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A Wilmer

Publications and source records attributed to A Wilmer.

At least 19 recordsLinked to original sources
PubMed2006

Review article: non-biological liver support in liver failure.

Liver failure, whether acute or acute-on-chronic, remains an important cause of morbidity and mortality. The lack of liver detoxification, metabolic and regulatory functions of the liver leads to life-threatening complications, such as renal failure, altered immune response, hepatic coma and systemic haemodynamic dysfunction, eventually culminating in multiorgan failure. Current medical therapy involves the management of the precipitating event and treatment of complications until the liver eventually recovers, leaving us with no other treatment options than transplantation if these attempts fail. However, the shortage in cadaveric organs and other transplant-related problems, have prompted the need for alternative methods to provide liver support. As liver failure is often potentially reversible, considerable effort has been invested in the development of liver support systems. Currently, most of the experience is available for non-biological support systems. They represent the focus of this review, which aims to define the goals of liver support, to describe the design of the different existing devices and to analyse the available data to determine their current status in the management of patients with liver failure.

Albumins↗
PubMed2004

Pharmacokinetics of remifentanil and its major metabolite, remifentanil acid, in ICU patients with renal impairment.

BACKGROUND: The pharmacokinetics of remifentanil, an opioid analgesic metabolized by non-specific esterases, and its principal metabolite, remifentanil acid (RA), which is excreted via the kidneys, were assessed as part of an open-label safety study in intensive care unit (ICU) patients with varying degrees of renal impairment. METHODS: Forty adult ICU patients with normal/mildly impaired renal function (creatinine clearance [CL(cr)] 62.9 (sd) 14.5 ml min(-1); n=10) or moderate/severe renal impairment (CL(cr) 14.7 (15.7) ml min(-1); n=30) were included. Remifentanil was infused for up to 72 h, at a starting rate of 6-9 microg kg(-1) h(-1) titrated to achieve a target sedation level, with additional propofol (0.5 mg kg(-1) h(-1)) if required. Intensive arterial sampling was performed for up to 72 h after infusion. Pharmacokinetic parameters obtained by simultaneous modelling of remifentanil and RA data were statistically compared between the two groups. RESULTS: Remifentanil pharmacokinetics were not significantly affected by renal status. RA clearance in the moderate/severe group was reduced to about 25% that of the normal/mild group (41 (29) vs 176 (49) ml kg(-1) h(-1), P<0.0001). Metabolic ratio, a predictor of the ratio of RA to remifentanil concentrations at steady state, was approximately eight-fold higher in the moderate/severe group relative to the normal/mild group (116 (110) vs 15 (4), P<0.0001). Maximum RA levels approached 700 ng ml(-1) in the moderate/severe group. CONCLUSIONS: Although RA accumulates in patients with moderate/severe renal impairment, pharmacokinetic modelling predicts that RA concentrations during a 9 microg kg(-1) h(-1) remifentanil infusion for up to 15 days would not exceed those reported in the present study, for which no associated prolongation of mu-opioid effects was observed.

Adolescent↗
PubMed2002

A survey on gastroenterology training in Europe.

BACKGROUND: Specialist training in gastroenterology and hepatology is not standardised in different European countries. AIM: The aim of this survey was to assess the different teaching and socioeconomic aspects of training programmes in Europe. METHODS: Seventy questionnaires were distributed to last year trainees or newly graduated gastroenterologists. Forty two respondents (60%) from 34 major training centres in 10 different European countries replied. RESULTS: Overall, the data revealed major diversity for all aspects analysed, between and within the different European countries. Both the duration of training (range 4-10.4 years) and workload (range 48.5-89.2 hours per week) differed markedly between countries. The average number of endoscopic procedures (gastroscopies, range 300-2600; colonoscopies, range 73-550; endoscopic retrograde cholangiopancreatographies, range 1-385) differed also. One third of last year trainees reported that they felt uncertain in some endoscopic procedure. The European trainee was on call for 5-6 nights a month on average (range 1-8). Monthly wages differed considerably between countries, ranging from 767 to 2180 Euro. CONCLUSION: We found major differences in the professional aspects and socioeconomic conditions of gastroenterologist/hepatologist training in 10 different European countries, probably leading to differences in quality of training. In several countries or centres the average number of procedures was below the threshold issued by the European Board of Gastroenterology or the American Gastroenterological Association. Issuing a European diploma for gastroenterology is a valuable effort towards meeting this problem. Further studies are needed to re-evaluate the training programmes in Europe and to define threshold numbers and technical end points for assessment of endoscopic skills.

