Rapid hemodilution is associated with increased sepsis and mortality among patients with severe acute pancreatitis

Background Hemoconcentration may be an important factor that determines the progression of severe acute pancreatitis （SAP）. In addition, it has been proposed that biomarkers may be useful in predicting subsequent necrosis in SAP. However, it is still uncertain whether hemodilution in a short term can improve outcome. We aimed to investigate the effect of rapid hemodilution on the outcome of patients with SAP. Methods One hundred and fifteen patients were admitted prospectively according to the criteria within 24 hours of SAP onset. Patients were randomly assigned to either rapid hemodilution （hematocrit （HCT） 〈35%, n=56） or slow hemodilution （HCT 〉35%, n=-59） within 48 hours of onset. Balthazar CT scores were calculated on admission, day 7, and day 14, after onset of the disease. Time interval for sepsis presented, incidence of sepsis within 28 days and in-hospital survival rate were determined. Results The amount of fluid used in rapid hemodilution was significantly more than that used in slow hemodilution （P 〈0.05） on the admission day, the first day, and the second day. There were significant differences between the rapid and slow hemodilution group in terms of hematocrit, oxygenation index, pH values, APACHE II scores and organ dysfunction at different time during the first week. There were significant differences in the time interval to sepsis in rapid hemodilution （（7.4±1.9） days） compared with the slow hemodilution group （（10.2±2.3） days）, and the incidence of sepsis （78.6%） was higher in the rapid group compared to the slow （57.6%） in the first 28 days. The survival rate of the slow hemodilution group （84.7%） was better than the rapid hemodilution （66.1%. P 〈0.05）. Conclusions Rapid hemodilution can increase the incidence of sepsis within 28 days and in-hospital mortality. Hematocrit should be maintained between 30%-40% in the acute response stage.

Sources of multidrug-resistant Acinetobacter baumannii and its role in respiratory tract colonization and nosocomial pneumonia in intensive care unit patients

Background Multidrug-resistant Acinetobacter baumannii （MDRAB） is an important and emerging hospital-acquired pathogen worldwide. This study was conducted to identify the sources of MDRAB and its role in respiratory tract colonization and nosocomial pneumonia in intensive care unit （ICU） patients. Methods We conducted a prospective active surveillance study of MDRAB in three ICUs at a Chinese Hospital from April to August 2011, to identify the sources of MDRAB and its role in respiratory tract colonization and nosocomial pneumonia. Results One hundred and fourteen （13.0%） MDRAB isolates were detected from 876 specimens, with a sensitivity of 11.6% （55/474） in screening of the pharyngeal and tracheal swabs, and 14.7% （59/402） of the sputum/endotracheal aspirates. MDRAB colonization/infection was found in 34 （26.8%） of 127 patients, including 16 （12.6%） cases of pure colonization and 18 （14.2%） cases of pneumonia （two pre-ICU-acquired cases of pneumonia and 16 ICU-acquired cases of pneumonia）. Previous respiratory tract MDRAB colonization was found in 22 （17.3%） patients： eight （6.3%） were pre-ICU-acquired colonization and 14 （11.0%）ICU-acquired colonization. Of eight pre-ICU-colonized patients, five were transferred from other wards or hospitals with hospitalization 〉72 hours, and three came from the community with no previous hospitalization. Overall, 6/22 colonized patients presented with secondary pneumonia; only two （9.1%） colonized MDRAB strains were associated with secondary infections. Respiratory tract MDRAB colonization had no significant relationship with nosocomial pneumonia （P=0.725）. In addition, acute respiratory failure, mechanical ventilation, renal failure, and prior carbapenem use were risk factors for MDRAB colonization/infection. Conclusions A high proportion of cases of MDRAB colonization/infection in ICU patients were detected through screening cultures. About one-third were acquired from general wards and the community before ICU admission. The low incidence of MDRAB colonization-related pneumonia questions the appropriateness of targeted antibiotic therapy.