Expiratory abdominal muscle thickness, a new point of care ultrasound measure for respiratory muscle mass in the intensive care unit: a prospective observational cohort study.

BACKGROUND: Even if expiratory muscles are key muscles in intensive care unit (ICU) patients, the association between their thickness and mortality has never been assessed. This study aimed to determine whether expiratory abdominal muscle thickness assessed by ultrasonography (US) was associated with 28-day mortality in ICU patients. BASIC PROCEDURES: US expiratory abdominal muscle thickness was measured within the first 12 h after ICU admission. The primary endpoint was 28-day mortality. MAIN FINDINGS: In 310 analyzed patients, a thinner total abdominal expiratory muscle thickness at admission was associated with 28-day mortality (median value with interquartile range: 10.8 [10; 14.6] versus 16.5 [13.4; 20.7] mm). Total abdominal expiratory muscle thickness had an area under the curve of 0.78 [0.71;0.86] to discriminate 28-day mortality. CONCLUSIONS: US expiratory abdominal muscle thickness was associated with 28-day mortality, supporting its use in predicting ICU patient outcome.

Implementation of a regional multidisciplinary veno-venous extracorporeal membrane oxygenation unit improved survival: a historical cohort study.

PURPOSE: Veno-venous extracorporeal membrane oxygenation (vvECMO) is a highly invasive technique with a high risk of mortality. Based on reports of improved outcomes in high-volume ECMO centers, we established a regional vvECMO unit. The objective of this study was to evaluate how the vvECMO unit affected patient mortality rates. METHODS: This was a historical cohort study of all patients admitted to Dijon University Hospital and supported by vvECMO between January 2011 and June 2021. Patients managed with the vvECMO unit were compared with patients managed with non-vvECMO units. The primary outcome was 90-day mortality. RESULTS: Of 172 patients treated using vvECMO, 69% were men, and the median [interquartile range] age was 59 [48-66] yr. Of the 172 patients, 35 were treated in the vvECMO unit and 137 were treated elsewhere (110/137 before the unit was established and 27/137 after). Ninety-day mortality was lower in patients managed in the vvECMO unit (15/35, 43% vs 92/137, 67%; P = 0.005). Within the vvECMO unit, mortality rates were also lower for the subgroup of patients managed after the specialized unit was established (15/35, 43% vs 20/27, 74%; P = 0.002). After adjusting for baseline severity of illness at vvECMO initiation, the vvECMO unit was independently associated with a lower 90-day mortality rate (hazard ratio, 0.41; 95% confidence interval, 0.21 to 0.80). CONCLUSION: The establishment of a vvECMO unit was associated with reduced 90-day mortality. This improved survival may relate to patient selection, more specialized mechanical ventilation support, and/or improvement of vvECMO care.

RéSUMé: OBJECTIF: L'oxygénation par membrane extracorporelle veino-veineuse (ECMO-VV) est une technique hautement invasive qui s'accompagne d'un risque élevé de mortalité. Sur la base de comptes rendus faisant état d'améliorations des devenirs dans les centers pratiquant un volume important d'ECMO, nous avons mis en place une unité régionale d'ECMO-VV. L'objectif de cette étude était d'évaluer l'impact de l'unité d'ECMO-VV sur les taux de mortalité des patients. MéTHODE: Nous avons réalisé une étude de cohorte historique incluant tous les patients admis au CHU de Dijon et traités par ECMO-VV entre janvier 2011 et juin 2021. Les patients pris en charge par l'unité d'ECMO-VV ont été comparés aux patients pris en charge par d'autres unités. Le critère d'évaluation principal était la mortalité à 90 jours. RéSULTATS: Sur 172 patients traités par ECMO-VV, 69 % étaient des hommes et l'âge médian [écart interquartile] était de 59 [48-66] ans. Sur les 172 patients, 35 ont été traités par l'unité d'ECMO-VV et 137 ont été traités ailleurs (110/137 avant la création de l'unité et 27/137 après). La mortalité à 90 jours était plus faible chez les patients pris en charge par l'unité d'ECMO-VV (15/35, 43 % vs 92/137, 67 %; P = 0,005). Au sein de l'unité d'ECMO-VV, les taux de mortalité étaient également plus faibles pour le sous-groupe de patients pris en charge après la création de l'unité spécialisée (15/35, 43 % vs 20/27, 74 %; P = 0,002). Après ajustement pour tenir compte de la gravité initiale de la maladie à la mise en place de l'ECMO-VV, l'unité d'ECMO-VV était indépendamment associée à un taux de mortalité plus faible à 90 jours (rapport de risque, 0,41; intervalle de confiance à 95 %, 0,21 à 0,80). CONCLUSION: La mise en place d'une unité d'ECMO-VV a été associée à une réduction de la mortalité à 90 jours. Cette amélioration de la survie peut être liée à la sélection des patients, à un soutien par ventilation mécanique plus spécialisé et /ou à l'amélioration des soins d'ECMO-VV.

Fasting does not guarantee empty stomach in the intensive care unit: A prospective ultrasonographic evaluation (The NUTRIGUS study).

