Skin Damage in Chronic Venous Insufficiency: Does an Oxygen Diffusion Barrier Really Exist?

Eleven patients with lipodermatosclerosis (LDS) and 14 patients without venous or arterial disease underwent measurement of xenon-133 (133Xe) half-clearance times from the gaiter region of the leg. Xenon has similar diffusion characteristics to oxygen, and the investigation reflects the ability of the isotope to diffuse from the skin surface into capillary blood. Median skin half-clearance time for skin in the LDS group was 2.2 min and in the control group 2.1 min. From the subcutaneous tissues, the respective times were 14.1 and 17.4 minutes. These differences are not statistically significant. The study fails to yield evidence suggesting that an oxygen diffusion barrier exists in lipodermatosclerosis.

Vasomotion in Venous Disease

Abnormalities of the capillary microcirculation may be important in the pathogenesis of venous ulceration. In this study the characteristics of capillary vasomotion in venous disease have been studied using laser Doppler flowmetry.

The amplitude and frequency of vasomotion in the skin microcirculation as measured by laser Doppler flowmetry was determined in 101 subjects. These comprised 43 subjects with venous disease and lipodermatosclerosis (LDS), 14 subjects with uncomplicated varicose veins (VV), and 44 normal controls. In 43 of these 101 limbs, vasomotion was also measured after heating the skin to 43°C.

The resting laser Doppler flux was significantly higher in the LDS group compared to the other two groups (LDS median=76, VV median=47 (P < 0.04), controls median=49 (P < 0.003)). The amplitude of vasomotive waves was significantly higher in the LDS group compared to controls (LDS median=20, VV median=8.3 (P < 0.007), controls median=14 (P < 0.007)), as was the frequency of vasomotion (LDS median=3.3 waves/min, VV median=2.5 (P=ns), controls median=2.7 (P < 0.007)).

On heating the skin to 43 °C the frequency of the vasomotion increased significantly in the control (P < 0.004) and VV (P < 0.04) groups but not in the LDS group. The amplitude of the vaso-motion also increased significantly in the control (P < 0.01) and VV (P < 0.002) groups but not in the LDS group. Following heating, the frequency of vasomotive waves was significantly lower in the LDS group than in controls (P=0.05).

Drug Treatment of Chronic Venous Insufficiency and Venous Ulceration: A Review

Treatment of venous insufficiency and venous ulceration has for many years relied on established principles of compression and limb elevation. Drug treatment has been of little benefit. In recent years, a better understanding of the pathological mechanisms underlying skin damage in venous disease has allowed more rational pharmacotherapeutic approaches to be made. This review examines these, with special reference to current theories of the cause of venous ulceration.

Liposclerotic Skin: A Diffusion Block or a Perfusion Problem?

There is continued debate as to whether skin damage in venous disease results from an oxygen diffusion block or from abnormal perfusion.

Transcutaneous oxygen pressure and laser-Doppler flux were measured in 15 patients with chronic venous insuffiency (CVI) and lipodermatosclerosis and in 15 normal controls. The time for Tc Po2 to regain resting values after 5 min of ischaemia was measured, as was the time taken for laser-Doppler flux to reach 95% of peak flow.

Tc Po2 was reduced in patients with CVI (median 26 mmHg, interquartile range (IQR) 16–46) compared to controls (median 55 mmHg, IQR 40–65). Hyperaemic responsiveness, as assessed by calculating the ratio of peak laser-Doppler flux following 5 min of ischaemia, was also reduced (median (CVI) 1.5, IQR 1.1–2; median (control 3.3, IQR 1.8–4.8). However, following ischaemia Tc Po2 took no longer to regain resting levels in venous patients than in controls, whereas there was a trend towards delay in reaching peak skin blood flow.

These findings suggest a primary perfusion deficit in skin damaged by venous hypertension rather than an oxygen diffusion block.

Three Tests of Microcirculatory Function in the Evaluation of Treatment for Chronic Venous Insufficiency

No investigation exists which has been shown to detect accurately microcirculatory improvement following treatment for chronic venous insufficiency. This study examines three possible techniques for doing so.

