Olivier Metton

Respiratory variations in pulse oximetry plethysmographic waveform amplitude to predict fluid responsiveness in the operating room.

Background:Respiratory variations in pulse oximetry plethysmographic waveform amplitude (&Dgr;POP) are related to respiratory variations in pulse pressure (&Dgr;PP) and are sensitive to changes in preload. The authors hypothesized that &Dgr;POP can predict fluid responsiveness in mechanically ventilated patients during general anesthesia. Methods:Twenty-five patients referred for cardiac surgery were studied after induction of general anesthesia. Hemodynamic data (cardiac index, central venous pressure, pulmonary capillary wedge pressure, &Dgr;PP, and &Dgr;POP) were recorded before and after volume expansion (500 ml hetastarch, 6%). Fluid responsiveness was defined as an increase in cardiac index of 15% or greater. Results:Volume expansion induced changes in cardiac index (2.0 ± 0.4 to 2.3 ± 0.5 mmHg; P < 0.05), &Dgr;PP (11 ± 7 to 6 ± 5%; P < 0.05), and &Dgr;POP (12 ± 9 to 7 ± 5%; P < 0.05). &Dgr;POP and &Dgr;PP were higher in responders than in nonresponders (17 ± 8 vs. 6 ± 4 and 14 ± 7 vs. 6 ± 4%, respectively; P < 0.05 for both). A &Dgr;POP greater than 13% before volume expansion allowed discrimination between responders and nonresponders with 80% sensitivity and 90% specificity. There was a significant relation between &Dgr;POP before volume expansion and percent change in cardiac index after volume expansion (r = 0.62; P < 0.05). Conclusions:&Dgr;POP can predict fluid responsiveness noninvasively in mechanically ventilated patients during general anesthesia. This index has potential clinical applications.

Anomalous origin of the left coronary artery from the pulmonary artery: late results with special attention to the mitral valve §

OBJECTIVE Evaluate the late results of a uniform approach to the surgical management of children with anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA). METHODS Between 1986 and 2007, 62 children with ALCAPA underwent surgery. The median age at operation was 16 months (range 10 days to 11 years). A uniform approach was applied, including (1) immediate surgery as soon as the diagnosis was established, (2) direct aortic reimplantation of the anomalous artery, when technically feasible (61/62, 98%), and (3) no concomitant mitral valve surgery, regardless of the severity of mitral regurgitation (59/62, 95%). The mean follow-up was 9.7 years (range 3 months to 21 years) and was 98% complete. RESULTS There were six hospital deaths (9.7%). Left ventricular assistance was used in four patients; two died of related complications. The poor left ventricular ejection fraction was an incremental risk factor for early mortality (p = 0.043); severity of mitral regurgitation was not. There were two late deaths, yielding an actuarial survival rate of 86% at 15 years. Five patients underwent reoperation (mitral valve repair in three, coronary procedure in two); the actuarial freedom from reoperation was 89% at 15 years. Left ventricular function recovered in all survivors. In the 50 late survivors who did not undergo mitral surgery at initial operation, the severity of mitral regurgitation decreased in 58%, remained unchanged in 40% (of which 3 patients underwent reoperation for mitral valve repair) and worsened in 2%; at last follow-up, mitral regurgitation was absent or trivial in 42%, mild in 50%, moderate in 8% and severe in 0%. CONCLUSIONS (1) Early mortality is related to the severity of preoperative left ventricular dysfunction; it may be reduced by a careful use of postoperative cardiac support techniques. (2) Late results are satisfactory and left ventricular function always recovers. (3) Mitral regurgitation improves along with left ventricular function, but recovery may be incomplete and need reoperation. The data suggest that mitral valve surgery is probably not indicated at initial surgery, except in selected cases with a low potential of recovery (severe regurgitation with relatively well-preserved left ventricular function).

Intramural coronary arteries and outcome of neonatal arterial switch operation.

OBJECTIVE To evaluate the impact of coronary patterns with intramural arteries on the outcome of arterial switch operation (ASO) in neonates with transposition of the great arteries (TGA). METHODS Between 1987 and 2008, 919 neonates underwent ASO for TGA. Forty-six (5.0%) had intramural coronary arteries. Intramural course involved the left main coronary artery in 28 of the 46 cases (61%), the left anterior descending artery in 12 patients (26%), the right coronary artery in three and both right and left coronary arteries in three cases. Various techniques were used to manage the coronary arteries: ASO without coronary relocation in one, ASO with coronary transfer as a single coronary button in nine and ASO with coronary transfer as two separate buttons in 36 patients (additional pericardial patches were implanted to orientate the coronary button in nine cases or enlarge the coronary ostium in three cases). The intramural course was unroofed in most cases (after 1995). RESULTS There were 13 deaths (28%): two intra-operative, nine before discharge from the hospital and two after discharge; during the same period, overall mortality in the 873 neonates with other coronary patterns was 3.9%. Actuarial survival at 10 years was 71 + or - 7%. Most deaths (11/13, i.e., 85%) were related to coronary complications. No time-trend effect was noted regarding mortality. Non-fatal coronary lesions were detected in eight patients (three with clinical evidence of myocardial infarction and five without). Five patients underwent re-operation for coronary revascularisation. Actuarial freedom from coronary events at 10 years was 46 + or - 10%. After a mean follow-up of 8.3 + or - 4.8 years, left ventricular function was normal in 97% of the survivors; minor ischaemic sequelae were present in two patients. CONCLUSIONS Coronary patterns with intramural arteries remain associated with high coronary mortality and morbidity following neonatal ASO, even in the current era. The association of slit-like deformation of the ostium, stenosis of the intramural course and abnormal angle of take-off might explain the difficulty in coronary transfer. The technique of coronary transfer should be individually adapted to each anatomical situation. The place of patch ostioplasty of the intramural artery remains to be determined.

