Philippe Revel

Evaluation of a new pocket echoscopic device for focused cardiac ultrasonography in an emergency setting

IntroductionIn the emergency setting, focused cardiac ultrasound has become a fundamental tool for diagnostic, initial emergency treatment and triage decisions. A new ultra-miniaturized pocket ultrasound device (PUD) may be suited to this specific setting. Therefore, we aimed to compare the diagnostic ability of an ultra-miniaturized ultrasound device (Vscan™, GE Healthcare, Wauwatosa, WI) and of a conventional high-quality echocardiography system (Vivid S5™, GE Healthcare) for a cardiac focused ultrasonography in patients admitted to the emergency department.MethodsDuring 4 months, patients admitted to our emergency department and requiring transthoracic echocardiography (TTE) were included in this single-center, prospective and observational study. Patients underwent TTE using a PUD and a conventional echocardiography system. Each examination was performed independently by a physician experienced in echocardiography, unaware of the results found by the alternative device. During the focused cardiac echocardiography, the following parameters were assessed: global cardiac systolic function, identification of ventricular enlargement or hypertrophy, assessment for pericardial effusion and estimation of the size and the respiratory changes of the inferior vena cava (IVC) diameter.ResultsOne hundred fifty-one (151) patients were analyzed. With the tested PUD, the image quality was sufficient to perform focused cardiac ultrasonography in all patients. Examination using PUD adequately qualified with a very good agreement global left ventricular systolic dysfunction (κ = 0.87; 95%CI: 0.76-0.97), severe right ventricular dilation (κ = 0.87; 95%CI: 0.71-1.00), inferior vena cava dilation (κ = 0.90; 95%CI: 0.80-1.00), respiratory-induced variations in inferior vena cava size in spontaneous breathing (κ = 0.84; 95%CI: 0.71-0.98), pericardial effusion (κ = 0.75; 95%CI: 0.55-0.95) and compressive pericardial effusion (κ = 1.00; 95%CI: 1.00-1.00).ConclusionsIn an emergency setting, this new ultraportable echoscope (PUD) was reliable for the real-time detection of focused cardiac abnormalities.

Noninvasive assessment of macrovesicular liver steatosis in cadaveric donors based on computed tomography liver-to-spleen attenuation ratio

Fatty liver disease, including liver steatosis, is a major health problem worldwide. In liver transplantation, macrovesicular steatosis in donor livers is a major cause of graft failure and remains difficult to assess. On one hand, several imaging modalities can be used for the assessment of liver fat, but liver biopsy, which is still considered the gold standard, may be difficult to perform in this context. On the other hand, computed tomography (CT) is commonly used by teams managing cadaveric donors to assess donors and to minimize the risk of complications in recipients. The purpose of our study was to validate the use of CT as a semiquantitative method for assessing macrovesicular steatosis in cadaveric donors with liver biopsy as a reference standard. A total of 109 consecutive cadaveric donors were included between October 2009 and May 2011. Brain death was diagnosed according to French legislation. Liver biopsy and then CT were performed on the same day to determine the degree of macrovesicular steatosis. All liver biopsies and CT scans were analyzed in a double‐blinded fashion by a senior pathologist and a senior radiologist, respectively. For CT, we used the liver‐to‐spleen (L/S) attenuation ratio, which is a validated method for determining 30% or greater steatosis in living liver donors. Fourteen of 109 biopsies exhibited macrovesicular steatosis > 30% upon histologic analysis. A receiver operating characteristic curve was generated for the L/S ratio to identify its ability to predict significant steatosis, which was defined as >30%. A cutoff value of 0.9 for the CT L/S ratio provided a sensitivity of 79% and a specificity of 97% to detect significant steatosis. Liver Transpl 21:690‐695, 2015.

Benefits of intravenous lidocaine on post-operative pain and acute rehabilitation after laparoscopic nephrectomy

