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901.
Background: The effects of inhalational anesthetics on the microcirculation, including leukocyte dynamics, remain to be clarified. The authors investigated halothane and sevoflurane anesthesia to determine if these agents evoked leukocyte adhesion through endothelial cell-dependent mechanisms involving such adhesion molecules.

Methods: Rats were anesthetized with halothane or sevoflurane in 100% oxygen and the lungs were mechanically ventilated. Leukocyte behavior in mesenteric venules was recorded through intravital video microscopy under monitoring microvascular hemodynamics. To examine the mechanisms for leukocyte rolling and adhesion, these studies were repeated after animals were pretreated with a monoclonal antibody against P-selectin (MAb PB1.3) or against intracellular adhesion molecule-1 (ICAM-1; MAb 1A29): P-selectin required for rolling of circulating leukocytes and ICAM-1 for firm adhesive interactions with leukocyte integrins.

Results: Under baseline anesthetic conditions (1 minimum alveolar concentration [MAC]), venular wall shear rates, an index of the disperse force on marginating leukocytes, in the sevoflurane-treated rats were about two times higher than those with halothane. At 2 MAC, halothane caused a marked arteriolar constriction and decreasing shear rates concurrent with an increasing density of venular leukocyte adhesion. Sevoflurane at 2 MAC induced leukocyte rolling and adhesion, which were attenuated by PB1.3 and 1A29, without alterations in the wall shear rates. Halothane-induced leukocyte adhesion was not prevented by PB1.3 but it was by 1A29.  相似文献   

902.
Cerebral Emboli during Cardiac Surgery in Children   总被引:7,自引:0,他引:7  
Background: Microemboli occur commonly during cardiac surgery in adults, and, when present, increase the risk of neuropsychological deficits. Their incidence and significance during correction of congenital heart disease is unknown. The authors hypothesized that microemboli would occur before bypass with right-to-left cardiac shunts and would also occur in large numbers when the aortic crossclamp was released in children during repair of congenital heart defects.

Methods: In 25 children studied with carotid artery Doppler, embolic signals were counted and timed in relation to 13 intraoperative events. Patients were classified as either at high risk (obligate right-to-left shunt or uncorrected transposition of the great arteries) or at low risk (net left-to-right shunt or simple obstructive lesions) for paradoxical (venous to arterial) emboli.

Results: The median number of emboli detected was 122 (range, 2-2,664). Forty-two percent of all emboli were detected within 3 min of release of the aortic crossclamp. The high-risk group had significantly more emboli (median, 66; range, 0-116) during the time interval before cardiopulmonary bypass than did the low-risk group (median, 8; range, 0-73), with P < 0.01. There was no significant difference between the high-and low-risk groups in the total number of emboli detected. There was no apparent association between number of emboli and gross neurologic deficits.  相似文献   

903.
Study Objective: To test the hypothesis that slow administration of local anesthetic into the epidural space by gravity flow reduces the incidence of signs and symptoms of unintended injection.

Design: Prospective, randomized study.

Setting: Teaching hospital.

Patients: 600 ASA physical status I and II parturients scheduled for labor and delivery or elective cesarean section.

Interventions: After identification of the epidural space with pulsations of an air-fluid column, parturients for vaginal delivery (n = 380) were randomized to receive a test dose of 3 ml 3% 2-chloroprocaine with epinephrine 20 μg, two doses of 7 ml bupivacaine 0.03 % with sufentanil 1 μg/ml and epinephrine 2 μg/ml by either gravity flow (Group 1) given over 30 seconds or by bolus injection (Group 2) given over 5 seconds through the epidural needle; parturients for Cesarean delivery (n = 220) were randomized to receive a test dose and two doses of 6 ml lidocaine 2 % with sufentanil 1 μg/ml and epinephrine 2 μg/ml by either gravity flow or by bolus injection through the epidural needle. Changes in maternal heart rate (HR) and blood pressure, signs of intravascular injection, and adverse effects of epidural bupivacaine-sufentanil were recorded after each dose.

Measurements and Main Results: Gravity flow administration (Group 1) was associated with a smaller increase in mean maternal HR (p < 0.001), less hypotension (p < 0.01), sedation (p < 0.01), nausea (p = 0.01), and segmental spread (p < 0.0001) than were corresponding doses given by traditional bolus injection (Group 1) for vaginal or Cesarean deliveries. The incidence of systemic toxicity was zero of 300 (0%) with gravity flow and 4 of 300 (1.3%) by bolus injection, p = 0.12, Fisher's exact test. No patient in either group had an accidental intrathecal injection.

