VENTILATOR ASSOCIATED PNEUMONIA (VAP)
Dr.Tinku JosephDM Resident
Department of Pulmonary MedicineAIMS, Kochi
Email: [email protected]
Ventilator-associated pneumonia (VAP) is a type of HAP that develops more than 48 to 72 hours after endotracheal intubation.
Hospital-acquired (or nosocomial) pneumonia (HAP) is pneumonia that occurs 48 hours or more after admission and did not appear to be incubating at the time of admission.
Definition- “Know the enemy”
(ATS/IDSA) guidelines 2005
Healthcare-associated pneumonia (HCAP) is defined as pneumonia that occurs in a nonhospitalized patient with extensive healthcare contact, as defined by one or more of the following:
Intravenous therapy, wound care, or intravenous chemotherapy within the prior 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
Definition- “Know the enemy”
(ATS/IDSA) guidelines 2005
Definition- “Know the enemy” Typically in studies, patients are only included if
intubated greater than 48 hours Early onset= less than 4 days Late onset= greater than 4 days
Endotracheal intubation increases risk of developing pneumonia by 6 to 21 fold
Accounts for 90% of infections in mechanically ventilated patients
American Thoracic Society, Infectious Diseases Society of America. Guidelines for the management of adults with hospital-acquired, ventilator-associated,
and healthcare-associated pneumonia.
VAP- Risk Factors
VAP- Risk Factors
Age >70 years Severe Illness Underlying Lung Disease Depressed Mental Status Immunocompromising conditions Viral Respiratory Tract Infection Treatments Agents that increase gastric pH (H2 blockers,
antacids, proton pump inhibitors) Previous antibiotic exposure, particularly to third-
generation cephalosporins. Paralytic agents
Host Factors
VAP- Risk Factors
Intensive Care Setting Use of Antimicrobial Agents Contaminated hands Contaminated Equipment
Colonisation
VAP- Risk Factors
Colonisation
VAP- Risk Factors
Mechanical ventilation Tracheostomy Use of a Nasogastric Tube Supine Position
Factors that facilitate reflux & aspiration into the lower RT
VAP- Risk Factors
Abdominal or thoracic surgery
Immobilisation
Factors that impede normal Pulmonary Toilet
Why in ICU patients ??
VAP Types
Early v/s late VAP
VAP occurs in 10 - 65% of all ventilated patients Crit Care Clin (2002)
Incidence increases with duration of MV 3% /day for first 5days, 2%/day for 6-10days and 1%/day after 10 days.
Mortality rate is 27% &43%with antibiotic resistant organism.
critical care societies collaborative(CCSCs) Mortality rate in VAP caused by Pseudomonas or
Acinetobacter is as high as 76% Crit Care Med (2004)
Incidence
Increases ventilatory support requirements and ICU
stay by 4.3 days Increases hospital LOS by 4 to 9 days
Increases medical cost
Chest 2002;122:2115 Critical Care Medicine 2005;33:2184-93
Incidence
Pathogenesis
Bacteria enter the lower respiratory tract via following pathways:– Aspiration of organisms from the oropharynx and
GI tract (most common cause)– Direct inoculation– Inhalation of bacteria– Haematogeneous spread
ASPIRATION- primary route of bacterial entry into LRT
ENDOTACHEAL TUBE Holds the vocal cords open-predispose to micro & macro aspiration of colonized bacteria from oropharynx to LRT.Leakage of secretion containing bacteria around the ETT cuff.
• NGT OR OROGASTRIC TUBE • Interrupt gastro-esophageal sphincter leading
GI reflux and aspiration. Increase oropharyngeal colonization, stagnation of oropharyngeal and nasal secretion.
