[Skeletal muscle ischemia-reperfusion and ischemic conditioning pathophysiology-clinical applications for the vascular surgeon]. / Physiopathologie de l'ischémie-reperfusion et du conditionnement ischémique du muscle squelettique ­ applications cliniques pour le chirurgien vasculaire.

Ischemia-reperfusion, which is characterized by deficient oxygen supply and subsequent restoration of blood flow, can cause irreversible damage to tissue. The vascular surgeon is daily faced with ischemia-reperfusion situations. Indeed, arterial clamping induces ischemia, followed by reperfusion when declamping. Mechanisms underlying ischemia-reperfusion injury are complex and multifactorial. Increases in cellular calcium and reactive oxygen species, initiated during ischemia and then amplified upon reperfusion are thought to be the main mediators of reperfusion injury. Mitochondrial dysfunction also plays an important role. Extensive research has focused on increasing skeletal muscle tolerance to ischemia-reperfusion injury, especially through the use of ischemic conditioning strategies. The purpose of this review is to focus on the cellular responses associated with ischemia-reperfusion, as well as to discuss the effects of ischemic conditioning strategies. This would help the vascular surgeon in daily practice, in order to try to improve surgical outcome in the setting of ischemia-reperfusion.

[Persistent or recurrent hyperparathyroidism in periodically hemodialyzed patients. Value of preoperative cervical ultrasonography. 6 cases]. / Hyperparathyroïdies persistantes ou récurrentes des hémodialysés périodiques. Intérêt de l'échographie cervicale préopératoire. Six observations.

In 2 cases of recurrent secondary hyperparathyroidism and 4 cases of persisting secondary hyperparathyroidism observed in patients treated by chronic haemodialysis, 8 hyperplastic parathyroid masses and 1 parathyroid adenoma, all located in the lower part of the neck, were removed after percutaneous ultrasonographic detection. There were 7 true positive and 1 unexplained false positive results. In 1 out of the 2 false negative results, the mass located behind the esophagus could not be detected because of the laryngotracheal gas. Two masses located inside the thyroid gland and a 5th hyperplastic gland were correctly identified by ultrasound. Two reluctant patients accepted a new cervicotomy because of the ultrasound reports. The reports played a prominent role in the operative technique in 3 cases.