Acute chest syndrome is a common pulmonary complication in sickle cell disease characterized by fever, respiratory symptoms, and new lung infiltrates. It is diagnosed clinically and confirmed with chest x-ray. Management involves oxygen supplementation, antibiotics, hydration, pain control, and blood transfusion if needed. Preventive measures include vaccination, penicillin prophylaxis, hydroxyurea for recurrent cases, and incentive spirometry during pain crises to reduce risk of acute chest syndrome episodes.

1. PRESENTED BY:-
Dr RAKESH SWAIN

2. DEFINITION
 Acute Chest Syndrome(ACS) is defined as an acute
illness characterised by fever and/or respiratory
symptoms, accompanied by a new pulmonary
infiltrate on chest X-ray.
 It is the most common form of acute pulmonary
disease in patients with SCD, occurring in almost one-
half of patients.

4. Pathophysiology of ACS

5. CLINICAL FEATURES
 Cardinal features:
 Hypoxia
 Tachypnoea
 Shortness of breath
 Tachycardia
 Chest signs include crepitations, bronchial breath
sounds, reduced air entry and dullness to percussion.
 Rhonchi may be heard
 In early stages chest examination may be normal.

6. SYMPTOMS CHILDREN ADULTS
Fever +++ ++
Cough ++ ++
Chest pain + ++
Dyspnoea + ++
Tachypnoea + +
Wheezing + +/-
Nasal flaring + +/-
Skeletal pain + ++
Hypoxia ++ +++
Haemoptysis +/- +
+++ frequent(>80%)
++ common(50-79%)
+ less common(10-49%)
+/- infrequent(<10%)

7. Differential diagnosis of hypoxia in
sickle cell disease
 Chest infection
 Pulmonary embolism
 Over- narcosis(opiate toxicity)
 Underventilation due to pain
 Fluid overload

8. INVESTIGATIONS
 Diagnosis can be difficult due to:
 Clinical features may be few
 Hypoxia is difficult to determine on clinical examination
unless severe
 Radiological signs often lag behind the physical signs
 Standard monitoring includes:
 Atleast 4hrly SpO2, HR, RR, BP
 Daily clinical examination
 Hb electrophoresis, CBC, Retic count, CXR, LFT, Blood
C/S, ABG, Sputum C/S and PCR, CT Scan

9. Chest Xray showing rapid progression of acute chest syndrome

11. MANAGEMENT
 The goals of therapy are:
 To correct underlying factors that contribute to
deoxygenation of hemoglobin including dehydration
and infections.
 To control pain
 To support the patient’s respiratory and haemodynamic
status.

12.  Oxygen therapy:
 Aim is to keep oxygen saturation >96%
 Chest physiotherapy:
 Incentive spirometry has been shown to be benficial in
children.
 Antimicrobials:
 Broad spectrum antibiotics including cover for atypical
organisms e.g. iv augmentin/cefuroxime/ceftriaxone and
oral clarithromycin/doxycycline.
 Specific guidance is required for pandemic flu

13.  Hydration:
 Oral or intravenous fluids with care taken to avoid
overload
 A fluid balance chart to be maintained
 If patient is hypovolemic, normal saline is appropriate to
maintain hemodynamic stability.
 If patient is euvolemic and receiving maintenance IV
fluids, 0.45% normal saline with or without glucose
should be used.
 If the patient is euvolemic and able to take oral fluids
adequately, this should be encouraged.

14.  Pain control:
 Adequate analgesia in patients with rib, thoracic or
abdominal pain is recommended to prevent splinting of
the diaphragm and the consequent cycle vicious cycle of
hypoventilation, atelectasis, hypoxia and sickling that
can occur.
 NSAIDs are useful. Due consideration should be given to
the optimal safe use of opiates.

15.  Thromboprophylaxis:
 Low molecular weight heparin(e.g. enoxaparin,
dalteparin, tinzaparin) at prophylactic doses is
recommended in the absence of any contraindications.
 Low dose unfractionated heparin (e.g. 5000 units sc
thrice daily)
 Fondaparinux 2.5mg SC daily
 Nebulised bronchodilators:
 Beneficial particularly in the presence of reactive airway
signs or if there is history of asthma.

16.  Transfusion:
 The degree of hypoxia and respiratory compromise
partly governs the need for and mode of blood
transfusion.
 Blood should be sickle negative, preferably less than
7days old and also matched for Rh D, C, E, c, e as well as
Kell antigens
 Prophylactic red blood cell transfusions, typically with a
goal of reducing the maximum HgbS level to below 30%
in individuals with homozygous sickle mutation (HbSS),
have been shown to reduce the incidence of
vasoocclusive pain and acute chest syndrome events.

17. PREVENTION
 Secondary prevention:
 Hydroxyurea decrease the incidence of ACS in patients
with recurrent severe pain and should be considered in
any patient who has one or more episode of acute chest
syndrome.

18.  During crisis:
 Patients who present in sickle crisis with chest, sternal,
rib or back pain and post abdominal surgery should
commence incentive spirometry or chest physiotherapy.
 Blood transfusion:
 This should be considered prior to surgery in patients
deemed to be particularly at risk taking into account
past history of ACS, severity of phenotype and or type of
surgery planned.

19.  Other useful measures:
 Optimize vaccination status
 Penicillin prophylaxis (erythromycin if allergic to
penicillin)
 Smoking cessation
 Consider echocardiogram and PFT – atleast 4 weeks
following acute episode.

20. TYPES OF SICKLE CELL CRISIS
 Painful crisis:
 The most common type of sickle crisis presenting with
acute bone pain due to bone infarction.
 Mild painful episodes may be managed at home but
severe painful episodes often require hospital admission
for opiate analgesic.
 Acute chest syndrome:
 It is a mixture of pain, pulmonary infarction and is often
precipitated by respiratory infection.

21.  Haemolytic crisis:
 All patient with sickle cell disease have a chronic
ongoing haemolytic anaemia.
 Visceral sequestration:
 Patients can present with massive hepatomegaly or
splenomegaly due to visceral sequestration of sickled
red cells which leads to severe anaemia.
 Aplastic crisis:
 Due to high turnover of red cells in patients with sickle
cell disease any interruption to red cell production may
have severe consequences and induce an aplastic crisis
e.g. parvovirus B19 infection