The value of pretest probability and modified clinical pulmonary infection score to diagnose ventilator-associated pneumonia

Association Between Daily Toothbrushing and Hospital-Acquired Pneumonia: A Systematic Review and Meta-Analysis

Importance

Hospital-acquired pneumonia (HAP) is the most common and morbid health care-associated infection, but limited data on effective prevention strategies are available.

Objective

To determine whether daily toothbrushing is associated with lower rates of HAP and other patient-relevant outcomes.

Data Sources

A search of PubMed, Embase, Cumulative Index to Nursing and Allied Health, Cochrane Central Register of Controlled Trials, Web of Science, Scopus, and 3 trial registries was performed from inception through March 9, 2023.

Study Selection

Randomized clinical trials of hospitalized adults comparing daily oral care with toothbrushing vs regimens without toothbrushing.

Data Extraction and Synthesis

Data extraction and risk of bias assessments were performed in duplicate. Meta-analysis was performed using random-effects models.

Main Outcomes and Measures

The primary outcome of this systematic review and meta-analysis was HAP. Secondary outcomes included hospital and intensive care unit (ICU) mortality, duration of mechanical ventilation, ICU and hospital lengths of stay, and use of antibiotics. Subgroups included patients who received invasive mechanical ventilation vs those who did not, toothbrushing twice daily vs more frequently, toothbrushing provided by dental professionals vs general nursing staff, electric vs manual toothbrushing, and studies at low vs high risk of bias.

Results

A total of 15 trials met inclusion criteria, including 10 742 patients (2033 in the ICU and 8709 in non-ICU departments; effective population size was 2786 after shrinking the population to account for 1 cluster randomized trial in non-ICU patients). Toothbrushing was associated with significantly lower risk for HAP (risk ratio [RR], 0.67 [95% CI, 0.56-0.81]) and ICU mortality (RR, 0.81 [95% CI, 0.69-0.95]). Reduction in pneumonia incidence was significant for patients receiving invasive mechanical ventilation (RR, 0.68 [95% CI, 0.57-0.82) but not for patients who were not receiving invasive mechanical ventilation (RR, 0.32 [95% CI, 0.05-2.02]). Toothbrushing for patients in the ICU was associated with fewer days of mechanical ventilation (mean difference, -1.24 [95% CI, -2.42 to -0.06] days) and a shorter ICU length of stay (mean difference, -1.78 [95% CI, -2.85 to -0.70] days). Brushing twice a day vs more frequent intervals was associated with similar effect estimates. Results were consistent in a sensitivity analysis restricted to 7 studies at low risk of bias (1367 patients). Non-ICU hospital length of stay and use of antibiotics were not associated with toothbrushing.

Conclusions

The findings of this systematic review and meta-analysis suggest that daily toothbrushing may be associated with significantly lower rates of HAP, particularly in patients receiving mechanical ventilation, lower rates of ICU mortality, shorter duration of mechanical ventilation, and shorter ICU length of stay. Policies and programs encouraging more widespread and consistent toothbrushing are warranted.

Quantitative correlation of colony forming units of Acinetobacter baumannii obtained from endotracheal tube aspirate culture with clinical pulmonary infection score

Background and Aims:

Ventilator-associated pneumonia (VAP) is the most common healthcare-associated infection in adult critical care units. The reason behind the different levels of severity and the outcome in different individuals is not established yet.Co-morbidities and age may be a valid reason.In an attempt to find out the reason behind the different levels of severity of VAP in different individuals, we conducted a studywith the primary objective being to assess the quantitative correlation between the colony forming units (CFU) of Acinetobacter baumannii in the endotracheal tube aspirate and the Clinical Pulmonary Infection Score (CPIS) in mechanically ventilated patients without co-morbidities. The secondary objective was to see whether the severity of VAP depends on the number of CFU(>10⁵/ml).

Methods:

This observational study was conducted in a 27-bedded intensive care unit of a tertiary care hospital in northern India. Endotracheal tube aspirate was collected from patients with suspected VAP.A total of 81 patients without any prior co-morbidity and having Acinetobacter baumannii in their endotracheal tube aspirate were included in the study group. Quantification of Acinetobacter baumannii was done by counting CFU.The CPIS was calculated for all Acinetobacter baumannii positive patients. Correlation between CFU of Acinetobacter baumannii and CPIS was assessed using Spearman's Rho correlation coefficient.