Fourteen patients with chronic venous insufficiency and fourteen controls underwent measurement of transcutaneous PO2, 133xenon clearance from the skin and subcutaneous tissues and laser–Doppler flowmetry in the gaiter region. Patients with venous disease then followed a regime of intermittent pneumatic compression for 4 h each day for 4 weeks. The same measurements were then repeated. Xenon clearance from subcutaneous fat and the time taken to reach maximal laser–Doppler flow after release of a tourniquet showed a significant improvement after compression treatment. These tests may be useful as parameters in the objective monitoring of response to treatment in patients with liposclerotic skin.

Two-Dimensional Laser Doppler Perfusion Imaging and Microcirculatory Function in Patients with Venous Skin Damage

Objective:

To assess the use of two-dimensional laser Doppler perfusion imaging in the quantification of venous skin damage.

Design:

Comparison of disease group with control group.

Setting:

Department of Medicine, Hôpital du Nord, Grenoble, France.

Subjects:

Six patients (nine limbs) with lipodermatosclerosis (LDS) due to duplex-proven venous insufficiency and six controls subjects (11 limbs).

Interventions:

Perfusion images were collected at rest, after venous hypertension and after skin heating.

Main outcome measures:

Mean skin perfusion (mV).

Results:

An increased basal flux at rest was found in lipsclerotic skin (1.6 V) compared with controls (0.94, V, 95% CI = 0.16–1.48). An impairment of hyperaemic responsiveness to heat was also shown (factor of increase = 1.87 (LDS) compared with 3.28 (controls); 95% CI = 0.85–2.44).

Surgical Options in Post-Thrombotic Syndrome

Objective:

To review the outcome of surgical restoration of deep vein competence in 53 patients with post-thrombotic syndrome.

Design:

Single patient group.

Setting:

Unite de Pathologie Vasculaire Jean Kunlin, Clinique du Grand-Large, av. Leon-Blum, Decines Charpieu, France.

Patients:

Fifty-three patients with clinical and radiological evidence of post-thrombotic syndrome uncontrolled by conventional conservative treatment.

Interventions:

Surgical restoration of deep vein competence by one of four methods: valvuloplasty, vein transplantation, vein transposition, or Psathakis' sling procedure.

Main outcome measures:

Sustained ulcer healing, photoplethysmography (PPG) refilling times, abolition of venous reflux on duplex scanning, symptomatic improvement.

Results:

All four techniques led to sustained ulcer healing in approximately two-thirds of patients. There was a poor correlation between maintenance of ulcer healing and improvement in PPG refilling times or abolition of reflux on duplex ultrasound.

Deep Vein Reflux is Reduced by Compression of the Foot Venous Plexus

A venous pump exists on the lateral side of the foot. Eleven patients with popliteal vein reflux were examined using Duplex scanning. The ratio of retrograde to antegrade flow in the popliteal vein following compression of the calf muscles was compared to the ratio following compression of the lateral side of the foot. Nine of the eleven patients studied exhibited proportionately less popliteal vein reflux following foot compression than calf compression ( P < 0.02). The reasons are not clear but the findings raise the possibility that augmentation of venous return by foot compression may be beneficial in patients with deep venous insufficiency.

Peroperative Venography in Sapheno-Popliteal Ligation: Still a Useful Technique

Objective:

To establish the efficacy of peroperative venography in identifying the use of the sapheno-popliteal junction during varicose vein surgery.

Design:

Single patient group.

Setting:

District General Hospital, Edgware, Middlesex, UK.

Patients:

Forty-one patients undergoing sapheno-popliteal ligation for varicose veins of the lower limb.

Interventions:

Surgical exploration and ligation of the sapheno-popliteal junction.

Main outcome measures:

Peroperative venographic demonstration of the short saphenous vein and sapheno-popliteal junction.

Results:

Thirty-four sapheno-popliteal junctions (85%) lay at a site approachable by a conventional incision. Five junctions lay higher than this and one lower.

