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71.
Nipple stimulation techniques for achieving a contraction stress test were evaluated prospectively in 1271 nipple stimulation contraction stress tests in 753 patients. Success was unrelated to parity, gestational age, or warm, moist towels but was related to the presence of spontaneous prestimulation contractions. Various stimulation techniques were equally successful in achieving a completed test in the presence of prestimulation contractions; however, continuous stimulation was more successful when contractions were absent. Hyperstimulation test results occurred in 21.5% of attempts and increased to 28.8% when bilateral, continuous stimulation was performed.  相似文献   
72.
OBJECTIVE: To determine the pattern of use and satisfaction with community treatment orders (CTOs) by psychiatrists in Saskatchewan. METHOD: All psychiatrists who were licensed to practise by the College of Physicians and Surgeons of Saskatchewan were surveyed by mail in July 1998. RESULTS: The response rate was 72%. The responding psychiatrists were treating 14 patients on CTOs at the time of the survey. Psychiatrists were generally satisfied with the operation of CTOs, though many felt that commitment of only of 3 months before mandatory renewal was too short a period. Almost one-half expected their use of treatment orders to increase. CONCLUSION: While CTOs are used for only a small number of patients in Saskatchewan, they are a clinically useful tool for dealing with a group of otherwise difficult-to-treat patients.  相似文献   
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Integrated interprofessional care teams are the focus of Canadian and American recommendations about the future of health care. Keeping with this, a family medicine teaching site developed an educational initiative to expose trainees to interprofessional care processes and learning (Interprofessional Care Review; IPC). A formative evaluation pilot study was completed using one-on-one interviews and a focus group (n = 6) with family medicine residents. A semi-structured guide was utilized regarding: knowledge, skills and attitudes related to interprofessional care; their experience of the processes utilized in IPC. Data were analyzed using content analysis. Residents' perspectives on their learning revolved around four themes: changes to understanding and practice of interprofessional care; personal impact of IPC; learning about other health professionals; tension and challenges of IPC learning and clinical implementation. Residents valued the educational experience, but identified that faculty supervisors provided "mixed messages" in the value of collaborating with other health professionals. Implications regarding future educational and research opportunities are discussed.  相似文献   
75.
The effect of cotton wool filtration of apheresis platelet concentrates (PCs) on platelet viability and complement activation was evaluated by two laboratories. PCs were prepared by automated (Lab A, n = 5) or manual (Lab B, n = 5) apheresis. After storage for 1 day, the PC was filtered through cotton wool before transfusion on one occasion and, on the other occasion, filtered through a standard screen filter before transfusion to the same donor. Five paired studies were performed by each laboratory. Except for a small, but significant reduction in mean platelet size, from 7.3 +/- 1.1 to 6.6 +/- 0.9 microns 3, after cotton wool filtration, no effect of filtration on various tests of in vitro platelet function and morphologic integrity was found. As demonstrated by autologous radiolabeled studies, no effect of cotton wool filtration on platelet viability was found by Laboratory B, while Laboratory A found a slight increase in the percentage of recovery from 59 +/- 4 to 68 +/- 13 percent, and a small reduction in survival, from 8.2 +/- 0.9 to 7.7 +/- 0.5 days after cotton wool filtration (p less than 0.05). Cotton wool filtration was associated with a slight increase in C3a levels found in manual apheresis PCs. Neither laboratory found any effect of cotton wool filtration per se on the recipients' white cell (WBC) counts or C3a and C5a levels after transfusion.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Fosphenytoin is a prodrug that is metabolized by phosphatases to yield the antiepileptic drug phenytoin plus inorganic phosphate. Thus, fosphenytoin can theoretically alter the electrocardiogram by 2 mechanisms: the direct effects of phenytoin on cardiac conduction and on phosphate binding of calcium, which could indirectly alter cardiac conduction as a result of hypocalcemia. We report the case of a 23-year-old man, weight 73 kg, with a known but untreated seizure disorder who was given prophylactic fosphenytoin, 1500-mg phenytoin equivalents over 85 minutes by intravenous infusion. The patient was normocalcemic before drug infusion. Fosphenytoin produced electrocardiographic changes (prolongation of the ST segment and the QT interval and merging of the T and P waves) consistent with hypocalcemia, and these changes were associated with new-onset reductions in both total and ionized serum calcium concentrations. Plasma phenytoin concentrations were within the therapeutic range during the electrocardiographic changes, and the patient's blood pressure was stable. We interpret these findings as fosphenytoin-related electrocardiographic changes likely attributable to inorganic phosphate-induced hypocalcemia.  相似文献   
78.
OBJECTIVE: We evaluated the effect of two quality improvement interventions (low tidal volume ventilation and restrictive transfusion) on the development of acute lung injury in mechanically ventilated patients. DESIGN: Observational cohort study. SETTING: Three intensive care units in a tertiary academic center. PATIENTS: We included patients who were mechanically ventilated for > or =48 hrs excluding those who refused research authorization or had preexisting acute lung injury or pneumonectomy. INTERVENTIONS: Multifaceted interdisciplinary intervention consisting of Web-based teaching, respiratory therapy protocol, and decision support within computerized order entry. MEASUREMENTS AND MAIN RESULTS: Of 375 patients who met the inclusion and exclusion criteria, 212 were ventilated before and 163 after the interventions. Baseline characteristics were similar between the two groups except for a lower frequency of sepsis (27% vs. 17%, p = .030), trend toward lower median glucose level (140 mg/dL, interquartile range 118-168 vs. 132 mg/dL, interquartile range 113-156, p = .096), and lower frequency of pneumonia (27% vs. 20%, p = .130) during the second period. We observed a large decrease in tidal volume (10.6-7.7 mL/kg predicted body weight, p < .001), in peak airway pressure (31-25 cm H2O, p < .001), and in the percentage of transfused patients (63% to 38%, p < .001) after the intervention. The frequency of acute lung injury decreased from 28% to 10% (p < .001). The duration of mechanical ventilation decreased from a median of 5 (interquartile range 4-9) to 4 (interquartile range 4-8) days (p = .030). When adjusted for baseline characteristics in a multivariate logistic regression analysis, protocol intervention was associated with a reduction in the frequency of new acute lung injury (odds ratio 0.21, 95% confidence interval 0.10-0.40). CONCLUSIONS: Interdisciplinary intervention effectively decreased large tidal volumes and unnecessary transfusion in mechanically ventilated patients and was associated with a decreased frequency of new acute lung injury.  相似文献   
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Background

