File - Department Of Pulmonary Medicine

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DR. KOMALDEEP
JUNIOR RESIDENT
PULMONARY MED
TBHP
HISTORY
 460 BC hippocratic physicians recommended
treating empyema with open drainage.
 Napolean’s surgeon dupuytren, whose name is
linked to the palmar fascia contractures of liver
disease, died of empyema in 1835 after
declaring he would “rather die at hands of God
than of surgeons”
 Sir William Osler who thought “empyema
needs a surgeon and 3in. Of cold steel , instead
of a fool of a physician” provided a compelling
description of his own empyema before
succumbing to disease.
THE WORD: EMPYEMA
 Em=within
 Pyema=accumulation of pus
 Empyema is known to be the formation and collection of pus
within a naturally present cavity inside the body primarily the
pleural cavity
 Light’s : “I prefer to reserve the term empyema for those pleural
effusions with thick, purulent appearing pleural fluid”.
Other descriptions
Weese et al. defined an empyema as pleural fluid with
 a sp. Gravity >1.018,
 a WBC count >500 cells/mm3 or
 a protein level >2.5g/dl.
Vianna defined an empyema as pleural fluid on which
 the bacterial cultures are positive or
 the WBC count is > 15,000/mm3 and
 the protein level is >3.0g/dl.
•abscess
Empyema is different
from an abscess
because the latter is
the formation And
collection of pus in a
newly formed cavity
inside the body.
 Parapneumonic
effusion:
 Any pleural effusion associated with bacterial
pneumonia , lung abscess or bronchiectasis is
a parapneumonic effusion.
 Many complicated parapneumonic effusions
are empyemas.
 Some patients with empyema have no
associated pneumonic process.
Introduction of infection
Non-traumatic
Traumatic
 Instrumentation and rupture of esophagus
 Direct extension from an
 Leakage of an esophageal anastomosis after
adjacent site : lung infection

 Aspiration pneumonia
 Post-obstructive pneumonia


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 Bronchiectasis, lung abscess

