Protective Effect of Posterior Cerebral Circulation on Carotid Body Ischemia

Summary. Summary.   Background and Purpose: Carotid Bodies (CB) are fed mainly by External Carotid Artery (ECA) and rarely by Internal Carotid Artery (ICA). We aimed to investigate the effect of Bilateral Common Carotid Artery ligation and BCCAL plus bilateral external carotid artery ligation on CB.   Methods: This study has been conducted on 30 hybrid male rabbits. Normal CB analyses were made in six of these animals and others divided into two groups. BCCAL has been applied to the 1st group, and the 2nd group has undergone bilateral ECA ligation in addition to BCCAL. After sacrificing the animals, both sides CB were histopathologically observed. Normal and ischemic cells were counted.   Findings: Bilateral Common Carotid Artery ligation did not cause total atrophy in CB. Partial reversible atrophy of CB was seen in group I, but that atrophy was found to be irreversible and all animals died within one week after ligation in group II.   Interpretation: Retrograde blood flow mechanisms and collateral circulation impede the oligemic CB atrophy after BCCAL. But bilateral ECA ligation, in addition to BCCAL, causes both sides irreversible CB atrophy and death of animals within one week of ligation.   Abstract: The CB are parasympathetic paraganglia. They are chemoreceptors and located at the bifurcation zone of common carotid arteries. They are fed mainly by ECA or by its branches and rarely by ICA. As a consequence of this, BCCAL and/or ligation of external branches of common carotid artery may lead to an ischemic impairment of CB. In order to analyse the effect of carotid stenosis on CB, CB were directly examined in 6 of 30 hybrid rabbits. BCCAL was applied to twelve rabbits (group I) with ligation of both ECA in addition to BCCAL were made to the others (group II). Animals were followed up four months in group I; but all of the animals in group II died within one week. From both sides the CB were taken including the carotid bifurcation and histopathological changes were evaluated. As a result, it has been observed that incomplete ischemic lesions have developed in the CB because of retrograde blood flow from posterior circulation to the ECA providing blood for the CB. But in the second group these changes were irreversible and on both sides CB complete atrophy developed in those whose ECA were also ligated bilaterally.     

The Independent Effect of Propofol Anesthesia on Whole Body Protein Metabolism in Humans

Background: The purpose of this study was to examine the effect of general anesthesia with propofol in the absence of surgical stimulation on whole body protein metabolism.

Methods: Six unpremedicated patients were studied. General anesthesia included propofol (120 [micro sign]g [middle dot] kg-1 [middle dot] min (-1)), vecuronium bromide, and oxygen-enriched air. Changes in protein breakdown, protein oxidation, and synthesis were measured by an isotope dilution technique using a constant infusion of the stable isotope tracer L-[1-(13) C]leucine (0.008 mg [middle dot] kg-1 [middle dot] min-1) before and during 100 min of propofol anesthesia. The plasma concentrations of glucose, lactate, non-esterified fatty acids, and cortisol were measured before and during anesthesia.

Results: An isotopic steady state of plasma [1-(13) C] [Greek small letter alpha]-ketoisocaproate (taken to represent the intracellular leucine precursor pool enrichment for protein synthesis) and expired13 C-carbon dioxide were obtained before and during propofol infusion. Whole body protein breakdown decreased during propofol anesthesia by 6% (P < 0.05), whereas protein synthesis and oxidation did not change significantly. Plasma concentration of cortisol decreased after 90 min of propofol anesthesia (P < 0.05). No significant changes of plasma concentrations of glucose, lactate, and non-esterified fatty acids occurred during propofol administration.     

Permanent Preoperative Carotid Artery Occlusion and Carotid Body Tumor Surgery

Precise angiographic evaluation of the cerebrovascular system and radiographically controlled balloon occlusion of the internal carotid artery have considerably changed the risk involved with carotid surgery at the skull base. Preoperative permanent balloon occlusion of the internal carotid artery was used in three patients with infiltrative carotid body tumors. Embolization and definitive preoperative control of the carotid artery provided ideal conditions for focusing the surgeon's attention on radical removal of tumor with maximal functional preservation of the adjacent cranial nerves.     

