[TAVI simplification: A focus]. / Simplification des procédures TAVI : mise au point.

After a first procedure carried out in 2002 by Pr Cribier's, Transcatheter Aortic Valve Replacement or TAVR revolutionized the management of aortic stenosis with a constant increase in the number of procedures performed worldwide. Experience of operators and teams and evolution of the technique has been accompanied by a drastic reduction in complications in patients at lower surgical risk. In parallel, the procedure was considerably simplified, carried out more and more under local anesthesia, with percutaneous femoral approach, secondary radial approach, prosthesis implantation without predilatation, rapid pacing on left ventricle wire and early discharge. Thus, the "simplified" TAVR adopted in most centers nowadays is a real revolution of the technique. However, simplified TAVR must be accompanied upstream by a rigorous selection of patients who can benefit from a minimalist procedure in order to guarantee its safety.

Comparative Induction of Controlled Hypotension by Electroacupuncture at DU20 Acupoint and Remifentanil in Lumbar Laminectomy.

Hypotensive anesthesia is utilized to reduce bleeding during orthopedic surgery. One of the various drugs that have been used to reduce blood pressure is remifentanil. This study was an attempt to compare the effect of remifentanil with that of electroacupuncture (EA) at DU20 on reducing blood pressure. In this randomized controlled clinical trial, 54 patients undergoing lumbar laminectomy were allocated to two groups. Hypotensive anesthesia was performed through infusion of remifentanil 100 µg/kg/min for the control group, and EA at DU20 acupoint with a frequency of 2-10 Hz and intensity of 1-5 mA for the intervention group. Blood pressure, pulse rate, volume of blood lost and the quality of surgical field were evaluated every 10 min. There were no statistically significant differences between the two groups in terms of the changes in mean arterial pressure (MAP), pulse rate, and the quality of surgical field (P > 0.05). Therefore, EA can be as effective as remifentanil to reduce blood pressure in the patients undergoing lumbar laminectomy.

[Effects of the renal blood flow at different levels by transcutaneous electrical acupoint stimulation combined general anesthesia induced controlled hypotension].

OBJECTIVE: To observe the intervention of transcutaneous electrical acupoint stimulation (TEAS) on the renal blood flow at different levels of mean arterial pressure (MAP) in controlled hypotension. METHODS: Forty-two male beagle dogs were randomly divided into seven groups, i. e., the general anesthesia group, the 50% controlled group, the 40% controlled group, the 30% controlled group, the 50% experimental group, the 40% experimental group, and the 30% experimental group, 6 in each group. Beagles in the general anesthesia group were not treated with controlled hypotension, and the target MAP was achieved in those of the rest groups and maintained for 60 min. In the experimental groups, TEAS was applied to bilateral Hegu (LI4), Zusanli (ST36), Sanyinjiao (SP6), and Quchi (LI11) at 2/100 Hz with the stimulation strength of (4 +/- 1) mA starting from the stability of their physiological conditions to 60 min of maintaining the target MAP level. The changes of the renal blood flow were monitored at different time points using laser Doppler. RESULTS: From starting pressure control to the target MAP level, the renal blood flow was significantly lower in the 30% controlled group than in the general anesthesia group and the basic level of the same group (P < 0.05), while there was no obvious change in the 30% experimental group. In maintaining the blood pressure, the renal blood flow was significantly lower in the 50% controlled group, the 40% controlled group, the 30% controlled group, and the 30% experimental group than in the general anesthesia group (P < 0.05), while there was no obvious change in the 50% experimental group or the 40% experimental group. By the end of blood pressure recovery, the renal blood flow restored to the basic level in the 50% controlled group, the 50% experimental group, and the 40% experimental group (P > 0.05), while it was not restored to the basic level in the 40% controlled group, the 30% controlled group, and the 30% experimental group (P < 0.05). CONCLUSION: TEAS combined general anesthesia in controlled hypotension could effectively improve the renal blood flow, thus protecting the kidney.

Effects of the preoperative administration of Yunnan Baiyao capsules on intraoperative blood loss in bimaxillary orthognathic surgery: a prospective, randomized, double-blind, placebo-controlled study.

