ventilator associated pneumonia (vap) or hospital acquired pneumonia (hap)

PREVENTION & CONTROL OF

COMMON HAIS: THE BUNDLE

APPROACH ON HAP/VAPMarion Aurellado Kwek, MD, FPCP, FPSMID

17 Feb 2016

OUTLINE

Definitions

Pathophysiology of Nosocomial

Pneumonia

Risk Factors

Prevention

Prevention Bundles

DISCLOSURE

Received honoraria for lectures from Merck

Sharp Dohme

INTRODUCTION

Nosocomial pneumonia pneumonia

acquired while in a hospital

From the Latin word nosocomium:

“hospital”

Classically divided into:

Hospital-acquired pneumonia (HAP)

Ventilator-associated pneumonia (VAP)

Recently has also been applied to health

care–associated pneumonia (HCAP)

Mandell, Douglas and Bennett’s Principles and Practice of Infectious Diseases 8th Ed. 2015

INTRODUCTION

HAP is the leading cause of death among

HAIs, with estimates of HAP-associated

mortality ranging from 20 to 50%

Systematic review of published studies

found attributable mortality rate of 13%

for VAP Melsen et al. Attributable mortality of ventilator-associated pneumonia: a meta-analysis of

individual patient data from randomised prevention studies. Lancet Infect Dis. 2013 Aug;13(8):665-71

INTRODUCTION

Most cases of HAP occur outside of intensive care

units.

Highest risk for HAP is in patients on

mechanical ventilation (ie, VAP)

Steady decline in reported VAP rates in the US,

VAP from 0.0 to 4.4 per 1000 ventilator days

depending on the patient care location in 2012 2012 NHSN Annual Report

DEFINITIONS

DEFINITIONS (CLINICAL)

Hospital-acquired (or nosocomial) pneumonia (HAP)

Pneumonia that occurs 48 hours or more after admission

Not incubating at the time of admission

Ventilator-associated pneumonia (VAP)

Develops more than 48 to 72 hours after intubation.

Healthcare-associated pneumonia (HCAP)

Pneumonia in a nonhospitalized patient

With extensive healthcare contact

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

Am J Respir Crit Care Med Vol 171. pp 388–416, 2005

DEFINITIONS (CLINICAL)

Healthcare Contact

IVT, wound care, or IV chemotx within the

past 30 days

Residence in a nursing home or other long-

term care facility

Hospitalization in an acute care hospital

for two or more days within the prior 90

days

Attendance at a hospital or hemodialysis

clinic within the prior 30 days

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

Am J Respir Crit Care Med Vol 171. pp 388–416, 2005

http://www.idsociety.org/Guidelines/Patient_Care/IDSA_Practice_Guidelines/Infections_by_Organ_System/

Lower/Upper_Respiratory/Hospital-Acquired_Pneumonia_(HAP)/

http://www.idsociety.org/Guidelines/Patient_Care/IDSA_Practice_Guidelines/Infections_by_Organ_System/Lower/Upper_Respiratory/Hospital-Acquired_Pneumonia_(HAP)/

http://www.idsociety.org/Guidelines/Patient_Care/IDSA_Practice_Guidelines/Infections_by_Organ_System/Lower/Upper_Respiratory/Hospital-Acquired_Pneumonia_(HAP)/

DEFINITIONS (SURVEILLANCE)

To be discussed on 19 Feb 2016

Surveillance of HAI (Didactic) - Dominga

C. Gomez, RN and Dr. Dess Roman

Clinical diagnosis ≠ Surveillance Criteria

PATHOPHYSIOLOGY

PATHOPHYSIOLOGY

Histologic hallmark of VAP is heterogeneity

Lesions vary significantly in age and

severity

Dependent areas > nondependent areas

Different organisms can be cultured from

different lung segments of the same patient

in 25% to 37% of cases

Cultures of histologically benign–appearing

lung segments are often positive.


PATHOPHYSIOLOGY

Ventilated patients prone to repeated

microaspirations around the ET cuff

Microbiologic, structural, and humoral

factors combine to increase the risk of

pneumonia in critically ill patients


PATHOPHYSIOLOGY

Flora of the oral tract

rapidly shifts from

community respiratory

organisms (Strep,

Haemophilus) toward

“hospital-associated”

pathogens (S. aureus,

Enterobacteriaceae,

Pseudomonas, &

Acinetobacter sp.)

PATHOPHYSIOLOGY

Likelihood of

organisms being drug

resistant steadily

increases with time in

a hospital, exposure to

antimicrobials, and

severity of illness.

PATHOPHYSIOLOGY

OGT/NGT disrupt lower esophageal

sphincter + increase risk of aspiration of

gastric contents

ET disrupts normal ciliary clearance of

bronchial secretions + impairs patients’

capacity to cough.

Secretions pool above ET cuff and

intermittently seep around folds in the cuff,

particularly if the cuff is underinflated or if it

shifts during patient movement or

repositioning.

PATHOPHYSIOLOGY

Biofilm begins to form both inside and

outside the endotracheal tube within a day of

placement and serves as a bacterial reservoir

within the trachea and oropharynx.

Suctioning or instillation of aerosols through

the endotracheal tube can mobilize and

embolize bacteria from the biofilm into the

lungs.

Photo from slideshare

PATHOPHYSIOLOGY

Critical illness, poor nutrition, and

immobilization may increase patients’

susceptibility to infection.

These factors interact and reinforce with one

another to enhance the risk of

microaspiration and the likelihood that

pulmonary parenchymal colonization will

lead to invasive infection.

Lifted from Oliveira et al. Prevention of Ventilator associated pneumonia 2014

RISK FACTORS

RISK FACTORS

Factors that enhance risk of

aspiration increase the likelihood

of infection!!!