Results:

Among 81 patients having Acinetobacter baumannii infection, only 61.9% had a CPIS >4. There was an insignificant correlation between the quantity of CFUs of Acinetobacter baumannii and CPIS (P value = 0.784).

Conclusion:

Number of CFU >10⁵/ml in an endotracheal tube aspirate culture bears no relation to the severity of VAP as predicted by the CPIS.

CPIS Lung Ultrasound and the Erratic March toward Diagnostic Certainty in VAP

How to cite this article: Rajagopalan RE. CPIS Lung Ultrasound and the Erratic March toward Diagnostic Certainty in VAP. Indian J Crit Care Med 2021;25(3):255-257.

The Effects of Oral Care Protocol on the Incidence of Ventilation-Associated Pneumonia in Selected Intensive Care Units in Jordan

PURPOSE

This study aims to evaluate the effects of oral care protocol on the incidence of ventilator-associated pneumonia (VAP) at selected intensive care units (ICUs) in Jordan using clinical pulmonary infection score.

METHODS

A quasi-experimental design was used, and 1 large teaching hospital from the Jordanian capital, along with 2 hospitals from the southern region, was selected. A total of 218 patients participated, among which VAP risk in 2 independent groups was evaluated through the Clinical Pulmonary Infection Score sheet.

RESULTS

The VAP incidence rate was significantly lower in the intervention group (n = 102) as compared with control group (n = 116) (21.6 vs 35.3, respectively; P = .018); in addition, ICU stay and intubation period were significantly shorter among the intervention group. A higher risk of VAP was independently predicted by previous lung diseases (odds ratio [OR], 1.441; 95% confidence interval [CI], 1.185-1.88), open suctioning system (OR, 2.536; 95% CI, 1.261-5.101), and duration of intubation (OR, 1.770; 95% CI, 0.845-2.220). The oral care protocol has effectively improved ventilated patients' oral health, which has statistically reduced the incidence of VAP. It occurred more frequently among patients who have lung disease and those who were intubated for more than 7 days and have an open suctioning system.

CONCLUSION

Health care teams should ensure that effective care protocol is implemented among patients.

Diagnostic efficacy of serum procalcitonin, C-reactive protein concentration and clinical pulmonary infection score in Ventilator-Associated Pneumonia

OBJECTIVE

The aim of this study was to evaluate the diagnostic efficacy of serum procalcitonin (PCT), c-reactive protein (CRP) concentration and clinical pulmonary infection score(CPIS) in ventilator-associated pneumonia(VAP).

METHODS

Forty-nine patients who were admitted to the intensive care unit (ICU) of Zhejiang Hospital with suspected VAP were recruited in this study. The serum level of PCT and CRP of all patients were measured and CPIS was calculated at the time of VAP suspected diagnosis. Of the included 49 patients, 24 were finally confirmed of VAP by microbiology assay. And the other 25 patients were considered as clinical suspected VAP without microbiology confirmation. The diagnostic sensitivity, specificity and area under the receiver operating characteristic (ROC) curve (AUC) were calculated using the serum PCT, CRP concentration and CPIS. The correlation among serum PCT, CRP concentration and CPIS were also evaluated by Spearson correlation test.

RESULTS

A total of 100 bronchoscopic aspiration sputum specimen were examined in bacterial culture. 30 samples were found with suspected pathogenic bacteria. Six samples were found with 2 types of suspected pathogenic bacteria. PCT serum concentration and CPIS score were significantly different (P<0.05) between the patient group [1.4 (0.68 ∼ 2.24), 6.0 (4.25 ∼ 8.00)] and the control group [0.4 (0.17 ∼ 1.39), 3.0 (1.00 ∼ 5.00)] ; However, the serum CRP [102.8(66.75 ∼ 130.90) vs 86.1(66.95 ∼ 110.10)] was not statistically different between the two groups (P>0.05). A significant correlation was found between serum PCT and CRP concentrations (r=0.55, P<0.01), but not between PCT vs CPIS and CRP vs CPIS (p>0.05). The diagnostic sensitivity, specificity and AUC were 72.0%, 75.0%, 0.81 (0.69 ∼ 0.93) for CPIS; 60.0%, 87.5%, 0.76 (0.62 ∼ 0.90) for PCT and 68.0%, 58.3%, 0.59 (0.43 ∼ 0.76) for CRP.

