Impact of increasing post-filter ionized calcium target on filter lifespan in renal replacement therapy with regional citrate anticoagulation: A before-and-after study.

INTRODUCTION: Regional citrate anticoagulation (RCA) is the recommended method for anticoagulation in continuous renal replacement therapy (CRRT). However, the optimal post-filter ionized calcium (iCa) target level remains unclear. This study aims to assess the effect of increasing the post-filter iCa target level from 0.25-0.35 mmol/L to 0.30-0.40 mmol/L on filter lifespan until clotting during RCA-CRRT. METHODS: This before-and-after single-center study included patients who underwent RCA-CRRT sessions without systemic anticoagulation during two periods. The first period included patients with a post-filter iCa target between 0.25 and 0.35 mmol/L, while the second period included those with a target between 0.30 and 0.40 mmol/L. The primary outcome was filter lifespan until clotting. RESULTS: A total of 1037 CRRT sessions were analyzed, with 610 sessions in the first period and 427 sessions in the second period. After adjusting for confounding factors, there was no significant difference in filter lifespan until clotting between the two groups (hazard ratio, 1.020 [0.703; 1.481]; p = 0.92). CONCLUSION: Increasing the post-filter iCa target level from 0.25-0.35 mmol/L to 0.30-0.40 mmol/L during RCA-CRRT does not reduce filter lifespan until clotting and may decrease unnecessary citrate exposure. However, the optimal post-filter iCa target should be individualized according to the patient's clinical and biological status.

High-flow oxygen therapy versus facemask preoxygenation in anticipated difficult airway management (PREOPTI-DAM): an open-label, single-centre, randomised controlled phase 3 trial.

Background: Difficult airway management remains a critical procedure with life-threatening adverse events. Current guidelines suggest high-flow therapy by nasal cannulae (HFNC) as a preoxygenation device in this setting. However, there is an evidence gap to support this recommendation. Methods: The PREOPTI-DAM study is an open-label, single-centre, randomised controlled phase 3 trial done at Nantes University Hospital, France. Patients were aged 18-90 years with one major or two minor criteria of anticipated difficult airway management, and requiring intubation for scheduled surgery, were eligible. Patients with body mass index >35 kg/m2 were excluded. Patients were randomly allocated (1:1) to receive 4-min preoxygenation by HFNC or facemask. Randomisation was stratified according to the intubation strategy (laryngoscopic versus fiberoptic intubation). The primary outcome was the incidence of oxygen desaturation ≤94% or of bag-mask ventilation during intubation. The primary and safety analyses included the intention to treat population. This trial is registered with ClinicalTrials.gov (NCT03604120) and EudraCT (2018-A00434-51). Findings: From September 4 2018 to March 31 2021, 186 patients were enrolled and randomly assigned. One participant withdrew consent and 185 (99.5%) were included in the primary analysis (HFNC, N = 95; Facemask, N = 90). The incidence of the primary outcome was not significantly different between the HFNC and the facemask groups, respectively 2 (2%) versus 7 (8%); adjusted difference, -5.6 [95% confidence interval (CI), -11.8 to 0.6], P = 0.10. In the HFNC group, 76 patients (80%) versus 53 (59%) in the facemask group, reported good or excellent intubation experiences; adjusted difference 20.5 [95% CI, 8.3-32.8], P = 0.016. Comparing HFNC with facemask, severe complication occurred in 22 (23%) versus 27 (30%) patients (P = 0.29), and moderate complication in 14 (15%) versus 18 (20%) patients (P = 0.35). No death or cardiac arrest occurred during the study. Interpretation: Compared with facemask, HFNC did not significantly reduce the incidence of desaturation ≤94% or bag-mask ventilation during anticipated difficult intubation but the trial was underpowered to rule out a clinically significant benefit. Patient satisfaction was improved with HFNC. Funding: Nantes University Hospital and Fisher & Paykel Healthcare.

Lung Ultrasound in Emergency and Critically Ill Patients: Number of Supervised Exams to Reach Basic Competence.