BACKGROUND: In the intensive care unit (ICU), a fasting period is usually respected to avoid gastric aspiration during airway management procedures. Since there are no recognised guidelines, intensive care physicians balance the aspiration risk with the negative consequences of underfeeding. Our objective was to determine the impact of fasting on gastric emptying in critically ill patients by using gastric ultrasound. MATERIAL AND METHODS: Among the 112 patients that met the inclusion criteria, 100 patients were analysed. Gastric ultrasonography was performed immediately before extubation. Patients with either 1/ an absence of visualised gastric content (qualitative evaluation) or 2/ a gastric volume < 1.5 mll/kg in case of clear fluid gastric content (quantitative evaluation) were classified as having an empty stomach. MAIN FINDINGS: In our study, twenty-six (26%) patients had a full stomach at the time of extubation. The incidence of full stomach was not significantly different between patients who fasted < 6 h or patients who fasted ≥ 6 h. Among the 57 patients receiving enteral nutrition (EN) within the last 48 h, there was no correlation between the duration of EN interruption and the GAA. The absence of EN was not associated with an empty stomach. CONCLUSION: At the time of extubation, the incidence of full stomach was high and not associated with the fasting characteristics (duration/absence of EN). Our results support the notions that fasting before airway management procedures is not a universal paradigm and that gastric ultrasound might represent a useful tool in the tailoring process. CLINICALTRIALS.GOV: NCT04245878.

Use of tracheal ultrasound combined with clinical parameters to select left double-lumen tube size: A prospective observational study.

BACKGROUND: Left double-lumen tubes (LDLTs) are used in thoracic surgery to allow one-lung ventilation. Their size is usually chosen on the basis of clinical parameters (height, sex). Double-lumen endobronchial tubes are frequently undersized/oversized, risking tube displacement or tracheal trauma. A correlation between ultrasound tracheal diameter and left main bronchus dimension has been demonstrated. OBJECTIVES: We hypothesised that the insertion of undersized/oversized double-lumen tubes is frequent when the size is selected using standard criteria, and that the use of ultrasound to estimate tracheal diameter may help to reduce the frequency of insertion of oversized tubes. DESIGN: Two-step prospective observational study. SETTING: The operating room of a French University hospital from January 2016 to February 2017. PATIENTS: We enrolled 102 and 50 consecutive patients undergoing elective thoracic surgery in Steps 1 and 2 (males 63.7 and 60.0%, age 63 (13) and 63 (11) years, height 170 (13) and 169 (9) cm, respectively). INTERVENTION: In Step 1, the size of the LDLT inserted was selected on the basis of clinical parameters. Ultrasound data about tracheal diameter were collected to determine cut-off points associating height and tracheal diameter. Cut-off values for ultrasound tracheal diameter were applied retrospectively to test their capability to reduce the insertion rate of oversized tube. In Step 2, the LDLT size was chosen according to the determined combined cut-off values. MAIN OUTCOME MEASURE: LDLT size was considered adequate if the bronchial cuff volume required for isolation of the lung (i.e. no difference between inspiratory and expiratory lung volumes) was 0.5 to 2.5 ml of air; undersized and oversized tubes required more than 2.5 ml and less than 0.5 ml, respectively. RESULTS: In Step 1, LDLT size was appropriate/undersized/oversized in 40 (39.2%)/23 (22.6%)/39 (38.6%) of patients. Cut-off values derived from ultrasound measurements would have reduced the use of oversized tubes by 20.6% (P < 0.001). In Step 2, the frequency of use of adequately sized tubes increased (86.0 vs. 39.2%, P < 0.001), and the frequency of insertion of oversized and undersized tubes decreased (6.0 vs. 38.2% and 8.0 vs. 22.6%, both P < 0.001). CONCLUSION: Combining ultrasound measurement of tracheal diameter and clinical parameters improves the choice of LDLT size.

Lung ultrasound for diagnosis and monitoring of ventilator-associated pneumonia.

Ventilator-associated pneumonia (VAP) is the most frequent nosocomial infection in intensive care units (ICU) and is associated with increased mortality, use of antimicrobials, longer mechanical ventilation, and higher healthcare costs. Lung ultrasonography (LUS) can be used at the bedside and gained widespread acceptance in ICU. Although the visualization of a single LUS sign cannot be considered specific for a diagnosis, clinically-driven LUS examination in particular setting and clinical conditions allow ruling in or out quickly and accurately several causes of acute respiratory failure. This article reviews LUS signs for VAP diagnosis and summarizes the studies testing LUS for VAP diagnosis and monitoring. Many VAP occurs in already injured regions, thus presence of lobar consolidation is not enough to affirm VAP. However, a linear/arborescent air-bronchogram confirms the diagnosis of VAP with a good specificity, a normal LUS rules out the diagnosis of VAP (in experimented hands). LUS, thanks to its bedside ready availability, has the potential to become a key tool in early VAP diagnosis. LUS could ideally represent the decision-making tool for antimicrobial therapy administration in the timeframe of the technical time required for bronchoalveolar lavage analysis. A systematic approach for diagnosis and monitoring of VAP with LUS is also proposed in this review. But specific data on LUS specificity and sensitivity for the diagnosis of VAP are still lacking and should be investigated.