An evaluation of clinical stability criteria to predict hospital course in community-acquired pneumonia.

A number of different methods exist to assess clinical stability, a key component of pneumonia management. We compared the prognostic value of different stability criteria through a secondary analysis of the Edinburgh pneumonia study database. We studied four clinical stability criteria (Halm's criteria, the ATS criteria, CURB and 50% or more decrease in C-reactive protein from baseline). Outcomes included 30-day mortality, need for mechanical ventilation or vasopressor support (MV/VS), development of a complicated pneumonia, and a combined outcome of the above. A total of 1079 patients (49.8% male), with a median age of 68 years (IQR 53-80), were included. Ninety-three patients (8.6%) died by day 30, 91 patients (8.4%) required MV/VS and 99 patients (9.2%) developed a complicated pneumonia. Patients with increasing severity of pneumonia on admission, assessed by both CURB-65 and PSI, took a progressively longer time to achieve clinical stability assessed by any method (p < 0.001 for all criteria). Halm's criteria had the highest area under the curve (AUC) for prediction of 30-day mortality (AUC 0.95 (0.94-0.96)), need for MV/VS (AUC 0.96 (0.95-0.97)) and combined adverse outcome (AUC 0.96 (0.95-0.97)). C-reactive protein had the highest area under the curve for complicated pneumonia (AUC 0.96 (0.95-0.97)). Adding C-reactive protein to Halm's criteria increased the area under the curve, but the difference was only statistically significant for complicated pneumonia. All of the criteria performed well in predicting adverse outcomes in patients with pneumonia. Halm's criteria performed best when identifying patients at low risk of complications.

Thrombus load and acute right ventricular failure in pulmonary embolism: correlation and demonstration of a "tipping point" on CT pulmonary angiography.

OBJECTIVES: The aim of this study was to determine the correlation between increasing pulmonary embolism thrombus load and right ventricular (RV) dilatation as demonstrated by CT pulmonary angiography (CTPA) and to assess the thrombus load threshold which indicates impending RV decompensation. METHODS: 2425 consecutive CTPAs were retrospectively analysed. Thrombus load using a modified Miller score (MMS), RV to left ventricular (RV:LV) ratio, presence of septal shift, and pulmonary artery and aorta size were analysed in 504 positive CTPA scans and a representative cohort of 100 negative scans. Results were correlated using non-parametric analysis (two-tailed t-test or χ(2) test) and Pearson's rank correlation. RESULTS: Increasing thrombus load correlated with a higher RV:LV ratio, with a statistically significant difference in RV:LV ratios between the negative and positive pulmonary embolism (PE) cohorts. Larger thrombus loads (MMS ≥12 vs MMS <12) were strongly correlated with RV strain (mean RV:LV ratio, 1.323 vs 0.930; p<0.0001). Smaller thrombus loads had no significant influence on RV strain. Septal shift was also more likely with an MMS of ≥12, as was an increase in pulmonary artery diameter (r=0.221, p<0.001). CONCLUSION: With increasing thrombus load in PE, there is CTPA evidence of RV decompensation with an MMS threshold of 12. This suggests a "tipping point" beyond which RV decompensation is more likely to occur. This is the first study to describe this tipping point between a thrombus load of MMS >12 and an increase in RV:LV ratio. This finding may help to improve risk stratification in patients with acute PE diagnosed by CTPA.

Seven-day antibiotic courses have similar efficacy to prolonged courses in severe community-acquired pneumonia--a propensity-adjusted analysis.

There are no studies to guide the optimal duration of therapy in severe community-acquired pneumonia (CAP). The aim of this study was to determine whether 7 days of antibiotic treatment is equivalent to longer-course therapy in severe CAP. In this prospective observational study, we included patients with severe CAP (CURB65 score 3-5) admitted to the hospital with signs and symptoms consistent with pneumonia. A propensity score, derived through multiple logistic regression, was used to match patients into two groups: treated for 7 days vs. treated for >7 days. Patients who died, were admitted to the intensive-care unit, developed complicated pneumonia, failed to reach clinical stability or had positive cultures for microorganisms requiring prolonged treatment within the first 7 days were excluded. Patients outside the mutual range of the propensity score were also excluded. The primary outcome of this study was 30-day mortality. Secondary outcomes were subsequent requirement for mechanical ventilation and/or inotropic support and the development of complicated pneumonia or re-admission within 30 days. Four hundred and twelve patients were suitable for derivation of the propensity score. After matching on propensity score, 164 patients treated for 7 days were compared with 164 treated for >7 days; they were well matched in terms of age, gender, comorbidities, and physiological parameters. The results showed no significant differences in the primary and the secondary outcomes between the two groups. This study therefore suggests that, in the majority of severe CAP patients who have clinically responded, antibiotics can be safely discontinued at 7 days.

Predicting mortality with severity assessment tools in out-patients with community-acquired pneumonia.

