Chemical lumbar sympathectomy for ischemic rest pain. A randomized, prospective controlled clinical trial.

The results of a randomized, controlled, prospective double-blind trial of phenol chemical sympathectomy against placebo bupivacaine injection in 41 limbs (24 treatment and 17 control) have been presented. Ablation of the skin potential response was used as an indication of successful sympathectomy. Rest pain was relieved in 83.5 percent of patients at 1 week with a placebo response of 23.5 percent (chi-square test, p less than 0.002). Sixty-six percent of patients remained free from rest pain at 6 months (chi-square test, p less than 0.02). The ankle-brachial systolic pressure index and resting and peak (reactive hyperemic) blood flows were measured in the foot; there was no demonstrable improvement in these hemodynamic factors. Chemical sympathectomy in these circumstances is probably acting as a pain-relieving injection but nevertheless produces useful remission of rest pain in these inoperable but otherwise relatively stable patients. It can also be employed while relevant investigations are carried out before direct arterial surgery.

Geometry, blood flow, and reconstruction of the deep femoral artery.

The deep femoral artery is the main source of blood supply to the leg and foot when the superficial femoral artery is occluded. In this situation, the geometry of the trunk of the deep femoral artery represents a stenosis of 50 per cent interposed between the common femoral artery and the collateral circuit of the deep femoral artery. Intimal thickening of only 0.5 and 1.0 mm increases this anatomic stenosis to 64 and 76 per cent, respectively. Beyond the trunk, the cross-sectional area of the deep femoral artery circuit increases at each arterial division. Any reconstruction of the deep femoral artery intended to increase its inflow must extend down to at least its first important bifurcation if it is to overcome this trunk "stenosis". This requirement ex plains the effectiveness of proper reconstruction of the deep femoral artery in avoiding or delaying amputation in patients with ischemic symptoms and occlusion of the superficial femoral artery who are not candidates for femoropopliteal reconstruction. In this group, the absence of plaque on the arteriogram does not contraindicate reconstruction.

Raynaud's phenomenon: a review.

Raynaud's phenomenon is a final result of many disease processes and is rarely a primary dysfunction and more an autoimmune phenomenon. It seems to be the result of a failure of vasodilatation than a sympathetic overactivity. Digital arteries are affected in only 40%, more often the fault is at the arteriolar and capillary level. The controlling mechanism of small vessels seems intact but the role of central versus peripheral factors is unresolved. The method of thermal entrainment has shown the action of sex hormones on vascular control especially at the time of ovulation. Heredity is a major factor in aetiology, myxoedema is common (16%). The role of prostaglandin metabolism is not clear. Platelets are hyperactive, blood viscosity is raised and red cells more rigid than normal. Sympathectomy fails in 81% of cases.

The computer as a tool in the diagnosis and treatment of peripheral vascular disease.

The application of a mini computer to a routine diagnostic vascular laboratory has been assessed in over 4,500 patients over a period of 5 years. The laboratory functions to provide diagnosis of peripheral vascular disease. The computer functions are: scientific, in which it is used for modelling the arterial system and for applying diagnostic algorithms using haemodynamic signals re-input data, data base management, in which it is used to store clinical histories, the results of haemodynamic tests, and data for reconstructive surgery, and administrative, in which it is used for laboratory booking, report generation and management and workload statistics.

The effect of adjuvant oxygen therapy on transcutaneous pO2 and healing in the below-knee amputee.

The effects on tissue oxygenation of postoperative adjuvant oxygen have been studied in a group of 20 patients undergoing below-knee (BK) amputation for vascular disease. Ten patients received no therapy, the remainder receiving 28% oxygen for 48 hours following surgery. The results showed that the transcutaneous pO2 in the amputation flaps fell significantly by some 20 mmHg (p less than 0.01) following surgery and that this fall was prevented by the use of adjuvant oxygen. The fall was not observed in the non-amputated limbs. TcpO2 took almost two weeks to reach its pre-operative levels in the amputated limbs. The effect on stump healing of adjuvant oxygen therapy was investigated in a randomized controlled trial in a series of 39 patients undergoing BK amputation. There were 22 patients in the control (untreated) group and 17 in the treated group (adjuvant oxygen for 48 hours). In the treated group 14 patients healed primarily and three amputations failed. In the untreated group 14 limbs healed primarily, one secondarily and there were 7 failures. The pre-operative transcutaneous values in the stumps which failed (26 mmHg +/- 14) was significantly lower (p less than 0.005) than in those which healed (40 mmHg +/- 9). The mean pre-operative TcpO2 in the patients in whom healing occurred in the treated group (35 mmHg +/- 10) was significantly lower (p less than 0.001) than the mean pressure observed in the untreated group (44 mmHg +/- 9).

Sexual function following aortoiliac reconstruction.

Impotence due to atherosclerotic disease of the aorta and iliac arteries presents as failure to achieve erection. Sterility after aortoiliac reconstructive surgery is more common and presents as inability to ejaculate. If the superior hypogastric sympathetic plexus (presacral nerve) is preserved, sexual function can be maintained in 90% of cases.

Extended deep femoral angioplasty: an alternative to femoropopliteal bypass.

