***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: PURPOSE The effects of upper-limb ( arm cranking ) and lower-limb ( leg cranking ) exercise training on walking distances in patients with intermittent claudication was assessed . METHODS Sixty-seven patients ( 33 to 82 years old ) with moderate to severe intermittent claudication were recruited , and the maximum power generated during incremental upper- and lower-limb ergometry tests was determined , as were pain-free and maximum walking distances ( by using a shuttle walk test ) . Patients were r and omly assigned to an upper-limb training group ( n = 26 ) or a lower-limb training group ( n = 26 ) . An additional  untrained group ( n = 15 ) was recruited on an ad hoc basis in parallel with the main trial by using identical inclusion criteria . This group was subsequently shown to possess a similar demographic distribution to the two exercise groups . Supervised training sessions were held twice weekly for 6 weeks . RESULTS Both training programs significantly improved the maximum power generated during the incremental upper- and lower-limb ergometry tests ( P < . 001 ) , which may reflect an increase in central cardiovascular function that was independent of the training mode . More importantly , pain-free and maximum walking distances also improved in both training groups ( P < .001 ) . The improvements in the training groups were similar ; there were no changes in the untrained control group . These findings suggest that the symptomatic improvement after upper-limb exercise training may result , in part , from systemic cardiovascular effects rather than localized metabolic or hemodynamic changes . CONCLUSION Carefully prescribed upper-limb exercise training can evoke a rapid symptomatic improvement in patients with claudication , while avoiding the physical discomfort experienced when performing lower-limb weight-bearing exercise BACKGROUND Recent data indicate that intermittent pneumatic compression ( IPC ) of the foot may offer benefits in patients with intermittent claudication exceeding those of st and ard medications approved by the Food and Drug Administration . IPC of the foot ( IPC(foot ) ) and calf ( IPC(calf ) ) increases flow velocity in infrainguinal arterial bypass grafts and thus may prevent arterial thrombosis . Our aim was to evaluate the acute effects of IPC of the thigh ( IPC(thigh ) ) , IPC(calf ) , and IPC of the thigh and calf ( IPC(calf + thigh ) ) in healthy controls , claudicants , and arteriopaths who have undergone infrainguinal bypass grafting for critical or subcritical limb ischemia . METHODS Sixteen limbs of normals ( group A ) , 17 limbs of claudicants ( group B ) , and 16 limbs of arteriopaths ( group C ) who had undergone infrainguinal autologous revascularization were studied . Blood flow was measured in the limbs of normals and claudicants in the popliteal artery and in the grafts of revascularized limbs by using duplex ultrasonography . Mean velocity ( mV ) , peak systolic velocity , end diastolic velocity ( EDV ) , pulsatility index ( PI ) , and volume flow ( Q ) were measured in the sitting position at rest and within 10 seconds from the delivery of IPC(thigh ) , IPC(calf ) , and IPC(calf + thigh ) , IPC was delivered at maximum inflation and deflation pressures of 120 mm Hg and 0 mm Hg , respectively ; inflation and deflation times of 4 and 16 seconds , respectively ; and a proximal inflate delay of 1 second ( calf compression preceding that of thigh ) . RESULTS In all 3 groups with all IPC modes , the Q , mV , and EDV increased while PI decreased ( P < .05 ) . IPC(thigh ) was less effective than IPC(calf ) , but still increased Q ( by 114 % , 57 % , and 59.8 % in groups A , B , and C , respectively ) and EDV , while decreasing PI in all 3 groups ( P < .05 ) . IPC(calf + thigh ) was the most efficient mode , generating an increase in the median Q of 424 % in controls , 229 % in claudicants , and 317 % in grafted arteriopaths . The addition of IPC(thigh ) to IPC(calf ) increased the mV and Q in group A ( P < or = .044 ) ; the mV , Q , and EDV in group B ( P < or = .03 ) , and mV and PI by 24 % and -27 % in group C , respectively . CONCLUSIONS IPC applied to the thigh , either alone or in combination with IPC(calf ) , generates native arterial and infrainguinal autologous graft flow enhancement . The paucity of conservative methods available for lower limb blood flow augmentation may allow IPC of the lower limb to emerge as a reliable , noninvasive therapeutic option , ameliorating claudication and assisting infrainguinal bypass graft flow .  