Yunnan Baiyao is a well-known Chinese herbal medicine that has been used as a haemostatic drug for nearly 100 years. The aim of this clinical trial was to evaluate the efficacy and safety of Yunan Baiyao capsules on the reduction of blood loss in bimaxillary orthognathic surgery. 87 consecutive patients scheduled for simultaneous maxillary Le Fort I osteotomies and bilateral sagittal split ramus osteotomies (BSSRO) were enrolled in a prospective, randomized, double-blind, placebo-controlled clinical trial. Patients were administered Yunnan Baiyao capsules or placebo capsules, orally for 3 days before surgery. Intraoperative blood loss was estimated and the safety of Yunnan Baiyao capsules was evaluated. The total blood loss in the Yunnan Baiyao group (mean, 330.5+/-134.4 ml) was significantly lower than in the control group (mean, 420.3+/-175.9 ml). No allergic reactions, thromboembolic events or other side effects were recorded in this trial. It can be concluded that the preoperative use of Yunnan Baiyao capsules, in combination with hypotension anaesthesia, results in a reduction in intraoperative blood loss in bimaxillary orthognathic surgery. Yunnan Baiyao capsules are an effective and safe haemostatic Chinese medicine.

Controlled hypotension: a guide to drug choice.

For half a century, controlled hypotension has been used to reduce bleeding and the need for blood transfusions, and provide a satisfactory bloodless surgical field. It has been indicated in oromaxillofacial surgery (mandibular osteotomy, facial repair), endoscopic sinus or middle ear microsurgery, spinal surgery and other neurosurgery (aneurysm), major orthopaedic surgery (hip or knee replacement, spinal), prostatectomy, cardiovascular surgery and liver transplant surgery. Controlled hypotension is defined as a reduction of the systolic blood pressure to 80-90 mm Hg, a reduction of mean arterial pressure (MAP) to 50-65 mm Hg or a 30% reduction of baseline MAP. Pharmacological agents used for controlled hypotension include those agents that can be used successfully alone and those that are used adjunctively to limit dosage requirements and, therefore, the adverse effects of the other agents. Agents used successfully alone include inhalation anaesthetics, sodium nitroprusside, nitroglycerin, trimethaphan camsilate, alprostadil (prostaglandin E1), adenosine, remifentanil, and agents used in spinal anaesthesia. Agents that can be used alone or in combination include calcium channel antagonists (e.g. nicardipine), beta-adrenoceptor antagonists (beta-blockers) [e.g. propranolol, esmolol] and fenoldopam. Agents that are mainly used adjunctively include ACE inhibitors and clonidine. New agents and techniques have been recently evaluated for their ability to induce effective hypotension without impairing the perfusion of vital organs. This development has been aided by new knowledge on the physiology of peripheral microcirculatory regulation. Apart from the adverse effects of major hypotension on the perfusion of vital organs, potent hypotensive agents have their own adverse effects depending on their concentration, which can be reduced by adjuvant treatment. Care with use limits the major risks of these agents in controlled hypotension; risks that are generally less important than those of transfusion or alternatives to transfusion. New hypotensive drugs, such as fenoldopam, adenosine and alprostadil, are currently being evaluated; however, they have disadvantages and a high treatment cost that limits their development in this indication. New techniques of controlled hypotension subscribe to the use of the natural hypotensive effect of the anaesthetic drug with regard to the definition of the ideal hypotensive agent. It must be easy to administer, have a short onset time, an effect that disappears quickly when administration is discontinued, a rapid elimination without toxic metabolites, negligible effects on vital organs, and a predictable and dose-dependent effect. Inhalation agents (isoflurane, sevoflurane) provide the benefit of being hypnotic and hypotensive agents at clinical concentrations, and are used alone or in combination with adjuvant agents to limit tachycardia and rebound hypertension, for example, inhibitors of the autonomic nervous system (clonidine, beta-blockers) or ACE inhibitors. When they are used alone, inhalation anaesthetics require high concentrations for a significant reduction in bleeding that can lead to hepatic or renal injury. The greatest efficacy and ease-of-use to toxicity ratio is for techniques of anaesthesia that associate analgesia and hypotension at clinical concentrations without the need for potent hypotensive agents. The first and oldest technique is epidural anaesthesia, but depending on the surgery, it is not always appropriate. The most recent satisfactory technique is a combination treatment of remifentanil with either propofol or an inhalation agent (isoflurane, desflurane or sevoflurane) at clinical concentrations. In light of the current literature, and because of their safety and ease of use, these two techniques are preferred.

