Effect of intra-operative intravenous lidocaine on opioid consumption after bariatric surgery: a prospective, randomised, blinded, placebo-controlled study.

Peri-operative lidocaine infusion warrants investigation in bariatric surgery because obese patients present different physiological and pharmacological risks. This single-centre, prospective, randomised double-blind placebo-controlled study enrolled obese patients scheduled for laparoscopic bariatric surgery using an enhanced recovery protocol. Patients received either lidocaine (bolus of 1.5 mg.kg-1 , then a continuous infusion of 2 mg.kg-1 .h-1 until the end of the surgery, then 1 mg.kg-1 .h-1 for 1 h in the recovery area) or identical volumes and rates of 0.9% saline. The primary outcome was the consumption of the equivalent of oxycodone consumption over the first 3 postoperative days. Secondary outcomes were: postoperative pain; incidence of nausea and vomiting; bowel function recovery; and lengths of stay in the recovery area and in hospital. Plasma concentrations of lidocaine were measured. On the 178 patients recruited, data were analysed from 176. The median (IQR [range]) equivalent intravenous oxycodone consumption was 3.3 mg (0.0-6.0 [0.0-14.5]) and 5.0 mg (3.3-7.0 [3.3-20.0]) in the lidocaine and saline groups, respectively (difference between medians (95%CI): 1.7 (0.6-3.4) mg; p = 0.004). Length of stay in the recovery area, postoperative pain, nausea and vomiting, day of recovery of bowel function, and length of stay in hospital were not different between groups. Mean (SD) lidocaine plasma concentrations were 2.44 (0.70) µg.ml-1 and 1.77 (0.51) µg.ml-1 at the end of surgery and 1 hour after the end of infusion, respectively. Lidocaine infusion during bariatric surgery resulted in a clinically non-relevant difference in postoperative oxycodone consumption.

Accuracy and precision of non-invasive cardiac output monitoring devices in perioperative medicine: a systematic review and meta-analysis†.

Cardiac output (CO) measurement is crucial for the guidance of therapeutic decisions in critically ill and high-risk surgical patients. Newly developed completely non-invasive CO technologies are commercially available; however, their accuracy and precision have not recently been evaluated in a meta-analysis. We conducted a systematic search using PubMed, Cochrane Library of Clinical Trials, Scopus, and Web of Science to review published data comparing CO measured by bolus thermodilution with commercially available non-invasive technologies including pulse wave transit time, non-invasive pulse contour analysis, thoracic electrical bioimpedance/bioreactance, and CO2 rebreathing. The non-invasive CO technology was considered acceptable if the pooled estimate of percentage error was <30%, as previously recommended. Using a random-effects model, sd, pooled mean bias, and mean percentage error were calculated. An I2 statistic was also used to evaluate the inter-study heterogeneity. A total of 37 studies (1543 patients) were included. Mean CO of both methods was 4.78 litres min−1. Bias was presented as the reference method minus the tested methods in 15 studies. Only six studies assessed the random error (repeatability) of the tested device. The overall random-effects pooled bias (limits of agreement) and the percentage error were −0,13 [−2.38 , 2.12] litres min−1 and 47%, respectively. Inter-study sensitivity heterogeneity was high (I2=83%, P<0.001). With a wide percentage error, completely non-invasive CO devices are not interchangeable with bolus thermodilution. Additional studies are warranted to demonstrate their role in improving the quality of care.

Assessment of changes in lactate concentration with intravascular microdialysis during high-risk cardiac surgery using the trend interchangeability method.