Background and Aims: Intravenous (I.V.) lidocaine has analgesic, antihyperalgesic and anti-inflammatory properties and is known to accelerate the return of bowel function after surgery. We evaluated the effects of I.V. lidocaine on pain management and acute rehabilitation protocol after laparoscopic nephrectomy. Materials and Methods: A total of 47 patients scheduled to undergo laparoscopic nephrectomy were included in a two-phase observational study where I.V. lidocaine (1.5 mg/kg/h) was introduced, in the second phase, during surgery and for 24 h post-operatively. All patients underwent the same post-operative rehabilitation program. Post-operative pain scores, opioid consumption and extent of hyperalgesia were measured. Time to first flatus and 6 min walking test (6MWT) were recorded. Results: Patient demographics were similar in the two phases (n = 22 in each group). Lidocaine significantly reduced morphine consumption (median [25-75% interquartile range]; 8.5 mg[4567891011121314151617] vs. 25 mg[1920212223242526272829303132]; P < 0.0001), post-operative pain scores (P < 0.05) and hyperalgesia extent on post-operative day 1-day 2-day 4 (mean ± standard deviation (SD); 1.5 ± 0.9 vs. 4.3 ± 1.2 cm (P < 0.001), 0.6 ± 0.5 vs. 2.8 ± 1.2 cm (P < 0.001) and 0.13 ± 0.3 vs. 1.2 ± 1 cm (P < 0.001), respectively). Time to first flatus (mean ± SD; 29 ± 7 h vs. 48 ± 15 h; P < 0.001) and 6MWT at day 4 (189 ± 50 m vs. 151 ± 53 m; P < 0.001) were significantly enhanced in patients with i.v. lidocaine. Conclusion: Intravenous (I.V.) lidocaine could reduce post-operative morphine consumption and improve post-operative pain management and post-operative recovery after laparoscopic nephrectomy. I.V. lidocaine could contribute to better post-operative rehabilitation.

Goal-directed ultrasound in emergency medicine: evaluation of a specific training program using an ultrasonic stethoscope.

Objective This observational study aimed to define the learning curve in goal-directed ultrasound (US) after a 2-day training course dedicated to novice emergency residents. Materials and methods After completion of the training program, 180 patients requiring goal-directed US examination were examined by a resident and by an experienced investigator. The main endpoints were the diagnostic agreement between the two operators for 14 clinical questions, the duration of the examinations, the number of nonaddressed questions, and the final diagnosis. All criteria were analyzed according to the experience of the resident every 10 examinations. Results After 30 supervised examinations, residents adequately assessed with a very good or considerable agreement global left ventricular systolic dysfunction [&kgr;=0.92; 95% confidence interval (CI): 0.80–1], severe right ventricular dilation (&kgr;=0.73; 95% CI: 0.37–1), inferior vena cava diameter (&kgr;=0.88; 95% CI: 0.71–1), and pericardial effusion (&kgr;=0.85; 95% CI: 0.55–1). In general US, 20 supervised examinations were required to diagnose intraperitoneal effusion (&kgr;=0.81; 95% CI: 0.61–1), cholelithiasis (&kgr;=0.73; 95% CI: 0.36–1), obstructive uropathy (&kgr;=0.85; 95% CI: 0.56–1), bladder distention (&kgr;=1; 95% CI: 1–1), abdominal aortic aneurism (&kgr;=0.9; 95% CI: 0.74–1), alveolar interstitial pattern (&kgr;=0.87; 95% CI: 0.74–0.99), consolidated lung (&kgr;=0.83; 95% CI: 0.68–0.97), or pleural effusion (&kgr;=0.89; 95% CI: 0.77–1). After 30 supervised examinations, the overall diagnostic accuracy was judged excellent between the two investigators, with a significant improvement during the learning curve. Conclusion The performance of 30 supervised and goal-oriented examinations appeared adapted to adequately answer clinical questions covered by core applications of emergency US.

Vital Capacity Impairment due to Neuromuscular Disease and its Correlation with Diaphragmatic Ultrasound: A Preliminary Study

The purpose of this pilot study was to evaluate the correlation between diaphragmatic excursion measured by a right sub-costal ultrasound approach and forced vital capacity in patients with amyotrophic lateral sclerosis (ALS) or myotonic dystrophy (MD). All patients referred for pulmonary function testing underwent ultrasonic measurement of diaphragmatic excursion during quiet breathing, voluntary sniffing (Esniff) and forced breathing (EDEmax). Forty-five patients were included, mainly for amyotrophic lateral sclerosis or myotonic dystrophy. There was a significant correlation between EDEmax values and forced vital capacity (FVC) values (r = 0.68 [0.46–0.90], p < 0.0001) and between EDEmax values and percentage of predicted FVC values (r = 0.75 [0.55–0.95], p < 0.0001). At a threshold of EDEmax < 5.5 cm, the sensitivity and specificity of ultrasonic diaphragmatic excursion in predicting FVC ≤ 50% of theoretical values were 100% [66%–100%] and 69% [52%–84%] respectively, without any significant difference between males and females. There was no statistical correlation between maximal inspiratory pressure and Esniff.

Noninvasive ventilation in blunt chest trauma: beware of missed esophageal injuries!

