Carbapenemase-producing Klebsiella pneumoniae bloodstream infection in critically ill patients: risk factors and predictors of mortality.

A significant increase in carbapenemase-producing Klebsiella pneumoniae (CP-Kp) bacteraemias has been observed worldwide. The objective of the present work was to study the risk factors and predictors of mortality of CP-Kp bacteraemias among critically ill patients. During a 4-year period (2012-3015), a matched 1:2 case-control study was conducted. Klebsiella pneumoniae was identified by Vitek 2 technology. Antibiotic susceptibility was performed by the agar disc diffusion method and Etest. The presence of the bla KPC, bla VIM and bla NDM genes was confirmed by polymerase chain reaction (PCR). Epidemiologic data were collected from the intensive care unit (ICU) computerised database. One hundred and thirty-nine patients who developed a CP-Kp bacteraemia were matched with 278 patients. The majority of isolates (128; 92.1%) carried the bla KPC gene, seven carried both bla KPC and bla VIM, three bla VIM and one carried bla NDM. Risk factors for the development of CP-Kp bacteraemia were administration of tigecycline and number of antibiotics administered prior to CP-Kp bacteraemia. Overall, the 30-day mortality was 36.0%. Multivariate analysis revealed septic shock, Simplified Acute Physiology Score II (SAPS II) upon infection onset, adjunctive corticosteroid administration and parenteral nutrition as independent predictors of mortality, while treatment with a combination of appropriate antibiotics was identified as a predictor of good prognosis. Among septic shock patients (n = 74), Sequential Organ Failure Assessment (SOFA) score upon infection onset, adjunctive corticosteroid administration and strain carrying the bla KPC gene were independently associated with mortality, while the administration of combination treatment was identified as a predictor of a good prognosis. The administration of tigecycline predisposes to the induction of bacteraemia. Appropriate antibiotic treatment is associated with better survival, while concomitant corticosteroid treatment is associated with mortality.

Number of positive blood cultures, biofilm formation, and adhesin genes in differentiating true coagulase-negative staphylococci bacteremia from contamination.

The significance of the number of coagulase-negative staphylococci (CNS)-positive blood cultures remains obscure in regards to determining true bacteremia versus contamination. The goal of this study was to determine the predictors of real CNS bloodstream infection among intensive care unit (ICU) patients. ICU patients with at least one CNS-positive blood culture were identified from the microbiology database. Biofilm formation was tested by glass tube and microtiter plate assay. mecA gene, ica operon genes (icaA, icaB, icaD), and adhesin genes (aap, bap, atlE, fbe, fnbA) were detected by polymerase chain reaction (PCR). CNS were recovered from 120 septic episodes, 20 of which were true CNS bacteremias, whereas from the remaining 100 episodes, the isolated CNS were characterized as contaminants. The number of positive blood cultures was significantly associated with true CNS bacteremia. Nineteen true bacteremic Staphylococcus epidermidis strains were compared to 38 contaminants. Biofilm synthesis was documented in 37 isolates associated with the presence of the ica operon (p = 0.048). There were 39, 26, 38, 21, and 10 strains positive for the presence of atlE, bap, fbe, aap, and fnbA genes, respectively. Rifampicin resistance, absence of severe sepsis, number of S. epidermidis-positive blood cultures, and absence of the bap gene were independently associated with true S. epidermidis bacteremia as compared to contaminant strains. The number of positive blood cultures is associated with true CNS bacteremia. The presence of adhesin genes may play a role in differentiating true infection from contamination, whereas absence of the bap gene is associated with true S. epidermidis bacteremia.

Anesthesia management for the super obese: is sevoflurane superior to propofol as a sole anesthetic agent? A double-blind randomized controlled trial.

OBJECTIVE: General anesthesia in obese patients is both challenging and demanding. With the rates of obesity in the general population increasing, more patients undergo bariatric surgery. The aim of this study was to compare the performance, effectiveness and recovery from anesthesia of sevoflurane and propofol in combination with remifentanil, with and without bispectral index (BIS) monitoring in super obese patients undergoing bariatric surgery. PATIENTS AND METHODS: In this prospective, double-blind, randomized, controlled study a total of 100 super obese patients (body mass index, BMI > 50 kg/m2) undergoing bariatric surgery were randomly allocated in four groups: a sevoflurane group (n = 25), a sevoflurane with BIS monitoring group (n = 25), a propofol group (n=25) and a propofol with BIS monitoring group (n=25). Hemodynamic parameters, depth of anesthesia, recovery from anesthesia and postoperative pain were recorded. RESULTS: The mean age of patients was 37.7 ± 9.2 years and the median BMI was 57.86 ± 9.33. There were no statistically significant differences between the four groups with respect to patient characteristics, comorbidities and duration of surgery. The intraoperatively mean arterial pressure was significantly higher in both propofol groups. No significant difference was observed between the four groups in respect to heart rate changes during anesthesia. Although the time to eye-opening and extubation was significantly shorter in both propofol groups, recovery from anesthesia, assessed with the Aldrete, Chung and White recovery scores, was significantly faster in sevoflurane groups. No significant difference was observed in postoperative pain between the four groups. CONCLUSIONS: Although both propofol and sevoflurane provide adequate general anesthesia, sevoflurane may be preferable in super obese patients because of superior hemodynamic stability and faster recovery from anesthesia.

The role of ascorbic acid and exercise in chronic ischemia of skeletal muscle in rats.

This study was designed to investigate the effects of peripheral arterial insufficiency, exercise, and vitamin C administration on muscle performance, cross-sectional area, and ultrastructural morphology in extensor digitorum longus (EDL) and soleus (Sol) muscles in rats. Adult Wistar rats were assigned to ischemia alone (isch), ischemia-exercised (exe), ischemia-vitamin C (vit C), and ischemia-exercise-vitamin C (vit C + exe) groups. Ischemia was achieved via unilateral ligation of the right common iliac artery. Contralateral muscles within the same animal served as controls. Exercise protocol consisted of 50-min intermittent level running performed every other day for 5 days. Vitamin C (100 mg/kg body wt) was administered intraperitoneally on a daily basis throughout the 14 days of the experiment. With regard to the EDL muscle, ischemia alone reduced muscle strength, which was not recovered after vitamin C administration. Exercise alone following ischemia induced the most severe structural damage and cross-sectional area decrease in the muscle, yet the reduction in tetanic tension was not significant. Exercise in conjunction with vitamin C administration preserved ischemia-induced EDL muscle tetanic tension. In the Sol muscle, a significant reduction in single twitch tension after vitamin C administration was found, whereas the tetanic force of the ischemic Sol was not significantly decreased compared with the contralateral muscles in any group. Ischemic Sol muscle cross-sectional area was reduced in all but the exe groups. In Sol, muscle strength was reduced in the vit C group, and mean cross-sectional area of ischemic Sol muscles was reduced in all groups except the exe group. These results illustrate that mild exercise, combined with a low dose of vitamin C supplementation, may have beneficial effects on ischemic EDL muscle with a smaller effect on the Sol muscle.