Radiofrequency-assisted liver resection

BACKGROUND: Surgical resection remains the treatment of choice for primary, secondary liver cancer and a number of benign liver lesions. Complications are mainly related to blood loss. Radiofrequency-assisted liver resection (RF-LR) has been proposed in order to achieve minimal blood loss during parenchymal transection. PATIENTS AND METHODS: Between May 2005 and April 2007, 46 consecutive patients with various hepatic lesions underwent RF-LR using Radionics, Cool-Tip System. There were 28 men and 18 women with median age 65 years (range 54-76 years). Twelve major and 34 minor hepatectomies were performed for various diseases: hepatocellular carcinoma (n=19), metastatic carcinoma (n=23), focal nodal hyperplasia (n=2) and intrahepatic cholangiocarcinoma (ICC) (n=2). Hepatic inflow occlusion was not used. RESULTS: No perioperative death was documented. Median blood loss was 100ml (range 30-300cm(3)). Blood transfusion was required postoperatively in one patient. Median transection time was 35min (15-60min). Three patients developed biliary fistulas, four patients pleural effusions, one patient hyperbilirubinemia, two pneumonia and four wound infection. The median postoperative hospital stay was 6 days (range 4-10 days). In a median 12 month follow-up (range 3-24 months), four patients with colorectal metastases (CRM) and one patient with ICC developed recurrence. CONCLUSIONS: Cool-Tip RF device provides a unique, simple and safe method of bloodless liver resections and is indicated in cirrhotic patients with challenging hepatectomies (segment VIII, central resections).     

Pandemic Preparedness in Animal Facilities

Coping ethically with dramatic changes such as those occurring in times of pandemics is a difficult challenge for animal facilities and for researchers using animals for scientific purposes. Managing such situations is impossible without a specific contingency plan. However, because pandemics are rare events, they have not been included in some disaster plans. We present here various ways to manage the broad and rapid changes that may be necessary during a pandemic, focusing on actions for optimizing the conservation of animals while ensuring continuous high standards of animal welfare. The proposed approach is graduated and encompasses research, researchers, animal caretakers, supply chains, and logistics.

On 31 December 2019, the first suspected cases of an epidemic of viral pneumonia, determined as severe acute respiratory syndrome, of unknown etiology was reported in Wuhan, China.⁸ The pathogen is a new virus from the Coronaviridae family, SARS-CoV-2,¹⁴ and is responsible for the infectious respiratory disease known as COVID-19.¹³ As of the end of April 2020, half of the people on earth were confined at home, resulting in a novel dramatic social and economic crisis that affects all parts of our society, including animal facility activities.The origin and reservoir for SARS-CoV-2 was probably an animal, and even though SARS-CoV-2 is very close to a virus found in a bat,³ the species underlying transmission of the virus to humans has not yet been definitively identified. No scientific evidence to date suggests that pets or and livestock contribute to the spread of the SARS-CoV-2 virus, even though some pets have become infected, and some get ill.^6,12 Nonetheless, the virus raises several concerns for most animal facilities in regard to animal-to-human transmission and animal health.Activities in animal facilities have been and remain highly disturbed by this pandemic, mainly because of personnel unavailability, forced termination of procedures (because researchers and technicians cannot reach the facilities), and potential shipment delays. Plans for continuing critical functions, mainly providing animal care and the breeding of noncommercially available lines, should be implemented according to an animal resource contingency plan. Depending on the country, type of animal facilities (e.g., private, institutional, breeding, commercial) and institutional mandates, such contingency plans might not have been available at the start of the pandemic. Indeed, the current literature mainly describes risks such as power outage, flood, fire, severe storms or earthquakes, which are local and abrupt. For example, Charles River Japan overcame many such disaster situations in their production facility, but only the influenza outbreak of 2008 triggered them to develop a crisis management plan and a business continuity plan.⁷ Although rarely adapted to pandemics, basic preparedness concepts and terminology have been described and might be helpful to customize specific plans.^9,10 The challenge is to overcome a nation- or worldwide situation extending over a long period. In the first decade of the 21^st century, the multiple warnings of Influenza and SARS virus epidemics sensitized governmental agencies to the need of pandemic readiness planning and guidelines were published.¹¹ Here we describe the main objectives of such plans, adapted to a worldwide pandemic, from the viewpoint of an academic facility.The functions of animal facilities cannot easily be stopped due to emergencies such as the COVID-19 pandemic, even though the response may involve stopping all noncritical activities and quarantining workers. If these maintenance stop, the damage that occurs could be catastrophic in the short-, medium-, and long-term. Therefore, a good contingency plan for animal facilities is of utmost importance for maintaining what is required for a swift restart of activities when the situation returns to normal (or near-normal) conditions. Topics to be addressed range from experimental procedures that were ongoing when the quarantine began to conservation of all breeding and unique research models that are kept at the facility. In addition to these activities is the regular engineering maintenance of the facility, which vary depending on the facility''s age.The goal of plan is to prepare realistic and essential measures that can be implemented step-by-step, if and when the situation deteriorates, ensuring the required minimum of animal care and welfare while reducing non-essential activities usually performed at a facility (e.g., genotyping, experimental data collection, starting new experimental procedures, importing or exporting animals).     

