Clinical characteristics and prognosis of pneumonia and sepsis: multicenter study.

BACKGROUND: Pneumonia is the primary source of sepsis and is significantly associated with mortality. However, only a few studies focus on its clinical characteristics and outcomes. METHODS: We evaluated 500 intensive care unit patients who met severe sepsis or septic shock criteria, dividing them into two distinct groups (43%, sepsis with pneumonia; 41%, sepsis with an infection other than pneumonia). RESULTS: Moderate differences between the groups were observed. The group of sepsis with pneumonia had a higher 28-day in-hospital mortality (41% vs. 30%; P=0.02). Multivariate analysis revealed that the presence of pneumonia associated significantly with mortality (OR 1.76, 95% CI 1.11-2.78) along with cardiopulmonary resuscitation (OR 4.20, 95% CI 1.50-11.74), serum lactate ≥ 3.5 mmol/L (OR 1.92, 95% CI 1.20-3.08), and SOFA score ≥ 12 (OR 2.41, 95% CI 1.52-3.82). Survival analysis revealed for both groups that the patients with PaO2/FiO2 (PF) ratio <170 and lactate ≥ 3.5 mmol/L had a worse prognosis than the patients with PF ratio ≥ 170 and lactate ≥ 3.5 mmol/L or PF ratio <170 and lactate <3.5 mmol/L. CONCLUSION: In patients admitted with sepsis, the pneumonia infection independently predicts 28-day in-hospital mortality. Combining the levels of serum lactate and PF ratio could be a useful approach in predicting mortality of these patients.

Invited article: millimeter-wave bolometer array receiver for the Atacama pathfinder experiment Sunyaev-Zel'dovich (APEX-SZ) instrument.

The Atacama pathfinder experiment Sunyaev-Zel'dovich (APEX-SZ) instrument is a millimeter-wave cryogenic receiver designed to observe galaxy clusters via the Sunyaev-Zel'dovich effect from the 12 m APEX telescope on the Atacama plateau in Chile. The receiver contains a focal plane of 280 superconducting transition-edge sensor (TES) bolometers instrumented with a frequency-domain multiplexed readout system. The bolometers are cooled to 280 mK via a three-stage helium sorption refrigerator and a mechanical pulse-tube cooler. Three warm mirrors, two 4 K lenses, and a horn array couple the TES bolometers to the telescope. APEX-SZ observes in a single frequency band at 150 GHz with 1' angular resolution and a 22' field-of-view, all well suited for cluster mapping. The APEX-SZ receiver has played a key role in the introduction of several new technologies including TES bolometers, the frequency-domain multiplexed readout, and the use of a pulse-tube cooler with bolometers. As a result of these new technologies, the instrument has a higher instantaneous sensitivity and covers a larger field-of-view than earlier generations of Sunyaev-Zel'dovich instruments. The TES bolometers have a median sensitivity of 890 µK(CMB)√s (NEy of 3.5 × 10(-4) √s). We have also demonstrated upgraded detectors with improved sensitivity of 530 µK(CMB)√s (NEy of 2.2 × 10(-4) √s). Since its commissioning in April 2007, APEX-SZ has been used to map 48 clusters. We describe the design of the receiver and its performance when installed on the APEX telescope.