIclotting activity per mL cryoprecipitateIndication : hemophilia, von Willebrands disease,hypofibrinogenemia, uremic platelet dysfunction
• This synthetic analog of the antidiuretic hormone is used to prepare mild and moderate hemophiliacs for minor surgery.• Intravenous DDAVP will rapidly release preformed factor VIII complex, which leads to a two- to threefold increase in circulating factor VIII within 30 to 60 minutes of administration. In addition, factor VIII:C and von Willebrands factor are released from the endothelial cells.• In a patient with mild or moderate hemophilia A or von Willebrands disease, this influx of factor VIII may provide adequate hemostasis for minor elective surgical procedures.• The half time of this released factor is approximately 12 hours and repeated administration of DDAVP will deplete the storage capacity in the endothelial cells.
antifibrinolytic agent that competitivelyinhibits the activation of plasminogen toplasmin.promotes clot stability and is useful asadjunctive therapy in hemophilia and someother bleeding disorders.
• IM injections can be safely administered to any patient with a factor VIII activity greater than 30%.• Therefore, if appropriate factor VIII correction has occurred before surgery, an IM injection would be considered safe.• However, it is best to avoid and would be prudent to use an intravenous route.
unique challenge for the anesthesiologist because of therisk of hemorrhage in the tongue or neck, which couldcompletely compromise the upper airway of the patientmanipulation of the airway during intubation should notbe performed until appropriate replacement factorshave been administered.Care should be used in placing the mask on the patientto avoid trauma to the lips, tongue, or facelaryngoscopy should only be attempted followingpreoperative factor correction and achievement ofcomplete muscle relaxationnasal intubation should be avoided
• Coexisting liver disease is a common complication in the hemophiliac patient because of hepatitis acquired from previous blood or factor transfusions.• As a result, drugs that are metabolized by the liver should be used with caution in the hemophiliac patient.• A balanced intravenous technique might be preferable to an inhaled anesthetic because of the reduced hepatic blood flow observed in an inhaled technique.
• Although 10% to 15% of all hemophiliac patients will develop a circulating inhibitor of factor VIII, there is no evidence that the development of such an inhibitor is related to the number of transfusions that the patient receives.• As a result, the administration of blood products in this setting should not be withheld for fear of inducing an inhibitor response
• Occasionally hemophiliac patients develop IgG antibodies to the deficient factor.• The inhibitors may be of low titer and transient or of extremely high titer and very persistent.• The Bethesda unit of inhibition is defined as the amount of inhibitory activity in 1 mL of plasma that decreases the factor VIII level in 1 mL of normal plasma from 1 to 0.5 units.• It is almost impossible to overpower a high-titer inhibitor, but, when life-threatening hemorrhage occurs, massive doses of factor VIII concentrates or plasmaphoresis with replacement of factor VIII should be given and may be of temporary benefit.• Replacement with large amounts of factor VIII concentrate may provide temporary hemostasis but will stimulate an increase in the antibody titer.
• Porcine factor VIII is effective in hemophilia A patients with inhibitors. The porcine factor VIII provides adequate factor VIII activity in patients with less than 50 Bethesda units of inhibitor.• Porcine factor VIII may provide hemostasis because of its distinct antigenicity, even in the presence of circulating inhibitor.• Immunosuppressive therapy is of no value.• Alternative approaches to therapy of the hemophilic patient with inhibitors involve the use of other agents such as activated prothrombin complex concentrated (APCC), which contain activated vitamin K dependent enzymes as well as recombined factor VIIa.• These activated coagulants enter the coagulation cascade distal to the level of factor VIII and, therefore, bypass the effects of the inhibitor. Thrombosis is a possible complication.