Spatial cognition in Alzheimer's disease: subtypes of global-local impairment.

This study investigated whether subgroups of AD patients exhibit different patterns of impairment in analyzing global (configural) and local (detail) features of complex visual stimuli. A High Spatial AD subgroup (i.e., patients with better block constructions than naming) and a High Verbal AD subgroup (i.e., patients with better naming than block constructions) were impaired in analyzing both global and local forms. As predicted, however, the High Spatial AD patients exhibited greater impairment in analyzing the local forms than the High Verbal AD patients and normal controls. In contrast, the High Verbal AD patients exhibited greater impairment in analyzing the global forms than the High Spatial AD patients and normal controls. There was a striking separation of the subgroups: Using the local-global difference score, the hit rate for classifying these patients into the two subgroups was 91%. Robust correlations were found between the AD patients' ability to construct global and local forms and their scores on traditional visuospatial and verbal tests, respectively. The findings suggest that it may be misleading to subdivide AD patients using a verbal/spatial dichotomy, because even those AD patients who appear to have relative strengths on traditional visuospatial tests are likely to exhibit a primary impairment in analyzing local features of complex visual stimuli. The results underscore the importance of a process (qualitative) approach to neuropsychological assessment for a more valid understanding of the behavioral subtypes of Alzheimer's disease.     

Neuropsychological presentation of Ganser symptoms

We describe a patient with memory complaints whose history of head injury, polysubstance abuse and positive neurological findings suggested the presence of dementia. Neuropsychological testing revealed inconsistent performance plus multiple verbal and visuospatial approximate answers leading to the diagnosis of a Ganser episode. This case illustrates the importance of neuropsychological assessment in diagnosing Ganser symptoms and in differentiating this disorder from organic conditions and malingering.     

Adenovirus Infection in Pediatric Liver and Intestinal Transplant Recipients: Utility of DNA Detection by PCR

To evaluate the incidence of adenovirus (AdV) infection in pediatric liver and intestinal transplant recipients, the records of patients with possible AdV infection were reviewed for demographic data, symptomatology, methods of diagnosis, treatment and outcome. To evaluate the impact of polymerase chain reaction (PCR) amplification and identification of AdV DNA as a diagnostic test, the incidence and outcome of AdV before and after the introduction of PCR were compared. Adenovirus infection was identified in 4.1% of liver recipients and 20.8% of intestinal transplant recipients. The overall incidence of AdV did not increase over time, even following the introduction of PCR for virus detection. The higher incidence of AdV in the pediatric intestinal transplant recipients may be attributed to the frequent application of PCR methodology to intestinal biopsy material. Detection of AdV by PCR was associated with reduced mortality compared with detection by culture, either because of earlier detection of invasive disease or because PCR detects the presence of latent as well as active AdV.     