BACKGROUND: Lung ultrasound is increasingly used in critically ill patients as an alternative to bedside chest radiography, but the best training method remains uncertain. This study describes a training curriculum allowing trainees to acquire basic competence. METHODS: This multicenter, prospective, and educational study was conducted in 10 Intensive Care Units in Brazil, China, France and Uruguay. One hundred residents, respiratory therapists, and critical care physicians without expertise in transthoracic ultrasound (trainees) were trained by 18 experts. The main study objective was to determine the number of supervised exams required to get the basic competence, defined as the trainees' ability to adequately classify lung regions with normal aeration, interstitial-alveolar syndrome, and lung consolidation. An initial 2-h video lecture provided the rationale for image formation and described the ultrasound patterns commonly observed in critically ill and emergency patients. Each trainee performed 25 bedside ultrasound examinations supervised by an expert. The progression in competence was assessed every five supervised examinations. In a new patient, 12 pulmonary regions were independently classified by the trainee and the expert. RESULTS: Progression in competence was derived from the analysis of 7,330 lung regions in 2,562 critically ill and emergency patients. After 25 supervised examinations, 80% of lung regions were adequately classified by trainees. The ultrasound examination mean duration was 8 to 10 min in experts and decreased from 19 to 12 min in trainees (after 5 vs. 25 supervised examinations). The median training duration was 52 (42, 82) days. CONCLUSIONS: A training curriculum including 25 transthoracic ultrasound examinations supervised by an expert provides the basic skills for diagnosing normal lung aeration, interstitial-alveolar syndrome, and consolidation in emergency and critically ill patients.

Colour Doppler ultrasound after major cardiac surgery improves diagnostic accuracy of the pulmonary infection score in acute respiratory failure: A prospective observational study.

BACKGROUND: Postoperative pneumonia is a frequent complication after cardiac surgery, and its diagnosis is difficult. Little is known about the diagnostic accuracy of lung ultrasound (LUS) in the detection of pneumonia in cardiac surgical patients. The substitution of chest radiography by colour Doppler LUS (LUS-sCPIS) in the simplified clinical pulmonary infection score (sCPIS) could improve the diagnosis of pneumonia following cardiac surgery. OBJECTIVE: The aim of this study was to compare the diagnostic accuracy of LUS-sCPIS and of sCPIS alone in the detection of postoperative pneumonia after cardiac surgery. DESIGN: A prospective study of diagnostic accuracy. SETTING: A Surgical Intensive Care Unit of a French University Hospital. PATIENTS: Fifty-one patients with acute respiratory failure within 72 h after cardiac surgery were enrolled between January and May 2015. MAIN OUTCOME MEASURE: The two index tests, LUS-sCPIS and sCPIS, were calculated for all patients at the onset of acute respiratory failure. The reference standard for the diagnosis of pneumonia was based on the consensus of three physicians, blind to the sCPIS and LUS-sCPIS data, based on a posthoc review of all the clinical, radiological and microbiological evidence. The diagnostic accuracy of LUS-sCPIS was compared with that of sCPIS in the detection of postoperative pneumonia. RESULTS: Pneumonia was diagnosed in 26 out of 51 patients. The LUS-sCPIS detected the presence of pneumonia with a sensitivity of 92% (95% CI 0.85 to 0.99) and a specificity of 68% (95% CI 0.55 to 0.81). The sCPIS detected the presence of pneumonia with a sensitivity of 35% (95% CI 0.22 to 0.48) and a specificity of 84% (95% CI 0.74 to 0.94). The area under the curve (AUC) of LUS-sCPIS at 0.80 (95% CI 0.69 to 0.91) was higher than the AUC of sCPIS at 0.59 (95% CI 0.47 to 0.71; P = 0.0008). CONCLUSION: Compared with sCPIS, LUS-sCPIS improved diagnostic accuracy in the detection of postoperative pneumonia in patients with acute respiratory failure after cardiac surgery. It could be a useful bedside tool to guide pneumonia management. TRIAL REGISTRATION: Clinicaltrials.gov identifier: NCT03279887.

