Different underlying impairments in decision-making following ventromedial and dorsolateral frontal lobe damage in humans

Ventromedial prefrontal cortex (VMF) damage can lead to impaired decision-making. This has been studied most intensively with the Iowa gambling task (IGT), a card game that asks subjects to overcome an initial attraction to high-payoff decks as losses begin to accrue. VMF subjects choose from the high risk decks more often than controls, but the fundamental impairments driving poor performance on this complex task have yet to be established. There is also conflicting evidence regarding the role of the dorsolateral prefrontal cortex (DLF) in this task. The present study examined whether poor performance on the IGT was specific for VMF damage and whether fundamental impairments in reversal learning contributed to IGT performance. We found that both VMF and DLF damage leads to impaired IGT performance. The impairment of VMF subjects, but not of DLF subjects, seems to be largely explained by an underlying reversal learning deficit.     

Noscapine suppresses angiotensin converting enzyme inhibitors-induced cough

BACKGROUND: Dry cough is a common side-effect of the angiotensin converting enzyme inhibitors (ACEI) and is a major limiting factor of their use. It has been suggested that ACEI cause this side-effect by potentiation of the bradykinin effect. Previous work in our laboratory has shown that noscapine, an antitussive drug, inhibits the effect of bradykinin. METHODS: To investigate the effect of noscapine on ACEI-induced cough, 611 hypertensive patients who were being treated with ACEI were evaluated for the incidence of persistent dry cough. RESULTS: A cough had developed in 65 (10.6%) patients, two (3.1%) of whom also had severe respiratory distress that required hospitalisation and immediate discontinuation of the ACEI. Forty-two (64.6%) patients had developed a mild cough and 21 (32.3%) patients had developed a moderate to severe cough. The patients with moderate to severe cough received 15 mg of noscapine, orally three times daily, while they continued ACEI. Noscapine effectively resolved the cough in 19 (90%) patients within 4-9 days of starting treatment. CONCLUSION: Noscapine, possibly by inhibition of bradykinin synthesis, eliminates ACEI-induced cough in the majority of patients and allows them to continue with ACEI therapy.     

Evolution of trends in risk management

In the past, the detection and response to adverse clinical events were viewed as an inherent part of professionalism; and, if perceived problems were not sorted out at that level, the ultimate expression of dissatisfaction was litigation. There are now demands for the adoption of more transparent and effective processes for risk management. Reviews of surgical practice have highlighted the presence of unacceptable levels of avoidable adverse events. This is being resolved in two ways. First, attention is being directed to the extent that training and experience have on outcomes after surgery, and both appear to be important. Second, a greater appreciation of human factors engineering has promoted a greater involvement of surgeons in processes involving teamwork and non-technical skills. The community wants surgeons who are competent and health-care systems that minimize risk. In recent times attention has been focused on the turmoil associated with change; but, when events are viewed over a period of several decades, there has been considerable progress towards these ideals. Further advancement would be aided by removing the adversarial nature of malpractice systems that have failed to maintain standards.     

Management of difficult intubation in a patient with ankylosing spondylitis--a case report

We describe a case of difficult intubation in a patient suffering from ankylosing spondylitis undergoing total hip replacement surgery. The anesthetic management of 42 year old patient with difficult airway is discussed. Failure of epidural anesthesia procedure necessitated general anesthesia. The problems of performing awake fibreoptic intubation and other alternative techniques to secure the airway are described. Cervical spine involvement in ankylosing spondylitis is of great concern for the anesthetist. Longstanding progressive course of this disease leads to fibrosis, ossification and ankylosis of entire spine and sacroiliac joints. Cervical spine mobility is decreased and in severe cases total fixity occurs in a flexed position. Patient may also have atlanto-occipital and temporo-mandibular joint involvement as well. Cricoarytenoid cartilages involvement may result in upper airway compromise. Furthermore cervical spine vertebrae are prone to fractures, especially on hyperextension and may lead to spinal cord transection and quadriplegia. In this case report we describe the airway management of such patient with fixed rigidity of cervical spine and thoracolumbar kyphosis.     