Adult↗
PubMed2001

Frequency of transient streptococcal bacteremia following urgent orotracheal intubation in critically ill patients.

OBJECTIVES: To examine whether urgent orotracheal intubation (OI) can induce bacteremia. To find predictive factors for post-intubation bacteremia. DESIGN: Prospective observational study. SETTING: Seventeen-bed medical intensive care unit in a university hospital. PATIENTS: Sixty-eight adult intensive care patients undergoing urgent OI. MEASUREMENTS AND RESULTS: Patients in need of OI could be included if no cardiopulmonary resuscitation was performed. A blood culture was taken immediately before, as soon as possible after, and 60 min after intubation. The indication for intubation, ease of intubation, and the antibiotics used before intubation were registered. Six patients (6/68 or 9%) had streptococcal bacteremia immediately (mean 10.8 min) after intubation. No patient (0/62) had streptococcal bacteremia 60 min after intubation (P = 0.01). Four of the six patients showing streptococcal bacteremia after intubation were intubated by a second doctor because of difficulties during intubation, whereas this was the case in only 9/62 in those without streptococcal bacteremia (P = 0.01). Four of the 13 patients (31%) who needed to be intubated by a second doctor showed transient streptococcal bacteremia. Of the 20 patients not receiving antibiotics at the time of intubation, four (20%) had streptococcal bacteremia compared with 2/47 (4.2%) patients receiving antibiotics (P = 0.06). CONCLUSIONS: Urgent intubation can cause transient bacteremia with streptococci in a significant proportion of intensive care patients. The observed frequency of bacteremia is higher than previously reported after elective intubation. The difficulty of intubation is probably a predisposing factor.

Bacteremia↗
PubMed2001

Difference in time to positivity of hub-blood versus nonhub-blood cultures is not useful for the diagnosis of catheter-related bloodstream infection in critically ill patients.

OBJECTIVE: The differential time to positivity (DTTP), defined as the difference in time necessary for the blood cultures taken by a peripheral puncture and through the catheter to become positive has been suggested to be useful in differentiating between catheter-related bloodstream infection (CR-BSI) and other sources of bacteremia. A DTTP of >120 mins was found predominantly in CR-BSI. The objective of our study was to investigate whether DTTP is useful for the diagnosis of CR-BSI in a medical-surgical intensive care unit. DESIGN: Prospective clinical study. SETTING: A 60-bed medical-surgical intensive care unit of a university hospital. PATIENTS: One hundred consecutive adult patients from whom catheter(s) were to be removed for suspected CR-BSI were studied. INTERVENTION: A blood culture (using aerobic and anaerobic culture bottles) was first taken from a new puncture site. Next, a blood culture was taken through every intravascular catheter in place. MEASUREMENTS AND RESULTS: DTTP was calculated using the automated BacT/Alert blood culture system. Three patients had CR-BSI and nine patients had noncatheter-related bacteremia. Five patients had catheter-related sepsis without proven bacteremia. There was no significant difference in median DTTP between patients with CR-BSI and noncatheter-related bacteremia (2.1 hrs and 3.3 hrs, respectively; p =.6). Moreover, catheter-related sepsis in patients without bacteremia could not be detected using DTTP. CONCLUSION: DTTP seems not to be useful for the diagnosis of CR-BSI in a medical-surgical intensive care unit.

Adult↗
PubMed2001

Perception of changes in wall tension of the proximal stomach in humans.

