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PubMed1995

Raised leg exercises for leg edema in the elderly.

UNLABELLED: Leg edema is a common problem in the elderly and requires further evaluation and management. METHOD: From October 1990 to July 1992, 245 patients presented to the Cleveland Clinic Florida with leg edema. All patients were counseled about the benefits of twenty-minute, three-times-a-day raised-leg exercises. Fifty seven (57) of the 245 patients were not compliant with this regimen (nonexercise group). Although not true controls, they formed a comparison group for those who performed the exercise regimen. The exercise group was composed of 188 patients with a mean age of 73 +/- 6.8 years, 25 (13%) men and 163 (87%) women; the nonexercise group was composed of 57 patients with a mean age of 71.9 +/- 4.3, 19 (33%) men and 38 (67%) women. Workup for leg edema included: comprehensive history, clinical examination including prostate or pelvic examination, complete blood count, chemistry profile, thyroid profile, electrocardiogram, chest radiograph, and, when indicated, pelvic or leg ultrasound and pelvic computed tomographic scan. The circumference of the leg with the maximum amount of edema was measured initially and on the fourth week. RESULTS: In this study, the common causes of leg edema in the elderly population were venous stasis (63.2%), drug induced (13.8%), and heart failure (15.1%). Postphlebitic syndrome, cirrhosis, lymphedema, lipedema, prostate carcinoma (CA), and ovarian mass were the less frequent findings. Upon comparison of the circumference of leg edema on initial visit and four weeks after, both the exercise and nonexercise groups showed significant decreases in the measurement of the leg edema (P < .001) except those caused by lymphedema.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1994

Effects of myofascial release leg pull and sagittal plane isometric contract-relax techniques on passive straight-leg raise angle.

Experimental evidence does not currently exist to support the claims of clinical effectiveness for myofascial release techniques. This presents an obvious need to document the effects of myofascial release. The purpose of this study was to compare the effects of two techniques, sagittal plane isometric contract-relax and myofascial release leg pull for increasing hip flexion range of motion (ROM) as measured by the angle of passive straight-leg raise. Seventy-five nondisabled, female subjects 18-29 years of age were randomly assigned to contract-relax, leg pull, or control groups. Pretest hip flexion ROM was measured for each subject's right hip with a passive straight-leg raise test using a fluid-filled goniometer. Subjects in the treatment groups received either contract-relax or leg pull treatment applied to the right lower extremity; subjects in the control group remained supine quietly for 5 minutes. Following treatment, posttest straight-leg raise measurements were performed. A one-way analysis of variance followed by a Newman-Keuls post hoc comparison of mean gain scores showed that subjects receiving contract-relax treatment increased their ROM significantly more than those who received leg pull treatment, and the increase in ROM of subjects in both treatment groups was significantly higher than those of the control group. The results suggest that while both contract-relax and leg pull techniques can significantly increase hip flexion ROM in normal subjects, contract-relax treatment may be more effective and efficient than leg pull treatment.

Adolescent↗
PubMed2002

Intramuscular and blood pressures in legs positioned in the hemilithotomy position : clarification of risk factors for well-leg acute compartment syndrome.

BACKGROUND: Acute compartment syndrome has been widely reported in legs positioned in the lithotomy position for prolonged general surgical, urologic, and gynecologic procedures. The orthopaedic literature also contains reports of this complication in legs positioned on a fracture table in the hemilithotomy position. The purpose of this study was to identify the risk factors for development of acute compartment syndrome resulting from this type of leg positioning. METHODS: Eight healthy volunteers were positioned on a fracture table. Intramuscular pressures were continuously measured with a slit catheter in all four compartments of the left leg with the subject supine, in the hemilithotomy position with the calf supported, and in the hemilithotomy position with the heel supported but the calf free. Blood pressure was measured intermittently with use of automated pressure cuffs. RESULTS: Changing from the supine to the calf-supported position significantly increased the intramuscular pressure in the anterior compartment (from 11.6 to 19.4 mm Hg) and in the lateral compartment (from 13.0 to 25.8 mm Hg). Changing from the calf-supported to the heel-supported position significantly decreased intramuscular pressure in the anterior, lateral, and posterior compartments (to 2.8, 3.4, and 1.9 mm Hg, respectively). The mean diastolic blood pressure in the ankle averaged 63.9 mm Hg in the supine position, which significantly decreased to 34.6 mm Hg in the calf-supported position. Changing to the heel-supported position had no significant effect on the diastolic blood pressure in the ankle (mean, 32.8 mm Hg). The mean difference between intramuscular pressure and diastolic blood pressure in the supine position was approximately 50 mm Hg in each of the four compartments. This mean difference significantly decreased to <20 mm Hg in the calf-supported position and then, when the leg was moved into the heel-supported position, significantly increased to approximately 30 mm Hg in all compartments. CONCLUSIONS: The combination of increased intramuscular pressure due to external compression from the calf support and decreased perfusion pressure due to the elevated position causes a significant decrease in the difference between the diastolic blood pressure and the intramuscular pressure when the leg is placed in the hemilithotomy position in a well-leg holder on a fracture table. Combined with a prolonged surgical time, this position may cause an acute compartment syndrome of the well leg. Leaving the calf free, instead of using a standard well-leg holder, increases the difference between the diastolic blood pressure and the intramuscular pressure and may decrease the risk of acute compartment syndrome.

