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101.
Study Objective: To describe the hemodynamic consequences of a regional chemotherapy procedure involving occlusion of the thoracic aorta and inferior vena cava (IVC) by intraluminal balloons.

Design: Prospective study.

Setting: Operating rooms of an academic hospital.

Patients: 10 patients with inoperable intraabdominal malignancy.

Interventions: After the induction of general anesthesia and the insertion of a pulmonary artery catheter the patients underwent the regional chemotherapy procedure

Measurements and Main Results: Occlusion of the thoracic aorta induced an increase in blood pressure (BP) and systemic vascular resistance (SVR) (41% ± 8% and 80% ± 15% from baseline, respectively), and a 30% ± 7% decrease in cardiac output (CO). After aortic balloon deflation at the end of the procedure, we observed a decrease in BP to baseline values, decrease in SVR (to 62% ± 12% below baseline), and increase in CO (to 80% ± 15% above baseline). Those changes resemble those described during vascular surgery. Isolated occlusion of the IVC before aortic occlusion caused hemodynamic deterioration in only three of 10 patients, suggesting incomplete obstruction or collateral blood flow in others. Occluding the IVC while the aorta was occluded, caused minimal hemodynamic changes.

Conclusions: Independent inflation of the IVC balloon should not be performed routinely because of possible unpredicted hemodynamic instability. Inferior vena cava occlusion should always be performed after complete aortic occlusion, because it is then that it produces negligible hemodynamic consequences. It is possible that a better assessment of IVC occlusion after balloon inflation needs to be done by contrast injection to prevent a possible leak of chemotherapeutic drugs.  相似文献   

102.
Physiological concepts and experimental evidence indicate the feasibility of developing an effective artificial visual system through direct stimulation of the visual cortex. The technical, medical and physiological aspects are reviewed.  相似文献   
103.
Two cases of envenoming by Cerastes vipera are described Both were in snake collectors who were accidentally bitten on the finger while handling the snake. In both cases, local signs included a haemorrhagic bulla with fang marks, swelling and tenderness. These signs were mild in one case and moderately severe in the other, necessitating fasciotomy. No systemic signs were observed. Some coagulation abnormalities were found in both cases. In one, prolonged bleeding from the wound and a shortened euglobulin lysis time may suggest activation of the fibrinolytic mechanism. In the other, prolongation of prothrombin time occurred with no haemorrhagic diathesis. Treatment included fasciotomy in one case and elevation of the affected part and antibiotics in the other. It appears that the clinical course of this snakebite is relatively benign.  相似文献   
104.
105.
Capecitabine can interact with warfarin, resulting in altered coagulation parameters and bleeding. Four cases have been reported. We describe a fifth case with life-threatening interaction between these two drugs. A 67-year-old female with metastatic breast cancer developed hemorrhagic blisters, purpura and ecchymoses. She had been well controlled on long-term warfarin (5 mg/day). Capecitabine was initiated 4.5 weeks prior to the bleeding episode. Laboratory work-up revealed an international normalized ratio of 8.56, partial prothrombin time of 61 seconds and prothrombin time of 5.2%. The coagulation parameters gradually normalized within 4 days following vitamin K administration and discontinuation of capecitabine and warfarin. Careful monitoring of coagulation parameters and proper adjustment of the warfarin dose are required in patients taking warfarin and capecitabine concomitantly.  相似文献   
106.
A 63-year-old man was diagnosed with metastatic MCC. Preliminary staging PET scan with 18F-FDG was not done at the time of diagnosis. After completion of chemo- and radiotherapy, the patient underwent a CT scan of the area from the maxilla to the ischium; no evidence of disease was noted. Clinically, the patient was considered to be in remission. The CT scan was followed by head-to-toe FDG-PET scanning which revealed foci of metastatic disease in the right mid- thigh and left proximal calf. This case demonstrates the added value of head-to-toe FDG-PET for the detection of distant metastases in MCC.  相似文献   
107.
We report a case of an elbow arthrodesis using a modular hinged external fixation device in a patient who sustained a complex high-energy injury. The extensive bone and soft-tissue loss and local infection precluded restoration of the articular anatomy. Other reconstructive options, including total elbow arthroplasty and allograft reconstruction, were not appropriate in this clinical situation. A transelbow hinged external fixator was applied with the elbow in extension. Subsequently, the hinge was brought gradually into 90 degrees of flexion as the elbow fused. Fixation and arthrodesis were successfully achieved by using this modular device, despite severe tissue loss and local septic complications. Furthermore, by gradually flexing the frame from full extension to 90 degrees , the need for flap coverage of the open wound was avoided.  相似文献   
108.
PURPOSE: We evaluated the efficacy of testosterone gel (T-gel) alone and in combination with sildenafil in hypogonadal patients with erectile dysfunction (ED). MATERIALS AND METHODS: A total of 49 hypogonadal men (mean age 60.7 years) with ED participated for a mean of 20.2 months. Blood was tested for total and bioavailable testosterone, and prostate specific antigen. Sexual function was assessed using the International Index of Erectile Function questionnaire and a global assessment question (GAQ). Men received 1% 5 gm T-gel for 6 months, and 100 mg sildenafil was added to those with a "no" response to the GAQ after 3 months on testosterone supplement. RESULTS: A total of 31 patients reported significant improvement in the sexual desire domain (from a mean +/- SD of 4.2 +/- 0.8 to 8.6 +/- 0.4) and erectile function (EF) domain (from 13.6 +/- 1.9 to 27 +/- 0.8) following treatment with testosterone supplement alone. One patient was excluded from study after urinary retention developed and 9 reported irritation at the gel application site. In spite of normalization of total and bioavailable testosterone values, and significant improvement of sexual desire domain scores, the EF of 17 men remained less than 26 or they responded "no" to the GAQ. These men received combined T-gel and sildenafil, after which all graded EF greater than 26 and responded positively to the GAQ. CONCLUSIONS: Combined treatment with sildenafil and T-gel has a beneficial effect on ED in hypogonadal patients in whom treatment with testosterone supplement alone failed.  相似文献   
109.
110.
Brainstem auditory evoked potentials (BAEPs) were recorded in 51 patients with different degrees of certainty with respect to multiple sclerosis (MS): Definite, probable and possible ( McAlpine et al. 1972). Click stimuli were presented at various intensities and rates which were thought to stress the auditory pathways. The main types of abnormal BAEP traces were the absence of some of the brainstem waves (in the presence of a normal audiogram), prolonged brainstem transmission time (BTT) and abnormal amplitude ratio. In the definite MS group, average BTT was prolonged and average amplitude ratio was more than two standard deviations greater than the corresponding parameter in the normal group. The stressful manoeuvres of increasing click repetition rate and lowering click intensity increased the degree of abnormality of BAEP traces. There was no case in which the response to standard click stimuli (75 dB HL, 10 or 20 per sec) showed a normal trace while increasing the stimulus repetition rate and/or decreasing intensity showed a pathological response. The pathophysiology of BAEP traces in MS is discussed.  相似文献   
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