Application Of Intermittent Pneumatic Compression Research Articles

Can foot compression under a plaster cast prevent deep-vein thrombosis during lower limb immobilisation?

We hypothesised that adjuvant intermittent pneumatic compression (IPC) beneath a plaster cast would reduce the risk of deep-vein thrombosis (DVT) during post-operative immobilisation of the lower limb. Of 87 patients with acute tendo Achillis (TA) rupture, 26 were prospectively randomised post-operatively after open TA repair. The treatment group (n = 14) received two weeks of IPC of the foot for at least six hours daily under a plaster cast. The control group (n = 12) had no additional treatment. At two weeks post-operatively all patients received an orthosis until follow-up at six weeks. At two and six weeks the incidence of DVT was assessed using colour duplex sonography by two ultrasonographers blinded to the treatment. Two patients withdrew from the study due to inability to tolerate IPC treatment. An interim analysis demonstrated a high incidence of DVT in both the IPC group (9 of 12, 75%) and the controls (6 of 12, 50%) (p = 0.18). No significant differences in incidence were detected at two (p = 0.33) or six weeks (p = 0.08) post-operatively. Malfunction of the IPC leading to a second plaster cast was found to correlate with an increased DVT risk at two weeks (ϕ = 0.71; p = 0.019), leading to a premature abandonment of the study. We cannot recommend adjuvant treatment with foot IPC under a plaster cast for outpatient DVT prevention during post-operative immobilisation, owing to a high incidence of DVT related to malfunctioning of this type of IPC application.

What influence does intermittent pneumatic compression of the lower limbs intraoperatively have on core hypothermia?

Intermittent pneumatic compression (IPC) devices have been widely used for thrombosis prophylaxis in laparoscopic colorectal surgery. However, periodic compression using an IPC device may inject augmented boluses of cool blood from the lower limbs into the central circulation repetitively, thereby causing a reduction in core temperature. The authors therefore conducted a prospective, randomized, double-blind, controlled study to compare the effects of intraoperative IPC on core temperature in patients undergoing laparoscopic colorectal surgery. For this study, 56 patients ages 18-60 years and scheduled to undergo laparoscopic resection for colorectal cancer under general anesthesia were randomly assigned to receive either no IPC (control group) or calf-thigh-length IPC in both legs using the SCD Express (IPC group). Anesthetic, thermal, and pneumoperitoneum management were standardized. Esophageal temperature, as an indicator of core temperature, was measured at 15-min intervals for 2 h after induction of anesthesia. A total of 47 subjects (23 control and 24 IPC subjects) were included in the analysis. The core temperature drop in the IPC group was significantly greater than in the control group, starting from 45 min after induction of anesthesia (P < 0.05). As a result, the total temperature drop during the 2-h study period was significantly greater in the IPC group (1.2 ± 0.3 °C) than in the control group (0.9 ± 0.3 °C) (P = 0.004). Because intraoperative application of IPC carries an increased risk of a core temperature drop, appropriate temperature monitoring and active thermal management are required for surgical patients receiving IPC.

The effect of sequential intermittent pneumatic compression of foot and calf on popliteal artery mean systolic blood flow in patients with intermittent claudication

To determine the effect of intermittent pneumatic foot and calf compression on popliteal artery mean systolic blood flow in patients with intermittent claudication. The secondary objective was to determine the change in blood flow with posture. This was a cross sectional study carried out on claudication patients at the Vascular Laboratory, Department of General Surgery, Kuala Lumpur Hospital, from January 2009 to August 2009. The effect of posture (supine to sitting to standing) and the effect of intermittent pneumatic compression (IPC) of the foot and calf on popliteal artery flow immediately and 10 minutes post compression were studied. Fifteen patients were studied. There was a consistent drop in flow from supine to sitting and to standing in all patients. Immediately after IPC application there was an increase in flow ranging from 29-335% (p<0.05). Increase in flow was reduced but still sustained after 10 minutes with a flow range of 17-113mL/minute with a median of 63mL/minute (p<0.05). There is a significant reduction in popliteal artery mean systolic flow from supine to sitting and to the standing position, and popliteal artery flow is significantly increased after application of IPC and even persists after 10 minutes.

