The management of empyema the practical vs. ideal approach R. Masekela University of Pretoria

Case presentation

Patient A.K

11 month old baby boy Main Complaint : Coughing - two weeks non productive Fever - two weeks Vomiting - after coughing Diarrhoea - one week, brown and loose no blood noted in stool 3 weeks before admission to primary care hospital was seen with a cough and fever and treated with Amoxycillin and Paracetamol. Did not improve after a week and was taken back.

• Diagnosis with bronchopneumonia and a pleural effusion Ampicillin and Amikacin for 6 days Vancomycin for 2 days • PMH : No previous admissions, healthy • Family history : no atopy, no asthma •No TB contacts

On Examination Mass 10kg, 100% expected Length 78cm, 100% expected Vitals : RR 60, Pulse 110, Temp 37.5, BP 90/40 Sats 90% 5% dehydrated Chest: Grunting, Nasal flaring, subcostal recessions, bilateral scattered crepitations, decreased air entry right lower lobe and stony dullness right base

30/5/07

ICD inserted

Hb MCV Platelets WCC Neutrophils Lymphocytes Monocytes Na K CL CO2 Urea Creatinine Anion Gap CRP ESR NGA - AFB 145 4.7

108 14 9.1

83 28 19/5 11.9

69.9

961 27.88

22/5 11.0

71.9

729 16.70

30/5 9.8

.30

844 16.77

10.23

4.53

2.01

140 3.2

105 20 1.5

23 18 140 4.8

105 16 <1.0

30 24 221.5

72.8

69 -ve 144.4

-ve Pleural pus specimen - 31/05/07 Cultured Staph. Aureus R - Penicillin/ampicillin R - Erythromycin R - Clindamycin S - Cloxacillin

1/06/07

HISTORY

 460 BC     Em=within Pyema=accumulation of pus Hippocratic physicians recommended treating empyema with open drainage “those diseases that medicines do not cure are cured by the knife”

HISTORY cont’d

 1876- Hewitt described a method of closed drainage of the chest in which a rubber tube was placed into the empyema cavity and drained via the water seal drainage  Early 20th century introduction of surgical therapies for empyema  thoracoplasty, decortication.

Empyema

 Empyema: presence of pus in the pleural space  Boys affected more than girls  First world 0.6-3% bacterial pneumonias

Megan et al Curr Opinion Pediatr 2007

 HIV positive 8% of South African children

Zar et al. Acta Paediatrica 2001

Normal pleural fluid

 Pleural space potential space 10-24µm  0.1-0.2 ml/kg pleural fluid  Starlings forces: filtration and reabsorption  pH 7.6

Light’s criteria

 Pleural fluid protein: serum protein > O.5

 Pleural fluid : serum LDH >0.6

 Pleural fluid LDH > 2/3 upper limit of serum LDH Light R. Chest 1995;108:299-301

Other minor criteria

 Cholesterol > 45mg/dl  Protein content > 3.0 g/dl  pH <7.2

 Glucose < 50% serum

Parapneumonic pleural effusions

 3 groups or stages based on pathogenesis:  Uncomplicated parapneumonic effusion  Complicated parapneumonic effusion  Thoracic empyema.

Exudative stage

 Sterile pleural fluid accumulates in pleural space.  Pleural fluid originates in lung interstitial spaces and in capillaries of visceral pleura due to increased permeability.

 Pleural fluid ↓ WBC ↓ levels are normal LDH level, glucose and pH  Effusions resolve with antibiotic therapy.

Fibropurulent stage

 Bacterial invasion of the pleural space occurs debris → accumulation of neutrophils, bacteria and cellular  Deposition of fibrin  loculations  Pleural fluid pH <7.2 , glucose levels ↓ , LDH level >1000IU/l

Organizational stage

 Fibroblasts grow into the exudates from both the visceral and parietal pleural surfaces  They produce an inelastic membrane called pleural peel.  Thick pleural fluid

Complications

 Dissect into lung parenchyma → bronchopleural fistulas and pyopneumothorax  Dissection through chest wall (empyema necessitatis) RARE  Dissection into abdominal cavity