Conclusions:

On-table venography is an efficient, quick and reliable way of demonstrating the anatomical site of the sapheno-popliteal junction.

Investigation of Popliteal Fossa Venous Reflux

Objective:

To assess the relative diagnostic merits of duplex scanning (DS) and dynamic popliteal phlebography (DPP) in the investigation of popliteal fossa venous reflux.

Design:

Prospective single patient study.

Setting:

Departments of Vascular Surgery, Radiology and Angiology, Jean Kunlin Unit of Vascular Pathology, Clinique du Grand-Large, Declines Charpieu, France.

Patients:

Eighteen consecutive patients with venous reflux in the popliteal fossa as demonstrated by hand-held Doppler insonation.

Interventions:

All limbs were investigated by DS and DPP before undergoing surgical exploration of the Popliteal fossa.

Main outcome measures:

The findings of the two modes of investigation were compared with the operative findings.

Results:

Both tests showed good specificity (98% DPP, 96% DS), but only moderate sensitivity (83% DPP, 87.5% DS). Both tests were wrong in two limbs.

Conclusion:

Phlebography can be reserved for cases where duplex scanning is inconclusive. Unsuspected anomalies will occasionally be found at operation despite exhaustive investigation.

Primary Venous Aneurysms of the Popliteal Fossa

Objective:

To report five cases of primary venous aneurysm arising in the popliteal fossa.

Setting:

Unite de Pathologie Vasculaire Jean Kunlin, Clinique du Grand-Large, av. Leon-Blum, Decines Charpieu, France.

Patients:

Five patients with radiological evidence of venous aneurysm in the popliteal fossa.

Interventions:

Surgical repair in all cases.

Main outcome measures:

Avoidance of pulmonary embolism.

Results:

Satisfactory postoperative recovery in all. No complications or subsequent pulmonary emboli.

Radiotherapy-related axillary artery occlusive disease: percutaneous transluminal angioplasty and stenting. Two case reports and review of the literature

Radiotherapy-related axillary artery occlusive disease is a relatively rare condition. This complication is usually encountered in patients with breast carcinoma treated by radiotherapy and might be frequently concealed by the presence of lymphoedema. We discuss this rare complication of radiotherapy treatment for breast cancer and present two cases and their successful treatment by a modified percutaneous transluminal angioplasty and stenting technique. A review of literature on the subject is also presented.

Lichen planus following varicose vein surgery

Six weeks after varicose vein surgery, a patient presented with an intensely irritating, florid, purple, papular rash. This matched the line of long saphenous vein stripping and avulsions perfectly. A diagnosis of lichen planus was made by a consultant dermatologist and confirmed histologically by biopsy. Treatment with topical corticosteroids resulted in a dramatic improvement and the rash healed to leave pigmentation.

Open access carotid duplex scanning: throughput and resultant surgical workload

It is now generally accepted that high-quality duplex scanning obviates the need for pre-operative angiography in the assessment of most cases of carotid disease. An information leaflet was circulated to all general practitioners and hospital doctors in early 1996. Indications, results of treatment and details of the open access service were described. This paper outlines the workload that followed, for both imaging and surgical departments.

Effect of left renal vein division during aortic surgery on renal function

A total of 398 consecutive patients underwent surgery for an aneurysm or occlusive disease of the aorta at Norfolk and Norwich Hospital between December 1994 and October 1998. It was necessary to divide the left renal vein in 58 (14.6%) cases. We examined the effect of this division on the mortality rate and renal function. Renal function was assessed by measuring serum creatinine pre-operatively, peri-operatively and long-term postoperatively. There was no significant difference in the mortality rate between patients who had the left renal vein divided (LRVD) and in whom the left renal vein remained intact (LRVI)--31% versus 32%, P = 0.83. There was no significant difference in the pre-operative serum creatinine level between both groups (107 +/- 21 mumol/l in LRVD versus 103 +/- 29 mumol/l in LRVI, P = 0.14). There was an insignificant rise in the mean serum creatinine 7 days postoperatively (111 +/- 21 mumol/l in LRVD versus 107 +/- 31 mumol/l in LRVI, P = 0.05). The mean serum creatinine returned back to the pre-operative level at 30 days postoperatively (106 +/- 16 mumol/l in LRVD and 105 +/- 29 mumol/l, P = 0.20). After 1 month, there was no significant difference in the number of patients who had a sustained elevation of serum creatinine level (7.5% in LRVD versus 2.7% in LRVI, P = 0.11). We feel that division of the left renal vein is a safe and helpful procedure during juxtarenal aortic surgery.

