Béatrice Riu

Effect of Noninvasive Ventilation on Tracheal Reintubation Among Patients With Hypoxemic Respiratory Failure Following Abdominal Surgery: A Randomized Clinical Trial

IMPORTANCE It has not been established whether noninvasive ventilation (NIV) reduces the need for invasive mechanical ventilation in patients who develop hypoxemic acute respiratory failure after abdominal surgery. OBJECTIVE To evaluate whether noninvasive ventilation improves outcomes among patients developing hypoxemic acute respiratory failure after abdominal surgery. DESIGN, SETTING, AND PARTICIPANTS Multicenter, randomized, parallel-group clinical trial conducted between May 2013 and September 2014 in 20 French intensive care units among 293 patients who had undergone abdominal surgery and developed hypoxemic respiratory failure (partial oxygen pressure <60 mm Hg or oxygen saturation [SpO2] ≤90% when breathing room air or <80 mm Hg when breathing 15 L/min of oxygen, plus either [1] a respiratory rate above 30/min or [2] clinical signs suggestive of intense respiratory muscle work and/or labored breathing) if it occurred within 7 days after surgical procedure. INTERVENTIONS Patients were randomly assigned to receive standard oxygen therapy (up to 15 L/min to maintain SpO2 of 94% or higher) (n = 145) or NIV delivered via facial mask (inspiratory pressure support level, 5-15 cm H2O; positive end-expiratory pressure, 5-10 cm H2O; fraction of inspired oxygen titrated to maintain SpO2 ≥94%) (n = 148). MAIN OUTCOMES AND MEASURES The primary outcome was tracheal reintubation for any cause within 7 days of randomization. Secondary outcomes were gas exchange, invasive ventilation-free days at day 30, health care-associated infections, and 90-day mortality. RESULTS Among the 293 patients (mean age, 63.4 [SD, 13.8] years; n=224 men) included in the intention-to-treat analysis, reintubation occurred in 49 of 148 (33.1%) in the NIV group and in 66 of 145 (45.5%) in the standard oxygen therapy group within+ 7 days after randomization (absolute difference, -12.4%; 95% CI, -23.5% to -1.3%; P = .03). Noninvasive ventilation was associated with significantly more invasive ventilation-free days compared with standard oxygen therapy (25.4 vs 23.2 days; absolute difference, -2.2 days; 95% CI, -0.1 to 4.6 days; P = .04), while fewer patients developed health care-associated infections (43/137 [31.4%] vs 63/128 [49.2%]; absolute difference, -17.8%; 95% CI, -30.2% to -5.4%; P = .003). At 90 days, 22 of 148 patients (14.9%) in the NIV group and 31 of 144 (21.5%) in the standard oxygen therapy group had died (absolute difference, -6.5%; 95% CI, -16.0% to 3.0%; P = .15). There were no significant differences in gas exchange. CONCLUSIONS AND RELEVANCE Among patients with hypoxemic respiratory failure following abdominal surgery, use of NIV compared with standard oxygen therapy reduced the risk of tracheal reintubation within 7 days. These findings support use of NIV in this setting. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT01971892.

Usefulness of Cardiothoracic Chest Ultrasound in the Management of Acute Respiratory Failure in Critical Care Practice

BACKGROUND This study investigated the clinical relevance of early general chest ultrasonography (ie, heart and lung recordings) in patients in the ICU with acute respiratory failure (ARF). METHODS We prospectively compared this diagnostic approach (ultrasound) to a routine evaluation established from clinical, radiologic, and biologic data (standard). Subjects were patients consecutively admitted to the ICU of a university teaching hospital during a 1-year period. Inclusion criteria were age ≥ 18 years and the presence of severe ARF criteria to justify ICU admission. We compared the diagnostic approaches and the final diagnosis determined by a panel of experts. RESULTS Seventy-eight patients were included (age, 70 ± 18 years; sex ratio, 1). Three patients given two or more simultaneous diagnoses were subsequently excluded. The ultrasound approach was more accurate than the standard approach (83% vs 63%, respectively; P < .02). Receiver operating characteristic curve analysis showed greater diagnostic performance of ultrasound in cases of pneumonia (standard, 0.74 ± 0.12; ultrasound, 0.87 ± 0.14; P < .02), acute hemodynamic pulmonary edema (standard, 0.79 ± 0.11; ultrasound, 0.93 ± 0.08; P < .007), decompensated COPD (standard, 0.8 ± 0.09; ultrasound, 0.92 ± 0.15; P < .05), and pulmonary embolism (standard, 0.65 ± 0.12; ultrasound, 0.81 ± 0.17; P < .04). Furthermore, we found that the use of ultrasound data could have significantly improved the initial treatment. CONCLUSIONS The use of cardiothoracic ultrasound appears to be an attractive complementary diagnostic tool and seems able to contribute to an early therapeutic decision based on reproducible physiopathologic data.