The results of extended deep femoral angioplasty (EDFA) have been alaysed for 74 legs in 72 patients. In 69 per cent a femoropopliteal bypass would have been possible, so DEFA is considered here as an alternative operation. The success rate was 66-9 per cent, the failure rate 25-6 per cent and no effect was achieved in 7-5 per cent. Diabetes adversely affected the results. Of the failures, 45 per cent were diabetic, while the incidence of diabetes was only 14 per cent in the group where the operation was successful. The long term results of the operation were reasonable, 75 per cent being successful for 10-39 months. Age had no bearing on success or failure. The effects of EDFA were most dramatic on intermittent claudication. In 52 per cent it was abolished and in 92 per cent claudication distance was increased to over 200 yards. Good results were achieved after failed lumbar sympathectomy and failed femoropopliteal bypass. Successful results of EDFA could be predicted best by inspection of angiograms. Success or failure could have been predicted from the state of the run-off in 81 per cent of the cases. Claudication and rest pain were the most relieved by EDFA, followed by isachaemic ulceration of the leg. Gangrene of digits was helped but less than had been hoped. We conclude that the indications for femoropopliteal bypass are limited to cases of digital gangrene where angiography shows that bypass is possible or where an EDFA operation has failed.

Failure of low-dose heparin to improve efficacy of peroperative intermittent calf compression in preventing postoperative deep vein thrombosis.

The possible benefits of adding a low-dose heparin regimen to the technique of peroperative intermittent calf compression for preventing deep vein thrombosis (D.V.T.) were assessed in a randomized trial in 84 surgical patients. The efficacy of peroperative intermittent calf compression was not enhanced by a low-dose heparin regimen, but neither was it worsened. Age, weight, duration, operation, and malignant disease did not affect the relative effectiveness of the two regimens of prophylaxis. The results confirmed that venous stasis is the principal cause of D.V.T.

Involvement of the carotid artery in tumours of the head and neck.

Carotid artery involvement in neck tumours causes great concern to surgeons because of the unpredictable effects of carotid artery clamping or excision. Various methods of pre- and peroperative assessment of crossover cerebral circulation are reviewed. The management of 3 cases with extensive tumour involving the carotid artery is described. This comprises a combined operation involving a head and neck surgeon and vascular surgeon using a temporary carotid shunt followed by permanent autogenous vein graft to the internal carotid artery. It is suggested that thorough preoperative investigation combined with a more radical surgical approach can give a more satisfactory outcome in cases of head and neck tumours involving the carotid artery.

The measured effect of stopping smoking on intermittent claudication.

One hundred and twenty-four limbs in patients suffering from intermittent claudication were studied over 10 months. Changes in ankle pressure and treadmill exercise tolerance over the period were compared between two groups, one of patients who continued to smoke (group 1) and the other of those who gave up (group 2). Resting ankle systolic pressure fell in smokers' limbs by a mean of 10.2 mmHg (t = 3.56, P less than 0.001), and rose in those patients who stopped smoking by a mean 8.7 mmHg (P = n.s.). Ankle pressures after exercise and maximum treadmill walking distance did not change in smokers but significantly improved in past smokers. Stopping cigarette smoking increased the chance of improvement in ankle pressure and exercise tolerance in intermittent claudication.

Electromagnetic blood flow measurement during extended deep femoral angioplasty.

Electromagnetic flow measurements have been made on 53 patients undergoing extended deep femoral angioplasty. Flow measurements were made on the common femoral artery before reconstruction, after reconstruction and following an intra-arterial injection of papaverine. Flow measurements were correlated with the clinical outcome of the operation. The follow-up period varied between 6 and 30 months. There was no significant difference in follow-up period between the success and failure groups. The operation produced a significant increase in volume flow in both the success and the failure group. Flow velocities before and after reconstruction were, however, significantly higher in the success group. The results indicate that flow velocity measurement is preferable to volume flow measurement in assessing the long-term success of extended deep femoral angioplasty. A flow velocity of less than 5 cm per second achieved after reconstruction is likely to lead to failure; more than 10 cm per second indicates the likelihood of success.

Prevention of postoperative deep vein thrombosis in patients with malignant disease.

We have used the (125)I-fibrinogen test to asses the value of an improved method of peroperative intermittent calf compression as a prophylactic measure against postoperative thrombosis. In a group of 99 patients over the age of 40 undergoing operations lasting more than 30 minutes the technique reduced the incidence of postoperative thrombosis by over 75%. In patients suffering from malignant disease, who are generally considered to be in the very high risk category, the reduction achieved was almost 90%.

Prevention of early postoperative deep vein thrombosis by passive exercise of leg during surgery.

A clinical trial assessed the effect of passive exercise of the lower limb during surgery on the incidence of early postoperative deep vein thrombosis. Thrombosis was diagnosed by means of the (125)I-fibrinogen uptake test. Passive exercise of the lower limb during the operation was achieved by using a motorized foot mover designed for use on supine subjects, and by pedalling only one leg each patient acted as his own control.In a sequential statistical analysis, 47 patients were required to reach the 5% level of significance. Thrombosis was detected in 11 control (unpedalled) legs alone, and in only one pedalled leg alone. Two patients developed thrombosis bilaterally. The investigation shows that the incidence of early thrombosis in legs which were exercised during surgery was reduced by 77%.