Probabilistic Prediction of Gastrointestinal Ischemia after Cardiothoracic Surgery.

BACKGROUND: Gastrointestinal ischemia (GIisch) is challenging to diagnose in patients after cardiothoracic surgery. Computed tomography angiography (CTA) carries substantial false-negative and false-positive rates. The aim of the study was to evaluate if a combination of readily available variables improves the diagnosis of GIisch after cardiothoracic surgery. METHODS: This retrospective study included patients receiving intensive care after cardiothoracic surgery. GIisch was confirmed by surgical and/or endoscopic findings. A GIisch prediction score was developed using the Spiegelhalter-Knill-Jones system in a training cohort then tested in a validation cohort (patients without obvious signs of GIisch on CTA). RESULTS: The training cohort comprised 125 consecutive patients with suspected GIisch in 2008 to 2019, including 85 with confirmed GIisch. CTA, performed in 92 patients, had a high false-negative rate of 17/60 (28%) and a lower false-positive rate of 7/32 (22%). The score included cardiopulmonary bypass, negatively associated with GIisch, and six variables positively associated with GIisch: intraoperative mean arterial pressure < 50 mm Hg, aspartate aminotransferase > 15 N, lactate increase in 24 hour > 20%, and 3 CTA findings, namely, bowel dilation, bowel wall thickening, and mesenteric vasoconstriction. The area under the receiver operating characteristic was 0.82 (95% confidence interval [CI], 0.51-0.93) in the training cohort and 0.82 (95% CI, 0.68-0.96) in the validation cohort (n = 34 patients). Reliability of the predicted probabilities was greatest for probabilities ≤ 30% or ≥ 70%. CONCLUSION: In patients receiving intensive care after cardiothoracic surgery, GIisch cannot be ruled out based solely on CTA findings. A scoring system combining CTA findings with other variables may improve the diagnosis of GIisch in this population.

Circuit change during extracorporeal membrane oxygenation: single-center retrospective study of 48 changes.

BACKGROUND: Bleeding and thrombosis induce major morbidity and mortality in patients under extracorporeal membrane oxygenator (ECMO). Circuit changes can be performed for oxygenation membrane thrombosis but are not recommended for bleeding under ECMO. The objective of this study was to evaluate the course of clinical, laboratory, and transfusion parameters before and after ECMO circuit changes warranted by bleeding or thrombosis. METHODS: In this single-center, retrospective, cohort study, clinical parameters (bleeding syndrome, hemostatic procedures, oxygenation parameters, transfusion) and laboratory parameters (platelet count, hemoglobin, fibrinogen, PaO2) were collected over the seven days surrounding the circuit change. RESULTS: In the 274 patients on ECMO from January 2017 to August 2020, 48 circuit changes were performed in 44 patients, including 32 for bleeding and 16 for thrombosis. Mortality was similar in the patients with vs. without changes (21/44, 48% vs. 100/230, 43%) and in those with bleeding vs. thrombosis (12/28, 43% vs. 9/16, 56%, P = 0.39). In patients with bleeding, numbers of bleeding events, hemostatic procedures, and red blood cell transfusions were significantly higher before vs. after the change (P < 0.001); the platelet counts and fibrinogen levels decreased progressively before and increased significantly after the change. In patients with thrombosis, numbers of bleeding events and red blood cell transfusions did not change after membrane change. No significant differences were demonstrated between oxygenation parameters (ventilator FiO2, ECMO FiO2, and PaO2) and ECMO flow before vs. after the change. CONCLUSIONS: In patients with severe and persistent bleeding, changing the ECMO circuit decreased clinical bleeding and red blood cell transfusion needs and increased platelets and fibrinogen levels. Oxygenation parameters did not change significantly in the group with thrombosis.

Real-World Experience with a Human Fibrinogen Concentrate: Clinical Data from Adult and Pediatric Patients Requiring Fibrinogen for Bleeding Control and Prevention.