Organisms

 Strep. pneumonia   HIV infection 41X risk of invasive disease and more resistance

Mahdi et al PIDJ 2000

Incidence increasing in developing world  S. aureus   Increasing incidence CA-MRSA in HIV-infected children 50% in Natal blood culture positive. McNally et al. Lancet 2007 67 of 100 empyema. Goel et al. J Tropical Peadiatr 1999  H. influenza type b  Gram negatives    Pseudomonas Klebsiella E.coli

Organisms

 Tuberculosis  Rare cause but common PPE  Fungi  Viral  Atypical organism  Mycoplasma

Clinical manifestations

 Aerobic bacterial pneumonia  An acute febrile illness with chest pain, sputum production, and leukocytosis.

 A complicated parapneumonic effusion with presence of a fever lasting more than 48 hours after initiation of antibiotic therapy.

Clinical manifestation

 Anaerobic bacterial infection      Usually presents with subacute illness.

symptoms persisting for more than 7 days.

 60% of patients have weight loss.

Poor oral hygiene Factors predisposing to recurrent aspiration.

Chest x-rays

 PA and lateral decubitus  Adult studies sensitivity 67% and specificity 70%

Heffner JE. Clinics Chest Med 1999;20:607-622

 PA at least 400ml fluid vs. 50ml lateral decubitus  Assess for loculations

Ultrasound

 Classification    Stage 1: anechoic fluid Stage 2: loculations Stage 3: solid peel  Guide placement of intercostal drain Hogan MJ, Cooley BD. Paediatric Resp Reviews 2008;9:77-84

Ultrasound

 Size of effusion  Differentiate consolidation from empyema  Unreliable predictor of disease severity

CT scan

 Anatomical  Parenchymal lesions    Endobronchial lesions Mediastinal lesions Lung abscess

Management

 IV antibiotics and intercostal drainage  Fibrinolytics  Video -Assisted Thoracoscopic Surgery (VATS)  Open thoracotomy and decortication

Management

  Supportive     Bed rest Analgesia Oxygen Fluids Identify the cause    Malnutrition TB HIV

Antibiotic therapy

Zampoli M, Zar H. SAJCH 2007;1(3):121-8

Fibrinolytics

 Degrade fibrin, blood clots and pleural loculi in pleural space  Streptokinase: 15 000U/kg in 20-50ml saline once daily for 3 days (vial 750 000U R1400, 1 million units R2700)  Urokinase: 40 000u in 40ml saline (> 1 year) or 10 000 in 10 ml BD for 3 days(< 1 year)  tPA 0.1mg/kg in 10-30ml saline dwell time 1 hour (50mg vial R3100)

Fibrinolytic therapy versus conservative managements: Cochrane review

 Seven studies 761 participants  No significant difference in risk of death (RR 1.08;95% CI 0.69-1.68)  Reduction in risk of treatment failure (RR 0.63;95% CI 0.46-0.85)  Fibrinolytics confer significant benefit and reduce requirement for surgical intervention (in early studies published) Cameron R, Davies HR. Cochrane review April 23 2008 Issue 2

VATS

 Can be done as primary procedure  Experienced surgeon necessary  Benefits     lower mortality Re-intervention Reduced length of hospital stay Reduced hospital costs

Aziz et al Surgical infections 2008;9(3):317-23

Thoracotomy

 Treatment of choice if no experience or success with VATS  Early and accurate diagnosis and therapy  Attempt “mini” vs. full procedure  Mortality reduced

Ideal approach

Fuller MK, Helmrath MA. Curr Opinion Pediatrics 2007;19:328-332

Practical

 Early diagnosis    CXR include lateral decubitus Early antibiotics Early chest drainage  Loculations   Early referral Thoracotomy if no improvement with ICD placement and correct antibiotics

Prognosis

 Favourable in patients started on appropriate antibiotic  Early chest tube drainage is beneficial.  Decortication or open drainage has decreased mortality and morbidity.

Prognosis

 Mortality 6-12%  Complications    Bronchopleural fistula Tension pneumatocoele Fibrothorax

4/06/07

Acknowledgements

     Prof R Green Dr O Kitchin Dr S Risenga Dr Moodley ICU staff