CONCLUSION

PCT serum level and CPIS score are elevated in VAP patients and could therefore represent potential biomarkers for VAP early diagnosis.

Soluble triggering receptor expressed on myeloid cells-1 as a useful biomarker for diagnosing ventilator-associated pneumonia after congenital cardiac surgery in children

The present study aimed to assess the usefulness of soluble triggering receptor expressed on myeloid cells 1 (sTREM-1) in the diagnosis of ventilator-associated pneumonia (VAP) in paediatric patients with congenital heart disease (CHD) following cardiac surgery. The current prospective study enrolled 48 patients with congenital heart diseases who were suspected of having VAP; these patients were undergoing cardiac surgery between August 2016 and October 2017 in the Cardiac Intensive Care Unit of Shanghai Children's Medical Center (Shanghai, China). A total of 31 patients were diagnosed with VAP using a polymerase chain reaction (PCR) assay, while 17 patients without VAP were designated as the Non-VAP group. A bronchoscopy was performed and samples were collected for measurement on the day that VAP was diagnosed. The sTREM-1 levels were measured in bronchoalveolar lavage fluid (BALF) and exhaled ventilator condensate (EVC). BALF specimens were also sent to the microbiology laboratory for PCR assays and quantitative culturing. The positive detection rate of bacteria using the PCR assay and traditional culture was 64.6% (31/48) and 39.6% (19/48). sTREM-1 was significantly higher in the BALF (146.21 pg/ml vs. 118.06 pg/ml) and EVC (125.29 pg/ml vs. 120.48 pg/ml) of patients with VAP demonstrated compared with the patients without VAP. The findings suggest that the detection of sTREM-1 in BALF and EVC samples may be useful for the diagnosis of VAP following heart surgery in children.

Ventilator-associated pneumonia in patients assisted by veno-arterial extracorporeal membrane oxygenation support: Epidemiology and risk factors of treatment failure

INTRODUCTION

Ventilator-associated pneumonia (VAP) is frequent in Intensive Care Unit (ICU) patients. In the specific case of patients treated with Veno-Arterial Extracorporeal Membrane Oxygenation Support (VA-ECMO), VAP treatment failures (VAP-TF) have been incompletely investigated.

METHODS

To investigate the risk factors of treatment failure (VAP-TF) in a large cohort of ICU patients treated with VA-ECMO, we conducted a retrospective study in a Surgical ICU about patients assisted with VA-ECMO between January 1, 2013, and December 31, 2014. Diagnosis of VAP was confirmed by a positive quantitative culture of a respiratory sample. VAP-TF was defined as composite of death attributable to pneumonia and relapse within 28 days of the first episode.

RESULTS

In total, 152 patients underwent ECMO support for > 48h. During the VA-ECMO support, 85 (55.9%) patients developed a VAP, for a rate of 60.6 per 1000 ECMO days. The main pathogens identified were Pseudomonas aeruginosa and Enterobacteriaceae. VAP-TF occurred in 37.2% of patients and was associated with an increased 28-day mortality (Hazard Ratio 3.05 [1.66; 5.63], P<0.001), and VA-ECMO assistance duration (HR 1.47 [1.05-2.05], P = 0.025). Risk factors for VAP-TF were renal replacement therapy (HR 13.05 [1.73; 98.56], P = 0.013) and documentation of Pseudomonas aeruginosa (HR 2.36 [1.04; 5.35], P = 0.04).

CONCLUSIONS

VAP in patients treated with VA-ECMO is associated with an increased morbidity and mortality. RRT and infection by Pseudomonas aeruginosa appear as strong risks factors of treatment failure. Further studies seem necessary to precise the best antibiotic management in these patients.

