FAQs: Pneumonia (PNEU) Events
Ventilator-associated [VAP] and non-ventilator-associated Pneumonia [PNEU]
Q1: Can you explain the use of PNEU, LRI and VAE and when and where surveillance for each can be performed?
We need to consider events occurring in patients on mechanical ventilation and events occurring in patients NOT on mechanical ventilation, and we have to consider events that occur in adults and events that occur in neonates and in children. Let’s review what is available for in-plan or off-plan surveillance of lower respiratory tract events in NHSN. Keep in mind that “in-plan” surveillance means that you have committed to following the NHSN surveillance protocol for that particular event in your NHSN monthly reporting plan. “Off-plan” surveillance is surveillance that is done because you/your facility have decided to track a particular event for internal use. Data that are entered into NHSN “off-plan” are not used or reported on in NSHN annual reports or other NHSN publications. A facility makes no commitment to follow the protocol for “off-plan” events.
What lower respiratory tract event surveillance can be done “in-plan”?
- VAE: This is the ONLY in-plan respiratory event surveillance for patients in adult locations. The VAE algorithm is ONLY applicable to mechanically-ventilated patients housed in adult inpatient units (regardless of the age of the patient). Pediatric and neonatal units are excluded from VAE surveillance (even in circumstances where a pediatric unit may occasionally care for adult patients).
- Pediatric VAP: This is the ONLY in-plan respiratory event surveillance for patients in pediatric locations. Pediatric VAP surveillance using the PNEU event protocol continues to be available for in-plan surveillance of VAP in pediatric locations (regardless of the age of the patient). In-plan surveillance for ventilator-associated PNEU (VAP) is no longer available for patients in neonatal locations.
NOTE: When conducting CLABSI surveillance, the PNEU definition is available for use as a site specific infection to which a bloodstream infection can be assigned as a secondary BSI for all patients (i.e., adults, children, neonates, ventilated or non-ventilated).
What lower respiratory tract event surveillance can be done “off-plan”?
- VAE: VAE surveillance can also be done “off-plan” in adult patient locations.
- VAP: Surveillance for PNEU/VAP continues to be available for off-plan surveillance in all mechanically-ventilated patients (adults, children or neonates).
- PNEU: Surveillance for PNEU is available for off-plan surveillance in non-mechanically-ventilated adults, children and neonates.
- LRI: Surveillance for non-pneumonia lower respiratory infections (using LUNG definition) continues to be available for off-plan surveillance in adults, children and neonates.
Q2: Can I conduct surveillance for VAE and PNEU and LRI in the same unit?
In theory, yes in an adult location only. You may wish to consider whether this is the best use of resources. For example, it is possible for a particular unit to be conducting simultaneous in-plan VAE surveillance and off-plan PNEU and LRI surveillance. These are considered separate events; in other words, detection of one type of event (such as a VAE) in a particular patient would have no bearing on the conduct of surveillance for the other event types in the same patient. Keep in mind there are reporting requirements such that patients who met a PNEU definition as well as the LRI-LUNG definition are to be reported as PNEU. Patients who meet a VAE definition and a PNEU definition, or a VAE definition and an LRI definition, would have both events entered into NHSN in units where surveillance for multiple respiratory events is occurring.
Q3: How do I meet the imaging test requirement?
Imaging test evidence for pneumonia must be definitive. The findings must provide evidence suggestive of pneumonia. This includes but is not limited to a new or worsening infiltrate, consolidation, opacity, or air space disease that is not attributed to something other than pneumonia
Evidence of persistence. There should not be rapid resolution of the finding or contradictory information in a subsequent imaging test which suggests the finding is attributable to another condition (for example 2 days later the opacity is now attributed to pulmonary edema). Pneumonia may have rapid onset and progression, but does not resolve quickly. Rapid imaging resolution suggests that the patient does not have pneumonia, but rather a non-infectious process.
Q4: Are patients included in VAP surveillance during periods of time when they are undergoing weaning/mechanical ventilation liberation trials?
Yes. As long as the patient is receiving support from a mechanical ventilator for some portion of each calendar day he is eligible for VAP surveillance. Keep in mind, it is important to conduct your device day count at the same time every day and only include those patients on ventilator support at the time of the count. Therefore, we recommend ventilator day counts perhaps be conducted at night, so as to capture all eligible patients (to include those who are undergoing weaning) in the denominator for the location where surveillance is being conducted .
