Presentation on theme: "Ventilator Associated Pneumonia"— Presentation transcript:
1 Ventilator Associated Pneumonia Dr. Hany V. ZakiLecturer of Anaesthesia and ICU DepartmentAin Shams University
2 IntroductionMost patients who receive mechanical Ventilatory support for a protracted period develop microbial colonisation of the airwayA subset of these patients develops invasive infection requiring antibioticsVAP is the commonest ICU acquired infection
3 DefinitionPulmonary infection acquired in hospital, at least 48 hours after intubation and ventilation.Traditional clinical features (pyrexia, leucocytosis, pulmonary infiltrates on CXR, positive endobronchial sputum culture) may be inadequate.
4 Incidence and Risk Factors In 2002, an estimated 250,000 healthcare-associated pneumonias developed in U.S. hospitals and 36,000 of these were associated with deaths.For the year 2010, NHSN facilities reported more than 3,525 VAPs and the incidence for various types of hospital units ranged from per 1,000 ventilator days(Dudeck MA, Horan TC, et. al. National Healthcare Safety Network (NHSN) Report, Data Summary for 2010)Risk of VAP peaks at day 5. After 15 days the incidence plateaus and then declines - chronically ventilated patients have low rates of VAPHow do you diagnose VAP on top of ARDS? Similar clinical features. Post mortem studies show histologically proven VAP in 58% of ARDS patients.
5 MortalityMortality ranges from 20 to 41%, depending on infecting organism, antecedent antimicrobial therapy, and underlying disease(s)
6 COST OF VAPStrikingly, VAP adds an estimated cost of $40,000 to a typical hospital admission
7 Risk Factors:Duration of ventilation. 3% per day in first week, 2% per day in second, 1% per day afterSeverity of illness: high APACHE II scores (>16) correlate with risk of VAPHead injury or other cause of comaBurns and traumaAcute of chronic respiratory condition, ARDSMale sex and increasing age
8 Early vs LateEarly onset pneumonia occurs during the first four days of hospitalization and is often caused by Moraxella catarrhalis, H. influenzae, and S. pneumoniae.Late onset pneumonia are frequently gram negative bacilli or S. aureus, including methicillin-resistant S. aureus. Viruses (e.g., Influenza A and B or Respiratory Syncytial Virus), yeasts, fungi, legionellae, and Pneumocystis carinii.
9 VAP Etiology Staphylococcus aureus resistant organisms Most are bacterial pathogens, with Gram negative bacilli commonPseudomonas aeruginosaProteusAcinetobacterStaphylococcus aureusEarly VAP associated with non-multi-antibiotic-resistant organismsLate VAP associated with antibiotic-resistant organismEarly VAP (within 96 hours) is associated with non-multi-antibiotic-resistant organisms:E coliKlebsiellaProteusStreptococcus pneumoniaeHemophylus influenzaOxacillin sensitive Staphlococcus aureusLate VAP associated with antibiotic-resistant organisms:Pseudomonas aeruginosaOxacillin resistance Staphaerius and Acinetobacter
16 Prevention of Aspiration Preventive measures for VAPGeneral measures- Universal Precautions and Hygiene- FeedingKinetic therapy- Stress ulcer and DVT prophylaxis- Team ApproachPrevention of Aspiration- Head up- Cuff pressure of ETT- Avoid circuit manipulation- Drainage of secretionsDecontamination- Oral decontamination- GI decontamination- Silver ETT- Early weaning protocol- Daily sedation brakesEarly Extubation
17 Prevention of Aspiration Prevention of VAPPreventive measures for VAPGeneral measures- Universal Precautions and Hygiene- Feeding- Kinetic therapy-Stress ulcer prophylaxis- Team ApproachPrevention of Aspiration- Head up- Cuff pressure of ETT- Avoid circuit manipulation- Drainage of secretionsDecontamination- Oral decontamination- GI decontamination- Silver ETT- Early weaning protocol- Daily sedation brakesEarly Extubation
18 Hand washing What role does handwashing play in nosocomial pneumonias? cross colonization plays a major role in the spread of nosocomial pathogens.Gram negative bacilli are ubiquitous and often present in high concentrations in critically ill patients, the hospital environment and on the hands of hospital personnel. Especially problematic in the intubated patient is the ventilator tubing - high colony counts exist near the mouth piece.Washing hands before and after every patient contact is a very effective strategy to prevent cross contamination. Gloves should be worn by person’s with open lesions or dermatitis.Despite the Center for Disease Control in Atlanta’s recommendation to wash hands after every patient contact, most studies on hand washing find that <50% of the time that HCW follow this recommendation.