Significance of Mini Bronchoalveolar Lavage Fluid Amylase Level in Ventilator-Associated Pneumonia: A Prospective Observational Study

OBJECTIVES

Aspiration of oropharyngeal or gastric contents in intubated patients can lead to ventilator-associated pneumonia. Amylase in respiratory secretion has been reported as a possible marker of aspiration. We studied whether elevated α-amylase in mini bronchoalveolar lavage specimens can be suggestive of ventilator-associated pneumonia in intubated patients with high clinical suspicion.

DESIGN

Prospective single-center observational study.

SETTING

Department of Critical Care Medicine, tertiary care academic institute.

PATIENTS

Adult patients on mechanical ventilation for more than 48 hours with with clinically suspected ventilator-associated pneumonia as per defined criteria, admitted between December 2014 and May 2016.

METHODS

Mini bronchoalveolar lavage samples were collected within 72 hours of endotracheal intubation. Samples were sent for α-amylase level assay and quantitative culture. Ventilator-associated pneumonia was confirmed from mini bronchoalveolar lavage microbial culture of greater than or equal to 10 cfu/mL, and patients were divided into ventilator-associated pneumonia and no ventilator-associated pneumonia groups. Pre- and postintubation risk factors for aspiration were also noted.

RESULTS

The prevalence of ventilator-associated pneumonia was 64.9% among 151 patients in whom it was clinically suspected. Median (interquartile range) mini bronchoalveolar lavage α-amylase levels in ventilator-associated pneumonia and no ventilator-associated pneumonia groups on the day of study inclusion were 287 U/L (164-860 U/L) and 94 U/L (59-236 U/L), respectively (p < 0.001). Median (interquartile range) α-amylase levels in patients with 0, 1, 2, and 3 preintubation risk factors were 65 U/L (35-106 U/L), 200 U/L (113-349 U/L), 867 U/L (353-1,425 U/L), and 3,453 U/L (1,865-4,304 U/L), respectively (p < 0.001) and 472 U/L (164-1,452 U/L) and 731 U/L (203-1,403 U/L) in patients with 1 and 2 postintubation risk factors, respectively (p < 0.001). A mini bronchoalveolar lavage α-amylase of 163 U/L or more yielded sensitivity and specificity of 73% and 68.6%, respectively, with area under the receiver operating characteristic curve of 0.746 (95% CI, 0.66-0.83).

CONCLUSIONS

Patients with ventilator-associated pneumonia within 72 hours from intubation have significantly elevated α-amylase concentrations in mini bronchoalveolar lavage fluid. Mini bronchoalveolar lavage α-amylase concentrations increase with increasing number of aspiration risk factors.

Accuracy and Applications of Lung Ultrasound to Diagnose Ventilator-Associated Pneumonia: A Systematic Review

BACKGROUND

Lung ultrasound (LUS) is an accurate tool to diagnose community-acquired pneumonia. However, it is not yet an established tool to diagnose ventilator-associated pneumonia (VAP).

PURPOSE

To assess the evidence about LUS in the diagnosis of VAP, we conducted a systematic review of the literature.

METHODS

We searched PubMed, Embase, Scopus, Web of Science, and LILACS. Two researchers independently selected the studies that met the inclusion criteria. Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool was used to assess the quality of the studies. In a qualitative synthesis, 3 questions guided the review: Q1. What are the sonographic signs of VAP? Q2. How can LUS be combined with others tests or signs of VAP? Q3. What is the role of LUS in VAP screening?

MAIN RESULTS

Three studies (n = 377 patients) with different designs were included. In terms of Q1, the 3 studies assessed the accuracy of sonographic consolidations. In patients suspected for VAP, lobar or hemilobar consolidation alone was not sufficient to diagnose VAP but seems useful to exclude it. The most useful signs were small subpleural consolidations (sensitivity: 81%; specificity: 41%) and dynamic air bronchograms (sensitivity: 44%; specificity: 81%). Two studies were assessed for Q2, when the 2 signs above were included in a clinical score (Ventilator-associated Pneumonia Lung Ultrasound Score associated with quantitative culture of endotracheal aspirate-VPLUS-EAquant), the accuracy was amplified (sensitivity: 48% and specificity: 97% for score ≥4; sensitivity: 78% and specificity: 77% for score ≥3 points). Finally, regarding Q3, no studies have assessed the use of LUS in screening of VAP.