Pathogenesis
Inhalation of aerosols containing bacteria : -Contaminated RT equipment -From other patients/ healthcare personnel's -Inadequate disinfection/sterilization technique -Contaminated solutions/waterDirect contact:
-Cross Contamination (Hands)
Pathogenesis
Pathogenesis
Pathogenesis
VAP Pathogenesis
MDR Pathogens
• Host risk factors for infection with MDR pathogens include :
Receipt of antibiotics within the preceding 90 days Current hospitalization of ≥5 days High frequency of antibiotic resistance in the community
or in the specific hospital unit. Immunosuppressive disease and/or therapy Severe septic shock. Patients with HCAP are at variable risk for infection due
to MDR pathogens.
Diagnosis
NO UNVERSALLY ACCEPTED GOLD STANDARD DIAGNOSTIC CRITERIA!!!!!
DIAGNOSIS
CLINICAL
MICROBIOLOGICAL
RADIOLOGICAL
Clinical presentation
Clinical Pulmonary Infection Score (CPIS)
CPIS
How do we diagnose ? 2-1-2
Microbiological diagnosisATS/IDSA
QUALITATIVE
CLINICAL CRITERIA
Respiratory secretion sampling
Bronchoscopic methods
BAL V/S PSB
Non Bronchoscopic Methods
Bronchoscopic V/S Blind techniques
Difference between VAP and VAT
Role of biomarkers as diagnostic and prognostic markers of VAP
RADIOLOGIC DIAGNOSIS
INFILTRATES
SOLITARY DIFFUSE NEW INFILTRATES
Radiological evidence of pneumonia
THINK BEFORE
LABELLING IT AS VAP!!
Radiological mimics of pneumonia in ICU patients
Chemical/Aspiration pneumonitis Atlectasis/lung collapse LVF ARDS Pleural effusion Pulmonary embolism Pulmonary hemorrhage Lung contusion Infiltrative tumor Radiation Pneumonitis Drug reaction Cryptogenic organizing pneumonia
How will u treat VAP?
BEFORE CHOOSING ANTIBIOTIC, keep in mind on the following issues: Risk factors of the patient Was it early or late onset Virulence of organism Antibiotic resistance Cost
TREATMENT PROTOCAL Initial therapy is empiric Start when VAP is suspected, Don’t delay Individualize to institution- Hospital epidemiologic data Drug cost and availability Individualize to patient-
-Early onset versus Late onset of VAP -Prior antibiotic use
-Underlying disease Renal, liver disease etc -Surveillance cultures -Use gram stain results if possible
Choice of antibiotic
Specific anti microbial considerations (MRSA)
Linezolid or Vancomycin is a necessary first choice for antistaphylococcal coverage .
Should be discontinued if MRSA is not isolated. Linezolid – 600 mg twice daily intravenously (IV; or
orally if or when the patient is able to receive oral medications)
Vancomycin – 15 to 20 mg/kg (based on actual body weight) IV every 8 to 12 hours for patients with normal renal function,
Alternative to Linezolid and vancomycin -: Clindamycin (600mg IV TID)
Telavancin: activity against MRSA. 10mg/kg IV OD. Other agents-: Daptomycin, Ceftaroline. Tigecycline-: It has been approved by the FDA for
skin and skin structure infections and intraabdominal infections caused by MRSA
Specific anti microbial considerations (MRSA)
Specific anti microbial considerations (MSSA)
If a sputum culture reveals MSSA empiric therapy for MRSA should be replaced with nafcillin (2 g IV every four hours) or oxacillin (2 g IV every four hours).
Monotherapy/ Combination therapy Avoid cephalosporins monotherapy in ICU settings -:
Presence of ESBL producing Enterobacteriaceae. Resistant organism.
Carbapenams-: Most reliable agent.Eg: meropneam, imipenam- cilastin, Ertapenam.
Doripenam-: Not much preferred.
Specific anti microbial considerations (Gram negative pathogens)
Specific anti microbial considerations (Legionella)
Patients who have diabetes mellitus, renal disease, structural lung disease, or have been recently treated with glucocorticoids may require coverage for Legionella spp (azithromycin or a fluoroquinolone).
