Is muscle and protein loss relevant in long-term fasting in healthy men? A prospective trial on physiological adaptations.

BACKGROUND: Fasting is attracting an increasing interest as a potential strategy for managing diseases, including metabolic disorders and complementary cancer therapy. Despite concerns of clinicians regarding protein catabolism and muscle loss, evidence-based clinical data in response to long-term fasting in healthy humans are scarce. The objective of this study was to measure clinical constants, metabolic, and muscular response in healthy men during and after a 10 day fast combined with a physical activity programme. METHODS: Sixteen men (44 ± 14 years; 26.2 ± 0.9 kg/m2 ) fasted with a supplement of 200-250 kcal/day and up to 3 h daily low-intensity physical activity according to the peer-reviewed Buchinger Wilhelmi protocol. Changes in body weight (BW) and composition, basal metabolic rate (BMR), physical activity, muscle strength and function, protein utilization, inflammatory, and metabolic status were assessed during the 10 day fast, the 4 days of food reintroduction, and at 3 month follow-up. RESULTS: The 10 day fast decreased BW by 7% (-5.9 ± 0.2 kg, P < 0.001) and BMR by 12% (P < 0.01). Fat mass and lean soft tissues (LST) accounted for about 40% and 60% of weight loss, respectively, -2.3 ± 0.18 kg and -3.53 ± 0.13 kg, P < 0.001. LST loss was explained by the reduction in extracellular water (44%), muscle and liver glycogen and associated water (14%), and metabolic active lean tissue (42%). Plasma 3-methyl-histidine increased until Day 5 of fasting and then decreased, suggesting that protein sparing might follow early proteolysis. Daily steps count increased by 60% (P < 0.001) during the fasting period. Strength was maintained in non-weight-bearing muscles and increased in weight-bearing muscles (+33%, P < 0.001). Glycaemia, insulinemia, blood lipids, and blood pressure dropped during the fast (P < 0.05 for all), while non-esterified fatty acids and urinary beta-hydroxybutyrate increased (P < 0.01 for both). After a transient reduction, inflammatory cytokines returned to baseline at Day 10 of fasting, and LST were still lower than baseline values (-2.3% and -3.2%, respectively; P < 0.05 for both). CONCLUSIONS: A 10 day fast appears safe in healthy humans. Protein loss occurs in early fast but decreases as ketogenesis increases. Fasting combined with physical activity does not negatively impact muscle function. Future studies will need to confirm these first findings.

End-Expiratory Occlusion Test to Predict Fluid Responsiveness Is Not Suitable for Laparotomic Surgery.

BACKGROUND: The end-expiratory occlusion test predicts fluid responsiveness in ventilated intensive care patients; however, its utility in the operating room is questioned. We assessed end-expiratory occlusion test in laparotomic surgery for predicting volume expansion. METHODS: Forty-six patients were included in this study: stage 1 (n = 26) with an end-expiratory occlusion test of 15 seconds, followed by volume expansion, which consisted of 250 mL of colloid over 5 minutes and stage 2 (n = 20) with an end-expiratory occlusion test of 25 seconds followed by volume expansion. The last 10 patients had transdiaphragmatic pressures probed. Patients with an increase in cardiac index >15% after volume expansion were responders. Pulse pressure variation, stroke volume (SV) index, and cardiac index were analyzed. Receiver operating characteristic curves were established for changes in SV and pulse pressure induced by end-expiratory occlusion test and pulse pressure variation using the responders status for volume expansion as outcome. RESULTS: A total of 44 (38%) volume expansions were deemed responders. After end-expiratory occlusion test of 15 seconds, no hemodynamic variables were significantly increased. After end-expiratory occlusion test of 25 seconds, SV index increased in responders (37.1 ± 8.8 mL/m after end-expiratory occlusion test of 25 seconds versus 35.7 ± 8.6 before; P < .0001). End-expiratory occlusion test could not discriminate responders from nonresponders. Only pulse pressure variation had significantly different area under the curve from that expected by chance (0.7 [0.57-0.81]; P = .002 for end-expiratory occlusion test of 15 seconds; and 0.78 [0.64-0.89]; P = .0001 for end-expiratory occlusion test of 25 seconds). After laparotomy, gastric pressure decreased significantly (4 [2.75-5] vs 2 [2-4] cm H2O; P = .0417); no difference was noticed in the transdiaphragmatic gradient. CONCLUSIONS: End-expiratory occlusion test was not reliable to discriminate responders from nonresponders after volume expansion during laparotomic surgery.

A Hemodynamic Monitor as a Simulation Tool, a Novel Use of the PiCCO2: Technical Description of the Method and Its Application.

INTRODUCTION: The PiCCO2 is a commonly used monitor, which education remains theoretical and demonstration based. Simulation allows active learning, which may help achieve a better understanding and handling of this device, hence a safer and more effective use. Because of the lack of availability of dedicated simulators and the uselessness of the demonstration mode of monitors for simulation purpose, simulation remains seldom used. We will describe a novel use of the PiCCO2 for simulation training and its experiment in high-fidelity simulation (HFS). METHODS: A standard PiCCO2 was modified with software allowing its transformation into a simulator. The values displayed on the screen were managed in real time by an operator using a standard laptop linked to the monitor and using a standard disposable catheter set to execute simulated transpulmonary thermodilution. Nineteen volunteers were requested to assess the realism of the device during scenarios in which the PiCCO2S (simulator) was used in an HFS environment, with a mannequin reproducing a septic shock condition. RESULTS: Two experimental sessions were made. PiCCO2S was used in the contextualized setting of HFS, which allowed a good interactivity between the device and its users. Participants had a positive perception of the realism as well as the method's adequacy to achieve a better understanding of the PiCCO2. CONCLUSIONS: The PiCCO2S could be obtained from a serial device. Its integration in HFS provided a realistic handling of the device. A built-in simulation mode into serial medical devices may give users an easy access to training.

Clinical and imaging factors associated with severe complications of cervical necrotizing fasciitis.

PURPOSE: Cervical necrotizing fasciitis (CNF) is a severe and debilitating disease that requires intensive care unit (ICU) management and prompt surgical treatment to reduce morbidity and mortality. The aim of this study was to estimate the incidence and factors associated with severe complications of CNF. METHODS: We reviewed the medical records of consecutive patients hospitalized in an ICU from 2007 to 2012. The data were collected retrospectively; initial cervical and thoracic computed tomography (CT) scans, performed on admission, were reviewed by an experienced and blinded radiologist to determine CNF complications. RESULTS: A cohort of 160 patients admitted for CNF was included. The following complications of CNF were found: bilateral extension of CNF (28%), internal jugular vein thrombosis (21%), descending necrotic effusion (14%), mediastinitis (24%), and mortality (4%); 53% had at least one complication, and 48% had at least one cervical complication. On the basis of a univariate analysis, the significant independent factors are odynophagia, dyspnea, oral glucocorticoids intake before admission, and pharyngeal source. Oral nonsteroidal anti-inflammatory drug intake before admission does not have any impact. The initial CNF complications increased both the duration of mechanical ventilation and the length of stay in the ICU. On the basis of a multivariate analysis, the independent factors for severe complications are pharyngeal CNF and oral glucocorticoid intake before admission. CONCLUSIONS: Our study demonstrated that an initial cervico-thoracic CT scan revealed a high incidence of cervical and mediastinal CNF complications that all needed immediate management. Those severe complications might be avoidable as they were associated, at least partially, with prehospital oral glucocorticoid intake.