Disease risk and mortality prediction in intensive care patients with pneumonia. Australian and New Zealand practice in intensive care (ANZPIC II)

This study of ventilated patients investigated pneumonia risk factors and outcome predictors in 476 episodes of pneumonia (48% community-acquired pneumonia, 24% hospital-acquired pneumonia, 28% ventilator-associated pneumonia) using a prospective survey in 14 intensive care units within Australia and New Zealand. For community acquired pneumonia, mortality increased with immunosuppression (OR 5.32, CI 95% 1.58-17.99, P < 0. 01), clinical signs of consolidation (OR 2.43, CI 95% 1.09-5.44, P = 0. 03) and Sepsis-Related Organ Failure Assessment (SOFA) scores (OR 1.19, CI 95% 1.08-1.30, P < 0. 001) but improved if appropriate antibiotic changes were made within three days of intensive care unit admission (OR 0.42, CI 95% 0.20-0.86, P = 0.02). For hospital-acquired pneumonia, immunosuppression (OR 6.98, CI 95% 1.16-42.2, P = 0.03) and non-metastatic cancer (OR 3.78, CI 95% 1.20-11.93, P = 0.02) were the principal mortality predictors. Alcoholism (OR 7.80, CI 95% 1.20-1750, P < 0.001), high SOFA scores (OR 1.44, CI 95% 1.20-1.75, P = 0.001) and the isolation of high risk organisms including Pseudomonas aeruginosa, Acinetobacter spp, Stenotrophomonas spp and methicillin resistant Staphylococcus aureus (OR 4.79, CI 95% 1.43-16.03, P = 0.01), were associated with increased mortality in ventilator-associated pneumonia. The use of non-invasive ventilation was independently protective against mortality for patients with community-acquired and hospital-acquired pneumonia (OR 0.35, CI 95% 0.18-0.68, P = 0.002). Mortality was similar for patients requiting both invasive and non-invasive ventilation and non-invasive ventilation alone (21% compared with 20% respectively, P = 0.56). Pneumonia risks and mortality predictors in Australian and New Zealand ICUs vary with pneumonia type. A history of alcoholism is a major risk factor for mortality in ventilator-associated pneumonia, greater in magnitude than the mortality effect of immunosuppression in hospital-acquired pneumonia or community-acquired pneumonia. Non-invasive ventilation is associated with reduced ICU mortality. Clinical signs of consolidation worsen, while rationalising antibiotic therapy within three days of ICU admission improves mortality for community-acquired pneumonia patients.

Australian and New Zealand practice in intensive care (ANZPIC II: The spectrum of practice in the diagnosis and management of pneumonia in patients requiring mechanical ventilation

This study of ventilated patients investigated current clinical practice in 476 episodes of pneumonia (48% community-acquired pneumonia, 24% hospital-acquired pneumonia, 28% ventilator-associated pneumonia) using a prospective survey in 14 intensive care units (ICUs) within Australia and New Zealand. Diagnostic methods and confidence, disease severity, microbiology and antibiotic use were assessed. All pneumonia types had similar mortality (community-acquired pneumonia 33%, hospital-acquired pneumonia 37% and ventilator-associated pneumonia 24%, P = 0.15) with no inter-hospital differences (P = 0.08-0.91). Bronchoscopy was performed in 26%, its use predicted by admission hospital (one tertiary: OR 9.98, CI 95% 5.11-19.49, P < 0.001; one regional: OR 629, CI 95% 3.24-12.20, P < 0.001), clinical signs of consolidation (OR 3.72, CI 95% 2.09-662, P < 0.001) and diagnostic confidence (OR 2.19, CI 95% 1.29-3.72, P = 0.004). Bronchoscopy did not predict outcome (P = 0.11) or appropriate antibiotic selection (P = 0.69). Inappropriate antibiotic prescription was similar for all pneumonia types (11-13%, P = 0.12) and hospitals (0-16%, P = 0.25). Blood cultures were taken in 51% of cases. For community-acquired pneumonia, 70% received a third generation cephalosporin and 65% a macrolide. Third generation cephalosporins were less frequently used for mild infections (OR 0.38, CI 95% 0.16-0.90, P = 0.03), hospital-acquired pneumonia (OR 0.40, CI 95% 0.23-0.72, P < 0.01), ventilator-associated pneumonia (OR 0.04, CI 95% 0.02-0.13, P < 0.001), suspected aspiration (OR 0.20, CI 95% 0.04-0.92, P = 0.04), in one regional (OR 0.26, CI 95% 0.07-0.97, P = 0.05) and one tertiary hospital (OR 0.14, CI 95% 0.03-0.73, P = 0.02) but were more commonly used in older patients (OR 1.02, CI 95% 1.01-1.03, P = 0.01). There is practice variability in bronchoscopy and antibiotic use for pneumonia in Australian and New Zealand ICUs without significant impact on patient outcome, as the prevalence of inappropriate antibiotic prescription is low. There are opportunities for improving microbiological diagnostic work-up for isolation of aetiological pathogens.

