Aurélie Birenbaum

Influence of renal dysfunction on the accuracy of procalcitonin for the diagnosis of postoperative infection after vascular surgery.

Objective:Procalcitonin has been advocated as a specific biomarker for bacterial infection. We performed this study to determine whether accuracy of procalcitonin for diagnosis of postoperative bacterial infection is affected by renal function after aortic surgery. Design:Single-center prospective study. Setting:University hospital. Patients:Two hundred seventy-six patients scheduled for elective major aortic surgery. Interventions:Blood samples were taken before surgery and each day over the 5-day postoperative period, and measurement of serum procalcitonin was performed. Diagnosis of infection was performed by a blinded expert panel. Renal function was assessed using an estimate of creatinine clearance with the Cockcroft formulas. Renal dysfunction was defined as a creatinine clearance <50 mL·min−1. Measurements and Main Results:Infection was diagnosed in 67 patients. Seventy five patients (27%) had postoperative renal dysfunction. Procalcitonin was significantly higher in infected patients, with a peak reached at the fourth postoperative day, but it was significantly higher in patients with impaired renal function in both control and infected patients. The optimal threshold of procalcitonin markedly differed in patients with renal dysfunction compared with patients without renal dysfunction (2.57 vs. 0.80 ng·mL−1, p < .05). The diagnostic accuracy of procalcitonin significantly increased (0.74 vs. 0.70, p < .05) when the threshold of procalcitonin was adapted to the renal function. The elevation of procalcitonin occurred 2 days before the medical team was able to diagnose infection. Conclusions:Procalcitonin is a valuable marker of bacterial infections after major aortic surgery, but renal function is a major determinant of procalcitonin levels and thus different thresholds should be applied according to renal function impairment.

Comparison of Plastic Single-use and Metal Reusable Laryngoscope Blades for Orotracheal Intubation during Rapid Sequence Induction of Anesthesia

Background:Plastic single-use laryngoscope blades are inexpensive and carry a lower risk of infection compared with metal reusable blades, but their efficiency during rapid sequence induction remains a matter of debate. The authors therefore compared plastic and metal blades during rapid sequence induction in a prospective randomized trial. Methods:Two hundred eighty-four adult patients undergoing general anesthesia requiring rapid sequence induction were randomly assigned on a weekly basis to either plastic single-use or reusable metal blades (cluster randomization). After induction, a 60-s period was allowed to complete intubation. In the case of failed intubation, a second attempt was performed using metal blade. The primary endpoint of the study was the rate of failed intubations, and the secondary endpoint was the incidence of complications (oxygen desaturation, lung aspiration, and oropharynx trauma). Results:Both groups were similar in their main characteristics, including risk factors for difficult intubation. On the first attempt, the rate of failed intubation was significantly increased in plastic blade group (17 vs. 3%; P < 0.01). In metal blade group, 50% of failed intubations were still difficult after the second attempt. In plastic blade group, all initial failed intubations were successfully intubated using metal blade, with an improvement in Cormack and Lehane grade. There was a significant increase in the complication rate in plastic group (15 vs. 6%; P < 0.05). Conclusions:In rapid sequence induction of anesthesia, the plastic laryngoscope blade is less efficient than a metal blade and thus should not be recommended for use in this clinical setting.

Involvement of beta 3-adrenoceptor in altered beta-adrenergic response in senescent heart: role of nitric oxide synthase 1-derived nitric oxide.

