Zied Hajjej

Incidence, risk factors and microbiology of central vascular catheter-related bloodstream infection in an intensive care unit

Although there are many studies about catheter related infection in industrialized countries, very few have analyzed it in emerging countries. The aim of our study was to determine the incidence, microbiological profile and risk factors for catheter-related bloodstream infection (CRBSI) in a Tunisian medical intensive care unit. Over eight months (1 January 2012-30 August 2012) a prospective, observational study was performed in an 18-bed medical surgical intensive care unit at Tunis military hospital. Patients who required central venous catheter (CVC) placement for a duration greater than 48 h were included in the study. Two hundred sixty patients, with a total of 482 CVCs were enrolled. The mean duration of catheterization was 9.6 ± 6.2 days. The incidence for CRBSI and catheter colonization (CC) was 2.4 and 9.3 per 1000 catheter days, respectively. Risk factors independently associated with CRBSI were diabetes mellitus, long duration of catheterization, sepsis at insertion and administration of one or more antibiotics before insertion. The mortality rate among the CRBSI group was 21.8%. The predominant microorganisms isolated from CRBSI and CC episodes were Gram negative bacilli. All Gram negative organisms isolated among dead patients in CRBSI group were Extensive Drug Resistant (XDR). In our study the mortality rate among patients with CRBSI was high despite a low incidence of CRBSI. This high rate can be explained by the high-virulent status of Gram negative bacteria involved in CRBSI.

Effects of Levosimendan on Cellular Metabolic Alterations in Patients with Septic Shock: A Randomized Controlled Pilot Study

Introduction: Mitochondrial dysfunction and consequent cellular energetic failure play a key role in the development of sepsis-related organs failure. Evidence suggests that the pleiotropic effects of levosimendan may positively affect cellular metabolism during septic shock. Objectives: To investigate changes in the concentration of glucose, lactate, pyruvate, and glycerol in the extracellular fluid of the skeletal muscle following levosimendan administration in patients with septic shock. Methods: The study was designed as a prospective, double-blind, controlled, clinical pilot trial and performed in a multidisciplinary intensive care unit. After achieving normovolemia and a mean arterial pressure of at least 65 mm Hg, 20 septic shock patients were randomized to receive either levosimendan 0.2 &mgr;g/kg/min (n = 10), or dobutamine 5 &mgr;g/kg/min as active comparator (n = 10). Interstitial tissue concentrations of lactate, pyruvate, glucose, and glycerol were obtained by using muscle microdialysis. All measurements, including data from right heart catheterization, were obtained at baseline and every 6 h for the following 72 h after randomization. The trial is registered with Clinicaltrials.gov, number NCT02963454. Results: Compared with dobutamine, levosimendan increased interstitial tissue pyruvate concentration (153.3 ± 73 and 187. 2 ± 13.5 vs. 210.7 ± 76.2 and 161 ± 64.6; P < 0.05), and lactate clearance (55 vs. 10). Lactate/pyruvate ratio was lower in the levosimendan group at the end of study period (37. 7 ± 18.9 and 29.3 ± 12.7 vs. 10.9 ± 4.5 and 31.4 ± 13. 2; P < 0.05). Conclusion: Although we investigated a small number of patients, our preliminary results suggest that levosimendan may improve cellular metabolic alterations in patients with septic shock.

Successful treatment of a Carbapenem-resistant Klebsiella pneumoniae carrying blaOXA-48, blaVIM-2, blaCMY-2 and blaSHV- with high dose combination of imipenem and amikacin

We describe a case of 58-year-old man with septic shock due to Carbapenem-resistant Klebsiella pneumoniae (CR-Kp) bloodstream infections (BSI) who was successfully treated with a high dose association of amikacin and imipenem combined with continuous venovenous hemodiafiltration (CVVHDF). A Klebsiella pneumoniae (Kp) was isolated from the catheter culture and from two blood samples, drawn from the catheter before removal and from a peripheral vein. The Kp was intermediate to Amikacin (MIC = 16 μg/ml) and was resistant to all other antibiotics including Imipenem (MIC = 4 μg/ml), Colistin (MIC = 16 μg/ml) and Tigecycline (MIC = 4 μg/ml) according to the Clinical and Laboratory Standards Institute (CLSI) published in 2011. PCR amplification and sequencing verified the presence of blaOXA-48, blaVIM-2, blaCMY-2 and blaSHV-1 genes. Amikacin was given at a dose of 30 mg/kg (2.5 g) in a 30 min infusion and the dose of imipenem was increased to 1 g every 6 h despite patients altered renal function (Creatinine Clearance = 25 ml/min). To avoid amikacin nephrotoxicity and to allow the use of high doses of imipenem, continuous venovenous hemodiafiltration (CVVHDF) (blood flow, 200 ml/h; dialysate, 1000 ml/h; ultrafiltrate, 2000 ml/h) was initiated 1 h after the start of the amikacin infusion and continued thereafter. The patient improved hemodynamically and norepinephrine was stopped five days after antibiotherapy adaptation.