Human fibrinogen concentrate (Fibryga) received temporary approval for fibrinogen replacement therapy in France (2017), with subsequent full approval for congenital and acquired hypofibrinogenemia. We evaluated real-world use for on-demand treatment of bleeding and prophylaxis to enhance our knowledge on fibrinogen concentrate as an option for fibrinogen replacement. Data were retrospectively collected from adult and pediatric patients with fibrinogen deficiency. The primary end point was indication for fibrinogen concentrate use; the secondary end point was treatment success for on-demand treatment/perioperative prophylaxis. The study included 150 adult (median age, 62 years; range, 18-94 years) and 50 pediatric (median age, 3 years; range, 0.01-17 years) patients with acquired fibrinogen deficiency. Fibrinogen concentrate was administered to 47.3% for nonsurgical bleeding, 22.7% for surgical bleeding, and 30.0% for perioperative prophylaxis in adult patients, and to 4.0% for surgical bleeding and 96.0% for perioperative prophylaxis in pediatric patients. Cardiac surgeries accounted for 79.5%/75.0% perioperative prophylaxis and 82.4%/100.0% surgical bleeding cases in adult/pediatric patients, respectively. The mean ± standard deviation (SD, median) total fibrinogen doses were 3.06 ± 1.69 g (32.61 mg/kg), 2.09 ± 1.36 g (22.99 mg/kg), and 2.36 ± 1.25 g (29.67 mg/kg) for adult nonsurgical bleeding, surgical bleeding, and perioperative prophylaxis, respectively; doses of 0.75 ± 0.35 g (47.64 mg/kg) and 0.83 ± 0.62 g (55.56 mg/kg) were used for pediatric surgical bleeding and perioperative prophylaxis, respectively. Treatment success was 85.7%/97.1/93.3% in adults and 50.0%/87.5% in pediatrics for nonsurgical bleeding (adults only), surgical bleeding, and perioperative prophylaxis, respectively. Fibrinogen concentrate demonstrated favorable effectiveness and safety across the age groups. This study contributes to evidence supporting fibrinogen concentrate for bleeding control/prevention in real-world clinical practice, particularly for patients with acquired fibrinogen deficiency.

Effect of non-invasive ventilation after extubation in critically ill patients with obesity in France: a multicentre, unblinded, pragmatic randomised clinical trial.

BACKGROUND: Non-invasive ventilation (NIV) and oxygen therapy (high-flow nasal oxygen [HFNO] or standard oxygen) following extubation have never been compared in critically ill patients with obesity. We aimed to compare NIV (alternating with HFNO or standard oxygen) and oxygen therapy (HFNO or standard oxygen) following extubation of critically ill patients with obesity. METHODS: In this multicentre, parallel group, pragmatic randomised controlled trial, conducted in 39 intensive care units in France, critically ill patients with obesity undergoing extubation were randomly assigned (1:1) to either the NIV group or the oxygen therapy group. Two randomisations were performed: first, randomisation to either NIV or oxygen therapy, and second, randomisation to either HFNO or standard oxygen (also 1:1), which was nested within the first randomisation. Blinding of the randomisation was not possible, but the statistician was masked to group assignment. The primary outcome was treatment failure within 3 days after extubation, a composite of reintubation for mechanical ventilation, switch to the other study treatment, or premature discontinuation of study treatment. The primary outcome was analysed by intention to treat. Effect of medical and surgical status was assessed. The reintubation within 3 days was analysed by intention to treat and after a post-hoc crossover analysis. This study is registered with ClinicalTrials.gov, number NCT04014920. FINDINGS: From Oct 2, 2019, to July 17, 2021, of the 1650 screened patients, 981 were enrolled. Treatment failure occurred in 66 (13·5%) of 490 patients in the NIV group and in 130 (26·5%) of 491 patients in the oxygen-therapy group (relative risk 0·43; 95% CI 0·31-0·60, p<0·0001). Medical or surgical status did not modify the effect of NIV group on the treatment-failure rate. Reintubation within 3 days after extubation was similar in the non-invasive ventilation group and in the oxygen therapy group in the intention-to-treat analysis (48 (10%) of 490 patients and 59 (12%) of 491 patients, p=0·26) and lower in the NIV group than in the oxygen-therapy group in the post-hoc cross-over (51 (9%) of 560 patients and 56 (13%) of 421 patients, p=0·037) analysis. No severe adverse events were reported. INTERPRETATION: Among critically ill adults with obesity undergoing extubation, the use of NIV was effective to reduce treatment-failure within 3 days. Our results are relevant to clinical practice, supporting the use of NIV after extubation of critically ill patients with obesity. However, most of the difference in the primary outcome was due to patients in the oxygen therapy group switching to NIV, and more evidence is needed to conclude that an NIV strategy leads to improved patient-centred outcomes. FUNDING: French Ministry of Health.