Specific anti microbial considerations (Anaerobes)
Patients who have aspirated or had recent abdominal surgery may warrant coverage for anaerobes (clindamycin, beta-lactam-beta-lactamase inhibitor, or a carbapenem).
Specific anti microbial considerations
Antiinflammatory effects of macrolides Studies have shown good results in VAP (faster
resolution) Extended infusions: can potentially provide effective
therapy for pathogens with higher minimum inhibitory concentrations (MICs), may impede the emergence of resistance, and potentially provide a pharmacoeconomic benefit.
Aerosolized antibiotics
Aerosolized colistin, polymyxin, or aminoglycosides may be considered as potential additional antibiotics in patients with multidrug-resistant gram-negative bacilli.
Aerosolization may increase antibiotic concentrations at the site of infection and may be particularly useful for treatment of organisms that have high MICs to systemic antimicrobial agents.
VAP- Duration of treatment
The duration of therapy should be based upon the clinical response.
The standard duration of therapy in the past was 14 to 21 days in part because of a concern for difficult to treat pathogens (eg, Pseudomonas spp).
Treatment failure
Prevention of VAP
Specific practices have been shown to decrease VAP Strong evidence that a collaborative,
multidisciplinary approach incorporating many interventions is paramount
Intensive education directed at nurses and respiratory care practitioners resulted in a 57% decrease in VAP
Crit Care Med (2002)
Prevention of VAP
Conventional Infection control Aproach
Design of ICUAdequate space, lighting, proper function of ventilatory system, facilities for hand washing, Isolation room.StaffingEducation, Adequate number, quality, importance of personal cleanliness and attention to asceptic procedures.Hand washing and Hand rubbing with alcohol based solution.
Prevention of VAP
Conventional Infection control Aproach
Periodical bacterial monitoring policy. Specific prophylaxis- • use gloves, gown, mask. • Use of NIPPV • Minimize duration of MV, checking daily for readiness
to weaning/extubation• (Text book of criti care med. 5 the Edit.
MitchellP.FinkSHOEMAKER)
Prevention of VAP
EFFECT OF VAP BUNDLE CARE
VAP BUNDLE (VAP reduction rate44.5%)
VAP bundle(4) originated in 2005 from INSTITUTE OF HEALTH CARE IMPROVEMENT(IHI) & CDC
IN 2010 FIFTH COMPONENT DAILY ORAL CARE WITH CHLORHEXIDINE IS ADDED. 2011 -: Subglottic suction (criti. care 2012 vol. 40,no.1)
Prevention of VAP
Society of Healthcare Epidemiology (SHEA) and the Infectious Diseases Society of America (IDSA) issued updated practice recommendations to reduce the risk of ventilator-associated pneumonia (VAP) 2014
Patient positioning The supine position is an
independent risk factor for death in all ICU patients
HOB elevation to 30-45 degree especially during feeding prevent aspiration and 34% reduction in VAP (Lancet.nov.1999;354,1851-1858)
CDC recommends HOB 30-45° unless contraindicated
Prevention of VAP
Contraindications
Hypotension MAP <70Tachycardia >150CI <2.0Central line procedure Posterior circulation strokes Cervical spine instability use reverse trendelenburgSome femoral lines i.e.: IABP no higher than 30 degrees use reverse trendelenburgIncreased ICP, No higher than 30 degrees avoid hip flexion Proning
Reverse Trendelenburg
In full reverse Trendelenburg the foot of bed will read -12 degrees
Angle of head elevation is approximately 20 degrees (not 30 degrees) when at -12
Evaluate the individual clinical situation to assess if the patient can tolerate the addition of a small amount of Fowlers angle which may flex the hip
Daily Sedative Interruption and Daily Assessment of Readiness to Extubate
OVERSEDATION• Predisposes patients to:– Thromboemboli– Pressure ulcers– Gastric regurgitation and aspiration– VAP– Sepsis
• Consequences include:– Difficulty in monitoring neuro status– Increased use of diagnostic procedures– Increase ventilator days– Prolonged ICU and hospital stay
Daily Wake Up
Every patient must be awakened daily unless contraindicated!