The case against a national screening programme for aortic aneurysms

This review examines the assumptions underlying the calls for a national screening programme for aneurysms. It concludes that on the basis of published evidence, many of the necessary criteria for any putative screening programme are not met for this disease. Although the disease is an important cause of death, and a screening method is available, we lack basic knowledge about the natural history of the disease, especially small aneurysms, and about the cost-effectiveness of a screening programme. In particular, the treatment is an operation which, nationwide, carries a high mortality and is likely to be unacceptable to many patients. The consequences of such a programme would be to diagnose many small aneurysms, for which the best treatment remains unclear, and which will engender much unnecessary anxiety among patients so diagnosed.

Venous valve repair: early results in fifty-two cases

PURPOSE

Chronic deep venous insufficiency, usually secondary to the postthrombotic syndrome, is due to primary valve failure in approximately 15% of cases. In these cases surgical repair of the valvular mechanism may be indicated.

METHODS

Fifty-two limbs in 42 patients were treated with superficial femoral vein valvuloplasty after appropriate investigation. Adjunctive operations on the superficial or perforating veins were performed on 49 limbs during the same hospital admission.

RESULTS

Of the 27 patients who have completed one year of follow-up, 85% are free of reflux on duplex scanning and 68% have had normalization of venous refilling times. Of 11 limbs with venous ulceration followed up for more than 1 year, only one has had a recurrent ulcer (9%). In patients without ulceration the procedure has been successful in alleviating symptoms of venous insufficiency.

CONCLUSIONS

We conclude that the procedure, in conjunction with appropriate superficial venous operation, is effective in selected patients with deep vein reflux whose conditions remain uncontrolled by conservative measures. At 1 year, 85% of valvuloplasties in this series remained competent.

Hyperaemic response in the skin microcirculation of patients with chronic venous insufficiency

The capacity of the microcirculation in the liposclerotic skin of patients with chronic venous insufficiency to vasodilate in response to pilocarpine electrophoresis was assessed using laser Doppler fluxmetry. Pilocarpine induces vasodilation by direct action on capillaries; other methods of vasodilatation, such as heating of the skin, act by a number of pathways including a neurogenic one. Thirty patients with lipodermatosclerosis and chronic venous insufficiency and 20 control subjects were studied. There was no difference in peak vasodilatation following pilocarpine electrophoresis in the two groups. The median (interquartile range) peak flux in patients was 665 (382-1025) units and in controls 765 (452-975) units (95 per cent confidence interval of difference--270 to 150 units, P = 0.5). This suggests that the capillaries in the liposclerotic skin of patients with chronic venous insufficiency have a normal capacity to vasodilate.

Venous ulcers and the superficial venous system

PURPOSE

The purpose of this study is to identify the anatomic location of venous disease in patients with venous ulceration and chronic venous insufficiency.

METHODS

Both limbs of 59 consecutive patients attending the Middlesex Hospital Vascular Laboratory (London, U.K.) with venous ulceration were assessed by color duplex ultrasound scanning to determine the location of venous disease.

RESULTS

Isolated deep venous reflux was present in only 12 limbs (15%). A combination of deep and superficial venous reflux was found in 25 limbs (32%), and in 42 limbs (53%) there was only superficial venous reflux.

CONCLUSION

In just over half the patients with venous ulceration, the disease is confined to the superficial venous system. This group of patients may benefit from surgical treatment. This study emphasizes the need for vascular laboratory investigation of patients with leg ulceration.

