Persistent diaphragm dysfunction after cardiac surgery is associated with adverse respiratory outcomes: a prospective observational ultrasound study.

BACKGROUND: Transient diaphragm dysfunction is common during the first week after cardiac surgery; however, the precise incidence, risk factors, and outcomes of persistent diaphragm dysfunction are not well described. METHODS: In a single-centre prospective cohort study, we included all consecutive patients over 18 yr who underwent elective cardiac surgery. Diaphragm function was evaluated with ultrasound (M-mode) by recording the excursion of both hemidiaphragms at two different time points: preoperatively and after the seventh postoperative day in patients breathing without assistance. Significant diaphragm dysfunction after the seventh day of the index cardiac surgery was defined as a decrease in diaphragm excursion below the lower limit of normal: at rest, < 9 mm for women and < 10 mm for men; after a sniff test, < 16 mm for women and < 18 mm for men. RESULTS: Overall, 122 patients were included in the analysis. The median [interquartile range (IQR)] age was 69 [59-74] years and 96/122 (79%) were men. Ten (8%) patients had diaphragm dysfunction after the seventh postoperative day. We did not identify risk factors for persistent diaphragm dysfunction. Persistent diaphragm dysfunction was associated with a longer median [IQR] duration of noninvasive (8 [0-34] vs 0 [0-0] hr; difference in medians, 8 hr; 95% confidence interval [CI], 0 to 22; P < 0.001) and invasive mechanical ventilation (5 [3-257] vs 3[2-4] hr; difference in medians, 2 hr; 95% CI, 0.5 to 41; P = 0.008); a higher reintubation rate (4/10, 40% vs 1/112, 0.9%; relative risk, 45; 95% CI, 7.1 to 278; P < 0.0001), a higher incidence of pneumonia (4/10 [40%] vs 7/112 [6%]; relative risk, 6; 95% CI, 2 to 16; P < 0.001), and longer median [IQR] length of stay in the intensive care unit (8 [5-29] vs 4 [2-6] days; difference in medians, 4 days; 95% CI, 2 to 12; P = 0.002). CONCLUSION: The incidence of persistent diaphragm dysfunction was 8% in patients undergoing elective cardiac surgery and was associated with adverse respiratory outcomes. STUDY REGISTRATION: ClinicalTrials.gov (NCT04276844); prospectively registered 19 February 2020.

RéSUMé: CONTEXTE: Un dysfonctionnement transitoire du diaphragme est fréquent au cours de la première semaine après une chirurgie cardiaque. Toutefois, l'incidence précise, les facteurs de risque et les devenirs liés à un dysfonctionnement persistant du diaphragme ne sont pas bien décrits. MéTHODE: Dans une étude de cohorte prospective monocentrique, nous avons inclus tous les patients consécutifs de plus de 18 ans qui ont bénéficié d'une chirurgie cardiaque non urgente. La fonction du diaphragme a été évaluée à l'échographie (mode M) en enregistrant l'excursion des deux hémidiaphragmes à deux moments différents : avant l'opération et après le septième jour postopératoire chez les patients respirant sans assistance. Un dysfonctionnement significatif du diaphragme après le septième jour de la chirurgie cardiaque initiale a été défini comme une diminution de l'excursion diaphragmatique en dessous de la limite inférieure de la normale, soit : au repos, < 9 mm pour les femmes et < 10 mm pour les hommes; après un test de reniflement, < 16 mm pour les femmes et < 18 mm pour les hommes. RéSULTATS: Au total, 122 patients ont été inclus dans l'analyse. L'âge médian des patients (écart interquartile [ÉIQ]) était de 69 ans [59-74] ans et 96/122 (79 %) étaient des hommes. Dix (8 %) patients ont présenté un dysfonctionnement du diaphragme après le septième jour postopératoire. Nous n'avons pas identifié de facteurs de risque de dysfonctionnement persistant du diaphragme. Un dysfonctionnement persistant du diaphragme était associé à : une durée médiane [ÉIQ] de ventilation non invasive (8 [0­34] vs 0 [0­0] h; différence dans les médianes, 8 heures; intervalle de confiance [IC] à 95 %, 0 à 22; P < 0,001) et de ventilation mécanique invasive (5 [3­257] vs 3[2­4] h; différence dans les médianes, 2 heures; IC 95 %, 0,5 à 41; P = 0,008) plus longues, un taux de réintubation plus élevé (4/10, 40 % vs 1/112, 0,9 %; risque relatif, 45; IC 95 %, 7,1 à 278; P < 0,0001), une incidence plus élevée de pneumonie (4/10 [40 %] vs 7/112 [6 %]; risque relatif, 6; IC 95 %, de 2 à 16; P < 0,001), et une durée de séjour médiane [ÉIQ] plus longue à l'unité de soins intensifs (8 [5-29] vs 4 [2­6] jours; différence en médianes, 4 jours; IC 95 %, 2 à 12; P = 0,002). CONCLUSION: L'incidence de dysfonctionnement persistant du diaphragme était de 8 % chez les patients bénéficiant d'une chirurgie cardiaque non urgente et était associée à des issues respiratoires indésirables. ENREGISTREMENT DE L'éTUDE: ClinicalTrials.gov (NCT04276844); enregistrée prospectivement le 19 février 2020.

