不同剂量雷米芬太尼对小儿心脏手术转机前应激反应的影响

目的 观察雷米芬太尼对小儿心内直视手术转机前心率、血糖、应激反应的影响,探讨适合该类手术的合适的输注剂量.方法 选择本院拟行ASD(12例)及VSD(18例)矫治术患儿30例.男14例,女16例.全麻诱导后至转机前持续泵注丙泊酚6μg·kg-1·min-1和不同输注剂量的雷米芬太尼,依据其剂量不同分为0.5μg·kg-1·min-1组(R0.5组)、1.0 μg·kg-1·min-1组(R1.0组)及2.0 μg·kg-1·min-1组(R2.0组).分别于麻醉前、开胸后及转机前即刻测定其血浆神经肽Y(NPY)、血清皮质醇及血糖水平,记录心率.结果 与麻醉前比较,雷米芬太尼各剂量组心率、血糖和皮质醇水平在开胸和转机前无明显变化,差异均无统计学意义(Pa＞0.05).与麻醉前比较,各剂量组转机前血浆NPY水平显著升高(Pa＜0.05);与R0.5组、R1.0组比较,R2.0组转机前血浆NPY水平显著降低,差异均有统计学意义(Pa＜0.05).结论雷米芬太尼持续输注0.5 ～2.0 μg·kg-1·min-1,能有效抑制先天性心脏病患儿正中开胸心内操作刺激的应激反应,保持临床参数的稳定.     

Noninvasive Cardiac Output Measurement at Rest and During Exercise in Pediatric Patients After Interventional or Surgical Atrial Septal Defect Closure

In the majority of patients, secundum atrial septal defects (ASDs) are treated interventionally or surgically, before the onset of clinical symptoms, between 3 and 6?years of age. Because right-ventricular dimensions usually normalize after ASD closure, it has been assumed that cardiac function and exercise performance also normalize at long-term follow-up. The aim of our study was to determine cardiac index (CI) at rest and during exercise at medium-term follow-up of children who had undergone surgical or interventional closure of ASD because no such reports have been published thus far. Seventeen patients (age range 8.8-17.3?years) who underwent surgical correction were included together with 17 subjects who received an interventional procedure with Amplatzer and Helex occluders (age range 12.2-17.3?years). The study was performed after a median interval of 8.6?years (range 6.5-11.6) after the procedure. Twelve healthy children of comparable age served as controls. CI measurements were performed based on the inert gas-rebreathing method with the Innocor system. For exercise testing, the standard treadmill protocol of the German Society of Pediatric Cardiology was used. CI, stroke volume (SV), and heart rate (HR) were determined at rest and at two standardized submaximal exercise levels (levels 3 and 6). CI increased in all subjects under exercise conditions. Neither SV nor HR displayed significant differences between the three groups either at rest or under exercise conditions. Although HR increased continuously, no increase of indexed SV occurred beyond level 3. Noninvasive determination of CI at rest and during exercise with the IGR method is feasible in the pediatric age group. At medium-term follow-up, we found no significant differences between patients who underwent surgical or interventional ASD closure compared with normal controls.     

Pulmonary Functions Before and After Pediatric Cardiac Surgery

This study aimed to assess pulmonary functions before and after cardiac surgery in infants with congenital heart diseases and pulmonary overflow and to clarify which echocardiographic parameter correlates best with lung mechanics. Between 2008 and 2009, 30 infants with left-to-right shunt congenital acyanotic heart diseases who had indications for reparative surgery of these lesions were assessed by echocardiography and infant pulmonary function tests before the operation and 6 months afterward. Tests using baby body plethysmography were performed to assess the following infant pulmonary functions: tidal volume, respiratory rate, respiratory system compliance (C _rs) and respiratory system resistance, functional residual capacity (FRC), and airway resistance. The mean age of the patients was 10.47 ± 3.38 months, and their mean weight was 6.81 ± 1.67 kg. Ventricular septal defect and combined lesions were the predominant cardiac diseases (26.7 %). Comparison of the infant pulmonary function tests showed a highly significant improvement in all the parameters between the preoperative and 6-month postoperative visits (p < 0.0001). Systolic pulmonary artery pressure had a statistically significant negative correlation with C _rs (r = ?0.493, p = 0.006) and a positive correlation with FRC (r = 0.450, p = 0.013). The findings showed that C _rs had a statistically significant negative correlation with the pulmonary artery size (r = ?0.398, p = 0.029) and the left atrium size (r = ?0.395, p = 0.031), whereas the pulmonary artery size had a statistically positive correlation with effective resistance (r = 0.416, p = 0.022) and specific effective resistance (r = 0.604, p = 0.0001). Surgical correction of left-to-right shunt congenital heart diseases had a positive impact on lung compliance, airway resistance, and FRC. Noninvasive echocardiographic parameters assessing pulmonary vascular engorgement and pulmonary artery pressure were closely related to these infant pulmonary function test indexes.     

