Nosocomial Pneumonia

Hospital Acquired, Ventilator Associated, Healthcare Associated Pneumonia

Outline and Goals

• Learn Definitions of types of NP

• Learn Pathogenesis/Epidemiology

• Learn Diagnosis

• Learn Initial Management

• Learn Impact of NP

• Learn Prevention of NP

Hospital Acquired Pneumonia

• “occurs 48 hours or more after admission”

•“was not incubating at the time of admission”

• Guidelines for the Management of Adults with Hospital-acquired, Ventilator-associated, and Healthcare-associated Pneumonia

•American Thoracic Society and the Infectious Diseases Society of America•Am J Respir Crit Care Med Vol 171. pp 388–416, 2005

Ventilator Associated Pneumonia

• > 48 to 72 hours on closed ventilator

• Non-Invasive Ventilation not a factor

Healthcare-Associated Pneumonia

• Nursing Home/LTCH resident

• >48Hr hospital stay in past 90 days

• Within past 30 days had:

• Wound Care or I.V. Therapy

• HD or Hospital Clinic visit

Pathogenesis

• Colonization of Lower Respiratory Tract (LRT)

• Vulnerable Host Defenses

Colonization LRT

• Microaspiration

• Introduction by devices (catheters, aerosolized material)

• Direct Leakage around ETT cuff

• Biofilm

Vulnerable Host Defenses

• Cellular/Humoral Defenses

‣ Immunosupressed, infected, surgery, organ failure, recent antibiotics, frequent transfusions of blood/blood products

• Mechanical Defenses

‣ Turbinates, vocal chords, ciliated epithelium, cough, acidified stomach

VAP Incidence

• 90% of the HAP in the ICU is VAP

• Incidence increases over time but risk highest early in vent course

• 3%/day from day 0 to 5, 2%/day from day 5-10, 1%/day after

• So risk starts at minute zero of intubation

Microbiology

• Frequently polymicrobial

• Multidrug Resistance (MDR) Problem

• Similar spectrum in all types NP

• Viral/Fungus very uncommon

Aerobic Gram Negatives

• Pseudomonas

• Klebsiella

• Acinetobacter

• Very Institution Specific

• Stenotrophomonas

• Legionella

Gram Positives

• Most commonly staph

• ICU in USA MRSA>MSSA

• Pneumococcus much less common

Risk for MDR

• HCAP risks

• >5 days since admission

• Antibiotics in past 90 days

• Immunosupressed

• High MDR rate in hosp/unit

Suspect Pneumonia if:

• New/Progressive CXR findings

• Clinical Infection Findings

• Fever, Leukocytosis, Leukopenia

• Respiratory Findings

• Purulent Sputum, Deoxygenation

Additional Clinical Clues

• Mental Status Change in Elderly

• New Crackles, Egophony

• Worsening Dyspnea or Cough

• Increased Need for Vent Support

• Increased Suction Requirements

Diagnosis: Cultures

• Sensitivity and specificity poor with clinical criteria alone

•especially with vented patients

• CXR+ and 2/3 clinical findings present

•sensitivity 69%

•specificity 75%

•Fabregas et al, Thorax 1999;54:867–873

Lower Respiratory Cx

• Bronchoscopy or ETT Aspiration

• Both good NPV (>90%)

• ETT aspirate can’t distinguish colonizers; may lead unnecessary abx

• Bronch invasive; not as accessible

Blood Cultures

•Always obtain

•Limited sensitivity (25%)*

•May be extrapulmonary so limited specificity*

•For non-vented patients may be only accessible culture

• *Luna CM et al, Chest 1999;116:1075

Microbiological Diagnosis

• Culture if clinically suspect NP, BEFORE antibiotics if possible

• Always try LRT Cx or Sputum

• Always blood culture

• Avoid unnecessary sampling to prevent unneeded abx and MDR

Initial Management

• Empiric early therapy with APPROPRIATE antibiotics

• Do not delay therapy for microbiological sampling

• Delay in therapy has higher mortality

Appropriate Antibiotics?

• HAP with no MDR risks?

• Becoming less common, but can use

• Ceftriaxone

• Ampicillin/sulbactam

• Moxifloxacin

Appropriate Antibiotics

• Otherwise should start with

• Antipseudomonal therapy

• Cefepime, Imipenem, Meropenem

• plus

• MRSA Therapy

• Vancomycin, Linezolid

Impact of HAP/VAP

• 25% ICU infections HAP

• Most common cause for antibiotic use in ICU - likely contributor to MDR

• HAP extends LOS by 7-10 days

• Mortality ranges 30 - 70%

• Cost of one case $40,000

Prevention

•We give patients this.

•The chief complaint on entering the health care system is never:

•“I have ventilator associated pneumonia”

•Everyone who touches the patient has a responsibility to prevent it.

Hand Washing

• Before and after every patient contact however small

• Dirty hands are lethal weapons

• Soap/Water 30 seconds

•(“Happy Birthday” or “ABC” twice)

• Alcohol Scrub acceptable

Circuit Integrity

• The ventilator tubing (called “circuitry”) is changed weekly

• More frequent changes do not reduce VAP

• Avoid opening it unnecessarily - use in-line suction catheter if possible

Patient Positioning

•Elevate Head of Bed (HOB) to 30-45˚

•Reduces clinical rate from 34% to 8%*

•Reduces culture rate from 23% to 5% *

•Every vented patient should have HOB >30˚at all times from the start unless absolute contraindication

• Lancet 1999 Nov 27;354:1851

Judicious Intubation

• Cannot get VAP if not on the Vent

• NIPPV good for CHF, COPD

• Not good for AMS, Secretions

• Do not delay necessary intubations

Removal of Ventilator

• Cannot get VAP if not on the Vent

• Patients need aggressive weaning

• Includes daily waking from sedation

• Includes daily wean trials if meets criteria (see weaning protocol)

IHI Bundle

1.HOB Elevation

2.Daily Sedation Vacation

3.Daily Wean Trials

4.DVT Prophylaxis

5.GI Ulcer Prophylaxis

• Some institutions self-report VAP rates of 0% after adopting IHI bundle

• Only 3/5 recommendations directly impact VAP

• HAP/VAP/HCAP significant cause of hospital/ICU Morbidity

• Significant cost in resources, patient safety and likely mortality

• Significant public health problem; possibly fueling development of MDR

Summary

Summary

• Once suspect diagnosis must attempt to confirm with cultures

• Empiric antibiotics must be started quickly

• Coverage for MRSA and Pseudomonas in most cases is warranted

Summary

• Rapid de-escalation of antibiotics

• Narrow if pathogen known

• Remove if improves and cultures negative

Summary

• Prevention Essential

• Handwashing and Infection Control

• HOB elevation

• Avoid unnecessary intubation

• Wake and Wean Aggressively

• Maintain Circuitry Integrity