A Modified Approach to Induce Predictable Congestive Heart Failure by Volume Overload in Rats

The model of infrarenal aortocaval fistula (ACF) has recently gained new interest in its use to investigate cardiac pathophysiology. Since in previous investigations the development of congestive heart failure (CHF) was inconsistent and started to develop earliest 8-10 weeks after fistula induction using a 18G needle, this project aimed to induce a predictable degree of CHF within a definite time period using a modified approach. An aortocaval fistula was induced in male Wistar rats using a 16G needle as a modification of the former 18G needle-technique described by Garcia and Diebold. Results revealed within 28 +/- 2 days of ACF significantly increased heart and lung weight indices in the ACF group accompanied by elevated filling pressure. All hemodynamic parameters derived from a pressure-volume conductance-catheter in vivo were significantly altered in the ACF consistent with severe systolic and diastolic left ventricular dysfunction. This was accompanied by systemic neurohumoral activation as demonstrated by elevated rBNP-45 plasma concentrations in every rat of the ACF group. Furthermore, the restriction in overall cardiac function was associated with a beta 1- and beta 2-adrenoreceptor mRNA downregulation in the left ventricle. In contrast, beta 3-adrenoreceptor mRNA was upregulated. Finally, electron microscopy of the left ventricle of rats in the ACF group showed signs of progressive subcellular myocardial fragmentation. In conclusion, the morphometric, hemodynamic and neurohumoral characterization of the modified approach revealed predictable and consistent signs of congestive heart failure within 28 +/- 2 days. Therefore, this modified approach might facilitate the examination of various questions specific to CHF and allow for pharmacological interventions to determine pathophysiological pathways

Enhanced Recovery After Surgery (ERAS) for gastrointestinal surgery, part 1:pathophysiological considerations

BACKGROUND: The present article has been written to convey concepts of anaesthetic care within the context of an Enhanced Recovery After Surgery (ERAS) programme, thus aligning the practice of anaesthesia with the care delivered by the surgical team before, during and after surgery. METHODS: The physiological principles supporting the implementation of the ERAS programmes in patients undergoing major abdominal procedures are reviewed using an updated literature search and discussed by a multidisciplinary group composed of anaesthesiologists and surgeons with the aim to improve perioperative care. RESULTS: The pathophysiology of some key perioperative elements disturbing the homoeostatic mechanisms such as insulin resistance, ileus and pain is here discussed. CONCLUSIONS: Evidence‐based strategies aimed at controlling the disruption of homoeostasis need to be evaluated in the context of ERAS programmes. Anaesthesiologists could, therefore, play a crucial role in facilitating the recovery process

Enhanced Recovery After Surgery (ERAS) for gastrointestinal surgery, part 2:consensus statement for anaesthesia practice

Background The present interdisciplinary consensus review proposes clinical considerations and recommendations for anaesthetic practice in patients undergoing gastrointestinal surgery with an Enhanced Recovery after Surgery (ERAS) programme. Methods Studies were selected with particular attention being paid to meta-analyses, randomized controlled trials and large prospective cohort studies. For each item of the perioperative treatment pathway, available English-language literature was examined and reviewed. The group reached a consensus recommendation after critical appraisal of the literature. Results This consensus statement demonstrates that anaesthesiologists control several preoperative, intraoperative and postoperative ERAS elements. Further research is needed to verify the strength of these recommendations. Conclusions Based on the evidence available for each element of perioperative care pathways, the Enhanced Recovery After Surgery (ERAS ®) Society presents a comprehensive consensus review, clinical considerations and recommendations for anaesthesia care in patients undergoing gastrointestinal surgery within an ERAS programme. This unified protocol facilitates involvement of anaesthesiologists in the implementation of the ERAS programmes and allows for comparison between centres and it eventually might facilitate the design of multi-institutional prospective and adequately powered randomized trials

Development and Feasibility Study of an Algorithm for Intraoperative Goal-directed Haemodynamic Management in Noncardiac Surgery

This study developed an evidence-based, goal-directed haemodynamic management algorithm to standardize intraoperative haemodynamic therapy. A systematic literature search identified three haemodynamic management goals: stroke volume optimization by fluid therapy; maintenance of a target mean arterial pressure by vasopressor therapy; maintenance of a target cardiac index >= 2.5 l/min per m(2) by inotropic therapy. The algorithm was adapted to international standards and consensus was reached through a modified Delphi method at international meetings. Implementation of the algorithm into routine intraoperative management in noncardiac surgery was shown to be feasible. Compared with conventional haemodynamic management, use of the algorithm significantly reduced length of hospital stay, requirement for ventilation and incidence of prolonged hospital stay, thereby resulting in reduced hospital costs