Daily weaning assessments reduce the duration of mechanical ventilation.
Wean infusion to off in increments of 10-25% daily in order to perform a clinical assessment
Rebolus and restart infusion if the patient becomes symptomatic. Your new continuous IV dose should be lower than what you began with
Consider implementation of a sedation scale such as the Richmond Agitation Sedation Scale (RASS) scale to avoid over sedation.
Goal is to decrease sedation
Daily Wake Up
Stress ulcer prophylaxisSucralfate, H2 receptor blocker, proton pump inhibitor Increases gastric PH and minimize bacterial colonization that reduces the risk of VAP and GI bleeding
Sucralfate Decreases the VAP rate but increases the risk of GI bleeding by 4%.H2 receptor blockers/PP inhibitors Increase rate of VAP by increasing gastric PH leading to colonization of bacteria and decreases the risk of GI bleeding.
H2 receptor blocker, PP inhibitor preferred over sucralfate
Am J Respir Crit Care Med. 2005;171(4):388-416
Deep Venous Thrombosis (DVT) Prophylaxis
There is increase risk of thomboembolism in mechanically ventilated patient.There is no any data association between DVT prophylaxis and decreasing rates of VAP.VAP rates decreased most dramatically in hospitals where all elements of the Ventilator Bundle were implemented, including this one.
Chest. 2004;126(3 Suppl):338S-400S.
Daily oral care
Dental plaque- due to absence of mechanical chewing and the saliva and they are reservoir for potential pathogens that causes VAP.Mechanical interventionTooth brushing , Rinsing of oral cavity to remove dental plaquePharmacological intervention0.12% CHLORHEXIDINE ORAL RINSE 15 ml twice daily Am J Crit Care. 2009 Sep;18(5):428-437
Oral decontamination 2%genta+2%Colistin+2%Vanco paste QID Selective decontamination of digestive
tract(SDD)- 2%polymyxin+tobra+Amphotericine paste oral
application QID. Solution 100mg poly+80mg tobra+500mg ampho
QID throu NG. IV Cefuroxime 1.5g TID first 4days.
Daily oral care
Promotes growth of resistant bacteria
Daily oral care• Best Practice??–Daily assessment to determine oral health–Brush q 12 hours to prevent plaque–Oral cleansing q 2-4 hours to promote healing
and maintain integrity of oral tissues–Use of an alcohol-free, antiseptic oral rinse to
prevent or reduce bacterial load of oropharynx–Routine suctioning of mouth to manage oral
secretions and minimize risk of aspiration–Use of a moisturizer Am J Crit Care (2005)
Gastric volume monitoring
standard clinical practice to monitor the patient's gastric residual volume at regular intervals and/or prior to increasing the infusion rate of gastric tube feeding
Hoping to minimize the risk of unrecognized gastric fluid accumulation and vomiting resulting in pneumonia
several studies have shown that measurement of gastric residuals correlates poorly with aspiration risk and is associated with a decrease in calorie delivery.
A randomized trial has shown that the rate of VAP was not higher in patients who did not undergo monitoring of gastric residuals.
Gastric volume monitoring
Not recommended now a days
Probiotics
Not effective in preventing VAP as per various randomized controlled trials.