Impact of Prone Position in COVID-19 Patients on Extracorporeal Membrane Oxygenation.

OBJECTIVES: Prone positioning and venovenous extracorporeal membrane oxygenation (ECMO) are both useful interventions in acute respiratory distress syndrome (ARDS). Combining the two therapies is feasible and safe, but the effectiveness is not known. Our objective was to evaluate the potential survival benefit of prone positioning in venovenous ECMO patients cannulated for COVID-19-related ARDS. DESIGN: Retrospective analysis of a multicenter cohort. PATIENTS: Patients on venovenous ECMO who tested positive for severe acute respiratory syndrome coronavirus 2 by reverse transcriptase polymerase chain reaction or with a diagnosis on chest CT were eligible. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: All patients on venovenous ECMO for respiratory failure in whom prone position status while on ECMO and in-hospital mortality were known were included. Of 647 patients in 41 centers, 517 were included. Median age was 55 (47-61), 78% were male and 95% were proned before cannulation. After cannulation, 364 patients (70%) were proned and 153 (30%) remained in the supine position for the whole ECMO run. There were 194 (53%) and 92 (60%) deaths in the prone and the supine groups, respectively. Prone position on ECMO was independently associated with lower in-hospital mortality (odds ratio = 0.49 [0.29-0.84]; p = 0.010). In 153 propensity score-matched pairs, mortality rate was 49.7% in the prone position group versus 60.1% in the supine position group (p = 0.085). Considering only patients alive at decannulation, propensity-matched proned patients had a significantly lower mortality rate (22.4% vs 37.8%; p = 0.029) than nonproned patients. CONCLUSIONS: Prone position may be beneficial in patients supported by venovenous ECMO for COVID-19-related ARDS but more data are needed to draw definitive conclusions.

Including Organ Dysfunctions in a Predictive Score for Nosocomial Pneumonia After Cardiothoracic Surgery.

BACKGROUND: Clinical diagnosis of ICU-acquired pneumonia after cardiothoracic surgery is challenging. Johanson criteria (chest radiograph infiltrate, purulent tracheal secretions, fever, and leukocytosis) fail in half the cases. A high Clinical Pulmonary Infection Score (CPIS) and ≥ 2-point increase in Sequential Organ Failure Assessment (SOFA) score (SOFA↑ ≥ 2) may improve diagnosis. The aim of the study was to evaluate whether CPIS or SOFA↑ ≥ 2 contributes to predict ICU-acquired pneumonia in subjects after cardiothoracic surgery. METHODS: We used a prospective observational design. Spiegelhalter-Knill-Jones scoring systems including CPIS or SOFA↑ ≥ 2, together with other clinical and laboratory variables, were developed in a derivation cohort. A positive quantitative pulmonary sample culture was required to confirm ICU-acquired pneumonia. Area under the receiver operating characteristic curve (AUROC) was computed for each of the 2 scoring systems. The best system was evaluated in a validation cohort. RESULTS: Derivation and validation cohorts included 172 and 108 subjects, with 410 and 216 suspected ICU-acquired pneumonia episodes, respectively. AUROC was 0.53 ± 0.03 for CPIS (P = .29) and 0.54 ± 0.03 for SOFA↑ ≥ 2 (P = .29). Adding purulent tracheal secretions and leukocytosis to SOFA↑ ≥ 2 (SOFA model) increased AUROC to 0.65 ± 0.03 (P < .001). Adding catecholamine use to CPIS (CPIS model) increased AUROC only slightly, to 0.57 ± 0.03. The probabilities predicted by the SOFA model were reliable, especially when high or low. CONCLUSIONS: A clinical scoring system including at least SOFA↑ ≥ 2 increase barely improved ICU-acquired pneumonia prediction in subjects after cardiothoracic surgery.