RISK FACTORS

Factors Examples

Mechanical factors •Emergency intubation,

reintubation, duration of

intubation

•Supine positioning

•Enteral feeding with OGT/NGT

•Use of paralytic agents

•Underinflation of ET cuff

Mental Status •CNS disease

•Level of consciousness

•Level of sedation

RISK FACTORS

Factors Examples

Bacterial bioburden

in the upper

respiratory and

orogastric tracts

•Duration of hospitalization

•Nasogastric intubation

•Prolonged antibiotic

exposures

•Use of PPIs or other gastric

acid suppressants

Increased handling

or breaking of the

ventilator circuit

Inhaled β-agonist therapy

RISK FACTORS

Factors Examples

Patient factors •Age > 70 yrs

•Preexisting lung disease

•Severity of illness

•Surgical patients, (burn and

trauma) higher VAP rates than

medical patients

Others •Intensive care staffing levels

•Transportation out of ICU for

diagnostic imaging or procedures

PREVENTION

Most prevention strategies are designed to

decrease volume of regurgitant secretions or

decrease the bacterial burden in and around

oropharynx and ET, or both

Many interventions lower VAP rates, but few

improve concrete outcomes such as duration of

ventilation, ICU length of stay, or hospital

mortality

PREVENTION BUNDLES

PREVENTION BUNDLES

Grouping multiple interventions together into

VAP prevention “bundles” may enhance their

effectiveness by exploiting synergies between

interventions or by enhancing their visibility,

immediacy, and hence performance by frontline

providers.

VAP prevention bundles have become a standard

of care in most hospitals

Recommendation Rationale Intervention Quality of

evidence

Basic practices Good evidence

that intervention

Decreases

average duration

of

MV, length of

stay, mortality,

and/or costs;

benefits

likely outweigh

risks

Use NIPPV in selected

populations

Manage pxs w/o sedation

whenever possible

Interrupt sedation daily

Assess readiness to

extubate daily

Perform spontaneous

breathing trials w/

sedatives turned off

High

Moderate

High

High

High

Summary of Recommendations for Preventing Ventilator-Associated Pneumonia

(VAP) in Adult Patients. SHEA/IDSA 2014

Recommendation Rationale Intervention Quality of

evidence

Basic practices Good evidence

that intervention

Decreases

average duration

of

MV, length of

stay, mortality,

and/or costs;

benefits

likely outweigh

risks

Facilitate early mobility

Utilize ET with

subglottic secretion

drainage ports for

patients expected to

require greater

than 48 or 72 hrs of MV

Change the ventilator

circuit only if visibly

soiled or

malfunctioning

Elevate the head of the

bed to 30–45

Moderate

Moderate

High

Low



Recommendation Rationale Intervention Quality

evidence

Special approaches Good evidence

that the

intervention

improves

outcomes but

insufficient

data available on

possible risks

May lower VAP

rates but

insufficient

data to determine

impact on

duration

of mechanical

ventilation,

length

of stay, or

mortality

Selective oral or

digestive

decontamination

Regular oral care with

chlorhexidine

Prophylactic probiotics

Ultrathin polyurethane

endotracheal tube cuffs

Automated control of ET

cuff pressure

Saline instillation before

tracheal suctioning

Mechanical tooth

brushing

High

Moderate

Moderate

Low

Low

Low

Low




evidence

Generally not

recommended

Lowers VAP

rates but ample

data suggest

no impact on

duration of

mechanical

ventilation,

length of stay,

or mortality

No impact on

VAP rates,

average duration

of mechanical

ventilation,

length

of stay, or

mortality

Silver-coated Ets

Kinetic beds

Prone positioning

Moderate

Moderate

Moderate




evidence

No

recommendation

No impact on

VAP rates or

other patient

outcomes, unclear

impact on

costs

Closed/in-line ET

suctioning

Moderate



PREVENTION BUNDLES

Involve implementation of various measures in

an attempt to reduce the incidence of VAP among

at risk patients

Measures often include educational programs,

technical measures, surveillance, and feedback

Practical way to enhance care

PREVENTION BUNDLES: EVIDENCE

Eight practices: hand hygiene, glove and gown

compliance, elevation of the head of the bed, oral

care with chlorhexidine, maintaining an ET cuff

pressure >20 cm H20, orogastric rather than

nasogastric feeding tubes, avoiding gastric

overdistention, and eliminating nonessential

tracheal suctioning

Rate of VAP decreased from 23 to 13 VAP

episodes per 1000 ventilator-days

No differences in total duration of mechanical

ventilation or the ICU and hospital death rates.

Bouadma L, et al. Long-term impact of a multifaceted prevention program on ventilator-associated pneumonia

in a medical intensive care unit. Clin Infect Dis. 2010;51(10):1115.

PREVENTION BUNDLES: EVIDENCE

Five interventions: semirecumbent position,

stress ulcer prophylaxis, DVT prophylaxis,

adjustment of sedation, and daily assessment for

extubation

Tested in 112 ICUs with 550,800 ventilator-days

VAP rate from a median of 5.5 cases per 1000

ventilator-days at baseline to a median of 0 cases

at 16 to 18 months after implementation

Berenholtz SM et al. Collaborative cohort study of an intervention to reduce ventilator-associated pneumonia in the intensive care unit.

Infect Control Hosp Epidemiol. 2011;32(4):305.

PREVENTION BUNDLES

Wide variability in their components and

definitions for adherence

No consensus about which care processes to

include

SUMMARY

Definitions

Pathophysiology

Risk Factors

Prevention

Prevention Bundles

CHALLENGE

Formulate bundles

Implement

Monitor

RCTs