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41.
The authors present a method for obtaining magnetic resonance (MR) images of intra- and extracranial vessels from thin contiguous transaxial sections. A section-selective gradient refocusing pulse sequence with a short repetition time caused flow-related enhancement from spins that flowed perpendicular to the transaxial sections. The signal was further enhanced by means of flow compensation gradients to rephase any phase shifts resulting from moving spins in the presence of the imaging gradients. Coronal and sagittal sections, reformatted from multiple transaxial sections, are shown to have excellent vessel contrast without the use of contrast material. These images were obtained in 12 minutes of acquisition time from as many as 60 sections of 3-mm thickness. Such a technique shows significant promise for MR angiography. 相似文献
42.
McKevitt EC Kirkpatrick AW Vertesi L Granger R Simons RK 《American journal of surgery》2002,183(5):566-570
BACKGROUND: Blunt carotid injuries are rare, often occult, and potentially devastating. Angiographic screening programs have detected this injury in up to 1% of blunt trauma patients. Implementing a liberal angiographic screening program at our hospital is impractical and we want to identify a high-risk group to target for screening. We hypothesize that intracranial and extracranial carotid injuries have different risks, presentations, and outcomes. METHODS: Patients with intracranial and extracranial carotid injuries were identified from the British Columbia trauma registry. Presentation and outcome were reviewed. To facilitate statistical modeling the analysis was done by matching cases to 5 randomly selected controls. Risk factors for injury were evaluated by univariate and multiple logistic regression. RESULTS: A total of 35 carotid injuries were identified. Thirteen intracranial injuries were identified in 10 patients. Twenty-two extracranial injuries were identified in 18 patients. Sixty-seven percent of patients with intracranial injuries and 31% of those with extracranial injuries died (P = 0.11). Eleven percent of intracranial injuries and 56% of extracranial injuries were occult (P = 0.04). Glasgow outcome scores were 2.04 intracranial and 3.12 extracranial (P = 0.18). For intracranial injuries the multiple variable predictive model had two predictors: Glasgow Coma Score =8 and facial fractures. For extracranial the predictors were GCS < or =8 and thoracic injury (Abbreviated Injury Score > or =3). CONCLUSIONS: Intracranial injuries were frequently detected on initial investigations and have very poor outcomes. Extracranial injuries were more frequently occult and stand to benefit from early detection by screening programs. As independent risk factors for these two injuries differ, limited screening resources should focus on risk factors for occult extracranial injury: namely, low GCS and significant thoracic injury. 相似文献
43.
Jodie Wiseman Megan Simons Roy Kimble Zephanie Tyack 《Burns : journal of the International Society for Burn Injuries》2019,45(1):103-113
Background
Current consensus for the ideal pressure range at the pressure garment to scar interface is 15–25 mmHg. Interface pressure variability has been reported at new pressure garment fitting in children. Pressure reductions up to 25% have been recorded over one month in adults.Method
A pilot longitudinal cohort study was completed with children aged less than 18 years receiving pressure garment therapy after burn. Interface pressure was measured at first pressure garment fitting, one month and three months after fitting. Analysis was conducted using Linear Mixed Models.Results
Thirty-four children were recruited to the study, 62% were male. Participants had a median (IQR) age of 3 (6) years. At the first garment fitting, 32% of stationary and 25% of dynamic measurements were within 15–25 mmHg. Pressure variations were recorded at one and three months with scar location (p = 0.03) and %TBSA (p = 0.006) identified as predictors of stationary interface pressure. No statistically significant predictors of dynamic pressure were identified.Discussion
Interface pressure variability was recorded over time during children’s wear of the first pressure garment after burn. Further investigation of factors contributing to pressure changes, subsequent impact on adherence and the effect of sub-optimal pressure application on burn scar outcomes is indicated. 相似文献44.
45.
Elaine C McKevitt Eric Calvert Alex Ng Richard K Simons Andrew W Kirkpatrick Leanne Appleton D Ross G Brown 《Canadian journal of surgery》2003,46(3):211-215
INTRODUCTION: Elderly patients who suffer trauma have a higher mortality and use disproportionately more trauma resources than younger patients. To compare these 2 groups and determine the outcomes and characteristics of elderly patients, we reviewed patients in these 2 groups admitted and treated in our tertiary care provincial trauma centre. METHODS: From the provincial trauma registry we selected a cohort of 40 geriatric patients (group 1) (> or = 65 yr of age) with an ISS of 16 or more who were admitted to and spent time in our trauma service for more than 48 hours and compared them with a similar randomly selected cohort of 44 patients (group 2) aged 20-30 years. Family physicians were contacted for follow-up of these patients 2 years after discharge. We considered length of hospital stay, complications, disposition of the patients and use of consultation services. RESULTS: Patients in group 1 had a mean age of 72.1 years (range from 65-98 yr) and a mean ISS of 27.3 (range from 17-50). Patients in group 2 had a mean age of 26.3 years (range from 22-29 yr) and a mean ISS of 26.3 (range from 17-54). Hospital stay was significantly longer in the group 1: 34.5 days (95% confidence interval [CI]: 24-44 d) versus 21.6 days (95% CI: 15-28 d). More elderly patients experienced complications (35 v. 13, p < 0.001) and required medical consultations (35 v. 26, p < 0.001). In-hospital death rates were 8% (3 of 40) and 4% (2 of 44) respectively (p = 0.3). Fewer geriatric patients could be discharged home (35% [14 of 40] v. 27% [22 of 44], p = 0.056) or to rehabilitation facilities (28% [11 of 40] v. 34% [15 of 44], p = 0.3). Five geriatric patients were discharged to nursing homes (p = 0.007). Of the geriatric patients discharged to rehabilitation facilities or home, 75% were independent 2 years after discharge. CONCLUSIONS: Aggressive care for geriatric trauma patients is warranted, and resources should be directed toward rehabilitation. Based on our findings, we expect that creating a directed care pathway for these patients, targetting complications and earlier discharge, will further improve their outcomes. 相似文献
46.