Background:In senescent heart, β-adrenergic response is altered in parallel with β1- and β2-adrenoceptor down-regulation. A negative inotropic effect of β3-adrenoceptor could be involved. In this study, the authors tested the hypothesis that β3-adrenoceptor plays a role in β-adrenergic dysfunction in senescent heart. Methods:β-Adrenergic responses were investigated in vivo (echocardiography–dobutamine, electron paramagnetic resonance) and in vitro (isolated left ventricular papillary muscle, electron paramagnetic resonance) in young adult (3-month-old) and senescent (24-month-old) rats. Nitric oxide synthase (NOS) immunolabeling (confocal microscopy), nitric oxide production (electron paramagnetic resonance) and β-adrenoceptor Western blots were performed in vitro. Data are mean percentages of baseline ± SD. Results:An impaired positive inotropic effect (isoproterenol) was confirmed in senescent hearts in vivo (117 ± 23 vs. 162 ± 16%; P < 0.05) and in vitro (127 ± 10 vs. 179 ± 15%; P < 0.05). In the young adult group, the positive inotropic effect was not significantly modified by the nonselective NOS inhibitor NG-nitro-l-arginine methylester (l-NAME; 183 ± 19%), the selective NOS1 inhibitor vinyl-l-N-5(1-imino-3-butenyl)-l-ornithine (l-VNIO; 172 ± 13%), or the selective NOS2 inhibitor 1400W (183 ± 19%). In the senescent group, in parallel with β3-adrenoceptor up-regulation and increased nitric oxide production, the positive inotropic effect was partially restored by l-NAME (151 ± 8%; P < 0.05) and l-VNIO (149 ± 7%; P < 0.05) but not by 1400W (132 ± 11%; not significant). The positive inotropic effect induced by dibutyryl-cyclic adenosine monophosphate was decreased in the senescent group with the specific β3-adrenoceptor agonist BRL 37344 (167 ± 10 vs. 142 ± 10%; P < 0.05). NOS1 and NOS2 were significantly up-regulated in the senescent rat. Conclusions:In senescent cardiomyopathy, β3-adrenoceptor overexpression plays an important role in the altered β-adrenergic response via induction of NOS1-nitric oxide.

Preservation of the Positive Lusitropic Effect of β-adrenoceptors Stimulation in Diabetic Cardiomyopathy

BACKGROUND: In diabetic cardiomyopathy, diastolic dysfunction results in part from sarcoplasmic reticulum abnormalities affecting both phospholamban and sarcoplasmic reticulum Ca2+ uptake (SERCA2a). Consequently, the positive lusitropic effect of &bgr;-adrenoceptors stimulation could be altered, and &bgr;3-adrenoceptor over-expression may play a role, as previously demonstrated with an altered positive inotropic effect. In this study, we tested the hypothesis that the &bgr;-adrenergic positive lusitropic effect is altered in diabetic cardiomyopathy, and that &bgr;3-adrenoceptor over-expression is involved. METHODS: &bgr;-adrenergic responses were investigated in vivo (dobutamine-echocardiography) and in vitro (papillary muscle preparation) in healthy and diabetic rats killed 4 (4W) and 12 (12W) wk after IV streptozotocin injection. The effect of &bgr;3-adrenoceptor pathway inhibition by S-cyanopindolol (selective &bgr;3-adrenoceptor antagonist) or by NG-nitro-l-arginine-methyl-ester (nonselective nitric oxide synthase inhibitor) on the lusitropic response to isoproterenol (nonselective &bgr;-adrenoceptors agonist) was studied in vitro. Western blots were performed to quantify the protein expressions of &bgr;1- and &bgr;3-adrenoceptors, phospholamban, and SERCA2a. Data are presented as mean percentages of baseline ± sd. RESULTS: Despite the increased phospholamban/SERCA2a protein ratio and documented diastolic dysfunction, the positive lusitropic effect of &bgr;-adrenoceptors stimulation was preserved in vivo (dobutamine) and in vitro (isoproterenol) in 4W and 12W diabetic, compared with healthy, rats. The &bgr;3-adrenoceptor was up-regulated whereas &bgr;1-adrenoceptor was down-regulated in 4W and 12W diabetic, compared with healthy, rats. Nevertheless, S-cyanopindolol or NG-nitro-l-arginine-methyl-ester had no lusitropic effect. CONCLUSIONS: The positive lusitropic effect of &bgr;-adrenoceptor stimulation was preserved in diabetic cardiomyopathy. &bgr;3-adrenoceptor over-expression does not seem to affect this process.

