NButGT Reinforces the Beneficial Effects of Epinephrine on Cardiac Mitochondrial Respiration, Lactatemia and Cardiac Output in Experimental Anaphylactic Shock.

Anaphylactic shock (AS) is the most severe form of acute systemic hypersensitivity reaction. Although epinephrine can restore patients' hemodynamics, it might also be harmful, supporting the need for adjuvant treatment. We therefore investigated whether NButGT, enhancing O-GlcNAcylation and showing beneficial effects in acute heart failure might improve AS therapy. Ovalbumin-sensitized rats were randomly allocated to six groups: control (CON), shock (AS), shock treated with NButGT alone before (AS+pre-Nbut) or after (AS+post-Nbut) AS onset, shock treated with epinephrine alone (AS+EPI) and shock group treated with combination of epinephrine and NButGT (AS+EPI+preNBut). Induction of shock was performed with an intravenous (IV) ovalbumin. Cardiac protein and cycling enzymes O-GlcNAcylation levels, mean arterial pressure (MAP), heart rate, cardiac output (CO), left ventricle shortening fraction (LVSF), mitochondrial respiration, and lactatemia were evaluated using Western blotting experiments, invasive arterial monitoring, echocardiography, mitochondrial oximetry and arterial blood samples. AS decreased MAP (-77%, p < 0.001), CO (-90%, p < 0.001) and LVSF (-30%, p < 0.05). Epinephrine improved these parameters and, in particular, rats did not die in 15 min. But, cardiac mitochondrial respiration remained impaired (complexes I + II -29%, p < 0.05 and II -40%, p < 0.001) with hyperlactatemia. NButGT pretreatment (AS+pre-Nbut) efficiently increased cardiac O-GlcNAcylation level as compared to the AS+post-Nbut group. Compared to epinephrine alone, the adjunction of NButGT significantly improved CO, LVSF and mitochondrial respiration. MAP was not significantly increased but lactatemia decreased more markedly. Pretreatment with NButGT increases O-GlcNAcylation of cardiac proteins and has an additive effect on epinephrine, improving cardiac output and mitochondrial respiration and decreasing blood lactate levels. This new therapy might be useful when the risk of AS cannot be avoided.

Liberal or Conservative Oxygen Therapy for Acute Respiratory Distress Syndrome.

BACKGROUND: In patients with acute respiratory distress syndrome (ARDS), the National Heart, Lung, and Blood Institute ARDS Clinical Trials Network recommends a target partial pressure of arterial oxygen (Pao2) between 55 and 80 mm Hg. Prospective validation of this range in patients with ARDS is lacking. We hypothesized that targeting the lower limit of this range would improve outcomes in patients with ARDS. METHODS: In this multicenter, randomized trial, we assigned patients with ARDS to receive either conservative oxygen therapy (target Pao2, 55 to 70 mm Hg; oxygen saturation as measured by pulse oximetry [Spo2], 88 to 92%) or liberal oxygen therapy (target Pao2, 90 to 105 mm Hg; Spo2, ≥96%) for 7 days. The same mechanical-ventilation strategies were used in both groups. The primary outcome was death from any cause at 28 days. RESULTS: After the enrollment of 205 patients, the trial was prematurely stopped by the data and safety monitoring board because of safety concerns and a low likelihood of a significant difference between the two groups in the primary outcome. Four patients who did not meet the eligibility criteria were excluded. At day 28, a total of 34 of 99 patients (34.3%) in the conservative-oxygen group and 27 of 102 patients (26.5%) in the liberal-oxygen group had died (difference, 7.8 percentage points; 95% confidence interval [CI], -4.8 to 20.6). At day 90, 44.4% of the patients in the conservative-oxygen group and 30.4% of the patients in the liberal-oxygen group had died (difference, 14.0 percentage points; 95% CI, 0.7 to 27.2). Five mesenteric ischemic events occurred in the conservative-oxygen group. CONCLUSIONS: Among patients with ARDS, early exposure to a conservative-oxygenation strategy with a Pao2 between 55 and 70 mm Hg did not increase survival at 28 days. (Funded by the French Ministry of Health; LOCO2 ClinicalTrials.gov number, NCT02713451.).

Mortality and Delays of Management of Acute Mesenteric Ischemia: The Need of a Dedicated Program.

