Duplex detected ankle peak systolic velocity: a new parameter for the assessment of degree of peripheralischemia.

AIM: The objective of this study was to assess the sensitivity and specificity of a newly developed parameter: the ankle peak systolic velocity (APSV) to provide an objective assessment of the degree of peripheral ischemia. METHODS: In phase 1 of the study: data was prospectively collected for 21 ischemic limbs and 5 healthy volunteers. APSV was calculated as the mean value of the distal anterior and posterior tibial arteries peak systolic velocities (PSV). Ankle brachial index (ABI) was calculated for the anterior tibial and posterior tibial arteries. A mean ABI for both tibial arteries was also calculated. APSV was correlated with the mean ABI. Cut off values were calculated to differentiate critical, moderate and no ischemia. In phase 2 of the study data was prospectively collected for 37 ischemic limbs and 5 healthy volunteers, to assess the sensitivity and specificity of the cut off values of the APSV to identify limbs with critical ischemia, moderate ischemia, and no ischemia. RESULTS: APSV correlated strongly with the mean ABI (r=0.8, p<0.01). The sensitivity and specificity of APSV in identifying critical ischemia were 90% and 87%, for moderate ischemia they were 75% and 88%, and for differentiating limbs with any degree of ischemia from normal limbs they were 100% and 100%, respectively. CONCLUSIONS: APSV can be used as an alternative to ABI for the assessment of degree of peripheral ischemia.

Early experimental experience with a surgically created, totally autogenous venous valve: a preliminary report.

A surgically created, totally autogenous venous valve has been devised that holds potential for the treatment of venous insufficiency. Valves were constructed from 2.7 cm long segments of canine external jugular veins. Through the use of intimal separation, folding, and suturing techniques, thin, pliable valves with an intimal lining were constructed and interposed in the canine superficial femoral vein. Fifteen valves were implanted in three groups of dogs. In group I (six dogs) the valves were immediately removed after implantation and subjected to various levels of hydrostatic pressure. In group 2 (six dogs) valves were removed after 1 week and examined for patency and competency. Group 3 animals (three dogs) were anticoagulated with subcutaneously administered heparin from implantation to removal at 7, 9, and 13 days. In group 1 valves were found to open at less than 3 cm of water and remain competent at 55 cm of water. Two of these valves subjected to 300 mm Hg pressure also remained competent. In the six group 2 dogs, two valves remained patent and competent, whereas four valves were patent but incompetent as a result of thrombus that prevented valve closure. In group 3 all valves were patent and competent at 7, 9, and 13 days after implantation. An autogenous venous valve that opens at physiologic pressures and remains competent at high pressures can be surgically created. The ability to remain competent at high pressures may give this valve an advantage over the repaired, transposed, or transplanted native venous valve in the treatment of chronic venous valvular insufficiency.

Crush syndrome due to limb compression.

Four patients with the crush syndrome due to prolonged limb compression were treated at Cook County Hospital, Chicago. Limb injury was caused when the obtunded patient fell asleep lying on the involved extremity. Prolonged limb compression may cause an acute compartment syndrome with ischemic muscle injury. Continued muscle ischemia may lead to myonecrosis resulting in shock or renal failure. A history of prolonged limb compression with a swollen limb should suggest the diagnosis of crush syndrome. Prompt therapy, including rapid correction of volume and metabolic derangements, extensive open fasciotomy, and dialysis for severe acute renal failure should provide good functional results in the majority of patients.

Can carotid duplex scanning supplant arteriography in patients with focal carotid territory symptoms?

Previous reports have suggested that duplex ultrasonography might supplant arteriography as a guide to operative decision making in selected patients with cerebrovascular disease. This study was undertaken to test that tenet in patients with focal carotid territory symptoms. Seventy-two patients having independently interpreted arch and selective carotid arteriography and duplex scanning underwent 78 carotid endarterectomies. Operative specimens were analyzed in all cases and used as the standard in evaluating the accuracy of the preoperative studies. All patients had disease found at the time of operation. The sensitivity of duplex scanning was 99% vs. 91% for arteriography (p = 0.06). In seven cases the scan accurately predicted disease in patients with normal arteriograms and in a single case the scan was read as normal in a patient with a smooth minimally stenotic plaque read as an irregular 30% stenosis on arteriography. The accuracy of duplex scanning was markedly superior to arteriography in detecting intimal surface abnormalities (92% vs. 64%, p less than 0.001) and ulceration (90% vs. 54%, p less than 0.001). There was no difference between duplex scan and arteriography (p = 1.0) in predicting a greater or less than 50% stenosis (accuracy, 94% for arteriogram; 92% for duplex scanning). Of the patients with preoperative potentially reversible symptoms, 97% were free of symptoms at a mean follow-up of 9 months after operation. Eighty-nine percent (17 of 19 patients) of patients with concomitant, ipsilateral, intracranial, or intrathoracic cerebrovascular disease were free of symptoms after carotid endarterectomy.