Strategies for minimizing blood loss in orthopedic surgery.

Several major orthopedic surgical procedures including hip arthroplasty, femoral osteotomy, and spinal fusion may result in significant blood loss and the need for allogeneic blood transfusions. Due to the heightened awareness of the potential deleterious effects of allogeneic blood product administration, several techniques have been evaluated to determine their efficacy in limiting perioperative blood loss. The following article will discuss the options to limit the need for allogeneic blood product administration during orthopedic surgical procedures. These techniques include: general considerations, autologous transfusion therapy, intraoperative and postoperative blood salvage, pharmacologic manipulation of the coagulation cascade, and controlled hypotension. Undoubtedly, many of these techniques are effective alone; however, the goal of performing major orthopedic surgical procedures without the use of allogeneic blood products can only be accomplished by combining several of these techniques.

[Clinical application of combined acupuncture-drug anesthesia with isoflurane-induced hypotension in cerebral operation].

OBJECTIVE: To evaluate the feasibility of combined acupuncture-isoflurane anesthesia with deliberated and controlled hypotension induced by isoflurane for the neurosurgical patients. METHODS: Forty-two patients with brain tumor scheduled for selective surgery according to the methods of anesthesia, they were further divided into isoflurane anesthesia (group I, n = 21) and combined acupuncture-isoflurane anesthesia (group II, n = 21). Anesthesia was induced with fentanyl, sodium pentothal and phi avolon intravenously administered. The concentration of isoflurane was elevated to reduce mean arterial pressure (MAP) 30%-40% during dissection and occlusion of the tumor. Compare with the hemodynamic parameters (CO, CI, SV, SI, SVR, LVSWI, RPP) which were measured with Swan-Ganz technique before, during and after isoflurane-induced hypotension. In group II, during tracheal intubation the acupoint of Quanliano (SI 18), Yuyao (EX-HN4), Fengchi (GB 20) and Hegu (LI 4) were stimulated by Han's Acupoint Nerve Stimulator. Meanwhile, the isoflurane was inhalated to maintain anesthesia. RESULTS: As compared with group I, concentration of isoflurane decreased significantly, and isoflurane average dosage per hour reduced by 31%-42% in group II. SVR, PVR, RPP were significantly decreased in the duration of hypotension (P < 0.05). The range change of CO, CI, SV, SI, LVSWI, RPP during controlled hypotension was significantly lower in combined acupuncture-isoflurane anesthesia than that in isoflurane anesthesia (P < 0.05). CONCLUSION: Combined acupuncture-isoflurane anesthesia with isoflurane induced hypotension was used as a selective way for deliberated and controlled hypotension to the neurosurgical patients.

[Controlled hypotension against a background of nimodipine during an operation on neurosurgical patients with hypertension]. / Kontrolirana khipotoniia na fona na nimodipin pri operirane na nevrokhirurgichno bolni s khipertoniia.

Operative interventions in subarachnoid hemorrhages caused by brain vessel aneurysm require meticulous dissection of the latter. Regardless of the preoperative preparation of hypertensives, hypertension is a factor predisposing to intraoperative blood pressure fluctuation which, in turn, is extremely unfavourable and interferes with the operation proper on the aneurysm. What is more, it augments the spasm of cerebral vessels and brain edema. Any increase in blood pressure may result in a rupture of the aneurysm. As shown by a parallel study on two groups of patients with hypertension, following intraoperative administration of calcium antagonists having a preventive effect on brain, the stabilization of blood pressure attained is persistent, with the spasm of cerebral vessels and brain edema lending themselves more readily to control. The application of controlled hypotension is more easily effected, and administration of ganglioblocking agents is unnecessary.

[Conservation of the blood]. / La conservation du sang

Many factors already contribute to limit the amount of bank blood available for therapeutic use; a possible reduction in the amount of available blood could stem from the relative indifference of young people towards the gift of blood and the increase in the size of the pool of positive carriers of Australian antigen. Moreover, new operations appear (coronary by-pass) which increase the demand for blood. It is imperative that we adopt attitudes and practice techniques that will contribute to the conservation of blood. This paper discusses the advantages of an active blood bank committee which, alone, can reduce the consumption of blood by 20 percent. Moreover, actual techniques for conservation of blood are reviewed: controlled hypotension, haemodilution and intraoperative blood salvage.