Adult↗
PubMed1987

Effects of leg press training on cycling, leg press, and running peak cardiorespiratory measures.

Six males and seven females trained 3 d per wk (30 min at 80 to 85% heart rate reserve) for 20 wk on a leg press apparatus. A progressive exercise test was administered on a cycle ergometer, leg press apparatus, and treadmill before and after training. Before training, peak oxygen consumption (VO2, ml X kg-1 X min-1) during the leg press test was higher for the males (23.9 +/- 1.60, mean +/- SE) compared to the females (19.5 +/- 2.40, P less than or equal to 0.05). Peak VO2 during the cycling (males = 36.6 +/- 2.65, females = 28.5 +/- 2.35) and treadmill (males = 39.8 +/- 2.04, females = 33.2 +/- 2.64) tests was also different between the sexes, and 30 to 40% higher than during the leg press test (P less than or equal to 0.05). Peak heart rate (beats X min-1) was not different between the sexes (P greater than 0.05), yet was 11% lower during the leg press test (165 +/- 3.5) compared to the cycling (184 +/- 2.8) and treadmill (187 +/- 1.3) tests (P less than or equal to 0.05). After training, peak VO2 during the cycling and treadmill tests increased 10 to 15%, compared to 35% during the leg press test (P less than or equal to 0.05). The only change in peak heart rate was a 6% increase during the leg press test (P less than or equal to 0.05). Although peak VO2 on the leg press apparatus was lower than on the cycle ergometer and treadmill, leg press exercise elicited a sufficient stimulus for increasing peak VO2 on the three testing modes.

Adult↗
PubMed1998

[99mTc-tetrofosmin exercise leg perfusion scintigraphy in arteriosclerosis obliterans (ASO)--assessment of leg ischemia using two phase data acquisition].

Twenty-one patients with arteriosclerosis obliterans (ASO) were studied with 99mTc-tetrofosmin exercise leg perfusion scintigraphy using the delayed administration method. In this method, tracer was injected 4 minutes after termination of symptom-limited repetitive climbing of a stair to validate prolonged vasodilatation in an ischemic lower limb after exercise. Visual and quantitative analyses were performed to evaluate a diseased leg using dynamic and static images. On a posterior whole body image, all cases except one showed decreased foot uptake in the affected side (affected normal ratio; ANR = 0.82 +/- 0.14). On dynamic images, 9 cases showed transient hyper-accumulation (blush phenomenon) only in the thigh of the affected side suggesting that this valuable finding may be a useful diagnostic sign to distinguish a diseased leg. Sensitivity and positive predictive value were 71.4% and 93.8% to detect a diseased leg based on more than one finding of non-visualization of ilio-femoral artery, muscle-soft tissue blush, and early venous return in a dynamic study. Moreover, a low uptake of ANR of below 0.90 in the foot in the static study gave an improved sensitivity of 85.7%. The transit time of the diseased legs (12.0 +/- 3.1 sec.) which was determined as the interval between the time of arterial and venous peak counts was significantly shorter than that of normal legs (17.3 +/- 4.5 sec.; p < 0.0001, paired t-test). The cases with blush phenomenon showed significantly higher thigh ANR (1.04 +/- 0.11) than those without (0.94 +/- 0.08; p < 0.05, unpaired t-test). These results could reflect prolongation of a hypervascular state after exercise in a diseased leg which sometimes induced blush phenomenon at arterial phase and high leg uptake at static phase. This scintigraphy is useful for the detection of a diseased leg as well as for grasping changes of vascular regulation after stress in patients with ASO.