• Removal of secretions that might be aspirated is essential before the extubation of any patient.• However, suctioning of the oropharynx of hemophiliac patient can trap mucosa in the suction catheter and result in the formation of an oral hematoma.• In a hemophiliac patient, gentle oral suctioning under direct vision is appropriate to remove all secretions
Avoid any postoperative pain supplements that mightproduce a bleeding diathesis in the hemophiliac patient.Analgesics containing aspirin or nonsteroidalantiinflammatory drugs (NSAIDs) should be avoided.Antihistamines and antitussives can inhibit plateletaggregation and prolong bleeding time.Narcotic analgesics or acetaminophen-based productsshould be appropriately titrated for postoperative painmanagement.
PART 2 – ANAESTHESIA AND POST TONSILLECTOMY BLEEDING
CASE SCENARIO• You have been called to see a 5-year-old child who had a tonsillectomy six hours previously. The child is bleeding and needs to go back to theatre for haemostasis. When you arrive on the ward the child is agitated and says he feels sick. The postoperative blood-loss is reported to be minimal by the nursing staff.• On examination he is pale. His pulse is 125/min, respiratory rate is 25/min, blood pressure 80/40mmHg and capillary refill time 4 seconds. Stridor was heard. Patient is using his accessory muscle to breath. His saturation maintain at 95-100%.
Questions1. What are the specific problems in this case?2. What are the causes of postoperative stridor?3. How do you assess hypovolemia in children?4. What is the immediate management in the ward?5. How would you induce this patient and what drugs would you use?6. Upon arrival at GOT, the stridor does not resolved and there is falling SpO2 ; what should you do?
What are the specific problems in this case?HypovolaemiaDifficult intubation (bleeding, laryngeal oedema)Aspiration (blood/food)Second general anaestheticManagement of an anxious child/parents
Causes of postoperative stridorLaryngospasmParalysis of one or both vocal cordsLaryngeal edemaExtrinsic or intrinsic compression of the airwayPresence of mass, fluid or blood in the airwayCongenital or acquired airway pathologyResidual effect of anaesthetic agents
How would you assess hypovolemia? • tachycardia Cardiovascular • low blood pressure • prolonged (>2secs) capillary refill time • cold Skin • mottled skin • agitation , confusion Cerebral • drowsiness • depressed conscious level Renal • low or absent urine output. • Tachypnoea then acidotic sighing Respiratory respirations. • low haemoglobin Laboratory • metabolic acidosis • high blood lactate.
The immediate management • Maintain the airway and support ventilation Aim • to treat hypovolemia without delaying transfer to theatre for haemostasis1. High flow oxygen via facemask if the child tolerates (10-15 L/min)2. Apply standard airway support using chin lift or jaw thrust3. Assess for respiratory distress4. Assist ventilation with continuous positive airway pressure5. Assess volume status6. Obtain intravenous access7. Send for full blood count, cross match and coagulation.8. Resuscitate with intravenous fluids and blood products as needed9. Prepare for theatre10. Call for senior help11. Closely monitor the saturation and review the hemodynamic status
Induction• Post-tonsillectomy hemorrhage patients must be considered to have a full stomach given an unknown but potentially large amount of blood may be swallowed.• Adequate fluid resuscitation prior to induction is critical. This can be performed in the emergency department, the surgical holding area, or even in the operating room prior to anesthesia.• Anesthetic management should entail a rapid sequence induction with cricoid pressure followed by evacuation of gastric contents.• The choice of induction drug should be based on the patient’s volume status and hemodynamic stability.
• If the volume status is deemed borderline or there is rapid ongoing blood loss, etomidate is a good choice.• While ketamine may also be safe, remember that myocardial depression and hypotension can still be seen in the hypovolemic patient.• The adequately resuscitated patient will likely tolerate propofol or a barbiturate.• The neuromuscular blockers that give the best intubating conditions in less than 60-90 seconds would be succinylcholine or rocuronium, however rocuronium may result in paralysis outlasting the surgical procedure.
• Call for help• Ask for difficult intubation trolley• Prepare for emergency re-intubation• Use a smaller sized ETT in case of laryngeal edema• Remember that LMA may not overcome airway obstruction if it occurs at the glottic or subglottic level• If tracheal intubation is difficult and SpO2 remains low , perform an immediate cricothyrotomy and begin transtracheal jet ventilation.