Ulf Kessler
University of Bern
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Featured researches published by Ulf Kessler.
Critical Care | 2009
Fritz Daudel; Ulf Kessler; Hélène Folly; Jasmin S Lienert; Jukka Takala; Stephan M. Jakob
IntroductionThe inflammatory response to an invading pathogen in sepsis leads to complex alterations in hemostasis by dysregulation of procoagulant and anticoagulant factors. Recent treatment options to correct these abnormalities in patients with sepsis and organ dysfunction have yielded conflicting results. Using thromboelastometry (ROTEM®), we assessed the course of hemostatic alterations in patients with sepsis and related these alterations to the severity of organ dysfunction.MethodsThis prospective cohort study included 30 consecutive critically ill patients with sepsis admitted to a 30-bed multidisciplinary intensive care unit (ICU). Hemostasis was analyzed with routine clotting tests as well as thromboelastometry every 12 hours for the first 48 hours, and at discharge from the ICU. Organ dysfunction was quantified using the Sequential Organ Failure Assessment (SOFA) score.ResultsSimplified Acute Physiology Score II and SOFA scores at ICU admission were 52 ± 15 and 9 ± 4, respectively. During the ICU stay the clotting time decreased from 65 ± 8 seconds to 57 ± 5 seconds (P = 0.021) and clot formation time (CFT) from 97 ± 63 seconds to 63 ± 31 seconds (P = 0.017), whereas maximal clot firmness (MCF) increased from 62 ± 11 mm to 67 ± 9 mm (P = 0.035). Classification by SOFA score revealed that CFT was slower (P = 0.017) and MCF weaker (P = 0.005) in patients with more severe organ failure (SOFA ≥ 10, CFT 125 ± 76 seconds, and MCF 57 ± 11 mm) as compared with patients who had lower SOFA scores (SOFA <10, CFT 69 ± 27, and MCF 68 ± 8). Along with increasing coagulation factor activity, the initially increased International Normalized Ratio (INR) and prolonged activated partial thromboplastin time (aPTT) corrected over time.ConclusionsKey variables of ROTEM® remained within the reference ranges during the phase of critical illness in this cohort of patients with severe sepsis and septic shock without bleeding complications. Improved organ dysfunction upon discharge from the ICU was associated with shortened coagulation time, accelerated clot formation, and increased firmness of the formed blood clot when compared with values on admission. With increased severity of illness, changes of ROTEM® variables were more pronounced.
Critical Care | 2009
Sebastian Brandt; T Regueira; Hendrik Bracht; Francesca Porta; Siamak Djafarzadeh; Jukka Takala; José Gorrasi; Erika Borotto; Vladimir Krejci; Luzius B. Hiltebrand; Lukas E. Bruegger; Guido Beldi; Ludwig Wilkens; Philipp M. Lepper; Ulf Kessler; Stephan M. Jakob
IntroductionSeveral recent studies have shown that a positive fluid balance in critical illness is associated with worse outcome. We tested the effects of moderate vs. high-volume resuscitation strategies on mortality, systemic and regional blood flows, mitochondrial respiration, and organ function in two experimental sepsis models.Methods48 pigs were randomized to continuous endotoxin infusion, fecal peritonitis, and a control group (n = 16 each), and each group further to two different basal rates of volume supply for 24 hours [moderate-volume (10 ml/kg/h, Ringers lactate, n = 8); high-volume (15 + 5 ml/kg/h, Ringers lactate and hydroxyethyl starch (HES), n = 8)], both supplemented by additional volume boli, as guided by urinary output, filling pressures, and responses in stroke volume. Systemic and regional hemodynamics were measured and tissue specimens taken for mitochondrial function assessment and histological analysis.ResultsMortality in high-volume groups was 87% (peritonitis), 75% (endotoxemia), and 13% (controls). In moderate-volume groups mortality was 50% (peritonitis), 13% (endotoxemia) and 0% (controls). Both septic groups became hyperdynamic. While neither sepsis nor volume resuscitation strategy was associated with altered hepatic or muscle mitochondrial complex I- and II-dependent respiration, non-survivors had lower hepatic complex II-dependent respiratory control ratios (2.6 +/- 0.7, vs. 3.3 +/- 0.9 in survivors; P = 0.01). Histology revealed moderate damage in all organs, colloid plaques in lung tissue of high-volume groups, and severe kidney damage in endotoxin high-volume animals.ConclusionsHigh-volume resuscitation including HES in experimental peritonitis and endotoxemia increased mortality despite better initial hemodynamic stability. This suggests that the strategy of early fluid management influences outcome in sepsis. The high mortality was not associated with reduced mitochondrial complex I- or II-dependent muscle and hepatic respiration.
