VAP Prevention: What Is Really Fundamental?

Michael S. Niederman, MD

Chairman, Department of Medicine

Winthrop-University Hospital

Mineola, NY Professor of Medicine

Vice-Chairman, Department of Medicine

SUNY at Stony Brook

Prevention of VAP

• How Much of VAP Is preventable?

• Methods for VAP Prevention

– Recommended Strategies

• What are The Implications of The Zero VAP

Movement ?

Prevention of VAP

• How Much of VAP Is preventable?

• Methods for VAP Prevention

– Recommended Strategies

• What are The Implications of The Zero VAP

Movement ?

What Percent of Nosocomial Infection is Really

Preventable?

• 25 studies identified

• Global intervention vs. all types of NI led to a risk reduction of 11-55%

• Studies looking at specific infections found a reduction of 14-71%

– Greatest effect in catheter associated blood stream infections.

• Mean reduction rate of 56%, but up to 70%

– Reduction of VAP and surgical site infection rates was less

– Harbarth S, et al. J Hosp Infect 2003; 54: 258-266.

• To estimate the preventability of HAI in the US, used published

studies on prevention published in the last 10 years, and rated as

“good” quality by AHRQ

– 65-70% CAUTI and CABSI preventable

– 55% VAP and SSTI preventable. Only 2 good and 3 moderate quality studies

to evaluate. Feel that VAP reduction may be an OVERESTIMATE.

– Umscheid CA, et al. ICHE 2011; 32: 101-114.

Could We Do Even Better and Prevent ALL

VAP? IHI says “YES”

• From the IHI (Institute for Healthcare Improvement) Website

– No VAPs – It CAN Be Done!

Advocate Health Care; Oak Brook, Illinois, USA

– Reducing Ventilator-Associated Pneumonia: Changing Culture

Lee Memorial Health System, Cape Coral Hospital; Fort Myers, Florida, USA

• Absence of VAP for 200 days with implementation of a bundle. “ We celebrate each month that passes without a VAP”

• No mortality data.

• Berriel-Cass et al. Jt Comm Journal on Qual and Pat Safety 2006, 32: 612.

Can Prevention Efforts Really Lead to Zero

VAP?

• Compare incidence of VAP

(quantitative culture dx) in 45

month baseline period (n=856)

to 30 month multi-modality

intervention period (n=835). All

MV > 48 hours

• VAP rates reduced by 43%

(22.6 to 13.1 episodes /1000

vent days) BUT even with high

compliance to prevention , did

not drop to zero

• Bouadma L, et al. Clin Infect

Dis 2010; 51:1115-22

Interventions: HOB elevation, hand

hygeine, ETT cuff pressure > 20 cm

water, OG tube, oral chlorhexidine,

minimal tracheal suctioning

The Ventilator Bundle: Prevention ? Not

Elimination

• “Evidence-based” interventions

– Peptic ulcer disease prophylaxis

– Deep vein thrombosis prophylaxis

– Elevation of the head of the bed

– Awaken to follow commands

– Assess readiness to wean

• Applied in 112 ICU’s for 30 months and reported a 71% drop in VAP, with a correlation between compliance and VAP rates, but no measurement of secondary benefits – Used CDC VAP definition, applied by

infection preventionists

• Berenholtz SM et al. ICHE 2011; 32: 305-314.

Prevention of VAP

• How Much of VAP Is preventable?

• Methods for VAP Prevention

– Recommended Strategies

• What are The Implications of The Zero VAP

Movement ?

Recommended Prevention Strategies

• Systematic review of all randomized, controlled trials and reviews on prevention of VAP from 1980-2006.

• Recommended: – Orotracheal intubation

– Circuit changes if soiled or damaged, but not by schedule

– Change HME every 5-7 days, or as necessary

– Closed suction system (vs. open system)

– Subglottic secretion drainage

– HOB elevation of 45 degrees (questioned in some newer studies)

– CONSIDER: rotating beds, oral antiseptic rinse

• NOT recommended: in –line bacterial filters, iseganan

• NO recommendation: type of airway humidification, search for sinusitis, timing of tracheostomy, prone prosition, aerosol antibiotics, intranasal mupirocin, topical or IV preventive antibiotics – Muscedere J, et al: J Crit Care 2008; 23: 126-137.

