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

Early improvement of respiratory function after surgical plication for unilateral diaphragmatic paralysis

We reported an unusual case of symptomatic diaphragmatic paralysis in an elderly patient with progressive respiratory-dependent limitation of her daily activities. Surgical plication of the affected hemidiaphragm resulted in early clinical and physiological improvement

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

The European Respiratory Society and European Society of Thoracic Surgeons clinical guidelines for evaluating fitness for radical treatment (surgery and chemoradiotherapy) in patients with lung cancer

The European Respiratory Society (ERS) and the European Society of Thoracic Surgeons (ESTS) established a joint task force with the purpose to develop clinical evidence-based guidelines on evaluation of fitness for radical therapy in patients with lung cancer. The following topics were discussed, and are summarized in the final report along with graded recommendations: Cardiologic evaluation before lung resection; lung function tests and exercise tests (limitations of ppoFEV1; DLCO: systematic or selective?; split function studies; exercise tests: systematic; low-tech exercise tests; cardiopulmonary (high tech) exercise tests); future trends in preoperative work-up; physiotherapy/rehabilitation and smoking cessation; scoring systems; advanced care management (ICU/HDU); quality of life in patients submitted to radical treatment; combined cancer surgery and lung volume reduction surgery; compromised parenchymal sparing resections and minimally invasive techniques: the balance between oncological radicality and functional reserve; neoadjuvant chemotherapy and complications; definitive chemo and radiotherapy: functional selection criteria and definition of risk; should surgical criteria be re-calibrated for radiotherapy?; the patient at prohibitive surgical risk: alternatives to surgery; who should treat thoracic patients and where these patients should be treated

Detection of extended-spectrum β-lactamase and carbapenemase activity in Gram-negative bacilli using liquid chromatography - tandem mass spectrometry

PURPOSE: Several mass spectrometry-based methods for antimicrobial sensitivity testing have been described in recent years. They offer an alternative to commercially available testing systems which were considered to have disadvantages in terms of cost- and time-efficiency. The aim of this study was to develop a LC-MS/MS-based antibiotic hydrolysis assay for evaluating antimicrobial resistance of Gram-negative bacteria. METHODS: Four species of Gram-negative bacilli (Klebsiella pneumoniae, Escherichia coli, Providencia stuartii and Acinetobacter baumannii) were tested against six antibiotics from three different classes: ampicillin, meropenem, imipenem, ceftazidime, ceftriaxone and cefepime. Bacterial suspensions from each species were incubated with a mixture of the six antibiotics. Any remaining antibiotic following incubation were measured using LC-MS/MS. The results were interpreted using measurements obtained for an E. coli strain sensitive to all antibiotics and expressed as percentage of hydrolyzed antibiotic. These were subsequently compared to commercially-available system for the bacteria identification and susceptibility testing. RESULTS: Overall, LC-MS/MS assay and commercial antimicrobial susceptibility platform results showed good agreement in terms of an organism being resistant/sensitive to an antibiotic. The time required to complete the LC-MS/MS-based hydrolysis test was under 5 h, significantly shorter that commercially available susceptibility testing platforms. CONCLUSION: By using a sensitive strain for results interpretation and simultaneous use of multiple antibiotics, the proposed protocol offers improved robustness and multiplexing over previously described methods for antibiotic sensitivity testing. Nevertheless, further research is needed before routine assimilation of the method, especially for strains with intermediate resistance

Preoperative Exercise Training to Prevent Postoperative Pulmonary Complications in Adults Undergoing Major Surgery. A Systematic Review and Meta-analysis with Trial Sequential Analysis.