Oxygenation versus driving pressure for determining the best positive end-expiratory pressure in acute respiratory distress syndrome.

OBJECTIVE: The aim of this prospective longitudinal study was to compare driving pressure and absolute PaO2/FiO2 ratio in determining the best positive end-expiratory pressure (PEEP) level. PATIENTS AND METHODS: In 122 patients with acute respiratory distress syndrome, PEEP was increased until plateau pressure reached 30 cmH2O at constant tidal volume, then decreased at 15-min intervals, to 15, 10, and 5 cmH2O. The best PEEP by PaO2/FiO2 ratio (PEEPO2) was defined as the highest PaO2/FiO2 ratio obtained, and the best PEEP by driving pressure (PEEPDP) as the lowest driving pressure. The difference between the best PEEP levels was compared to a non-inferiority margin of 1.5 cmH2O. MAIN RESULTS: The best mean PEEPO2 value was 11.9 ± 4.7 cmH2O compared to 10.6 ± 4.1 cmH2O for the best PEEPDP: mean difference = 1.3 cmH2O (95% confidence interval [95% CI], 0.4-2.3; one-tailed P value, 0.36). Only 46 PEEP levels were the same with the two methods (37.7%; 95% CI 29.6-46.5). PEEP level was ≥ 15 cmH2O in 61 (50%) patients with PEEPO2 and 39 (32%) patients with PEEPDP (P = 0.001). CONCLUSION: Depending on the method chosen, the best PEEP level varies. The best PEEPDP level is lower than the best PEEPO2 level. Computing driving pressure is simple, faster and less invasive than measuring PaO2. However, our results do not demonstrate that one method deserves preference over the other in terms of patient outcome. CLINICAL TRIAL NUMBER: #ACTRN12618000554268 . Registered 13 April 2018.

Pulmonary thromboendarterectomy: The Marie Lannelongue Hospital experience.

Background: Targeted medical therapy and balloon pulmonary angioplasty (BPA) entered the field of chronic thromboembolic pulmonary hypertension (CTEPH) treatment in the early 2010's. Multimodal therapy is emerging as the new gold standard for CTEPH management. Whether this change of paradigm impacted early outcomes of pulmonary endarterectomy (PEA) remains unknown. Our aim is to report our surgical experience in the era of CTEPH multimodal management. Methods: Patients who underwent PEA between 2016 and 2020 were included in the study. Early outcomes were described and compared between three groups of patients: PEA alone, PEA after targeted medical therapy induction and PEA after BPA. Results: A total of 418 patients, 225 males and 193 females, with a mean age of 59±14 years were included in the study. 336 patients underwent PEA alone, 69 after medical targeted therapy induction and 13 after unilateral BPA. Baseline preoperative pulmonary vascular resistance [4.99 (IQR, 1.71-8.48), 6.21 (IQR, 4.37-8.1), 5.03 (IQR, 4.44-7.19) wood units (WU), P=0.230, respectively] and PEA effectiveness [% decrease mean pulmonary artery pressure (mPAP), 24 (IQR, 7-42), 25 (IQR, 7-35), 23 (IQR, 3-29), P=0.580] did not differ between groups. Compared to PEA alone and PEA+BPA, the medical therapy induction group represented the most challenging group with higher baseline mPAP (45±10 vs. 42±11 and 43±11 mmHg, P=0.047), longer circulatory arrest time (30.1±15 vs. 26.6±10 and 19.6±6 min, P=0.005), higher post-PEA extracorporeal membrane oxygenation use (20.6% vs. 8.7 and 9.1%, P=0.004), higher duration on mechanical ventilation [4 (IQR, 1-12) vs. 1 (IQR, 0.5-5) and 2 (IQR, 1-3) days, P=0.005], higher complication rate (85.5% vs. 74.6% and 76.9%, P=0.052) and higher 90-day mortality (13% vs. 3.9% and 0%, P=0.002). Compared to PEA and PEA+ medical therapy induction groups, patients in the BPA induction group were older [72 (IQR, 62-76) vs. 60 (IQR, 48-69) and 62 (IQR, 52-72) years, P=0.005], and underwent shorter cardiopulmonary bypass (191.9±47.9 vs. 222±107.2 and 236.8±46.4 min, P<0.001), aortic cross clamping (54.8±21 vs. 82.7±31.4 and 80.1±32.9 min, P=0.002) and circulatory arrest time (19.6±6.2 vs. 26.6±10.8 and 30.1±15.1 min, P=0.008). Conclusions: Multimodal therapy approach to CTEPH patients did not affect effectiveness of PEA. Medical therapy and BPA could act in synergy with surgery to treat more challenging patients.