Early prophylactic pulmonary artery banding in isolated congenitally corrected transposition of the great arteries

OBJECTIVE Mid-term evaluation of an aggressive surgical management of isolated congenitally corrected transposition of the great arteries (ccTGA) by pulmonary artery (PA) banding in early infancy. METHODS Between 2001 and 2009, 11 asymptomatic patients (seven neonates and four infants) underwent a dilatable, partially adjustable, homemade PA banding for ccTGA with intact ventricular septum. PA band circumference was correlated to body weight (22 mm+1 mm kg(-1)) and ideally adjusted to obtain flat septal geometry. Mean age at operation was 1.5±1.4 months. RESULTS There was no hospital mortality. Mean ventilation time and intensive care unit (ICU) stay were 20±9 h and 2.6±1.5 days, respectively. Five patients required postoperative inotropic support. One late death occurred suddenly at 4 months; normal biventricular function and no tricuspid regurgitation were noted at last follow-up, 1 week before death. Mean follow-up was 21.5±26 months. Mean band velocity increased over time from 2.65±0.7 m s(-1) postoperatively to 3.7±0.3 at 6 months and 4.5±0.4 m s(-1) at 2 years. Tricuspid regurgitation remained stable in seven patients, decreased in three and worsened in one. Flat septal geometry was obtained in all patients after the third postoperative month. One patient underwent a double-switch procedure at 7 years due to suprasystemic morphologically left ventricular pressure. The postoperative course was uneventful. CONCLUSIONS In neonates with isolated ccTGA, prophylactic PA banding is safe and carries a low morbidity. At mid-term evaluation, tricuspid valve function is stabilised or improved and systemic competence of the left ventricle is maintained, thus allowing double switch if indicated.

Common arterial trunk repair: with conduit or without?

OBJECTIVE To compare the mid-term results of two techniques used for the reconstruction of the pulmonary outflow tract during common arterial trunk repair in infancy, with special attention paid to re-operation rate and pulmonary arterial growth. METHODS Between 2000 and 2006, 32 consecutive neonates or infants underwent common arterial trunk repair. In 15 patients, the pulmonary outflow tract was reconstructed using an extracardiac valved conduit (conduit group). In 17 patients, right ventricle to pulmonary artery connection was achieved without conduit, using the left atrial appendage and including a monocusp valve (non-conduit group). The decision regarding the type of ventricle to pulmonary artery connection was at the discretion of the attending surgeon. The two groups were similar in terms of age, weight, type of common arterial trunk, truncal valve dysfunction and coronary abnormalities. Follow-up was 93% complete and included echo-Doppler evaluation, catheterisation and CT scan imaging. RESULTS Hospital mortality (five patients - 16%) was increased by coronary abnormalities and preoperative ventilation but did not differ between the two groups (13.3% in the conduit group vs 18% in the non-conduit group). The mean follow-up was 40+/-25 months. There were six late deaths (three in each group), yielding an actuarial survival of 76% at 5 years. One late death was procedure related (percutaneous dilatation for obstructive monocusp patch). Re-operation for right ventricular outflow tract obstruction was necessary in seven patients (five in the conduit group and two in the non-conduit group); the actuarial freedom from re-operation was higher in the non-conduit group (p=0.026). At last follow-up, the right ventricle-pulmonary artery gradient and the right ventricle/left ventricle pressure ratio were higher in the conduit group (p=0.006 and p=0.007, respectively). At late computed tomography (CT)-scan evaluation, the growth of the proximal pulmonary arterial tree had improved in the non-conduit group, as shown by a higher Nakata ostial index and right ventricular outflow tract growth. CONCLUSIONS Repair of common arterial trunk without conduit for right ventricular outflow tract reconstruction (1) does not increase mortality and morbidity, (2) decreases the need for re-intervention and (3) promotes a better growth of the proximal pulmonary arteries. These preliminary results need confirmation by further experience.

Surgical management of supravalvular aortic stenosis: does Brom three-patch technique provide superior results?

