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1.

Objectives

Iatrogenic injury of the Profunda Femoris Artery (PFA) at time of hip fixation surgery can increase morbidity and mortality and prolong the hospital stay. This is an injury that tends to pass unnoticed as a cause of postoperative deterioration despite being frequently reported in the literature. Our study aims to describe the anatomy of the PFA in relation to the medial femoral cortex with specific emphasis on its orientation relative to the position of a sliding hip screw side plate construct. By doing so we are able to present clear guidance to orthopaedic surgeons on how to avoid iatrogenic PFA injury at the time of hip fracture fixation.

Methods

Using Computed Tomography Angiographic (CTA) studies, the course of the PFA in relation to the medial femoral cortex was traced in 44 patients (28 males and 16 females) with mean age of 65.6 years. Coronal and axial CT sections were cross-linked to specify the position of the PFA at 1?cm intervals.

Results

The course of the artery could be divided into three parts relative to a fixed reference point. Proximal and distal parts of the artery were in a safer position in comparison to the middle part of the artery that was found very close to the femoral cortex and along the coronal axis of the femur (mean angle 2.9° from the femoral coronal axis and 13.8?mm from the medial femoral cortex). Using the commercially available side plate constructs, this part of the artery corresponded to the distal part of the plate (third and fourth holes).

Conclusion

Special attention needs to be practiced by the operating surgeon while drilling into the third and fourth holes of the side plate.  相似文献   
2.
Radiolabeled octreotide analogs (Oct) and metaiodobenzylguanidine (MIBG) offer 2 different approaches for imaging and targeting metastatic gastroenteropancreatic neuroendocrine tumors (GEP-NET). Despite successful establishment of the revised World Health Organization (WHO) classification, which distinguishes between low- and high-grade malignant GEP-NET, there is a lack of scintigraphic studies comparing uptake behavior on the basis of this categorization. This study aims to define predisposing factors of tracer uptake for both imaging principles implementing the updated tumor criteria of the current WHO classification. METHODS: Fifty-seven consecutive patients with histologically confirmed metastatic GEP-NET evaluated with both 111In-pentetreotide and 123I/131I-MIBG scintigraphy were included in this study. Intensity of tracer uptake was graded according to the different metastatic regions. Patients were classified as overall positive when avid uptake in the clinically relevant tumor lesions was present. Correlation was tested between the proportion of positive patients and tumor origin, function, and malignancy. RESULTS: Overall, 52 patients (91.2%) were Oct positive and 28 patients (49.1%) were MIBG positive. The proportion of tracer-positive patients was significantly higher (P < 0.05) in low-grade malignant tumors for both tracers and in functioning as well as in gastroenteral NET for MIBG. Five patients were negative for both tracers. None of the Oct-negative patients proved to be MIBG positive. CONCLUSION: Oct affinity is observed with high frequency throughout the subgroups of metastatic GEP-NET, whereas corresponding MIBG uptake is overall less prevalent and more group dependent. Tumor differentiation significantly impacts both Oct and MIBG uptake, whereas functionality predisposes only for MIBG accumulation. Though clearly inferior to Oct-based radioimaging in most GEP-NET, MIBG achieves a remarkable rate of radioligand accumulation in functioning midgut enterochromaffin cell metastases (>80% of patients positive). These results may have implications for patient management and potentially for selection and performance of targeted therapy.  相似文献   
3.
PURPOSE: To present the anesthetic management for the correction of a ventricular septal defect (VSD) in a patient with multiple acyl CoA dehydrogenase deficiency (glutaric aciduria type II; GAII). A review of the literature about anesthetic management of patients with mitochondrial diseases undergoing cardiopulmonary bypass (CPB) is also included. Clinical features: An 11-yr-old girl with GAII manifested as severe hypoglycemia since she was a newborn and generalized muscle weakness. She underwent open-heart surgery for VSD correction with CPB. The anesthetic management avoided inhalational anesthetics, maintained the blood sugar within normal limits and continued normothermia during CPB in order to avoid the stress of hypothermia for her abnormal mitochondria. The patient tolerated the procedure well and experienced a good recovery. CONCLUSION: The anesthetic management of patients with any mitochondrial disease requires normoglycemia, normothermia and the avoidance of metabolic stress in order to preserve energy production by the diseased mitochondria.  相似文献   
4.
Cardiovascular diseases are the leading cause of death in the United States and most other Western countries. In the United States alone, more than 1 million annual deaths and as many as three times that number of serious consequences can be attributed to these conditions. To provide care to patients with cardiovascular disease, oral health care providers must understand the disease, its treatment, and its impact on the patient's ability to undergo and respond to dental care.  相似文献   
5.
Hypothermia and preservative perfusates have been used to decrease ischemic renal injury. This study was performed to identify the preservative function of perfusates independent of the effects of hypothermia. Rats underwent 45 minutes of renal ischemia. Rectal and renal parenchyma temperatures were monitored and maintained within 1° C of normal. Perfusates were University of Wisconsin solution (UW), Euro-Collins solution, normal saline solution, and Ringer's lactate solution. A nonperfused ischemic control and a nonischemic control group were also evaluated. Parameters evaluated included serum creatinine and blood urea nitrogen levels, renal ischemic injury grade, renal weight, and gross appearance of the injured kidney. Rats treated with UW solution were found to have a significantly lower creatinine, blood urea nitrogen, and injury grade than the other three perfused groups. The external gross appearance of the UW-treated kidneys was normal, whereas that of the other groups demonstrated moderate to severe injury. Although the mean right/left renal weight difference of the UW-treated group was lower than that of the other three groups, this was not statistically significant. Under normothermic conditions in rats, UW solution affords significant renal protection from ischemia. Euro-Collins, normal saline, and Ringer's lactate solutions display no significant protective effect.Presented at the Twentieth Annual Meeting of the Peripheral Vascular Surgery Society, New Orleans, La., June 10, 1995.  相似文献   
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8.
BACKGROUND: Infarct border zone (IBZ) geometry likely affects inducibility and characteristics of postinfarction reentrant ventricular tachycardia, but the connection has not been established. OBJECTIVE: The purpose of this study was to determine characteristics of postinfarction ventricular tachycardia in the IBZ. METHODS: A geometric model describing the relationship between IBZ geometry and wavefront propagation in reentrant circuits was developed. Based on the formulation, slow conduction and block were expected to coincide with areas where IBZ thickness (T) is minimal and the local spatial gradient in thickness (DeltaT) is maximal, so that the degree of wavefront curvature rho proportional, variant DeltaT/T is maximal. Regions of fastest conduction velocity were predicted to coincide with areas of minimum DeltaT. In seven arrhythmogenic postinfarction canine heart experiments, tachycardia was induced by programmed stimulation, and activation maps were constructed from multichannel recordings. IBZ thickness was measured in excised hearts from histologic analysis or magnetic resonance imaging. Reentrant circuit properties were predicted from IBZ geometry and compared with ventricular activation maps after tachycardia induction. RESULTS: Mean IBZ thickness was 231 +/- 140 microm at the reentry isthmus and 1440 +/- 770 microm in the outer pathway (P <0.001). Mean curvature rho was 1.63 +/- 0.45 mm(-1) at functional block line locations, 0.71 +/- 0.18 mm(-1) at isthmus entrance-exit points, and 0.33 +/- 0.13 mm(-1) in the outer reentrant circuit pathway. The mean conduction velocity about the circuit during reentrant tachycardia was 0.32 +/- 0.04 mm/ms at entrance-exit points, 0.42 +/- 0.13 mm/ms for the entire outer pathway, and 0.64 +/- 0.16 mm/ms at outer pathway regions with minimum DeltaT. Model sensitivity and specificity to detect isthmus location was 75.0% and 97.2%. CONCLUSIONS: Reentrant circuit features as determined by activation mapping can be predicted on the basis of IBZ geometrical relationships.  相似文献   
9.
Background: Intravenous infusion of lidocaine decreases postoperative pain and speeds the return of bowel function. The authors therefore tested the hypothesis that perioperative lidocaine infusion facilitates acute rehabilitation protocol in patients undergoing laparoscopic colectomy.