BACKGROUND: To study the mortality and delays of management of patients with acute mesenteric ischemia (AMI) admitted to the emergency department of a tertiary hospital and identify risk factors for 1-month mortality. METHODS: A single-center and retrospective study including all consecutive patients treated for AMI from January 2008 to December 2018 was conducted. Short- and medium-term survival was studied with a Kaplan-Meier analysis. Delays before diagnosis and surgical intervention were collected. To determine factors associated with mortality at 1 month postoperatively, univariate and multivariate analyzes were performed. RESULTS: The survival rate of the 67 included patients was 55.22% at 1 month and 37.31% at 1 year. In-hospital mortality was 50.74%. The average delay between admission and diagnosis was 4.83 ± 5.03 hr (95% confidence interval [CI], 3.60-6.05), and the delay between admission and surgical treatment was 10.64 ± 8.80 hr (95% CI, 8.49-12.79). The independent variables associated with an increased mortality at 1 month postoperatively in the univariate analysis were age >65 years old (odds ratio [OR] = 3.52; P = 0.046), lactate >3.31 mmol/l at admission (H0) (OR = 7.38; P < 0.001), lactate >3.32 mmol/l on day 1 (H24) (OR = 5.60; P = 0.002), creatinine >95.9 µmol/l at H0 (OR = 4.66; P = 0.004), aspartate aminotransferase (AST) >59 U/l at H0 (OR = 3.55; P = 0.017), and having hypertension as comorbidity (OR = 9.32; P = 0.040). Early curative anticoagulation (z = -2.4; P = 0.016) was an independent protective factor for mortality, and lactate >3.31 mmol/l at H0 (z = 2.62; P = 0.009) was an independent predictor factor of mortality at 1 month postoperatively in the multivariate analysis. CONCLUSION: AMI remains a serious and lethal condition with delays of surgical management remaining too long due to a lack of a dedicated therapeutic protocol allowing an early diagnosis.

Cerebral perfusion using ASL in patients with COVID-19 and neurological manifestations: A retrospective multicenter observational study.

BACKGROUND AND PURPOSE: Cerebral hypoperfusion has been reported in patients with COVID-19 and neurological manifestations in small cohorts. We aimed to systematically assess changes in cerebral perfusion in a cohort of 59 of these patients, with or without abnormalities on morphological MRI sequences. METHODS: Patients with biologically-confirmed COVID-19 and neurological manifestations undergoing a brain MRI with technically adequate arterial spin labeling (ASL) perfusion were included in this retrospective multicenter study. ASL maps were jointly reviewed by two readers blinded to clinical data. They assessed abnormal perfusion in four regions of interest in each brain hemisphere: frontal lobe, parietal lobe, posterior temporal lobe, and temporal pole extended to the amygdalo-hippocampal complex. RESULTS: Fifty-nine patients (44 men (75%), mean age 61.2 years) were included. Most patients had a severe COVID-19, 57 (97%) needed oxygen therapy and 43 (73%) were hospitalized in intensive care unit at the time of MRI. Morphological brain MRI was abnormal in 44 (75%) patients. ASL perfusion was abnormal in 53 (90%) patients, and particularly in all patients with normal morphological MRI. Hypoperfusion occurred in 48 (81%) patients, mostly in temporal poles (52 (44%)) and frontal lobes (40 (34%)). Hyperperfusion occurred in 9 (15%) patients and was closely associated with post-contrast FLAIR leptomeningeal enhancement (100% [66.4%-100%] of hyperperfusion with enhancement versus 28.6% [16.6%-43.2%] without, p = 0.002). Studied clinical parameters (especially sedation) and other morphological MRI anomalies had no significant impact on perfusion anomalies. CONCLUSION: Brain ASL perfusion showed hypoperfusion in more than 80% of patients with severe COVID-19, with or without visible lesion on conventional MRI abnormalities.

Cerebrospinal Fluid Features in Patients With Coronavirus Disease 2019 and Neurological Manifestations: Correlation with Brain Magnetic Resonance Imaging Findings in 58 Patients.

BACKGROUND: Neurological manifestations are common in patients with coronavirus disease 2019 (COVID-19), but little is known about pathophysiological mechanisms. In this single-center study, we examined neurological manifestations in 58 patients, including cerebrospinal fluid (CSF) analysis and neuroimaging findings. METHODS: The study included 58 patients with COVID-19 and neurological manifestations in whom severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) reverse-transcription polymerase chain reaction screening and on CSF analysis were performed. Clinical, laboratory, and brain magnetic resonance (MR) imaging data were retrospectively collected and analyzed. RESULTS: Patients were mostly men (66%), with a median age of 62 years. Encephalopathy was frequent (81%), followed by pyramidal dysfunction (16%), seizures (10%), and headaches (5%). CSF protein and albumin levels were increased in 38% and 23%, respectively. A total of 40% of patients displayed an elevated albumin quotient, suggesting impaired blood-brain barrier integrity. CSF-specific immunoglobulin G oligoclonal band was found in 5 patients (11%), suggesting an intrathecal synthesis of immunoglobulin G, and 26 patients (55%) presented identical oligoclonal bands in serum and CSF. Four patients (7%) had a positive CSF SARS-CoV-2 reverse-transcription polymerase chain reaction. Leptomeningeal enhancement was present on brain MR images in 20 patients (38%). CONCLUSIONS: Brain MR imaging abnormalities, especially leptomeningeal enhancement, and increased inflammatory markers in CSF are frequent in patients with neurological manifestations related to COVID-19, whereas SARS-CoV-2 detection in CSF remained scanty.

