Diagnostic Accuracy of Lung Ultrasound Performed by Novice Versus Advanced Sonographers for Pneumonia in Children: A Systematic Review and Meta-analysis.

BACKGROUND: Childhood pneumonia is a leading cause of mortality worldwide. Growing evidence suggests that lung ultrasound (LUS) may be a reliable diagnostic alternative to chest x-ray for childhood pneumonia. However, it is unclear whether sonographer experience affects the diagnostic accuracy of LUS. We summarize the diagnostic accuracy of LUS for pneumonia and compare the performance between novice and advanced sonographers with a systematic review and meta-analysis. METHODS: We searched PubMed and EMBASE from inception to February 2018 for eligible studies that evaluated the utility of LUS in children suspected of having pneumonia against the reference standard of either imaging results alone or a combination of clinical, laboratory, and imaging results. We reported the study using the Preferred Reporting Items for a Systematic Review and Meta-analysis of Diagnostic Test Accuracy Studies. We used QUADAS-2 to appraise the included studies' methodologic quality. We employed a random-effect bivariate model and a hierarchical summary receiver operating characteristic curve to evaluate LUS's performance characteristics. We conducted subgroup analyses and meta-regression based on level of sonographer training to summarize and compare LUS's diagnostic accuracy for pneumonia between novice (training ≤ 7 days) and advanced sonographers. RESULTS: Twenty-five studies (n = 3,353) were included in the meta-analysis. For diagnosing pneumonia, LUS demonstrated an overall sensitivity of 0.94 (95% confidence interval [CI] = 0.89 to 0.97), specificity of 0.92 (95% CI = 0.78 to 0.98), positive likelihood ratio of 12.40 (95% CI = 4.00 to 38.10), and negative likelihood ratio of 0.07 (95% CI = 0.04 to 0.12), with an area under ROC curve of 0.97 (95% CI = 0.95 to 0.98). Meta-regression revealed a significant difference in the diagnostic accuracy for pneumonia for LUS between novice and advanced sonographers (p < 0.01). CONCLUSION: LUS can accurately diagnose pneumonia in children. However, this test demonstrates operator-dependent variability, with more experienced sonographers having higher diagnostic accuracy. Further work on evidence-based educational methods to train novice sonographers in LUS is required.

Management of Atrial Fibrillation with Rapid Ventricular Response in the Intensive Care Unit: A Secondary Analysis of Electronic Health Record Data.

PURPOSE: Atrial fibrillation with rapid ventricular response (RVR) is common during critical illness. In this study, we explore the comparative effectiveness of three commonly used drugs (metoprolol, diltiazem, and amiodarone) in the management of atrial fibrillation with RVR in the intensive care unit (ICU). METHODS: Data pertaining to the first ICU admission were extracted from the Medical Information Mart for Intensive Care III database. Patients who received one of the above pharmacologic agents while their heart rate was > 110 bpm and had atrial fibrillation documented in the clinical chart were included. Propensity score weighting using a generalized boosted model was used to compare medication failure rates (second agent prior to termination of RVR). Secondary outcomes included time to control, control within 4 h, and mortality. RESULTS: One thousand six hundred forty-six patients were included: 736 received metoprolol, 292 received diltiazem, and 618 received amiodarone. Compared with those who received metoprolol, failure rates were higher amongst those who received amiodarone (OR 1.39, 95% CI 1.03-1.87, P = 0.03) and there was a trend towards increased failure rates in patients who received diltiazem (OR 1.35, CI 0.89-2.07, P = 0.16). Amongst patients who received a single agent, patients who received diltiazem were less likely to be controlled at 4-h than those who received metoprolol (OR 0.64, CI 0.43-097, P = 0.03). Initial agent was not associated with in-hospital mortality. CONCLUSIONS: In this study, metoprolol was the most commonly used agent for atrial fibrillation with RVR. Metoprolol had a lower failure rate than amiodarone and was superior to diltiazem in achieving rate control at 4 h.

Peripheral Edema, Central Venous Pressure, and Risk of AKI in Critical Illness.