Endotracheal Tube and Airway Interventions

• Biofilm on the inside of the ETT may add to VAP , and the mucus shaver has

been developed to remove it

– Studied in 6 sheep, 2 controls (routine suction), q 6 H

• Kolobow T, et al. Anesthesiology. 2005 ; 102:1063-5.

• Can remove biofilm/mucus layer, but will it prevent VAP?

• Endotracheal tube cuff modifications

– Intermittent subglottic secretion drainage.

– Cuff material and shape modifications (Polyurethane vs. PVC), shape (tapered). Lorente et al. Am J Respir Crit Care Med 2010; 182: 870-876.

• Ultrathin polyurethane HVLP (high volume, low pressure) cuffs reduce channel folds to prevent oral secretions reaching the lung

– Continuous adjustment of cuff pressure to 25 cm water pressure . Nseir et al. Am J Respir Crit Care Med 2011; 184: 1041-1047.

• Silver coated endotracheal tube: reduced VAP with no change in duration MV, ICU LOS or mortality. Kollef et al. JAMA 2008; 300: 805-813.

– Anti-bacterial peptide coated endotracheal tube: Cerashield

• NIV to promote early extubation, but may not prevent VAP. Girault C, et al. Am J Respir Crit Care Med 2011; 184: 672-679.

• Saline instillation prior to suctioning . Beneficial, but could also be harmful

Use of the “Mucus Shaver” To Prevent VAP

0.35 g mucus removed per use, led to lower

peak airway pressure on vent

Scanning EM ( TOP = shaver, MIDDLE=

New tube, BOTTOM= suction

The IHI Ventilator Bundle

• “Evidence-based” interventions to improve outcomes in ventilated patients, as part of the “Save 100,000 Lives Campaign”

– Peptic ulcer disease prophylaxis

– Deep vein thrombosis prophylaxis

– Elevation of the head of the bed

– Sedation vacation

– Daily weaning trial

• Applied in 35 ICU’s and reported a 44.5% drop in VAP, a correlation between compliance and VAP rates, and concluded that the “observations seem sufficiently robust” to support implementation

• Resar et al. Jt Comm Journal Qual Patient Safety 2005; 31: 243

Adherence With Ventilator Bundles Reduces

VAP Rates

• Found a correlation between compliance with bundles and VAP rates, BUT

– No dissection of the impact of each element

– No standardized, independently verified definition of VAP.

– Methods of defining adherence unclear

– No reported impact on other secondary endpoints: LOS, antibiotic use, mortality

• Resar et al. Jt Comm Journal Qual Patient Safety 2005; 31: 243

• How to best implement a bundle?

– Probably need a daily checklist

– Can enhance adherence to recommended processes of care in ICU

• Weiss et al. Am J Respir Crit Care Med 2011; 184: 680-686

•

Education Can Improve Nursing Knowledge of

VAP Prevention Tools

• European ICU nurses given a test on evidence-based

guidelines for VAP prevention

• 3329 questionnaires collected.

– Average score 45%

– 55% knew preference for oral intubation (vs. nasal)

– 35% knew to change vent circuit for each new patient

– 51% knew of subglottic secretion drainage

– 85% knew of semi-recumbent position to prevent VAP

• Better scores with seniority and larger ICU

– Labeau S, et al. J Hosp Infect 2008; 70: 180-185

Should We Be Using SDD?