The parameterless self-organizing map algorithm

The parameterless self-organizing map (PLSOM) is a new neural network algorithm based on the self-organizing map (SOM). It eliminates the need for a learning rate and annealing schemes for learning rate and neighborhood size. We discuss the relative performance of the PLSOM and the SOM and demonstrate some tasks in which the SOM fails but the PLSOM performs satisfactory. Finally we discuss some example applications of the PLSOM and present a proof of ordering under certain limited conditions.

Successful use of recombinant factor VII in massive hemoptysis due to community-acquired pneumonia

Recombinant activated factor VII (rFVIIa) is a powerful hemostatic agent developed for use in hemophilia. It has been used increasingly in life-threatening hemorrhage in a variety of other settings in which conventional medical or surgical therapy is unsuccessful. This report describes the successful use of rFVIIa for pulmonary hemorrhage due to a focal bleeding source in a regional hospital where bronchial artery embolization or surgery were not available. rFVIIa may be a useful temporizing measure in the unstable patient with pulmonary hemorrhage without coagulopathic bleeding when conventional treatment. is not immediately available.

Double-heater-wire circuits and heat-and-moisture exchangers and the risk of ventilator-associated pneumonia

Objective: To compare the incidence of ventilator-associated pneumonia (VAP) in patients ventilated in intensive care by means of circuits humidified with a hygroscopic heat-and-moisture exchanger with a bacterial viral filter (HME) or hot-water humidification with a heater wire in both inspiratory and expiratory circuit limbs (DHW) or the inspiratory limb only (SHW). Design: A prospective, randomized trial. Setting: A metropolitan teaching hospital's general intensive care unit. Patients: Three hundred eighty-one patients requiring a minimum period of mechanical ventilation of 48 hrs. Interventions: Patients were randomized to humidification with use of an HME (n = 190), SHW (n = 94), or DHW (n = 97). Measurements and Main Results. Study end points were VAP diagnosed on the basis of Clinical Pulmonary Infection Score (CPIS) (1), HME resistance after 24 hrs of use, endotracheal tube resistance, and HME use per patient. VAP occurred with similar frequency in all groups (13%, HME; 14%, DHW; 10%, SHW; p = 0.61) and was predicted only by current smoking (adjusted odds ratio [AOR], 2.1; 95% confidence interval [CI], 1.1-3.9; p =.03) and ventilation days (AOR, 1.05; 95% Cl, 1.0-1.2; p =.001); VAP was less likely for patients with an admission diagnosis of pneumonia (AOR, 0.40; 95% Cl, 0.4-0.2; p =.04). HME resistance after 24 hrs of use measured at a gas flow of 50 L/min was 0.9 cm H2O (0.4-2.9). Endotracheal tube resistance was similar for all three groups (16-19 cm H2O min/L; p =.2), as were suction frequency, secretion thickness, and blood on suctioning (p =.32, p =.06, and p =.34, respectively). The HME use per patient per day was 1.13. Conclusions: Humidification technique does not influence either VAP incidence or secretion characteristics, but HMEs may have air-flow resistance higher than manufacturer specifications after 24 hrs of use.