CONCLUSION

Small subpleural consolidations and dynamic air bronchograms were the most useful sonographic signs to diagnose VAP in suspected patients. Clinical scores including LUS had better diagnosis accuracy than LUS alone. There are no data on LUS for VAP screening.

The Effect of a Designed Respiratory Care Program on the Incidence of Ventilator-Associated Pneumonia: A Clinical Trial

INTRODUCTION

Ventilator-associated pneumonia is a common complication of mechanical ventilation. This study aimed to evaluate the effect of designed respiratory care program on incidence of ventilator-associated pneumonia (VAP) in the mechanically ventilated patient.

METHODS

In this clinical trial, 64 patients were selected among those who had undergone mechanical ventilation in the ICU of Al‑Zahra Hospital, Isfahan, Iran, using convenience sampling method. The subjects were randomly allocated to intervention and control groups. In the intervention group an upper respiratory care program and in the control group, routine cares were done. Modified Clinical Pulmonary Infection Questionnaire was completed before and on the third, fourth and fifth day of study. Data were analyzed by Chi-square and independent t-test through SPSS Ver.13.

RESULTS

The results of this study showed that until the third day of study, the incidence of VAP was similar in the both groups. However, on the fifth day of study, the incidence of VAP in the intervention group was significantly lower than control group.

CONCLUSION

The results of this study showed that an upper respiratory care program reduced the incidence of VAP. Therefore, nurses are recommended to perform this program for prevention of VAP.

Witnessed aspiration in trauma: Frequent occurrence, rare morbidity--A prospective analysis

BACKGROUND

Aspiration events (AEs) are a well-recognized complication in trauma patients and have traditionally been considered a risk factor for pneumonia. Despite this, there is no consensus on the incidence or clinical significance of AE in the trauma population.

METHODS

All patients admitted as trauma team activations at our Level I trauma center who were intubated in the field or on arrival from September 2013 to August 2014 were prospectively collected. Field and admission data including witnessed AEs were analyzed. Additional hospital data included imaging, associated injuries, laboratory, and clinical data. Early respiratory failure, pneumonia, and hospital mortality were collected.

RESULTS

During the study period, 228 patients met inclusion criteria. Median age was 35.5 years, and Injury Severity Score (ISS) was 21.0. Overall, 58 patients (25.4%) had witnessed AEs. Patients with AE had significantly higher ISS (26.0 vs. 17.0, p = 0.027) and lower Glasgow Coma Scale (GCS) score on admission (median, 4.0 vs. 7.0; p = 0.003), despite similar field GCS score (p = 0.946). Body mass index (median, 27.2 vs. 26.2; p = 0.374) and intoxication rates (86.2% vs. 83.5%, p = 0.835) were similar between groups. Early pneumonia and respiratory failure were rare in all patients and were not higher in those with AE. Although mortality was higher after AE in patients who died directly after admission (51.7% vs. 30.0%, p = 0.004), in patients who survived to intensive care unit admission, there was no longer a difference between groups and aspiration was not an independent predictor of mortality (p = 0.107) on multivariable regression analysis.

CONCLUSION

The rate of aspiration in trauma is high and more likely to occur in patients with increased injury burden or depressed GCS score. In patients who survive past admission, early pneumonia rates are similar, regardless of AE. These data suggest that aspiration is a marker of severe illness and is associated with but not an independent predictor of mortality.

LEVEL OF EVIDENCE

Prognostic/epidemiologic study, level III.

The effect of daily sedation interruption protocol on early incidence of ventilator-associated pneumonia among patients hospitalized in critical care units receiving mechanical ventilation

Background:

Ventilator-associated pneumonia (VAP) is a common side effect in patients who receive intravenous sedation infusion. In routine care, after starting sedation infusion for patients who receive mechanical ventilation, interruption of sedation starts without protocol. This study aimed to evaluate the effect of daily sedation vacation protocol on the incidence of VAP in mechanically ventilated patients.

Materials and Methods:

In this clinical trial study, 80 patients with intravenous sedation infusion were selected and randomly allocated to intervention and control groups. In the intervention group, daily sedation vacation protocol and in the control group, routine sedation vacation was followed. Modified clinical pulmonary infection score questionnaire was completed before intervention and on the third, fourth, and fifth days after intervention. Data were analyzed by using repeated measures analysis of variance (ANOVA), Chi-square, and independent t-test.