Integrated Use of Bedside Lung Ultrasound and Echocardiography in Acute Respiratory Failure : A Prospective Observational Study in ICU

BACKGROUND It has been suggested that the complementary use of echocardiography could improve the diagnostic accuracy of lung ultrasonography (LUS) in patients with acute respiratory failure (ARF). Nevertheless, the additional diagnostic value of echocardiographic data when coupled with LUS is still debated in this setting. The aim of the current study was to compare the diagnostic accuracy of LUS and an integrative cardiopulmonary ultrasound approach (thoracic ultrasonography [TUS]) in patients with ARF. METHODS We prospectively recruited patients consecutively admitted for ARF to the ICU of a university teaching hospital over a 12-month period. Inclusion criteria were age ≥ 18 years and the presence of criteria for severe ARF justifying ICU admission. We compared both LUS and TUS approaches and the final diagnosis determined by a panel of experts using machine learning methods to improve the accuracy of the final diagnostic classifiers. RESULTS One hundred thirty-six patients were included (age, 68 ± 15 years; sex ratio, 1). A three-dimensional partial least squares and multinomial logistic regression model was developed and subsequently tested in an independent sample of patients. Overall, the diagnostic accuracy of TUS was significantly greater than LUS (P < .05, learning and test sample). Comparisons between receiver operating characteristic curves showed that TUS significantly improves the diagnosis of cardiogenic edema (P < .001, learning and test samples), pneumonia (P < .001, learning and test samples), and pulmonary embolism (P < .001, learning sample). CONCLUSIONS This study demonstrated for the first time to our knowledge a significantly better performance of TUS than LUS in the diagnosis of ARF. The value of the TUS approach was particularly important to disambiguate cases of hemodynamic pulmonary edema and pneumonia. We suggest that the bedside use of artificial intelligence methods in this setting could pave the way for the development of new clinically relevant integrative diagnostic models.

Predicting preload responsiveness using simultaneous recordings of inferior and superior vena cavae diameters

IntroductionEchocardiographic indices based on respiratory variations of superior and inferior vena cavae diameters (ΔSVC and ΔIVC, respectively) have been proposed as predictors of fluid responsiveness in mechanically ventilated patients, but they have never been compared simultaneously in the same patient sample. The aim of this study was to compare the predictive value of these echocardiographic indices when concomitantly recorded in mechanically ventilated septic patients.MethodsSeptic shock patients requiring hemodynamic monitoring were prospectively enrolled over a 1-year period in a mixed medical surgical ICU of a university teaching hospital (Toulouse, France). All patients were mechanically ventilated. Predictive indices were obtained by transesophageal and transthoracic echocardiography and were calculated as follows: (Dmax - Dmin)/Dmax for ΔSVC and (Dmax - Dmin)/Dmin for ΔIVC, where Dmax and Dmin are the maximal and minimal diameters of SVC and IVC. Measurements were performed at baseline and after a 7-ml/kg volume expansion using a plasma expander. Patients were separated into responders (increase in cardiac index ≥15%) and nonresponders (increase in cardiac index <15%).ResultsAmong 44 included patients, 26 (59%) patients were responders (R). ΔSVC was significantly more accurate than ΔIVC in predicting fluid responsiveness. The areas under the receiver operating characteristic curves for ΔSVC and ΔIVC regarding assessment of fluid responsiveness were significantly different (0.74 (95% confidence interval (CI): 0.59 to 0.88) and 0.43 (95% CI: 0.25 to 0.61), respectively (P = 0.012)). No significant correlation between ΔSVC and ΔIVC was found (r = 0.005, P = 0.98). The best threshold values for discriminating R from NR was 29% for ΔSVC, with 54% sensitivity and 89% specificity, and 21% for ΔIVC, with 38% sensitivity and 61% specificity.ConclusionsΔSVC was better than ΔIVC in predicting fluid responsiveness in our cohort. It is worth noting that the sensitivity and specificity values of ΔSVC and ΔIVC for predicting fluid responsiveness were lower than those reported in the literature, highlighting the limits of using these indices in a heterogeneous sample of medical and surgical septic patients.