Use of Almitrine and Inhaled Nitric Oxide in ARDS Due to COVID-19.

Introduction: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is manifested by an acute respiratory distress syndrome (ARDS) with intense inflammation and endothelial dysfunction leading to particularly severe hypoxemia. We hypothesized that an impaired hypoxic pulmonary vasoconstriction aggravates hypoxemia. The objective of the study was to test the effect of two pulmonary vasoactive drugs on patient oxygenation. Methods: Observational, single-center, open-label study in one intensive care unit (ICU) of the Paris area, realized in April 2020. Eligible patients had coronavirus disease 2019 (COVID-19) and moderate to severe ARDS [arterial partial pressure of oxygen/fraction of inspired oxygen (PaO2/FiO2) <200 mmHg] despite conventional protective ventilation. Exclusion criteria included pulmonary artery hypertension defined by a pulmonary artery systolic pressure (PAPs) >45 mmHg. The assessment of oxygenation was based on PaO2/FiO2 at (1) baseline, then after (2) 30 min of inhaled nitric oxide (iNO) 10 ppm alone, then (3) 30 min combination of iNO + almitrine infusion 8 µg/kg/min, then (4) 30 min of almitrine infusion alone. Results: Among 20 patients requiring mechanical ventilation during the study period, 12 met the inclusion criteria. Baseline PaO2/FiO2 was 146 ± 48 mmHg. When iNO was combined with almitrine, PaO2/FiO2 rose to 255 ± 90 mmHg (+80 ± 49%, p = 0.005), also after almitrine alone: 238 ± 98 mmHg (+67 ± 75%, p = 0.02), but not after iNO alone: 185 ± 73 mmHg (+30 ± 5%, p = 0.49). No adverse events related to almitrine infusion or iNO was observed. Conclusion: Combining iNO and infused almitrine improved the short-term oxygenation in patients with COVID-19-related ARDS. This combination may be of interest when first-line therapies fail to restore adequate oxygenation. These findings argue for an impaired pulmonary hypoxic vasoconstriction in these patients.

Virtual reality vs. Kalinox® for management of pain in intensive care unit after cardiac surgery: a randomized study.

INTRODUCTION: The management of pain and anxiety remains a challenge in the intensive care unit. By distracting patients, virtual reality (VR) may have a role in painful procedures. We compared VR vs. an inhaled equimolar mixture of N2O and O2 (Kalinox®) for pain and anxiety management during the removal of chest drains after cardiac surgery. METHODS: Prospective, non-inferiority, open-label study. Patients were randomized, for Kalinox® or VR session during drain removal. The analgesia/nociception index (ANI) was monitored during the procedure for objective assessment of pain and anxiety. The primary endpoint was the ΔANI (ANImin - ANI0) during the procedure, based on ANIm (average on 4 min). We prespecified VR as non-inferior to Kalinox® with a margin of 3 points. Self-reported pain and anxiety were also analysed using numeric rate scale (NRS). RESULTS: 200 patients were included, 99 in the VR group and 101 in the Kalinox® group; 90 patients were analysed in both groups in per-protocol analysis. The median age was 68.0 years [60.0-74.8]. The ΔANI was - 15.1 ± 12.9 in the Kalinox® group and - 15.7 ± 11.6 in the VR group (NS). The mean difference was, therefore, - 0.6 [- 3.6 to 2.4], including the non-inferiority margin of 3. Patients in the VR group had a significantly higher pain NRS scale immediately after the drain removal, 5.0 [3.0-7.0] vs. 3.0 [2.0-6.0], p = 0.009, but no difference 10 min after. NRS of anxiety did not differ between the two groups. CONCLUSION: Based on the ANI, the current study showed that VR did not reach the statistical requirements for a proven non-inferiority vs. Kalinox® in managing pain and anxiety during chest drain removal. Moreover, VR was less effective based on NRS. More studies are needed to determine if VR might have a place in the overall approach to pain and anxiety in intensive care units. Trial registration NCT, NCT03956264. Registered 20 May 2019, https://clinicaltrials.gov/ct2/show/NCT03956264.