Blood flow acceleration in the carotid and brachial arteries of healthy volunteers: respective contributions of cardiac performance and local resistance

Summary— The influence of local resistance and cardiac performance on peripheral blood acceleration was investigated in 14 healthy male volunteers. Steady and pulsatile flow was studied in the brachial and in the common carotid arteries, ie, two territories that exhibit marked differences in resistive characteristics. Instantaneous blood velocity (V), mean blood velocity (V_m) and artery diameter (D) were evaluated at rest by an ultrasonic range-gated pulsed Doppler flowmeter using a double transducer probe, thus allowing the calculation of mean blood flow (Q). Mean local resistance (R) was obtained by dividing the mean arterial pressure by Q. The peak value of the local acceleration of the blood was obtained by computer-assisted calculation of the first derivative of instantaneous blood velocity (G_max = +dV/dt_max). Peak aortic blood acceleration (GAo) was simultaneously measured from the suprasternal notch using a pulsed Doppler velocity meter. In the brachial and the common carotid arteries, G_max was of a similar magnitude (551 ±30 and 555 ± 44 cm/s², respectively) despite major differences in the respective D, V_m, Q and R values. In neither artery was there a relationship between G_max and either resting Q or R. At the brachial artery level, G_max was positively related to GAo ( r = 0.79, P = 0.0008). At the common carotid artery level, there was a weak, although non significant relationship between G_max and GAo ( P = 0.08). Our results indicate that the local acceleration of peripheral blood flow in the brachial artery is related rather to upstream central impulse than to downstream hemodynamics, and suggest some regional differences in the hemodynamic determinants of the local acceleration of peripheral blood flow.     

Iotrol versus metrizamide in lumbar myelography: a double-blind study

In a prospective, randomized, double-blind study, 49 patients underwent lumbar myelography using iotrol (24 patients) or metrizamide (25 patients). The diagnostic imaging adequacy of iotrol was comparable with that of metrizamide. After iotrol myelography, adverse reactions were fewer, less severe, and of shorter duration than were those following metrizamide myelography. Thirteen of 24 patients (54%) receiving iotrol reported some adverse reactions compared with 24 of 25 patients (96%) receiving metrizamide. Five moderate and one severe adverse reaction occurred in the group receiving iotrol. Fourteen moderate and eight severe adverse reactions occurred in the group receiving metrizamide. Thirty-eight patients underwent electroencephalography both before and after myelography (19 iotrol and 19 metrizamide). None of the EEGs obtained after iotrol myelography changed from baseline, while seven of the EEGs obtained after metrizamide myelography showed changes from baseline. Iotrol was judged superior to metrizamide as a contrast medium in this patient population.     

Prevention of deep vein thrombosis after elective hip surgery. A randomized trial comparing low molecular weight heparin with standard unfractionated heparin.

OBJECTIVE: To determine the relative efficacy and safety of low molecular weight (LMW) heparin (Enoxaparin) compared with standard calcium heparin for the prevention of postoperative deep vein thrombosis in patients undergoing elective hip surgery. DESIGN: A double-blind, randomized, controlled trial. PATIENTS: Six hundred sixty-five consecutive patients undergoing hip replacement at five participating hospitals. INTERVENTIONS: Patients received either fixed-dose LMW heparin, 30 mg subcutaneously twice daily, or fixed-dose standard calcium heparin, 7500 units subcutaneously twice daily; both regimens were started 12 to 24 hours after surgery and continued for 14 days or until discharge if sooner. MEASUREMENTS: All patients had postoperative I-125-fibrinogen leg scanning and impedance plethysmography. If results of one or both tests were positive, then venography was done. Otherwise, venography was done between day 10 and day 14, or sooner if the patient was ready for discharge. RESULTS: Evaluable venograms were obtained in 258 of the 333 patients randomly assigned to receive LMW heparin and in 263 of the 332 patients assigned to receive calcium heparin. For patients with evaluable venograms, thrombosis was detected in 50 patients (19.4%) who received LMW heparin compared with 61 patients (23.2%) who received standard heparin (difference, -3.8%; 95% CI, -11.1% to 3.6%) (P greater than 0.2). Proximal deep vein thrombosis was detected in 5.4% of the patients receiving LMW heparin and in 6.5% of the patients receiving standard heparin (difference, -1.1%; CI, - 5.2% to 3.3%) (P greater than 0.2). For the entire group of 665 patients, venous thrombosis occurred in 17.1% given LMW heparin and in 19.0% given standard heparin. Hemorrhagic complications occurred in 31 patients (9.3%) given standard heparin and in 17 patients (5.1%) given LMW heparin (difference, 4.2%; CI, 0.3% to 8.2%) (P = 0.035). The relative risk reduction was 45%. The rate of major bleeding in the standard heparin group was 5.7% compared with 3.3% in the LMW heparin group (difference, 2.4%; CI, -1.0% to 5.4%) (P = 0.13). The relative risk reduction was 42%. CONCLUSION: Low molecular weight heparin is significantly less hemorrhagic than standard unfractionated heparin; the difference in the rate of deep vein thrombosis, although not statistically significant (P greater than 0.2), favors the use of LMW heparin.     

