Background Diagnosis of a mechanical mitral valve prosthesis thrombosis is currently made with transthoracic Doppler echocardiography and occasionally with fluoroscopy. However, identifying a thrombus on a valve prosthesis may be difficult, especially if the thrombus is nonobstructive. To prospectively define the role of transesophageal echocardiography for identification of nonobstructive thrombi, we studied a series of patients in whom the prosthetic valve was considered to function normally on clinical examination and transthoracic echocardiography. Methods and Results One hundred fourteen consecutive patients with mechanical mitral valve prosthesis were investigated by both transthoracic echocardiography and transesophageal echocardiography. These examinations were performed for recent systemic emboli (15 patients), fever of unknown etiology (11 patients), routine postoperative evaluation (56 patients), and other reasons (32 patients). Based on transthoracic echo diagnosis, all prostheses were considered normal. Yet, in 20 patients transesophageal echocardiography revealed the presence of a 2- to 15-mm-long mobile thrombus localized on the atrial surface of the prosthesis. When compared with the remaining 94 patients with no visible thrombi, there was no significant difference between the two groups in terms of incidence of atrial fibrillation (65% versus 52%), left atrial size (48±9 versus 51±13 mm), left ventricular end-diastolic diameter (49±10 versus 51±13 mm) and fractional shortening (28±9% versus 31±10%), presence of spontaneous contrast in the left atrium (40% versus 41%), transprosthetic mean pressure gradient (4.0±1.4 versus 3.9±1.5 mm Hg), or the type of prosthesis used. After we discovered a nonobstructive thrombosis, patients were treated with heparin (n=9) or oral anticoagulation (n=11). The presence of a localized thrombus was confirmed in 3 patients who were operated on. In the present study, evolution appeared to depend on thrombus size: of 14 patients exhibiting a small (<5 mm) thrombus, 10 had an uneventful course, whereas 5 of 6 patients with a large (≥5 mm) thrombus developed complications or died. Conclusions Transesophageal echocardiography appears to be a reliable method to diagnose thrombi on a mechanical mitral valve prosthesis, even when transthoracic Doppler echocardiographic parameters appear to be normal. Transesophageal echo assessment of thrombus size may be helpful in deciding whether a patient with mitral prosthesis should be treated by anticoagulation, thrombolysis, or valve rereplacement. .
L'évaluation des pressions de remplissage du ventricule gauche (VG) est essentielle pour déterminer une éventuelle participation cardiaque à un tableau d'insuffisance respiratoire aiguë. Elle repose traditionnellement sur la mesure invasive de la pression artérielle pulmonaire d'occlusion par cathétérisme droit. L'échocardiographie-doppler est une alternative avantageuse qui fournit en outre des informations anatomiques et fonctionnelles sur le cœur et les gros vaisseaux. Le doppler pulsé appliqué à la valve mitrale et aux veines pulmonaires fournit des indices simples à mesurer qui permettent d'évaluer de manière semi-quantitative le niveau des pressions de remplissage du VG. Leur précision s'accroît s'il existe une dysfonction systolique du VG. Les nouveaux indices doppler qui évaluent plus spécifiquement les propriétés diastoliques du VG (doppler tissulaire à l'anneau mitral, vitesse de propagation en TM couleur) peuvent être combinés aux paramètres doppler classiques pour affiner cette évaluation. L'échocardiographie permet également une analyse complète de la fonction de chaque ventricule, l'identification d'une cardiopathie gauche ou droite, voire une pathologie du cœur ou des gros vaisseaux à l'origine de l'épisode d'insuffisance respiratoire aiguë. C'est pourquoi, l'échocardiographie-doppler est un examen de première ligne essentiel dans la prise en charge des patients admis en réanimation pour défaillance