Energy Efficient H.263 Video Transmission in Power Saving Wireless LAN Infrastructure

Wireless local area networks (WLANs) are now being used in places where access point (AP) power saving would be very desirable. Although this is not currently possible, modifications to the IEEE 802.11 protocol have recently been proposed which would permit this functionality. A difficult problem that arises is to maintain good client power saving when AP power saving is introduced. This is especially true when carrying multiple real-time traffic flows such as H.263 video, where the payload size varies randomly over short time periods. In this paper, we first present protocol modifications for power saving quality-of-service (QoS) enabled access points (PSQAP). We then focus on the transmission of bursty real-time H.263 video over a PSQAP. A variety of mechanisms are proposed for this purpose, which result in various tradeoffs between station and PSQAP power saving performance. Analytical models and simulation experiments are used to assess the performance of the video scheduling algorithms. The best overall performance is obtained using a mechanism that combines a novel variant of the power save multi-poll (PSMP) protocol with a scheduling mechanism based on a discrete autoregressive video prediction model

Emergent Carotid Stent Removal after Carotid Stent Thrombosis

Background Acute carotid stent thrombosis in patients undergoing CAS is a relatively rare and potentially devastating complication influencing significantly the quality of life. With the increasing use of stenting in clinical practice, it is expected to represent a more often encountered complication for physicians performing CAS. Emergent removal of the thrombosed stent and endarterectomy is indicated when the intrastent thrombosis is not associated with intracranial carotid branch thrombosis. Methods The technique and its peculiarities and tip and tricks of this carotid operation have not been described meticulously. We describe the steps of the surgical technique in detail, and we analyze crucial issues associated with the technique. Results We have performed this emergency operation in 2 patients with acute early stroke after CAS. Both patients presented recovery of their previous neurologic deficits and had uneventful postoperative course. Conclusions We illustrate the technique of emergent removal of the thrombosed stent after CAS. If carotid stent thrombosis with no distal extension is documented post procedurally, emergency stent removal and endarterectomy is the preferred strategy. Special care should be taken to avoid risk of clot dislocation and consequent cerebral embolization during the surgical exposure of the carotid bifurcation and placement of the vascular clamps. © 2017 Elsevier Inc

A multilayer stent in the aorta may not seal the aneurysm, thereby leading to rupture

The multilayer stents are occasionally used for the treatment of complicated aortic aneurysms, including thoracoabdominal aneurysms. No aneurysm-related mortality among patients treated with this technique has been described in the literature to date. We describe a case of rupture of an aortic aneurysm previously treated with a multilayer stent. © 2012 Society for Vascular Surgery

A Technical Tip of Aortic Stump Reinforcement with Plication of the Falciform Ligament of the Liver

Background: The residual stump after excision of an infected aortic graft may be subject to acute disruption—blowout—because of recurrence of infection or fatigue due to the mechanical stress. We present an innovative technique in which we used the falciform ligament of the liver to reinforce the aortic stump. Methods: We excised the falciform ligament by giving attention to avoid any bleeding from the liver. The aortic stump was reinforced with synthetic, monofilament, nonabsorbable polypropylene sutures and the falciform ligament of the liver was plicated inside the stump and further sutured with polypropylene sutures. Results: After 5 months, he is in excellent condition. His laboratory examination is normal, he has stopped taking antibiotics, gained his initial weight, and recovered full activity. Conclusions: We presented an innovative technique in which we used the falciform ligament of the liver to reinforce the aortic stump after excision of an infected aortobiiliac synthetic graft. This technique can be an alternative option in patients with weak arterial wall or extended bacterial local infection in the retroperitoneal area which renders the aortic wall tissue extremely stiff to be folded and sutured. This technique may enhance the mechanical integrity of the stump. © 2020 Elsevier Inc

Open Repair of a Ruptured Abdominal Aortic Aneurysm on a Patient Under Rivaroxaban and Clopidogrel

Background: Direct oral anticoagulants are commonly used instead of vitamin K antagonists in patients needing long-term anticoagulant treatment. As their use has become more popular, there is an increase possibility to perform a major surgery on an urgent or emergency basis on patients under nonvitamin–K antagonist oral anticoagulants. Case report: We report a case of a ruptured abdominal aortic aneurysm on a male patient under rivaroxaban and clopidogrel. Emergency open repair of the aneurysm was performed. No anti-Xa antidote was administered. The patient had an uneventful recovery. Conclusion: An open repair of a ruptured abdominal aortic aneurysm under rivaroxaban is feasible. However, an antidote should be available in cases of uncontrolled diffused bleeding. To the best of our knowledge, this is the first reported case of successful open repair of a ruptured abdominal aortic aneurysm on a patient under rivaroxaban and clopidogrel. © 201