Impact of COVID-19 and lockdown regarding blood transfusion.

BACKGROUND: The outbreak of a SARS-CoV-2 resulted in a massive afflux of patients in hospital and intensive care units with many challenges. Blood transfusion was one of them regarding both blood banks (safety, collection, and stocks) and consumption (usual care and unknown specific demand of COVID-19 patients). The risk of mismatch was sufficient to plan blood transfusion restrictions if stocks became limited. STUDY DESIGN AND METHODS: Analyses of blood transfusion in a tertiary hospital and blood collection in the referring blood bank between February 24 and May 31, 2020. RESULTS: Withdrawal of elective surgery and non-urgent care and admission of 2291 COVID-19 patients reduced global activity by 33% but transfusion by 17% only. Only 237 (10.3) % of COVID-19 patients required blood transfusion, including 45 (2.0%) with acute bleeding. Lockdown and cancellation of mobile collection resulted in an 11% reduction in blood donation compared to 2019. The ratio of reduction in blood transfusion to blood donation remained positive and stocks were slightly enhanced. DISCUSSION: Reduction of admissions due to SARS-CoV-2 pandemic results only in a moderate decrease of blood transfusion. Incompressible blood transfusions concern urgent surgery, acute bleeding (including some patients with COVID-19, especially under high anticoagulation), or are supportive for chemotherapy-induced aplasia or chronic anemia. Lockdown results in a decrease of blood donation by cancellation of mobile donation but with little impact on a short period by mobilization of usual donors. No mismatch between demand and donation was evidenced and no planned restriction to blood transfusion was necessary.

Acute Pulmonary Embolism in Patients with COVID-19 at CT Angiography and Relationship to d-Dimer Levels.

Online supplemental material is available for this article.

Brain MRI Findings in Severe COVID-19: A Retrospective Observational Study.

Background Brain MRI parenchymal signal abnormalities have been associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Purpose To describe the neuroimaging findings (excluding ischemic infarcts) in patients with severe coronavirus disease 2019 (COVID-19) infection. Materials and Methods This was a retrospective study of patients evaluated from March 23, 2020, to April 27, 2020, at 16 hospitals. Inclusion criteria were (a) positive nasopharyngeal or lower respiratory tract reverse transcriptase polymerase chain reaction assays, (b) severe COVID-19 infection defined as a requirement for hospitalization and oxygen therapy, (c) neurologic manifestations, and (d) abnormal brain MRI findings. Exclusion criteria were patients with missing or noncontributory data regarding brain MRI or brain MRI showing ischemic infarcts, cerebral venous thrombosis, or chronic lesions unrelated to the current event. Categorical data were compared using the Fisher exact test. Quantitative data were compared using the Student t test or Wilcoxon test. P < .05 represented a significant difference. Results Thirty men (81%) and seven women (19%) met the inclusion criteria, with a mean age of 61 years ± 12 (standard deviation) (age range, 8-78 years). The most common neurologic manifestations were alteration of consciousness (27 of 37, 73%), abnormal wakefulness when sedation was stopped (15 of 37, 41%), confusion (12 of 37, 32%), and agitation (seven of 37, 19%). The most frequent MRI findings were signal abnormalities located in the medial temporal lobe in 16 of 37 patients (43%; 95% confidence interval [CI]: 27%, 59%), nonconfluent multifocal white matter hyperintense lesions seen with fluid-attenuated inversion recovery and diffusion-weighted sequences with variable enhancement, with associated hemorrhagic lesions in 11 of 37 patients (30%; 95% CI: 15%, 45%), and extensive and isolated white matter microhemorrhages in nine of 37 patients (24%; 95% CI: 10%, 38%). A majority of patients (20 of 37, 54%) had intracerebral hemorrhagic lesions with a more severe clinical presentation and a higher admission rate in intensive care units (20 of 20 patients [100%] vs 12 of 17 patients without hemorrhage [71%], P = .01) and development of the acute respiratory distress syndrome (20 of 20 patients [100%] vs 11 of 17 patients [65%], P = .005). Only one patient had SARS-CoV-2 RNA in the cerebrospinal fluid. Conclusion Patients with severe coronavirus disease 2019 and without ischemic infarcts had a wide range of neurologic manifestations that were associated with abnormal brain MRI scans. Eight distinctive neuroradiologic patterns were described. © RSNA, 2020.

