Anesthesia Considerations 

Sickle Cell Disease 

 

 

Considerations 

 

• Multisystem disease with end-organ dysfunction:

  • CNS: stroke

  • Cardiovascular: LV hypertrophy, high-output cardiac failure (anemia), myocardial infarction without coronary artery disease 

  • Respiratory: acute chest syndrome (ACS), restrictive lung disease (pulmonary fibrosis), pulmonary hypertension, RV hypertrophy, cor-pulmonale

  • Renal: renal failure, renal infarction 

  • Spleen: sequestration, infarcts; if splenectomy → ↓ immunity

• Potential for perioperative exacerbations of vaso-occlusive crises:

  • Acute pain crisis

  • Acute chest syndrome

• Chronic hemolytic anemia:

  • ​Chronic RBC transfusion & its complications (alloimmunization, iron overload, viral transmission)

• Chronic pain & potential opioid tolerance

• Preoperative optimization: consider preoperative transfusion for goal hematocrit: 30%, hemoglobin: 100 (see discussion in optimization)

• Medications: immunosuppresants, antineoplastics

 

 

Goals

 

• Avoid precipitants of sickle cell crisis:

  • ​Hypoxia

  • Vascular stasis

  • Hypothermia

  • Hypovolemia/hypotension

  • Acidosis

• Optimize perioperative pain control 

• Monitor for:

  • Vaso-occlusive crisis

  • Acute chest syndrome

  • Aplastic crisis

  • Splenic sequestration syndrome

  • Right upper quadrant syndrome 

 

 

Optimization (in consultation with hematology) 

 

• Risk factors for acute pain crises:

  • Age, frequency of hospitalizations &/or transfusions for episodes of crisis, evidence of organ damage (e.g., low baseline oxygen saturation, elevated creatinine, cardiac dysfunction), history of central nervous system events, concurrent infection

• Procedural risk for complications:

  • Low: minor surgery (e.g., inguinal hernia & extremity surgery)

  • Intermediate: intra-abdominal operations (e.g., cholecystectomy)

  • High: intracranial & intrathoracic procedures, hip surgery

• Hematology consult, optimize treatment:

  • Hydroxyurea to ↑ fetal hemoglobin production

• Cancel non-emergent cases if patient experiencing a crisis

• Only low risk patients should be considered for outpatient surgery

• IV fluid to avoid dehydration while NPO

• Preoperative transfusion therapy:

  • Controversial without good evidence

  • Purpose is to correct pre-existing anemia, ↓ hemoglobin S concentration & ↑ adult hemoglobin

  • Consider target hemoglobin 100 or hematocrit 30% for intermediate & high risk surgeries & always have blood available for any surgery

  • Exchange transfusions are not routinely recommended

 

 

Acute chest syndrome (ACS)

 

• Background:

  • Second most common reason for hospitalization after vaso-occlusive crisis

  • Mortality 2-12%; accounts for 25% of deaths in sickle cell patients

  • Characterized by acute respiratory symptoms concurrent with new infiltrate on CXR

  • Spectrum of pathology:

    • Infection

    • Infarction (especially ribs)

    • Pulmonary sequestration

    • Fat embolism

  • Pulmonary vaso-occlusion due to sequestration of sickled cells in small pulmonary vessels

  • Infection or fat emboli may lead to vaso-occlusion & sequestration

  • Clinical picture: fever, tachypnea, pleuritic pain & cough 

  • CXR: normal to complete opacification but usually demonstrates a new lobar infiltrate:

    • Children: upper lobe disease common

    • Adults: multilobe & lower lobe disease more common

  • Strong relationship between ACS & stroke

• Treatment:

  • ​​Admit to monitored setting, may need ICU

    • Hydration to euvolemia

    • Oxygen, noninvasive PPV if necessary 

    • Bronchodilators (even if not wheezing) 

    • Broad spectrum antibiotics: infection is one of the most common causes of ACS 

    • Transfusion: both simple & exchange transfusion:

      • Simple transfusion: goal is to ↑ hematocrit to > 30%:

        • Indications:

          • To improve oxygenation, particularly in patients with oxygen saturation below 92% on room air & to prevent progression to respiratory failure

          • For accentuated anemia, defined as a hematocrit that is 10% to 20% below the patient's usual hematocrit, or with a dropping hematocrit during hospitalization

          • Clinical or radiological progression of disease but not impending respiratory failure

          • For patients in whom exchange transfusion will be delayed; simple transfusions may be used to temporize the clinical situation until the exchange transfusion can be performed

      • Exchange transfusion: goal is to ↓  the level of hemoglobin S to < 30%:  

        • Indications:

          • Progression of ACS despite simple transfusion

          • Severe hypoxemia

          • Multi-lobar disease

          • Previous history of severe ACS or cardiopulmonary disease

    • Analgesia: adequate analgesia of spine, thoracic, & abdominal pain is important to prevent hypoventilation & atelectasis

    • Possibly inhaled nitric oxide for severe cases

 

 

Acute pain crisis (Vaso-occlusive crisis)

 

• Anesthesia may be requested to assist with analgesia (e.g., patient-controlled analgesia)

• Typically occurs in long bones, ribs, spine, or abdomen

• Precipitants: infection, dehydration, hypothermia, hypoxia, stress, alcohol intake, menstruation

• Bone pain from ischemia & infarction of marrow or cortex

• Abdominal pain from bowel ischemia, organ infarction, or referred from the ribs

• Severity of pain can range from annoying to disabling 

• Treatment: rest, warmth, reassurance, analgesia, fluid replacement:

  • Oral analgesics may be sufficient for minor attacks

  • Opioids (IM, SC, IV, PO):

    • PCA opioids with baseline analgesia provided by background infusion or fentanyl patch

  • Acetaminophen & NSAIDs:

    • NSAIDS particularly good for bone pain

  • Ketamine as adjunct

  • Regional blocks as appropriate, epidural use has been reported

 

 

Pregnancy Considerations  

 

• Interaction with pregnancy:

  • Pregnancy typically exacerbates the complications of sickle cell anemia

  • Maternal mortality is as high as 1%

  • Pulmonary embolism & infection are the leading causes of death

• Management:

  • Hemoglobin goals:

    • > 80 for vaginal delivery 

    • > 100 for cesarean delivery

  • Epidural strongly recommended in labor to reduce stress/pain 

  • Safe to use either GA or neuraxial for cesarean section

  • Goals: avoid hypovolemia, hypoxemia, hypercarbia, hypothermia, pain, stress