Extubation Failure Prediction by Echography of the Diaphragm After Cardiothoracic Surgery: The EXPEDIA Study.

BACKGROUND: Successful extubation is difficult to predict. Ultrasound measurement of the diaphragm thickening fraction (DTF) might help predict weaning failure after cardiothoracic surgery. METHODS: We assessed the predictive performance of diaphragm ultrasound in a derivation cohort of 50 prospectively included cardiothoracic surgery subjects ready for a weaning trial and in a validation cohort of 39 subjects ventilated for ≥ 48 h. DTF was assessed by ultrasound during pressure support ventilation (PSV) then during a T-piece spontaneous breathing trial (SBT). DTF was the percentage change in diaphragm thickness between expiration and inspiration and DTFmax, the higher DTF value of the 2 hemidiaphragms. DTFmax during SBT (static study) and the difference in DTFmax between PSV and SBT (dynamic study) were analyzed. RESULTS: In the derivation cohort, DTFmax during SBT was 25.6 ± 17.3% in subjects with successful extubation and 65.2 ± 17.3% in those with weaning failure (difference 39.7 [95% CI 27.4-51.9], P < .01). During SBT, DTFmax ≥ 50% was associated with weaning failure (area under the receiver operating characteristic curve [AUC] 0.94 ± 0.05). In the dynamic study, a ≥ 40% DTFmax increase was associated with weaning failure (AUC 0.91 ± 0.06). In the validation cohort, DTFmax during SBT was 20.3 ± 17.1% in subjects with successful extubation and 82.0 ± 51.6% in those with weaning failure (difference 61.8 [95% CI 41.6-82.0], P < .01). During SBT, DTFmax ≥ 50% predicted weaning failure (AUC 0.99 ± 0.02). In the dynamic study, a ≥ 40% increase in DTFmax predicted weaning failure (AUC 0.81 ± 0.09). CONCLUSIONS: Measuring DTFmax during SBT and the DTFmax change when switching from PSV to SBT may help predict weaning failure after cardiothoracic surgery. The study was registered on ANZCTR. CLINICAL TRIAL REGISTRATION NUMBER: U1111-1180-1999.

Effect of Recruitment Maneuvers and PEEP on Respiratory Failure After Cardiothoracic Surgery in Obese Subjects: A Randomized Controlled Trial.