Treatment with a platelet-activating factor receptor antagonist improves hemodynamics and reduces epinephrine requirements, in a lethal rodent model of anaphylactic shock.

BACKGROUND: In some cases, anaphylactic shock (AS) is still lethal, despite rapid use of epinephrine. High doses of epinephrine are associated with severe complications. Platelet-activating factor (PAF) is secreted in massive amounts during AS, and a high plasma level is correlated with increased AS severity. OBJECTIVE: To assess the effect of ABT-491, a PAF-receptor antagonist and possible adjunct treatment, alone or in combination with epinephrine during AS. METHODS: AS was induced by intravenous injection of 1 mg ovalbumin into ovalbumin-sensitized rats. Rats were then randomly assigned to 5 groups (n = 10 per group): SHAM (vehicle only), SHOCK (no treatment), ABT (ABT-491 1 mg/kg), EPI (epinephrine 5 µg as a bolus then 10 µg kg-1  min-1 by continuous infusion, followed by a reducing protocol) and EPI-ABT (both treatments). RESULTS: Ovalbumin injection resulted in a severe decrease in mean arterial pressure, left ventricular inotropy (max dP/dt) and left ventricular shortening fraction (LVSF). All rats from the ABT group survived until the end of the experiment. ABT-491 prevented the LVSF decrease observed in the SHOCK group (at T15: ABT 50% ± 11% vs SHOCK 36% ± 9%, P = .01), significantly reduced the dose of epinephrine needed to treat anaphylactic shock (EPI-ABT 314 ± 67 µg/kg vs EPI 475 ± 69 µg/kg, P < .001) and reduced the time to restore basal MAP (ABT 23 ± 7 minutes vs EPI-ABT 13 ± 5 minutes, P < .01). CONCLUSIONS AND CLINICAL RELEVANCE: AS was characterized by early cardiac dysfunction in our model. Treatment with ABT-491 allowed survival until the end of the experiment and reduced cardiac dysfunction. Use of the PAF-R antagonist had a synergistic effect with epinephrine and allowed a significant reduction in epinephrine consumption. Use of PAF-R antagonists during AS could reduce epinephrine-related complications and improve the treatment of epinephrine refractory cases.

Risk factors and events in the adult intensive care unit associated with pain as self-reported at the end of the intensive care unit stay.

BACKGROUND: The short-term and long-term consequences of the most frequent painful procedures performed in the ICU are unclear. This study aimed to identify the risk factors associated with pain-related discomfort perceived by critically ill patients during the whole ICU stay as self-reported by patients at the end of their ICU stay. METHODS: The study involved 34 ICUs. Adult patients who survived an ICU stay of 3 calendar days or more were eligible for inclusion. Discomforts, including the pain-related discomfort, were assessed using the French 18-item questionnaire on discomfort in ICU patients, the "Inconforts des Patients de REAnimation" (IPREA). Patients scored each item from 0 (minimal discomfort) to 10 (maximal discomfort). Associations between patient characteristics at ICU admission, life support therapies and main potentially painful procedures performed during the ICU stay and pain-related discomfort scores assessed at the end of the ICU stay were analyzed. RESULTS: Patients with complete IPREA questionnaires (n = 2130) were included. The median pain-related discomfort score was 3 (IQR 0-5). From the univariate analysis, pain-related discomfort scores were negatively correlated with age and positively correlated with ICU stay duration; surgical patients reported significant higher pain-related discomfort scores than medical patients; chest drain insertion, chest drain removal, use of bladder catheter, central venous catheter (CVC) insertion, complex dressing change, and intra-hospital transport were associated with pain-related discomfort scores. From the multivariate analyses using generalized estimating equations models, only age, chest drain removal, use of a bladder catheter, CVC insertion, and intra-hospital transport were the main risk factors associated with pain-related discomfort scores. CONCLUSION: Patients who underwent chest drain removal, bladder catheter, CVC insertion, and intra-hospital transport during their ICU stay reported higher pain-related discomfort scores (with respect to the whole ICU stay and assessed at the end of their ICU stay) than patients who did not experience these events. This study may pave the way for further targeted studies aiming at investigating a causal link between these common procedures in the ICU and adult critically ill patients' perceptions of their ICU stay regarding recalled pain. TRIAL REGISTRATION: Clinicaltrials.gov Identifier NCT02442934, retrospectively registered on May 13, 2015.

