aspiration pneumonia in livestock :predisposing factors& remedy (with special reference to...

DISSERTATION ON

ASPIRATION PNEUMONIA:PREDESPOSING FACTORS

& REMEDY

Submitted to – Dr. Ankur sharmaSubmitted by – Prince chauhan

(with special reference to kerosene Aspiration pneumonia)

ASPIRATION PNEUMONIA

INTRODUCTIONAspiration is defined as the inhalation of foreign

material into the airways beyond the vocal cords. The content of the aspirate is variable and may

comprise secretions, blood, bacteria, liquids and food particles.

Most aspirates in the clinical scenarios are liquid in nature. It is the composition of the aspirate that determines the extent and progression of the injury on the pulmonary parenchyma.

Predisposing Factors

Altered level of consciousness • stroke • seizures • intoxication (alcohol and other drugs) • head trauma • anaesthesia


Mechanical disruption of usual defences

• nasogastric tube• Cleft palate• Endotracheal intubation• Tracheostomy• upper gastrointestinal endoscopy• bronchoscopy • Holding tongue while drenching• Recumbent position

Neuromuscular disease

• multiple sclerosis • Parkinson’s disease • myasthenia gravis • bulbar or pseudo bulbar

palsy



Gastro-oesophageal disorders • incompetent cardiac sphincter • oesophageal stricture • neoplasm • gastric outlet obstruction • protracted vomiting

CLASSIFICATIONAspiration pneumonia is broadly classified into two

categories

BACTERIAL PNEUMONIA

CHEMICAL PNEUMONITIS

BACTERIAL PNEUMONIAAspiration of oropharyngeal contents, for example

due to swallowing difficulty, will cause bacterial pneumonia with mouth organisms predominating.

The micro-organisms that commonly cause these pneumonias, are Streptococcus pneumoniae, Haemophilus influenza, Staphylococcus aureus, and gram-negative bacteria.

They generally are relatively virulent so that only a small inoculum is required to result in a pneumonia.

INTRODUCTION

Multiple substances are directly toxic to the lungs or stimulate an inflammatory response when aspirated;

gastric acid is the most common such aspirated substance

Aspirated gasoline and kerosene & petroleum products (particularly of low viscosity, such as petroleum jelly) can also cause a chemical pneumonitis.


CHEMICAL PNEUMONITIS• Most aspirates in the clinical scenarios are liquid in

nature.• It is the composition of the aspirate that determines

the extent and progression of the injury on the pulmonary parenchyma.

• Aspiration of gastric contents will cause a chemical pneumonitis (e.g. Mendelson’s syndrome) because the gastric contents are usually sterile, but their acidity results in the rapid development of inflammation in the lungs.


•The equivalent inhaled volume in a 50-kg calf would be about 15 mL.

• a volume greater than 0.3 mL/kg (B.W.) and with a pH < 2.5 are required to cause aspiration pneumonitis (Marik 2001).

CHEMICAL PNEUMONITISPathophysiologyThe first phase peaks at 1 to2 hours after

aspiration and presumably results from thedirect caustic effect of the low pH on the alveolar-capillary wall lining cells. The second phase, which peaks at 4 to 6 hours

is associated with infiltration of neutrophils into the alveoli and lung interstitium with a histologic picture of acute inflammation

PATHOPHYSIOLOGY OF PNEUMONIA CAUSED KEROSENE ASPIRATIONPhysicochemical Properties of kerosene

Kerosene is a thin, clear liquid formed from a complex mixture of hydrocarbons, with density of 0.78–0.81 g/cm3. It is obtained from the fractional distillation of petroleum between 150 and 275°C, resulting in a mixture of carbon chains that typically contain between 12 and 15 carbon atoms per molecule

• Low viscosity(60ssu)- deep penetration into tracheobronchial tree

• High volatility- displaces the alveolar gases & interfere with ventilation & CNS depression

• Low surface tension- enhance spreading on lung tissue• <1ml- significant injury

Physicochemical Properties of kerosene

PATHOPHYSIOLOGY OF PNEUMONIA CAUSED KEROSENE ASPIRATION


• Pulmonary pathology -inflammatory cell infiltrates and morphological changes to tracheal epithelia

• Kerosene can cause significant pulmonary disease by inducing an inflammatory response, haemorrhagic exudative alveolitis, and loss of surfactant function.

