Barotrauma in COVID-19 acute respiratory distress syndrome: retrospective analysis of the COVADIS prospective multicenter observational database.

BACKGROUND: Despite evidence suggesting a higher risk of barotrauma during COVID-19-related acute respiratory distress syndrome (ARDS) compared to ARDS due to other causes, data are limited about possible associations with patient characteristics, ventilation strategy, and survival. METHODS: This prospective observational multicenter study included consecutive patients with moderate-to-severe COVID-19 ARDS requiring invasive mechanical ventilation and managed at any of 12 centers in France and Belgium between March and December 2020. The primary objective was to determine whether barotrauma was associated with ICU mortality (censored on day 90), and the secondary objective was to identify factors associated with barotrauma. RESULTS: Of 586 patients, 48 (8.2%) experienced barotrauma, including 35 with pneumothorax, 23 with pneumomediastinum, 1 with pneumoperitoneum, and 6 with subcutaneous emphysema. Median time from mechanical ventilation initiation to barotrauma detection was 3 [0-17] days. All patients received protective ventilation and nearly half (23/48) were in volume-controlled mode. Barotrauma was associated with higher hospital mortality (P < 0.001) even after adjustment on age, sex, comorbidities, PaO2/FiO2 at intubation, plateau pressure at intubation, and center (P < 0.05). The group with barotrauma had a lower mean body mass index (28.6 ± 5.8 vs. 30.3 ± 5.9, P = 0.03) and a higher proportion of patients given corticosteroids (87.5% vs. 63.4%, P = 0.001). CONCLUSION: Barotrauma during mechanical ventilation for COVID-19 ARDS was associated with higher hospital mortality.

The accuracy of intensive care nurses' interpretation of chest radiographs to recognise misplacement of endotracheal and nasogastric tubes after a single training session and comparison with residents' interpretation.

BACKGROUND: Misplacements of endotracheal and nasogastric tubes are frequent encounters in critically ill patients. OBJECTIVES: The purpose of this study was to assess the effectiveness of a single standardised training session on the ability of intensive care registered nurses (RNs) to recognise the misplacement of endotracheal and nasogastric tubes on bedside chest radiographs of patients in intensive care units (ICUs). METHODS: In eight French ICUs, RNs received a 110-min standardised teaching on the position of endotracheal and nasogastric tubes on chest radiographs. Their knowledge was evaluated within the subsequent weeks. For 20 chest radiographs, each with an endotracheal and nasogastric tube, RNs had to indicate whether each tube was in the proper or incorrect position. Training success was defined as >90% for the lower bound of the 95% confidence interval (95% CI) of the mean correct response rate (CRR). Residents of the participating ICUs underwent the same evaluation (without prior specific training). RESULTS: In total, 181 RNs were trained and evaluated and 110 residents were evaluated. The global mean CRR for RNs was 84.6% (95% CI: 83.3-85.9), significantly higher than for residents (81.4% [95% CI: 79.7-83.2]) (P < 0.0001). The mean CRR for RNs and residents was 95.9% (93.9-98.0) and 97.0% (94.7-99.3) for misplaced nasogastric tubes (P = 0.54), 86.8% (85.2-88.5) and 82.6% (79.4-85.7) (P = 0.07) for nasogastric tubes in the correct position, 86.6% (83.8-89.3) and 62.7% (57.9-67.5) for misplaced endotracheal tubes (P < 0.0001), and 79.1% (76.6-81.6) and 84.7% (82.1-87.2) for endotracheal tubes in the correct position (P = 0.01), respectively. CONCLUSIONS: The ability of trained RNs to detect tube misplacement did not reach the predetermined arbitrary level, indicating training success. Their mean CRR was higher than that for residents and was considered satisfactory for detecting misplaced nasogastric tubes. This finding is encouraging but insufficient to ensure patient safety. Transferring responsibility for reading radiographs to detect the misplacement of endotracheal tubes to intensive care RNs will need a more advanced or more in-depth teaching method.

Oxygen reserve index for non-invasive early hypoxemia detection during endotracheal intubation in intensive care: the prospective observational NESOI study.

BACKGROUND: To evaluate the ability of the oxygen reserve index (ORI) to predict the occurrence of mild hypoxemia (defined as SpO2 < 97%) during endotracheal intubation (ETI) of patients in the intensive care unit (ICU). METHODS: This observational single-centre study included patients without hypoxemia (defined as SpO2/FiO2 > 214) who required ETI in the ICU. Patients were followed during preoxygenation and ETI then until hospital discharge and/or day 28. We recorded cases of mild hypoxemia, moderate (SpO2 < 90%) and severe (SpO2 < 80%) hypoxemia, moderate arterial hypotension (systolic arterial pressure < 90 mmHg), oesophageal intubation, aspiration, cardiac arrest, and death. RESULTS: Between January 2019 and July 2020, 56 patients were included prospectively and 51 patients were analysed. Twenty patients had mild hypoxemia between the end of preoxygenation and the end of intubation; in 10 of these patients, the decrease in SpO2 below 97% was preceded by an ORI < 0.4, the median time difference being 81 s [interquartile range, 34-146]. By multivariable analysis, a higher ORI (by 0.1 increase) value during preoxygenation was associated with absence of hypoxemia (odds ratio, 0.76; 95% confidence interval, 0.61;0.95; P = 0.0141). CONCLUSION: In non-hypoxemic patients, the 81-s [34-146] median time between the ORI decrease below 0.4 and the SpO2 decrease below 97% during apnoea may allow preventive action. A higher ORI value during preoxygenation was independently protective against hypoxemia. Whether these findings also apply to hypoxemic patients, and the clinical impact of a preoxygenation strategy based on ORI monitoring, remain to be evaluated prospectively. Trial Registration ClinicalTrial.gov, #NCT03600181.

Identifying Clinical Phenotypes in Moderate to Severe Acute Respiratory Distress Syndrome Related to COVID-19: The COVADIS Study.

Objectives: Different phenotypes have been identified in acute respiratory distress syndrome (ARDS). Existence of several phenotypes in coronavirus disease (COVID-19) related acute respiratory distress syndrome is unknown. We sought to identify different phenotypes of patients with moderate to severe ARDS related to COVID-19. Methods: We conducted an observational study of 416 COVID-19 patients with moderate to severe ARDS at 21 intensive care units in Belgium and France. The primary outcome was day-28 ventilatory free days. Secondary outcomes were mortality on day 28, acute kidney injury, acute cardiac injury, pulmonary embolism, and deep venous thrombosis. Multiple factor analysis and hierarchical classification on principal components were performed to distinguish different clinical phenotypes. Results: We identified three different phenotypes in 150, 176, and 90 patients, respectively. Phenotype 3 was characterized by short evolution, severe hypoxemia, and old comorbid patients. Phenotype 1 was mainly characterized by the absence of comorbidities, relatively high compliance, and long duration of symptoms, whereas phenotype 2 was characterized female sex, and the presence of mild comorbidities such as uncomplicated diabetes or chronic hypertension. The compliance in phenotype 2 was lower than that in phenotype 1, with higher plateau and driving pressure. Phenotype 3 was associated with higher mortality compared to phenotypes 1 and 2. Conclusions: In COVID-19 patients with moderate to severe ARDS, we identified three clinical phenotypes. One of these included older people with comorbidities who had a fulminant course of disease with poor prognosis. Requirement of different treatments and ventilatory strategies for each phenotype needs further investigation.