Background: Blood lactate is a strong predictor of mortality, and repeated blood lactate assays are recommended during surgery in high-risk patients. We hypothesized that the use of intravascular microdialysis incorporated in a central venous catheter would be interchangeable with the reference blood gas technique to monitor changes in blood lactate. Methods: Microdialysis and central venous blood lactate measurements were recorded simultaneously in high-risk cardiac surgical patients. The correlation between absolute values was determined by linear regression, and the Bland-Altman test for repeated measurements was used to compare bias, precision, and limits of agreement. Changes in lactate measurements were evaluated with a four-quadrant plot and trend interchangeability method (TIM). Results: In the 23 patients analysed, the central venous catheter was used as part of standard care, with no complications. The correlation coefficient for absolute values ( n =104) was 0.96 ( P <0.0001). The bias, precision, and limits of agreement were -0.19, 0.51, and -1.20 to 0.82 mmol litre -1 , respectively. The concordance rate for changes in blood lactate measurements ( n =80) was 94% with the four-quadrant plot. In contrast, the TIM showed that 23 (29) changes in lactate measurements were not interpretable, and among the remaining 57 (71) interpretable changes, 18 (32) were interchangeable, 8 (14) were in the grey zone, and 31 (54) were not interchangeable. Conclusions: Microdialysis with a central venous catheter appears to provide reliable absolute blood lactate values. Although changes in blood lactate measurements showed an excellent concordance rate, changes between the two methods were poorly interchangeable with the TIM. Clinical trial registration: NCT02296593.

Assessment of changes in cardiac index and fluid responsiveness: a comparison of Nexfin and transpulmonary thermodilution.

BACKGROUND: The Nexfin device uses non-invasive photoplethysmography to monitor cardiac output and respiratory variations in pulse pressure and stroke volume. The aim of this study was to compare rapid changes in cardiac index after fluid challenge between Nexfin and bolus transpulmonary thermodilution and the ability to predict fluid responsiveness of dynamic indices given by Nexfin. METHODS: Simultaneous comparative cardiac index were collected from transpulmonary thermodilution and Nexfin before and after fluid challenge in 45 patients following conventional cardiac surgery. Correlations, Bland-Altman analyses and percentage errors were calculated. Pulse pressure variations and stroke volume variations before fluid challenge were collected to assess their discrimination in predicting fluid responsiveness. RESULTS: Eight (18%) patients were excluded. A weak positive relationship was found between rapid changes in cardiac index after fluid challenge given by both technologies (n = 37, r = 0.39, P = 0.019). Bias, precision and limits of agreements were 0.20 l/min/m(2) (95% confidence interval (CI) 0.02-0.40), 0.57 l/min/m(2) and ± 1.12 l/min/m(2) before fluid challenge, and 0.01 l/min/m(2) (95% CI -0.24 to 0.26), 0.74 l/min/m(2) and ± 1.45 l/min/m(2) after fluid challenge. Percentage errors between Nexfin and transpulmonary thermodilution were 55% and 58% before and after fluid challenge, respectively. Pulse pressure variations and stroke volume variations given by Nexfin were not discriminant to predict fluid responsiveness: areas under receiver operating characteristics curves 0.57 (95% CI 0.40-0.73) and 0.50 (0.33-0.67), respectively. CONCLUSIONS: The Nexfin cannot be used to measure rapid changes in cardiac index following fluid challenge and to predict fluid responsiveness after cardiac surgery.

Non-invasive continuous arterial pressure and cardiac index monitoring with Nexfin after cardiac surgery.

BACKGROUND: This observational study was designed to evaluate the reliability and precision of a new digital photoplethysmographic device (Nexfin, BMEYE B.V., Amsterdam, The Netherlands) for continuous and non-invasive assessment of arterial pressure and cardiac output. METHODS: Fifty consecutive adult subjects were prospectively enrolled at admission to the intensive care unit after conventional cardiac surgery and investigated hourly from T0 to T4. Simultaneous comparative systolic, diastolic, and mean arterial pressures and cardiac index (CI) data points were collected from an invasive radial artery catheter, transpulmonary thermodilution catheter, and the Nexfin device. Correlations were determined by linear regression. The Bland-Altman analysis was used to compare bias, precision, and limits of agreement. RESULTS: Six (12%) subjects were excluded from the analysis because of the inability to obtain a reliable photoplethysmographic signal. No complications were observed. A significant relationship was found between absolute values of photoplethysmographic and radial systolic (r(2)=0.56, P<0.001), diastolic (r(2)=0.61, P<0.001), and mean (r(2)=0.77, P<0.001) arterial pressures. A significant relationship was also found between transpulmonary thermodilution and Nexfin CI absolute values (r(2)=0.33, P<0.001). Bias, precision, and limits of agreement between the mean photoplethysmographic and radial arterial pressures were 4.6 (95% confidence interval: 3.7-5.5), 6.5, and -17.3 to 8.1 mm Hg, respectively. The percentage error between transpulmonary thermodilution and the Nexfin for CI measurement was 50%. CONCLUSIONS: The Nexfin device is safe, convenient, and reliable in measuring continuous non-invasive arterial pressure but not interchangeable with transpulmonary thermodilution to monitor CI.