Disruption of posteromedial large-scale neural communication predicts recovery from coma

Objective: We hypothesize that the major consciousness deficit observed in coma is due to the breakdown of long-range neuronal communication supported by precuneus and posterior cingulate cortex (PCC), and that prognosis depends on a specific connectivity pattern in these networks. Methods: We compared 27 prospectively recruited comatose patients who had severe brain injury (Glasgow Coma Scale score <8; 14 traumatic and 13 anoxic cases) with 14 age-matched healthy participants. Standardized clinical assessment and fMRI were performed on average 4 ± 2 days after withdrawal of sedation. Analysis of resting-state fMRI connectivity involved a hypothesis-driven, region of interest–based strategy. We assessed patient outcome after 3 months using the Coma Recovery Scale–Revised (CRS-R). Results: Patients who were comatose showed a significant disruption of functional connectivity of brain areas spontaneously synchronized with PCC, globally notwithstanding etiology. The functional connectivity strength between PCC and medial prefrontal cortex (mPFC) was significantly different between comatose patients who went on to recover and those who eventually scored an unfavorable outcome 3 months after brain injury (Kruskal-Wallis test, p < 0.001; linear regression between CRS-R and PCC-mPFC activity coupling at rest, Spearman ρ = 0.93, p < 0.003). Conclusion: In both etiology groups (traumatic and anoxic), changes in the connectivity of PCC-centered, spontaneously synchronized, large-scale networks account for the loss of external and internal self-centered awareness observed during coma. Sparing of functional connectivity between PCC and mPFC may predict patient outcome, and further studies are needed to substantiate this potential prognosis biomarker.

Alteration of plasma phospholipid fatty acid profile in patients with septic shock.

In septic shock patients, alterations of plasma phospholipid fatty acid profile have never been described. The purpose of this monocentric, non-interventional, observational prospective study was to describe this fatty acid profile in the early phase of septic shock in intensive care unit. Thirty-seven adult patients with septic shock were included after the first day of stay in intensive care unit, before any form of artificial nutritional support. Plasma phospholipid fatty acid composition was determined by gas chromatography. All biological data from patients with septic shock were compared with laboratory reference values. Patients presented hypocholesterolemia and hypertriglyceridemia. They had low concentrations of phospholipid fatty acids specifically n-6 and n-3 polyunsaturated fatty acids (PUFAs) with a high n-6/n-3 ratio. Plasma phospholipid PUFA concentrations were strongly correlated with cholesterolemia. PUFAs/SFAs (saturated fatty acids) and PUFAs/MUFAs (monounsaturated fatty acids) ratios were low because of low percentage of n-6 and n-3 PUFAs and high percentage of SFAs and MUFAs. Low levels of plasma long chain PUFAs (≥20 carbons) were significantly associated with mortality at 28th day. In conclusion, plasma phospholipid FA profile of septic patients is very characteristic, close to that of acute respiratory distress syndrome and mortality is associated with long chain PUFA decrease. This profile could be explained by numerous non-exclusive physio-pathological processes 1) an activation of hepatic de novo lipogenesis that could contribute to hepatic steatosis, 2) an elevated adipose tissue lipolysis, 3) an increased free radical attack of FA by oxidative stress, 4) an over-production of inflammatory lipid mediators.