Emergency Abdominal Surgery Outcomes of Critically Ill Patients on Extracorporeal Membrane Oxygenation: A Case-Matched Study with a Propensity Score Analysis.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) induces coagulation disorders increasing the risk of bleeding during invasive procedures. We aimed to describe the outcomes of critically ill ECMO patients undergoing emergency abdominal surgery compared to non-ECMO patients. STUDY DESIGN: This is a retrospective case-matched single-center study with propensity score analysis in a tertiary ICU. All patients who underwent abdominal surgery were included. RESULTS: From 2006 to 2014, 77 patients admitted in our ICU underwent emergency abdominal surgery, 35 were on ECMO. Surgery indications were comparable for ECMO and non-ECMO patients: mostly intestinal ischemia (42%) and cholecystectomy (25%). Postoperative bleeding was significantly more frequent in ECMO group versus non-ECMO: 77% versus 40% transfused, with medians of 13 (6-22) versus 3 (0-5) packed red blood cell; 9 (3-17) versus 0 (0-4) fresh frozen plasma and 12 (3-22) versus 0 (0-8) platelet units (p < 0.001 for all items). Reintervention for hemorrhage was required in 20% versus 2%, respectively, p = 0.02. At multivariable analysis, ECMO was strongly associated with bleeding (OR, 5.6 [95% CI, 2.0-15.4]; p = 0.001). ICU mortality was higher for ECMO-treated patients (69% vs. 33%; p = 0.003), but perioperative mortality remained comparable between groups (11% vs. 12%, NS). Propensity score-matched analysis confirmed more frequent and severe bleeding in ECMO patients. CONCLUSIONS: Abdominal surgery procedures on ECMO-treated patients are associated with a higher risk of hemorrhage compared to non-ECMO ICU patients. Further studies are needed to optimize ECMO patient management during such interventions.

Modification of Tracheal Cuff Shape and Continuous Cuff Pressure Control to Prevent Microaspiration in an Ex Vivo Pig Tracheal Two-Lung Model.

OBJECTIVES: Microaspiration of subglottic secretions plays a pivotal role in ventilator-associated pneumonia. Impact of endotracheal tube cuff material and shape on tracheal sealing performance remains debated. The primary objective was to compare the tracheal sealing performance of polyvinyl chloride tapered, cylindrical and spherical cuffs. Secondary objectives were to determine the impact of continuous cuff pressure control on sealing performance and pressure variability. DESIGN: Prospective randomized ex vivo animal study. SETTING: French research laboratory. SUBJECTS: Seventy-two ex vivo pig tracheal two-lung blocks. INTERVENTIONS: Blocks were randomly intubated with cylindrical (n = 26), tapered (n = 24), or spherical (n = 22) polyvinyl chloride endotracheal tube cuffs. Two milliliter of methylene blue were instilled above the cuff to quantify microaspirations, and lungs were ventilated for 2 hours. Continuous cuff pressure control was implemented in 33 blocks. MEASUREMENTS AND MAIN RESULTS: Cuff pressures were continuously recorded, and after 2 hours, a microaspiration score was calculated. Tapered cuffs improved cuff sealing performance compared with spherical cuffs with or without continuous cuff pressure control. Compared with spherical cuffs, tapered cuffs reduced the microaspiration score without and with continuous pressure control by 65% and 72%, respectively. Continuous cuff pressure control did not impact sealing performance. Tapered cuffs generated higher cuff pressures and increased the time spent with overinflation compared with spherical cuffs (median [interquartile range], 77.9% [0-99.8] vs. 0% [0-0.5]; p = 0.03). Continuous cuff pressure control reduced the variability of tapered and spherical cuffs likewise the time spent with overinflation of tapered and cylindrical cuffs. CONCLUSIONS: Polyvinyl chloride tapered cuffs sealing enhanced performance at the cost of an increase in cuff pressure and in time spent with overinflation. Continuous cuff pressure control reduced the variability and normalized cuff pressures without impacting sealing performance.

Tapered-cuff Endotracheal Tube Does Not Prevent Early Postoperative Pneumonia Compared with Spherical-cuff Endotracheal Tube after Major Vascular Surgery: A Randomized Controlled Trial.

BACKGROUND: Patients undergoing major vascular surgery often develop postoperative pneumonia that impacts their outcomes. Conflicting data exist concerning the potential benefit of tapered-shaped cuffs on tracheal sealing. The primary objective of this study was to assess the efficiency of a polyvinyl chloride tapered-cuff endotracheal tube at reducing the postoperative pneumonia rate after major vascular surgery. Secondary objectives were to determine its impact on microaspiration, ventilator-associated pneumonia rate, and inner cuff pressure. METHODS: This prospective randomized controlled study included 109 patients who were randomly assigned to receive either spherical- (standard cuff) or taper-shaped (tapered cuff) endotracheal tubes inserted after anesthesia induction and then admitted to the intensive care unit after major vascular surgery. Cuff pressure was continuously recorded over 5 h. Pepsin and α-amylase concentrations in tracheal aspirates were quantified on postoperative days 1 and 2. The primary outcome was the early postoperative pneumonia frequency. RESULTS: Comparing the tapered-cuff with standard-cuff group, respectively, postoperative pneumonia rates were comparable (42 vs. 44%, P = 0.87) and the percentage (interquartile range) of cuff-pressure time with overinflation was significantly higher (16.1% [1.5 to 50] vs. 0.6% [0 to 8.3], P = 0.01), with a 2.5-fold higher coefficient of variation (20.2 [10.6 to 29.4] vs. 7.6 [6.2 to 10.2], P < 0.001). Although microaspiration frequencies were high, they did not differ between groups. CONCLUSION: For major vascular surgery patients, polyvinyl chloride tapered-cuff endotracheal tubes with intermittent cuff-pressure control did not lower the early postoperative pneumonia frequency and did not prevent microaspiration.