IPC(thigh ) adds to the armamentarium of currently known IPC options ( foot or calf ) promoting its applicability and efficacy PURPOSE the aim was to investigate the effect of intermittent pneumatic foot compression ( IPC(foot ) ) on popliteal artery haemodynamics in normal individuals and in patients with intermittent claudication due to peripheral vascular disease ( PVD ) ( Fontaine stage II ) . MATERIAL AND METHODS popliteal artery volume flow [ vFl ] , pulsatility index [ PI ] , mean velocity [ mV ] , peak systolic [ PSV ] and end diastolic velocity [ EDV ] , in 25 limbs of 20 normal subjects and 40 limbs of 32 stable claudicants were obtained in the sitting position before , during and within 30 seconds after the application of IPC(foot)(applied pressure : 120 mmHg ; inflation time : 3 seconds ; deflation time : 17 seconds ) using colour-flow duplex imaging ( CFDI ) . The reproducibility of flow velocity estimations using CFDI in the horizontal [ hor ] ( recovery ) and sitting [ sit ] positions was evaluated in 20 limbs of normal controls and 20 limbs of claudicants . RESULTS popliteal artery vFl , mV , PSV and PI measurements were performed with a coefficient of variation ( CV ) of less than 14.6 % among claudicants and of less than 13.3 % in normal subjects . EDV is the least reproducible parameter with an overall CV range of 10.2 - 21.5 % in normal controls and 9.1 - 18.6 % in arteriopaths . On application of IPC(foot)popliteal  artery vFl increased by 111 % in the control group ( p<0.001 ) and by 51 % in the claudicants ( p<0.001 ) . Within 30 seconds of the cessation of pump action flow decreased significantly in both groups ( p<0.001 ) , but maintained a significantly higher level than that at baseline ( p<0 . 001 , in both groups ) . The mV , PSV and EDV showed a similar pattern of significant changes . Both in normals and claudicants , the PI decreased with IPC(foot)(p<0.001 ) and increased post-compression ; however , it was significantly lower than baseline ( p<0.005 ) within 30 seconds of impulse delivery . CONCLUSIONS current CFDI technology enables a reproducible estimation of popliteal artery flow velocities .  IPC(foot)can significantly augment arterial calf inflow on an acute basis both in normals and claudicants . The increase of EDV and decrease of PI indicate that attenuation of peripheral resistance to flow is the main mechanism underlying the popliteal artery vFl enhancement on application of IPC(foot ) . Prospect i ve trials on the long-term effect of IPC(foot)in the management of patients with PVD are indicated from the results of this study INTRODUCTION Intermittent pneumatic compression ( IPC ) is currently being investigated with respect to its effect on distal arterial volume flow in patients with peripheral vascular disease . Recently published data have shown a substantial acute enhancement in arterial calf inflow in response to IPC of the lower limb in both intermittent claudication and leg ischemia . PURPOSE The aim of the study was to compare the immediate effects of intermittent pneumatic foot ( IPC(foot ) ) versus calf ( IPC(calf ) ) versus simultaneous foot and calf compression ( IPC(foot+calf ) ) on popliteal artery hemodynamics in patients with intermittent claudication ( Fontaine II ) and in normal subjects , using duplex ultrasonography . For this purpose , 25 limbs of 20 healthy subjects ( age range [ mean ] , 51 - 74 [ 64 ] years ) and 31 limbs of 25 claudicants ( age range [ mean ] , 56 - 81 [ 66.5 ] years ; resting ankle-brachial indices , 0.38 - 0.75 [ 0.55 ] ) were examined in the sitting position with and without IPC compression . RESULTS Mean popliteal artery flow in healthy subjects increased by 98.8 % on application of IPC(foot ) , 188 % with IPC(calf ) , and 274 % with IPC(foot+calf ) ( all P < .001 ) . Mean flow in claudicants increased by 58 % on application of IPC(foot ) , 132 % with IPC(calf ) , and 174 % with IPC(foot+calf ) ( all P < .001 ) . The mean velocity , peak systolic velocity , and end diastolic velocity displayed a pattern of change similar to that for volume flow in both groups . Pulsatility index decreased in both