Influence of bacterial resistance on mortality in intensive care units: a registry study from 2000 to 2013 (IICU Study).

BACKGROUND: Bacterial resistance to antibiotics is a daily concern in intensive care units. However, few data are available concerning the clinical consequences of in-vitro-defined resistance. AIM: To compare the mortality of patients with nosocomial infections according to bacterial resistance profiles. METHODS: The prospective surveillance registry in 29 French intensive care units (ICUs) participating during the years 2000-2013 was retrospectively analysed. All patients presenting with a nosocomial infection in ICU were included. FINDINGS: The registry contained 88,000 eligible patients, including 10,001 patients with a nosocomial infection. Among them, 3092 (36.7%) were related to resistant micro-organisms. Gram-negative bacilli exhibited the highest rate of resistance compared to Gram-positive cocci (52.8% vs 48.1%; P < 0.001). In-hospital mortality was higher in cases of patients with antibiotic-resistant infectious agents (51.9% vs 45.5%; P < 0.001), and critical care length of stay was longer (33 ± 26 vs 29 ± 22 days; P < 0.001). These results remained significant after SAPS II matching (P < 0.001) and in the Gram-negative bacilli and Gram-positive cocci subgroups. No difference in mortality was found with respect to origin prior to admission. CONCLUSION: Patients with bacterial resistance had higher ICU mortality and increased length of stay, regardless of the bacterial species or origin of the patient.

[Hypothermia after spinal anaesthesia: implication of morphine?]. / Hypothermie après rachianesthésie: rôle de la morphine?

Spinal anaesthesia is the gold standard for elective caesarean section. This technique presents several adverse effects. We report a severe case of hypothermia (33.3 degrees C) after spinal administration of bupivacaine (10 mg) and morphine (100 microg) for elective caesarean section. After excluding other causes of hypothermia, this one could be explained by both the own effects of local anaesthesia (i.e. peripheral vasodilatation) and by the central effect of intrathecal morphine. Because hypothermia is not predictable after spinal injection of morphine both monitoring of central temperature and active warming of the patients could be proposed. Naloxone has been proposed in a case of hypothermia related to spinal injection of morphine.

Oxidative stress related markers in the "VITA" and the centenarian projects.

Oxidative stress seems to play an important role in the pathophysiology of Alzheimer's disease (AD). At present there are no easily accessible biochemical markers for AD. We performed activity assays for platelet MAO-B and erythrocyte Cu/Zn-SOD as well as Western blotting for these two proteins. Moreover, we assessed plasma lactoferrin and performed RFLP-analysis for the MAO-B-intron-13-polymorphism in patients from the Vienna-Transdanube Aging (VITA) and from the so called centenarian project. The first one, VITA, is a community-based cohort study of all 75 years old inhabitants of a geographical region of Vienna. The centenarian project investigates chronic care in-old patients suffering from AD. In both sexes platelet MAO-B activity increased significantly in the AD group, and Cu/Zn-SOD activity decreased, but the latter effect was significant only in females. No significant difference was found regarding plasma lactoferrin. No correlation was found between MAO-Bi13 and MAO-B platelet activity or allele MAO-Bi13 and disease frequency. These results point to the possibility that a combination of MAO-B and SOD activity levels might be useful tools for an early diagnosis of AD.

Lower limb peripheral NIRS parameters during a vascular occlusion test: an experimental study in healthy volunteers.

