Thierry V. Scohy

Alveolar recruitment strategy and PEEP improve oxygenation, dynamic compliance of respiratory system and end-expiratory lung volume in pediatric patients undergoing cardiac surgery for congenital heart disease

Objective:  Optimizing alveolar recruitment by alveolar recruitment strategy (ARS) and maintaining lung volume with adequate positive end‐expiratory pressure (PEEP) allow preventing ventilator‐induced lung injury (VILI). Knowing that PEEP has its most beneficial effects when dynamic compliance of respiratory system (Crs) is maximized, we hypothesize that the use of 8 cm H2O PEEP with ARS results in an increase in Crs and end‐expiratory lung volume (EELV) compared to 8 cm H2O PEEP without ARS and to zero PEEP in pediatric patients undergoing cardiac surgery for congenital heart disease.

Intraoperative cell salvage in infants undergoing elective cardiac surgery: a prospective trial

BACKGROUND For a long time intraoperative cell salvage was considered not to be applicable in paediatric patients due to technical limitations. Recently, new autotransfusion devices with small volume centrifugal bowls and dedicated paediatric systems allow efficient blood salvage in small children. The purpose of this prospective non-randomised study was to determine the impact of intraoperative cell salvage on postoperative allogeneic blood products transfusion in infant patients undergoing cardiac surgery with cardiopulmonary bypass. METHODS Two consecutive cohorts (122 patients) were studied. The first cohort underwent procedures between January 2004 and July 2005 with only blood salvage from the residual volume. The second cohort consisted of patients operated on from August 2005 to December 2006, with additional use of intraoperative cell salvage. The following variables were analysed: peri- and postoperative blood loss, transfusion of homologous blood products and cell salvage product, haematological and coagulation data, measured before, during and after the operation. RESULTS Additional intraoperative cell salvage significantly enhanced the amount of cell saving product available for transfusion (183+/-56 ml vs 152+/-57 ml, p=0.003) and significantly more patients in this group received the cell saving product postoperatively. Consequently, allogeneic blood transfusion was significantly reduced in volume as well as in frequency. We did not observe any adverse effects of intraoperative cell salvage. CONCLUSION Intraoperative cell salvage, employed as an adjuvant technique to the residual volume salvage in infants undergoing first time cardiac surgery with cardiopulmonary bypass, was a safe and effective method to reduce postoperative allogeneic blood transfusion. Considering current cell salvage related expense and the cost reduction achieved by diminished allogeneic transfusion, intraoperative cell salvage in infants demonstrated no economic benefit.

Three-dimensional transesophageal echocardiography in Ebstein's anomaly

Three-dimensional (3D) transthoracic echocardiography has advantages over traditional two-dimensional (2D) echocardiography in visualizing tricuspid valve morphology in Ebsteins anomaly. We describe the application of intra-operative 3D transesophageal echocardiography during a tricuspid valve repair procedure in a patient with Ebsteins anomaly. Intra-operatively three-dimensional transesophageal echocardiographic (3D TEE) data sets revealed morphology and function of the tricuspid valve, right ventricle outflow tract (RVOT) and pulmonary valve before and after repair. Tricuspid valve leaflet morphology and coaptation as visualized with 3D TEE proved to be consistent with intra-operative findings. Analysis of the tricuspid valve, RVOT and pulmonary valve in the multi-planar review (MPR) mode revealed a bicuspid pulmonary valve, which had not been noticed on the preoperative 2D echocardiographic work-up. In this patient with Ebsteins anomaly, 3D TEE provided additional information on morphology and function of tricuspid valve, RVOT and pulmonary valve.

Feasibility of real-time three-dimensional transesophageal echocardiography in type A aortic dissection

Transesophageal echocardiography (TEE) is the fastest method for diagnosing aortic dissection type A and allows 3D TEE, even in hemodynamically instable patients. 3D TEE may provide additional information on aortic morphology, the involvement of coronary arteries by the dissection and aortic valve function. In this regard 2D and 3D TEE might become the diagnostic method of choice in hemodynamically instable patients.

Virtual reality 3D echocardiography in the assessment of tricuspid valve function after surgical closure of ventricular septal defect

BackgroundThis study was done to investigate the potential additional role of virtual reality, using three-dimensional (3D) echocardiographic holograms, in the postoperative assessment of tricuspid valve function after surgical closure of ventricular septal defect (VSD).Methods12 data sets from intraoperative epicardial echocardiographic studies in 5 operations (patient age at operation 3 weeks to 4 years and bodyweight at operation 3.8 to 17.2 kg) after surgical closure of VSD were included in the study. The data sets were analysed as two-dimensional (2D) images on the screen of the ultrasound system as well as holograms in an I-space virtual reality (VR) system. The 2D images were assessed for tricuspid valve function. In the I-Space, a 6 degrees-of-freedom controller was used to create the necessary projectory positions and cutting planes in the hologram. The holograms were used for additional assessment of tricuspid valve leaflet mobility.ResultsAll data sets could be used for 2D as well as holographic analysis. In all data sets the area of interest could be identified. The 2D analysis showed no tricuspid valve stenosis or regurgitation. Leaflet mobility was considered normal. In the virtual reality of the I-Space, all data sets allowed to assess the tricuspid leaflet level in a single holographic representation. In 3 holograms the septal leaflet showed restricted mobility that was not appreciated in the 2D echocardiogram. In 4 data sets the posterior leaflet and the tricuspid papillary apparatus were not completely included.ConclusionThis report shows that dynamic holographic imaging of intraoperative postoperative echocardiographic data regarding tricuspid valve function after VSD closure is feasible. Holographic analysis allows for additional tricuspid valve leaflet mobility analysis. The large size of the probe, in relation to small size of the patient, may preclude a complete data set. At the moment the requirement of an I-Space VR system limits the applicability in virtual reality 3D echocardiography in clinical practice.