Aged↗
PubMed1998

Venoarteriolar response to experimental venous hypertension in legs with chronic venous insufficiency and in healthy legs, measured using a double-wavelength laser Doppler technique.

The venoarteriolar response (VAR) of the skin in legs caused by experimental venous hypertension was measured using a new, double-wavelength laser Doppler probe technique (543 nm and 780 nm). This enables the measurement of the laser Doppler flux in the superficial and deep layers of the skin simultaneously. The recordings were obtained from the leg with the patient in a recumbent position with a sphygmomanometer cuff around the thigh. The VAR was recorded at the cuff pressures of 30 mmHg and 60 mmHg. Ten patients with chronic venous insufficiency (CVI) and 20 control subjects with healthy legs were investigated. The VAR increased in relation to the increase of cuff pressure at both wavelengths. There were no significant differences in the VAR between the cuff pressures within or between the legs with CVI and healthy legs. The VAR measured at 780 nm was very significantly greater than the VAR measured at 543 nm in legs with CVI (p<0.005), as well as in healthy legs (p<0.001). The VAR depends both on the wavelength of the laser Doppler light used and on the degree of venous hypertension. The VAR is not impaired in legs with CVI compared with healthy legs.

Adult↗
PubMed1991

Perturbation of the motor system in freely walking cockroaches. II. The timing of motor activity in leg muscles after amputation of a middle leg.

1. The effects of amputation of a middle leg on the motor pattern in the legs of freely walking cockroaches (Periplaneta americana L.) were studied. 2. The general effects of amputating a middle leg are similar to those arising from amputation of a rear leg. These effects are: multiple bursting, more variable and inconsistent timing (phase) between bursts and a tendency for timing effects to appear only during relatively slow walking. 3. The phase of bursts in the amputated stump relative to bursts in the leg in front of it was speed-dependent. However, the phase of stump bursts relative to bursts in the legs across from and behind the stump were not especially dependent on the speed of walking. In general, the phases of bursts in most leg pairs seemed relatively little affected by the amputation except for an increase in scatter. 4. It is concluded that loss of a middle leg disrupts the motor pattern less severely than does loss of a rear leg. The implications of this and other results for the understanding of motor control are discussed.

Amputation, Surgical↗
PubMed1990

Effect of dietary sodium bicarbonate on leg structure in Duroc swine that differ genetically for leg weakness.

Two trials were conducted to evaluate the effect of dietary replacement of .30% sodium chloride (NaCl) with a sodium-equivalent amount of sodium bicarbonate (NaHCO3) on leg weakness in swine. Three lines of Duroc swine established by six generations of divergent selection for front leg structure were used. In the first trial, a total of 80 low-line (increased leg weakness), 75 high-line (decreased leg weakness), 80 control-line (intermediate leg weakness) and 80 high x low pigs were used. Pigs were assigned within litter to an experimental or control diet and tested from approximately 37 to 104 kg live weight. The experimental diet contained .43% NaHCO3, replacing .30% NaCl in the control diet. Pigs had ad libitum access to feed. In the second trial, 48 high- and 48 low-line pigs were fed the same diets from 29 to 104 kg. At the completion of each trial, pigs were scored for various leg traits. The model used for statistical analyses included the effects of replicate, genetic line, dietary treatment and the dietary treatment x genetic line interaction. Trials were analyzed separately. Results indicated that there was no significant improvement in clinical signs of leg weakness due to dietary supplementation with NaHCO3 for front leg structure and movement, rear leg movement or rear toe size. Rear hock angle was improved in Trial 1 (P less than .05) but was reduced in Trial 2 (P less than .10).(ABSTRACT TRUNCATED AT 250 WORDS)

Animal Feed↗
PubMed1998

Differences in human antagonistic ankle dorsiflexor coactivation between legs; can they explain the moment deficit in the weaker plantarflexor leg?

