The impact of haemodilution and bypass pump flow on cerebral oxygen desaturation during cardiopulmonary bypass--A comparison of two systems of cardiopulmonary bypass.

OBJECTIVE: To determine the influence of haemodilution, bypass flow rates and calculated oxygen delivery during cardiopulmonary bypass (CPB) with either a conventional CPB (C-CPB) circuit or a miniaturised (Mini-CPB) circuit on cerebral oxygen desaturation. The effect of minimal haemodilution with a Mini-CPB was investigated. PARTICIPANTS: Eighty patients scheduled for elective cardiac surgery. INTERVENTION: Oxygenated haemoglobin (O2Hb) and tissue oxygenation index (TOI) were measured with near-infrared spectroscopy (NIRS). RESULTS: The average indexed bypass pump flow was significantly lower with Mini-CPB. When combined with haemoglobin concentration, the average oxygen delivery was the same between groups. Patients in the C-CPB group had a greater duration and severity of cerebral desaturation to a level <20% below baseline values, but none reached the depth and duration of the cerebral desaturation associated with poor outcome. Cerebral oxygen desaturation with C-CPB was significantly associated with low flows during bypass, whereas desaturation with Mini-CPB was associated with low perioperative haemoglobin concentration.

Spatio-temporal modeling of the African swine fever epidemic in the Russian Federation, 2007-2012.

In 2007 African swine fever (ASF) entered Georgia and in the same year the disease entered the Russian Federation. From 2007 to 2012 ASF spread throughout the southern region of the Russian Federation. At the same time several cases of ASF were detected in the central and northern regions of the Russian Federation, forming a northern cluster of outbreaks in 2011. This northern cluster is of concern because of its proximity to mainland Europe. The aim of this study was to use details of recorded ASF outbreaks and human and swine population details to estimate the spatial distribution of ASF risk in the southern region of the European part of the Russian Federation. Our model of ASF risk was comprised of two components. The first was an estimate of ASF suitability scores calculated using maximum entropy methods. The second was an estimate of ASF risk as a function of Euclidean distance from index cases. An exponential distribution fitted to a frequency histogram of the Euclidean distance between consecutive ASF cases had a mean value of 156 km, a distance greater than the surveillance zone radius of 100-150 km stated in the ASF control regulations for the Russian Federation. We show that the spatial and temporal risk of ASF expansion is related to the suitability of the area of potential expansion, which is in turn a function of socio-economic and geographic variables. We propose that the methodology presented in this paper provides a useful tool to optimize surveillance for ASF in affected areas.

The implementation and effectiveness of an enhanced recovery programme after oesophago-gastrectomy: a prospective cohort study.

BACKGROUND: Oesophageal resection is notoriously complicated and produces a cohort of patients prone to postoperative complications. Maintaining quality care demands a systematic approach to patient management yet postoperative recovery after oesophagectomy is often needlessly inefficient, heterogeneous and governed by the idiosyncrasies of the operating surgeon. Enhanced recovery after surgery (ERAS) programmes are now well established in colorectal surgery and here we describe the implementation and effectiveness of an ERAS programme for the postoperative management of Ivor Lewis oesophago-gastrectomy (ILOG). METHODS: An ERAS programme was devised and implemented with the support of a dedicated in-hospital task-force. Three consultant surgeons allocated consecutive patients to the programme (ERAS) and outcomes were compared to consecutive patients not on the ERAS programme (non-ERAS) and a pre-ERAS cohort (pre-ERAS). Principal outcome measures were total length of stay (TLOS), Accordion postoperative complication grade and 30-day readmission rate. RESULTS: 75 patients were enrolled on the ERAS programme, 41 continued as a non-ERAS cohort and 80 consecutive pre-ERAS patients were identified. A significant improvement in median TLOS was observed in the ERAS group (10 days r.7-58) compared to pre-ERAS (13 days r. 8-57) (p = <0.001) and non-ERAS patients (13 days r.8-42) (p = <0.001). No significant difference in Accordion scores for postoperative complications or 30-day readmission rates were observed. DISCUSSION: The introduction of an ERAS programme after ILOG can significantly reduce TLOS without jeopardising patient safety or clinical outcomes. The successful introduction of an ERAS programme requires full motivation and support from all team members including the patient.