resection
Development of a bronchopleural fistula following
pneumonectomy
Pleual aspiration/ tube drainage
Abdominal sepsis: subphrenic abscess , liver
abscess
Sepsis in the pharynx, thoracic spine or chest wall
may extend into the pleura via tissue planes or
mediastinum
Non- surgical trauma:
Gun shot wounds, blast injuries and stab wounds.
Pathology
(1) Exudative STAGE
 Once infected by pathogenic organisms, the connective tissue layers
within the pleural memberanes become oedematous and produce
an exudation of sterile proteinaceous fluid that starts to fill the
pleural cavity.
 The deepest layers of the pleural membranes are relatively
impervious so that infection tends to be contained within the pleural
cavity itself and spread beyond it is unusual.
 At this stage, the pleural fluid is thin with a relatively low white cell
count and the visceral pleura and underlying lung remain mobile.
 Fluid at this stage is having a low WBC count, low LDH level and a
normal glucose level and ph.
(2) Fibrinopurulent STAGE
 If the infection proceeds unchecked by antimicrobial agents, the inflammatory
process continues so that newly formed layers of fibrin become laid down on
the epithelial surface within the pleural cavity, particularly on the pleural cavity.
 The empyma fluid now becomes more thicker and more turbid, containing, a
higher white cell count.
 Such empyemas may become loculated into smaller collections by the
development of fibrinous bands which prevent the extension of empyema but
making the work of percutaneous aspiration difficult or impossible.
 With the deposition of fibrin on both pleural surfaces, lung movements in this
stage may become increasingly restricted.
 The pleural fluid ph and glucose levels becomes progressively lower and LDH
level becomes progressively higher.
(3) ORGANIZATIONAL STAGE
 Depending upon the nature of the infecting organism and whether
or not antibiotics and drainage procedures have been employed,
these thickened fibrinous layers organize as collagen and become
vascularized by an ingrowth of capillaries.
 This stage may begin within two weeks but usually takes 4-6 weeks
to develop to a point at which the empyema cavity becomes
surrounded by a cortex, peel or rind that may be more than 2 cm
thick.
 This inelastic pleural peel encases the lung and renders it virtually
functionless.
 By this time the empyema contains frank pus, which may be viscid.
 Ultimately, an inadequately treated empyema cavity may
become obliterated and its rind may calcify, producing a socalled firothorax, particularly in case of old tuberculous pleural
infection.
 The inner layers of the thickened empyema cortex continue to
show a considerable inflammatory cell infiltrate and the fibrous
outermost layers exert an increasingly restrictive effect, both
compressing the underlying lung( the so called “trapped lung”
effect) and also tending to draw the overlying ribs together,
ultimately producing a chest deformity with a dorsal scoliosis
that is concave towards the affected side.
 Dry “sicca” pleuritis stage, the inflammatory process of the
pulmonary parenchyma extends to the visceral pleura, causing a
local pleuritic reaction.
 This leads to a pleural rub and a characteristic pleuritic chest
pain which originates from the sensitive innervations of the
adjacent parietal pleura.
Clinical stages
• Acute stage :
within the first 2 weeks of the onset.
• Chronic Stage :
after 2 weeks or with the formation of the thick peel and
loculations.
Causes for chronicity
 Inadequate Tube Drainage.
 Chronic pulmonary Disease( T.B. or Fungal Infection)
 Immunosupressed patients.
 Presence of Foreign body within the pleural space.
bacteriologic features
Influence of pre-disposing factors:
 CAP: pneumococcal
 HAP: MRSA
 Aspiration or lung abscess: anaerobes
 Infection from below the diaphragm: gram negative enteric bacilli
 External trauma/haemothorax: staph. Aureus
 Tuberculous empyema – same mechanism as TB pl. effusion with
spillage of large amount of mycobacterium into pleural space 
purulent effusion that requires surgical intervention and can result in
pleural fibrosis and restrictive lung disease
BACTERIOLOGIC FEATURES
CONT..
Influence of age:
 Anaerobes in elderly
 S. pneumoniae in young ambulatory patients
 Children: h. influenzae
Uncommon microbial causes: fungal(cryptococcus neoformans,
blastomyces,coccidioides,histoplasmosis) , actinomyces,
nocardia, clostridia, echinococcus spp. , protozoa( trichomonas,
entamoeba)
Clinical presentation
Aerobic bacterial infections: acute febrile illness
Anaerobic bacterial infections:
 Subacute illness.
 Median symptom duration 10 days
 Predisposing factors present : h/o alcoholism, an
episode of unconsciousness , poor oral hygeine
Symptoms
Signs
Generalized malaise
Oral cavity: decaying teeth
Fever
Finger clubbing: in chronic empyema
Pleural pain
Chest examn: similar to that of pleural
effusion
Warm, tender and bulging ICS
Cough:
If BPF patent, variable quantities of
purulent sputum, can be foul smelling and
associated with postural variation.
Empyema necessitans: the suppuration
process if undrained and uncontrolled by
AB, may extend beyond the pleural cavity,
with pointing occurring in an ICS close to
the sternum where chest wall is thinnest.
Dyspnoea: a. compression of underlying
lung by empyema
b. Primary disease involving lung itself
Discharging sinus: EN will then rupture
through the chest wall to s/o tissues,
ultimately reaching the skin surface
leading to discharging sinus.
diagnosis
 History
 Clinical features
 Chest radiograph
 Ultrasound chest
 CT chest
 Thoracentesis : empyema fluid : appearance, mirobiology, biochemistry
Chest x-ray
 Decubitus view: suspect side down – fluid b/w chest wall and inferior part of lung
Suspect side up : parenchymal infiltrate.
 In early stages: identical to those of uncomplicated pl. eff.
 As the time passes by, fibrosis develops around the empyema cavity so that fluid is
contained in one location irrespective of patient’s position.
 “D shaped shadow” may be visible along with obliteration of CP angle.
 Parenchymal lesion may be visible : consolidation, lung abscess
 Air fluid level: pneumothorax : spontaneous or iatrogenic
broncho-pleural fistula
presence of gas forming organisms such as clostridia
ultrasound
 May show septa when there is loculation
 Also helpful in targeting an empyema for needle or tube drainage.
 Portable
 Helpful in distinguishing b/w
Loculated pyopneumothorax
And
Peripheral lung abscess
Computed tomography
 Able to detect underlying abnormalities such as oesophageal perforation ,
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bronchial carcinoma and associated lymphadenopathy .
It also aids in the differentiation between empyema and lung abscess.
Empyemas are usually lenticular in shape, compress the lung, and create
obtuse angles as they follow the contour of the chest wall.
There is usually an indistinct border between lung parenchyma and a lung
abscess, which forms an acute angle where contact with the chest wall is
made.
The ‘split pleura’ sign, where both parietal and visceral pleura enhances
showing their separation, can be present in an empyema.
 Computed tomography (CT) is not as accurate as ultrasound in
detecting septations and requires transferring the patient.
Empyema fluid :
 GROSS EXAMN : COLOUR, TURBIDITY AND ODOR
 Can be distinguished from pleural fluid that is turbid due to chyle i.e.
chylothorax by use of centrifugation in which case a whitish layer of
chylomicrons is found on surface of pleural fluid.
 appearance: E. histolytica: anchovy sauce
actinomyces: sulfur granules
 Smell: putrid (FECULENT) smell in anaerobic infection.
 Microbiology :
ZN
Gram’s
culture: aerobic as well as anaerobic, mycobacterial and
fungal
 PCR
 Cytology : total and differential WBC counts
 Ph : should not be done as it will plug up the blood gas
machines.
Biochemistry of empyema
fluid
 Low p H
 Low glucose
 Raised LDH
 Decreased pH and glucose occur as a result of leucocyte and bacterial
anaerobic metabolism of glucose and process that produce lactic acid.
 Exception The one situation in which pleural fluid ph is not reduced is
when the offending organism is of the proteus sp.. These organisms produce
ammonia by their urea splitting ability which leads to and elevated pleural
fluid ph.
Non significant PE
N
NAUGHTY
Typical
parapneumonic PE
T
TINY
Borderline
complicated PE
B
BUTTERFLIES
Simple complicated
PE
S
SUCK
Complex complicated
PE
C
COMPLETE
Simple empyema
S
SQUASH
Complex empyema
C
CONTAINER
complications
 Rupture into the lung: Dissection into
lung parenchyma
BronchoPleural fistula and
pyopneumothorax
 Spread to the subcutaneous
tissue: Dissection through chest wall
Empyema Necessitans
 Dissection into abdominal
cavity.
 Septicaemia & septic shock.
Management
Principles of management:
 Control of the Infection process.
 Drainage of pus form the pleura.
 Obliteration of the space & complete Re-expansion of
the Lung.
MANAGEMENT OPTIONS:
 General
 Medical
 Surgery
general
 Supportive