Most commonly used: Lactobacillus spp
Airway Management• Mechanical ventilation– Avoidance of Endotracheal intubation • Mask ventilation trials , NIPPV
• Minimize duration on MV– Orotracheal intubation • Nasotracheal intubation slightly increase the risk for VAP• Avoid Reintubations- increases risk of VAP 6 fold
(Am resp.criti car med.1995;152(1):137-141)
– Cuff management HVLP ETT cuff VAP rate 20% , LVHP ETT cuff VAP rate 20%
(Text book of criti. Care. 5 th Edit. Mitchell P.Fink SHOEMAKER) Maintain at 25-30 cm H2O
Airway Management• Suctioning– In-line suctioning using closed technique than open
technique– Normal saline• Should not be routinely used to suction pts• Causes desaturation• Does not increase removal of secretions• Can potentially dislodge bacteria from ETT to LRT• Should be used to rinse the suction catheter after suctioning• Maintaining adequate hydration, proper humidification of
ventilatory circuit, nebulizer, mucolytic agent can help to decrease the viscosity and eliminate the need for saline lavage
(Am. jour.crical care nurse 2007 vol. 27; 32-36:)
Suctioning
• Oral suction devices– Policies for use and storage not written– Harbor potentially pathogenic bacteria within 24 hours– 71% of nurses store the device in its packaging (STAMP)– Best practice???
• Change suction catheter every day• Rinse with sterile water or NS• Allow to air dry
Subglottal suctioning
Should be done using a 14 Fr sterile suction catheter:– Prior to ETT rotation– Prior to lying patient supine– Prior to Extubation
Continuous subglottic suctioning ETT with dedicated lumen to continuously or intermittently
suction above the cuff may reduce the risk of VAP.
Am J Respire cri car Med Oct.. 2010
Should be used for patients expected to require >48 or 72 hours of mechanical ventilation.
Cost more than standard endotracheal tubes and are not widely available
Subglottic drainage
Device for Continuous aspiration of subglottic secreations
Ventilator Circuit-Management
Vent circuit should not be routinely opened once ventilation is initiated
Disconnection of ventilation tubing can lead to loss of PEEP and alveolar de-recruitment
If circuit must be disconnected, clamp ETT with padded Kelly forceps to avoid PEEP loss
Expiratory condensation should be removed via the trap in the tubing
Inspiratory condensation – if clean, may be drained back into the water reservoir
Ventilator circuit can be changed weekly, unless it is soiled with blood or vomitus
Ventilator Circuit-Management
Ventilator Circuits Humidification Systems
Appropriate Humidification of inspired air
Active Humidification or Passive Humidification
Heat and Humidity Exchangers (HMEs) should not be routinely changed unless:– Visibly soiled– > 5 cm H2O auto-PEEP
Ventilator Circuits Humidification Systems
• Convert to Heated Humidification (HH) if:– Ventilated longer than 96 hours– Thick/bloody secretions– Resp. Acidosis– Air leak from chest tube or
around airway– VT < 300 cc or > 750 cc
Ventilator Circuits Humidification Systems
Silver-coated endotracheal tube
Silver-coated ETTs reduce the incidence of VAP but not of other important outcomes.
(NASCENT) trial.
Enteral Feedings
Early enternal feeding decrease bacterial colonization and rate of VAP
Bolus feeding should be avoided to minimize the risk of aspiration
Elevate HOB 30 - 45 degrees Routinely verify tube placement No CDC recommendations for:– Preferential use of small bore tubes– Continuous versus intermittent feeding– Post pyloric placement CDC (2003)
Patient turning
Routine turning of patient for every 2 hrs increase pulmonary drainage and decrease the risk of VAP.Use of beds with continues lateral rotation can decrease the incidence of pneumonia but do not decreases mortality or duration of MV
(critical care 2002;30(9):1983-1986)
Recent advances
National healthcare safety(NHSN) and CDC proposed- VAP terminology changed to VAC (ventilated associated conditions and complications) not necessarily limited VAP. VAP Surveillance definination algorithm. Chest x ray is not included , and diagnosis is mainly depend on worsening of gas exchange, clinical features, isolation of microorganism in resp.secreation.
ETT- with continuous subglottic suction, ployurethrene cuff, Sponge cuff , Silver nitrate and antibiotic coated ETTs.
VAP industrial complex- kinetic beds, inlines suction catheters
VAP bunddle with 7 components – 5+ Replacing NGT to orogastric tube and Hand washing by health care personnel.
IMPLEMENTATION and ENFORCEMENT of VAP bundle
Recent advances