African swine fever in the Russian Federation: spatio-temporal analysis and epidemiological overview.

African swine fever is viral disease of domestic and wild pigs which leads to almost total mortality and causes great economic losses due to absence of vaccine. Having been introduced into the Russian Federation in 2007 the disease has spread widely in the southern region of the country and since 2011 has demonstrated a tendency to form a secondary endemic zone in the central part of the country. In the present study spatio-temporal patterns of ASF diffusion in the populations of wild and domestic pigs are analyzed. The structure of the domestic swine population is conventionally divided into a sub-population at low biosecurity (77% of the total number of outbreaks in domestic pigs) and a population at high biosecurity (23%). The statistics of ASF cases registered in each of these sub-populations is presented. The possible causes of ASF diffusion across the country are discussed. The use of geo-information technologies (GIS) enabled confirmation of the conclusion that an epidemic center has shifted into the central part of Russia. The main conclusions of this study are that: (1) anthropogenic factors play the leading role in the spread of ASF across the territory of the RF; (2) small-scale private holdings (low biosecurity population) are more exposed to ASF virus introduction; (3) there is a high risk of diffusion of ASFV from the secondary endemic zone in the central part of the RF to neighboring regions.

Cartographical analysis of African swine fever outbreaks in the territory of the Russian Federation and computer modeling of the basic reproduction ratio.

African swine fever (ASF), have been introduced into the Russian Federation from Transcaucasia countries, has spread widely across the territory of the southern region of Russia since 2008. In this work we present an analysis of the spatial and temporal spread of the disease, determine risk factors by means of GIS tools and model the dynamics of the epidemic process both within infected premises (farms) and at the between-farm level to estimate the basic reproduction ratio R(0). The analysis allowed us to make a conclusion about the anthropogenic nature of the risk factors for disease spread. The major significant risk factors identified were: density of the road network, density of domestic swine population and density of water bodies in the study area. The basic reproduction ratio was estimated to range from 2 to 3 at the between-farm level and from 8 to 11 within the infected farms. These initial studies of the ASF epidemic provide information on which to based control and prevention programs.

Reliable long-term non-pulsatile circulatory support without anticoagulation.

OBJECTIVE: The Terumo implantable left ventricular assist system (T-ILVAS) consists of a titanium centrifugal pump with a unique magnetically suspended impeller producing continuous (non-pulsatile) flow up to 10 l/min. The interior surface is heparin-coated and there is no purge system. We implanted the device into six sheep to ascertain in-vivo haemodynamic function, mechanical reliability and biocompatibility. METHODS: The T-ILVAS was implanted via left thoracotomy without cardiopulmonary bypass. The inflow cannula was placed in the left ventricular apex and a Dacron outflow graft anastomosed to the descending aorta. All animals recovered well. No anticoagulation (heparin or warfarin) was given after the surgery. Suspension position, motor current, impeller speed and pump flow were continuously monitored and stored by on-line computer. Serial blood samples were collected to determine haematological and biochemical indices of renal function, liver function and haemolysis. All animals were electively euthanized between 3 and 7 months postoperatively. The explanted pumps were examined for mechanical reliability and thrombus formation. Major organs were examined macroscopically and histologically for thromboembolism. RESULTS: All animals appeared completely normal for up to 210 days. At speeds between 1500 and 2000 rev./min the device pumped up to 8 l/min capturing all mitral flow. There were no major complications (pump failure, thromboembolism, haemorrhage, or driveline infection). Indices of haemolysis, liver and renal function remained within normal limits. All pumps were mechanically sound and free from thrombus. One embolus was found in a sectioned kidney. CONCLUSION: The T-ILVAS successfully supported the systemic circulation without anticoagulation for up to 210 days. Mechanical reliability and biocompatibility were demonstrated. Organ function remained within normal limits during continuous non-pulsatile flow.