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Bed rest
Analgesia
Oxygen
Fluids
 Identify the cause



Malnutrition
TB
HIV
antibiotic selection
 If the fluid’s gram stain and culture reports are available, it should guide the choice of
AB.
 The initial antibiotic selection : some do not penetrate pleura.
 Metronidazole> penicillin>clindamycin>vancomycin>ceftriaxone>gentamicin
 Quinolones and clarithromycin also penetrate well
1.Severe CAP : fluoroquinolones(levofloxacin, moxifloxacin, gatifloxacin or
gemifloxacin)
Advanced macrolide(azithromycin or clindamycin) plus b-lactam(cefotaxime,
ceftriaxone)
2. If pseudomonas suspected: piperacilin-tazobactam, imipenem, meropenem
3. Anaerobic: clindamycin or metronidazole.
4. MRSA: vancomycin until culture results are available.
Surgical management
“those diseases that medicines do not cure are cured
by the knife”
TECHNIQUE DEPENDS UPON THE STAGE OF EMPYEMA
CLOSED: INTERMITTENT (REPEATED ASPIRATION OR
THORACOCENTESIS)
CONTINUOUS (INERCOASTAL DRAINAGE )
OPEN: RIB RESECTION
ELOESSER FLAP
CLOSED
 These methods are more likely to appertain in the exudative
stage but may be continued into the fibrino-purulent stage in some
cases.
 THORACOCENTESIS : frequency with which thoracentesis is
repeated depends upon the rate at which pus reaccumulates,
which in turn is judged by clinical and radiographic appearance.
 Such treatment along with antibiotics is appropriate for many
individuals with pleural empyema and these patients may have a
shorter and less complicated stay than those by tube drainage.
Closed tube drainage
 Tube is placed under local anaesthesia into most dependent part of empyema