Immune suppression in severe infection: level of immunosuppressive cytokine IL10 and IL4 during sepsis and correlation with sequential organ failure assessment score

Introduction : infectious diseases remain a major public health issue in developed and developing countries. The original conceptualization of sepsis as infection with at least 2 of the 4 SIRS criteria focused solely on inflammatory excess. However, the validity of SIRS as a descriptor of sepsis pathobiology has been challenged. Sepsis is now recognized to involve early activation of both pro- and anti-inflammatory responses. Few studies assessed immunosuppressive cytokines during sepsis and their correlation with sequential organ failure assessment score (SOFA). The aim of our work was to study these cytokines mainly IL10 and Il4 during sepsis and correlation with SOFA score. Methods : all patients in sepsis during a period of 12 months were enrolled in a prospective clinical study. Blood samples were collected at two times for IL10 and IL4 (H0 and H24). H0 is the first time for the diagnosis of sepsis in the patients. Serum level was measured by enzyme immunoassay method (EIA) using a commercial Kit (Biosystem ®, Barcelona, Spain). SOFA score was calculated for each patient at H0, H24 and H48. We had used SPSS 11.0. Student t test was statistically significant if p Results : we have included thirty-one patients. There was a correlation between the level of IL10 and SOFA score at H0 (p=0.039). There was an elevation of IL4 during the first 24 h. The mean value of IL4 at H0 was higher than H24: respectively 14.99 pg/ml and 17.66 pg/ml but deference is not significant (p = 0.66) (Fig 1). There isn’t a correlation between IL4 and SOFA score at different time. Conclusion : there was a correlation between the level of IL10 and SOFA score at H0. We found also an elevation of IL4 during first 24h but we don’t found a correlation with SOFA score. Although these are preliminary results, these findings can contribute to a better understanding of physiopathology and outcome. This will allow us to find a new therapeutic target for Immunomodulation, which is the next step in sepsis treatment.

Hemodiafiltration using pre-dilutional on-line citrate dialysate: A new technique for regional citrate anticoagulation: A feasibility study

A prospective, observational, feasibility study was carried out on four patients with end-stage renal failure undergoing bicarbonate hemodialysis to study the feasibility of an on-line hemodiafiltration technique using a citrate dialysate with pre-dilutional infusion of citrate as a technique for regional citrate anticoagulation. All patients had contraindication to systemic heparin anticoagulation. The dialysis technique consisted of an on-line hemodiafiltration with a citrate dialysate without calcium using a Fresenius 4008S dialysis machine and Fresenius Polysulfone F60 dialyzers. The infusion solution was procured directly from the dialysate and was infused into the arterial line. To avoid the risk of hypocalcemia, calcium gluconate was infused to the venous return line. The study was carried out in two stages. During the first stage, the citrate infusion rate was 80 mL/min and the calcium infusion rate was 9 mmol/h. At the second stage, the rates were 100 mL/min and 11 mmol/h, respectively. The primary endpoint of this study was the incidence of thrombosis in the extracorporeal blood circuit and/or the dialyzer. A total of 78 sessions were conducted. All the sessions were well tolerated clinically and there were no major incidents in any of the four patients. At the first stage of the study, there were five incidences of small clots in the venous blood chamber, an incidence of extracorporeal blood circuit thrombosis of 12.5%. At the second stage of the study, no cases of extracorporeal blood circuit or dialyzer thrombosis were noted. Hemodiafiltration with on-line citrate dialysate infusion to the arterial line is safe and allows an effective regional anticoagulation of the extracorporeal blood circuit without the need for systemic anticoagulation.

Inherited thrombophilia-related complications in the treatment of a biatrial thrombus.

The study emphasizes the importance of the high risk of thromboembolism with inherited thrombophilic factors. Transesophageal echocardiography revealed large biatrial masses in an 87-year-old woman with history of nonvalvular atrial fibrillation, pulmonary embolism, and prescribed oral anticoagulation for prophylaxis of embolic events. The surgical removal of the presumed thrombus was declined by the patient and intravenous anticoagulation with unfractionated heparin was initiated. Treatment was complicated by additional embolic events and the patient succumbed after 14 days due to multiple organ failure. Testing revealed heterozygosity for both the factor V Leiden and the methylenetetrahydrofolate reductase C677T mutations inducing resistance to activated protein C. The combination of these thrombophilic factors can probably explain the poor anticoagulant response, embolic events, and the failure of resolution of the biatrial masses.