Effects on Changes in Femoral Vein Blood Flow Velocity with the Use of Lower Extremity Compression for Critical Patients with Brain injury

This study was done to evaluate the mean venous velocity (MVV) response with knee and thigh length compression stockings (CS) versus intermittent pneumatic compression (IPC) devices in immobile patients with brain injuries. We carried out a randomized controlled study. We analyzed both legs of a randomly chosen sample of 43 patients assigned to one of 4 groups (86 legs). The patients were sequentially hospitalized in the intensive care unit (ICU) in "S hospital" from November 2005 to December 2006. The base line and augmented venous velocity was measured at the level of the common femoral vein. We applied leg compression 42 times over 7 days (for 2 hours at a time at 2 hour intervals). There was a statistical difference among the 4 groups. The difference for the "IPC" group was more significant than the "CS" group. These results indicate that the application of IPC can be considered as an effective method to prevent deep vein thrombosis for immobile patients with brain injury.

Integrity of venoarteriolar reflex determines level of microvascular skin flow enhancement with intermittent pneumatic compression

To investigate whether intermittent pneumatic compression (IPC) augments skin blood flow through transient suspension of local vasoregulation, the veno-arteriolar response (VAR), in healthy controls and in patients with peripheral arterial disease (PAD). Nineteen healthy limbs and twenty-two limbs with PAD were examined. To assess VAR, skin blood flow (SBF) was measured using laser Doppler fluxmetry in the horizontal and sitting positions and was defined as percentage change with postural alteration [(horizontal SBF--sitting SBF)/horizontal SBF x 100]. On IPC application to the foot, the calf, or both, SBF was measured with laser Doppler fluxmetry, the probe being attached to the pulp of the big toe. Baseline VAR was higher in the controls 63.8 +/- 6.4% than in patients with PAD (31.7 +/- 13.4%, P = .0162). In both groups SBF was significantly higher with IPC than at rest (P < .0001). A higher percentage increase with IPC was demonstrated in the controls (242 +/- 85% to 788 +/- 318%) than in subjects with PAD, for each one of the three different IPC modes investigated (98 +/- 33% to 275 +/- 72%) with IPC was demonstrated. The SBF enhancement with IPC correlated with VAR for all three compression modes (r = 0.58, P = .002 for calf compression, r = 0.65, P < .0001 for foot compression alone, and r = 0.64, P = .0002 for combined foot and calf compression). The integrity of the veno-arteriolar response correlates with the level of skin blood flow augmentation generated with intermittent pneumatic compression, indicating that this may be associated with a transient suspension of the autoregulatory vasoconstriction both in healthy controls and in patients with PAD.

Thromboseprophylaktischer Effekt intermittierend komprimierender, pneumatischer Strümpfe (IPC): Eine systematische Literaturanalyse

Despite changes in patient demographics and short-ened length of hospital stay deep vein thrombosis (DVT) remains a major health care problem which may lead to a variety of other high risk complications. Current treatment guidelines focus on preventive measures. Beside drug therapy, physical measures executed by nursing professionals exist, the outcomes of which are discussed controversially. Based on 25 studies that were found in MEDLINE and the Cochrane library, this systematic literature review identifies the effectiveness of intermittent pneumatic compression (IPC) on thrombosis prophylaxis. In almost all medical settings IPC contributes to a significant reduction of the incidence of DVT. At the same time, IPC has minimal negative side effects and is also cost effective. Correct application of IPC and patient compliance are essential to achieve its effectiveness. An increased awareness within the healthcare team in identifying the risk for and implementing measures against DVT is needed. Guidelines need to be developed in order to improve the effectiveness of thrombosis prophylaxis with the implementation of IPC.

Intermittent pneumatic compression regulates expression of nitric oxide synthases in skeletal muscles

This study investigated the effects of intermittent pneumatic compression (IPC) on expression of nitric oxide synthase (NOS) isoforms in compressed (anterior tibialis, AT) and uncompressed (cremaster muscles, CM) skeletal muscles. Following IPC application of 0.5, 1, and 5 h on both legs of rats, the endothelial NOS (eNOS) mRNA expression was significantly up-regulated to 1.2-, 1.8, and 2.7-fold from normal, respectively, in both AT and CM, and protein expression increased more than 1.5-fold of normal at each time point. Similarly, neuronal NOS expression was up-regulated, but to a lesser degree. In contrast, inducible NOS expression was significantly and time-dependently down-regulated in both muscles. After IPC cessation, eNOS levels returned to normal in both AT and CM. The results confirm our hypothesis that IPC-induced vasodilation is mediated by regulating expression of NOS isoforms, in particular eNOS, in both compressed and uncompressed skeletal muscles. The results also suggest the importance of precisely characterizing expression of each NOS isoform in tissue pathophysiology.