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


determined by USG/CT guidance and is connected to an underwater-seal drainage
system.
The relatively large (28 to 36F ) tubes have been recommended because of the belief
that smaller tubes would become obstructed with the thick fluid.
The advantage of the smaller tube is that it is easier to insert and is less painful to the
patient.
Patency is maintained with irrigation and fibrinolytic therapy
If the patient has not demonstrated significant improvement within 24hrs of initiating
tube thoracostomy, either the pleural drainage is unsatisfactory(tube placed in wrong
position, loculations) or the patient is receiving the wrong antibiotic.
Advantages: successful when infected material is too viscid to remove by manual
aspiration.
Disadvantages: greater discomfort and immobility for the patient
introduction of new infection at drainage site
tube blocked by fibrin clot
Indications for removal of
tube:
 Volume of the pleural drainage is less than 50ml for 24 hrs and
until the draining fluid becomes clear yellow.
 The amount of sediment (representing WBCs and debris) in
the collection system should not be more than 5ml.
 Tube ceases to work
Because it serves no useful purpose rather it as a conduit for
pleural super-infection.
Closed drainage
Successful:
 Empyema is small
 Is started In acute exudative or early fibrinopurulent stagees of infection
In this case, the wall of the empyema cavity gradually becomes absorbed
allowing re-expansion of the underlying lung and obliteration of space.
It may fail:
 If the pus is too thick to drain by thoracentesis or tube
 BPF has developed
 Pockets of pus become loculated and inaccessible.
If drainage is inadequate, ultrasonography or CT should be performed to
delineate which factor is responsible.
Then, more invasive surgical procedures are required.
Intrapleural
streptokinase
 The pleural fluid loculations are produced by fibrin membranes that prevent
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the spread of the infected pleural fluid throughout the body, but which make
drainage of the pleural space difficult.
Intrapleural fibrinolytics will destroy the fibrin membranes and facilitate
drainage of the pleural fluid.
Indications
Acute or fibrino purulent stage
Presence of loculations.
Incomplete drainage after tube insertion
Contraindications:
Chronic stage
Post-operative empyema
Empyema with BPF.
fibrinolytics
 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)
vats
 Advantages:
 the loculi can be disrupted
 pleural space can be completely drained
 Chest tube can be optimally placed.
 In addition, if lung is trapped(not expanded), the VATS
incision can be enlarged so that decortication can be
completed with a full thoracotomy.
Pulmonary decortication
 In a non-medical aspect, decortication is the removal of the bark, husk, or
outer layer, or peel of an object.
 It is a surgical procedure that involves the removal of a dysfunctional layer
covering the lungs and evacuation of all pus and debris from the pleural
space.
 The primary aim of performing lung decortication is to be able to promote
lung expansion and chest wall compliance.
 IF AFTER 6MONTHS, PLEURA REMAINS THICKENED AND THE
PATIENT’S PFTS IS SIGNIFICANTLY REDUCED TO LIMIT
ACTIVITIES, DECORTICATION SHOULD BE CONSIDERED
Open drainage
Rib resection: resecting segments of one to three ribs overlying the lower part
of empyma cavity and inserting large bore tubes into the empyema cavity.
Following this, tubes are irrigated daily with a mild antiseptic solution and daily
redressed.
Successful open drainage results in gradual obliteration of empyema space.
Open window thoracostomy (eloesser flap) :
involves the removal of sections of two or more ribs in order to fashion a larger
stoma, which is kept open by suturing the skin to the parietal pleura/cortex
thereby creating a pleurocutaneous flap, stoma closed if the underlying lung reexpands or may occasionally be left permanently open with daily dressings.
Empyema associated with bpf
Adequate pleural drainage is crucial: an emergency
 Pleural fluid if not drained exteriorly with chest tubes is likely to drained
interiorly into the lung
 The bacteria then spread throughout the broncho-pulmonary tree and an
overwhelming pneumonia can result.
 Drainage should be instituted immediately to prevent the possibility of
contaminating the entire respiratory system by the infected pleural fluid.
How to suspect: a patient with pleural fluid collection:
 Raises more sputum than would be expected
 With postural variation
 On x-ray(upright position): presence of an air fluid level in the pleural space
 Need USG and CT chest to differentiate from a peripheral lung abscess.
Empyema distal to an obstructed
bronchus
• Contraindication for chest tube
placement
• If chest tubes placed: bronchial obstruction will
prevent the expansion of underlying lung.
• What should be done: appropriate AB should be
administered along with therapy for obstructed
bronchus: radiotherapy, endo-bronchial stent or laser
therapy. Once obstruction relieved, ICT to be done.
Post traumatic empyema
Factors leading to development of empyema:
 Retained hemothorax
 Pulmonary contusion
 Multiple chest tube placement
Management : similar to that of other para-pneumonic
effusions.
Post pneumonectomy empyema
how to suspect : 2nd day to 7yrs (4wks)
 A febrile illness with signs of systemic toxicity
 Expectoration of large amounts of pleural fluid
 An air-fluid level in the pneumonectomy space
 Drainage of purulent material from surgical incision
 Mediastinal shift towards contralateral side
Organism responsible: staph aureus
Diagnosis and treatment : all aptients: AB + chest tube placement
Scheme to move forward
 Antibiotics
 Pleural aspiration
 Chest tube drainage
 Chest tube drainage with I/P fibrinolytics
 Thoracoscopy
 Decortication
prognosis
 Favourable in patients started on appropriate antibiotic
 Early chest tube drainage is beneficial.
 Decortication or open drainage has decreased
mortality and morbidity
 Mortality 6-12%
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