颈动脉体瘤的诊断和治疗

目的总结颈动脉体瘤的诊治经验,探讨颈动脉体瘤的诊断、术前准备、手术方法和并发症的防治。方法10例颈动脉体瘤患者,5例首诊时误诊为其他疾病。3例术前行数字减影血管造影检查,9例行B超检查,1例行ECT检查,5例行CT检查,3例行MRI检查,2例行脑血流图检查,仅3例手术前行颈动脉压迫试验。7例采用单纯瘤体切除,1例行瘤体与颈外动脉切除,1例行瘤体与部分颈总动脉、分叉及颈内、外动脉一同切除,未做颈动脉重建,1例瘤体切除同时行部分颈总动脉、分叉及颈内、外动脉切除,并行自体大隐静脉移植术。结果本组术后无死亡、偏瘫和失明病例,1例出现患侧口角歪斜,2例出现霍纳综合征,2例出现声嘶、呛咳,2例出现吞咽困难,3例出现舌歪。9例获随访,时间1～12年,无复发病例。结论临床医师应提高对颈动脉体瘤的认识,注意选择合适的检查方法以免误诊 充分的术前准备、良好的肿瘤暴露和手术技巧、精心的术后护理是治愈该病、预防并发症的关键。     

颈动脉体瘤68例报告

目的:探讨颈动脉体瘤外科手术的经验.方法:总结1962年至1998年收治68例颈动脉体瘤,其中34例(50%)行单纯瘤体剥除,13例(19.1%)行瘤体连同包绕的颈外动脉一并切除,21例(30.9%)行瘤体及包裹的颈内动脉、颈总动脉分叉切除,在这21例中行颈内动脉重建的有18例,颈总动脉或颈内动脉结扎的有3例.结果:手术死亡2例,死亡率为2.9%.术后发生脑梗塞4例.术后并发症中以神经麻痹最多见,共有26例,其中舌下神经15例,迷走神经主干7例,迷走神经分支如咽支、喉上神经等9例,面神经下颌支1例,交感神经8例.结论:颈动脉体瘤因其解剖上的特殊性,使手术有一定的难度.随着手术技术和麻醉方法的改进,颈动脉体瘤手术变得更安全,但术后神经损伤的并发症仍较难控制.     

Surgical Management of Carotid Body Tumors

Background  Carotid body tumors (CBT) should be considered when evaluating every lateral neck mass. Methods  A retrospective study was conducted of 52 patients with 57 CBT. The surgical approach and complications were reviewed. All patients were operated on without preoperative embolization. Results  Multifocal paraganglioma (PG) were detected in six cases. A succinate dehydrogenase subunit D (SDHD) mutation was discovered in four patients. Vascular peroperative complication occurred in one case. Vascular reconstruction was decided peroperatively in five cases (8.8%). Vascular reconstruction was 0% for Shamblin 1 or 2 tumors, but 28.5% for Shamblin 3. A postoperative nerve paresis was reported in 24 patients (42.1%) and vagal nerve paralysis persisted in four cases (7.01%). The rate of serious complications, e.g., permanent nerve palsy, preoperative and postoperative complications, was 14.03%; it was 2.3% for Shamblin 1 or 2 tumors and 35.7% for Shamblin 3. One patient had malignant PG with node metastasis and was not referred for radiotherapy. No recurrence or metastasis was reported after 6-year follow-up. Conclusion  Early surgical treatment is recommended in almost all patients after preoperative evaluation and detection of multifocal tumors. Surgical excision of small tumors was safe and without complication, but resection of Shamblin 3 tumors can be challenging. Routine preoperative embolization of carotid body paragangliomas is not required.     

对侧颈动脉切除后的颈动脉体瘤手术

目的 探讨对侧颈动脉已被切除的颈动脉体瘤的手术方法.方法 左颈动脉体瘤患者1例,女,54岁.右侧颈动脉31年前因右颈动脉体瘤手术已经切除,本次手术以成对的蚊式钳逐步直接分离至瘤体与颈内动脉的Gorldon-Tayler白线,在保证颈内动脉完整的情况下,完整切除瘤体及包裹其内的颈外动脉.结果 患者术后无声音嘶哑、呛咳、头晕等并发症,顺利出院.结论 充分的术前准备及正确的分离平面是保证手术顺利的关键.     

颈动脉体瘤的诊断与手术治疗

目的总结颈动脉体瘤的诊断和外科手术治疗的经验。方法分析我院1991年9月至2009年2月期间手术治疗的16例颈动脉体瘤患者的临床资料。结果术前均行彩色多普勒超声检查,9例行CT检查,6例行数字减影血管造影检查。3例首诊时误诊为其他疾病。11例行单纯瘤体切除;5例采用大隐静脉行颈动脉重建。术后1例出现声音嘶哑,1例出现伸舌右偏,1例出现呼吸困难。10例获得7个月～15年(平均67个月)随访,未见复发和转移。结论临床医师应提高对颈动脉体瘤的认识,注意选择合适的检查方法以免误诊,外科手术切除是首选的治疗措施,大隐静脉重建颈动脉是一种较安全、有效的治疗方法。     

Immunohistochemical Characteristics of Canine Aortic and Carotid Body Tumours

In an immunohistochemical study of 25 canine chemodectomas, 17 tumours were stained with antisera to neurone specific enolase and the same number were stained for synaptophysin; a single tumour was stained for S100. Staining for Ki‐67 occurred in 18 cases; the Ki‐67‐labelling index and the intensity of immunostaining was increased in more pleomorphic and malignant tumours, as assessed on histological grounds. Immunohistochemistry did not aid in recognition of less well‐differentiated tumours.     

