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B Dyck

Publications and source records attributed to B Dyck.

12 recordsLinked to original sources
PubMed2000

Characterization of a toxin A-negative, toxin B-positive strain of Clostridium difficile responsible for a nosocomial outbreak of Clostridium difficile-associated diarrhea.

Clostridium difficile-associated diarrhea (CAD) is a very common nosocomial infection that contributes significantly to patient morbidity and mortality as well as to the cost of hospitalization. Previously, strains of toxin A-negative, toxin B-positive C. difficile were not thought to be associated with clinically significant disease. This study reports the characterization of a toxin A-negative, toxin B-positive strain of C. difficile that was responsible for a recently described nosocomial outbreak of CAD. Analysis of the seven patient isolates from the outbreak by pulsed-field gel electrophoresis indicated that this outbreak was due to transmission of a single strain of C. difficile. Our characterization of this strain (HSC98) has demonstrated that the toxin A gene lacks 1.8 kb from the carboxy repetitive oligopeptide (CROP) region but apparently has no other major deletions from other regions of the toxin A or toxin B gene. The remaining 1.3-kb fragment of the toxin A CROP region from strain HSC98 showed 98% sequence homology with strain 1470, previously reported by M. Weidmann in 1997 (GenBank accession number Y12616), suggesting that HSC98 is toxinotype VIII. The HSC98 strain infecting patients involved in this outbreak produced the full spectrum of clinical illness usually associated with C. difficile-associated disease. This pathogenic spectrum was manifest despite the inability of this strain to alter tight junctions as determined by using in vitro tissue culture testing, which suggested that no functional toxin A was produced by this strain.

Adolescent↗
PubMed1999

Regional dissemination and control of epidemic methicillin-resistant Staphylococcus aureus. Manitoba Chapter of CHICA-Canada.

A methicillin-resistant Staphylococcus aureus (MRSA) strain introduced into the largest tertiary-care teaching hospital in Manitoba in 1993 led to a sustained outbreak with secondary outbreaks at one community hospital, two large long-term-care facilities, and nosocomial transmission at a second teaching hospital. Control measures were consistent at each institution and were coordinated on a province-wide basis. MRSA is not currently endemic in any facility in the province.

Cross Infection↗
PubMed1998

Diabetes update with a cardiac perspective.

Diabetes is a chronic illness that affects 6% of the U.S. population. In daily practice, nurses have the opportunity to share with patients and colleagues recent advances in the management of diabetes to improve outcomes. Given the prevalence of heart disease in this population, nurses in the cardiovascular field have the unique opportunity to initiate risk-reduction strategies and collaborate with diabetes team members to optimize qualify of life for patients with diabetes.

Cardiovascular Diseases↗
PubMed1997

Rapid geographic spread of a methicillin-resistant Staphylococcus aureus strain.

In May 1993, an outbreak of methicillin-resistant Staphylococcus aureus (MRSA) was identified at our tertiary care teaching center. The epidemic MRSA strain was transmitted efficiently in the hospital environment. Subsequent investigations indicated that the strain had been introduced into western Canada by a patient who had recently been hospitalized for 3 months in the Punjab, India, and had been admitted to a hospital in rural British Columbia shortly after his arrival in Canada. Transfer of the patient to a hospital in Vancouver and subsequent transfer of a colonized patient contact to a hospital in Winnipeg, Manitoba, resulted in major outbreaks of MRSA at these two large tertiary care centers within 6 weeks of the arrival of the index case in Canada. Epidemiological typing of the S. aureus coagulase gene with use of a polymerase chain reaction method and pulsed-field gel electrophoresis documented clonality of this strain. These outbreaks again illustrate both the propensity of certain strains of S. aureus to produce epidemic disease, including rapid spread within the institutional setting, and the global nature of problems with antimicrobial resistance.

Bacterial Typing Techniques↗
PubMed1997

Nosocomial pneumonia on general medical and surgical wards in a tertiary-care hospital.

OBJECTIVE: To describe the demographic, clinical, and microbiologic characteristics of patients who develop nosocomial pneumonia on general medical and surgical wards of a tertiary-care hospital. DESIGN: A 1-year, prospective, descriptive study. SETTING: A 1,100-bed, tertiary-care, urban hospital. POPULATION: Patients experiencing nosocomial pneumonia were identified through surveillance on general medical and surgical wards, using a standard case definition. RESULTS: 92 pneumonias in 85 patients on general wards were identified. The mean age of patients was 63 +/- 17 years, 55 patients (65%) were male, and 75 cases of pneumonia (81%) were acquired on surgical wards. Bacteremia was identified in 8 (13%) of 62 episodes, and 48 (52%) grew potential pathogens from respiratory specimens. Twenty-six patients (28%) required transfer to the intensive-care unit (ICU), and 20 (22%) received mechanical ventilation. By multivariate analysis, patients with a thoracic surgical procedure or with Staphylococcus aureus isolated from respiratory secretions were more likely to require ICU admission. The overall mortality rate was 20% (17/85), with a directly associated mortality of 14% (12/85). Patients who died were older, more frequently resided on a medical ward, and had a greater mean number of comorbidities. These patients often were treated nonaggressively and were not considered candidates for ICU admission due to advanced age and poor underlying clinical status. CONCLUSIONS: Although the morbidity of nosocomial pneumonia in this population was high, as evidenced by high rates of transfer to ICU, the directly associated mortality was relatively low. Those requiring ICU admission require further study to identify preventive measures that could decrease the morbidity in this group. Interventions to prevent pneumonia or to improve prognosis may not be feasible for the majority of these patients who die from nosocomial pneumonia.