Gut | 2011
Luregn J. Schlapbach; Steffen Thiel; Ulf Kessler; Roland A. Ammann; Christoph Aebi; Jens C. Jensenius
In a recent issue of Gut , Muller et al reported on excessive colitis in a murine model of mannan-binding lectin (MBL) deficiency.1 They showed that absence of MBL can lead to uncontrolled intestinal inflammation detrimental to the host. MBL is a pattern-recognition molecule activating the complement system by the lectin pathway. H-ficolin is structurally closely related to MBL and can activate the lectin pathway of complement independently of MBL. While low levels of MBL occur in 10% of Caucasians, H-ficolin deficiency is extremely rare: studies involving over 100 000 adults found no case of H-ficolin deficiency, suggesting it exerts crucial functions for the human immune system.2 The first report on the so far only patient diagnosed with H-ficolin deficiency was published only recently,3 describing a patient with repeated infections who presented …
Molecular Immunology | 2009
Luregn J. Schlapbach; Ulf Kessler; Steffen Thiel; Annette G. Hansen; Mathias Nelle; Roland A. Ammann; Christoph Aebi; Jens C. Jensenius
OBJECTIVE Necrotising enterocolitis (NEC) causes significant mortality in premature infants. The involvement of the innate immune system in the pathogenesis of NEC remains unclear. M-, L- and H-ficolins recognize microorganisms and activate the complement system, but their role in host defense is largely unknown. This study investigated whether ficolin concentrations are associated with NEC. STUDY DESIGN Case-control study including 30 premature infants with NEC and 60 controls. M-, L- and H-ficolins were measured in cord blood using time-resolved immunofluorometric assays. Multivariate logistic regression was performed. RESULTS Of the 30 NEC cases (median gestational age, 29.5 weeks), 12 (40%) were operated and 4 (13%) died. No difference regarding ficolin concentration was found when comparing NEC cases versus controls (p>0.05). However, infants who died of NEC had significantly lower M-ficolin cord blood concentrations than NEC survivors (for M-ficolin <300ng/ml; multivariate OR 12.35, CI 1.03-148.59, p=0.048). In the entire study population, M-, L- and H-ficolins were positively correlated with gestational age (p<0.001) and birth weight (p<0.001). Infants with low M-ficolin required significantly more often mechanical ventilation after birth multivariate (OR 10.55, CI 2.01-55.34, p=0.005). CONCLUSIONS M-, L- and H-ficolins are already present in cord blood and increase with gestational age. Low cord blood concentration of M-ficolin was associated with higher NEC-associated fatality and with increased need for mechanical ventilation. Future studies need to assess whether M-ficolin is involved in multiorgan failure and pulmonary disease.