Assessment of patients' self-perceived intensive care unit discomforts: Validation of the 18-item version of the IPREA.

BACKGROUND AND AIMS: We reported the validation of the 18-item version of the 'Inconforts des Patients de REAnimation (IPREA)' questionnaire that includes 2 new items exploring feeling depressed and shortness of breath during an intensive care unit (ICU) stay. METHODS: The validation process was integrated in a multicenter, cluster-randomized, controlled, two-parallel group study built to assess the effectiveness of a tailored multicomponent program for reducing self-perceived discomfort in the ICU. All patients aged 18 years or older who survived an ICU stay of 3 calendar days or more were eligible for inclusion. Data collection included demographics (sex, age), type of admission (medical and surgical), health status scores at admission (Knaus score and McCabe index, Simplified Acute Physiology Score (SAPS) II), specific ICU therapeutics such as mechanical ventilation (MV), noninvasive ventilation (NIV), use of vasopressors, or renal replacement therapy (RRT), and ICU stay duration. RESULTS: A total of 994 patients were included. The initial structure of IPREA was confirmed using confirmatory factor analysis showing satisfactory fit (RMSEA at 0.042, CFI at 0.912). No multidimensional structure was identified, allowing the calculation of an overall discomfort score. The three highest discomforts were sleep deprivation, thirst, and perfusion lines and other devices, and the 3 lowest discomforts were limited visiting hours, hunger, and isolation. The overall discomfort score of the 18-item version of IPREA did not differ between men and women. Higher age was significantly correlated with a lower overall discomfort score. While MV was not linked to self-reported discomfort, patients treated by NIV reported higher overall discomfort scores than patients not treated by NIV. CONCLUSION: The 18-item version of IPREA is easy to use and possesses satisfactory psychometric properties. The availability of a reliable and valid French questionnaire asking about patients' self-perceived ICU discomforts enables feedback from the health care team to be incorporated in a continuous quality health care improvement strategy. TRIAL REGISTRATION: clinicaltrial.gov NCT02442934 (registration date: May 18, 2015, retrospectively registered).

Adjusted calculation model of heparin management during cardiopulmonary bypass in obese patients: A randomised controlled trial.

BACKGROUND: Anticoagulation during cardiopulmonary bypass (CPB) is usually adapted to total body weight (TBW). This may be inaccurate in obese patients and lead to heparin overdose with a risk of bleeding. OBJECTIVES: To validate the efficacy and safety of an adjusted calculation model of heparin dosing based on ideal body weight (IBW) rather than TBW in obese CPB patients, with an expected target mean plasma heparin concentration of 4.5 IU ml after onset of CPB in the experimental group. DESIGN: Randomised controlled study. SETTING: University hospital. PATIENTS: Sixty obese patients (BMI ≥ 30 kg m) scheduled for CPB were included from January to June 2016. INTERVENTIONS: Patients received a bolus dose of unfractionated heparin of either 300 IU kg of TBW or 340 IU kg of IBW before onset of CPB. Additional adjusted boluses were injected to maintain an activated clotting time (ACT) of at least 400 s. MAIN OUTCOME MEASURES: Plasma heparin concentration and ACT were measured at different time points. Total heparin doses and transfusion requirements were recorded. RESULTS: The target heparin concentration of 4.5 IU ml was reached in the IBW group at the onset of CPB and maintained at all time points during CPB. Heparin concentrations were significantly higher in the TBW group after the bolus (6.52 ±â€Š0.97 vs. 4.54 ±â€Š1.13 IU ml, P < 0.001) and after cardioplegia (5.10 ±â€Š1.03 vs. 4.31 ±â€Š1.00 IU ml, P = 0.02). Total heparin doses were significantly higher in the TBW group. Mean ACT was significantly lower in the IBW group but remained over 400 s during CPB. The correlation between heparin and ACT was poor. Peri-operative bleeding and transfusion requirements were comparable. No thrombotic event occurred in the CPB circuit. CONCLUSION: The current IBW-adjusted regimen of heparin administration may be used efficiently in obese CPB patients, thereby avoiding overdose which cannot be accurately assessed by ACT monitoring alone. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02675647.

Epinephrine but not vasopressin attenuates the airway response to anaphylactic shock in rats.