Interventional Pediatric Cardiology: State of the Art and Future Directions

Although the interventional pediatric cardiology began in the early 1950s, it was not until the mid-1980s that a full spectrum of transcatheter interventions in children could be undertaken including balloon atrial septostomy which has been in usage since 1966. Enormous developments have occurred even from the mid-1980s to date. In this review, current state-of-the-art for each broad area of therapeutic catheterization is presented. A large variety of lesions could be opened-up or closed, as the case may be and the results of these interventions were either similar to or better than those reported for the alternative surgical therapy. Indeed, therapeutic catheterization techniques have replaced the conventional surgery for many lesions and are threatening to do so for others. However, long-term follow-up results are scanty and are needed. Further miniaturization of catheters/sheaths used in interventional pediatric cardiology and development of new technology for the lesions which are not amenable to currently available transcatheter methods are awaited. The future seems to be bright for interventional pediatric cardiology.     

Reference Values for Second Trimester Fetal and Neonatal Organ Weights and Measurements

To establish accurate reference ranges for the entire second trimester, we documented organ weights, body weight, and linear measurements for 597 fetuses and neonates with gestational ages ranging from 12 to 26 wk. We determined the mean and standard deviation for weights and measurements at each week of gestation using the StatView™ SE + Graphics statistical program. The analyses revealed a linear correlation between the gestational age and, respectively, the toe-heel length, crown-rump length, and crown-heel length. Body and organ weights increase at varying rates throughout the second trimester. The data correlate well with weights and measurements previously published for the latter half of the second trimester, and extend these reference ranges to encompass the entire second trimester.     

Patient Safety and Human Factors in Pediatric Cardiac Surgery

The patient safety movement and human factors studies are becoming an increasingly important part of everyday clinical practice. Pediatric cardiac surgery is a high-risk field that is very much dependent on safe practices and continuous research into improvement of outcomes. This article reviews the main research frameworks, methods used, and current findings in the area of patient safety and human factors within pediatric cardiac surgery.     

Quantifying and Minimizing Radiation Exposure During Pediatric Cardiac Catheterization

This study reports findings from evaluations of new technologies to measure radiation exposure during pediatric cardiac catheterization procedures. A strategy of pulsed fluoroscopy and low power settings resulted in significantly lower patient radiation exposure compared to conventional 60 frames/sec, high-power settings during fluoroscopy. During radiofrequency ablation procedures, thyroid and thoracic skin sites outside the direct fluoroscopic field received minimal radiation exposure. Intrathoracic radiation exposure was measured with the use of an esophageal dosimeter. In conclusion, strategies to reduce total radiation exposure should be employed, radiation dose should be measured, and assessment of radiation skin injury should be included in postcatheterization assessment.     

心肌肌钙蛋白在儿科领域的研究进展

运用单克隆抗体法动态测定血清心肌肌钙蛋白 (cTn)水平 ,并同时测定肌酸磷酸激酶同工酶 ,以利于对比两者的敏感性和特异性 ,发现儿科危急重症患儿血cTn含量较轻症患儿和正常儿显著升高 ,差异具有统计学意义。由于cTn是心肌损害高度敏感和特异性的指标 ,它能发现先前隐藏在肌酸磷酸激酶同工酶正常值范围内的更小的心肌损害 ,因此测定cTn水平 ,有助于诊断心肌损害 ,并确定病情严重程度和判断预后。     

Recognition and Prevention of Neurological Complications in Pediatric Cardiac Surgery

