From the Guidelines
Acute chest syndrome in sickle cell disease requires prompt and aggressive treatment, including supplemental oxygen, intravenous fluids, analgesics, antibiotics, and possibly transfusion therapy, with red flag signs necessitating immediate intervention including respiratory rate >30 breaths/minute, oxygen saturation <92% despite supplemental oxygen, and progressive respiratory distress. The treatment approach should prioritize maintaining oxygen saturation above 92%, careful hydration at 1.5 times maintenance rate, and pain management with opioids [ 1 ]. Empiric antibiotics should cover typical and atypical pathogens, typically with a third-generation cephalosporin plus a macrolide. Incentive spirometry every 2 hours while awake prevents atelectasis.
Key Components of Treatment
- Supplemental oxygen to maintain saturation above 92%
- Intravenous fluids for hydration at 1.5 times maintenance rate
- Analgesics for pain management, typically opioids
- Empiric antibiotics covering typical and atypical pathogens
- Incentive spirometry to prevent atelectasis
Transfusion Therapy
Transfusion therapy may be necessary, with simple transfusion to increase hemoglobin to 10 g/dL or exchange transfusion for severe cases [ 1 ]. The choice between simple and exchange transfusion depends on the severity of the acute chest syndrome and the patient's hemoglobin level.
Red Flag Signs
Red flag signs requiring immediate intervention include:
- Respiratory rate >30 breaths/minute
- Oxygen saturation <92% despite supplemental oxygen
- Progressive respiratory distress
- Altered mental status
- Multi-lobar involvement on chest imaging
- Declining hemoglobin levels (especially >1 g/dL from baseline)
- Platelet count <200,000/μL
These signs may indicate progression to respiratory failure, emphasizing the need for close monitoring in an inpatient setting, preferably with hematology consultation, until clinical improvement occurs [ 1 ].
From the Research
Treatment of Acute Chest Syndrome
- The primary goal of treatment is to prevent and manage acute respiratory failure, and minimize irreversible lung damage 2
- Management focuses on analgesia, oxygen supplementation, incentive spirometry, bronchodilators, rehydration, antibiotics, consideration for transfusion, and specialist consultation 3
- Empiric antibiotics that cover atypical pathogens are necessary, along with measures to increase oxygen-carrying capacity in those with hypoxemia, such as simple transfusion or exchange transfusion 3
- Blood transfusion is often used as a therapeutic intervention to increase blood's oxygen-carrying capacity and reduce complications by reducing hemoglobin S (HbS) percentage 4
Management of Acute Chest Syndrome
- Early diagnosis and timely management of ACS results in better outcomes 5
- The management of ACS is based on limited evidence and is currently guided primarily by expert opinion 4
- Randomized controlled trials have evaluated the efficacy of various treatment modalities, including incentive spirometry, positive expiratory pressure device, intravenous dexamethasone, oral vs. intravenous morphine, inhaled nitric oxide, unfractionated heparin, and blood transfusion in the prevention or treatment of ACS 5
- Although there are guidelines for ACS treatment, the available evidence is very limited to delineating the effectiveness of various interventions in ACS management 5
Red Flag Signs of Acute Chest Syndrome
- Respiratory symptoms, including fever, cough, chest pain, and shortness of breath, which can progress to respiratory failure requiring mechanical ventilation in 20% of adult patients 3
- New radiodensity on chest imaging in a patient with SCD 3
- Hypoxia, bronchial hyperresponsiveness, and opioid use are prominent risk factors that precipitate ACS 2
- Infection is the most common identifiable cause for ACS, but other important triggers are vaso-occlusive crisis (VOC) and asthma 6