Use of arm veins for lower extremity arterial bypass--results, anatomical features and technical considerations.

Forty lower limb bypasses using arm veins were performed on 37 patients. The indications for surgery were limb threat in 50% of cases, graft failure in 33%, aneurysms in 10% and claudication in 7%. Saphenous veins were absent because of prior use in 73% of cases, and because they were unsuitable in 27%. A single vein was used in 48%, 2 veins in 40% and 3 veins in 12% of cases. Seventy-four per cent of cases had a single-vessel run-off below the distal anastomosis. Eighty-two per cent of the distal anastomoses were to infrapopliteal arteries. The primary and secondary rates of these 40 bypasses at a mean follow-up of 14 months (range 1-40 months) were 74% and 90%, respectively. Limb salvage was 94%. Peri-operative morbidity and mortality were 23% and 3%, respectively. The anatomical and technical aspects of harvesting arm veins are critical to the success of this procedure and will be emphasised. We have found arm veins to be a durable source of accessible autogenous grafts for lower limb revascularisation in the absence of suitable saphenous veins.

Transcranial Doppler intraoperative monitoring during carotid endarterectomy: experience with regional or general anesthesia, with and without shunting.

To determine whether continuous transcranial Doppler (TCD) can significantly alter therapeutic conduct during carotid endarterectomy, a retrospective study of 117 carotid endarterectomies was done. There was no perioperative mortality; one perioperative stroke was recorded in a patient who was symptomatic preoperatively. Continuous TCD of the ipsilateral middle cerebral artery (MCA) was attempted in 99 cases, and successful in 90; nine patients (9.1%) had inadequate temporal windows for MCA access. MCA velocities and emboli were recorded before and during carotid cross-clamping, and on clamp release. There were no significant velocity differences between the patients with regional and general anesthesia, and patients with and without carotid shunts, but there was a statistically significant difference in the total number of emboli (air and particulate transients) noted for the shunted and nonshunted patients after clamp release: 12.7 versus 23.6, respectively (p = 0.05). There was no significant difference when particulate and air microemboli were compared. During surgery TCD identified residual flow of less than 40% in the MCA in 17 patients (18.8%). TCD also identified hyperperfusion in two patients, shunt abnormalities in three patients, and influenced postop treatment in four patients, one of whom was returned to surgery. TCD is an important tool for identifying patients who would benefit from a shunt, preventing hyperperfusion, identifying postop emboli, and detecting technical errors.