PURPOSE: The two life-threatening signs of anaphylactic shock (AS) are severe arterial hypotension and bronchospasm. Guidelines recommend epinephrine as first-line treatment. Arginine vasopressin (AVP) has been proposed as an alternative if epinephrine does not correct arterial hypotension. These two drugs may have beneficial, neutral or deleterious effects on airflow either directly or by modifying factors that regulate vasodilatation and/or edema in the bronchial wall. AIM OF THE STUDY: To compare the effects of epinephrine and AVP on airflow and airway leakage in a rat model of AS. MATERIALS AND METHODS: Thirty-two ovalbumin-sensitized rats were randomized into four groups: control (CON), AS without treatment (OVA), AS treated with epinephrine (EPI), and AS treated with AVP (AVP). Mean arterial pressure (MAP), respiratory resistance and elastance and microvascular leakage in the airways were measured. RESULTS: All OVA rats died within 20 minutes following ovalbumin injection. Ovalbumin induced severe arterial hypotension and airway obstruction (221 ± 36 hPa.s.L-1 vs. vehicle 52 ± 8 hPa.s.L-1; p < 0.0001) associated with microvascular leakage distributed throughout the trachea, bronchi and intra-pulmonary airways. EPI and AVP extended survival time; EPI restored a higher level of MAP than AVP. Airway obstruction was attenuated by epinephrine (146 ± 19 hPa.s.L-1; p < 0.0001), but not by AVP (235 ± 58 hPa.s.L-1; p = 0.42). CONCLUSIONS: Epinephrine was superior to AVP for alleviating the airway response in a rat model of AS. When bronchospasm and severe arterial hypotension are present during AS, epinephrine should be the drug of choice.

Identifying optimal heparin management during cardiopulmonary bypass in obese patients: A prospective observational comparative study.

BACKGROUND: The heparin regimen providing anticoagulation during cardiopulmonary bypass (CPB) is usually adapted to total body weight (TBW), but may be inaccurate in obese patients in whom TBW exceeds their ideal body weight. OBJECTIVES: The objective is to compare the effects of heparin injection based on TBW on haemostatic parameters between obese and nonobese patients during cardiac surgery and to calculate the optimal heparin regimen. DESIGN: Prospective comparative study. SETTING: University hospital. PATIENTS: Two groups of 50 patients (BMI≥ or <30 kg m) were included in the study over a 9-month period in 2013. The study started on 27 February 2013. INTERVENTIONS: An unfractionated heparin (UFH) bolus of 300 IU kg TBW was injected before initiation of CPB followed by additional doses (50 to 100 IU kg) to maintain a target activated coagulation time (ACT) of at least 400 s. MAIN OUTCOME MEASURES: ACT and plasma heparin concentration were measured at different time points after initiation of, and weaning from CPB. RESULTS: Obese patients received higher initial and total doses of heparin (P < 0.0001). Plasma heparin concentrations were significantly higher in obese patients at each time point (P < 0.001) and reached very high values after the initial bolus (5.90 vs. 4.48 IU ml, P < 0.0001). The relationship between plasma heparin concentration and ACT after the initial bolus was not linear and followed an asymptotic regression curve. Haemoglobin concentration decreased intraoperatively to a greater extent in the obese group (P < 0.001). No significant differences in postoperative bleeding or global transfusion requirements were observed. CONCLUSION: The standard heparin regimen based on TBW in obese patients during CPB results in excessive plasma heparin concentrations and a significant intraoperative decrease in haemoglobin concentration. ACT monitoring was not accurate in identifying this excess dosage. An initial bolus of 340 IU kg ideal body weight would achieve a heparin concentration of 4.5 IU ml, similar to that observed in nonobese patients. Further investigations are warranted to confirm this heparin regimen.

Epinephrine, compared with arginine vasopressin, is associated with similar haemodynamic effects but significantly improved brain oxygenation in the early phase of anaphylactic shock in rats: An experimental study.