INTRODUCTION: In community-acquired pneumonia, severity assessment tools, such as CRB65, CURB65 and Pneumonia Severity Index (PSI), have been promoted to increase the proportion of patients treated in the community. The prognostic accuracy of these scores is established in hospitalized patients, but less is known about their use in out-patients. We aimed to study the accuracy of these severity tools to predict mortality in patients managed as out-patients. METHODS: We performed a systematic review and meta-analysis according to MOOSE guidelines. From 1980 to 2010, we identified 13 studies reporting prognostic information for the CRB65, CURB65 and PSI severity scores in out-patients (either exclusively managed in the community or discharged from an emergency department <24 h after admission). Two reviewers independently collected data and assessed study quality. Performance characteristics across the studies were pooled using a random-effects model. Relationships between sensitivity and specificity were plotted using summary receiver operator characteristic curves (sROC). RESULTS: Out-patient mortality ranged from 0% to 3.5%. Four studies were identified for CRB65, 2 for CURB65 and 10 for PSI. Mortality was low for out-patients in the low-risk CRB65 classes [CRB65 0 or 1: mortality occurred in 3 of 1494 patients (0.2%)] but higher in CRB65 Groups 2-4 [mortality 13 of 154 patients (8.4%)]. Similarly, mortality was low in PSI Classes I-III [mortality 8 of 3655 patients (0.2%)] managed as out-patients but higher in Classes IV and V [mortality 32 of 317 patients (10.1%)]. CRB65 showed pooled sensitivity of 81% (54-96%), pooled specificity of 91% (90-93%) and the area under the sROC was 0.91 [standard error (SE) 0.05]. For PSI, pooled sensitivity was 92% (64-100%), pooled specificity was 90% (89-91%) and area under the sROC was 0.92 (SE 0.03). There were insufficient studies to analyse CURB65. CONCLUSION: The limited data available suggest that CRB65 and PSI can identify groups of patients at low risk of mortality that can be safely managed in the community.

Impact of inhaled corticosteroid use on outcome in COPD patients admitted with pneumonia.

The aim of this study was to investigate whether inhaled corticosteroid (ICS) use affects outcome in patients with chronic obstructive pulmonary disease (COPD) admitted with community-acquired pneumonia (CAP). This was a prospective, observational study of patients with spirometry-confirmed COPD presenting with a primary diagnosis of CAP in Lothian, UK. Outcome measures were compared between ICS users and non-ICS users. Of 490 patients included in the study, 76.7% were classified as ICS users. ICS users had higher Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage compared with non-ICS users (mean ± sd 3.2 ± 0.8 versus 2.6 ± 0.9; p<0.0001). There were no significant differences in pneumonia severity (mean ± sd Pneumonia Severity Index (PSI) 4.2 ± 0.8 versus 4.3 ± 0.8 (p = 0.3); mean ± sd CURB-65 score 2.1 ± 1.3 versus 2.3 ± 1.3 (p = 0.07)) or markers of systemic inflammation (median C-reactive protein 148 (interquartile range 58-268) mg·L(-1) versus 183 (IQR 85-302) mg·L(-1); p = 0.08) between ICS users and non-ICS users. On multivariable analysis, after adjustment for COPD severity and PSI, ICS use was not independently associated with 30-day mortality (OR 1.71, 95% CI 0.75-3.90; p = 0.2), 6-month mortality (OR 1.62, 95% CI 0.82-3.16; p = 0.2), requirement for mechanical ventilation and/or inotropic support (OR 0.73, 95% CI 0.33-1.62; p = 0.4) or development of complicated pneumonia (OR 0.71, 95% CI 0.25-1.99; p = 0.5). Prior ICS use had no impact on outcome in patients with COPD admitted with CAP.

Physician judgement is a crucial adjunct to pneumonia severity scores in low-risk patients.

This study investigates the reasons for hospitalisation in patients with low-risk (CURB-65 score 0-1) community-acquired pneumonia (CAP), with a view to identifying the potential for improving outpatient management. As part of a prospective observational study of CAP, we evaluated reasons for hospitalisation in these low-risk patients. 565 patients had low-risk CAP and 420 of these were admitted (for >12 h). 39.3% had additional markers of severity justifying admission, 29.5% of the admissions were required for further management that could not be provided rapidly in the community, 11.9% had unsafe social circumstances and 19.3% had no clinical reason justifying hospitalisation. 30-day mortality was increased in patients with additional severity markers (6.7%), which was significantly higher compared with 0% for patients awaiting investigations (p=0.009) and 0% without a clear indication for hospitalisation (p=0.04). In a logistic regression analysis, parameters associated with 30-day mortality were chronic cardiac comorbidity (adjusted odds ratio (aOR) 5.73, 95% CI 1.52-21.6; p=0.01), acidosis (aOR 5.14, 95% CI 1.44-18.3; p=0.01), hypoxia (aOR 9.86, 95% CI 2.39-40.7; p=0.002) and multilobar chest radiograph shadowing (aOR 4.54, 95% CI 1.21-17.1; p=0.03). This study supports recommendations from international guidelines that pneumonia severity scores should be used as an adjunct to clinical judgement, when deciding on hospitalisation.