瑞马唑仑结合丙泊酚方案对鼻整形患者围手术期体动及呼吸抑制情况的影响

目的 观察对鼻整形患者应用瑞马唑仑结合丙泊酚方案的效果及对围手术期体动及呼吸抑制情况 的影响。方法 选取2022年6月-2024年2月南皮县人民医院收治的88例鼻整形患者,根据信封法分为对照 组和观察组,每组44例。对照组采用丙泊酚麻醉方案,观察组采用瑞马唑仑结合丙泊酚麻醉方案。比较两 组麻醉前（T0）、麻醉10 min后（T1）、麻醉40 min后（T2）生命体征变化[心率（HR）、收缩压（SBP）、 舒张压（DBP）]、麻醉效果（麻醉时间、苏醒时间、离开监测室时间）、镇痛质量（VAS评分）、呼吸 抑制情况（呼吸频率、呼吸道梗阻）及体动情况。结果 两组T0期间HR、SBP以及DBP比较,差异无统 计学意义（P ＞0.05）,而观察组T1、T2期间HR、SBP以及DBP水平优于对照组（P ＜0.05）。观察组麻 醉时间、苏醒时间、离开监测室时间短于对照组（P ＜0.05）。观察组术后3、12、24 h的VAS评分均低 于对照组（P ＜0.05）。观察组麻醉1 min后呼吸频率高于对照组,呼吸道梗阻人数低于对照组（P＜0.05）。观 察组体动发生率为4.55%,低于对照组的9.09%,但差异无统计学意义（P＞0.05）。结论 相较于单一应用丙 泊酚,配合应用瑞马唑仑安全系数相对更高,且对呼吸质量较好,麻醉效果确切。     

A Randomized Crossover Comparison of the Effects of Propofol and Sevoflurane on Cerebral Hemodynamics during Carotid Endarterectomy

Background: Intravenous and inhalational anesthetic agents have differing effects on cerebral hemodynamics: Sevoflurane causes some vasodilation, whereas propofol does not. The authors hypothesized that these differences affect internal carotid artery pressure (ICAP) and the apparent zero flow pressure (critical closing pressure) during carotid endarterectomy. Vasodilation is expected to increase blood flow, reduce ICAP, and reduce apparent zero flow pressure.

Methods: In a randomized crossover study, the gradient between systemic arterial pressure and ICAP during carotid clamping was measured while changing between sevoflurane and propofol in 32 patients. Middle cerebral artery blood velocity, recorded by transcranial Doppler, and ICAP waveforms were analyzed to determine the apparent zero flow pressure.

Results: ICAP increased when changing from sevoflurane to propofol, causing the mean gradient between arterial pressure and ICAP to decrease by 10 mmHg (95% confidence interval, 6-14 mmHg; P < 0.0001). Changing from propofol to sevoflurane had the opposite effect: The pressure gradient increased by 5 mmHg (95% confidence interval, 2-7 mmHg; P = 0.002). Ipsilateral middle cerebral artery blood velocity decreased when changing from sevoflurane to propofol. Cerebral steal was detected in one patient after changing from propofol to sevoflurane. The apparent zero flow pressure (mean +/- SD) was 22 +/- 10 mmHg with sevoflurane and 30 +/- 14 mmHg with propofol (P < 0.01). There was incomplete drug crossover due to the limited duration of carotid clamping.     

Involvement of the Basal Cholinergic Forebrain in the Mediation of General (Propofol) Anesthesia

Background: Recent studies have pointed out the involvement of the basal forebrain [gamma]-aminobutyric acid-mediated system in mediating the effects of general anesthesia. In this study, the authors asked whether the basal forebrain cholinergic system is also involved in mediating the effects of general anesthetics such as propofol.

Methods: Cholinergic lesions were produced by administration of the selective immunotoxin 192 immunoglobulin G-saporin into the lateral ventricles, the medial septum, or the nucleus basalis magnocellularis. The anesthetic potency of propofol was determined using an anesthetic score with a crossover counterbalanced design. Animals were given intraperitoneal propofol (25 or 50 mg/kg) repeatedly every 15 min to set up a subanesthetic (low-dose) or anesthetic (high-dose) state. The anesthetic score was assessed for each cumulative dose. Control of the cholinergic depletion was performed using histochemical acetylcholinesterase staining on brain slices.

Results: A shift from a subanesthetic state to an anesthetic state was observed mainly in the rats with the immunotoxin injected into the lateral ventricles or the medial septum and vertical diagonal band of Broca, compared with controls. In those rats, the density of acetylcholinesterase reaction products was normal in the striatum and the thalamus, but reduced in the cortex and the hippocampus.