BACKGROUND: In contrast to other types of shock, anaphylactic shock decreases cerebral blood flow more than would be expected from severe arterial hypotension, thus potentially affecting survival through brain ischaemia/hypoxia. We hypothesised that epinephrine (EPI) used as a first-line treatment of anaphylactic shock and arginine vasopressin (AVP) proposed in case of EPI refractoriness may have different effects on brain oxygenation. OBJECTIVES: To compare the effect of EPI and AVP on brain oxygenation under similar macro-haemodynamic target values in an anaphylactic shock model. DESIGN: Prospective laboratory study. SETTING: University laboratory. ANIMALS: Male brown Norway rats (n = 27). INTERVENTIONS: Twenty-seven rats were sensitised with ovalbumin (OVA). Twenty rats had anaphylactic shock induced with OVA and were resuscitated with either 0.9% saline (OVA group), EPI (EPI group) or AVP (AVP group). Sensitised control rats received only 0.9% saline and no OVA (CON group). MAIN OUTCOME MEASURES: Mean arterial pressure (MAP), carotid artery blood flow (CaBF), cerebral cortical blood flow (CBF) and hippocampal oxygen partial pressure (PtiO2) were recorded. RESULTS: All rats in the OVA group died within 15 min. EPI and AVP restored comparable levels of MAP, carotid artery blood flow and CBF, and extended survival time. EPI was associated with biologically relevant and significantly (P < 0.05) higher PtiO2 values (nadir values at 20 min: 25.0 ± 2.2 mmHg) compared with the AVP group (14.9 ± 2.0 mmHg). The slopes of the correlations of MAP vs. PtiO2 and CBF were significantly steeper with AVP (more pressure dependence) compared with EPI. By the end of the experiment, hippocampal PtiO2 values between the EPI (24.1 ± 2.1 mmHg) and the AVP (20.8 ± 2.0 mmHg) groups were similar. CONCLUSION: At early, but not at late time points, resuscitation of anaphylactic shock with EPI or AVP to similar MAP and CBF endpoints resulted in hippocampal PtiO2 being significantly higher after EPI. In addition, the PtiO2 after EPI always remained above the threshold for brain hypoxia, whereas PtiO2 after AVP was below the hypoxic threshold most of the time. Because of this early brain hypoxia, AVP may not be the drug of first choice for resuscitation of anaphylactic shock.

Post-intubation tracheal rupture: poor healing of the tracheal wall.

PURPOSE: To describe tracheal rupture after orotracheal intubation assisted by a tracheal tube introducer. CLINICAL FEATURES: A 73-yr-old morbidly obese female patient with a history of hypertension underwent a total knee replacement. There were no anticipated signs of difficult intubation. Orotracheal intubation was attempted twice by direct laryngoscopy, and a Boussignac bougie was used as a tube exchanger for the second attempt. Seven hours after tracheal extubation, the patient became dyspneic and showed a large subcutaneous emphysema. A chest x-ray and computerized tomography scan revealed rupture of the posterior tracheal wall. The distal part of the injury was 26.5 cm from the patient's teeth and 0.5 cm from the carina (i.e., beyond the normal location of the tracheal tube tip) and extended to the origin of the right main bronchus, where the tip of the Boussignac bougie was probably pushed. Formation of an endotracheal sac occurred during the first two weeks after intubation, accompanied by dyspnea and alveolar hypoventilation, but symptoms resolved favourably with conservative management. CONCLUSION: The tracheal rupture was attributed to airway manipulations, and the distal location of the lesion suggests that the cause was the Boussignac bougie rather than the tracheal tube. Long-term healing of the injury was satisfactory, although the patient continued to complain of dyspnea one year after the rupture.

Early chest tube removal on the 1st postoperative day protocol of an enhanced recovery after cardiac surgery programme is safe.

OBJECTIVES: The aim of this study was to assess the safety of early chest tube removal (CTR) protocol on the 1st postoperative day (POD1) of our Enhanced Recovery After Surgery (ERAS) programme by comparing the risk of postoperative pneumothorax, pleural and pericardial effusion requiring intervention and hospital mortality. METHODS: All consecutive patients undergoing elective coronary revascularization and/or valve surgery between 2015 and 2021 were assessed in terms of their perioperative management pathways: conventional standard of care (control group) versus standardized systematic perioperative ERAS programme including an early CTR on POD1 (ERAS group). A propensity score matching was applied. The primary end-point was a composite of postoperative pneumothorax, pleural and pericardial effusion requiring intervention and hospital mortality. RESULTS: A total of 3153 patients were included. Propensity score analysis resulted in 2 groups well-matched pairs of 1026 patients. CTR on POD1 was significantly increased from 29.5% in the control group to 70.3% in the ERAS group (P < 0.001). The incidence of the primary end-point was 6.4% in the control group and 6.9% in the ERAS group (P = 0.658). Patients in the ERAS group, as compared with control group, had significant lower incidence of bronchopneumonia (9.0% vs 13.5%; P = 0.001) and higher incidence of mechanical ventilation ≤6 h (84.6% vs 65.2%; P < 0.001), length of intensive care unit ≤1 day (61.2% vs 50.8%; P < 0.001) and hospital ≤6 days (67.3% vs.43.2%; P < 0.001). CONCLUSIONS: CTR on POD1 protocol can be safely incorporated into a standardized systematic ERAS programme, enabling early mobilization, and contributing to the improvement of postoperative outcomes. CLINICAL TRIAL REGISTRATION NUMBER: Ethics committee of the French Society of Thoracic and Cardio-Vascular Surgery (CERC-SFCTCV-2022-09-13_23140).