Q5: When referencing the pathogens that are excluded for meeting the PNEU definition, what does Candida species or yeast not otherwise specified; coagulase-negative Staphylococcus species and Enterococcus species refer to?
This means the following are excluded:
Candida species—those that have been identified to the species level such as Candida albicans, those that are reported as Candida species and also to include culture reports that may simply say, for example, “many yeast isolated”
All coagulase-negative Staphylococcus species—for example, coagulase negative Staphylococci, Staphylococcus epidermidis, Staphylococcus species
All Enterococcus species –for example, Enterococcus species, Enterococcus faecalis, VRE
Q6: What if a blood specimen collection date occurs outside the Infection Window Period of PNU1 or does not match the pathogen used to meet PNU2 or PNU3? Is it possible for a BSI to still be attributed to the PNEU event?
Yes, it is possible.
A secondary BSI cannot be attributed to PNU1.However, in this instance if a BSI is thought to be secondary to pneumonia but the blood culture collection date did not occur within the infection window period such that it could be used as an element to meet the PNU2 definition, reassess to determine if the PNU2 definition can be met within the PNU1 RIT. Similarly if PNU2 is met and there is a subsequent blood specimen with an eligible pathogen, however it does not match the specimen used to originally meet PNU2, then reassess to determine if PNU2 can be met using the blood culture such that the date of event falls within the originally established PNEU-RIT. See the example and table below.
All elements necessary to satisfy the PNU1 definition occur within the infection window period. The date of event is 2/14. This establishes a PNEU (PNU1) RIT 2/14- 2/27 and a BSI secondary attribution period 2/11 – 2/27. Subsequently a blood specimen with a collection date 2/20 identifies Pseudomonas aeruginosa. The collection date is within the secondary BSI attribution period for the PNEU event however a secondary BSI cannot be reported for PNU1 since the blood culture is not used to satisfy the PNU1 definition and there is no site specific culture to which the blood culture pathogen can match. If during the PNEU RIT, all elements needed to meet the PNU2 definition are present to include the blood specimen and this results in a date of event within the RIT, then the BSI can be attributed as secondary to the PNEU event. The PNEU date of event remains as 2/14, as does the originally determined RIT, secondary BSI attribution period, device association and location of attribution. If the PNU2 definition is not met as described above and if additionally, another specific site infection for which the BSI can be attributed as a secondary BSI is not identified, then the BSI is a primary BSI/CLABSI.
Q7: Can identification of an eligible organism from sputum or endotracheal aspirate used to satisfy the PNU2 or PNU3 laboratory finding?
Please note that the respiratory tract specimens eligible for satisfying the PNU2 or PNU3 criterion specify that the specimen be a minimally contaminated lower respiratory tract specimen. This includes BAL, protected specimen brushing and endotracheal aspirate. Note endotracheal aspirate indicates the specimen is collected via an artificial airway. Sputum is not a minimally contaminated specimen and therefore not available for use in meeting PNU2 and sputum is only available for use when meeting PNU3 if a matching Candida species is identified in both sputum and blood and both specimen collection dates are found in the same infection window period.
Q8: When imaging test findings are not definitive for pneumonia what is the next step?
When findings are not definitive (e.g., a report of infiltrate vs. atelectasis or a report stating opacity may be pneumonia or may represent congestive heart failure) then there must be further delineation that the finding is suggestive of pneumonia and that there is persistence. This may be accomplished by:
- Subsequent imaging test with more conclusive evidence for pneumonia
- Clinical correlation in the medical record such that the physician is indicating his/her interpretation is that the non-definitive imaging test is interpreted as evidence of pneumonia and there is evidence of treatment for pneumonia
Q9: How is the requirement for bronchial breath sounds met?
Bronchial breath sounds are generally documented as such when heard upon auscultation. Documentation in the medical record of “bronchial breath sounds heard” will satisfy this requirement. If a physician / provider documents “bronchial breath sounds” the finding is considered abnormal as he/she is indicating he/she is hearing bronchial breath sounds in a place they should not be heard. If no documentation similar to this is found in the medical record for purposes of NHSN surveillance “bronchial breath sounds” were not heard and that element of the definition is not available for use in meeting a PNEU definition.