BACKGROUND: Hypersensitivity to distension of the stomach is a frequent finding in functional dyspepsia. During gastric distension studies both wall tension and elongation are increased. AIM: We wished to distinguish changes in wall tension from changes in elongation in the genesis of perception of mechanical stimuli originating from the proximal stomach in healthy subjects. SUBJECTS AND METHODS: Twenty six volunteers were studied using gastric barostat and antroduodenal manometry. In 14 subjects, stepwise isobaric and isovolumetric distensions were performed before and during erythromycin infusion. In all volunteers, on a separate occasion, phasic contractions of the proximal stomach were detected as intraballoon pressure increases during fixed volume inflation. These contractions were matched with perception changes during two 10 minute periods, before and during administration of erythromycin. RESULTS: Erythromycin significantly lowered the perception and discomfort thresholds during stepwise gastric distension. During fixed volume inflation, erythromycin increased the number and amplitude of fundic contractions and enhanced their perception from 51.1 (7.4)% to 64.0 (4.7)%. The proportion of perception score increases coinciding with fundic contractions increased from 47.3 (0.7)% to 81.5 (0.5)%. The amplitude of correctly identified isolated fundic pressure waves was higher compared with non-identified waves. CONCLUSIONS: These results support the hypothesis that changes in gastric wall tension may be involved in the genesis of symptoms originating from the stomach.

Adult↗
PubMed2000

Generation of reactive oxygen species by Candida albicans in relation to morphogenesis.

Candida albicans is able to generate significant amounts of reactive oxygen species (ROS). In this study, ROS generation by yeast and hyphal forms of the strain 3153 A was analyzed to determine whether ROS generation could be a major factor in the invasive behavior of germinative cells. Furthermore, the virulent strain CA6 and its avirulent and agerminative mutant VIR3 were compared. ROS were measured by lucigenin-enhanced chemiluminescence and a cytochrome c assay. During the blastoconidial phase of all strains moderate amounts of ROS were found at cell concentrations > 1 x 10(5)/ml. However, ROS generation appeared to be specifically inhibited at cell concentrations > 1 x 10(8)/ml, and this was found in both assays. As shown in comparative experiments, the medium used for measurement markedly affected the total amount of ROS. Hyphae of strain 3153 A generated a significantly higher amount of ROS than yeast cells and cells with germ tubes (P < 0.001). The strain CA6 showed significantly higher ROS generation than the VIR3 strain for both blastoconidiae and after 30 min of induction of hypha formation (P < 0.05). In conclusion, hypha formation, usually acknowledged as a major factor in Candida pathogenicity, was associated with markedly increased ROS formation. ROS generation was not closely linked to the ability to form hyphae, but was highest in germinative cells.

Candida albicans↗
PubMed2000

Thrombocytopenia and prognosis in intensive care.

OBJECTIVE: To study the incidence and prognosis of thrombocytopenia in adult intensive care unit (ICU) patients. DESIGN: Prospective observational cohort study. SETTING: The medical ICU of a university hospital and the combined medical-surgical ICU of a regional hospital. PATIENTS: All patients consecutively admitted during a 5-month period. INTERVENTIONS: Patient surveillance and data collection. MEASUREMENTS AND MAIN RESULTS: The primary outcome measure was ICU mortality. Data of 329 patients were analyzed. Overall ICU mortality rate was 19.5%. A total of 136 patients (41.3%) had at least one platelet count <150 x 10(9)/L. These patients had higher Multiple Organ Dysfunction Score (MODS), Simplified Acute Physiology Score (SAPS) II, and Acute Physiology and Chronic Health Evaluation (APACHE) II scores at admission, longer ICU stay (8 [4-16] days vs. 5 [2-9] days) (median [interquartile range]), and higher ICU mortality (crude odds ratio [OR], 5.0; 95% confidence interval [CI], 2.7-9.1) and hospital mortality than patients with daily platelet counts >150 x 10(9)/L (p < .0005 for all comparisons). Bleeding incidence rose from 4.1% in nonthrombocytopenic patients to 21.4% in patients with minimal platelet counts between 101 x 10(9)/L and 149 x 10(9)/L (p = .0002) and to 52.6% in patients with minimal platelet counts <100 x 10(9)/L (p < .0001). In all quartiles of admission APACHE II and SAPS II scores, a nadir platelet count <150 x 10(9)/L was related with a substantially poorer vital prognosis. Similarly, a drop in platelet count to < or =50% of admission was associated with higher death rates (OR, 6.0; 95% CI, 3.0-12.0; p < .0001). In a logistic regression analysis with ICU mortality as the dependent variable, the occurrence of thrombocytopenia had more explanatory power than admission variables, including APACHE II, SAPS II, and MODS scores (adjusted OR, 4.2; 95% CI, 1.8-10.2). CONCLUSIONS: Thrombocytopenia is common in ICUs and constitutes a simple and readily available risk marker for mortality, independent of and complementary to established severity of disease indices. Both a low nadir platelet count and a large fall of platelet count predict a poor vital outcome in adult ICU patients.