Dear Editor, For several years, there has been an exponential use of noninvasive ventilation (NIV) for the treatment or prevention of acute respiratory failure, while the actual benefit has not been fully documented for all applications [1–4]. In blunt chest trauma patients, early use of NIV has been shown to prevent intubation and decrease overall complications [4]. However, an inappropriate use in nonselected patients can raise the concern of potentially lethal complications due to initially missed aerodigestive injuries. Thus we report the case of a 26-year-old patient admitted in our trauma center after a blunt chest trauma due to high-speed motorvehicle accident. The whole body computed tomography (CT) scan revealed multiple ribs fractures and pulmonary contusions without sepsis or respiratory failure. Moderate mediastinal air was attributed to the fractures and/or lung trauma, as no obvious aerodigestive perforation was identified (Fig. 1a). The initial management consisted of effective pain control by epidural analgesia and early NIV to prevent secondary respiratory failure. After 48 hours of intensive care, the constitution of a pleural effusion and emergence of a septic shock motivated a second CT scan, which revealed an increase of pneumomediastinum due to a large esophageal perforation (Fig. 1b). The patient was then transferred for suture of esophageal perforation and effective pleural and mediastinal drainage. After treatment of the septic shock, a favourable outcome allowed discharge of the patient after 15 days of intensive care. To our knowledge, this is the first published report of esophageal perforation associated with an inappropriate use of NIV in blunt chest trauma patients. Traumatic esophageal perforation is an extremely rare event associated with an important morbidity and mortality [5]. For the diagnosis, the gold standard remains a water-soluble contrast swallow, but this investigation requires a cooperative patient. In ventilated patients, flexible esophagoscopy should be used. Thoracic CT-scan can also be a useful diagnostic modality when allowing direct visualization of esophageal disruption. However, subtle perforations may be missed, especially at the early stage. CT-scan often provides non-specific signs often ascribed to more common blunt thoracic injuries. Indeed, pneumomediastinum is not uncommon in the polytrauma patients, but has been found to have little clinical significance to predict aerodigestive tract injuries. Thus, it can be difficult to justify a systematic endoscopy in front of a pneumomediastinum in the absence of another argument for esophageal perforation in the initial phase of trauma. Consequently, delayed diagnosis of esophageal perforation is very frequent, reaching 50 % in some series [5]. Then, imaging examinations should be controlled in case of persistent diagnostic uncertainty or clinical worsening. Whatever the diagnosis strategy, it is necessary to avoid iatrogenic injury by improper increase in esophageal pressure, as the diagnosis of esophageal injury is not eliminated. In conclusion, this case emphasizes the need for vigilance in the detection of uncommon esophageal injuries when NIV should be indicated in blunt chest trauma patients. Thus, when CT scan cannot rule out traumatic esophageal injury, NIV should be delayed to perform systematic evaluation with more specific esophageal imaging within 12–24 h.

An ex vivo original test using radiotracers for evaluating haemocompatibility of tubular biomaterials

The haemocompatibility of a vascular prosthesis can be estimated as the result of its interaction with blood components. The authors describe an ex vivo canine shunt for evaluating isotopic haemocompatibility in blood-wall interactions. Methods employing radioisotopic tracers can be used to dynamically monitor the adsorption of labelled blood cells and proteins on different biomaterial surfaces. This ex vivo test should enable materials to be assessed for quality according to two thrombogenic criteria: (i) number of adhered platelets mm-2 s-1; (ii) quantity of adsorbed fibrinogen expressed as microgram mm-2 s-1, which would provide the basis for a scale of haemocompatibility.

Bundle of care for blunt chest trauma patients improves analgesia but increases rates of intensive care unit admission: A retrospective case-control study

INTRODUCTION This single-centre retrospective case-control study aimed to assess the effectiveness of a multidisciplinary clinical pathway for blunt chest trauma patients admitted in emergency department (ED). PATIENTS AND METHODS All consecutive blunt chest trauma patients with more than 3 rib fractures and no indication of mechanical ventilation were compared to a retrospective cohort over two 24-month periods, before and after the introduction of the bundle of care. Improvement of analgesia was the main outcome investigated in this study. The secondary outcomes were the occurrence of secondary respiratory complications (pneumonia, indication for mechanical ventilation, secondary ICU admission for respiratory failure or death), the intensive care unit (ICU) and hospital length of stay (LOS). RESULTS Sixty-nine pairs of patients were matched using a 1:1 nearest neighbour algorithm adjusted on age and indices of severity. Between the two periods, there was a significant reduction of the rate of uncontrolled analgesia (55 vs. 17%, P<0.001). A significant increase in the rate of primary ICU transfer during the post-protocol period (23 vs. 52%, P<0.001) was not associated with a reduction of secondary respiratory complications or a reduction of ICU or hospital LOS. Only the use of non-steroidal anti-inflammatory drugs appeared to be associated with a significant reduction of secondary respiratory complications (OR=0.3 [0.1-0.9], P=0.03). CONCLUSION Implementation of a multidisciplinary clinical pathway significantly improves pain control after ED management, but increases the rate of primary ICU admission without significant reduction of secondary respiratory complications.

Ability of a new pocket echoscopic device to detect abdominal and pleural effusion in blunt trauma patients

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