The present study examined the hypothesis that the antagonistic ankle dorsiflexor coactivation level during maximum isometric voluntary plantarflexion (MVC) is a function of ankle angle. Six male subjects generated plantarflexion and dorsiflexion MVC trials at ankle angles of -15 deg (dorsiflexed direction), 0 deg (neutral position), +15 deg (plantarflexed direction) and +30 deg having the knee flexed at an angle of 90 deg. In all contractions surface EMG measurements were taken from tibialis anterior and soleus which were considered representative muscles of all dorsiflexors and plantarflexors, respectively. Antagonistic dorsiflexor coactivation was expressed as normalized EMG and moment. Calculations of the antagonistic dorsiflexor moment were based on the tibialis anterior EMG-dorsiflexor moment relationship from contractions at 50, 40, 30, 20 and 10 % of the dorsiflexion MVC moment. In both legs dorsiflexor coactivation level followed an open U-shaped pattern as a function of ankle angle. Differences of 9 and 14 % (P < 0.05) were found in the measured net plantarflexion MVC moment between legs at ankle angles of -15 and +30 deg, respectively. No difference (P > 0.05) was found in the calf circumference between legs. Differences were found in the antagonistic dorsiflexor coactivation between legs at ankle angles of -15 and +30 deg. In the weaker leg the antagonistic EMG measurements were higher by 100 and 45 % (P < 0.01) and the estimated antagonistic moments were higher by 70 and 43 % (P < 0.01) compared with the weaker leg at -15 and +30 deg, respectively. This finding was associated with a decreased range of motion (ROM) in the weaker leg (14 %, P < 0.01), such that no difference (P > 0.05) was found in dorsiflexor antagonistic coactivation between legs at end-range ankle angles. The findings of the study (i) have to be taken into consideration when estimating musculoskeletal loads in the lower extremity, (ii) imply that stretching training can result in a stronger plantarflexion at end-range ankle angles through inhibition of the dorsiflexors, and (iii) imply a neural drive inadequacy during a plantarflexion MVC at end-range angles.

Adult↗
PubMed1998

Reliability study of the Leg-O-Meter, an improved tape measure device, in patients with chronic venous insufficiency of the leg. VEINES Group.(Venous Insufficiency Epidemiologic and Economic Study).

The objective of this study was to evaluate the inter-rater reliability of the Leg-O-Meter, an instrument designed to measure the ankle or calf circumference. The Leg-O-Meter consists of a tape measure fixed to a stand attached to a small board on which the patient is in standing position. For this study the tape measure of the Leg-O-Meter was fixed at 10 cm from the board in order to standardize all measurements. Informed consent to participate in the study was obtained from 39 patients consulting the phlebology clinic of Hôpital St-Michel, Paris, France. Participants were asked to enter a closed room where four independent and blinded observers consecutively took measurements of both legs with the Leg-O-Meter. The order of the observers was randomized between patients. Under the assumption of a two-way random effects model an intraclass correlation coefficient (ICC) was used to determine the reliability or reproducibility of a measure with the Leg-O-Meter. The overall reliability coefficient calculated by the ICC for the right and left leg were estimated at 97.09% [95.52%;100%]95% and 97.08% [95.86%;100%]95%, respectively. The authors conclude that the Leg-O-Meter gives a standardized and reliable measure of the circumference of the ankle. Furthermore, it is not invasive or costly.

Analysis of Variance↗
PubMed2005

Assessment of nutritional status in adult patients with cystic fibrosis: whole-body bioimpedance vs body mass index, skinfolds, and leg-to-leg bioimpedance.

OBJECTIVE: To investigate whether body mass index (BMI) or body fat percentage estimated from BMI, skinfolds, or leg-to-leg bioimpedance are good indicators of nutritional status in adult patients with cystic fibrosis. Body fat percentage measured by whole-body bioimpedance was used as the reference method. DESIGN: Cross-sectional study using four methods to estimate body fat percentage. All patients filled out a food frequency and a physical activity questionnaire for assessment of their habitual food intake and energy requirements, respectively. SUBJECTS/SETTING: Thirty-five adult patients (23 men/12 women) with cystic fibrosis, age range 18 to 46 years, were measured during their yearly visit at the outpatient clinic of the Cystic Fibrosis Center in Utrecht, the Netherlands. STATISTICAL ANALYSIS: Mean+/-standard deviation was calculated for all measurements and 95% confidence intervals for differences between methods. Bland-Altman plots were used to assess differences between the measures of body composition and Pearson correlation coefficients were calculated to determine the relationships between them, and between the energy requirements and the energy intakes. RESULTS: For men the whole-body body fat percentage reference was 14.1%+/-3.0, body fat percentage estimated from BMI was 15.8%+/-4.3, body fat percentage estimated from skinfolds was 8.6%+/-4.8, and body fat percentage estimated from leg-to-leg bioimpedance was 13.1%+/-4.9. For women the whole-body body fat percentage reference was 24.0%+/-5.9, body fat percentage estimated from BMI was 25.1%+/-4.0, body fat percentage estimated from skinfolds was 17.0%+/-4.8, and body fat percentage estimated from leg-to-leg bioimpedance was 25.0%+/-6.9. Body fat percentage estimated from BMI and body fat percentage estimated from skinfolds were significantly different from the reference value for body fat percentage (P <.05). The correlation coefficients between the reference body fat percentage and body fat percentage estimated from BMI, from skinfolds, and from leg-to-leg bioimpedance were all more than 0.72. In all but one patient, nutritional status was correctly assessed by BMI: those with a BMI less than 18.5 had body fat percentage less than 10% (men) or less than 20% (women). The mean energy intake of the men was 141% of the Recommended Dietary Allowance as proposed in European and Dutch guidelines. The mean energy intake of the women was 94% of the Recommended Dietary Allowance. CONCLUSIONS: A simple calculation of BMI is adequate to diagnose nutritional status in adult patients with cystic fibrosis. Bioimpedance measurements are only needed when nutritional therapy specifically focuses on lean body mass.

