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P Vignon

Publications and source records attributed to P Vignon.

At least 37 records · Page 2Linked to original sources
PubMed1998

Traumatic pulmonary hernia: surgical versus conservative management.

The therapeutic management of lung herniation, an uncommon complication of severe blunt chest trauma, remains controversial. We report here on two cases of traumatic lung herniation with different, yet successful, methods of therapeutic management according to the particular anatomic types. Because of the threat of tension pneumothorax, incarceration, or strangulation of the lung parenchyma in mechanically ventilated patients, surgical reduction of intercostal pulmonary hernias with narrow necks is usually recommended. In contrast, supraclavicular pulmonary hernias secondary to clavicle-sternal dislocation may be treated conservatively with serial clinical and thoracic imaging follow-up including chest computed tomographic scan. In this anatomical type of lung herniation, favorable spontaneous evolution is frequently observed, presumably because of the presence of a larger thoracic wall defect together with the absence of associated perforating bone trauma. The efficacy of the therapeutic approach proposed herein remains to be confirmed by further experience.

Adult↗
PubMed1998

Quantification of traumatic hemomediastinum using transesophageal echocardiography: impact on patient management.

STUDY OBJECTIVES: To determine whether the quantitative evaluation of hemomediastinum using transesophageal echocardiography (TEE) is predictive of the presence of a traumatic disruption of the thoracic aorta (TDA) or its branches in patients who have sustained severe blunt chest trauma. DESIGN: Retrospective study. SETTING: ICU of a tertiary referral teaching hospital. PATIENTS: Forty-one patients sustaining severe blunt chest trauma (32 men, nine women; mean age, 43+/-16 years; mean Injury Severity Score, 39+/-22) who underwent a TEE study were divided into two groups, patients with (group TDA+, n=15) or without (group TDA-, n=26) major vascular injury diagnosed using an alternative method such as aortography, surgery, or necropsy. The control group included 41 age- and sex-matched patients with an unremarkable TEE study performed to rule out an intracardiac source of emboli. INTERVENTIONS: The presence of hemomediastinum was quantitatively assessed by measuring the distances between the esophageal scope and anteromedial aortic wall (distance 1), and between the posterolateral aortic wall and left visceral pleura (distance 2) at the level of the aortic isthmus. An observer who was unaware of both medical history and final diagnosis measured the distances. MEASUREMENTS AND RESULTS: In group TDA+, TEE demonstrated aortic injuries in 13 patients, revealed an isolated hemomediastinum in one patient (ruptured intercostal arteries), and was unremarkable in the remaining patient, who sustained a disrupted right subclavian artery. No associated major vessel injuries were diagnosed in the group TDA- (normal aortograms). When compared to the control group, mean distances were greater in patients with chest trauma (distance 1=5.5+/-4.4 mm vs 2.7+/-0.8 mm, p=0.001; distance 2=3.8+/-5.0 mm vs 1.2+/-0.3 mm, p=0.02). The corresponding distances were even greater in group TDA+ when compared with group TDA- (distance 1=8.6+/-5.9 mm vs 3.7+/-1.5 mm, and distance 2=7.1+/-7.0 mm vs 2.0+/-1.7; for both differences, p<0.01). A threshold value of 5.5 mm for distance 1 or 6.6 mm for distance 2 had a sensitivity of 80%, a specificity of 92%, a positive and negative predictive value of 86% and 89%, respectively, for the diagnosis of underlying major vascular injury. CONCLUSIONS: TEE allows quantitative assessment of traumatic hemomediastinum. The presence of a large hemomediastinum requires further evaluation by aortography, even if the thoracic aorta appears normal during the TEE examination, in order to rule out an underlying major vascular injury which may be outside the field of view of the echocardiographer.

Adolescent↗
PubMed1997

[Continuous intrathecal injection of baclofen in generalized tetanus. A therapeutic alternative].