Results:

The results of this study showed that the incidence rate of VAP in the intervention and control groups was 0% versus 15% on the third day of intervention, 12.5% versus 50% on the fourth day, and 27.5% versus 55.3% on the fifth day of intervention in the intervention and control groups, respectively. The incidence of VAP in the intervention group was significantly lower than in the control group (P < 0.05).

Conclusions:

The results of this study showed that in patients with intravenous sedation, infusion of a daily sedation vacation protocol may reduce the incidence of VAP. Therefore, in order to prevent VAP, nurses are recommended to use this daily sedation vacation protocol.

A pilot study of the noninvasive assessment of the lung microbiota as a potential tool for the early diagnosis of ventilator-associated pneumonia

BACKGROUND

Ventilator-associated pneumonia (VAP) remains a common complication in critically ill surgical patients, and its diagnosis remains problematic. Exhaled breath contains aerosolized droplets that reflect the lung microbiota. We hypothesized that exhaled breath condensate fluid (EBCF) in hygroscopic condenser humidifier/heat and moisture exchanger (HCH/HME) filters would contain bacterial DNA that qualitatively and quantitatively correlate with pathogens isolated from quantitative BAL samples obtained for clinical suspicion of pneumonia.

METHODS

Forty-eight adult patients who were mechanically ventilated and undergoing quantitative BAL (n = 51) for suspected pneumonia in the surgical ICU were enrolled. Per protocol, patients fulfilling VAP clinical criteria undergo quantitative BAL bacterial culture. Immediately prior to BAL, time-matched HCH/HME filters were collected for study of EBCF by real-time polymerase chain reaction. Additionally, convenience samples of serially collected filters in patients with BAL-diagnosed VAP were analyzed.

RESULTS

Forty-nine of 51 time-matched EBCF/BAL fluid samples were fully concordant (concordance > 95% by κ statistic) relative to identified pathogens and strongly correlated with clinical cultures. Regression analysis of quantitative bacterial DNA in paired samples revealed a statistically significant positive correlation (r = 0.85). In a convenience sample, qualitative and quantitative polymerase chain reaction analysis of serial HCH/HME samples for bacterial DNA demonstrated an increase in load that preceded the suspicion of pneumonia.

CONCLUSIONS

Bacterial DNA within EBCF demonstrates a high correlation with BAL fluid and clinical cultures. Bacterial DNA within EBCF increases prior to the suspicion of pneumonia. Further study of this novel approach may allow development of a noninvasive tool for the early diagnosis of VAP.

Diagnosis of ventilator-associated pneumonia: a pilot, exploratory analysis of a new score based on procalcitonin and chest echography

BACKGROUND

To facilitate the clinical diagnosis of ventilator-associated pneumonia (VAP) in the ICU, the Clinical Pulmonary Infection Score (CPIS) has been proposed but has shown a low diagnostic performance in subsequent studies. We propose a new score based on procalcitonin level and chest echography with the aim of improving VAP diagnosis: the Chest Echography and Procalcitonin Pulmonary Infection Score (CEPPIS).

METHODS

This retrospective pilot study recruited patients admitted to the Intensive Care Unit of the Emergency Department, Careggi University Hospital (Florence, Italy), from January 2009 to December 2011. Patients were retrospectively divided into a microbiologically confirmed VAP group or a control group based on diagnosis of VAP and positive tracheal aspirate culture.

RESULTS

A total of 221 patients were included, with 113 in the microbiologically confirmed VAP group and 108 in the control group. A CEPPIS > 5 retrospectively fixed was significantly better in predicting VAP (OR, 23.78; sensitivity, 80.5%; specificity, 85.2%) than a CPIS > 6 (OR, 3.309; sensitivity, 39.8%; specificity, 83.3%). The receiver operating characteristic area under the curve analysis also showed a significantly higher diagnostic value for CEPPIS > 5 than CPIS > 6 (0.829 vs 0.616, respectively; P < .0001).