Adipose Tissue↗
PubMed2001

Restless Legs Syndrome: scoring criteria for leg movements recorded during the suggested immobilization test.

Objective: To evaluate the characteristics of leg movements experienced by patients with the restless legs syndrome (RLS) during wakefulness using the suggested immobilization test (SIT).Methods: Forty patients with primary RLS who showed an index of leg movements greater than 40 during the SIT were selected for these analyses.Results: In general, Coleman's criteria for scoring PLMS were appropriate for scoring leg movements during the SIT. However, a substantial number of leg movements lasted between 5 and 10 s, exceeding Coleman's maximum duration criterion. The other criteria used to score PLMS (i.e. movements separated by 4-90 s and occurring in series of four consecutive movements) allowed detection of more than 90% of all leg movements recorded during the SIT. The distribution of inter-movement intervals (IMI) suggests that a great majority of leg movements recorded during the SIT are periodic, with a modal value of IMI between 11-12 s.Conclusion: Considering that leg movements recorded during the SIT last longer than those occurring during sleep, we recommend using a duration criterion of 0.5-10 s for scoring the former. We also recommend using the same periodicity criteria for the SIT as those used for scoring PLMS.

Journal Article↗
PubMed2005

Is leg-to-leg BIA valid for predicting minimum weight in wrestlers?

BACKGROUND: The National Collegiate Athletic Association (NCAA) and several state associations require prediction of minimum weight (MW) for collegiate and high school wrestlers. The rule requires assessment of body composition before the competitive season to minimize unhealthy weight-loss practices. Leg-to-leg bioelectrical impedance analysis (BIA) has been suggested for use with wrestlers. PURPOSE: To evaluate leg-to-leg BIA against a four-component (4C) criterion to determine whether leg-to-leg BIA predicted MW within acceptable limits for the sport of wrestling. METHODS: Criterion MW was calculated by the 4C equation of Lohman (19) using independent measurement of body density (BD) by hydrostatic weighing, bone mineral content (BMC) by dual x-ray absorptiometry (DXA), and total body water (TBW) by deuterium dilution. Subjects were 57 wrestlers (mean +/- SD; age = 19.7 +/- 1.3 yr, height = 176.6 +/- 7.3 cm, weight = 77.7 +/- 12.4 kg). Hydration was confirmed by the NCAA guidelines. Accuracy, precision, and systematic bias were examined. RESULTS: Comparable mean values (72.2 +/- 9.7 vs 72.2 +/- 10.3 kg), a high correlation (r = 0.94), and a regression line similar to the line of identity were found between BIA and 4C. However, large individual differences and systematic bias were seen across the range of MW. BIA predicted MW within 3.5 kg 68% of the time and within 7.0 kg 95% of the time. MW residuals ranged from -10.4 kg to +6.9 kg. When using 2.0 kg as an acceptable cutoff for error, only 40% of the BIA values were within 2.0 kg of the criterion. CONCLUSION: Large individual variation was seen, and, by definition, the precision was poor when estimating MW for individuals. In practical terms, the prediction error may span multiple weight classes, thus making leg-to-leg BIA unacceptable for prediction of MW in this sample under the conditions of the study.

Absorptiometry, Photon↗
PubMed2000

Leg ulcers in peripheral arterial disease (arterial leg ulcers): impaired wound healing above the threshold of chronic critical limb ischemia.