Mortality and limb loss with infected infrainguinal bypass grafts.

A recent experience with infrainguinal graft infections was reviewed in an effort to identify factors related to limb loss and mortality. The records of 32 patients who had operative treatment of 33 episodes of infrainguinal graft infection between 1978 and 1985 were reviewed to evaluate the effects of 20 factors possibly affecting outcome. The amputation rate was 79%. Of the 20 factors studied, only the presence of overt limb sepsis was associated with the need for amputation, with 100% of patients having limb sepsis requiring amputation vs. 72% of patients without limb sepsis (p = 0.03). The in-hospital mortality rate was 22%. Eighty-six percent of the deaths were due to ongoing sepsis. Again, a single factor was associated with death. Five of the 12 patients (42%) in whom preservation of axial flow was attempted died in contrast to only 2 of 20 patients (10%) who did not have attempted arterial reconstruction (p = 0.04). Limb salvage did not occur in any of the patients in whom preservation of axial flow was attempted and nine required above-knee amputation. Thirteen of the remaining 20 patients had occluded femoral vessels either because of operative ligation (nine) or previous thrombosis (four). Above-knee amputations healed in all but one of these 13 patients. Determined attempts at increasing limb preservation were associated with no improvement in amputation rate or level and were accompanied by an unacceptably high mortality rate. Aggressive control of sepsis through the early amputation of septic limbs after graft removal may improve survival without further detriment to limb preservation.

Long-term follow-up of patients having infrainguinal bypass performed below stenotic but hemodynamically normal aortoiliac vessels.

Because infrainguinal bypasses performed on the basis of normal papaverine testing in patients with multilevel arterial occlusive disease are done below arteriographically diseased although hemodynamically normal vessels, there is concern about progression of suprainguinal disease compromising long-term success. This study has been done to assess the long-term results of such bypasses. Between 1979 and 1985, infrainguinal bypasses selected by papaverine testing were done on 92 limbs having hemodynamically normal inflow in the presence of arteriographically demonstrable aortoiliac stenoses of 15% to 70%. Long-term hemodynamic and clinical success rates were determined with criteria based on papaverine and noninvasive vascular testing. There was no significant difference in hemodynamic success at 48 months (by life-table analysis) (p = 0.98) when comparing limbs with less than 50% aortoiliac stenoses to limbs having 50% or greater stenoses. The difference between the mean degree of preoperative inflow stenoses for long-term hemodynamic successes (32.5% +/- 1.5%) and failures (34.6% +/- 3.0%) was not significant (p = 0.57). There was no significant difference (p = 0.98) in the number of subsequent inflow procedures required in limbs with preoperative aortoiliac stenoses of less than 50% (13.5%) vs. aortoiliac stenoses of 50% or greater (13.3%). Long-term results of infrainguinal bypass done below stenotic but hemodynamically normal aortoiliac vessels are not related to the amount of angiographically demonstrable inflow stenosis. Selection of patients for infrainguinal bypass on the basis of papaverine testing, irrespective of angiographic findings, eliminates unnecessary inflow procedures without detriment to long-term success.

The necessity of mandatory exploration of penetrating zone II neck injuries.

To reevaluate the validity of our policy of mandatory surgical exploration of penetrating zone II neck injuries, the charts of 110 patients who underwent surgical exploration for such injuries were reviewed. Fifty-three percent of the patients had normal findings at exploration, whereas 33% had injuries involving vascular structures of the neck and 14% had nonvascular injuries. Injuries were not suspected on clinical grounds preoperatively in 23% of the patients in whom surgical exploration revealed injury. The injuries most likely to escape preoperative diagnosis were isolated venous injuries and isolated pharyngoesophageal injuries. Arteriography yielded false-negative results in two arterial injuries. No deaths and only a 5% incidence of minor complications occurred in the group with no injuries detected at exploration. We conclude that surgical exploration of penetrating zone II neck injuries is safe and appropriate.