Effect of Cricoid Pressure Compared With a Sham Procedure in the Rapid Sequence Induction of Anesthesia: The IRIS Randomized Clinical Trial

Importance The use of cricoid pressure (Sellick maneuver) during rapid sequence induction (RSI) of anesthesia remains controversial in the absence of a large randomized trial. Objective To test the hypothesis that the incidence of pulmonary aspiration is not increased when cricoid pressure is not performed. Design, Setting, and Participants Randomized, double-blind, noninferiority trial conducted in 10 academic centers. Patients undergoing anesthesia with RSI were enrolled from February 2014 until February 2017 and followed up for 28 days or until hospital discharge (last follow-up, February 8, 2017). Interventions Patients were assigned to a cricoid pressure (Sellick group) or a sham procedure group. Main Outcomes and Measures Primary end point was the incidence of pulmonary aspiration (at the glottis level during laryngoscopy or by tracheal aspiration after intubation). It was hypothesized that the sham procedure would not be inferior to the cricoid pressure. The secondary end points were related to pulmonary aspiration, difficult tracheal intubation, and traumatic complications owing to the tracheal intubation or cricoid pressure. Results Of 3472 patients randomized, mean (SD) age was 51 (19) years and 1777 (51%) were men. The primary end point, pulmonary aspiration, occurred in 10 patients (0.6%) in the Sellick group and in 9 patients (0.5%) in the sham group. The upper limit of the 1-sided 95% CI of relative risk was 2.00, exceeding 1.50, failing to demonstrate noninferiority (P = .14). The risk difference was −0.06% (2-sided 95% CI, −0.57 to 0.42) in the intent-to-treat population and −0.06% (2-sided 95% CI, −0.56 to 0.43) in the per protocol population. Secondary end points were not significantly different among the 2 groups (pneumonia, length of stay, and mortality), although the comparison of the Cormack and Lehane grade (Grades 3 and 4, 10% vs 5%; P <.001) and the longer intubation time (Intubation time >30 seconds, 47% vs 40%; P <.001) suggest an increased difficulty of tracheal intubation in the Sellick group. Conclusions and Relevance This large randomized clinical trial performed in patients undergoing anesthesia with RSI failed to demonstrate the noninferiority of the sham procedure in preventing pulmonary aspiration. Further studies are required in pregnant women and outside the operating room. Trial Registration ClinicalTrials.gov Identifier: NCT02080754

Atorvastatin reduces β-Adrenergic dysfunction in rats with diabetic cardiomyopathy

Background In the diabetic heart the β-adrenergic response is altered partly by down-regulation of the β1-adrenoceptor, reducing its positive inotropic effect and up-regulation of the β3-adrenoceptor, increasing its negative inotropic effect. Statins have clinical benefits on morbidity and mortality in diabetic patients which are attributed to their “pleiotropic” effects. The objective of our study was to investigate the role of statin treatment on β-adrenergic dysfunction in diabetic rat cardiomyocytes. Methods β-adrenergic responses were investigated in vivo (echocardiography) and ex vivo (left ventricular papillary muscles) in healthy and streptozotocin-induced diabetic rats, who were pre-treated or not by oral atorvastatin over 15 days (50 mg.kg-1.day-1). Micro-array analysis and immunoblotting were performed in left ventricular homogenates. Data are presented as mean percentage of baseline ± SD. Results Atorvastatin restored the impaired positive inotropic effect of β-adrenergic stimulation in diabetic hearts compared with healthy hearts both in vivo and ex vivo but did not suppress the diastolic dysfunction of diabetes. Atorvastatin changed the RNA expression of 9 genes in the β-adrenergic pathway and corrected the protein expression of β1-adrenoceptor and β1/β3-adrenoceptor ratio, and multidrug resistance protein 4 (MRP4). Nitric oxide synthase (NOS) inhibition abolished the beneficial effects of atorvastatin on the β-adrenoceptor response. Conclusions Atorvastatin restored the positive inotropic effect of the β-adrenoceptor stimulation in diabetic cardiomyopathy. This effect is mediated by multiple modifications in expression of proteins in the β-adrenergic signaling pathway, particularly through the NOS pathway.