We report measurements of the temporal response of serum vasopressin concentrations in the period after reperfusion of the liver graft during orthotopic liver transplantation (OLT).

Methods

Vasopressin concentrations were determined in 11 adult patients undergoing OLT by radioimmunoassay of samples collected after induction, at 5 minutes prior to reperfusion, and at 10, 20, 30, 40, 50, 60, 90, and 120 minutes after reperfusion.

Results

Pre-incision vasopressin concentrations ranged from <0.5 to 2.6 pg/mL (reference serum vasopressin, <1.7 pg/mL). Overall, levels increased before reperfusion, but fell thereafter. Individual patients manifested elevated levels during the period after reperfusion. Values immediately before reperfusion exhibited most variability, ranging from 0.8 to 40 pg/mL (median, 15; interquartile range [IQR], 4-29) Median vasopressin concentrations 10 minutes postreperfusion were 7.6 pg/mL (IQR, 3-27). Only 3 of the 11 patients failed to generate vasopressin levels >20 pg/mL. In each of these patients, hemodynamics were satisfactory without the need for additional pressor infusion. Maximum vasopressin concentration measured in any patient was 85 pg/mL. There was no correlation between vasopressin concentration and mean blood pressure or systemic vascular resistance index.

Conclusion

Vasopressin concentrations during OLT vary widely and are elevated periodically during the anhepatic and postreperfusion stages, with no apparent relationship between vasopressin concentrations and blood pressure. Although vasopressin concentrations were not as high as those measured during some other clinical situations, these data suggest that a relative vasopressin deficiency is not a direct cause of hypotension during OLT.  相似文献   
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