Criteria for reliable selection of the lowest level of amputation in peripheral vascular disease.

To improve the chances for the amputee to become ambulatory the most distal level of amputation should be selected in patients with end-stage peripheral vascular disease. Physical examination alone provides insufficient information when amputation levels are closely related to areas with signs and symptoms of ischemia. In the present series of 85 lower extremity amputations the predictive values of clinical parameters and skin perfusion pressure measurements are assessed. The role of clinical judgment is clarified: the most distal level of amputation is to be selected by physical examination, but further information is required to assess the healing potential at the selected level. The presence of palpable pulses immediately above the selected level correlates well with primary wound healing (p less than 0.001, negative predictive value 100%). The absence of palpable pulses and angiographic patency scores are of no clinical value in amputation level selection. Skin perfusion pressure measurements were of excellent predictive value (p less than 0.001, positive predictive value 89%, negative predictive value 99%). According to these data a strategy is proposed for routine determination of the lowest level of amputation, where primary wound healing can be expected.

Use of passive function testing in venous insufficiency: a prospective study.

In a prospective study, the results of venous function tests in 19 lower extremities with deep venous insufficiency and in seven control extremities were compared. First, the routine method of asking the patients to exercise their calves was used. Second, cuffs around the calves were rapidly inflated, producing standardized external compression to the calf muscle pump. Our aim was to decrease the influence of artifacts from involuntary muscle efforts and especially to render reproducible results of pressure reduction after passively pumping. The passive function test proved to be the only technique with which a decrease in pressure measured with strain gauges while the patient was in the standing position could significantly be discriminated between diseased and control extremities. Furthermore, the correlation of pressure decrease invasively versus measured noninvasively improved to 37% and thus became significant. Simulating calf venous pump function with the aid of inflatable cuffs is easily applicable in the vascular laboratory. It enables the vascular surgeon to reliably quantify venous recovery time and pressure reduction.

Construction of peritoneal venous valves: an experimental study in rats and piglets.

In the search for new techniques to improve venous valve insufficiency, a peritoneal patch with a mesothelial layer on either side was employed in the venous circulation to construct a venous valve de novo. This material was used because of the resemblance in fibrinolytic activity of mesothelial cells to endothelium. The behavior of double-sided flaps of peritoneum was first studied on only one side in the caval vein wall of 10 rats. All veins remained open, and smooth incorporation of the patch into the vein wall was observed. It was therefore decided to use the same material for construction of a cusp blade in the venous circulation. This venous reconstruction was microsurgically performed in 21 rats and 4 piglets. In our hands, intramuscular anesthesia proved superior to intraperitoneal analgesia in rats. For the piglets mechanical ventilation and general anesthesia were used. In 9 of 21 rats a fair or good result was observed, although it did not seem possible to create a fully competent valve with only one cusp blade in the 1.5-mm-diam caval veins. The same fact evolved from the study using four 7-mm-diam piglet veins. All peritoneal flaps in the venous circulation demonstrated rebuilding of their structure, perhaps induced by the relatively exaggerated central venous flow. To our knowledge, this technique has never been used before. It seems to offer many advantages in the venous circulation, where hardly any thrombogenic surface is tolerated in contrast to the arterial circulation. Application in humans is yet premature, but future research may resolve several problems that occurred in this study.

A multivariate analysis of determinants of wound healing in patients after amputation for peripheral vascular disease.

In a prospective study 53 patients undergoing amputations of the lower limb were evaluated for clinical criteria, laboratory results, pulse volume recordings, Doppler pressures, Photoplethysmographic Skin Perfusion Pressures (PPG/SPP) and angiography. The purpose of the study was to analyse which of these techniques predicts wound healing adequately after amputation. Forty-five patients eventually completed all tests. With the exception of PPG/SPP none of these tests were able to predict skin healing. The technique of PPG/SPP proved very reliable in helping to select the level of amputation, if measured anteriorly (P = 0.0001, r = 0.83). Angiographic scoring also correlated significantly (P = 0.0016) with a successful result. This study suggests that surgeons should not rely on their clinical acumen for the selection of the amputation level. In the absence of a reliable non-invasive test, angiography may well be useful but PPG/SPP will enable the surgeon to amputate on an optimal level and thus reduce complications and improve rehabilitation.

The correlation of peroperative outflow resistance measurements with patency 109 infrainguinal arterial reconstructions.

The predictive value of outflow resistance measurements for the patency of femoro-popliteal and femoro-crural bypass grafts was analysed. Peroperative outflow resistance measurements were performed in 109 infrainguinal arterial reconstructions. Outflow resistance was significantly higher in occluded bypasses compared with those which remained open (P less than 0.01), but there was a considerable overlap of values in both groups. Statistical analysis of the correlation between outflow resistance and patency rates at 3 months revealed a marginal correlation in the femoro-popliteal bypass group (R = -0.25), which was not significant (P = 0.064). In the femorocrural bypass group there was again only a marginal correlation (R = -0.27) but this was statistically significant (P = 0.05). These data demonstrate that intraoperative outflow resistance measurements are only of limited value for predicting bypass patency in individual cases.

Failure of quantitative venous photoplethysmography to assess venous insufficiency: a prospective clinical study.