Aged↗
PubMed2000

Influence of sumatriptan on gastric fundus tone and on the perception of gastric distension in man.

BACKGROUND: In animals, activation of 5-HT(1) like receptors causes a relaxation of the gastric fundus through the activation of intrinsic inhibitory neurones. AIMS: To investigate the effect of sumatriptan, an agonist at enteric neuronal 5-HT(1) receptors, on fasting fundus tone and sensitivity to gastric distension in man. METHODS: A gastric barostat was used to study the effect of placebo and sumatriptan, 6 mg subcutaneously, on basal fundic tone in healthy subjects. In addition, stepwise isobaric and isovolumetric gastric distensions were performed and perception was measured before and after the administration of placebo and sumatriptan. RESULTS: Placebo had no significant effects on gastric tone and on perception. Sumatriptan induced an immediate relaxation of the gastric fundus, reflected by an intragastric volume increase of 209 (39) ml (p<0.0005). After sumatriptan, intragastric pressures at the thresholds for perception or discomfort were not significantly altered. However, the intragastric volumes and the corresponding calculated wall tensions at perception and discomfort thresholds were significantly increased. CONCLUSIONS: Administration of the 5-HT(1) receptor agonist sumatriptan induces a relaxation of the gastric fundus in man, allowing larger intragastric volumes before thresholds for perception or discomfort are reached. The effects of sumatriptan on the gastric fundus may have therapeutic potential in the treatment of patients with functional dyspepsia.

Adult↗
PubMed2000

Comparison of premortem clinical diagnoses in critically iII patients and subsequent autopsy findings.

OBJECTIVE: To determine whether our practice of requesting an autopsy for patients who die in the medical intensive care unit (MICU) continues to be a valid approach to obtain clinically and educationally relevant findings. METHODS: In this retrospective study conducted in an adult MICU population of a university hospital, the clinical diagnoses and postmortem major diagnoses of 100 patients who died in 1996 (autopsy rate of 93%) were compared. RESULTS: Eighty-one percent of the clinical diagnoses were confirmed at autopsy. In 16%, autopsy findings revealed a major diagnosis that, if known before death, might have led to a change in therapy and prolonged survival (class I missed major diagnoses). The most frequent class I missed major diagnoses were fungal infection, cardiac tamponade, abdominal hemorrhage, and myocardial infarction. Another 10% of autopsies revealed a diagnosis that, if known before death, would probably not have led to a change in therapy (class II error). CONCLUSIONS: Autopsy remains an important tool for education and quality control. In contrast with historical series of 1 to 2 decades ago, there is a clear shift in the type of class I missed major diagnoses toward opportunistic infections. Bedside-applicable techniques such as electrocardiography with supplemental posterior leads, echocardiography, and meticulous abdominal ultrasonography might improve the outcome in selected MICU patients.

Adolescent↗
PubMed1999

Duodenogastroesophageal reflux and esophageal mucosal injury in mechanically ventilated patients.