Hemodynamic effects of intermittent pneumatic compression in patients with critical limb ischemia

Traditional teaching assumes that the distal arterial tree is maximally dilated in patients with critical limb ischemia (CLI). Endovascular or arterial bypass procedures are the commonly used interventions to increase distal perfusion. However, other forms of treatment such as spinal cord stimulation or intermittent pneumatic compression (IPC) have been shown to improve limb salvage rates. This prospective study was designed to determine if the use of IPC increases popliteal, gastrocnemial, collateral arterial, and skin blood flow in patients with CLI. Twenty limbs with CLI in 20 patients (mean age, 74 years) were evaluated with duplex ultrasound scans and laser Doppler fluxmetry in the semi-erect position before, during, and after IPC. One pneumatic cuff was applied on the foot and the other on the calf. The maximum inflation pressure was 120 mm Hg and was applied for 3 seconds at three cycles per minute. All patients had at least two-level disease by arteriography. Fourteen limbs were characterized as inoperable, and six were considered marginal for reconstruction. Flow volumes were measured in the popliteal, medial gastrocnemial, and a genicular collateral artery. Skin blood flux was measured on the dorsum of the foot at the same time. Significant flow increase during the application of IPC was found in all three arteries (18/20 limbs) compared with baseline values (P < .02). The highest change was seen in the popliteal, followed by the gastrocnemial and the collateral artery. After the cessation of IPC, the flow returned to baseline. This was attributed to the elevation of time average velocity, as the diameter of the arteries remained unchanged. The skin blood flux increased significantly as well (P < .03). In the two limbs without an increase in the arterial or skin blood flow, significant popliteal vein reflux was found. Both limbs were amputated shortly after. IPC increases axial, muscular, collateral, and skin blood flow in patients with CLI and may be beneficial to those who are not candidates for revascularization. Patients with significant venous reflux may not benefit from IPC. This supports the theory that one of the mechanisms by which IPC enhances flow is by increasing the arteriovenous pressure gradient.

Role of nitric oxide in vasodilation in upstream muscle during intermittent pneumatic compression.

This study investigated the dosage effects of nitric oxide synthase (NOS) inhibitor N(G)-monomethyl-L-arginine (L-NMMA) on intermittent pneumatic compression (IPC)-induced vasodilation in uncompressed upstream muscle and the effects of IPC on endothelial NOS (eNOS) expression in upstream muscle. After L-NMMA infusion, mean arterial pressure increased by 5% from baseline (99.5 +/- 18.7 mmHg; P < 0.05). Heart rate and respiratory rate were not significantly affected. One-hour IPC application on legs induced a 10% dilation from baseline in 10- to 20-microm arterioles and a 10-20% dilation in 21- to 40 microm arterioles and 41- to 70-microm arteries in uncompressed cremaster muscle. IPC-induced vasodilation was dose dependently reduced, abolished, or even reversed by concurrently infused L-NMMA. Moreover, expression of eNOS mRNA in uncompressed cremaster muscle was upregulated to 2 and 2.5 times normal at the end of 1- and 5-h IPC on legs, respectively, and the expression of eNOS protein was upregulated to 1.8 times normal. These increases returned to baseline level after cessation of IPC. The results suggest that eNOS plays an important role in regulating the microcirculation in upstream muscle during IPC.

The acute effects of intermittent pneumatic foot versus calf versus simultaneous foot and calf compression on popliteal artery hemodynamics: A comparative 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 (IPCfoot) versus calf (IPCcalf) versus simultaneous foot and calf compression (IPCfoot+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 IPCfoot, 188% with IPCcalf, and 274% with IPCfoot+calf (all P <.001). Mean flow in claudicants increased by 58% on application of IPCfoot, 132% with IPCcalf, and 174% with IPCfoot+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 IPCfoot+calf. Conclusion: Of the three compression modes investigated, IPCfoot+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. Prospective trials are indicated to determine the clinical potential of the long-term effects of IPCfoot+calf in patients with symptomatic peripheral vascular disease. (J Vasc Surg 2000;32:284-92.)