CONCLUSIONS

In this pilot, exploratory analysis, CEPPIS is effective in predicting VAP. Prospective validation is needed to confirm the potential value of this score to facilitate VAP diagnosis.

Derivation of urine output thresholds that identify a very high risk of AKI in patients with septic shock

BACKGROUND AND OBJECTIVES

To promote early detection of AKI, recently proposed pretest probability models combine sub-Kidney Disease Improving Global Outcomes (KDIGO) AKI criteria with baseline AKI risk. The primary objective of this study was to determine sub-KDIGO thresholds that identify patients with septic shock at highest risk for AKI.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This was a retrospective analysis of 390 adult patients admitted to the medical intensive care unit (ICU) of a tertiary, academic medical center with septic shock between January 2008 and December 2010. Hourly urine output was collected from the time of septic shock recognition (hour 0) to hour 96, urine catheter removal, or ICU discharge (whichever occurred first). All available serum creatinine (SCr) measurements were collected until hour 96. The AKI pretest probability model was assessed during the first 12 hours of resuscitation and included the initial episode of oliguria, increase from baseline to peak SCr level, and Acute Physiology and Chronic Health Evaluation (APACHE) III score in a multivariable receiver-operator characteristic (ROC) analysis. The primary outcome was the incidence of stage II or III (stage II+) AKI defined by KDIGO criteria. Secondary outcomes included the need for RRT and 28-day mortality.

RESULTS

Ninety-eight (25%) patients developed stage II+ AKI after septic shock recognition. APACHE III score and increase in SCr level in the first 12 hours were not statistically associated with stage II+ AKI in multivariable ROC analysis. Consecutive oliguria for 3 hours had fair predictive ability for achieving stage II+ AKI criteria (area under ROC curve, 0.73; 95% confidence interval [95% CI], 0.68 to 0.78), and oliguria for 5 hours demonstrated optimal accuracy (82%; 95% CI, 79% to 86%).

CONCLUSIONS

Three to 5 hours of consecutive oliguria in patients with septic shock may provide a valuable measure of AKI risk. Further validation to support this finding is needed.

JURaSSiC: accuracy of clinician vs risk score prediction of ischemic stroke outcomes

OBJECTIVE

We compared the accuracy of clinicians and a risk score (iScore) to predict observed outcomes following an acute ischemic stroke.

METHODS

The JURaSSiC (Clinician JUdgment vs Risk Score to predict Stroke outComes) study assigned 111 clinicians with expertise in acute stroke care to predict the probability of outcomes of 5 ischemic stroke case scenarios. Cases (n = 1,415) were selected as being representative of the 10 most common clinical presentations from a pool of more than 12,000 stroke patients admitted to 12 stroke centers. The primary outcome was prediction of death or disability (modified Rankin Scale [mRS] ≥3) at discharge within the 95% confidence interval (CI) of observed outcomes. Secondary outcomes included 30-day mortality and death or institutionalization at discharge.

RESULTS

Clinicians made 1,661 predictions with overall accuracy of 16.9% for death or disability at discharge, 46.9% for 30-day mortality, and 33.1% for death or institutionalization at discharge. In contrast, 90% of the iScore-based estimates were within the 95% CI of observed outcomes. Nearly half (n = 53 of 111; 48%) of participants were unable to accurately predict the probability of the primary outcome in any of the 5 rated cases. Less than 1% (n = 1) provided accurate predictions in 4 of the 5 cases and none accurately predicted all 5 case outcomes. In multivariable analyses, the presence of patient characteristics associated with poor outcomes (mRS ≥3 or death) in previous studies (older age, high NIH Stroke Scale score, and nonlacunar subtype) were associated with more accurate clinician predictions of death at 30 days (odds ratio [OR] 2.40, 95% CI 1.57-3.67) and with a trend for more accurate predictions of death or disability at discharge (OR 1.85, 95% CI 0.99-3.46).

CONCLUSIONS

Clinicians with expertise in stroke performed poorly compared to a validated tool in predicting the outcomes of patients with an acute ischemic stroke. Use of the risk stroke outcome tool may be superior for decision-making following an acute ischemic stroke.