respiratoire. Elle est particulièrement utile dans la démarche diagnostique face à un patient insuffisant respiratoire chronique ayant une cardiopathie associée, pour confirmer ou infirmer l'origine cardiogénique d'un œdème pulmonaire hypoxémiant, ou encore pour identifier une participation cardiaque à un échec de sevrage du respirateur. The evaluation of left ventricular (LV) filling pressures is crucial to identify a congestive heart failure in a patient presenting with an acute respiratory failure. This evaluation traditionally relies on the invasive measurement of the pulmonary artery occlusion pressure during right heart catheterization. Echocardiography Doppler is an unparalleled alternative technique to assess LV filling pressures, which also provides anatomical and functional information on the heart and great vessels. Pulsed wave Doppler of the mitral valve and pulmonary veins provides indices that are easy to measure and allow a semi-quantitative assessment of LV filling pressures. Their accuracy increases in the presence of a LV systolic dysfunction. New Doppler indices, which assess more specifically LV diastolic properties (Doppler Tissue Imaging of the mitral ring, color M-mode propagation velocity) can be combined to traditional Doppler parameters to more precisely assess LV filling pressures. In addition, echocardiography allows a comprehensive assessment of both the left and right ventricular function, the diagnosis of an underlying cardiopathy, or the identification of an acute condition of the heart or great vessels that precipitated the acute respiratory failure. Accordingly, echocardiography Doppler is a cornerstone in the evaluation of patients presenting to the intensive care unit with a respiratory failure and a high index of suspicion of pulmonary venous congestion. This imaging modality is particularly valuable for the evaluation of patients with a medical history of chronic respiratory failure and cardiac failure, to confirm or confidently rule out a cardiogenic pulmonary edema, or to identify a cardiac source of ventilator weaning failure.
ABSTRACT Study hypothesis : Implementation of a new pathway dedicated to septic patients within the emergency department (ED) would improve early management, organ dysfunction, and outcome. Methods: During phase 1, all consecutive adult patients with infection and qualifying quick Sequential Organ Failure Assessment (qSOFA) score upon ED admission were managed according to standards of care. A multifaceted intervention was then performed (implementation phase): educational program, creation of a sepsis alert upon ED admission incorporated in the professional software, together with severity scores and Surviving Sepsis Campaign (SSC) bundle reminders, and dedication of two rooms to the management of septic patients (sepsis unit). During phase 2, patients were managed according to this new organization. Results: Of the 89,040 patients admitted to the ED over the two phases, 2,643 patients (3.2%) had sepsis including 277 with a qualifying qSOFA score on admission (phase 1, 141 patients; phase 2, 136 patients). Recommendations of SSC 3-h bundle significantly improved between the two periods regarding lactate measurement (87% vs. 96%, P = 0.006), initiation of fluid resuscitation (36% vs. 65%, P < 0.001), blood cultures sampling (83% vs. 93%, P = 0.014), and administration of antibiotics (18% vs. 46%, P < 0.001). The Sequential Organ Failure Assessment score between H0 and H12 varied significantly more during phase 2 (1.9 ± 1.9 vs. 0.8 ± 2.6, P < 0.001). Mortality significantly decreased during the second phase, on day 3 (28% vs. 15%, P = 0.008) and on day 28 (40% vs. 28%, P = 0.013). Conclusion: Systematic detection, education, and per protocol organization with a sepsis unit dedicated to the early management of septic patients appear to improve compliance with SSC bundles, organ dysfunction, and short-term mortality. These results warrant to be confirmed by prospective studies.