Influences of Inflation Rate and Duration on Vasodilatory Effect by Intermittent Pneumatic Compression in Distant Skeletal Muscle

Previous study has demonstrated that application of intermittent pneumatic compression on legs can cause vasodilation in distant skeletal muscle at the microcirculation level. This study evaluated the influence of inflation rate and peak-pressure duration on the vasodilatory effects of intermittent pneumatic compression. The cremaster muscles of 50 male rats were exposed and divided into five groups of 10 each. A specially designed intermittent pneumatic-compression device was applied in a medial-lateral fashion to both legs of all rats for 60 minutes, with an inflation rate and peak-pressure duration of 0.5 and 5 seconds, respectively, in group A, 5 and 0 seconds in group B, 5 and 5 seconds in group C, 10 and 0 seconds in group D, and 10 and 5 seconds in group E. Diameters of arterial segments were measured in vessels of three size categories (10-20, 21-40, and 41-70 microm) for 120 minutes. The results showed that the greatest increase in diameter was produced by intermittent pneumatic compression with the shortest inflation rate (0.5 seconds). A moderate increase resulted from compression with an inflation rate of 5 seconds, and no effective vasodilation occurred during compression with the longest inflation rate (10 seconds). When the groups with different inflation rates but the same peak-pressure duration were compared, there was a significant difference between any two groups among groups A, C, and E and between groups B and D. When the groups with different peak-pressure durations but the same inflation rate were compared, compression with a peak-pressure duration of 5 seconds caused a generally similar degree of diameter change as did compression without inflation at peak pressure. The findings suggest that inflation rate plays an important role in the modulation of distant microcirculation induced by intermittent pneumatic compression whereas peak-pressure duration does not significantly influence the vasodilatory effects of the compression. This may be due to the fact that rapid inflation produces a significant increase in shear stress on the vascular wall, which stimulates vascular endothelium to release nitric oxide, causing systemic vasodilation.

Influences of inflation rate and duration on vasodilatory effect by intermittent pneumatic compression in distant skeletal muscle.

Previous study has demonstrated that application of intermittent pneumatic compression on legs can cause vasodilation in distant skeletal muscle at the microcirculation level. This study evaluated the influence of inflation rate and peak-pressure duration on the vasodilatory effects of intermittent pneumatic compression. The cremaster muscles of 50 male rats were exposed and divided into five groups of 10 each. A specially designed intermittent pneumatic-compression device was applied in a medial-lateral fashion to both legs of all rats for 60 minutes, with an inflation rate and peak-pressure duration of 0.5 and 5 seconds, respectively, in group A, 5 and 0 seconds in group B, 5 and 5 seconds in group C, 10 and 0 seconds in group D, and 10 and 5 seconds in group E. Diameters of arterial segments were measured in vessels of three size categories (10-20, 21-40, and 41-70 microm) for 120 minutes. The results showed that the greatest increase in diameter was produced by intermittent pneumatic compression with the shortest inflation rate (0.5 seconds). A moderate increase resulted from compression with an inflation rate of 5 seconds, and no effective vasodilation occurred during compression with the longest inflation rate (10 seconds). When the groups with different inflation rates but the same peak-pressure duration were compared, there was a significant difference between any two groups among groups A, C, and E and between groups B and D. When the groups with different peak-pressure durations but the same inflation rate were compared, compression with a peak-pressure duration of 5 seconds caused a generally similar degree of diameter change as did compression without inflation at peak pressure. The findings suggest that inflation rate plays an important role in the modulation of distant microcirculation induced by intermittent pneumatic compression whereas peak-pressure duration does not significantly influence the vasodilatory effects of the compression. This may be due to the fact that rapid inflation produces a significant increase in shear stress on the vascular wall, which stimulates vascular endothelium to release nitric oxide, causing systemic vasodilation.

The Effects of Intermittent Pneumatic Compression on Systemic and Local Fibrinolysis