BACKGROUND AND OBJECTIVES: Although venous congestion has been linked to renal dysfunction in heart failure, its significance in a broader context has not been investigated. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Using an inception cohort of 12,778 critically ill adult patients admitted to an urban tertiary medical center between 2001 and 2008, we examined whether the presence of peripheral edema on admission physical examination was associated with an increased risk of AKI within the first 7 days of critical illness. In addition, in those with admission central venous pressure (CVP) measurements, we examined the association of CVPs with subsequent AKI. AKI was defined using the Kidney Disease Improving Global Outcomes criteria. RESULTS: Of the 18% (n=2338) of patients with peripheral edema on admission, 27% (n=631) developed AKI, compared with 16% (n=1713) of those without peripheral edema. In a model that included adjustment for comorbidities, severity of illness, and the presence of pulmonary edema, peripheral edema was associated with a 30% higher risk of AKI (95% confidence interval [95% CI], 1.15 to 1.46; P<0.001), whereas pulmonary edema was not significantly related to risk. Peripheral edema was also associated with a 13% higher adjusted risk of a higher AKI stage (95% CI, 1.07 to 1.20; P<0.001). Furthermore, levels of trace, 1+, 2+, and 3+ edema were associated with 34% (95% CI, 1.10 to 1.65), 17% (95% CI, 0.96 to 1.14), 47% (95% CI, 1.18 to 1.83), and 57% (95% CI, 1.07 to 2.31) higher adjusted risk of AKI, respectively, compared with edema-free patients. In the 4761 patients with admission CVP measurements, each 1 cm H2O higher CVP was associated with a 2% higher adjusted risk of AKI (95% CI, 1.00 to 1.03; P=0.02). CONCLUSIONS: Venous congestion, as manifested as either peripheral edema or increased CVP, is directly associated with AKI in critically ill patients. Whether treatment of venous congestion with diuretics can modify this risk will require further study.

The Association Between Indwelling Arterial Catheters and Mortality in Hemodynamically Stable Patients With Respiratory Failure: A Propensity Score Analysis.

BACKGROUND: Indwelling arterial catheters (IACs) are used extensively in the ICU for hemodynamic monitoring and for blood gas analysis. IAC use also poses potentially serious risks, including bloodstream infections and vascular complications. The purpose of this study was to assess whether IAC use was associated with mortality in patients who are mechanically ventilated and do not require vasopressor support. METHODS: This study used the Multiparameter Intelligent Monitoring in Intensive Care II database, consisting of > 24,000 patients admitted to the Beth Israel Deaconess Medical Center ICU between 2001 and 2008. Patients requiring mechanical ventilation who did not require vasopressors or have a diagnosis of sepsis were identified, and the primary outcome was 28-day mortality. A model based on patient demographics, comorbidities, vital signs, and laboratory results was developed to estimate the propensity for IAC placement. Patients were then propensity matched, and McNemar test was used to evaluate the association of IAC with 28-day mortality. RESULTS: We identified 1,776 patients who were mechanically ventilated who met inclusion criteria. There were no differences in the covariates included in the final propensity model between the IAC and non-IAC propensity-matched groups. For the matched cohort, there was no difference in 28-day mortality between the IAC group and the non-IAC group (14.7% vs 15.2%; OR, 0.96; 95% CI, 0.62-1.47). CONCLUSIONS: In hemodynamically stable patients who are mechanically ventilated, the presence of an IAC is not associated with a difference in 28-day mortality. Validation in other datasets, as well as further analyses in other subgroups, is warranted.

Proton pump inhibitor use is not associated with cardiac arrhythmia in critically ill patients.

Hypomagnesemia can lead to cardiac arrythmias. Recently, observational data have linked chronic proton pump inhibitor (PPI) exposure to hypomagnesemia. Whether PPI exposure increases the risk for arrhythmias has not been well studied. Using a large, single-center inception cohort of critically ill patients, we examined whether PPI exposure was associated with admission electrocardiogram readings of a cardiac arrhythmia in more than 8000 patients. There were 25.4% PPI users, whereas 6% were taking a histamine 2 antagonist. In all, 14.0% had a cardiac arrhythmia. PPI use was associated with an unadjusted risk of arrhythmia of 1.15 (95% CI,1.00-1.32; P =.04) and an adjusted risk of arrhythmia of 0.91 (95% CI, 0.77-1.06; P =.22). Among diuretic users (n = 2476), PPI use was similarly not associated with an increased risk of cardiac arrhythmia. In summary, in a large cohort of critically ill patients, PPI exposure is not associated with an increased risk of cardiac arrhythmia.