Ventilator-associated pneumonia in severe traumatic brain injury: the clinical significance of admission chest computed tomography findings

BACKGROUND

Ventilator-associated pneumonia (VAP) in severe traumatic brain injury (STBI) is a significant morbidity. Bilateral dependent consolidation (BDC) can be seen on admission chest computed tomography (CCT) in STBI. We hypothesize that this finding may be associated with VAP.

MATERIALS AND METHODS

We retrospectively studied patients who sustained STBI after blunt injury and survived >48 h, who were admitted over a 40-mo period. We defined STBI as an admission Glasgow Coma Scale Score ≤ 8. We identified VAP by an elevated white blood cell count, a new infiltrate on chest x-ray, and a positive respiratory culture in a ventilated patient. Variables included demographics, injury, admission CCT, and culture data. We compared BDC-positive and BDC-negative patients.

RESULTS

There were 33 cases of VAP in 94 study patients (35.1%), in whom the incidence of intracranial pressure (ICP) monitoring (66.7% versus 39.3%; P = 0.011) was significantly increased. Ventilator-associated pneumonia was significantly increased in the 28 patients (29.8%) in the BDC-positive group (16 [57.1%] versus 17 (25.6%); P = 0.004). Bilateral dependent consolidation independently predicted VAP. In the 33 VAP cases, gram-negative organisms were present in 27 patients (81.8%), with a predominance of Enterobacteriaceae (16 patients [48.5%]). Culture results did not significantly differ between the early (<4 d) versus late or BDC-positive versus BDC-negative VAP groups.

CONCLUSIONS

Ventilator-associated pneumonia is common after STBI, and BDC is independently associated; however, there is no predilection for specific organisms. Admission CCT findings may prove useful in identifying a group of STBI patients at higher risk for VAP.

Pulmonary emergencies: pneumonia, acute respiratory distress syndrome, lung abscess, and empyema

This article describes the clinical presentation of pneumonia, acute respiratory distress syndrome, lung abscess, and empyema: life-threatening infections of the pulmonary system. The etiology and risk factors for each of these conditions are described, diagnostic approaches are discussed, and evidence-based management options are reviewed.

Ventilator-associated pneumonia in burn patients: a cause or consequence of critical illness?

Infectious complications are a constant threat to thermally injured patients during hospitalizations and are a predominant cause of death. Most of the infections that develop in burn patients are nosocomial and of a pulmonary etiology. The bacteria that cause ventilator associated pneumonia (VAP) take advantage of the fact that uniquely among intensive care unit patients endotracheal intubation allows them a 'free' passage to the sterile lower airways; however, the combination of severe thermal injury (systemic immunosuppression) and inhalation injury (local immunosuppression and tissue injury) create an ideal environment for development of VAP. Thus, strategies directed at preventing and treating VAP in burn patients must address not only rapid extubation and VAP prevention bundles known to work in other intensive care unit populations, but therapies directed to more rapid wound healing and restoration of pulmonary patency.

Electronic nose analysis of bronchoalveolar lavage fluid

BACKGROUND

Electronic nose (E-nose) technology has been successfully used to diagnose a number of microbial infections. We have investigated the potential use of an E-nose for the diagnosis of ventilator-associated pneumonia (VAP) by detecting micro-organisms in bronchoalveolar lavage (BAL) fluid in a prospective comparative study of E-nose analysis and microbiology.

MATERIALS AND METHODS

BAL samples were collected using a blind technique from 44 patients following a minimum of 72 h mechanical ventilation. Control samples were collected from six patients mechanically ventilated on the intensive care unit (ICU) immediately following elective surgery. Quantitative microbiological culture and E-nose headspace analysis of the BAL samples were undertaken. Multivariate analysis was applied to correlate E-nose response with microbiological growth.

RESULTS

E-nose fingerprints correctly classified 77% of the BAL samples, with and without microbiological growth from patients not on antibiotics. Inclusion of patients on antibiotics resulted in 68% correct classification. Seventy per cent of isolates, cultured in the laboratory from the clinical samples, were accurately discriminated into four clinically significant groups.

CONCLUSIONS

E-nose technology can accurately discriminate between different microbial species in BAL samples from ventilated patients on ICU at risk of developing VAP with accuracy comparable with accepted microbiological techniques.