Positioning patients for spine surgery: Avoiding uncommon position-related complications

Positioning patients for spine surgery is pivotal for optimal operating conditions and operative-site exposure. During spine surgery, patients are placed in positions that are not physiologic and may lead to complications. Perioperative peripheral nerve injury(PPNI) and postoperative visual loss(POVL) are rare complications related to patient positioning during spine surgery that result in significant patient disability and functional loss. PPNI is usually due to stretch or compression of the peripheral nerve. PPNI may present as a brachial plexus injury or as an isolated injury of single nerve, most commonly the ulnar nerve. Understanding the etiology, mechanism and pattern of injury with each type of nerve injury is important for the prevention of PPNI. Intraoperative neuromonitoring has been used to detect peripheral nerve conduction abnormalities indicating peripheral nerve stress under general anesthesia and to guide modification of the upper extremity position to prevent PPNI. POVL usually results in permanent visual loss. Most cases are associated with prolonged spine procedures in the prone position under general anesthesia. The most common causes of POVL after spine surgery are ischemic optic neuropathy and central retinal artery occlusion. Posterior ischemic opticneuropathy is the most common cause of POVL after spine surgery. It is important for spine surgeons to be aware of POVL and to participate in safe, collaborative perioperative care of spine patients. Proper education of perioperative staff, combined with clear communication and collaboration while positioning patients in the operating room is the best and safest approach. The prevention of uncommon complications of spine surgery depends primarily on identifying high-risk patients, proper positioning and optimal intraoperative management of physiological parameters. Modification of risk factors extrinsic to the patient may help reduce the incidence of PPNI and POVL.

Differences in characteristics of patients with and without known risk factors for hepatocellular carcinoma in the United States

AIM: To examine the clinical characteristics of a subgroup of patients with hepatocellular carcinoma (HCC) and compare them to those with known risk factors.METHODS: We used the HCC database of 306 patients seen at our institution from January 1, 1995 to December 31, 2001. Of the 306 patients, 63 (20%, group 1) had no known risk factors (hepatitis C virus, hepatitis B virus, alcohol, hemochromatosis or cirrhosis from any cause) and 243 (group 2) had one or more risk factors.RESULTS: The median age was similar in both groups, but there were disproportionate numbers of younger (< 30 years old), older (> 80 years) patients, women (33% vs 18%), and Caucasians (81% vs 52%) in group 1 as compared to group 2. There were fewer Asians (2% vs 11%) and African Americans (13% vs 27%) in group 1. Abdominal pain (70% vs 37%) was more common while gastrointestinal bleeding (0% vs 11%) and ascites (4% vs 17%) were less common in group 1 compared to group 2. Group 1 had larger tumor burden (median size 9.4 cm vs 5.7 cm) at the time of presentation, but there were no differences in the site (right, left or bilateral lesions), or number of tumors between the two groups.CONCLUSION: HCC patients without identifiable risk factors have different characteristics and clinical presentation compared to those with known risk factors.Absence of cirrhosis and larger tumor burden may explain the differences in the presenting symptoms.

Regional anesthesia for orthopedic procedures:What orthopedic surgeons need to know

Regional anesthesia is an integral component of successful orthopedic surgery.Neuraxial anesthesia is commonly used for surgical anesthesia while peripheral nerve blocks are often used for postoperative analgesia.Patient evaluation for regional anesthesia should include neurological,pulmonary,cardiovascular,and hematological assessments.Neuraxial blocks include spinal,epidural,and combined spinal epidural.Upper extremity peripheral nerve blocks include interscalene,supraclavicular,infraclavicular,and axillary.Lower extremity peripheral nerve blocks include femoral nerve block,saphenous nerve block,sciatic nerve block,iPACK block,ankle block and lumbar plexus block.The choice of regional anesthesia is a unanimous decision made by the surgeon,the anesthesiologist,and the patient based on a risk-benefit assessment.The choice of the regional block depends on patient cooperation,patient positing,operative structures,operative manipulation,tourniquet use and the impact of postoperative motor blockade on initiation of physical therapy.Regional anesthesia is safe but has an inherent risk of failure and a relatively low incidence of complications such as local anesthetic systemic toxicity(LAST),nerve injury,falls,hematoma,infection and allergic reactions.Ultrasound should be used for regional anesthesia procedures to improve the efficacy and minimize complications.LAST treatment guidelines and rescue medications(intralipid)should be readily available during the regional anesthesia administration.

肝门部胆管癌的诊断、治疗选择与处理策略

肝门部胆管癌（HC）是一种少见的疾病,通常在60岁左右发病,预后较差;在美国,每年约有3 000例患者被诊断为该病,但仅有不到一半的人可以行手术治疗;有多种因素与HC的发病有关,最常见的有原发性硬化性胆管炎（PSC）,胆石症以及寄生虫肝病。患者通常表现为腹痛、瘙痒、体质量减轻和黄疸。CT、MRI及超声可以用来发现胆道病损;逆行性胰胆管造影术（ERCP）及经皮肝胆管造影术（PTC）在评估肿块位置、长度的同时还可以行治疗性的胆汁引流。MRCP在辨别肿瘤延伸范围时同PTC及ERCP有相同的准确性,并且并发症较前两者少。HC的治疗方式主要为手术切除、放射治疗、化疗及光动力学治疗。残余肝脏胆汁引流有助于降低胆红素水平,进而促进残肝的生长;标准的治疗包括切缘为阴性切除（R0）,范围为肝外胆管切除、肝切除及周围的淋巴结清扫术;局部的切除术是不适当的;淋巴结侵犯的程度、肿瘤的级别以及切缘的性质是重要的预后指标;如果无法行肿瘤切除,那么在经反复选择后的患者中实施肝移植术也是种可行的方式;尽管数据有限,化疗对于不可切除的患者来说仍有一定的作用;经手术切除的HC患者5年生存率约为10%～40%,然而即使为R0切除,复发率也高达50%～70%。由于这种疾病的复杂性,多种学科的综合治疗是较为理想的治疗方式。