BACKGROUND: In France, tetanus is diagnosed predominantly in the elderly due to the absence of vaccination in this population. Mortality remains high and is mainly related to complications secondary to prolonged hospitalization, intravenous administration of benzodiazepines, and at times curares. Baclofen, a selective agonist of GABAB receptors, directly counteracts the effects of the tetanic toxin. CASE REPORT: We report the case of a 92-year-old man suffering from tetanus, who fully recovered after a myorelaxant treatment based solely on intrathecal baclofen administration. Continuous intrathecal administration of baclofen resulted in a marked muscular relaxation with minor side effects (bradycardia, sleepiness), which rapidly stopped after the cessation of the treatment. Initial careful titration is required in order to determine the optimal dose of baclofen which provides a substantial myorelaxation together with minor central effects. Low concentration of baclofen may facilitate its diffusion. DISCUSSION: Continuous intrathecal administration of barclofen appears to be a valuable alternative therapy in tetanus. This new therapeutic modality promises to improve the prognosis of this condition, especially in the elderly.

Aged↗
PubMed1997

Segmental analysis of color kinesis images: new method for quantification of the magnitude and timing of endocardial motion during left ventricular systole and diastole.

BACKGROUND: We describe a method for objective assessment of left ventricular (LV) endocardial wall motion based on Color Kinesis, a new echocardiographic technique that color-encodes pixel transitions between blood and myocardial tissue. METHODS AND RESULTS: We developed a software that analyzes Color Kinesis images and provides quantitative indices of magnitude and timing of regional endocardial motion. Images obtained in 12 normal subjects were used to evaluate the variability in each index. Esmolol, dobutamine, and atropine were used to track variations in LV function in 14 subjects. Objective evaluation of wall motion was tested in 20 patients undergoing dobutamine stress testing. Regional fractional area change, displacement, and radial shortening were displayed as histograms and time curves. Global function was assessed by calculating magnitude and timing of peak ejection or filling rates and mean time of ejection or filling. Patterns of endocardial motion were consistent between normal subjects. Fractional area change and peak ejection rate decreased with esmolol and increased with dobutamine. Time to peak ejection and mean time of contraction were prolonged with esmolol and shortened with dobutamine. Using atropine, we proved that our findings with dobutamine were not secondary to its chronotropic effects. Dobutamine induced regional wall motion abnormalities in 10 patients in 38 segments diagnosed conventionally. Segmental analysis detected abnormalities in 36 of these 38 segments and in an additional 5 of 322 segments. CONCLUSIONS: Analysis of Color Kinesis images allows fast, objective, and automated evaluation of regional wall motion sensitively enough to evaluate clinical dobutamine stress data. This method has significant potential in the diagnosis of myocardial ischemia.

Adrenergic beta-Agonists↗
PubMed1997

Thrombocytopenia in the sepsis syndrome: role of hemophagocytosis and macrophage colony-stimulating factor.

BACKGROUND: Thrombocytopenia is frequently encountered in critically ill patients with the sepsis syndrome, but its mechanisms frequently remain undetermined. Hemophagocytosis has been reported as a cause of thrombocytopenia in various diseases. This prospective study was designed to assess: (1) the incidence of hemophagocytosis in patients suffering from both the sepsis syndrome and unexplained thrombocytopenia, and (2) the circulating level of the macrophage-colony-stimulating factor (M-CSF) according to the presence or absence of hemophagocytosis. METHODS: Fifty consecutive patients diagnosed with both the sepsis syndrome and thrombocytopenia of undetermined origin were studied. Hemophagocytosis was diagnosed based on microscopical examination of sternal bone marrow aspiration by two independent observers. Serum M-CSF concentrations were measured in each patient and compared with levels of a normal population (n = 59). Causes and severity of sepsis syndromes as well as serum M-CSF levels were compared between patients with and without hemophagocytosis. RESULTS: Hemophagocytosis was diagnosed in 32 patients (64%). Mean serum M-CSF levels were increased in patients when compared with normal subjects (539 +/- 141 versus 208 +/- 82 IU/mL: P < 0.001), and higher in patients with than without hemophagocytosis (580 +/- 145 versus 457 +/- 89 IU/mL: P = 0.01). Multiorgan dysfunction and infection were independent risk factors of hemophagocytosis (odds ratio = 31.3 and 6.8, 95% confidence interval (CI) = 5.4 to 177.6 and 1.0 to 47.4, P <0.0001 and P = 0.03, respectively). CONCLUSIONS: Hemophagocytosis is a frequent cause of unexplained thrombocytopenia in patients with severe sepsis syndrome. Our results suggest that M-CSF is overproduced in the sepsis syndrome, particularly when hemophagocytosis is present. The role of M-CSF in the initiation and development of hemophagocytosis remains to be determined.