Intraoperative transesophageal echocardiography is beneficial for hemodynamic stabilization during left ventricular assist device implantation in children

Background:  Mechanical circulatory support, with a left ventricular assist device (LVAD) is used in an increasing number of children for treatment of advanced heart failure as bridge‐to‐transplant. To date no data are available and no studies have defined the role of intraoperative transesophageal echocardiography (TEE) for hemodynamic stabilization during Centrimag Levitronix centrifugal pump implantation in children.

Comparing the endo-aortic balloon and the external aortic clamp in minimally invasive mitral valve surgery

OBJECTIVES The aim of this study was to assess the differences in perioperative outcomes and complications between the endo-aortic balloon (EAB) and the external aortic clamp (EAC) during primary elective minimally invasive mitral valve surgery (MIMVS) in a single referral centre by one surgeon. Primary outcomes were cardiopulmonary bypass time (CPB), cross-clamp time (CX) and occurrence of postoperative cerebrovascular accidents (CVAs). Secondary outcomes were other perioperative parameters and complications. METHODS We retrospectively analysed 340 consecutive patients who underwent MIMVS for mitral regurgitation (MR), mitral stenosis or combined regurgitation/stenosis between November 2010 and March 2014 in a single referral centre. In total, 221 patients who underwent an isolated mitral valve repair or isolated mitral valve replacement or repair/replacement combined with an atrial fibrillation (AF)-ablation procedure were included. Patients who had previous cardiac surgery or concomitant tricuspid valve surgery, myxoma or atrial septal defect closure surgery were excluded. RESULTS A total of 57 patients (Group A) underwent MIMVS using the EAC and 164 patients (Group B) were operated using an EAB. Preoperative variables showed a significant difference in poor left ventricular function (LVF, P = 0.18) and moderate LVF (P = 0.019). No significant differences were found in CPB-time, cross-clamp time or postoperative CVA. Furthermore, no significant differences were found in complications, 30-day mortality or postoperative echocardiographical MR gradation. Hospital stay, however, was prolonged in Group A (P = 0.001) and maximum troponin T levels were significantly lower in Group B (P = 0.014). In Group B however, 10 procedures were converted (6%) from EAB to EAC. CONCLUSIONS There is no difference in use between the EAB and the EAC in terms of CPB-time and cross-clamp time, complications or MR gradation at discharge. Use of the EAC showed significantly higher postoperative levels of troponin T, implying more myocardial damage, compared with the EAB. In 6% of the cases however, patients were converted from the EAB to the EAC.

A NEW TRANSESOPHAGEAL PROBE FOR NEWBORNS

Current transesophageal probes are designed for adults and are used both in the operating theatre for monitoring as well as in the outpatient clinic for patients with specific indications, like obesity, artificial valves, etc. For newborns (<5 kg), transesophageal echocardiography (TEE) is not possible because the current probes are too big for introducing them into the esophagus. There is a clear need for a small probe in newborns that are scheduled for complicated cardiac surgery and catheterization. We present the design and realization of a small TEE phased array probe with a tube diameter of 5.2mm and head size of only 8.2-7 mm. The number of elements is 48 and the center frequency of the probe is 7.5 MHz. A separate clinical evaluation study was carried out in 42 patients (Scohy et al. 2007).

Defining indications for selective chest radiography in the first 24 hours after cardiac surgery.

OBJECTIVE In the intensive-care unit (ICU), chest radiographs (CXRs) are frequently obtained routinely for postoperative cardiac surgery patients, despite the fact that the efficacy of routine CXRs is known to be low. We investigated the efficacy and safety of CXRs performed after cardiac surgery for specified indications only. METHODS In this observational cohort study, we prospectively included all patients who underwent conventional major cardiac surgery by median sternotomy in the year 2012. On-demand CXRs could be obtained during the first postoperative period for specified indications only. A routine control CXR was performed on the morning of the first postoperative day for all patients who had not undergone a CXR before that time. The diagnostic and therapeutic efficacy values were calculated for all CXRs. Differences were tested using Fishers exact test or χ(2) analysis. RESULTS A total of 1102 consecutive cardiac surgery patients were included in this study. The diagnostic efficacy of CXRs for major abnormalities was higher for the postoperative on-demand CXRs (n = 301; 27%) than for the routine CXRs taken the morning after surgery (n = 801; 73%) (6.6% vs 2.7%, P = .004). The therapeutic efficacy was higher for the on-demand CXRs, whereas the need for intervention after the next-morning, routine CXRs was limited to 5 patients (4.0% vs 0.6%, P < .001). None of these patients experienced a major adverse event. CONCLUSIONS Defining clear indications for selective CXRs after cardiac surgery is effective and seems to be safe. This approach may significantly reduce the total number of CXRs performed, and will increase their efficacy.

Intraoperative transesophageal echocardiography for mediastinal mass surgery improves anesthetic management in pediatric patients

SIR—A 4-year-old, 16-kg girl was referred to our hospital for resection of a large anterior mediastinal mass. Because of the size of the mediastinal mass and the risk of development of catastrophic airway compression and/or cardiovascular collapse during general anesthesia and surgical manipulation, we decided to use intraoperative transesophageal echocardiography (TEE). A micromultiplane TEE transducer was ready to introduce and to use (ultrasound system switched on) during induction of general anesthesia. To our knowledge, this is the first report of intraoperative TEE for large anterior mediastinal mass resection in children. TEE revealed a large mediastinal mass (819 g) compressing the right atrium and guided surgical manipulation. Intraoperative TEE visualizes all information regarding compression, volume status, and function of the right and left heart structures.