Because of advances in surgical and cardiopulmonary bypass techniques it is now possible to definitively repair the vast majority of congenital heart disease in infancy or childhood. Although the majority of survivors do not have obvious cerebral sequelae, there is increasing disquiet about the high incidence of acute neurological events in the immediated postoperative period as well as evidence that at long-term follow-up there are subtle cognitive and motor deficits in many. Some children are more at risk of neurodevelopmental problems, either because of their cardiac (e.g., extensive aortopulmonary collaterals) or cerebrovascular (e.g., the propensity to large vessel dissection) anatomy or because of genetic predisposition (e.g., to prothrombotic disorders). The incidence may vary with the surgery (e.g., the Fontan operation) and the cardiopulmonary bypass technique necessary to achieve an adequate technical repair (e.g., low or no flow at deep hypothermia). Recognition of the population at risk will lead to prevention of serious sequelae. Data collected in adults may be misleading, and many pediatric units have developed their own practice, but recent studies in animal models of child surgery and in children have produced some evidence to guide management to ensure the optimal cerebral as well as cardiac outcome. Pump flow should be maintained at least 30 ml/kg/min where possible, with inotropic support to maintain blood pressure if necessary. If pump flow must be lowered or circulatory arrest is essential, thorough cerebral cooling to deep hypothermic temperatures is mandatory; a pH-stat strategy may make this easier, but an α-stat strategy may be better in those operations that can be performed at moderate hypothermia. There is no evidence that the available pulsatile pumps offer an advantage. Tissue oxygenation may reach critical levels and a high hematocrit and oxygen tension may reduce the risk of significant hypoxia. There is a risk of embolization in children, which can be reduced with membrane oxygenators and careful monitoring; the role of arterial filtration remains controversial. The only protective agent that can currently be recommended is methylprednisolone to protect the spinal cord (e.g., in operations on the aortic arch). Further studies are needed in this important area.     

Surgical Volume and Center Effects on Early Mortality After Pediatric Cardiac Surgery: 25-Year North American Experience From a Multi-institutional Registry

Mortality after pediatric cardiac surgery varies among centers. Previous research suggests that surgical volume is an important predictor of this variation. This report characterizes the relative contribution of patient factors, center surgical volume, and a volume-independent center effect on early postoperative mortality in a retrospective cohort study of North American centers in the Pediatric Cardiac Care Consortium (up to 500 cases/center/year). From 1982 to 2007, 49 centers reported 109,475 operations, 85,023 of which were analyzed using hierarchical multivariate logistic regression analysis. Patient characteristics varied significantly among the centers. The adjusted odds ratio (OR) for mortality decreased more than 10-fold during the study period (1982 vs. 2007: OR, 12.27, 95 % confidence interval [CI], 8.52–17.66; p < 0.0001). Surgical volume was associated inversely with odds of death (additional 100 cases/year: OR, 0.84; 95 % CI, 0.78–0.90; p < 0.0001). In the analysis of interactions, this effect was fairly consistent across age groups, risk categories (except the lowest), and time periods. However, a volume-independent center effect contributed substantially more to the risk model than did the volume. The Risk Adjusted Classification for Congenital Heart Surgery, version 1 (RACHS-1) risk category remains the strongest predictor of postoperative mortality through the 25-year study period. In conclusion, center-specific variation exists but is only partially explained by operative volume. Low-risk operations are safely performed at centers in all volume categories, whereas regionalization or other quality improvement strategies appear to be warranted for moderate- and high-risk operations. Potentially preventable mortality occurs at centers in all volume categories studied, so referral or regionalization strategies must target centers by observed outcomes rather than assume that volume predicts quality.     

Radiation Exposure by Three-Dimensional Rotational Angiography (3DRA) During Trans-catheter Melody Pulmonary Valve Procedures (TMPV) in a Pediatric Cardiac Catheterization Laboratory

This retrospective study aims to evaluate radiation exposure by three-dimensional rotational angiography (3DRA) during trans-catheter Melody pulmonary valve (TMPV) procedures. 3DRA has been reported to have added value in the management of complex congenital heart disease aiding in the performance of interventional procedures albeit with concerns of higher radiation exposure. We test the hypothesis that 3DRA does not cause additional radiation exposure during TMPV procedures. We analyzed all 81 TMPV procedures performed at St. Louis Children’s Hospital, MO, USA, from January 1, 2011 to December 31, 2014. Dose-area product (DAP), DAP indexed to body weight (DAP/BW), fluoroscopy time (FT), and weight–fluoroscopy time product of each procedure were recorded. We reviewed each procedure’s images to determine whether additional interventions were performed (e.g., pulmonary artery angioplasty or treatment of conduit pseudo-aneurysm). 3DRA was used in 36 % of the procedures. 3DRA group had a higher number of additional procedures performed. The 3DRA group did not differ from the non-3DRA group in DAP, DAP/BW, and weight–fluoroscopy time product. 3DRA does not cause greater radiation exposure during TMPV procedures.