Pediatric Research | 2008
Luregn J. Schlapbach; Christoph Aebi; Urs Fisch; Roland A. Ammann; Margrith Otth; Susanne Bigler; Mathias Nelle; Steffen Michael Berger; Ulf Kessler
Necrotising enterocolitis (NEC) causes significant morbidity and mortality in premature infants. The role of innate immunity in the pathogenesis of NEC remains unclear. Mannose-binding lectin (MBL) recognizes microorganisms and activates the complement system via MBL-associated serine protease-2 (MASP-2). The aim of this study was to investigate whether MBL and MASP-2 are associated with NEC. This observational case-control study included 32 infants with radiologically confirmed NEC and 64 controls. MBL and MASP-2 were measured in cord blood using ELISA. Multivariate logistic regression was performed. Of the 32 NEC cases (median gestational age, 30.5 wk), 13 (41%) were operated and 5 (16%) died. MASP-2 cord blood concentration ranged from undetectable (<10 ng/mL) to 277 ng/mL. Eighteen of 32 (56%) NEC cases had higher MASP-2 levels (≥30 ng/mL) compared with 22 of 64 (34%) controls (univariate OR 2.46; 95% CI 1.03–5.85; p = 0.043). Higher cord blood MASP-2 levels were significantly associated with an increased risk of NEC in multivariate analysis (OR 3.00; 95% CI 1.17–7.93; p = 0.027). MBL levels were not associated with NEC (p = 0.64). In conclusion, infants later developing NEC had significantly higher MASP-2 cord blood levels compared with controls. Higher MASP-2 may favor complement-mediated inflammation and could thereby predispose to NEC.
Thrombosis Research | 2011
Ulf Kessler; Tamar Grau; Fabrizio Gronchi; Steffen Michael Berger; Sebastian Brandt; Hendrik Bracht; Carlo Marcucci; Zacharias Zachariou; Stephan M. Jakob
INTRODUCTION Although the pig is a standard model for the evaluation of various diseases in humans, including coagulopathy, it is not clear whether results in animals can be extrapolated to man. MATERIALS AND METHODS In 75 anesthetized pigs, we assessed reagent-supported thrombelastometry (ExTEM®), platelet-blocked thrombelastometry (FibTEM®), and aprotinin thrombelastometry (ApTEM®). Results were compared to values from 13 anesthetized humans. RESULTS (MEDIAN, 95% CI): ExTEM®: While clot strength was comparable in pigs (66 mm, 65-67 mm) and in humans (64 mm, 60-68 mm; NS), clotting time in animals was longer (pigs 64 s, 62-66 s; humans 55 s, 49-71 s; P<0.05) and clot formation time shorter (pigs 52 s, 49-54 s; humans 83 s, 67-98 s, P<0.001). The clot lysis index at 30 minutes was lower in animals (96.9%, 95.1-97.3%) than in humans (99.5%, 98.6-99.9%; P<0.001). ApTEM® showed no hyperfibrinolysis in animals. Modification of the anesthesia protocol in animals resulted in significant ExTEM® changes. FibTEM®: Complete platelet inhibition yielded significantly higher platelet contribution to clot strength in pigs (79%, 76-81%) than in humans (73%, 71-77%; P<0.05), whereas fibrinogen contribution to clot strength was higher in humans (27%, 24-29%) than in animals (21%, 19-24%; P<0.05). CONCLUSIONS Maximum clot firmness is comparable in human and porcine blood. However, clot lysis, platelet and fibrinogen contribution to clot strength, as well as initiation and propagation of clotting, are considerably different between pigs and humans. In addition, anesthesic drugs seem to influence thrombelastometry in animals. Accordingly, coagulation abnormalities in pigs subjected to diseases may not necessarily represent the coagulation profile in sick patients.
The Annals of Thoracic Surgery | 2008
Kerstin Seibel; Pascal A. Berdat; Colette Boillat; Bendicht Wagner; Zacharias Zachariou; Ulf Kessler
In a 9-year-old boy, bridging to transplantation was successful with an external biventricular device, the Berlin Heart Excor (Berlin Heart, Berlin, Germany), during a 7-month period. Main long-term complications consisted of infection and hypercoagulability with clotting inside the chambers necessitating six pump exchanges, but without thromboembolic events. This report reviews hemostasis monitoring and management of long-term mechanical circulatory support.