groups on application of IPC ; the lowest values were generated with IPC(foot+calf ) . CONCLUSION Of the three compression modes investigated , IPC(foot+calf ) was the most effective means of acutely augmenting arterial calf inflow in arteriopaths and normals . The significant increase in end diastolic velocity and decrease in pulsatility index indicate that peripheral vasodilatation is the central mechanism in this impulse-related flow augmentation . Prospect i ve trials are indicated to determine the clinical potential of the long-term effects of IPC(foot+calf ) in patients with symptomatic peripheral vascular disease External pneumatic calf compression is effective but imperfect for antithrombotic prophylaxis in surgical patients . In preliminary studies , sequential filling of multisegmented leggings with grade d pressure decreasing from ankle to knee increased venous flow velocity and wall shear stress , decreased residual venous volume , and enhanced postoperative fibrinolysis more than uniform compression . To determine if improved hemodynamics also increased antithrombotic activity , we performed a prospect i ve r and omized trial in neurosurgical patients comparing sequential application of grade d pressure with uniform pressure applied to either a segmented bladder or to a single bladder .  Deep vein thrombosis  was diagnosed by leg scanning and impedance plethysmography and confirmed by phlebography .  Venous thrombosis developed in 3 of 45 patients with  grade d-sequential filling , 6 of 50 with uniform compression-multiple compartments , and 3 of 41 with uniform pressure single bladder ( differences not significant ) . These results suggest either that uniform compression offers all that can be expected of external pneumatic calf compression in prevention of venous thrombosis , or that even if a study with greater statistical power showed grade d-sequential filling to be superior , the benefit/cost ratio of the more complex latter system is not likely to be large PURPOSE Intermittent pneumatic foot compression ( IPC(foot ) ) augments arterial leg inflow . It has been suggested that prolonged use of impulse leg compression at home might ameliorate claudication caused by peripheral vascular disease by improving collateral circulation . The purpose of this study was to determine the effect of IPC(foot ) treatment on claudication distance and arterial hemodynamics in patients with intermittent claudication caused by peripheral vascular disease . METHODS Thirty-seven patients with stable intermittent claudication were admitted to this prospect i ve controlled study . Of these , 25 patients received IPC(foot ) ( > 4 hr/d ) for 4.5 months ( group 1 ) , and the other 12 patients acted as control patients ( group 2 ) . Both groups were advised to exercise unsupervised for a minimum of 1 hour daily and received aspirin ( 75 mg/d ) . Groups were matched for age , sex , risk factors , claudication distances , and ankle pressures at baseline . In each patient , initial claudication distance ( ICD ) , absolute claudication distance ( ACD ) , resting ankle brachial index ( r-ABI ) , ankle brachial pressure index after exercise ( p-eABI ) , and popliteal artery volume flow were measured at day 0 , 2 weeks , and 1 , 2 , 3 , and 4.5 months . On completion of the treatment period ( 4.5 months ) , both groups continued with aspirin ( 75 mg/d ) and unsupervised exercise and were re-examined after 12 months . Data analysis is based on nonparametric statistics , the Wilcoxon signed ranks test , and the Mann-Whitney test for intragroup and intergroup comparisons , respectively . Results are expressed as median and interquartile ranges . RESULTS Over the 4.5 months of active treatment , ( 1 ) median ICD in group 1 increased by 146 % ( P < .001 ) , from 78 m ( interquartile range , 65 - 102 m ) at baseline to 191.5 m ( interquartile range , 127 
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The diverse patient criteria and methods used in the studies provided an opportunity to examine the effectiveness of each , but made it difficult to compare one study with another .
In conclusion , it is evident that an intermittent pneumatic compression program appears promising and may be used in patients with severe peripheral arterial disease who are not c and i date s for revascularization using surgery or percutaneous angioplasty .