Methods: Forty patients scheduled to undergo laparoscopic colectomy were randomly allocated to receive intravenous lidocaine (bolus injection of 1.5 mg/kg lidocaine at induction of anesthesia, then a continuous infusion of 2 mg [middle dot] kg-1 [middle dot] h-1 intraoperatively and 1.33 mg [middle dot] kg-1 [middle dot] h-1 for 24 h postoperatively) or an equal volume of saline. All patients received similar intensive postoperative rehabilitation. Postoperative pain scores, opioid consumption, and fatigue scores were measured. Times to first flatus, defecation, and hospital discharge were recorded. Postoperative endocrine (cortisol and catecholamines) and metabolic (leukocytes, C-reactive protein, and glucose) responses were measured for 48 h. Data (presented as median [25-75% interquartile range], lidocaine vs. saline groups) were analyzed using Mann-Whitney tests. P < 0.05 was considered statistically significant.

Results: Patient demographics were similar in the two groups. Times to first flatus (17 [11-24] vs. 28 [25-33] h; P < 0.001), defecation (28 [24-37] vs. 51 [41-70] h; P = 0.001), and hospital discharge (2 [2-3] vs. 3 [3-4] days; P = 0.001) were significantly shorter in patients who received lidocaine. Lidocaine significantly reduced opioid consumption (8 [5-18] vs. 22 [14-36] mg; P = 0.005) and postoperative pain and fatigue scores. In contrast, endocrine and metabolic responses were similar in the two groups.  相似文献   

10.
Sarcolectin (SCL) is a nonspecific stimulator of cellular DNA synthesis that was found in all animal sera tested to date. It inhibits the established interferon (IFN)-dependent antiviral state, restoring cells to their normal status. In this study, we examined the excretion/secretion of the IFN antagonist SCL in sera from healthy donors and in sera collected during different periods of human immunodeficiency virus type 1 (HIV-1) infection. We followed HIV-1-infected patients during all stages of development (seroconversion, initial and advanced phases of AIDS) and found a significant increase in SCL in sera of HIV-infected patients compared with seronegative subjects used as controls. This increase was established during seroconversion, and then the titers leveled off. In the final stage of the disease, the SCL titer increased again very significantly. We attribute this rapid rise to the virus-dependent destruction of T cells that can no longer be repaired. The high SCL level observed at this final stage, which is most predictive of the disease's progression, suggests that the action, rather than the production, of IFN is impaired.  相似文献   
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