Adult↗
PubMed1997

Transnasal transesophageal echocardiography.

Transesophageal echocardiography has been used as a diagnostic tool in the critical care unit. However, long-term serial evaluation of ventricular function with transesophageal echocardiography is difficult because of the current probe sizes and intolerance to prolonged oral intubation. We performed 139 intubations (64 oral and 75 transnasal) with a new prototype probe in 128 patients referred for transesophageal echocardiography. Transnasal intubation with the prototype probe was possible in 63/75 attempts. Oral intubation was successful in all 64 attempts. Patients tolerated transnasal intubation well when mildly sedated or awake. Two-dimensional echocardiographic views obtained with the nasal probe were similar to those obtained with a standard monoplane probe. Image quality was rated as good or acceptable in nearly all cases. Transgastric short-axis imaging of the left ventricle combined with acoustic quantification provided stable left ventricular area waveforms. Using custom developed software we showed the feasibility of monitoring left ventricular performance with minimal probe adjustment while graphically displaying and updating left ventricular area and fractional area change. Thus, transesophageal echocardiography with a prototype miniaturized monoplane probe passed transnasally is feasible, safe, and well tolerated by patients. This probe provides excellent two-dimensional echocardiographic images and may allow long-term echocardiographic monitoring of ventricular performance.

Adult↗
PubMed1996

Echocardiographic quantification of regional left ventricular wall motion with color kinesis.

BACKGROUND: Color kinesis is a new technology for the echocardiographic assessment of left ventricular wall motion based on acoustic quantification. This technique automatically detects endocardial motion in real time by using integrated backscatter data to identify pixel transitions from blood to tissue during systole on a frame-by-frame basis. In this study, we evaluated the feasibility and accuracy of quantitative segmental analysis of color kinesis images to provide objective evaluation of regional systolic endocardial motion. METHODS AND RESULTS: Two-dimensional echocardiograms were obtained in the short-axis and apical four-chamber views in 20 normal subjects and 40 patients with regional wall motion abnormalities. End-systolic color overlays superimposed on the gray scale images were obtained with color kinesis to color encode left ventricular endocardial motion throughout systole on a frame-by-frame basis. These color-encoded images were divided into segments by use of custom software. In each segment, pixels of different colors were counted and displayed as stacked histograms reflecting the magnitude and timing of regional endocardial excursion. In normal subjects, histograms were found to be highly consistent and reproducible. The patterns of contraction obtained in normal subjects were used as a reference for the objective automated interpretation of regional wall motion abnormalities, defined as deviations from this pattern. The variability in the echocardiographic interpretation of wall motion between two experienced readers was similar to the diagnostic variability between the consensus of the two readers and the automated interpretation. CONCLUSIONS: Color kinesis is a promising new tool that may be used clinically to improve the qualitative and quantitative evaluation of spatial and temporal aspects of global and regional wall motion. In this initial study, segmental analysis of color kinesis images provided accurate, automated, and quantitative diagnosis of regional wall motion abnormalities.

Adult↗
PubMed1996

Feasibility of aortic diameter measurement by multiplane transesophageal echocardiography for preoperative selection and preparation of homograft aortic valves.

