Trauma-associated pneumonia in adult ventilated patients

Antibiotics De-Escalation in the Treatment of Ventilator-Associated Pneumonia in Trauma Patients: A Retrospective Study on Propensity Score Matching Method

Background:

Antimicrobial de-escalation refers to starting the antimicrobial treatment with broad-spectrum antibiotics, followed by narrowing the drug spectrum according to culture results. The present study evaluated the effect of de-escalation on ventilator-associated pneumonia (VAP) in trauma patients.

Methods:

This retrospective study was conducted on trauma patients with VAP, who received de-escalation therapy (de-escalation group) or non-de-escalation therapy (non-de-escalation group). Propensity score matching method was used to balance the baseline characteristics between both groups. The 28-day mortality, length of hospitalization and Intensive Care Unit stay, and expense of antibiotics and hospitalization between both groups were compared. Multivariable analysis explored the factors that influenced the 28-day mortality and implementation of de-escalation.

Results:

Among the 156 patients, 62 patients received de-escalation therapy and 94 patients received non-de-escalation therapy. No significant difference was observed in 28-day mortality between both groups (28.6% vs. 23.8%, P = 0.620). The duration of antibiotics treatment in the de-escalation group was shorter than that in the non-de-escalation group (11 [8–13] vs. 14 [8–19] days, P = 0.045). The expenses of antibiotics and hospitalization in de-escalation group were significantly lower than that in the non-de-escalation group (6430 ± 2730 vs. 7618 ± 2568 RMB Yuan, P = 0.043 and 19,173 ± 16,861 vs. 24,184 ± 12,039 RMB Yuan, P = 0.024, respectively). Multivariate analysis showed that high Acute Physiology and Chronic Health Evaluation II (APACHE II) score, high injury severity score, multi-drug resistant (MDR) infection, and inappropriate initial antibiotics were associated with patients' 28-day mortality, while high APACHE II score, MDR infection and inappropriate initial antibiotics were independent factors that prevented the implementation of de-escalation.

Conclusions:

De-escalation strategy in the treatment of trauma patients with VAP could reduce the duration of antibiotics treatments and expense of hospitalization, without increasing the 28-day mortality and MDR infection.

Inadequacy of Algorithmic Ventilator-Associated Pneumonia Diagnosis in Acute Care Surgery

Clinical utility of algorithms to diagnose ventilator-associated pneumonia (VAP) in surgical patients has not been established. We aimed to test the diagnostic accuracy of two established methods to reliably diagnose VAP in acutely ill and injured surgical patients. After institutional review board approval, we prospectively collected data on 508 mechanically ventilated acute care surgery patients. Microbiologic samples were taken daily from all patients. Demographics, clinical, laboratory, and radiographic data were collected. The Johanson Criteria (JC) and Clinical Pulmonary Infection Score (CPIS) were calculated and analyzed. Sensitivity, specificity, and positive predictive values (PPV) and negative predictive value (NPV) were calculated in comparison to positive respiratory cultures. Of the 508 patients, 312 (61.4%) were acutely injured; emergent general surgery was performed in 141 (27.8%) patients, and 54 (10.6%) underwent elective operation. Positive respiratory cultures were identified in 198 (39%) of the 508 patients. JC diagnosed VAP in 291 (57.3%) patients (sensitivity 82.8%, specificity 59%, PPV 56.4%, NPV 84.3%, accuracy 68.3%). The CPIS resulted in 189 (37.2%) VAP diagnoses (sensitivity 61.1%, specificity 78.1%, PPV 64%, NPV 75.9%, and accuracy 71.5%). To address the inaccuracy of the algorithms, concordance testing was performed on the data to evaluate correlation between the algorithmic VAP diagnosis criteria and respiratory culture data. Nonconcordance with culture data diagnosis was identified with both JC (rho 0.41) and CPIS (rho 0.41). Sensitivity, specificity, PPV and NPV, and accuracy of both established clinical formulas was unacceptably low in acute care surgery patients.