Neovascularization in acute venous thrombosis

OBJECTIVE: The aim of this study was to describe the phenomenon of arteriovenous fistula (AVF) formation in venous thrombus. METHODS: Patients referred to the vascular laboratory for evaluation for deep venous thrombosis were included. Duplex ultrasound scanning was used to detect flow within the thrombus. The flow patterns and the resistivity index were obtained in the veins above/proximal and below/distal to the thrombus, in the adjacent arteries, and within the perivenous vessels. Patients with trauma, hemodialysis access, endovenous ablation, known AVF, or inflammatory conditions were excluded. RESULTS: There were 22 patients with AVF flow in thrombosed veins. Deep veins were involved in 15 cases and superficial veins in the remainder. Perivenous vessels feeding the AVF in the thrombus could be clearly identified in 16 patients (19 vein segments). In 21 of 22 patients, multiple flow channels were present throughout the involved thrombosed vein segment. These flow channels were isolated to a single vein segment. They measured <4 cm in length in 19 cases and were more extensive in the remaining three. Reflux within the vein segment was identified in 13 cases. Local symptoms that could be attributed to the arterialization of thrombosed veins occurred in four cases, and none of the patients manifested systemic symptoms. The flow within the thrombus had high end-diastolic velocities with a mean resistivity index of 0.48 (SD, 0.08), which is typical of a fistula flow pattern. The flow in the main arteries was unaffected. CONCLUSION: Neovessels were found with AVF flow in thrombi of superficial and deep veins. They had variable length and multiple flow channels, with inflow from perivenous arteries. The flow in the adjacent main arteries was not affected, and no systemic symptoms were detected. The exact etiology and natural history of this phenomenon are not known, and its clinical significance is unclear.     

Impedance Cardiography: Noninvasive Assessment of Hemodynamics and Thoracic Fluid Content During Bariatric Surgery

Background: The effects of pneumoperitoneum (ppm) on hemodynamic parameters during bariatric surgery were investigated using the impedance cardiography monitor. Methods: 11 patients with BMI 46.5±10 kg/m² (range 38.9-60.8 kg/m²) underwent laparoscopic adjustable gastric banding under general anesthesia. Besides routine monitoring, the impedance cardiography (ICG) monitor was used to monitor cardiac output (CO), cardiac index (CI), systemic vascular resistance (SVR), and thoracic fluid content (TFC). Data were recorded at three stages: A) before ppm, B) during ppm, and C) after gas deflation. One-way analysis of variance (ANOVA) was used to analyze differences of the data before, during and after ppm, and post-hoc (Bonferoni test) for multiple comparisons of the data obtained. For all comparisons, P<0.05 was considered significant. Results: There were significant low mean values of heart rate (HR), CO and CI at stage B compared to stage A (P<0.05). The mean values of TFC at stages A, B, and C were 30.48 ± 4.69, 29.74 ± 2.86 and 31.72 ± 4.93 k/Ohm respectively, with a non-significant relationship (P>0.05). The mean values of SVR during the same stages A, B and C were 1299.18 ± 374.40, 1873.64 ± 276.26 and 1669.36 ± 537.92 dynes sec cm^-5 respectively, with significant high mean values at stages B and C compared to mean value at stage A (P<0.05). Conclusions: Morbid obesity and pneumoperitoneum have significant effects on hemodynamics. However, it appears that these changes were of marginal clinical significance.     

Laparoscopic Gastric Bypass with Silicone Band in a Pig Model: Prevention of Anastomotic Dilatation – Feasibility Study

Background: Morbid obesity has become a major global health problem. Surgery remains the only effective treatment for patients with severe obesity, because diet reduction methods and pharmacologic agents have not resulted in long-term weight reduction. Gastric bypass (GBP) can provide adequate weight loss, but after some years, dilatation of the gastric pouch and outlet may lead to weight regain by allowing the patient to increase food intake. Methods: 2 groups of 6 pigs underwent laparoscopic GBP. In the first group, a non-adjustable silicone band (Proring?-band, IOC, Innovative Obesity Care, Saint Etienne, France) was positioned 1 cm proximal to the gastrojejunal anastomosis. In the second group, the device used to stabilize the gastric pouch was an adjustable silicone band (Mid-band?, Medical Innovation Developpement, Villeurbanne, France). Weight loss, complications and histological reaction were evaluated after 3 months. Results: Mortality rate was 25% (cardiac arrythmia in 2 pigs). Conversion rate was 25%. The positioning of the band was more difficult with the Mid-band? because of its larger size and the presence of the catheter. The average weight change in the Proring? group was 15.8 kg (3.5–25.1 kg), and in the Mid-band? group was 12.0 kg (6.2–15.1 kg). Morbidity consisted of one intragastric migration of the Proring? band into the gastrojejunal anastomosis, and one infection of the port in the Mid-band? group treated by removal of the port and antibiotics. Conclusion: Use of silicone devices may be safe and effective in the prevention of pouch or outlet dilatation after GBP.     

Mucormycosis causing palatal necrosis and orbital apex syndrome

A case of mucormycosis causing palatal necrosis and orbital apex syndrome is reported successfully treated with systemic antifungal therapy, surgical debridement and control of underlying disease process. After one year of follow-up patient is blind with anatomically preserved right eye and ptosis as well as having palatal obturator. Mucormycosis should be considered in differential diagnosis of palatal necrosis and orbital apex syndrome.