Intermittent pneumatic compression (IPC) is effective in deep venous thrombosis prophylaxis. IPC prevents venous stasis by collapsing the peripheral venous plexus in an extremity leading to increased venous return. It has been suggested that IPC has an additional effect of enhancing fibrinolysis. This study was designed to evaluate the effect of IPC on both systemic and local fibrinolysis in normal volunteers by measuring the activity of tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-type 1 (PAI-1). In addition, tissue factor pathway inhibitor (TFPI) was measured to assess changes in the extrinsic coagulation cascade. IPC was applied in the foot and calf of 10 healthy subjects and blood was drawn from the antecubital fossa to determine systemic fibrinolytic activity. Local fibrinolysis was assessed in 15 healthy subjects by placing an IPC cuff on the forearm and drawing blood 2 cm above the cuff The IPC maximum inflation pressure was 120 mm Hg lasting for 3 seconds at three cycles per minute. Blood samples were taken at rest, on the 10th minute of active IPC, and 5 minutes after cessation of IPC for both systemic and local measurements. The plasma was analyzed for TFPI, t-PA, and PAI-1 antigen by use of enzyme-linked immunosorbent assays. There were no significant changes in systemic or local fibrinolytic activity before, during, or after application of IPC. TFPI systemic activity before, during, and after was 111 ±24, 118 + 18, and 116 ±22, respectively. Local TFPI activity was 91 ±32, 93 +36, and 91 ± 24, respectively. The t-PA systemic activity before, during, and after was 4.1 ± 1.9, 4.7 ± 2.3, and 5 + 2.8, respectively. Local t-PA activity was 4.5 ± 1.3, 4.5 ± 1.4, and 4.2 ± 1.4, respectively. Systemic PAI-1 activity was 11 ± 9.2, 17 ± 19, and 17 ±31, respectively. Local PAI-I activity was 3.7 ± 3.1, 3 ± 1, and 2.8 + 1, respectively, p &gt; 0.38 for all comparisons in both groups. No evidence was found that IPC enhances systemic and local fibrinolysis or TFPI release. Irrespective of the length of IPC application or the inflation pressure, several studies have reported increased fibrinolysis, whereas others have not found any changes. Although, according to the literature, there is a trend toward increased fibrinolytic activity, further controlled studies with adequate sample size should be performed to provide an answer to this controversial topic.

Intermittent pneumatic compression of legs increases microcirculation in distant skeletal muscle.

Intermittent pneumatic compression has been established as a method of clinically preventing deep vein thrombosis, but the mechanism has not been documented. This study observed the effects of intermittent pneumatic compression of legs on the microcirculation of distant skeletal muscle. The cremaster muscles of 80 male rats were exposed, a specially designed intermittent pneumatic-compression device was applied to both legs for 60 minutes, and the microcirculation of the muscles was assessed by measurement of the vessel diameter in three categories (10-20, 21-40, and 41-70 microm) for 120 minutes. The results showed significant vasodilation in arterial and venous vessels during the application of intermittent pneumatic compression, which disappeared after termination of the compression. The vasodilation reached a maximum 30 minutes after initiation of the compression and could be completely blocked by an inhibitor of nitric oxide synthase, NG-monomethyl-L-arginine (10 micromol/min). A 120-minute infusion of NG-monomethyl-L-arginine, beginning coincident with 60 minutes of intermittent pneumatic compression, resulted in a significant decrease in arterial diameter that remained at almost the same level after termination of the compression. The magnitude of the decrease in diameter in the group treated with intermittent pneumatic compression and NG-monomethyl-L-arginine was comparable with that in the group treated with NG-monomethyl-L-arginine alone. The results imply that the production of nitric oxide is involved in the positive influence of intermittent pneumatic compression on circulation. It is postulated that the rapid increase in venous velocity induced by intermittent pneumatic compression produces strong shear stress on the vascular endothelium, which stimulates an increased release of nitric oxide and thereby causes systemic vasodilation.

Effects of intermittent pneumatic compression of the foot on the microcirculatory function in arterial disease

The venous pump of the foot assists blood returning to the heart. The aim of this study was to evaluate the effect of mechanical activation of the foot pump on the microcirculation of the skin in patients with peripheral occlusive arterial disease. Single parallel group comparing patients with arterial disease to normal control subjects. Department of Surgery, the University College and Middlesex Hospital, London, U.K. 15 patients with peripheral occlusive arterial disease and 15 control subjects. A pneumatic impulse foot pump was applied to the foot. The Laser Doppler flux (LDF) and transcutaneous oxygen tension (tcPO2) were measured on the big toe with the subject supine, before, during and after a 10 min period of foot pumping. The study was repeated with the subject sitting. On sitting there is a fall in LDF and rise in tcPO2. Application of intermittent pneumatic compression of the foot in the sitting position resulted in an increase in LDF. In patients, the median percentage increase was 57% and the median difference was 82 arbitrary units (AU) (95% CI 60-130, p < 0.001). In controls, the median percentage increase was 66% and the median difference was 124 AU (95% CI 73-275 p < 0.001). There was a corresponding "further" increase in tcPO2 in both groups of subjects. In patients, the median percentage increase was 8%, in controls the median percentage increase was 10% p < 0.01). We conclude that intermittent pneumatic compression of the foot in the dependent position increases LDF and tcPO2.