• decrease in surfactant results in alveolar collapse,• Secondary effects in the lungs include pneumothorax,

pneumatocele, or bronchopleural fistula.


• cardiovascular changes -resembling atherosclerosis• decrease in surfactant results in alveolar collapse,• ventilation – perfusion mismatch and hypoxemia.• Hemorrhagic alveolitis can occur which peaks 3

days after ingestion.• The end result of kerosene aspiration is interstitial

inflammation, intra-alveolar haemorrhage and edema, hyperaemia, bronchial necrosis, and vascular necrosis

Symptoms & clinical manifestations

•Abrupt onset of dyspnea• fever•Diffuse crackles on exam•Tachypnea•Transient cyanosis•Cough productive of putrid,

foul-tasting/pink frothy sputum•diffuse crackles•wheezing

Symptoms & clinical manifestations

Immediate Signs or Symptoms of Acute Exposure of kerosene aspiration•Headache•Drowsiness• Incoordination•pneumonitis with choking, & cough• cyanosis and fever.

Treatment•Mainstay of treatment is SUPPORTIVE•Avoidance of gastric emptying as it can increases risk of

aspiration•Ventilator support may be necessary•Corticosteroids: beneficial in animals•Antibiotics can be used but supportive & medical care is

essential•Up to 25% of patients have bacterial superinfection

(Dines et al)

TreatmentINDICATIONS FOR ANTIBIOTICS•Recurrence of fever after first 48 hours• Leukocytosis after first 48 hours• Increase infiltrate in chest radiograph• Sputum or tracheal aspiration positive for bacteria

Infectious Diseases Society of America (IDSA) guidelines recommend a -β lactam/ -β lactamase inhibitor, clindamycin or amoxicillin

Management of aspiration pneumonia

Supplement oxygen & close monitoringSelective beta 2 agonist for bronchospasmEpinephrine avoided- can cause fatal arrhythmias in kerosene

sensitised myocardiumDo not induce vomiting (emesis).

Therapy in cases of uncomplicated chemical pneumonitis involves• airway clearance• correcting the hypoxia by using oxygen supplementation


FLUID THERAPY• Intravenous fluid therapy is indicated as fluid loss is

increased due to panting,tachypnoea & increase in mucus production•providing hydration is necessary to liquefy pulmonary

secretions, enabling more rapid clearance of mucus from the airways•Avoid giving excess of fluid too, as it can lead to pulmonary edema.

PREVENTIONStrategies to prevent aspiration are important to care

and overall clinical outcome.For patients with decreased level of consciousness,

avoidance of oral feeding and oral drugs and elevation of the head of the bed to > 30 degrees may help

drenching of any fluid should never be done while holding tongue

Proper care taking of sheep while dipping.

OUTBREAK NEAR NURPUR AREA ON 20/3/2015

I along with my batch mate NISHANT THAKUR & with faculty member

Dr. ANKUR SHARMA from vet. medicine deptt., Dr. R.K.ASRANI from vet. pathology deptt., Dr. K.B.NAGAL from vet. Microbiology deptt. Visited three disease outbreak in sheep & goat flocks of gaddi’s near nurpur areas(distt. Kangra) on 20/3/2015.

PREPARATIONS MADE FOR THE VISIT

• Following commodities are arranged & packed by us, one day before leaving for attending the outbreaks.