Adult↗
PubMed1992

Respiratory interaction after spinal anesthesia and sedation with midazolam.

The combined use of midazolam and spinal anesthesia is common in clinical practice. Despite the known potential for each to alter ventilation, the effect of their interaction has not been examined. Nineteen healthy volunteers were studied to assess the impact of intravenous midazolam (0.05 or 0.075 mg/kg), spinal anesthesia (T3-T8; mean level, T6), and their combination on resting ventilation and ventilatory responses to progressive hyperoxic hypercapnia. Resting ventilatory pattern was altered significantly by each condition. Midazolam caused a 29% decrease in resting tidal volume and a 24% decrease in mean inspiratory flow rate, while respiratory frequency increased by 14% and minute ventilation remained unchanged. By contrast, spinal anesthesia alone caused a 32% increase in tidal volume, a 24% increase in mean inspiratory flow rate, and a 13% increase in minute ventilation accompanied by a 14% decrease in respiratory frequency. The combination of midazolam and spinal anesthesia caused a significant decrease in minute ventilation (19%), tidal volume (28%), and mean inspiratory flow rate (27%), all of which were significantly more than the predicted sum of the individual interventions. Midazolam and spinal anesthesia each produced a significant decrease in hypercapnic ventilatory response slope, whereas their combination provoked no net change in hypercapnic ventilatory response slope. Interpretation of the hypercapnic ventilatory response data was complicated by shifts in the position of the ventilatory response curve, particularly under the spinal anesthesia condition. It is concluded that intravenous midazolam depresses resting ventilation, spinal anesthesia stimulates resting ventilation, and their combination has a modest synergistic effect of depressing resting ventilation.

Adult↗
PubMed1991

Nosocomial pneumonia in a Canadian tertiary care center: a prospective surveillance study.

OBJECTIVE: To determine the contribution of etiologic agents, including Legionella pneumophila and respiratory viruses to nosocomial pneumonia at a tertiary care center. DESIGN: Prospective surveillance of nosocomial pneumonia with standardized laboratory investigations. SETTING: A 1,100-bed tertiary care center. PATIENTS: All adult inpatients. RESULTS: One hundred and thirty-five Nosocomial pneumonias (5.7/1,000 discharges) were identified. Four (3.0%) were L pneumophila serogroup 1 infections (0.17/1,000 discharges). Legionellosis occurred in non-high-risk patients, and three cases would not have been identified without active surveillance. Viral seroconversion was identified in seven (19%) of 36 cases with specimens available (0.59/1,000 discharges): five influenza B, one influenza A, and one respiratory syncytial virus. IgM serology was positive in one case each for Mycoplasma pneumoniae and Chlamydia species. No geographical clustering was observed for viral infections, and these would not have been identified without active surveillance. Mortality for all nosocomial pneumonia was 25%. Patient factors significantly associated with a poorer outcome included older age, underlying disease, low serum albumin, renal insufficiency, lower platelet count, endotracheal intubation, respiratory failure, bacteremia, and use of antacids. CONCLUSIONS: This prospective surveillance suggested that L pneumophila and viral agents were uncommon causes of nosocomial pneumonia at our institution during this surveillance period.

Adult↗
PubMed1990

Age-related cognitive recovery after general anesthesia.

This study was designed to quantify the rate of mental recovery in elderly and young patients after general anesthesia for intraabdominal surgery (cholecystectomy). Forty patients (25-83 yr) were given four tests assessing neuropsychological function once preoperatively and on five occasions postoperatively. Two of the four neuropsychological tests showed impairment in scores in the elderly patients on the first postoperative day (Symbol Digit Modalities Test, P less than 0.004; The Trail Making Test, P less than 0.03). In addition, one of the tests (Symbol Digit Modalities Test) showed a deterioration in the younger patients (P less than 0.05). The changes that did occur in these tests on the first postoperative day reverted to baseline levels thereafter. There were no significant changes in the remaining two tests, the Mini Mental State Test or the Digit Span Test, at any time in either group. We conclude that postoperative mental deterioration is no greater in elderly than in young patients.

Adult↗