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31.

Objective

Assess factors that influence both the patient and the physician in the setting of minor head injury in adults and the decision-making process around CT utilization.

Methods

This is a convenience sample survey study of adult minor head injury patients (GCS 15) and their physicians regarding factors influencing the decision to use CT to evaluate for intra-cranial haemorrhage. Once a head CT was ordered and before the results were known, both the patient and physician were given a one-page survey asking questions about their concern for injury and rationale for CT use. CT results and surveys were then recorded in a centralized database and analyzed.

Results

584 subjects were enrolled over the 27-month study period. The rate of any intra-cranial haemorrhage was 3.3%. Both the physicians (6% pre-test estimate) and the patients (22% pre-test estimate) over-estimated risk for haemorrhage. Clinical decision rules were not met in 46% of cases where CT was used. Physicians listed an average of 5 factors from a list of 9 that influenced their decision to order CT. Patients listed an average of 1.7 factors influencing their decision to present to the Emergency Department for evaluation. Many patients felt cost (45%) and low risk stratification (34%) should weigh heavily in the decision to use CT. If asked to limit CT utilization, physicians were able to identify a group with less than 2% risk of injury.

Conclusions

Patients with low risk of intra-cranial injury continue to be evaluated by CT. Physician decision-making around the use of CT to evaluate minor head injury is multi-factorial. Shared decision-making between the patient and the physician in a low risk minor head injury encounter shows promise as a method to reduce CT utilization in this low risk cohort.  相似文献   
32.

Background

Arterial gas embolism (AGE) is a clinical problem that occurs directly in cardiopulmonary bypass machines in open-heart surgeries, or indirectly (through cardiac or pulmonary right to left shunts) in dive accidents, resulting in serious morbidity and even death. Perfluorocarbon (PFC) emulsions have been used for the treatment of AGE in an animal model. We hypothesized that PFC emulsions enhance microvascular blood flow, speed bubble resolution, and oxygenation in AGE compared with saline in a model of cremaster muscle from anesthetized rats.

Materials and methods

AGE was induced by direct air injection into the femoral artery ipsilateral to the studied cremaster muscle. Microhemodynamics, microvascular, and tissue oxygenation were determined before and after treatment with two different commercial PFC emulsions (C10F20, Oxycyte; Oxygen Biotherapeutics, Inc and C10F18, PHER-O2; Sanguine Corporation, Inc) compared with saline in real time using brightfield and phosphorescence microscopy.

Results

Blood pressure and heart rate remained unchanged. Systemic PO2, oxygen (O2) content, and glucose were higher in PFC groups, whereas hematocrit dropped in all groups. Arteriolar blood flow went up 85% and 80% of baseline after C10F20 and C10F18 treatments, respectively, versus 11% after saline treatment. Arteriolar and tissue PO2, and O2 delivery were higher in PFC groups compared with the control group. There was an increase in arteriolar blood flow, reduction in diffusional resistance of O2 in the plasma, and improved tissue oxygenation.

Conclusions

Administration of PFC emulsions in AGE is superior to saline primarily because of surfactant properties along with air bubble reabsorption.  相似文献   
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Introduction and objectives

Lung biopsy is frequently used in the management of children with chronic pulmonary disease to obtain a histological diagnosis. We further evaluate the role of lung biopsy by reviewing our experience of this procedure.

Methods

A retrospective case-note review was carried out of all patients in our regional service under 16 years who underwent a lung biopsy from 1998 to 2011.

Results

Thirty-three children (12 boys) (median 5 years 5 months, range 2 months to 16 years) underwent lung biopsy in the period studied. Following the procedure, 17 patients required ventilation on the intensive care unit for a median of two days (range 1–56 days). Complication rate was 30% (10/33); seven simple pneumothoraces, one tension pneumothorax, and one pneumonia (one child experienced more than one complication). The operative mortality was 12% (4/33). Three children (9%) died within 28 days of surgery. Twenty-six (79%) biopsies provided a definitive histological diagnosis. In 16 (48%) children, the working diagnosis and treatment were changed following lung biopsy.

Conclusion

Lung biopsy has an important role in the management of children with chronic pulmonary disease. However, it carries significant risks which must be considered when assessing the need for histological diagnosis.  相似文献   
35.

Background

As obesity and type II diabetes continue to rise, bariatric surgery offers a solution, but few long-term studies are available. The purpose of this study was to evaluate the long-term outcomes of diabetic patients after gastric bypass.

Materials and methods

This was a retrospective cohort study of all diabetic patients undergoing gastric bypass at our institution, from 1998 to 2012. Patients were compared by postoperative diabetic response to treatment (i.e., response = off oral medication/insulin versus refractory = on oral medication/insulin) and followed at 1-, 3-, 5-, and 10-y intervals. Continuous data were analyzed using Student t-test or Wilcoxon rank-sum test. Multivariable, Cox proportional hazard regression model was performed to compute diabetic cure ratios and 95% confidence intervals.

Results

A total of 2454 bariatric surgeries were performed at our institution during the time period. A total of 707 diabetic patients were selected by Current Procedural Terminology codes for gastric bypass. Mean follow-up was 2.1 y. Incidence of diabetic response was 56% (1 y), 58% (3 y), 60% (5 y), and 44% (10 y). Postoperatively, responsive patients experienced greater percentage of total body weight loss (1 y [P < 0.0001], 3 y [P = 0.0087], and 5 y [P = 0.013]), and less hemoglobin A1c levels (1 y [P = 0.035] and 3 y [P = 0.040]) at follow-up than refractory patients. Multivariable analysis revealed a significant, independent inverse trend in incidence of diabetic cure as both age and body mass index decreased (Ptrend = 0.0019 and <0.0001, respectively). In addition, degenerative joint disease was independently associated with responsive diabetes (cure ratio = 1.6 [95% confidence interval = 1.1–2.2]).

Conclusions

At follow-up, both groups in our study experienced substantial weight loss; however, a greater loss was observed among the response group. Further research is needed to evaluate methods for optimizing patient care preoperatively and improving patient follow-up.  相似文献   
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