• 20,21,22 gauze needles & 1 hypodermic needle• Heparinised, EDTA & new syringes• Examination gloves & sterile gloves packs• 1 Microscope, slides & coverslips• haemoglobinometer• Spirit swabs & cotton• Vials, BP blades , scissors• 2 stethoscopes, & 2 thermometer

SHEEP HERD AT REY

1.Outbreak – at Rey Owner name – Raju ram Total no. of animals- 250 goats & 200 sheep Total no. of mortality- 20 adult sheep (all death in last 12 days)

Clinical parameters of some selected animalsanimal Rectal temp. (f) Heart rate

(bpm)Resp.rate/min CMM

4month lamb 105o 150 86 Pale to pink

4year adult sheep

1040 104 44 Pale to pink

4 year adult sheep

1060 96 46 Pale to pink

OWNER-RAJU RAM WITH HIS HERD

3.Outbreak – at rey Few sheep revealed dry pulmonary ralesTentative diagnosis for pneumonia may be caused due

to drenching pneumonia as owner had done drenching of kerosene oil @2 t.s.f. for 6 days continuously as he believed it will cure diarrhoea .

Haemoglobin levels ranged between 4-7 g/dlDLC did not reveal any significant change

Blood parameters of third outbreak

ANIMALS HB(g%) PCV(%) DLC(%)

4month lamb 7 20 L-64, N-36, B-0, E-0

Young sheep 6 21 L-68, N-32, B-0, E-0

Adult sheep 4.2 19 L-78, N-22, B-0, E-0

Adult sheep2 5 19 -------------------------

EXAMINATION OF SOME SELECTED ANIMALS

Biochemical parameters of blood of third outbreak

ANIMAL TOTAL PROTEIN

BILIRUBIN AST ALT

Young sheep 6.1 0.04 440 23

4 month lamb 6.3 0.23 356 40

Adult sheep 8.0 0.02 333 28

Adult sheep 8.0 0.09 252 20

LUNG REMOVED WHILE POST-MORTEM OF AN AFFECTED SHEEP SHOWING ABNORMAL CHANGES IN RIGHT LUNG

EFFECTED LUNG

HISTO-PATHOLOGY REPORT OF LUNG SAMPLE COLLECTED FROM

THIRD OUTBREAKHyperplasia & thickening of bronchiolesAlveoli lumen packed with neutrophilsProminent Blood vessels injury Interlobular septa distended with exudatePlasma cells, giant cells infiltration

HISTO-PATHOLOGY REPORT OF LUNG SAMPLE COLLECTED FROM THIRD

OUTBREAKZone of neutrophilinfiltrations

Necrosed area

HISTO-PATHOLOGY REPORT OF LUNG SAMPLE COLLECTED FROM THIRD OUTBREAK

InterlobularSepta distendedWith exudate

Severe haemorrhage


Chronic purulentZones having neutrophil,Macrophages, fibroblasts


Plasma cells

Alveoli lumen filled with neutrophil


Hyperplasia& thickeningOf bronchioles

Lung tissue showing coagulative necrosis


Giant cell

Treatment advised at third outbreak

Susp. Nilzan 15ml p.o. & repeat after 3 week – for adult sheep & goat

Inj. Belamyl 2ml for 3 days i/m –repeat afte break of 3 days

Pwd. Agrimin forte , 2tsf/ adult animal

Inj. Enrofloxacin – to animal with pulmonary affection in standard doses & schedule

Boli. Ferritas one-fifth of bolus for 5 days – repeat after break of 5 days

HENCE IN CONCLUSION THERE IS ONLY MANAGEMENT ASPECT WHICH WE ADVISED

TO OWNER TO PREVENT ASPIRATION PNEUMONIA

• We also advised owner to not to give kerosene to animals.

• Do not drench any fluid while holding tongue.

• Keeping mouth upwards while dipping of sheep.

aspiration pneumonia in livestock :predisposing factors& remedy (with special reference to...

Health & Medicine

aspiration pneumonitis

aspiration of gastric

pathophysiology of pneumonia

gastric acid

kerosene petroleum products

low ph

clinical scenarios

phase peaks