• SDD is not a uniform intervention

• Meta-analysis supports a survival benefit of SDD to stomach and

oropharynx with 4 days of systemic antibiotics

• 4 Recent Prospective studies support mortality benefit to SDD

– BUT

• Benefits apply to only selected populations (trauma and surgical)

• Patients with very mild or very severe illness may not benefit

• Need to apply to ALL in ICU and this promotes the emergence of

resistance

• Increases rate of HAI after leaving ICU

• Increase in resistance after stopping SDD

• Maybe SOD or oral disinfection is just as beneficial (lower risk)

• With the advent of ventilator bundles, may get a reduction in VAP

that cannot be further reduced with SDD

Why SDD Should Not Be Used Routinely In All

ICU’s and ICU Patients

Brar NK, Niederman MS. Curr Resp Med Rev 2010; 6: 45-51

Key Points For Preventing VAP

• Identify key factors for prevention in your hospital and implement

in the form of a bundle

– Head of bed elevation may NOT be important (maybe head down to

promote secretion drainage)

• Focus prevention on: early weaning, daily interruption of sedation,

attention to the endotracheal tube and airway interventions

• Oral chlorhexidine and bundle may be as valuable as SDD

• Consider: prophylactic antibiotics for emergent intubation, early

tracheostomy if long-term intubation likely ( trend to benefit, but

not significant; Terrragni et al. JAMA 2010; 303: 1483-1489) ,

non-invasive ventilation to facilitate early weaning

• To implement a bundle, need education program, daily checklist,

monitoring of adherence and VAP rates

Prevention of VAP

• How Much of VAP Is preventable?

• Methods for VAP Prevention

– Recommended Strategies

• What are The Implications of The Zero VAP

Movement ?

VAP Rates as a Quality Indicator

• Arguments in Favor

– VAP adds to morbidity , mortality and cost and thus reducing

rates could have value

– VAP is largely preventable

– Prevention requires a team approach and requires alterations in

processes of care that are an indirect reflection of quality.

Therefore reduced rates= improved quality

– In the US, VAP may be considered a medical error, and possibly

not reimbursed

• This presumes that ALL VAP is preventable

• The advent of IHI and ventilator bundles has reinforced the

idea that VAP rates should be able to be reduced to ZERO in

good patient care centers

VAP Rates as a Quality Indicator

• Arguments against

– To use rates as a quality indicator requires a uniformly

accepted , reproducible and accurate definition of VAP

• The widely used NNIS definition does not fit these criteria

– Case mix varies from hospital to hospital ,and thus VAP rates

vary independent of quality

– Not all VAP is preventable: patient factors are not controllable,

we can only impact processes of care

– Reduction in VAP rates with current strategies has usually not

led to other secondary benefits

– Maybe better to target processes of care or measureable

outcomes (mortality, LOS, duration MV, antibiotic use)

Problems With Public Reporting of VAP Rates

• Pressure of public reporting promotes under-reporting of VAP rates

– May be reluctant to test aggressively for VAP

– Hospitals with (falsely) low rates may be lulled into thinking things are fine

– Hospitals with (falsely) high rates may get penalized in “pay for performance” atmosphere, and end up with fewer resources to help patients.

– Klompas M, Platt R. Ann Intern Med 2007; 147: 803-805.

VENTILATOR BUNDLES: THE NEW

EMPEROR??

How Can Ventilator Bundles Lead to Zero VAP

With All These Problems?

• Ventilator Bundle elements are not always logical

– Why DVT and GI bleed prophylaxis?

– Is all the benefit due to wakening and weaning?

• HOB elevation may not be worthwhile

– Many proven prevention strategies not included

• Why not oral care?

– Conflicting elements: daily awakening may promote self extubation , reintubation and add to risk

• VAP may not always be preventable

– Case mix problem

• The Reduced VAP rates reported with bundles may not be believable

– Inaccurate clinical definition, pressure of public reporting

– Surveillance itself may change reported rates

– Reduced rates NOT confirmed by secondary endpoints: antibiotic use, duration MV, LOS, cost, mortality

Influence of Diagnostic Method on The

Incidence of VAP

• Compare Dx of VAP in 53

patients with clinical

suspicion of VAP using

ET and BAL • Aspirate over dx VAP : 89%

vs. 21% with clinical VAP

• Model the potential effect

of VAP incidence and

antibiotic use with dx by

ETA or BAL

– Predicted that use of BAL

would reduce VAP by 76%

and antibiotic use by 30%

•

Morris AC, et al. Thorax 2009;

64:516-22

Have We Eliminated VAP by Calling it VAT?

