Influence of thoracic epidural analgesia on cardiovascular autonomic control after thoracic surgery

Background. Thoracic epidural analgesia (TEA) is effective in alleviating pain after major thoracoabdominal surgery and may also reduce postoperative mortality and morbidity. This study investigated cardiovascular autonomic control in patients undergoing elective thoracic surgery and its modulation by continuous TEA. Methods. Thirty‐eight patients were randomly assigned to receive patient‐controlled analgesia (PCA group) or thoracic epidural analgesia (TEA group) with doses of bupivacaine (0.25% during operation, 0.125% after operation) and fentanyl (2 µgml-1). Heart rate variability (HRV), baroreflex function and pressure response to nitroglycerine and phenylephrine were assessed before operation, 4 h after the end of surgery (POD 0) and on the first and second postoperative days (POD1 and POD2). Results. Early after surgery, all HRV variables and baroreflex sensitivities were markedly decreased in both groups. In the TEA group, total HRV and its high‐frequency components (HF) increased towards preoperative values at POD1 and POD2, whereas the ratio of low to high frequencies (LF/HF) was significantly reduced (mean (sd), -44 (15)% at POD 0, -38 (17)% at POD1, -37 (18%) at POD2) and associated with blunting of the postoperative increase in heart rate and blood pressure. In the PCA group, the ratio of LF/HF remained unchanged and the decrements in HRV variables persisted until POD2. In the two groups, baroreflex sensitivities and pressure responses recovered preoperative values at POD2. Conclusions. In contrast with PCA management, TEA using low concentrations of bupivacaine and fentanyl blunted cardiac sympathetic neural drive, resulting in vagal predominance, while HRV variables were better restored after surgery. Br J Anaesth 2003; 91: 525-3

Superadiabatic dynamical density functional study of Brownian hard-spheres in time-dependent external potentials

Superadiabatic dynamical density functional theory (superadiabatic-DDFT), a first-principles approach based on the inhomogeneous two-body correlation functions, is employed to investigate the response of interacting Brownian particles to time-dependent external driving. Predictions for the superadiabatic dynamics of the one-body density are made directly from the underlying interparticle interactions, without need for either adjustable fit parameters or simulation input. The external potentials we investigate have been chosen to probe distinct aspects of structural relaxation in dense, strongly interacting liquid states. Nonequilibrium density profiles predicted by the superadiabatic theory are compared with those obtained from both adiabatic DDFT and event-driven Brownian dynamics simulation. Our findings show that superadiabatic-DDFT accurately predicts the time-evolution of the one-body density

Mean-Field Theory of Inhomogeneous Fluids

The Barker-Henderson perturbation theory is a bedrock of liquid-state physics, providing quantitative predictions for the bulk thermodynamic properties of realistic model systems. However, this successful method has not been exploited for the study of inhomogeneous systems. We develop and implement a first-principles 'Barker-Henderson density functional', thus providing a robust and quantitatively accurate theory for classical fluids in external fields. Numerical results are presented for the hard-core Yukawa model in three dimensions. Our predictions for the density around a fixed test particle and between planar walls are in very good agreement with simulation data. The density profiles for the free liquid vapour interface show the expected oscillatory decay into the bulk liquid as the temperature is reduced towards the triple point, but with an amplitude much smaller than that predicted by the standard mean-field density functional

Perioperative mortality and major cardio-pulmonary complications after lung surgery for non-small cell carcinoma

Objectives: A database of patients operated of lung cancer was analyzed to evaluate the predictive risk factors of operative deaths and life-threatening cardiopulmonary complications. Methods: From 1990 to 1997, data were collected concerning 634 consecutive patients undergoing lung resection for non-small cell carcinoma in an academic medical centre and a regional hospital. Operations were managed by a team of experienced surgeons, anaesthesiologists and chest physicians. Operative mortality was defined as death within 30 days of operation and/or intra-hospital death. Respiratory failure, myocardial infarct, heart failure, pulmonary embolism and stroke were considered as major non-fatal complications. Preoperative risk factors, extent of surgery, pTNM staging, perioperative mortality and major cardiopulmonary complications were recorded and evaluated using chi-square statistics and multivariate logistic regression. Results: Complete data were obtained in 621 cases. The overall operative mortality was 3.2% (n=19). Cardiovascular complications (n=10), haemorrhage (n=4) and sepsis or acute lung injury (n=5) were incriminated as the main causative factors. In addition, there were 13 life-threatening complications (2.1%) consisting in strokes (n=4), myocardial infarcts (n=5), pulmonary embolisms (n=1), acute lung injury (n=1) and respiratory failure (n=2). Four independent predictors of operative death were identified: pneumonectomy, evidence of coronary artery disease (CAD), ASA class 3 or 4 and period 1990-93. In addition, the risk of major complications was increased in hypertensive patients and in those belonging to ASA class 3 or 4. A trend towards improved outcome was observed during the second period, from 1994 to 97. Conclusion: Our data demonstrate that perioperative mortality is mainly dependent on the extent of surgery, the presence of CAD and provision of adequate medical and nursing care. Preoperative testing and interventions to reduce the cardiovascular risk factors may help to further improve perioperative outcom

Integrated community based human and animal syndromic surveillance in Adadle district of the Somali region of Ethiopia

The economy of Ethiopia largely depends on agriculture and roughly 80% of the households have direct contact with domestic animals which make the community vulnerable to zoonotic diseases, especially in pastoral areas like the Somali Regional State (SRS) of Ethiopia. However, in addition to low reporting rates, especially in livestock, there is also lack of coordination between public health and animal health surveillance and there is no linkage between public health system and animal health system and mechanism or structure for sharing information on zoonotic diseases in SRS. In view of these challenges, a small scale study was conducted to evaluate the feasibility of mobile communication in the early detection of human and animal syndromes in remote pastoral areas including where there are no human and animal health facilities by engaging local communities in the diseases surveillance. Method: A small scale study, testing a community based human and animal syndromic surveillance was conducted from August 2017 to February 2018 in 20 villages in four Kebeles of Adadle district in the SRS with an estimated 1390 households and 112,850 livestock. The selected community leaders were trained on disease surveillance and detection. The communication was done by direct calls. Two dollars per month were provided to the village leaders recruited for the surveillance. Results: A total of 904 and 671 human and animal syndrome cases were reported in seven months of the study period. In addition to syndromes, suspected anthrax, sheep and goat pox (SGP), rabies, salmonellosis and mass abortion outbreaks were reported in animals. In humans, suspected cholera and chicken pox outbreaks were reported. Furthermore, tuberculosis and malaria cases were also confirmed in the study villages. In humans, gastrointestinal tract (GIT) disorder was the most common syndrome observed, which constituted (42.8%) of all syndromes, followed by respiratory disorder (37.8%) and febrile illness (15.5%). In livestock, cattle contributed (40.8%) of all cases of illness, while sheep, goats and camels contributed 24.1%, 18% and 17% of the cases respectively. Responses were organized for emergency treatment and vaccination campaigns against certain suspected disease outbreaks and emergencies such as SGP and cholera. Conclusion: This study suggests that engaging and empowering the village local leaders in disease surveillance in pastoral setting areas, including where there are no human and animal health facilities, coupled with mobile technologies (non-smart phone), would improve early detection and response to human and animal health events including zoonotic emergencies, and consequently improve the reporting rate at district, regional and national level. However, the collaboration between sectors (human health and animals health) and the capacity to respond to zoonotic diseases and etiological identification are crucial elements for effective integrated human and animals disease surveillance and response