BACKGROUND: Preoperative knowledge of the aortic annular diameter could enable the preoperative selection and preparation of an appropriately sized homograft aortic valve. OBJECTIVE: The aims of this study were to prospectively determine whether the combined use of transthoracic and multiplane transesophageal echocardiography allows accurate preoperative aortic annular measurements for the selection and preparation of adequately sized homograft aortic valves and to retrospectively evaluate the influence of the echocardiographic approach (transthoracic vs transesophageal) and the reader's level of experience on the accuracy of these measurements. METHODS: Aortic annular measurements were performed before the operation by an experienced reader who used a combination of transthoracic and multiplane transesophageal images of 25 patients (mean age 52 +/- 13 years) referred for homograft aortic valve replacement. Measurements were also performed retrospectively by three additional readers with different levels of training in echocardiography. These readers acquired aortic annular diameters from prerecorded tapes and obtained measurements from each echocardiographic modality independently. All values were compared with the surgical measurement obtained with a ring valve sizer. RESULTS: With the combined echocardiographic approach, excellent agreement was found between preoperative echocardiographic and surgical measurements (mean difference +/- 2 standard deviations = 0.2 +/- 1.4 mm). All echocardiographic data were found to be within 2 mm of the surgical measurement. These measurements were used to select and prepare the aortic homograft valve before insertion. The accuracy of annular measurements appeared to increase in parallel to the level of experience. The aortic annular measurements obtained retrospectively by a second experienced reader were more accurate with the use of transesophageal than with transthoracic echocardiography (p < 0.01). In contrast, the echocardiographic modality had no influence on the accuracy of measurements of less experienced readers (p > 0.2). CONCLUSIONS: Preoperative measurement of the aortic annular diameter by transthoracic and multiplane transesophageal echocardiography is accurate and clinically feasible. Preoperative knowledge of the aortic annular diameter may be used to select and prepare the aortic homograft, improving valve availability and reducing ischemic time.

Adult↗
PubMed1996

Routine transesophageal echocardiography for the diagnosis of aortic disruption in trauma patients without enlarged mediastinum.

OBJECTIVE: To assess the value of routine transesophageal echocardiography (TEE) in diagnosing traumatic disruption of the aorta (TDA) in trauma patients presenting without enlarged mediastinum on chest x-ray films. DESIGN: Prospective study. MATERIALS AND METHODS: TEE was routinely performed to exclude the presence of TDA in patients who sustained severe trauma secondary to abrupt deceleration collisions and presented with an upper mediastinum of fewer than 8 cm on supine chest x-ray films. Patients were divided into two groups according to the presence (group I) or absence (group II) of mediastinal hematoma diagnosed during TEE examination. Radiographic signs regarded as indicators of the presence of TDA were evaluated in both groups. RESULTS: Among the 40 consecutive patients studied, TEE demonstrated two cases of TDA associated with a mediastinal hematoma that were confirmed by both aortography and surgery. One of the patients had a normal mediastinum on presentation chest x-ray films, and the other only exhibited a blurred aortic knob. Radiographic mediastinal abnormalities suggestive of TDA were observed in 13 patients, but chest x-ray films were unremarkable in 12 patients. Twenty patients had multiple rib fractures. The frequency of chest radiographic abnormalities was not significantly higher in group I (n = 6) when compared with group II patients (n = 34). TEE examination demonstrated a normal thoracic aorta in 35 patients and was nondiagnostic in 3 patients (normal aortography). CONCLUSION: TEE should be routinely performed in victims of violent deceleration collisions, even in patients presenting apparently normal mediastinum on supine chest radiography.

Accidents, Traffic↗
PubMed1995

Role of transesophageal echocardiography in the diagnosis and management of traumatic aortic disruption.