BACKGROUND Various surgical techniques have been proposed to repair supravalvular aortic stenosis. However, the optimal approach remains to be determined. The present study was undertaken to evaluate the results of surgery for supravalvular aortic stenosis and to compare the symmetric three-patch repair (Brom technique) with other surgical reconstructions. METHODS Between 1995 and 2007, 34 patients with supravalvular aortic stenosis underwent surgery. Fourteen patients (41%) had Williams syndrome. Supravalvular stenosis was discrete in 24 patients (71%) and diffuse in 10 (29%). Eight patients (23%) underwent one-patch repair; 3 patients (9%) had inverted bifurcated patch enlargement (Doty repair) and 23 patients (68%) had symmetric repair (Brom three-patch technique). Follow-up was complete and ranged from 6 months to 12 years (mean, 5.8 years). RESULTS There was one early and no late deaths. One patient (with one-patch repair) underwent reoperation for residual obstruction. At last follow-up, left ventricle to aorta peak gradient was 45 +/- 28 mm Hg after one-patch repair, 30 +/- 9 mm Hg after Doty operation, and 11 +/- 18 mm Hg after symmetric Brom procedure. Brom repair was associated with a low incidence of residual obstruction (peak gradient > or = 40 mm Hg) (2 of 22; 9.1%) and moderate aortic insufficiency (1 of 22; 4.5%). CONCLUSIONS Brom three-patch repair provides symmetric reconstruction of the aortic root in patients with supravalvular aortic stenosis. This may lead to improved midterm results in terms of relief of the obstruction and incidence of aortic insufficiency.

Intraoperative Transesophageal Echocardiography Using a Miniaturized Transducer in a Neonate Undergoing Norwood Procedure for Hypoplastic Left Heart Syndrome

A 7-day–old neonate (weight, 2.7 kg; height, 48 cm) with hypoplastic left heart syndrome was referred to our institution for a Norwood stage I palliation procedure. In the small neonate, conventional transesophageal echocardiographic probe insertion and manipulation can induce hemodynamic instability or respiratory compromise. Therefore, the usual weight range for neonates and infants who can be safely imaged in the operating department with the use of currently available echocardiographic probes is >3 kg. Recently, a …

A new surgical technique for transcatheter Fontan completion

OBJECTIVES Patients with complex congenital heart defects and univentricular heart usually required multiple palliative surgery aiming to separate pulmonary and systemic circulations. Various groups work on trying to perform the Fontan completion by a transcatheter technique. We developed and report here a modified technique to prepare the patient for this type of procedure. METHODS Sixteen sheep were included and prepared through a midline sternotomy. Preparation for transcatheter completion was performed using specially designed devices. The superior vena cava (SVC) was connected to the pulmonary artery (PA) using a Goretex conduit. The connection between the SVC and the right atrium (RA) was interrupted using a vascular stent occluded in the middle by a polytetrafluoroethylene (PTFE) membrane. Two nitinol rings were placed around the inferior vena cava (IVC). Immediately after preparation, the transcatheter completion was performed by first perforating the membrane of the occluded stent and by placing covered stents from IVC rings to the SVC stent. RESULTS Creation of the SVC to PA connection was uneventful. The insertion of the rings was done successfully in all animals very easily. All stents but one were completely occluding the SVC. Once, a tiny leak was noticed and successfully treated by additional stitches around the stent. Perforation of the membrane was done successfully in all animals re-establishing the pathway between the SVC and the RA. After dilatation of the stent, one animal required surgical control of a haemorrhage related to disruption of the SVC anastomosis. Three to four Cheatham-platinum (CP)-covered stents were necessary to complete the Fontan-like circulation. In the first animal, one stent moved downward missing its target. The placement between the two rings was easily performed using fluoroscopic guidance. No stents were positioned above the SVC stent keeping this part free of material. CONCLUSIONS We describe new improvements for surgical preparation for transcatheter completion of partial cavopulmonary connection. For superior connection, we developed an occluding stent that helps to re-establish RA to PA connection, alloys precise placement and enhances the stability of the completion stents. Inferiorly, anchorage of the covered stents is also improved by the use of nitinol rings.

SDRA infectieux réfractaire : place de l’oxygénation extracorporelle

Acute respiratory distress syndrome (ARDS) is a frequent cause of admission in intensive care unit. The treatment is well codified. Unfortunately some patients die because of hypoxemia despite a well-conducted medical treatment. Extracorporeal oxygenation could be the ultimate treatment for these refractory hypoxemia patients. We report two cases of patients suffering from severe ARDS who beneficiated from extracorporeal oxygenation, pointing out the interest of this technique during severe ARDS as well as the accessibility and the feasibility of the technique even apart from a specialized center.

Anesthesia management in a child with PHACE syndrome and agenesis of bilateral internal carotid arteries

This is the first case report of successful anesthesia management in a high‐risk neurological procedure in a patient with PHACE syndrome. PHACE syndrome is rare but an important clinical entity. Anesthesiologists should be aware of the neurological, otolaryngogical, and vascular risk associated with this syndrome.