Infectious Mediastinitis: A Retrospective Cohort Study.

Background: This study aimed to characterize the demographics, microbiology, management and treatment outcomes of mediastinitis according to the origin of the infection. Methods: This retrospective observational study enrolled patients who had mediastinitis diagnosed according to the criteria defined by the Centers for Disease Control and Prevention and were treated in Strasbourg University Hospital, France, between 1 January 2010 and 31 December 2020. Results: We investigated 151 cases, including 63 cases of poststernotomy mediastinitis (PSM), 60 cases of mediastinitis due to esophageal perforation (MEP) and 17 cases of descending necrotizing mediastinitis (DNM). The mean patient age (standard deviation) was 63 (14.5) years, and 109 of 151 patients were male. Microbiological documentation varied according to the origin of the infection. When documented, PSM cases were mostly monomicrobial (36 of 53 cases [67.9%]) and involved staphylococci (36 of 53 [67.9%]), whereas MEP and DNM cases were mostly plurimicrobial (38 of 48 [79.2%] and 8 of 12 [66.7%], respectively) and involved digestive or oral flora microorganisms, respectively. The median duration of anti-infective treatment was 41 days (interquartile range, 21-56 days), and 122 of 151 patients (80.8%) benefited from early surgical management. The overall 1-year survival rate was estimated to be 64.8% (95% confidence interval, 56.6%-74.3%), but varied from 80.1% for DNM to 61.5% for MEP. Conclusions: Mediastinitis represents a rare yet deadly infection. The present cohort study exhibited the different patterns observed according to the origin of the infection. Greater insight and knowledge on these differences may help guide the management of these complex infections, especially with respect to empirical anti-infective treatments.

Methylene blue and epinephrine: a synergetic association for anaphylactic shock treatment.

BACKGROUND: Severe hypotension resulting from anaphylactic shock may be refractory to epinephrine and impair cerebral oxygenation and metabolism contributing to anaphylactic shock morbidity and mortality. Refractoriness to epinephrine could be corrected by nitric oxide pathway inhibitors such as methylene blue. OBJECTIVES: To compare the systemic and regional (brain and skeletal muscle) effects of epinephrine and methylene blue given alone or in combination in a rat model of anaphylactic shock. DESIGN: Prospective laboratory study. SETTING: University laboratory. SUBJECTS: Male Brown-Norway rats (n = 60). INTERVENTIONS: After sensitization and induction of anaphylactic shock by ovalbumin, animals received either vehicle (ovalbumin group) or a 3-mg/kg methylene blue bolus (methylene blue group) or epinephrine (epinephrine group) or both (methylene blue-epinephrine group). Sensitized control rats received only vehicle and no ovalbumin (control group). MEASUREMENT AND MAIN RESULTS: Mean arterial pressure, cardiac output, cerebral blood flow, skeletal muscular oxygen partial pressure, cerebral oxygen partial pressure, skeletal muscular, and cerebral interstitial lactate/pyruvate ratio were measured. Cleaved caspase 3 and hypoxia-inducible factor-1α expression were analyzed in the cerebral cortex by Western blot. Without treatment, rats died rapidly within 15 mins from a decrease in cardiac output and mean arterial pressure, whereas treated rats survived until the end of the experiment. Methylene blue alone extended survival time but without significant improvement of hemodynamic variables and tissue perfusion and did not prevent neuronal injury. Epinephrine restored partially systemic hemodynamic variables and cerebral perfusion preventing glutamate-induced excitotoxicity. Compared with epinephrine alone, the methylene blue-epinephrine association avoided neuronal excitotoxicity and had an additive effect both on hemodynamic variables and for prevention of brain ischemia. Neither treatment could significantly restore cardiac output or prevent muscular compartment ischemia and microvascular leakage. CONCLUSIONS: Anaphylactic shock is associated with severe impairment of cerebral blood flow despite correction of arterial hypotension. Epinephrine must still be considered as the first-line vasoconstrictive agent to treat anaphylactic shock. The epinephrine-methylene blue association was the most effective treatment to prevent cerebral ischemia and could be used in anaphylactic shock refractory to epinephrine.