The increase of deep venous reconstructive surgery necessitates reliable tests for evaluation of the results, which requires quantization of the expelled volume. This could only be done with invasive measurements, but now it seems possible to calibrate photoelectric cells, and quantize the results. Nineteen limbs of patients with deep venous disease and seven limbs of healthy volunteers were evaluated, with methods known from the literature. In addition to measurements in standing position, these methods were used in the more patient-friendly sitting position. Invasively and noninvasively measured recovery times correlated well in the standing (R = 0.83) and in the sitting position (R = 0.86). However, the quantization of expelled volume did not significantly correlate. Also, the differences between expelled volume of controls and patients were only significant with invasive measurements in the standing position (P = 0.006) as well as in the sitting position (P = 0.004). The differences were not significant with the noninvasive method. In our opinion, photoelectric cells still do not offer an alternative for invasive measurements in the evaluation of results after venous reconstructive surgery.

Intermittent claudication and limb-threatening ischemia in systemic lupus erythematosus and in SLE-like disease: a report of two cases and review of the literature.

Intermittent claudication and limb-threatening ischemia caused by occlusion of large and medium-sized arteries are rare manifestations of systemic lupus erythematosus. So far only eight documented cases have been reported, predominantly in young women. In this report two more patients are described. There is no common opinion concerning pathophysiologic mechanism, but immunologic endothelial damage and circulating antibodies to phospholipid probably play a role. The results of medical and surgical treatment are disappointing, and amputation becomes necessary in more than half of the patients.

Morbidity in a microsurgical rat training model.

In a prospective study with 24 growing Wistar rats, with a mean body weight of 300 gram, microsurgery was trained. Patency as well as morbidity of the animals was assessed. There were 110 vascular anastomoses, constructed with various techniques. Of these, 104 were rendered for evaluation. The caliber of the vessels varied from 0.4 to 2.0 mm. On an average, the rats were operated two times, during which operations at least four anastomoses were created. Patency was related to caliber and flow rate of the vessel and varied between 50 and 100%. Mortality and weight increase, used to reflect morbidity were evaluated. Six animals died during or shortly after operation, three of them because of anaesthesia alone. Mean postoperative daily weight increase was 1 gram approximately. In the control group the weight increase was tripled. The rats needed two weeks after operation rats to regain their original weight. Analysis of results demonstrated highly significant difference between operated and non-operated rats. The study suggests, that morbidity of rats submitted to microsurgery will be reduced, if two weeks of recovery before other experiments are awaited. This may provide a standard for future experiments.

A modified scintigraphic technique for amputation level selection in diabetics.

A modified 123I-antipyrine cutaneous washout technique for the selection of amputation levels is described. The modifications imply a reduction of time needed for the examination by simultaneous recordings on different levels, and a better patient acceptance by reducing inconvenience. Furthermore, both skin perfusion pressure (SPP) and skin blood flow (SBF) are determined from each clearance curve. In a prospective study among 26 diabetic patients presenting with ulcers or gangrene of the foot, both SPP and SBF were determined preoperatively on the selected level of surgery and on adjacent amputation sites. These 26 patients underwent 12 minor foot amputations and 17 major lower limb amputations. Two of these amputations failed to heal. SBF values appeared indicative for the degree of peripheral vascular disease, as low SBF values were found with low SPP values. SPP determinations revealed good predictive values: all surgical procedures healed when SPP greater than 20 mmHg, but 2 out of 3 failed when SPP less than 20 mmHg. If SPP values would have been decisive, the amputation would have been converted to a lower level in 6 out of 17 cases. This modified scintigraphic technique provides accurate objective information for amputation level selection.

Photoplethysmographic selection of amputation level in peripheral vascular disease.

In a prospective study 37 patients who required amputations of the leg were studied with a new technique: segmental photoplethysmographic skin perfusion pressures. The decision to amputate was made by a vascular surgeon in a traditional manner, with the aid of clinical criteria. The simple method of determining skin perfusion pressures with photoplethysmography is described; 273 measurements were performed. The technique proved to be highly correlated (r = 0.88) with wound healing after amputation, at a separating value of 21 mm Hg (p = 0.0001). The study suggests that the value of this noninvasive method will be to enable the surgeon to amputate at a lower level and to diminish complications and failure of rehabilitation.

Spontaneous subclavian vein thrombosis: a successful combined approach of local thrombolytic therapy followed by first-rib resection.

In 17% to 74% of patients with subclavian vein thrombosis, conservative treatment or venous thrombectomy led to residual symptoms. To improve these results, a prospective study was started in patients with subclavian vein thrombosis who were treated with a combined approach of local thrombolytic therapy followed by a first-rib resection. From 1983 to 1987 five patients entered the protocol. Total lysis was achieved in all cases. In the follow-up period, phlebography and strain-gauge plethysmography according to Whitney showed no recurrent thrombosis. All patients were able to resume their normal activities.

A technique to prevent aneurysm formation in microvascular anastomoses.

The occurrence of true aneurysm formation in microarterial anastomoses is well known. In up to 50% of microanastomoses this complication is found. In a microsurgical training group a new technique was taught, which did not give cause to any aneurysm formation at all. This technique allows only suturing with relative thin and many stitches, suturing of small edges of the vessel wall and short stripping of adventitia. Though operative skill perhaps is more demanding in this new technique, the merits are clear.

Horizontal rotation of the patella. A case report with review of the literature.

In a 14-year-old boy a direct blow caused the patella to rotate around its horizontal axis; the articular surface faced distally. Thirty-two cases have been described previously.