Rationale: Poor preoperative physical fitness and respiratory muscle weakness are associated with postoperative pulmonary complications (PPCs) that result in prolonged hospital length of stay and increased mortality.Objectives: To examine the effect of preoperative exercise training on the risk of PPCs across different surgical settings.Methods: We searched MEDLINE, Web of Science, Embase, the Physiotherapy Evidence Database, and the Cochrane Central Register, without language restrictions, for studies from inception to July 2020. We included randomized controlled trials that compared patients receiving exercise training with those receiving usual care or sham training before cardiac, lung, esophageal, or abdominal surgery. PPCs were the main outcome; secondary outcomes were preoperative functional changes and postoperative mortality, cardiovascular complications, and hospital length of stay. The study was registered with PROSPERO (International Prospective Register of Systematic Reviews).Results: From 29 studies, 2,070 patients were pooled for meta-analysis. Compared with the control condition, preoperative exercise training was associated with a lower incidence of PPCs (23 studies, 1,864 patients; relative risk, 0.52; 95% confidence interval [CI], 0.41 to 0.66; grading of evidence, moderate); Trial Sequential Analysis confirmed effectiveness, and there was no evidence of difference of effect across surgeries, type of training (respiratory muscles, endurance or combined), or preoperative duration of training. At the end of the preoperative period, exercise training resulted in increased peak oxygen uptake (weighted mean difference [WMD], +2 ml/kg/min; 99% CI, 0.3 to 3.7) and higher maximal inspiratory pressure (WMD, +12.2 cm H <sub>2</sub> O; 99% CI, 6.3 to 18.2). Hospital length of stay was shortened (WMD, -2.3 d; 99% CI, -3.82 to -0.75) in the intervention group, whereas no difference was found in postoperative mortality.Conclusions: Preoperative exercise training improves physical fitness and reduces the risk of developing PPCs while minimizing hospital resources use, regardless of the type of intervention and surgery performed.Systematic review registered with https://www.crd.york.ac.uk/prospero/ (CRD 42018096956)

Cardiac output by model flow method from intra-arterial and finger tip pulse pressure profiles

Modelflow®, when applied to non-invasive fingertip pulse pressure recordings, is a poor predictor of cardiac output (Q’ litre· min-1). The use of constants established from the aortic elastic characteristics, which differ from those of finger arteries, may introduce signal distortions, leading to errors in computing Q’. We therefore hypothesized that peripheral recording of pulse pressure profiles undermines the measurement of Q’ withModelflow®, so we compared Modelflow® beat-by-beat Q’ values obtained simultaneously non-invasively from the finger and invasively from the radial artery at rest and during exercise. Seven subjects (age, 24.0 + - 2.9 years; weight, 81.2 + - 12.6 kg) rested, then exercised at 50 and 100 W, carrying a catheter with a pressure head in the left radial artery and the photoplethysmographic cuff of a finger pressure device on the third and fourth fingers of the contralateral hand. Pulse pressure from both devices was recorded simultaneously and stored on a PC for subsequent Q’ computation. The mean values of systolic, diastolic and mean arterial pressure at rest and exercise steady state were significantly (P < 0.05) lower from the finger than the intra-arterial catheter. The corresponding mean steady-state Q’ obtained from the finger (Q’porta) was significantly (P < 0.05) higher than that computed from the intra-arterial recordings (Q’pia). The line relating beat-by-beat Q’porta and Q’pia was y = 1.55x - 3.02 (r2 = 0.640). The bias was 1.44 litre · min-1 and the precision was 2.84 litre · min-1.The slope of this line was significantly higher than 1, implying a systematic overestimate of Q’ by Q’porta with respect to Q’pia. Consistent with the tested hypothesis, these results demonstrate that pulse pressure profiles from the finger provide inaccurate absolute Q’ values with respect to the radial artery, and therefore cannot be used without correction with a calibration factor calculated previously by measuring Q’ with an independent method

Yield gap analyses to estimate attainable bovine milk yields and evaluate options to increase production in Ethiopia and India

Livestock provides an important source of income and nourishment for around one billion rural households worldwide. Demand for livestock food products is increasing, especially in developing countries, and there are opportunities to increase production to meet local demand and increase farm incomes. Estimating the scale of livestock yield gaps and better understanding factors limiting current production will help to define the technological and investment needs in each livestock sector. The aim of this paper is to quantify livestock yield gaps and evaluate opportunities to increase dairy production in Sub-Saharan Africa and South Asia, using case studies from Ethiopia and India. We combined three different methods in our approach. Benchmarking and a frontier analysis were used to estimate attainable milk yields based on survey data. Household modelling was then used to simulate the effects of various interventions on dairy production and income. We tested interventions based on improved livestock nutrition and genetics in the extensive lowland grazing zone and highland mixed crop-livestock zones of Ethiopia, and the intensive irrigated and rainfed zones of India. Our analyses indicate that there are considerable yield gaps for dairy production in both countries, and opportunities to increase production using the interventions tested. In some cases, combined interventions could increase production past currently attainable livestock yields