Abnormal renal vasodilation to an amino acid infusion in congestive heart failure: normalization by enalapril

In congestive heart failure (CHF), the neurohormonal mechanisms that cause renal vasoconstriction, particularly those depending on the renin-angiotensin system, could interfere with renal vasodilating mechanisms. To elucidate this issue, we studied the kidney response to an amino acid infusion (known to cause renal vasodilation in healthy individuals) in eight patients with CHF. We found that the amino acid infusion (0.7 mL/kg/h of a 10% solution) elicited no renal hemodynamic response, in marked contrast to healthy subjects. We next hypothesized that the renin-angiotensin system (known to be activated in heart failure) has a role in the lack of response to the amino acid infusion. To test this hypothesis, we repeated the study after two 5-mg doses of enalapril, an inhibitor of the angiotensin-converting enzyme, administered 12 hours apart. After enalapril treatment, the amino acid infusion caused a 45% increase in mean renal blood flow (RBF) from 383 +/- 55 to 557 +/- 51 mL/min at the fifth hour (P < 0.05). This normalization of the renal response to the amino acid infusion occurred without changes in cardiac output or in systemic vascular resistance. Hence, the renal fraction of the cardiac output increased during the amino acid infusion. The recovery of the renal vascular response was not accompanied by an increase in glomerular filtration rate (GFR; filtration fraction decreased), suggesting a predominant efferent arteriole dilatation. Our study shows that, in heart failure, the kidney loses its ability to increase RBF in response to an amino acid load. This lack of renal vascular response can be restored by inhibiting the renin-angiotensin system and is unrelated to changes in systemic hemodynamics.     

La neurostimulation n’augmente pas le taux de succès du bloc du nerf saphène

PURPOSE: To evaluate neurostimulation of motor components of the vastus medialis muscle and the rectus femoris muscle, with a view to blocking the medial sensory fibres of the saphenous nerve. METHOD: First we dissected four femoral trigones, in order to select our puncture point. We were able to observe that, at the flexion crease of the thigh, the different fibers that make up the femoral nerve were clustered together and the saphenous nerve and the vastus medialis nerve had not yet separated from the femoral stem. Secondly, we conducted a prospective clinical study among 71 patients who had undergone surgery on the lower third of the leg with a sciatic block and a saphenous nerve block. The saphenous nerve block was performed using 10 mL of local anesthetic, by puncturing the flexion crease of the thigh in a bid to obtain one of two muscle responses: medial (contraction of the vastus medialis muscle) or anterior (contraction of the rectus femoris muscle and elevation of the patella). RESULTS: There was an overall success rate of 80% with the saphenous nerve block, with no statistical difference existing between the two response types. Average duration for the block to be completed was two minutes and it took an average of 15 min before the anesthesia took effect. No complications were encountered, apart from a puncture of the femoral artery, which was clinically inconsequential. CONCLUSION: Neurostimulation of the vastus medialis muscle has the same effect as neurostimulation of the rectus femoris muscle with respect to anesthesia of the saphenous nerve. Neurostimulation of the medial compartment of the femoral nerve saves local anesthetic, compared to a standard femoral block.     

假肿瘤性胰腺炎的CT表现

目的 提高对慢性假肿瘤性胰腺炎的影像学特征的认识,材料与方法 回顾性分析１２例经临床、病理诊断的假肿瘤性胰腺炎的特点,结果 １２例均见胰产质肿块形成,大多为类圆形,直径为２．５～４ｃｍ,边缘规则,肿块较均质,如肿块较大,则密度不均,中心坏死,边缘不规则,８例肿块内有钙化,ＣＴ增强扫描肿块大多呈明显强化,１１例位于胰头部,１例位于胰体部,７例Ｂ超呈低回声,５例为不均匀回声,结论 假肿瘤性胰腺炎与胰腺     

Postoperative analgesia after total hip arthroplasty: patient-controlled analgesia versus transdermal fentanyl patch

STUDY OBJECTIVE: To determine whether a new transdermal fentanyl patch (TFP) is a good choice for the postoperative pain management of patients undergoing primary total hip arthroplasty compared with patient-controlled analgesia (PCA). DESIGN: Randomized, prospective study. SETTING: University hospital. PATIENTS: 30 patients undergoing primary total hip arthroplasty. INTERVENTIONS: Patients received either a TFP (group T; Duragesic 50 microg/h, matrix fentanyl patch, Janssen-Cilag) applied approximately 10 hours before induction of general anesthesia and PCA programmed in the postanesthesia care unit (PACU), or PCA programmed in the PACU (group P). MEASUREMENTS: Intraoperative sufentanil and additional postoperative morphine administration were recorded, as well as visual analog scores and routine vital signs at predetermined intervals during the first 48 hours. MAIN RESULTS: Morphine consumption on arrival in the PACU was 3.5+/-3 mg in group T versus 13+/-5 mg in group P (P<0.0001). Visual analog scores on arrival in the PACU were 37+/-22 mm in group T versus 73+/-13 mm in group P (P<0.0001). Cumulative morphine consumption at the 24th hour was 43+/-16 mg in group P and 4+/-3 mg in group T (P<0.0001). Cumulative morphine consumption at the 48th hour was 54+/-26 mg in group P and 5+/-4 mg in group T (P<0.0001). Intraoperative sufentanil consumption was 38+/-15 microg in group T versus 30+/-5 microg in group P (not significant). The sedation score was 0 in both groups during the first 48 postoperative hours. CONCLUSIONS: Preoperative TFP application decreases pain scores and morphine consumption in the PACU and appears to have prolonged effects spanning the first 48 postoperative hours.