BACKGROUND: Obesity may increase the risk of respiratory failure after cardiothoracic surgery. A recruitment maneuver followed by PEEP might decrease the risk of respiratory failure in obese subjects. We hypothesized that the routine use after heart surgery of a recruitment maneuver followed by high or low PEEP level would decrease the frequency of respiratory failure in obese subjects. METHODS: In a pragmatic, randomized controlled trial, we assigned obese subjects (ie, with body mass index [BMI] ≥ 30 kg/m2) in the immediate postoperative period of cardiothoracic surgery to either volume control ventilation with 5 cm H2O of PEEP (control group) or a recruitment maneuver followed by 5 or 10 cm H2O of PEEP in the intervention arms (RM5 and RM10 groups, respectively). The primary outcome was the proportion of subjects with postextubation respiratory failure, defined as the need for re-intubation, bi-level positive airway pressure, or high-flow nasal cannula within the first 48 h. RESULTS: The study included 192 subjects: 65 in the control group (BMI 33.5 ± 3.2 kg/m2), 66 in the RM5 group (BMI 34.5 ± 3.2 kg/m2, and 61 in RM10 group (BMI 33.8 ± 4.8 kg/m2). Postextubation respiratory failure occurred in 14 subjects in the control group (21.5% [95% CI 13.3-35.3]), 21 subjects in the RM5 group (31.8% [95% CI 21.2-44.6]), and 9 subjects in the RM10 group (14.7% [95% CI 7.4-26.7]) (P = .07). The recruitment maneuver was stopped prematurely due to severe hypotension in 8 (12.1%) RM5 subjects and in 4 (6.6%) RM10 subjects (P = .28). There were no significant differences between the 3 groups for the frequencies of atelectasis, pneumonia, and death in the ICU. CONCLUSIONS: The routine use after heart surgery of a recruitment maneuver followed by 5 or 10 cm H2O of PEEP did not decrease the frequency of respiratory failure in obese subjects. A recruitment maneuver followed by 5 cm H2O of PEEP is inappropriate.

Lung and heart-lung transplantation for children with PAH: Dramatic benefits from the implementation of a high-priority allocation program in France.

PURPOSE: Pulmonary arterial hypertension (PAH) is rare but remains fatal in infants and children despite the advance of targeted therapies. Lung transplantation (LTx), first performed in pediatric patients in the 1980s, is, with the Potts shunt, the only potentially life-extending option in patients with end-stage PAH but is possible only in tightly selected patients. Size-matching challenges severely restrict the donor organ pool, resulting-together with peculiarities of PAH in infants-in high waitlist mortality. We aimed to investigate survival when using a high-priority allocation program (HPAP) in children with PAH listed for double-LTx or heart-LTx. METHODS: We conducted a single-center, retrospective, before-after study of consecutive children with severe Group 1 PAH listed for double-LTx or heart-LTx between 1988 and 2019. The HPAP was implemented in France in 2006 and 2007 for heart-LTx and double-LTx, respectively. RESULTS: Fifty-five children with PAH were listed for transplantation. Mean age at transplantation was 15.8±2.8 years and 72% had heart-lung transplantation. PAH was usually idiopathic (65%) or due to congenital heart disease (25%). HPAP implementation resulted in the following significant benefits: Decreased cumulative incidence of waitlist death within 1 and 2 years (p < 0.0001); increased cumulative incidence of transplantation within 6 months, from 44% to 67% (p < 0.01); and improved survival after listing (at 1, 3, and 5 years: 61%, 50%, and 44% vs. 92%, 84%, and 72% before and after HPAP implementation, respectively; p = 0.02). CONCLUSION: HPAP implementation was associated with significant improvements in access to transplantation and in survival after listing in children with end-stage PAH.

Transplantation for pulmonary arterial hypertension with congenital heart disease: Impact on outcomes of the current therapeutic approach including a high-priority allocation program.

Patients with end-stage pulmonary arterial hypertension due to congenital heart disease have limited access to heart-lung transplantation or double-lung transplantation. We aimed to assess the effects of a high-priority allocation program established in France in 2007. We conducted a retrospective study to compare waitlist and posttransplantation outcomes before versus after implementation of the high-priority allocation program. We included 67 consecutive patients (mean age at listing, 33.2 ± 10.5 years) with pulmonary arterial hypertension due to congenital heart disease listed for heart-lung transplantation or double-lung transplantation from 1997 to 2016. At one month, the incidences of transplantation and death before transplantation were 3.5% and 24.6% in 1997-2006, 4.8% and 4.9% for patients on the regular list in 2007-2016, and 41.2% and 7.4% for patients listed under the high-priority allocation program (p < .001 and p = .0001, respectively). Overall survival was higher in patients listed in 2007-2016 (84.2% and 61.2% at 1 and 10 years vs. 36.8% and 22.1%, p = .0001). Increased incidence of transplantation, decreased waiting list mortality, and improved early and long-term outcomes were observed in patients with pulmonary arterial hypertension due to congenital heart disease listed for transplantation in the recent era, characterized by implementation of a high-priority allocation program.