Air plethysmography: the answer in detecting past deep venous thrombosis

PURPOSE: In this study we assessed the accuracy of air plethysmography (APG) as a means of detecting earlier deep venous thrombosis (DVT), in comparison with venography, to develop a preoperative test for patients with varicose veins. METHODS: In this retrospective analysis of prospectively acquired data, 202 patients referred with the clinical suspicion of chronic venous obstruction (224 lower limbs) and 41 patients (41 lower limbs) who had symptoms and signs suggestive of DVT, but had deep veins that appeared normal on venography, were studied with both venography and APG. RESULTS: The results of venography were negative for past DVT in 169 legs and confirmed past DVT in 96 limbs. The DVTs were confined to the calf in 19 limbs and were found at popliteal level, more proximal, or both in 77 limbs. A total of 95% of the limbs that had earlier proximal DVT (73 of 77) were identified by means of an APG outflow fraction with occlusion of the superficial veins in the first second (OFs) of less than 28%. This is analogous to the Q wave of the electrocardiogram, which is a means of denoting the presence of myocardial infarction. The specificity rate of the method in the detection of past proximal DVT was 96%, the positive predictive value was 92%, and the negative predictive value was 98%. CONCLUSION: APG is a practical, inexpensive, easy-to-perform, accurate, noninvasive method for the diagnosis of hemodynamically significant (ie, proximal or extensive calf DVT) chronic venous obstruction that could replace venography.     

In situ hemodynamics of perforating veins in chronic venous insufficiency

PURPOSE: The prevalence of incompetent perforators increases linearly with the clinical severity of chronic venous insufficiency (CVI) and the presence of deep vein incompetence. Putative transmission of deep vein pressure to skin may cause dermal hypoxia and ulceration. Despite extensive prospective interest in the contribution of perforators toward CVI, their hemodynamic role remains controversial. The aim of this prospective study was to determine the in situ hemodynamic performance of incompetent perforating veins across the clinical spectrum of CVI, by means of duplex ultrasonography. METHODS: A total of 265 perforating veins of 90 legs that had clinical signs and symptoms consistent with CVI in 67 patients referred consecutively to the blood flow laboratory were studied. The clinical distribution of the examined limbs was CEAP(0), 10 limbs; CEAP(1-2), 39 limbs; CEAP(3-4), 21 limbs; and CEAP(5-6), 20 limbs. With the use of gated-Doppler ultrasonography on real-time B-mode imaging, the flow velocity waveforms were obtained from the lumen of perforators on release of manual distal leg compression in the sitting position and analyzed for peak and mean velocities, time to peak velocity, volume flow, venous volume displaced outward, and flow pulsatility. The diameter and duration of outward flow (abnormal reflux > 0.5 seconds) were also measured. RESULTS: Incompetent perforators had bigger diameters, higher peak and mean velocities and volume flow, longer time to peak velocity, and bigger venous volume displaced outward (VV(outward)) than competent perforators (all, P <.0001). The diameter of incompetent perforators did not change significantly with CEAP class (all, P >.1). Incompetent thigh and lower-third calf perforators had a significantly bigger diameter than perforators in the upper and middle calf combined (both, P <.05), in incompetent perforators: reflux duration was unaffected by CEAP class or site (P >.3); peak velocity was higher in those in CEAP(3-4) than those in CEAP(1-2) (P =.024); mean velocity in those in CEAP(3-6) during the first second of reflux was twice that of those in CEAP(1-2) (P <.0001); both higher volume flow and VV(outward) were found in the thigh perforators than those in the upper and middle calf thirds (P <.03); CEAP(3-6) volume flow and VV(outward), both in the first second, were twice that in those in CEAP(1-2) (P <.002); flow pulsatility in those in CEAP(5-6) was lower than in those in CEAP(1-2) (P =.014); in deep vein incompetence, higher peak velocity, volume flow, VV(outward), and diameter occurred than in its absence (P <.01). CEAP designation correlated significantly with mean velocity and flow pulsatility, both in the first second (r = 0.3, P <.01). The flow direction pattern in perforator incompetence was uniform across the CVI spectrum: inward on distal manual limb compression, and outward on its release; competent perforators had a smaller percentage of outward flow on limb compression (P <.01). CONCLUSION: In addition to an increase in diameter, perforator incompetence is characterized by significantly higher mean and peak flow velocities, volume flow, and venous volume displaced outward, and a lower flow pulsatility. Differences in early reflux enable a better hemodynamic stratification of incompetent perforators in CVI classes. In the presence of deep reflux, incompetent perforators sustain further hemodynamic impairment. In situ hemodynamics enable quantification of the function of perforators and can be used in the identification of the clinically relevant perforators and the impact of surgery.