BACKGROUND & AIMS: Esophagitis has been reported to be the most frequent cause of upper gastrointestinal bleeding in intensive care patients. The mechanisms causing esophagitis are unclear. The aim of this study was to measure esophageal acid and bile reflux and to examine the relationship between reflux and mucosal injury in mechanically ventilated patients. METHODS: Twenty-five critically ill, mechanically ventilated patients with nasogastric tubes were prospectively included for 24-hour esophageal pH and duodenogastroesophageal bile reflux studies (Bilitec 2000 system). All patients received acid-suppressive therapy for stress ulcer prophylaxis with ranitidine. On the day before the study, patients underwent esophageal endoscopy to determine the presence or absence of esophagitis. RESULTS: After approximately 5 days of mechanical ventilation, 12 patients (48%) had erosive esophagitis, 2 patients had pathological acid reflux, and 12 patients had pathological bile reflux. The presence of esophagitis was significantly associated with pathological bile reflux (P = 0.017, Fisher exact test). The severity of esophagitis was significantly correlated with the volume of gastric residual volume and with increasing times of bile reflux. The latter was significantly correlated with the number of organ failures. CONCLUSIONS: Despite acid-suppressive therapy, esophagitis is a frequent finding in critically ill patients after less than a week of mechanical ventilation. In these patients, besides mechanical irritation by the nasogastric tube, chemical injury caused by duodenogastroesophageal reflux seems to have a major role in the pathogenesis of esophageal mucosal lesions.

Acids↗
PubMed1998

Varicella-zoster virus infection associated with acute liver failure.

Although acute liver failure due to the varicella-zoster virus is rare, it is frequently fatal. Immunologic impairment is a significant predisposing factor. Classic symptoms at presentation are rash, abdominal pain, and fever. After some days patients go on to develop full-blown liver failure. The diagnosis can be confirmed by histological examination and electron microscopy with fluorescent staining, immunohistochemistry, and in situ hybridization of the liver. In cases of high suspicion, acyclovir therapy should not be delayed.

Adult↗
PubMed1998

[Systemic terbinafine treatment of dermatophytoses in children].

Terbinafine is the first orally active allylamine. Though it is available since several years, experience in children is rather limited. We report about five cases of dermatophytoses in children successfully treated with oral terbinafine. Five children (age: 10 month to 14 years) with a clinical and mycological diagnosis of dermatophytosis were treated with oral terbinafine according to their body weight: 250 mg/d (< 40 kg), 125 mg/d (20-40 kg) and 62.5 mg/d (< 20 kg). The course of treatment was 2 to 4 weeks. In 2/5 patients previous systemic treatment with oral griseofulvin failed. Terbinafine therapy resulted in a complete clearance of mycotic infections (both clinical and mycological) in 5/5 children. No unwanted side-effects were observed. During a nine month follow-up no relaps occurred. In our five cases tolerability, clinical and mycological response of terbinafin therapy were excellent. Its penetration into sebum and only slow release from skin glands may explain the efficacy even in short-time therapy.

Administration, Oral↗
PubMed1998

Actions of the 5-hydroxytryptamine 1 receptor agonist sumatriptan on interdigestive gastrointestinal motility in man.

BACKGROUND: Pharmacological studies of the enteric nervous system have shown the presence of several subtypes of 5-hydroxytryptamine (5HT) receptor, which might be involved in control of the migrating motor complex. AIMS: To study the effect of sumatriptan, an agonist of enteric neuronal 5HT1p receptors, on interdigestive motility in man. SUBJECTS AND METHODS: In 12 healthy subjects, interdigestive motility was recorded manometrically in the upper gastrointestinal tract. In seven subjects blood samples were drawn every 15 minutes for radioimmunoassay of motilin and somatostatin. After two phase 3s of the migrating motor complex, 6 mg of sumatriptan was administered subcutaneously. Recording continued until two more phase 3s had occurred. RESULTS: Sumatriptan induced a premature phase 3 in the jejunum after a median of 10 (8) minutes. The duration of the migrating motor complex cycle was shortened at the expense of phase 2. After sumatriptan, plasma somatostatin concentrations were reduced and gastric phase 3s were suppressed, although median motilin concentrations and the occurrence of plasma motilin peaks were not affected. Phase 3s of the migrating motor complex preceding sumatriptan were associated with motilin peaks, while phase 3s after sumatriptan were not. Furthermore, pretreatment with sumatriptan prevented the induction of a gastric phase 3 by the motilin agonist erythromycin. CONCLUSIONS: Administration of the 5HT1P receptor agonist sumatriptan induces a premature intestinal phase 3, suppresses gastric phase 3s, prevents induction of a gastric phase 3 by erythromycin, and reduces plasma somatostatin concentrations.

Adult↗