Effect of simulation training on compliance with difficult airway management algorithms, technical ability, and skills retention for emergency cricothyrotomy.

BACKGROUND: The effectiveness of simulation is rarely evaluated. The aim of this study was to assess the impact of a short training course on the ability of anesthesiology residents to comply with current difficult airway management guidelines. METHODS: Twenty-seven third-year anesthesiology residents were assessed on a simulator in a "can't intubate, can't ventilate" scenario before the training (the pretest) and then randomly 3, 6, or 12 months after training (the posttest). The scenario was built so that the resident was prompted to perform a cricothyrotomy. Compliance with airway management guidelines and the cricothyrotomy's duration and technical quality were assessed as a checklist score [0 to 10] and a global rating scale [7 to 35]. RESULTS: After training, all 27 residents (100%) complied with the airway management guidelines, compared with 17 (63%) in the pretest (P < 0.005). In the pretest and the 3-, 6-, and 12-month posttests, the median [range] duration of cricothyrotomy was respectively 117 s [70 to 184], 69 s [43 to 97], 52 s [43 to 76], and 62 s [43 to 74] (P < 0.0001 vs. in the pretest), the median [range] checklist score was 3 [0 to 7], 10 [8 to 10], 9 [6 to 10], and 9 [4 to 10] (P < 0.0001 vs. in the pretest) and the median [range] global rating scale was 12 [7 to 22], 30 [20 to 35], 33 [23 to 35], and 31 [18 to 33] (P < 0.0001 vs. in the pretest). There were no significant differences between performance levels achieved in the 3-, 6-, and 12-month posttests. CONCLUSION: The training session significantly improved the residents' compliance with guidelines and their performance of cricothyrotomy.

Impact of non-dialysis chronic kidney disease on survival in patients with septic shock.

BACKGROUND: Chronic kidney disease (CKD) is known to expose the patient to a high risk of death due to cardiovascular and infective causes. In parallel, septic shock is a major challenge for cardiovascular and immune system. Therefore we tried to determine whether non-dialysis CKD, defined as a baseline estimated glomerular filtration rate (eGFR) <60 ml/min/1.73 m2, for three months prior to the onset of septic shock is an independent risk factor for death. METHODS: All patients treated in a teaching hospital medical ICU for septic shock between January 2007 and December 2009 were retrospectively analyzed. Patients in whom baseline eGFR could not be determined (n=14) or patients treated by chronic dialysis (n=21) or kidney transplantation (n=14) were excluded. A total of 163 patients were included. The population was divided according to baseline eGFR ≥ 60 ml/min/1.73 m2 (non-CKD group, n=107) and < 60 ml/min/1.73 m2 (CKD group, n=56). Twenty-eight-day and 1-year survival curves were plotted. Prognostic factors were determined using Cox proportional hazards models. RESULTS: Baseline eGFR was significantly higher in the non-CKD group than in the CKD group (81 (67-108) vs. 36 (28-44) ml/min/1.73 m2, respectively; p=0.001). Age, SAPS II, serum creatinine on admission and the number of patients with a history of diabetes, hypertension, heart failure, peripheral artery disease, coronary artery disease and statin medication were significantly higher in the CKD group than in the non-CKD group. The mortality rate was lower in the non-CKD group than in the CKD group after 28 days (50% vs. 70%, respectively; p=0.03) and 1 year (64% vs. 82%, respectively; p=0.03). On multivariate analysis, the dichotomous variable CKD (eGFR < 60 ml/min/1.73 m2) remained significantly associated with the 28-day and 1-year mortality. CONCLUSIONS: Non-dialysis CKD appears to be an independent risk factor for death after septic shock.