Marjolin's Ulcer: A Report of Three Cases and Review of the Literature

Objective:

To report three cases of Marjolin's ulcer and review the literature on the subject.

Design:

Case report.

Setting:

Edgware General Hospital, Edgware, Middlesex.

Patients:

Three patients presenting with Marjolin's ulcer.

Interventions:

Amputation (2 cases) and excision with skin grafting (1 case).

Main outcome measures:

Disease control.

Results:

Satisfactory control of disease in all three.

When do vascular surgeons prescribe antiplatelet therapy? Current attitudes

A large number of studies have addressed the efficacy of antiplatelet agents in the prevention of primary and secondary atherosclerotic events. We have undertaken to review the literature and conclude that there is good evidence for the routine prescription of antiplatelet therapy in the prevention of secondary atherosclerotic events in patients with unstable angina, myocardial infarction, transient ischaemic attacks and post-arterial reconstruction. The evidence for any benefit in the prevention of vascular graft occlusion is less clear cut. We therefore conducted a postal survey of Vascular Surgeons in Britain and Ireland, receiving 112 responses to 134 questionnaires. Forty-seven percent of surgeons used antiplatelet therapy following any vascular procedure that they undertook. The rest were more selective in their use of these drugs, reserving them for specific vascular reconstruction, e.g. with synthetic grafts. Five percent of surgeons used anti-platelet aggregating prophylaxis only in patients following transluminal balloon angioplasty. In view of extensive evidence of reduction in long-term vascular mortality and non-fatal vascular events by the use of these drugs in patients who have had a primary vascular event, we would suggest that there is a strong argument for the routine use of anti-platelet drugs in patients presenting with arterial disease to a Vascular Surgeon, regardless of vascular reconstruction, angioplasty or type of graft used.

Disease mechanisms in venous ulceration

Disease mechanisms in venous ulceration are poorly understood. Recent hypotheses have postulated two separate mechanisms to explain the extensive microcirculatory damage which leads, eventually, to ulceration. A number of treatments, based on the suggested pathogenesis, have been undertaken and this review critically examines these theories in the light of the results of these treatments.

Vasodilatory capacity of the skin in venous disease and its relationship to transcutaneous oxygen tension

Low transcutaneous oxygen tension (Ptc,O2) values in the supramalleolar skin of patients with venous disease are often reported. This measurement involves heating the skin to 43 degrees C to cause maximum vasodilatation and is valid only if liposclerotic and normal skin can vasodilate to the same degree. Forty-four limbs were studied, 15 with lipodermatosclerosis (LDS), 14 with uncomplicated varicose veins, and 15 controls. A Ptc,O2 electrode was modified to incorporate a laser Doppler probe. Laser Doppler flux was measured in the supramalleolar skin before and after local heating to 43 degrees C and the relative increase in flux was measured. The Ptc,O2 was then measured at the same site and on the chest. Vasodilatory capacity was expressed as the ratio of peak:basal laser Doppler flow, and the Ptc,O2 was expressed as a leg:chest ratio. Median laser Doppler flow was higher in limbs with LDS (median 67 mV) than in normal limbs (median 40 mV) (P less than 0.03). Ptc,O2 was higher in control limbs (median ratio 0.94) than in limbs with LDS (median 0.53) (P less than 0.006). The microcirculation in LDS had less capacity to vasodilate after heating (median factor of increase 5.4) than normal skin (median factor of increase 12.3) (P less than 0.001). A simple regression analysis was performed on all pairs of data, and revealed a correlation between Ptc,O2 and vasodilatory capacity (r = 0.524, P less than 0.001). The results indicate that low Ptc,O2 levels in venous disease reflect an inability of the microcirculation to increase its flow in response to local heating; inferences about the oxygen content of liposclerotic skin at normal temperatures cannot be drawn using this technique.

The pathogenesis of skin damage in venous disease: a review

Venous ulceration remains a major cause of morbidity. Treatment has not improved significantly in recent years, possibly because our understanding of the pathophysiological mechanisms at work is still incomplete. We review the principal abnormalities found in the macro- and microcirculation in this condition and discuss the various theories put forward to explain the mechanism by which skin damage occurs.