Cathéters sciatiques: une alternative analgésique chez les patients diabétiques@@@Sciatic perineural catheters: an alternative analgesia for diabetic patients

Patients with diabetes mellitus have chronic neuropathic pain. The aim of our study was to 1) evaluate the feasibility of providing analgesia with a long-term sciatic perineural catheter in a medical unit for diabetic patients and 2) evaluate its effectiveness. A prospective, monocentric, non-randomized study was conducted over two years. All diabetic patients with an ineffective optimal systemic treatment were included. Written consent was obtained. Popliteal-sciatic nerve catheters were inserted under ultrasound guidance; ropivacaine was started. The primary endpoint was pain at Day 2. Pain intensity was measured using a numeric rating scale (NRS). Secondary endpoints were patient’s pain relief, the impact on quality of life, and morphine consumption, evaluated at Day 0, Day 2, at the time of catheter removal, and one month after catheter removal. Feasibility was evaluated over one year. Fifty-five perineural catheters were placed in 32 patients. The median duration of catheter placement across patients was 13 [4-23] days. No toxic or infectious complications were seen. Effectiveness was evaluated during the second year of the study. Seventeen catheters were placed in 12 patients; 83% of patients had a NRS score ≤3 at Day 2. More than 70% of patients experienced pain relief while the catheter was in place and at one month after its removal. The impact on quality of life was negligible. Morphine consumption was less on Day 2, at the time of catheter removal and one month after removal. The use of sciatic perineural catheters as an alternative analgesia technique in a non-surgical environment for diabetic patients with chronic pain was possible and effective.

Cathéters sciatiques: une alternative analgésique chez les patients diabétiques

Patients with diabetes mellitus have chronic neuropathic pain. The aim of our study was to 1) evaluate the feasibility of providing analgesia with a long-term sciatic perineural catheter in a medical unit for diabetic patients and 2) evaluate its effectiveness. A prospective, monocentric, non-randomized study was conducted over two years. All diabetic patients with an ineffective optimal systemic treatment were included. Written consent was obtained. Popliteal-sciatic nerve catheters were inserted under ultrasound guidance; ropivacaine was started. The primary endpoint was pain at Day 2. Pain intensity was measured using a numeric rating scale (NRS). Secondary endpoints were patient’s pain relief, the impact on quality of life, and morphine consumption, evaluated at Day 0, Day 2, at the time of catheter removal, and one month after catheter removal. Feasibility was evaluated over one year. Fifty-five perineural catheters were placed in 32 patients. The median duration of catheter placement across patients was 13 [4-23] days. No toxic or infectious complications were seen. Effectiveness was evaluated during the second year of the study. Seventeen catheters were placed in 12 patients; 83% of patients had a NRS score ≤3 at Day 2. More than 70% of patients experienced pain relief while the catheter was in place and at one month after its removal. The impact on quality of life was negligible. Morphine consumption was less on Day 2, at the time of catheter removal and one month after removal. The use of sciatic perineural catheters as an alternative analgesia technique in a non-surgical environment for diabetic patients with chronic pain was possible and effective.

Last updates about amniotic fluid embolism and a case report

Amniotic fluid embolism (AFE) is a rare complication of pregnancy, which, in France, is the second leading cause of maternal mortality. It results from the passage of amniotic fluid into the maternal circulation, but mechanisms leading to clinical signs are not yet clearly identified. After a literature review, we report on the case of a 34 years old patient occurred during labor. Laboratory tests were performed during acute phase to diagnose coagulopathy and to monitor vital parameters. Further laboratory tests were conducted to support the diagnosis: cytology, study of insulin-like growth factor-binding protein 1, tryptase and alpha-foetoprotein. Performances and place of these laboratory tests must be precised as no specific test can attest the diagnosis.