Results of venous reconstruction after civilian vascular trauma.

The treatment of venous injuries remains controversial. In an attempt to evaluate the results of current management of venous injuries, we retrospectively reviewed our experience between 1979 and 1984. During this period 142 patients had sustained injuries to 158 veins in the neck (31 patients), abdomen (45 patients), upper extremity (20 patients), and lower extremity (62 patients). Overall, 90 venous injuries (61%) were repaired, including 83% of caval and iliac vein injuries and 90% of injuries to the common femoral, superficial femoral, and popliteal veins. There was no morbidity after repair of 73 major veins. Morbidity occurred in four of 11 patients after ligation of major veins (edema in two patients and above-knee amputation in two others). Both ligation (N = 51) and repair (N = 17) of lesser veins (jugular, brachial, profunda femoral, tibial, and minor abdominal veins) resulted in no morbidity. Overall mortality was 6% with all deaths occurring in patients with abdominal venous trauma. These data indicate that repair of venous injuries can be performed without morbidity and that minor veins can be ligated without adverse sequelae. However, in view of the morbidity associated with ligation of major veins, efforts to restore flow to these injured vessels appear appropriate unless contraindicated by life-threatening injury.

Deterioration of venous function in normal lower extremities during daily activity.

The change in venous function during the course of the day was studied noninvasively in 50 normal lower extremities of 25 physically active normal subjects. Venous refilling time, measured by photoplethysmography, was significantly shorter (p less than 0.0001), and venous capacitance, measured by impedance plethysmography, was significantly reduced (p less than 0.04) after 5 hours or more of daily activities performed in the upright position. Abnormally short venous refilling time (less than 18 seconds) developed in 21% of the extremities, which had a normal venous refilling time earlier in the same day. Lower extremity symptoms of ache, pain, or swelling were reported more frequently in extremities that developed an abnormal venous refilling time. There was a trend toward a greater change in venous refilling time during the day in symptomatic lower extremities than in asymptomatic limbs (p = 0.07).

Improved results in the treatment of civilian vascular injuries associated with fractures and dislocations.

Patients with vascular injuries associated with fractures or dislocations of the extremities were managed according to a standard protocol, which included the liberal use of preoperative arteriography, early fasciotomy when indicated, individualization of timing and type of orthopedic procedures, arterial reconstruction primarily with interposition reversed saphenous vein grafts, repair of major venous injuries, routine completion arteriography, and regular postoperative monitoring of Doppler-derived ankle/brachial indices. Adherence to these principles led to a limb salvage rate of 97% in 38 patients with such injuries.

Optimal limb salvage in penetrating civilian vascular trauma.

To evaluate current treatment of peripheral vascular trauma, we reviewed our recent experience with noniatrogenic penetrating vascular injuries of the extremities. Between 1979 and 1984, 139 patients sustained 204 vascular injuries inflicted by single gunshots (64%), stabbings (24%), and shotguns (12%). Eighty-four percent of patients underwent preoperative arteriography, which revealed occult arterial injury in 13 patients (9%). Compartmental hypertension necessitated fasciotomy in 19% of patients and was required more often after combined arterial and venous injuries (29%) than after isolated arterial injury (14%). Arterial continuity was restored by interposition grafting with reversed saphenous vein (62%), end-to-end anastomosis (19%), vein patch angioplasty (8%), or primary repair (4%). After arterial repair, completion angiography detected the need for revision in 8% of patients. Arterial ligation was performed in 7% of injuries and was only used in the treatment of tibial and distal profunda femoris injuries. Forty-five percent of patients sustained concomitant venous injury; 64% of all venous injuries and 90% of femoropopliteal venous injuries were repaired. No deaths occurred, and a single patient required amputation. We conclude that a protocol of preoperative arteriography, liberal. use of fasciotomy, frequent use of autologous interposition grafts, repair of major venous injuries, and routine use of completion arteriography can result in limb salvage rates that approach 100% after penetrating vascular trauma to the extremities.