World Journal of Pediatrics | 2016
Ulf Kessler; Franzisca Schulte; Dietmar Cholewa; Mathias Nelle; Stephan C Schaefer; Peter Michael Klimek; Steffen Michael Berger
BackgroundThere is no agreement of the influence of patent ductus arteriosus (PDA) on outcomes in patients with necrotizing enterocolitis (NEC). In this study, we assessed the influence of PDA on NEC outcomes.MethodsA retrospective study of 131 infants with established NEC was performed. Outcomes (death, disease severity, need for surgery, hospitalization duration), as well as multiple clinical parameters were compared between NEC patients with no congenital heart disease (n=102) and those with isolated PDA (n=29). Univariate, multivariate and stepwise logistic regression analyses were performed.ResultsBirth weight and gestational age were significantly lower in patients with PDA [median (95% CI): 1120 g (1009-1562 g), 28.4 wk (27.8-30.5 wk)] than in those without PDA [median (95% CI): 1580 g (1593-1905 g), 32.4 wk (31.8-33.5 wk); P<0.05]. The risk of NEC-attributable fatality was higher in NEC patients with PDA (35%) than in NEC patients without PDA (14%)[univariate odds ratio (OR)=3.3, 95% CI: 1.8-8.6, P<0.05; multivariate OR=2.4, 95% CI: 0.82-2.39, P=0.111]. Significant independent predictors for nonsurvival within the entire cohort were advanced disease severity stage III (OR=27.9, 95% CI: 7.4-105, P<0.001) and birth weight below 1100 g (OR=5.7, 95% CI: 1.7-19.4, P<0.01).ConclusionsIn patients with NEC, the presence of PDA is associated with an increased risk of death. However, when important differences between the two study groups are controlled, only birth weight and disease severity may independently predict mortality.
The Journal of Pediatrics | 2010
Luregn J. Schlapbach; Olaf Ahrens; Peter Michael Klimek; Steffen Michael Berger; Ulf Kessler
regimens evaluated, extensively hydrolyzed protein formula with and without the addition of lactobacillus GG. If baseline values were artificially higher because of the presence of blood, it should have affected stools from both dietary groups equally and thus had no impact on results. Savino et al state that we did not clarify whether patients had anal fissures or gastroesophageal reflux. None of the patients studied had anal fissures, and we are not sure why gastroesophageal reflux had to be ruled out in infants whose only symptoms were blood and mucus in the stool. Finally, Savino et al state that they found higher FC levels in breastfed infants compared with formula-fed infants. That seems to be in contrast with the findings of Campeotto et al, who reported no differences related to type of feeding.
World Journal of Pediatrics | 2009
Ulf Kessler; Marc Ebneter; Zacharias Zachariou; Steffen Michael Berger
BackgroundSepsis is a threatening postoperative complication especially in small infants. Regarding the advances in perinatal medicine, its incidence is unknown to date. We aimed to investigate the incidence, risk factors, laboratory findings and outcome of postoperative sepsis in infants younger than 6 months old.MethodsWe examined postoperative sepsis in babies below 6 months of age during a 4-year period at a tertiary pediatric institution.ResultsThe rate of postoperative sepsis was 6.9%. Laparotomy with enterotomy, thoracotomy and diaphragmatic hernia repair (P<0.05, respectively) as well as low postnatal age and long operation time (P<0.001, respectively) were correlated with the incidence of sepsis. Significant independent predictors for the development of sepsis were the presence of a central venous catheter and perioperative antibiotic treatment (P<0.001, respectively). Coagulase negative Staphylococci were the major infecting organism associated with postoperative sepsis, accounting for 53% of monomicrobial infections. Complete blood counts with differential were not different between infants with sepsis and controls, who had undergone the same surgical procedures. Outcome was favorable in all cases; however, the length of hospital stay was significantly longer in sepsis patients (P<0.05).ConclusionsPostoperative sepsis syndrome is a frequent complication in infants below 6 months of age and causes significant prolongation of hospital stay. Adequate prevention and therapeutic strategies warrant further prospective investigations.