BACKGROUND: Traumatic disruption of the aorta (TDA) is a life-threatening injury that requires rapid diagnosis and treatment. Emergency aortography, which is the current standard diagnostic imaging modality, is invasive, time-consuming, and difficult to perform in hemodynamically unstable patients with multiple trauma. We performed transesophageal echocardiography (TEE) in patients with suspected TDA to determine the diagnostic accuracy and impact on patient management of this alternative, portable imaging modality. METHODS AND RESULTS: Thirty-two consecutive trauma patients (mean age, 40 +/- 16 years) with suspected TDA (violent deceleration accident and mediastinum > 8 cm on admission chest x-ray) prospectively underwent a TEE examination in the emergency room. Findings during TEE were compared with those encountered during aortography, surgery, or necropsy. Two subsets of traumatic aortic injuries with distinct echocardiographic signs were observed: (1) subadventitial TDA (n = 10) and (2) traumatic intimal tears (n = 3). Eighteen patients had normal TEE confirmed by aortography. One 2-mm medial tear was missed by TEE (necropsy). The sensitivity and specificity of TEE for the diagnosis of subadventitial TDA were 91% and 100%, respectively. Patients with subadventitial TDA were taken to surgery immediately, whereas patients with intimal aortic tears were treated conservatively. Eighteen patients (mean age, 57 +/- 15 years) with confirmed acute aortic dissection involving the aortic isthmus were also included to establish the echocardiographic differential diagnostic criteria between this entity and TDA. CONCLUSIONS: TEE should be considered the first-line imaging modality for the evaluation of trauma patients with suspected injuries of the thoracic aorta because of its portability, safety, diagnostic accuracy, and potential impact on patient management.

Adult↗
PubMed1995

Transesophageal echocardiography for the diagnosis and management of nonobstructive thrombosis of mechanical mitral valve prosthesis.

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 to 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 (> or = 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.

Adult↗
PubMed1995

[Reactive hemophagocytic syndrome: a probably underestimated cause of thrombocytopenia in intensive acre patients].

Thrombocytopenia is a common feature in ICU patients which occurs usually in case of infection or septic shock. Its mechanisms, which are often unclear, include the haemophagocytic syndrome initially linked with histiocytic proliferation but probably also associated with infectious diseases. This syndrome is characterized by a phagocytosis of medullar blood cells. Reactive haemophagocytic syndrome can probably lead to thrombocytopenia in ICU patients as in this case report of a E. Coli infection.

Aged↗
PubMed1995

Frequency of bacteremia associated with transesophageal echocardiography in intensive care unit patients: a prospective study of 139 patients.

OBJECTIVE: To determine the occurrence rate of bacteremia associated with transesophageal echocardiography in intensive care unit (ICU) patients. DESIGN: A prospective study of 139 patients undergoing transesophageal echocardiography. SETTING: The medical ICU of a tertiary referral teaching hospital. PATIENTS: One hundred thirty-nine ICU patients (mean age 58 yrs) who underwent transesophageal echocardiography. INTERVENTIONS: Blood samples were systematically drawn for aerobic and anaerobic culture at the following times: before (blood culture 1), at the end of (blood culture 2), and 30 mins after (blood culture 3) transesophageal echocardiography examinations. MEASUREMENTS AND MAIN RESULTS: The mean duration of transesophageal echocardiography was 35 mins (range 7 to 120). One hundred thirty-four patients received mechanical ventilation; 125 patients had a nasogastric tube. Fifty-one patients had one or more underlying conditions that usually justify antimicrobial prophylaxis of bacterial endocarditis before high-risk procedures. Fifty-six patients did not receive any antibiotic treatment at the time of transesophageal echocardiography. In 114 patients, the three blood cultures were negative. In six patients, transesophageal echocardiography was performed during a preexisting bacteremia. A contamination (only one positive blood culture of the three sampling times) with coagulase-negative staphylococci occurred in four patients at blood culture 1, five patients at blood culture 2, and six patients at blood culture 3. Contamination with Corynebacterium species occurred in two patients at blood culture 2. In one patient receiving cefotaxime and netilmicin, blood culture 1 was sterile and blood cultures 2 and 3 yielded coagulase-negative staphylococci. In one patient receiving no antibiotic treatment, blood culture 1 was sterile and blood cultures 2 and 3 yielded Enterococcus faecalis. None of these two patients received a specific antibiotic treatment or developed any secondary septic focus. CONCLUSIONS: The overall frequency of bacteremia induced by transesophageal echocardiography in ICU patients was 1.4% (two of 139 patients) (95% confidence interval 0.2% to 5.1%). The frequency did not differ whether patients received antibiotics before transesophageal echocardiography (one [1.2%] of 83 patients) or not (one [1.8%] of 56 patients) (p = .96). Therefore, routine antimicrobial prophylaxis does not appear justified before transesophageal echocardiography in ICU patients.

Adult↗