Vascular complications are associated with poor outcome in community-acquired pneumonia.

BACKGROUND: Recognition of cardiovascular risk factors is important for primary and secondary prevention strategies. Recent evidence has linked lower respiratory tract infections with the development of acute myocardial infarction. AIM: The aim of this study was to determine the frequency of cardiovascular and cerebrovascular events and the clinical outcomes, during hospitalization for community-acquired pneumonia (CAP). DESIGN: We performed a retrospective study of 4408 patients with CAP presenting to five hospitals over a 2-year period. Clinical information, co-morbidities, cardiovascular events and 90-day mortality were collected from review of medical case notes. The relationship between cardiovascular events and outcomes were analysed using multivariable logistic regression. RESULTS: From a total of 4408 patients, 2.2% developed stroke, 5% acute coronary syndrome or myocardial infarction and 9.3% new onset atrial fibrillation. These were associated with increased 90-day mortality [odds ratio (OR), 1.49 95% CI 1.18-1.87, P=0.0006]. Vascular events were independently associated with increased length of hospital stay-median 12 days (IQR 5-22), compared to patients with no vascular events 8 days (IQR 3-17 days, P<0.0001). CONCLUSION: Cardiovascular and cerebrovascular events are common during hospitalization for CAP and are associated with increased 90-day mortality.

Increasing outpatient treatment of mild community-acquired pneumonia: systematic review and meta-analysis.

In order to identify, synthesise and interpret the evidence relating to strategies to increase the proportion of low-risk patients with community-acquired pneumonia treated in the community, we conducted a systematic review of intervention studies conducted between 1981-2010. Articles were included if they compared strategies to increase outpatient care with usual care. Outcomes were: the proportion of patients treated as outpatients, mortality, hospital readmissions, health related quality of life, return to usual activities and patient satisfaction with care. The main analysis included six studies. The interventions in these studies were generally complex, but all involved the use of a severity score to identify low-risk patients. Overall, a significantly larger numbers of patients were treated in the community with these interventions (OR 2.31, 95% CI 2.03-2.63). The interventions appear safe, with no significant differences in mortality (OR 0.83, 95% CI 0.59-1.17), hospital readmissions (OR 1.08, 95% CI 0.82-1.42) or patient satisfaction with care (OR 1.21, 95% CI 0.97-1.49) between the intervention and control groups. There was insufficient data regarding quality of life or return to usual activities. All studies had significant limitations. The available evidence suggests that interventions to increase the proportion of patients treated in the community are safe, effective and acceptable to patients.

Clinically suspected acute pulmonary embolism: a comparison of presentation, radiological features and outcome in patients with and without PE.

BACKGROUND: Relatively little is known about prognosis in patients for whom suspected pulmonary embolism (PE) is refuted by imaging. AIM: This prospective study of suspected PE therefore compared clinico-radiological features and outcome in patients with and without PE. DESIGN AND METHODS: Computed tomographic pulmonary angiography (CTPA) confirmed or refuted PE in consecutive patients. Clinical, laboratory and radiological features were recorded at baseline, and mortality at 1 year determined. Univariate and multivariate analyses identified variables associated with PE. RESULTS: PE was diagnosed in 45 patients and refuted in 141. The PE and 'non-PE' groups were similar with regard to extravascular radiology (though consolidation was significantly more common in the PE group [present in 24 (53%) of the PE group and 42 (30%) of the non-PE group, P < 0.01)], comorbidities (no significant differences), and baseline characteristics (only serum D-dimer concentrations were independently associated with PE by multivariate analysis, P = 0.001). Right ventricular dimensions were significantly higher in the PE group, [right ventricular to left ventricular ratio was 0.98 (range 0.64-2.48) in the PE group and 0.92 (range 0.66-1.95) in the non-PE group, P < 0.05]. In the PE group, right ventricular dimensions rose sharply when 10 or more segmental pulmonary arteries were occluded. One year all-cause mortality was 6.7% in the PE group and 13.5% in the non-PE group (no significant difference, P = 0.218). CONCLUSION: Among a cohort of patients presenting with clinically suspected PE, clinical characteristics, co-morbidities and radiological features were similar when comparing groups with CTPA-proven or CTPA-refuted PE. However RV dimensions, radiological consolidation on imaging and D-dimer levels were significantly higher in the PE group. Patients with suspected PE have a poor prognosis irrespective of whether PE is confirmed. This appears accentuated in patients without PE, a finding possibly under-recognized in clinical practice.