19 Wash hands or use an alcohol-based waterless antiseptic agent before and after suctioning, touching ventilator equipment, and/or coming into contact with respiratory secretions.The CDC recommends that hand washing occur before and after suctioning, whenever ventilator equipment is touched and/or if staff come in contact with respiratory secretions.CDC Guideline for Prevention of Healthcare Associated Pneumonias 2004AACN Practice Alert for VAP, 2007
20 Entral Feeding and VAPEnteral feeding may predispose to aspiration of gastric contents and the subsequent development of VAP.It has been suggested that placement of a post-pyloric feeding tube might reduce the risk of aspiration and VAP.A meta-analysis of seven studies found that post-pyloric feeding showed a trend toward lower incidence of VAP and mortality than gastric feeding. however, the differences were not statistically significant
21 The timing of initiation of enteral feeding has also been reported to be associated with the development of VAP. In a large retrospective multicenter analysis, early feeding (i.e., within 48 hours of onset of mechanical ventilation) was found to be associated with an increased risk of VAP, although ICU and hospital mortality were decreased in the early feeding group
22 Probiotics and VAPProbiotics are commercially available preparations of live non-pathogenic microorganisms administered to improve microbial balance resulting in health benefits for the host.Administration of probiotics has been advocated as a means of preventing a variety of infections including VAP in the ICU.
23 The potential beneficial effect of probiotics in prevention of VAP may be in their competition with VAP-producing microorganisms in the oropharynx and stomach.In addition, it has been suggested that the benefits of probiotics might be explained by their immuno- modulatory properties.Administration of probiotics was also found to be beneficial in reducing length of stay in the ICU and colonization of the respiratory tract by Pseudomonas aeruginosa.
24 Stress ulcer and VAPThe use of acid-suppressive medications and the subsequent increase in gastric pH allows bacterial growth in the stomach, increasing the risk of colonization in case of aspiration of gastric contents.A cohort study of more than 60,000 patients showed an increased risk of hospital-acquired pneumonia when acid-suppressive medications were used
25 However, no definitive recommendation can be provided about the use of acid-suppressive medications in relation to VAP in the ICU setting, and stress-ulcer prophylaxis is still suggested as part of the bundle treatments for VAP prevention published by the Institute for Healthcare ImprovementHerzig SJ, Howell MD, Ngo LH, Marcantonio ER: Acid-suppressive medication use and the risk for hospital-acquired pneumonia.JAMA 2009, 301:
26 Kinetic therapyImmobility of the intubated critically ill patient may impair mucociliary clearanceMechanical rotation of patients with 40° turns (kinetic therapy) may improve pulmonary function more than the improvement in function achieved via standard care (i.e., turning patients every 2 hours). Kinetic therapy is believed to improve movement of secretions and to avoid the accumulation of mucus in dependent lung zoneNakagawa NK, Franchini ML, Driusso P, de Oliveira LR, Saldiva PH, Lorenzi-Filho G: Mucociliary clearance is impaired in acutely ill patients. Chest 2005, 128:
28 Team ApproachThe prevention of VAP is a multidisciplinary team approach that should involve all health care givers from doctors, nurses, assistants, porters, housekeeping as all should act together with the same protocol to decrease the incidence of VAP
29 Prevention of Aspiration Prevention of VAPPreventive measures for VAPGeneral measures- Universal Precautions and Hygiene- Feeding- Kinetic therapy- Stress ulcer prophylaxis- Team ApproachPrevention of Aspiration- Head up- Cuff pressure of ETT- Avoid circuit manipulation- Drainage of secretionsDecontamination- Oral decontamination- GI decontamination- Silver ETT- Early weaning protocol- Daily sedation brakesEarly Extubation
30 Oral CareRole of oral care, colonization of the oropharynx, and VAP unclear – dental plaque may be involved as a reservoirLimited research on impact of rigorous oral care to alter VAP ratesSurveys indicate most nurses use foam swabs rather than toothbrushes in intubated patientsOral chlorhexidine washes decrease the incidence of VAPRole of oral care, colonization of the oropharynx, and VAP unclear – dental plaque may be involved as a reservoirLimited research on impact of rigorous oral care to impact VAP rates.Only 1 study has shown a decrease in VAP with the use of an oral chlorhexadine rinse, and that was done in preop CS patients. Too early to know if similar results will be obtained in other patients.Surveys indicate most nurses use foam swabs rather than toothbrushes in intubated patientsCDC Guideline for Prevention of Healthcare Associated Pneumonias 2004Grap M. Amer J of Critical Care 2003;12:
31 Silver ETTCoating the endotracheal tube with silver is theoretically attractive because silver has broad-spectrum antimicrobial activity in vitro, reduces bacterial adhesion to devices inA silver-coated tube has been developed with silver ions microdispersed in a proprietary polymer on both the inner and outer lumen, permitting ion migration to the tube surface to provide a sustained antimicrobial effect.The polymer may add to the antimicrobial activity of silver by blocking bacterial adhesion to the endotracheal tube
33 Selective Digestive Decontamination VAP often have an endogenous source of infection. Colonisation of the digestive tract and the oropharynx correlates with development of VAPSDD = Selectively eliminating potentially pathogenic organisms (not normal anaerobic flora) in the digestive tract and oropharynx with the aim of decreasing the incidence of VAP and it’s associated mortality
34 SDD usually involves: Potential benefits: Potential problems: Topical application of non absorbable agents (such as polymyxin B, tobramycin and amphotericin B) that have activity against G negative organisms and fungi.Initial use of broad spectrum IV antibiotics for 3-4 days, such as cefotazime.Potential benefits:Decreased VAP, improved mortality, less time in ITUPotential problems:Increased resistant organisms, cost, side effects.