Healthcare-associated pneumonia among U.S. combat casualties, 2009 to 2010

Although there is literature evaluating infectious complications associated with combat-related injuries from Iraq and Afghanistan, none have evaluated pneumonia specifically. Therefore, we assessed a series of pneumonia cases among wounded military personnel admitted to Landstuhl Regional Medical Center, and then evacuated further to participating U.S. military hospitals. Of the 423 casualties evacuated to the United States, 36 developed pneumonia (8.5%) and 30 of these (83.3%) were ventilator-associated. Restricting to 162 subjects admitted to intensive care, 30 patients had pneumonia (18.5%). The median Injury Severity Score was higher among subjects with pneumonia (23.0 vs. 6.0; p < 0.01). There were 61 first-isolate respiratory specimens recovered from 31 pneumonia subjects, of which 56.1% were gram-negative, 18.2% were gram-positive, and 18.2% were fungal. Staphylococcus aureus and Pseudomonas aeruginosa were most commonly recovered (10.6%, and 9.1%, respectively). Thirteen bacterial isolates (26.5%) were multidrug-resistant. Outcome data were available for 32 patients, of which 26 resolved their infection without progression, 5 resolved after initial progression, and 1 died. Overall, combat-injured casualties suffer a relatively high rate of pneumonia, particularly those requiring mechanical ventilation. Although gram-negative pathogens were common, S. aureus was most frequently isolated. Continued focus on pneumonia prevention strategies is necessary for improving combat care.

Ventilator-associated pneumonia in critically ill patients with intensive antibiotic usage

Objective:

Ventilator-associated pneumonia (VAP) is an infection with high mortality and morbidity that prolongs the length of stay in the intensive care unit (ICU) and hospitalisation. VAP is one of the most common infections in critically ill patients. This study aimed to prospectively determine the VAP rate and associated factors in critically ill patients with intensive antibiotic usage during a one-year period.

Methods:

In total, 125 out of 360 patients admitted to the intensive care unit during the one-year study period (September 2010-2011) were included for follow-up for VAP diagnosis. Demographic data, APACHE II scores, diagnoses on admission, clinical pulmonary infection scores (CPIS), CRP, procalcitonin, risk factors for infection, time to VAP diagnosis, and bacteriological culture results were recorded. All data were assessed in terms of ICU, hospital and 28-day mortality.

Results:

In total, 56 (45%) out of 125 patients were diagnosed with VAP. In addition, 91% of patients diagnosed with VAP were administered antibiotics before diagnosis. In the VAP patients, the mortality rates were 48, 68 and 71% for 28-day, ICU and hospital mortality, respectively.

Conclusion:

The coexistence of clinical and microbiological parameters should not be sought when diagnosing VAP in patients who use antibiotics intensively. VAP can be diagnosed when CPIS≤6 in cases with sufficient microbiological evidence. This strategy may decrease mortality by preventing a delay in therapy.

Ventilator-Associated Pneumonia in Pediatric Traumatic Brain Injury

Ventilator-associated pneumonia (VAP) is a common occurrence among intubated pediatric traumatic brain injury (TBI) patients. However, little is known about the epidemiology, risk factors, and microbiology of VAP in pediatric TBI. We reviewed a cohort of 119 pediatric moderate-to-severe TBI patients and identified 42 with VAP by positive protected bronchial brush specimens. Location of intubation, severity of injury, and antibiotic administration within 2 days after injury were not associated with VAP. Most treatments for elevated intracranial pressure were associated with increased risk of VAP; however, in a multi-variable analysis barbiturate coma (hazard ratio [HR], 3.2; 95% confidence interval [CI] 1.4-7.3), neuromuscular blockade (NMBA; HR, 3.4; 95% CI 1.6-7.3), and use of a cooling blanket for euthermia (HR 2.4; 95% CI 1.1-5.5) remained independently associated with VAP. Most VAP (55%) occurred prior to hospital Day 4 and only 7% developed VAP after Day 7. Methicillin-sensitive Staphylococcus aureus (34%), Haemophilus influenzae (22%), and Streptococcus pneumoniae (15%) were the most common organisms, comprising 71% of isolated pathogens (36% of infections were polymicrobial). Patients with VAP had significantly longer intensive care unit and hospital stays, as well as increased risk of chronic care needs after discharge, but not mortality. VAP is a common occurrence in pediatric TBI patients, and early empiric therapy for patients requiring barbiturate infusion, NMBA, or use of a cooling blanket could mitigate morbidity.