Conclusion: Gravity flow administration of local anesthetic-opioid solution during epidural block for obstetrics was associated with fewer signs of systemic drug absorption and cardiovascular perturbations than was the traditional bolus injection. This study supports the current opinion that slow administration of local anesthetic during epidural black contributes to fewer adverse events.  相似文献   

904.
905.
906.
It is often difficult to make a clinical or histologic diagnosis of erythrodermic mycosis fungoides (MF) and Sézary syndrome (SS). Whereas the histologic parameters for making a diagnosis of MF with well-developed patch and plaque stage lesions are clearly defined, the same criteria appear to be less relevant for diagnosing MF in patients with erythroderma secondary to the disease. In order to better define the histologic features of erythrodermic MF and SS, we studied 28 routine histologic sections of 17 patients with known erythrodermic MF or SS. Sections were reviewed independently by 2 dermatopathologists. Each of 24 parameters was scored semi-quantitatively and the data were compared to data previously reported from a group of 64 patients with limited patch and plaque stage lesions of MF. When compared to biopsies from patients with limited patch/plaque lesions, biopsies taken from erythrodermic patients displayed more parakeratosis (p=0.0492) and acanthosis (p=0.0046), less disproportionate epidermotropism, fewer lymphocytes aligned within the basal layer (p=0.0045), fewer hyper-convoluted cells in the epidermis, more dermal hyperconvoluted cells (p=0.0191), more papillary dermal fibrosis (p=0.0002), more prominent teleangiectasias (p=0.0028) and more mitotic figures.
The histologic features of erythrodermic MF and Sézary syndrome are even more subtle than the features of patch and plaque stage MF, thus rendering the histologic diagnosis more difficult.  相似文献   
907.
Early Stroke Recognition: Developing an Out-of-hospital NIH Stroke Scale   总被引:1,自引:0,他引:1  
Objective : To develop an abbreviated and practical neurologic scale that could assist emergency medical services or triage personnel in identifying patients with stroke.
Methods : A prospective, observational, cohort study was performed at university-based EDs. Participants were 74 patients treated in a thrombolytic stroke trial and 225 consecutive non-stroke patients evaluated during 4 random 12-hour shifts in the ED. Scores on the NIH Stroke Scale were obtained for all patients by physicians. Items of this scale were modified and recoded to a binomial (normal or abnormal) scale. Serial univariate analyses using χ2 were performed to rank items. Recursive partitioning was then performed to develop the decision rule for predicting the presence of stroke.
Results : Three items identified 100% of patients with stroke: facial palsy, motor arm, and dysarthria. An Abbreviated NIH Stroke Scale based on these items had a sensitivity of 100% and a specificity of 92%. A proposed Out-of-hospital NIH Stroke Scale consisting of facial palsy, motor arm, and a combination of dysarthria and best language items (abnormal speech) had a sensitivity of 100% and a specificity of 88%.
Conclusion : Using the derivation data set, a proposed Out-of-hospital NIH Stroke Scale had a high sensitivity and specificity for identifying patients with stroke when performed by physicians in this group of 299 ED patients. Prospective studies of other health care professionals using the scale in the out-of-hospital arena are needed.  相似文献   
908.
Background In patients with vitiligo, sometimes the greatest part of the skin has already lost its melanocytes. The remaining pigmented patches can be removed by using strong bleaching creams, but many adverse events have been reported with this treatment. Anew depigmentation therapy could be treatment with a Ruby laser. Methods Before treatment, the patients filled out a questionnaire about their vitiligo history. Eight patients with remaining pigmentation of the arms, hands, and face were treated once with a Ruby laser. Patients were monitored for developing repigmentation during the 9 months after treatment. Results In patients with a positive Koebner phenomenon, a permanent state of depigmentation was reached after laser therapy. None of the treated patients showed severe side-effects. Conclusions Ruby laser treatment can be an effective, fast, and safe method for removing cosmetically disturbing remnants of normal pigmentation in vitiligo patients with a positive Koebner phenomenon.  相似文献   
909.
SUMMARY Impotence is a common symptom which can cause considerable distress to both the sufferer and his partner. The use of pharmacotherapy to improve erectile function will continue to increase as safe and effective drugs are developed. However, restoring erectile function should not be the only treatment objective. It is also essential to address personal and emotional factors in the sufferer, conflicts in his relationship with his partner, and sexual problems in his partner, all of which may be instrumental in causing or maintaining the presenting impotence. We advocate a combined approach with appropriate medical treatment and sex and couple therapy  相似文献   
910.
Background: Small doses of bupivacaine may be a reasonable choice for spinal anesthesia for patients having ambulatory surgery. However, few dose-response data are available to guide the selection of reasonable doses of bupivacaine for different ambulatory procedures.

Methods: Eight volunteers per group were randomized to receive 3.75, 7.5, or 11.25 mg of 0.75% bupivacaine with 8.25% dextrose in a double-blind manner. Sensory block was assessed with pinprick, transcutaneous electrical stimulation equivalent to surgical incision at the ankle, knee, pubis, and umbilicus, and with duration of tolerance to pneumatic thigh tourniquet. Motor block at the quadriceps and gastrocnemius muscles was assessed with isometric force dynamometry. Times until recovery from spinal anesthesia were recorded. Dose-response relationships were determined by linear regressions. Mean (95% confidence intervals) for durations of sensory and motor block per milligram of bupivacaine administered were calculated from linear regressions.

Results: Significant dose-response relationships (P < 0.006) were determined for sensory block, motor block, and time until recovery (R from 0.6 to 0.9). Within the range of doses studied, each additional milligram of bupivacaine was associated with an increase in duration of tolerance to transcutaneous electrical stimulation of 10 (7 to 13) min, an increase in tolerance to tourniquet of 7 (2 to 11) min, an increase in duration of motor block of 8 (5 to 12) min, and an increase in time until recovery of 21 (17 to 25) min.  相似文献   

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