VENTILATOR ASSOCIATED

PNEUMONIA

Dr Dushyanthi Perera

MBBS MD FRCA

Head of Critical Care and

Anaesthesia

Durdans Hospital

WHAT IS VAP ?

A nosocomial pneumonia associated with

mechanical ventilation or intubation that

develops 48 -72 hours after hospital

admission and which was not incubating at the

time of admission.

American Thoracic Society 2005

INCIDENCE

10 – 60 %

Most common nosocomial infection in ICU

(50% of ICU infections)

Incremental risk of VAP 1% per day of

ventilation

Tracheal intubation and ventilation 7 – 21 fold

increase the risk of pneumonia

WHY DO WE CARE?

3 fold - Increase in hospital stay

Increasing cost ( $ 40,000/ patient)

Chest 2002

Higher mortality ( patients die with rather than

of VAP)

CAUSATIVE ORGANISMS

Early Onset

H influenzae

Strp. Pneumoniae

Staph aureus

E coli

Klebsiella

Late Onset ( >5 d)

Pseudomonas

Acinetobacter

MRSA

Most strains responsible for early onset VAP are

antibiotic sensitive

Late onset VAP is usually Multi Drug Resistant

Am J Resp Crit Care 1998

Depends on

State of host defense

Virulence of the organism

Overwhelming inoculation

PATHOGENESIS

There are 3 pathways of entry into the lower

respiratory tract

Aspiration from the oropharynx and GI tract

(Commonest)

Direct inoculation ( biofilm embolisation

during suctioning and bronchoscopy )

Inhalation of bacteria ( contaminated

aerosols)

Aerodigestive colonization

Host factors Invasive devises/Sx Contamination medication

Aspiration

Tracheal colonization

Defense mechanisms compromised

Tracheobronchitis

Pneumonia Bacteremia GIT translocation

Inoculation/inhalation

Pathogenesis of VAP

Infect.med 20[5]248-259:2003

WHO IS AT GREATEST RISK ?

Extremes of age

Malnutrition

Immunocompromised

DM/ Liver disease

WHO IS AT GREATEST RISK?

Reintubation

Supine position

Impaired cough / depressed level of

consciousness

Oropharyngeal secretions

Presence of NG tubes and enteral feeding

Cross contamination by staff

HOW DO WE DIAGNOSE? 2 – 1 - 2

CXR – 2 consecutive days

New, progressive or persistent infilterate

Consolidation , opacity or cavitation

At least 1 of the following

Fever with no other recognized cause

WBC < 4,000 or > 12,000

At least 2 of the following

New purulent sputum or change in quality of sputum

Creps or bronchial breathing

Worsening gas exchange

Dyspnoea or tachypnoea

Am J Respir Crit Care Med.2005:171;388-416

ANTIBIOTICS ?

Prompt treatment with appropriate AB can

improve outcome

Over treating

Increases bacterial resistance

Overlooks other sources of infection

Increases costs

Am J Resp Crit Care Med 2005

ANTIBIOTIC SELECTION

Initial empiric and broad spectrum

Send gram stain and cultures prior to

commencing antibiotics

Rapid de-escalation once ABST is available

WHAT SAMPLE DO WE SEND?

Diagnostic method Quantitative culture

(CFU / ml )

Sensitivity (%) Specificity (%)

Tracheal aspirate Non quantitative 78 19

Tracheal aspirate

Qauntitative

> 10 6 69 80

Bronchio-alveolar

lavage

> 10 4 86 87

Protected brush

specimen

>10 3 82 92

CAN WE REDUCE IT ?

Modification of Specific ICU practices

Collaborative multidisciplinary approach

Intensive education of ICU personnel

( Doctors, Nurses and physiotherapists )

PREVENTION

Hand washing

Oral care

Elevate the head end of the bed 30 degrees

Patient turning

GI and DVT prophylaxis

Daily sedation holidays

Airway and ventilator management

Daily assessment on readiness to wean /

spontaneous breathing trial

HAND WASHING

Single most important and easiest method of reducing the transmission of pathogens

Use of waterless antiseptics acceptable and increase compliance

• Beginning and end of workday

• Before and after patient

contact

• After touching contaminated

surfaces

• Encourage patient’s to ask!

?.....

Health care worker button

Room poster

ORAL CARE

Dental plaque contains multiple pathogens

which rapidly shift from non pathogenic

organisms to GNB and Staph

Micro aspiration of oral secretions from around

the cuff occurs in all ventilated patients.

Good oral hygeine

WHY IS THERE NO CONSISTENCY IN ORAL

CARE?

Not given high priority

Anxiety on loosing the ETT

Optimal technique and frequency not determined

Best practice

Daily assessment of oral hygeine

Brushing or cleaning with swabs/ 12 hrs

Routine suctioning of mouth

Application of antibiotic solutions may cause

overgrowth of resistant bacteria

HEAD UP TILT – 30 – 45 DEGREES

Supine position is an independent risk factor

for death in all ICU patients

Major benefit in preventing aspiration

CDC recommendation

WHY ?

Help to reduced VAP

More comfortable

Easy to ventilate

Good for neurosurgical patients

OVER SEDATION

Leads to

DVT

Pressure ulcers

GI regurgitation and aspiration

VAP and Sepsis

Because

Difficult to monitor neurological status

Increases ventilator days

Increased diagnostic procedure

Longer ICU stay

SEDATION WEANING PROTOCOLS

Routine assessment of sedation levels

Setting sedation goals individualised for each patient

All infusions should be at the lowest rate required

IV bolus to supplement IV infusions when necessary eg physiotherapy, procedures

Every patient must be awakened daily unless contraindicated.

HOW ?

Wean off infusion by 10 – 25% daily till patient

wakes

Rebolus and restart infusion if patient becomes

symptomatic

New infusion rate should be lower than the

previous set rate

Goal is to decrease sedation

ENDOTRACHEAL INTUBATION

Causes mucosal injury and decreases mucociliary clearance

Decreases efficacy of cough

Increases mucus secretion

Provides resaviour for bacteria

Nasotracheal best avoided

Keep cuff pressure 25 – 30 cmH2O

Re intubation is a risk factor

Non invasive ventilation

SUCTIONING

Should be done regularly

N saline should not be used routinely

Can cause desaturation

Potentially may dislodge bacteria

Yankuer

Change daily

Rinse with N saline or sterile water

Leave to air dry

VENTILATOR CIRCUIT

Keep disconnection to the minimum

Leads to loss of PEEP and alveolar de-

recruitment

Expiratory condensation should be removed via

trap in the tubing

Humidify HME or Heated humidifiers

GASTRIC ALKALINIZATION

H2 blockers and proton pump inhibitors

decrease the incidence of stress ulcers

But colonisation increases with alkalinization

These organisms may gain access to the Resp

tract

Sucralfate

Enteral feeding better

ENTERAL FEEDING

Keep head end elevated

Verify NG tube placement routinely

No recommendations regarding continuous

versus bolus feeds

No recommendations regarding post pyloric

placements ( Naso jejunal)

SUMMARY

High index of suspicion

Cultures before antibiotics

Appropriate broad spectrum in high doses

Rapid de-escalation based on cultures

Non invasive ventilation whenever possible

Preventive measures

PREVENTION

Hand washing

Oral care

Elevate the head end of the bed 30 degrees

Patient turning

Early GI feeding and DVT prophylaxis

Daily sedation holidays

Airway and ventilator management

Daily assessment on readiness to wean /

spontaneous breathing trial

SEIZE THE OPPORTUNITY

Be The Agent of Change