BACKGROUND: Peripheral arterial disease is the only identifiable etiology in approximately 10% of leg ulcers. Clinical data on the management of these chronic wounds are scarce. OBJECTIVE: We attempted to outline the threshold of systolic ankle pressure and ankle-brachial-index (ABI) below which arterial leg ulcers can occur and to outline the indication for revascularization in arterial leg ulcers. METHODS: Diagnostic and outcome analysis was performed for 26 consecutive patients with arterial leg ulcers. We calculated sensitivities, specificities, and receiver operating characteristic (ROC) curves for the identification of arterial leg ulcers among all 223 consecutive leg ulcer patients within a 3-year period, as well as the ROC curve for patients who required revascularization. RESULTS: The systolic ankle pressure was 88 (18-130) mm Hg (median; 95% confidence interval) and the ABI was 0.60 (0.15-0.86), respectively. Eighteen patients (69%) were subjected to revascularization. By the end of the study, 24 patients (92%) healed completely, 1 improved (90% wound closure), and 1 patient had to undergo below-knee amputation for chronic osteomyelitis. During this study, the ankle pressure and ABI were poor in distinguishing those patients who required revascularization from those who healed without revascularization. CONCLUSION: Most arterial leg ulcers do not meet the criteria of chronic critical limb ischemia, but they do not heal under conservative measures, either. A majority of these patients benefit from revascularization and should, therefore, be referred for arterial duplex ultrasound investigation or angiography. In our study, an ankle pressure below 110 mm Hg identified all patients (100%) who were subjected to revascularization procedures. However, controlled clinical studies are required to find the systolic ankle pressure and ABI below which revascularization can be recommended to speed up the healing time.

Aged↗
PubMed1998

Effect of pergolide on restless legs and leg movements in sleep in uremic patients.

Restless legs syndrome (RLS) and periodic limb movements in sleep (PLMS) are disorders that are common and disturbing to uremic patients. The treatment of these is problematic. Eight patients on chronic hemodialysis and continuous peritoneal dialysis completed a double-blind placebo-controlled crossover study using incremental doses of pergolide up to 0.25 mg at bedtime for treatment of RLS and sleep disruption. Five patients (62.5%) noted subjective improvement in restless legs symptoms and sleep quality. Objective results were improved only slightly by treatment. The percentage of the first hour in bed during which leg movements occurred decreased from 20.5 +/- 6.0 to 11.5 +/- 3.3, p < 0.05. However, findings during sleep were less positive. The following measures were not significant between placebo and treatment: leg movements per hour of sleep [53.7 +/- 22.3 vs 35.8 +/- 11.8 (p = 0.2)]; and percentage of sleep time spent with leg movements [5.5% +/- 3.2 vs 4.4% +/- 1.4 (p = 0.37)]. Patients continued to have very disrupted sleep, and we could not document an objective improvement in sleep architecture. Thus, although pergolide at the dose of 0.25 mg at bedtime provided subjective improvement in symptoms of restless legs and quality of sleep, and objectively decreased leg movements during the first hour in bed, objectively sleep continued to be disrupted. In this small patient group, the response to pergolide was not uniform, and further investigation is required to test effectiveness at higher doses.

Adult↗
PubMed1998

Leg blood flow during slow head-down tilt with and without leg venous congestion.

The effects of slow changes in body position on leg blood flow (LBF) were studied in nine healthy male subjects. Using a tilt table, sitting volunteers were tilted about 60 degrees backwards to a supine position within 40 s. To modify the venous filling in the legs, the tilt manoeuvre was repeated with congestion of the leg veins induced by two thigh cuffs inflated to a subdiastolic pressure of 60 mmHg. Doppler measurements in the femoral artery were used to estimate LBF. Additional Doppler measurements at the aortic root in five of the subjects were taken for the determination of cardiac output. The LBF was influenced by body position. In the control experiment it increased from 500 ml x min(-1) in the upright to 780 ml x min(-1) after 15 min in the supine position. A mean maximal value of 950 ml x min(-1) was observed 20 s after the tilt. Heart rate remained almost constant during the tilt phase, whereas stroke volume increased from 90 ml to 120 ml and it remained at that level after the cessation of the tilt. Congestion of the leg veins had no significant effect on heart rate, stroke volume and mean blood pressure. However, it increased vascular resistance of the leg during and after the tilt. After 15 min in the tilted position LBF amounted to 600 ml x min(-1). The results suggest that the filling of the leg veins is inversely related to leg blood flow. The most likely mechanism underlying this observation is a local effect of venous filling on vasomotor tone.

Adult↗