Combined Thoracic Ultrasound Assessment during a Successful Weaning Trial Predicts Postextubation Distress

Background: Recent studies suggest that isolated sonographic assessment of the respiratory, cardiac, or neuromuscular functions in mechanically ventilated patients may assist in identifying patients at risk of postextubation distress. The aim of the present study was to prospectively investigate the value of an integrated thoracic ultrasound evaluation, encompassing bedside respiratory, cardiac, and diaphragm sonographic data in predicting postextubation distress. Methods: Longitudinal ultrasound data from 136 patients who were extubated after passing a trial of pressure support ventilation were measured immediately after the start and at the end of this trial. In case of postextubation distress (31 of 136 patients), an additional combined ultrasound assessment was performed while the patient was still in acute respiratory failure. We applied machine-learning methods to improve the accuracy of the related predictive assessments. Results: Overall, integrated thoracic ultrasound models accurately predict postextubation distress when applied to thoracic ultrasound data immediately recorded before the start and at the end of the trial of pressure support ventilation (learning sample area under the curve: start, 0.921; end, 0.951; test sample area under the curve: start, 0.972; end, 0.920). Among integrated thoracic ultrasound data, the recognition of lung interstitial edema and the increased telediastolic left ventricular pressure were the most relevant predictive factors. In addition, the use of thoracic ultrasound appeared to be highly accurate in identifying the causes of postextubation distress. Conclusions: The decision to attempt extubation could be significantly assisted by an integrative, dynamic, and fully bedside ultrasonographic assessment of cardiac, lung, and diaphragm functions.

Oxygen challenge test in septic shock patients: prognostic value and influence of respiratory status.

ABSTRACT Transcutaneous oxygen pressure (PtcO2) value in response to an increase of FiO2 or oxygen challenge test (OCT) in ventilated patients has been reported to be related to peripheral perfusion and outcome during septic shock. However, patients with sepsis-related acute respiratory distress syndrome could demonstrate compromised arterial oxygenation with OCT impairment decoupled to circulatory failure. The aims of this study were to confirm the prognostic value of OCT and to explore the influence of respiratory status on OCT results. This was a prospective study set in an intensive care unit of a tertiary teaching hospital. Fifty-six mechanically ventilated patients with septic shock criteria were studied. Transcutaneous oxygen pressure was measured at baseline and after OCT, at intensive care unit admittance (T0), and 24 h later (T24). Survival at day 28 and hemodynamic and respiratory parameters were analyzed and compared according to outcome and respiratory status. Central hemodynamic parameters or static transcutaneous data did not differ between survivors and nonsurvivors at enrollment. The OCT was statistically different at T24 according to outcome (P < 0.001), but sensitivity was low (53%). Moreover, patients with low OCT results at T24 exhibited more severe respiratory failure (P < 0.01). The OCT at T24 is related to outcome but is influenced by the severity of respiratory failure. Our results suggest considering with caution hemodynamic management based on OCT in septic shock patients with altered pulmonary function.

LEFT VENTRICULAR-RIGHT ATRIAL COMMUNICATION WITH THIRD-DEGREE ATRIOVENTRICULAR BLOCK AFTER THORACIC TRAUMA

BACKGROUND Intracardiac shunts are rare but very serious lesions after non-penetrating chest trauma. Their diagnosis is difficult. This pathology often goes unrecognized in the context of multiple trauma. CASE REPORT We report the case of a 21-year-old man involved in a motor vehicle crash who presented with multiple injuries including myocardial contusion, severe brain injury, multiple pelvic fractures, closed femur fracture, bilateral lung contusion with a right pneumothorax, and intra-abdominal injuries. Three days after the initial event, a new cardiac murmur and complete heart block appeared. Transthoracic echocardiography (echo) followed by transesophageal echo revealed a high-velocity flow communication between the left ventricle and the right atrium. The patient underwent delayed cardiac surgery due to other unstable injuries. The hospital course was prolonged but favorable, and the patient left the hospital 1 month later without any neurologic or cardiologic after-effect. CONCLUSION This case highlights the potential for cardiac complications to occur in any patient with serious thoracic trauma. Transesophageal echo should be performed on any trauma patient with electrocardiographic abnormalities.

E/Ea ratio could not predict fluid response in ICU mechanically ventilated patients

Transthoracic echocardiography (TTE) is now widely used in the ICU to assess hemodynamic status. Combined mitral index measured by TTE, as the mitral Doppler inflow E wave velocity to annular tissue Doppler Ea wave velocity ratio (E/Ea), is a reliable diastolic indicator in cardiologic patients. In ICU, E/Ea has only been investigated as a pulmonary arterial occlusion pressure surrogate which poorly reflects fluid responsiveness (FR). Therefore, the aim of this study was to evaluate the reliability of E/Ea to FR in the setting of ICU ventilated patients.