Near-infrared spectroscopy in peripheral vascular disease

Near-infrared spectroscopy has been performed on the calf muscles of 38 subjects, 21 normal controls without vascular disease and 17 patients with peripheral vascular disease. Oxygen consumption was measured in the calf by calculating the rate of conversion of oxyhaemoglobin to deoxyhaemoglobin during a period of tourniquet-induced ischaemia. Postischaemic reoxygenation was also measured. Median oxygen consumption in patients with peripheral vascular disease was 0.10 ml 100 g tissue-1 min-1, while in the control group it was 0.20 ml 100 g tissue-1 min-1 (P less than 0.03, Mann-Whitney U test). The median time taken to reach maximum oxyhaemoglobin levels after ischaemia was 40 s in patients with peripheral vascular disease and 20 s in controls (P less than 0.02). The results indicate that oxygen consumption is reduced in peripheral vascular disease. Near infrared spectroscopy is a non-invasive method for assessing metabolic improvement resulting from surgical or pharmacological treatment.

The effect on skin blood flow of short-term venous hypertension in normal subjects

Plugging of skin capillaries by activated white blood cells is one of the proposed mechanisms by which skin damage may be initiated in chronic venous insufficiency. The aim of this study was to determine whether a microcirculatory deficit was induced in the skin by raising the venous pressure proximally for thirty minutes. Seventeen subjects with no evidence of venous or arterial disease had laser Doppler velocimetry performed in the goiter region of the leg; 8 different subjects had the measurement done on the dorsum of the hand. Peak hyperemic response following three minutes of ischemia was measured before and after a thirty-minute period of sustained venous hypertension applied by a proximal tourniquet inflated to 80 mm Hg. A decrease in the peak flow: baseline flow ratio (median ratio 2.25 before, 1.70 after, p less than 0.02) and an increase in the time taken to reach maximal hyperemia (median time ten seconds before, twenty seconds after, p less than 0.01) were observed after the period of venous hypertension in the lower limb. The second parameter, but not the first, was significantly affected in the upper limb. The authors conclude that a microvascular deficit in the skin is demonstrable after a short period of venous hypertension. This is consistent with the white-cell-trapping theory, but other possible explanations are discussed.

Reappraisal of the oxygenation of blood in varicose veins

Raised oxygen tension in the blood of varicose veins has led to arteriovenous communications being implicated in the pathogenesis of varicose veins. The aim of this study was to compare the oxygen tension of blood from varicose veins with that from normal legs, and to observe the effect of posture on these measurements. Twenty-six subjects (13 normal controls and 13 with uncomplicated varicose veins) had blood sampled from the long saphenous vein or a varicose vein near the ankle. Samples were taken after 30 min in the supine position and repeated after 30 min standing. Samples were also taken simultaneously from the arm. Transcutaneous oxygen measurements of the gaiter skin were performed continuously throughout the experiment. In the supine position, blood from varicose veins had a significantly higher oxygen tension (median = 6.09 kPa) than that from normal veins (median = 4.54 kPa) (P = 0.022). In all subjects, there was a higher oxygen tension in leg vein blood when lying (varicose vein median value = 6.09 kPa, control median value = 4.54 kPa) than while standing (varicose vein median value = 3.93 kPa, control median value = 3.74 kPa) (P less than 0.002, varicose vein group; P = 0.005, normal group). Changes in transcutaneous oxygen tension correlate poorly with changes in venous blood. It is concluded that the theory of arteriovenous anastomoses is only one among a number of possible explanations for the pathogenesis of varicose veins.

Abdominal aortic aneurysms: a review of current problems

This review examines the aetiology and possible methods of prevention of abdominal aortic aneurysm. The natural history of the lesion is discussed. Given its poor prognosis, surgery should be considered even when the patient is over 80 years of age, has stable cardiovascular disease and has a small aneurysm. The case for population screening is reviewed and potential areas of advance in management are outlined.