35 Prevention of Aspiration Prevention of VAPPreventive measures for VAPGeneral measures- Universal Precautions and Hygiene- Feeding- Kinetic Therapy- Stress ulcer and DVT prophylaxis- Team ApproachPrevention of Aspiration- Head up- Cuff pressure of ETT- Avoid circuit manipulation- Drainage of secretionsDecontamination- Oral decontamination- GI decontamination- Silver ETTEarly Extubation- Early weaning protocol- Daily sedation brakes
36 HOB ElevationHOB at 30-45ºPositioning HOB in an elevated angle, if not medically contraindicated, is very important.Studies have shown, though, that even when no contraindication to HOB elevation is present, the rate of backrest elevation is low.CDC Guideline for Prevention of Healthcare Associated Pneumonias 2004 ATS / IDSA Guidelines for VAP 2005
37 Primary Route of Bacterial Entry into Lower Respiratory Tract Micro or macro aspiration oforopharyngeal pathogensLeakage of secretionscontaining bacteria aroundthe ET cuff
38 Cuff pressure and VAPCuff pressures of less than 20 cm H2O represent a modifiable risk factor for VAP. Usually cuff pressure is measured intermittently with the use of a manometer.The target cuff pressure level was cm H2O
40 Continuous Removal of Subglottic Secretions Use an ET tube with continuous suction through a dorsal lumen above the cuff to prevent drainage accumulation.ET tubes with an additional lumen for the removal of subglottic secretions have been found to decrease VAP in some studies by as much as 20 to 40%Extra cost of the tubes will more than be paid for by the decrease in VAP costs.CDC Guideline for Prevention of Healthcare Associated Pneumonias 2004 ATS / IDSA Guidelines for VAP 2005
42 Circuit manipulation and VAP Warm expired air condenses in ventilator tubing. Microbial growth occurs rapidly in the pooled condensate. Disconnection of the circuit and manipulation to drain the tubing can cause the contaminated condensate to dump directly into the lungs.
43 Condensation traps permit drainage without opening the circuit, preventing both microbial dump and contamination from the external environment.Opening the circuit for other procedures should be avoided. Accumulation of condensate can also be reduced by heat-moisture exchanger (HME).However, care must be taken not to allow patient secretions to dry, which can cause endotrachael and tracheostomy tube blockage
45 Early extubationThe risk of developing VAP increases with prolonged intubation, and re-intubation is a known risk factorSince the ETT is believed to be involved in the pathogenesis of VAP, many clinicians avoid intubation when possible.
46 The early use of NIV with the aim of avoiding intubation may be worth considering, particularly in fragile patients.Although a reduction in VAP incidence has not been demonstrated, the early use of CPAP reduced the need for ICU admission and ventilatory supportSquadrone V, Massaia M, Bruno B: Early CPAP prevents evolution of acute lung injury in patients with hematologic malignancy. Intensive Care Med 2010, 36:
47 Reduced administration of sedatives is associated with shorter ICU stays and fewer days of intubation. Although no data are currently available to prove that VAP occurrence is decreased by reduced sedative administration, daily suspension of sedative drugs has been suggested as a preventive measure.Blackwood B, Alderdice F, Burns KE, Cardwell CR, Lavery G, O'Halloran P: Protocolized versus non-protocolized weaning for reducing the duration of mechanical ventilation in critically ill adult patients. Cochrane Database Syst Rev 2010, 12:CD006904
49 Coppadoro A. , Bittner E and Berra L Coppadoro A *, Bittner E and Berra L. Novel preventive strategies for ventilator-associated pneumonia. Critical Care 2012, 16:210However, only a few have been demonstrated to be effective, and many others still need evaluation in large randomized clinical trials before definitive recommendations can be made.Among others, modifications to the ETT (e.g., subglottic secretion drainage systems, antimicrobial coating, alternative cuff shapes and materials), continuous maintenance of proper cuff inflating pressures, ETT secretion removal, patient positioning in the lateral horizontal position, kinetic therapy, and administration of probiotics are measures worthy of consideration and further study in the ongoing battle to reduce the rates of VAP.