• 2060 ventilated patients. Outcomes of VAT and VAP were similar:

ARE THEY REALLY THE SAME DISEASE WITH VAT

MASKING THE VAP DIAGNOSIS?

• Dallas J, et al. Chest 2011; 139:513-518

Problems with VAP Definition Are Leading to a

New Term (VAC) With No Radiograph Needed!

• CDC definition of VAP: requires a radiographic, signs and symptoms, and

laboratory assessment

• Limits of using the current definition

– Subjective interpretation of clinical signs and X-ray. Interobserver

variability. Klompas, AJIC 2010; 38: 237

– Diagnostic method: BAL vs. endotracheal aspirate

– Do antibiotics get started WITHOUT getting cultures, or for VAT?

• The concept of Ventilator Associated Complications (VAC)

– Being explored by CDC, but may not be infection-specific or preventable

– Worsening oxygenation: Measure serial PaO2/FiO2 ratio. Need at least

2 days baseline stability and FiO2 increase > 0.2 or PEEP > 3, for 2

days

– IVAC if : fever or hypothermia, leukocytosis or leukopenia, AND a new

antibiotic is started for at least 4 days

– IVAC: Is this VAP + VAT+ a lot of other things (not pneumonia)?

What Other Approaches Are Possible?

• Aim for preventability

• Our current model

– May provide little motivation to improve care

– High performers are satisfied with status quo

– Low performers discredit the adjustment model

• Link care actually received to outcomes

– How many patients with an adverse outcome had an

appropriate prevention efforts?

• Those without prevention effort are defined as avoidable

harm

• Pronovost P and Colantuoni E .JAMA 2009; 301: 1273-5

Focus on Modifiable Risk Factors: Processes of

Care that Can Be Monitored and Are Relevant

• Structure-related quality measures

– Infection surveillance system in place, feedback about surveillance data, staff eduction, nurse: patient ratio, water supply with HEP filters, alcohol-based hand rubs for hygeine, staff expertise, ventilator circuit humidification (HME), endotracheal suction devices

• Process-related quality measures

– Use of non-invasive ventilation, route of intubation (frequency of nasal vs. oral) ,reintubation rates, frequency of vent circuit changes, head of bed elevation, subglottic secretion drainage, timing of tracheostomy, transport from ICU (some may be modifiable) , mobilization of patients, compliance with hand hygeine, glycemic control, early enteral feeding, transfusion, SDD, mouth care, sedation and weaning protocols

• Outcomes other than VAP rate:

– LOS, attributable mortality, attributable costs

• Uckay I, et al. Clin Infect Dis 2008; 46: 557.

Using VAP Rates As An Indicator Of Quality Is

Dangerous

• Presumes that all VAP is preventable

– Therefore VAP is a medical error

– Assumes that hospital quality can be reflected by VAP rates

• The advent of IHI and ventilator bundles has reinforced the idea that VAP rates should be able to be reduced to ZERO in good patient care centers

– Ignores the differences in case mix between hospitals

• If VAP is considered a reflection of poor quality of care, hospitals will be tempted NOT to treat indigent, and other high risk patients with NON-MODIFIABLE risk factors

• Pressure of public reporting promotes under-reporting of VAP rates

– Hospitals with (falsely) low rates may be lulled into thinking things are fine

– Hospitals with (falsely) high rates may get penalized in “pay for performance” atmosphere, and end up with fewer resources to help patients.

– Klompas M, Platt R. Ann Intern Med 2007; 147: 803-805.

• Will eliminate research into VAP

– How and why study a disease that should not be present?