Chromogalactography preceding ductal-lobular unit excision for nipple discharge--with special reference to diagnostic galactography and histology

Between 1981-88, 223 surgical interventions were performed in cases of pathologic breast secretion after exclusion of extra-mammary aetiology. The milk duct was identified by pre-operative chromogalactography, followed by a selective excision of the ductal-lobular unit. In 36 cases (16.1%), however, neither spontaneous nor provocable secretion remained after diagnostic galactography, so that a segment resection was required. In all tissue specimens, the cause of the pathologic secretion was found histologically; most often, it was fibrocystic disease or solitary intraductal papilloma (21.5% each). In 32.3% of the specimens, findings with a prospective significance (papillomatosis, carcinoma in situ or invasive carcinoma) were discovered and further operative treatment was initiated. The colour of the discharge allowed no prediction of the histological findings. In 28.6% (8/28) of the carcinomas, secretion was bilateral. In 46.4% of the specimens containing carcinoma, papillomatosis was also detected; vice versa, papillomatosis was associated with carcinoma in 22.8%. The recurrence rate of 1.6% indicates the efficiency of this method in removing the pathology. The diagnostic value of galactography for the prediction of findings with a prospective significance was considerably reduced by a rate of 37.5% false-negatives; therefore, we have decided to omit diagnostic galactography in our patients. Now, provided extra-mammary causes of the nipple discharge have been excluded and mammography has been inconspicuous, a selective excision of the ductal-lobular unit is performed after preoperative chromogalactography.     

Role for interleukin-1 (IL-1) in benzene-induced hematotoxicity: inhibition of conversion of pre-IL-1 alpha to mature cytokine in murine macrophages by hydroquinone and prevention of benzene-induced hematotoxicity in mice by IL-1 alpha

Chronic exposure of humans to benzene (BZ), a myelotoxin, causes aplastic anemia and acute leukemia. The stromal macrophage that produces interleukin-1 (IL-1), a cytokine essential for hematopoiesis, is a target of BZ's toxicity. Monocyte dysfunction and decreased IL-1 production have been shown to be involved in aplastic anemia in humans. Hydroquinone (HQ), a toxic bone marrow (BM) metabolite of BZ, causes time- and concentration-dependent inhibition of processing of the 34-Kd pre-interleukin-1 alpha (IL-1 alpha) to the 17-Kd mature cytokine in murine P388D1 macrophages and BM stromal macrophages, as measured by Western immunoblots of cell lysate proteins using a polyclonal rabbit antimurine IL-1 alpha antibody. HQ over a 10-fold concentration range had no effect on the lipopolysaccharide (LPS)-induced production of pre- IL-1 alpha precursor or on cell viability or DNA and protein synthesis. Stromal macrophages obtained from the femoral BM of C57Bl/6 mice exposed to BZ (600 or 800 mg/kg body weight) for 2 days were incapable of processing the 34-Kd pre-IL-1 alpha to the mature 17-Kd cytokine when stimulated in culture with LPS. Stromal macrophages from mice coadministered BZ and indomethacin, a prostaglandin H synthase (PHS) inhibitor that has been shown to prevent BZ-induced myelotoxic and genotoxic effects in mice when coadministered with benzene were able to convert the pre-IL-1 alpha to mature cytokine. Administration of recombinant murine IL-1 alpha (rMuIL-1 alpha) to mice before a dose of BZ that causes severe depression of BM cellularity completely prevents BM depression, most probably by bypassing the inability of the stromal macrophage in BZ-treated animals to process pre-IL-1 alpha to the mature cytokine.     

Acute peripheral arterial and graft occlusion: treatment with selective infusion of urokinase and lysyl plasminogen

Thirty-five patients hospitalized for recent angiographically documented arterial occlusion in the legs (27 femoropopliteal arteries and eight grafts) benefited from local fibrinolytic therapy delivered at the site of the occlusion with a 4- or 5-F catheter. This therapy combined a continuous urokinase (UK) infusion of 1,000 U/kg/hour and a lysyl plasminogen (LYS-PLG) infusion of 15 microkatals every 30 minutes. Angiographically confirmed lysis was obtained in 85% of the cases. Only 3% of the patients had major and 6% had minor groin hematomas. Only two patients had concentrations of fibrinogen as low as 100 mg/dl. Intravascular infusion of UK-LYS-PLG is as effective as streptokinase. Its excellent tolerance makes it a good alternative in the treatment of acute ischemia in the lower limbs.     

Hepatic artery injection of I-131-labeled lipiodol. Part I. Biodistribution study results in patients with hepatocellular carcinoma and liver metastases

Biodistribution of iodine-131-labeled Lipiodol Ultra-Fluide (I-131 LUF) injected into the hepatic artery was studied scintigraphically in 47 patients with hepatocellular carcinoma (n = 23), hepatic metastases (n = 14), or normal livers (n = 10). The investigation was extremely well tolerated. I-131 LUF concentrated mainly in the liver (L) and the lungs (l), with L/L + l activity ratios greater than 75% for all three groups of patients. I-131 LUF distribution was homogeneous in normal livers and heterogeneous in cirrhotic livers. I-131 LUF concentrated in the tumor with a tumorous (T) to nontumorous (NT) activity ratio (T/NT) of 4.3 +/- 3.6 for hepatocellular carcinoma and 2.4 +/- 0.7 for hepatic metastases. The effective half-life of I-131 LUF is more than 4.5 days for the three groups. It was eliminated mainly through the urine. Clearance from tumor is slower than from normal liver, as shown by the increase in T/NT at day 18. Biodistribution did not change in patients who had a second injection, which indicates that there is no saturation phenomenon. The results of this study suggest that LUF may be considered as a potential carrier vehicle for therapeutic agents.