OBJECTIVES: The aim of the study was to compare NIRS parameters in combination with a vascular occlusion test (VOT) at a proximal (leg) and a distal (foot) site in male and female. STUDY DESIGN: A prospective experimental study in healthy subjects. PATIENTS AND METHODS: Twenty volunteers (10 male, 10 female, 28 ± 4 years) were investigated during 4 experimental steps: baseline, ischemia, reperfusion, and baseline. For each volunteer, 3 NIRS optodes were placed on right and left calves and the left arch of the foot. Blood pressure, heart rate and peripheral pulse oxymetry were monitored. RESULTS: Significant differences were observed at baseline between regional oxygen saturation (rSO2) values according to the site of measurement (proximal rSO2 81 ± 9% vs distal rSO2 60 ± 5%, P<0.001) but not according to gender. Both decreases in proximal and distal rSO2 during ischemia and increases over baseline values during reperfusion depended on group membership (male or female). NIRS parameters during the VOT were significantly higher in male when compared with female at the proximal site: desaturation rate 5.6% (IQR: 5.5) vs 2.5% (IQR: 0.8), P=0.001; resaturation rate 40.7% (IQR: 6.6) vs 21.7% (IQR: 5.4), P=0.003; and ΔrSO2 10.0% (IQR: 7.0) vs 5.5% (IQR: 6.0), P=0.041. CONCLUSIONS: Values of rSO2 at the lower limb varied according to the anatomical site of measurement. A VOT induced major changes in rSO2 that differed between male and female. These results should be taken into account in further clinical studies.

[Multicenter survey on ventilator-associated pneumonia prevention in intensive care]. / Enquête multicentrique sur l'application des recommandations de prévention des pneumopathies acquises sous ventilation mécanique en réanimation.

OBJECTIVE: Ventilator-associated pneumonia (VAP) is the most common hospital-acquired infection in intensive care unit (ICU). The aim of the study was to evaluate the follow-up of the guidelines for VAP prevention. STUDY DESIGN: Retrospective, observational and multicenter study. PATIENTS AND METHODS: During one year, all patients with mechanical ventilation over 48 hours were included in the CCLIN-Ouest Network. The demographic characteristics of the patients, the use of specific protocol for VAP prevention and the density of incidence of VAP were recorded. The use of a protocol for preventing VAP (absence, incomplete, complete and care bundle (i.e. complete prevention of VAP with weaning mechanical protocol and sedation protocol)) was collected. RESULTS: 26 ICU with 5742 patients were included. Ten ICU (38%; 2595 patients) had no protocol for VAP prevention, eight ICU (31%; 1821 patients) had an incomplete protocol, five ICU (19%; 561 patients) had a complete protocol and three ICU (12%; 765 patients) had a care bundle. The density of incidence of VAP was 14.8‰ (Interquartile range [IQR]: 10.2-0.1) for no protocol group, 15.6‰ [IQR: 12.6-6.2] for incomplete protocol group, 11.0‰ [IQR: 9.1-14.0] for complete protocol group and 12.9‰ [5-7,7-9,9-12] for care bundle group (P=0.742). CONCLUSIONS: The compliance to prevention of VAP was poor. Proposals for improving practice are discussed.

An information campaign on aminoglycosides use during septic shock failed to improve the quality of care.

BACKGROUND: Septic shock remains a major cause of death in intensive care units (ICU) and an inappropriate antibiotic regimen worsens the prognosis. The aim of the study was to assess the impact of an information campaign on modalities of prescription of aminoglycosides in septic shock. STUDY DESIGN: A prospective observational study. METHODS: Consecutive septic shock patients admitted to the surgical ICU over a 2-year period were included. An information campaign allowed to differentiate between a pre- (P1) and a post- (P2) interventional period. The campaign clarified the rules and requirements for pharmacological monitoring of aminoglycosides. The main objective was to increase the rate of prescription of peak serum aminoglycoside following the first intravenous injection. RESULTS: One hundred and forty-eight patients (P1=76 and P2=72) were finally included into the study. Similar clinical characteristics were observed during both periods. The rate of prescription of peak serum aminoglycoside following the first injection was performed in 49% (P1) versus 65% (P2), P=0.09. The length of stay in ICU was 16 days [extremes: 1-74] (P1) versus 17 days [extremes: 1-133] (P2) (P=0.84). Inhospital mortality was 28% (P1) versus 26% (P2), P=0.86. CONCLUSIONS: An information campaign describing the modalities of prescription of aminoglycosides in septic shock failed to improve medical practices and patient outcomes. A mobile team of antibiotics could be useful in daily practice.