Brachial plexus examination and localization using ultrasound and electrical stimulation: a volunteer study 总被引:16,自引:0,他引:16
BACKGROUND: Current techniques of brachial plexus block are "blind," and nerve localization can be frustrating and time consuming. Previous studies on ultrasound-assisted brachial plexus blocks are mostly performed with scanning probes of 10 MHz or less. The authors tested the usefulness of a state-of-the-art, high-resolution ultrasound probe (up to 12 MHz) in identifying the brachial plexus in five locations of the upper extremity and in guiding needle advancement to target before nerve stimulation. METHODS: In this prospective observational study, 15 volunteers underwent brachial plexus examination using an L12-L5 MHz probe and a Philips-ATL 5000 ultrasound unit in the interscalene, supraclavicular, infraclavicular, axillary, and midhumeral regions. Thereafter, an insulated block needle was advanced under direct ultrasound guidance to target nerves before confirmation by electrical nerve stimulation in five volunteers in each of the interscalene, supraclavicular, and axillary regions. The quality of brachial plexus images, anatomic variations, and the technique of needle advancement for nerve localization were recorded. RESULTS: The brachial plexus components were successfully identified in the transverse view as round to oval hypoechoic structures with small internal punctuate echos in all regions examined except the infraclavicular area (visualized in 27% of the cases). The authors' technique of advancing the needle in-line with the ultrasound beam allowed moment-by-moment observation of the needle shaft and tip movement at the time of nerve localization. Hypoechoic structures were stimulated electrically and confirmed to be nerves. CONCLUSIONS: These preliminary data show that the high-resolution L12-L5 probe provides good quality brachial plexus ultrasound images in the superficial locations i.e., the interscalene, supraclavicular, axillary, and midhumeral regions. The needle technique described here for ultrasound-assisted nerve localization provides real-time guidance and is potentially valuable for brachial plexus blocks. 相似文献
47.
P.C.G. Simons A.A. Nawijn C.M.A. Bruijninckx B. Knippenberg E.H. de Vries H. van Overhagen 《European journal of vascular and endovascular surgery》2006,32(6):627-633
OBJECTIVE: To determine the safety and the long-term results of primary stent placement for localized distal aortic occlusive disease. DESIGN: Retrospective observational study. PATIENTS AND METHODS: From July 1998 to July 2005 17 patients (14 female and 3 men, mean age 57 years (39-80)) were treated for intermittent claudication. Five of these patients underwent additional endovascular treatment of focal iliac lesions. RESULTS: Technical success defined as residual stenosis of less than 50% or a trans-stenotic systolic pressure gradient <10% was achieved in 14 of 17 (82%) patients. Major complications included dissection at the puncture site in one patient and thrombosis of additional iliac stents in another patient. Both of these complications were successfully treated. During a mean follow-up of 27 months (range 1-86), four patients had recurrence of symptoms due to in-stent restenoses (n=2), femoral (n=1) or iliac occlusion (n=1), respectively. By Kaplan-Meier analysis, primary aortic hemodynamic patency was 83% at 3 years. Secondary aortic hemodynamic patency was 100%. The primary clinical patency was 68% at 3 years. CONCLUSION: Primary stent placement for distal aortic stenoses is an alternative to surgical treatment because of its high patency and relatively low complication rates. 相似文献
48.
M. Witjes A. Kotsopoulos I.H.F. Herold L. Otterspoor K.S. Simons J. van Vliet M. de Blauw B. Festen J.J.A. Eijkenboom N.E. Jansen J.G. van der Hoeven W.F. Abdo 《American journal of transplantation》2017,17(7):1922-1927
Many patients with acute devastating brain injury die outside intensive care units and could go unrecognized as potential organ donors. We conducted a prospective observational study in seven hospitals in the Netherlands to define the number of unrecognized potential organ donors outside intensive care units, and to identify the effect that end‐of‐life care has on organ donor potential. Records of all patients who died between January 2013 and March 2014 were reviewed. Patients were included if they died within 72 h after hospital admission outside the intensive care unit due to devastating brain injury, and fulfilled the criteria for organ donation. Physicians of included patients were interviewed using a standardized questionnaire regarding logistics and medical decisions related to end‐of‐life care. Of the 5170 patients screened, we found 72 additional potential organ donors outside intensive care units. Initiation of end‐of‐life care in acute settings and lack of knowledge and experience in organ donation practices outside intensive care units can result in under‐recognition of potential donors equivalent to 11–34% of the total pool of organ donors. Collaboration with the intensive care unit and adjusting the end‐of‐life path in these patients is required to increase the likelihood of organ donation. 相似文献
49.
50.
The demographics of significant firearm injury in Canadian trauma centres and the associated predictors of inhospital mortality 下载免费PDF全文
Christian J. Finley David Hemenway Joanne Clifton D. Ross Brown Richard K. Simons S. Morad Hameed 《Canadian journal of surgery》2008,51(3):197-203