Abstract Introduction Conventional pulsed wave Doppler parameters are known to be preload dependent, whereas newly proposed Doppler indices may be less influenced by variations in loading conditions. The aim of the present study was to evaluate the effects of haemodialysis-induced preload reduction on both conventional and new Doppler parameters for the assessment of left ventricular (LV) diastolic function. Methods This prospective observational study was conducted in a medical-surgical intensive care unit (ICU) and nephrology department of a teaching hospital. In total, 37 haemodialysis patients with end-stage renal disease (age [mean ± standard deviation]: 52 ± 13 years) and eight ventilated ICU patients with acute renal failure receiving vasopressor therapy (age 57 ± 16 years; Simplified Acute Physiology Score II 51 ± 17) were studied. Echocardiography was performed before and after haemodialysis. Conventional pulsed wave Doppler indices of LV diastolic function as well as new Doppler indices, including Doppler tissue imaging early diastolic velocities (E' wave) of the septal and lateral portions of the mitral annulus, and propagation velocity of LV inflow at early diastole (Vp) were measured and compared before and after ultrafiltration. Results The volume of ultrafiltration was greater in haemodialysis patients than in ICU patients (3.0 ± 1.1 l versus 1.9 ± 0.9 l; P = 0.005). All conventional pulsed wave Doppler parameters were altered by haemodialysis. In haemodialysis patients, E' velocity decreased after ultrafiltration when measured at the septal mitral annulus (7.1 ± 2.5 cm/s versus 5.9 ± 1.7 cm/s; P = 0.0003), but not at its lateral portion (8.9 ± 3.1 cm/s versus 8.3 ± 2.6 cm/s; P = 0.37), whereas no significant variation was observed in ICU patients. Vp decreased uniformly after ultrafiltration, the difference being significant only in haemodialysis patients (45 ± 11 cm/s versus 41 ± 13 cm/s; P = 0.04). Although of less magnitude, ultrafiltration-induced variations in Doppler parameters were also observed in haemodialysis patients with altered LV systolic function. Conclusion In contrast to other Doppler parameters, Doppler tissue imaging E' maximal velocity measured at the lateral mitral annulus represents an index of LV diastolic function that is relatively insensitive to abrupt and marked preload reduction.
Abstract Background Critically ill patients with obesity may have an increased risk of difficult intubation and subsequent severe hypoxemia. We hypothesized that pre-oxygenation with noninvasive ventilation before intubation as compared with high-flow nasal cannula oxygen may decrease the risk of severe hypoxemia in patients with obesity. Methods Post hoc subgroup analysis of critically ill patients with obesity (body mass index ≥ 30 kg·m −2 ) from a multicenter randomized controlled trial comparing preoxygenation with noninvasive ventilation and high-flow nasal oxygen before intubation of patients with acute hypoxemic respiratory failure (PaO 2 /FiO 2 < 300 mm Hg). The primary outcome was the occurrence of severe hypoxemia (pulse oximetry < 80%) during the intubation procedure. Results Among the 313 patients included in the original trial, 91 (29%) had obesity with a mean body mass index of 35 ± 5 kg·m −2 . Patients with obesity were more likely to experience an episode of severe hypoxemia during intubation procedure than patients without obesity: 34% (31/91) vs. 22% (49/222); difference, 12%; 95% CI 1 to 23%; P = 0.03. Among patients with obesity, 40 received preoxygenation with noninvasive ventilation and 51 with high-flow nasal oxygen. Severe hypoxemia occurred in 15 patients (37%) with noninvasive ventilation and 16 patients (31%) with high-flow nasal oxygen (difference, 6%; 95% CI − 13 to 25%; P = 0.54). The lowest pulse oximetry values during intubation procedure were 87% [interquartile range, 77–93] with noninvasive ventilation and 86% [78–92] with high-flow nasal oxygen ( P = 0.98). After multivariable analysis, factors independently associated with severe hypoxemia in patients with obesity were intubation difficulty scale > 5 points and respiratory primary failure as reason for admission. Conclusions Patients with obesity and acute hypoxemic respiratory failure had an increased risk of severe hypoxemia during intubation procedure as compared to patients without obesity. However, preoxygenation with noninvasive ventilation may not reduce this risk compared with high-flow nasal oxygen. Trial registration Clinical trial number: NCT02668458 ( http://www.clinicaltrials.gov )
