Diaphragm Pacing in Infants and Children

Since 1976 we have implanted bilateral diaphragm pacers in 34 infants and children: 26 with central hypoventilation syndrome (CHS), three with myelomeningocele, and five with quadriplegia. Compared to adults, several modifications have been necessary to achieve effective ventilation in infants and younger children. In all instances, a tracheostomy has been necessary due to impaired neuromuscular control of upper airway patency during pacing. Bilateral pacing has been necessary to achieve adequate ventilation; in the CHS children with normal awake ventilation, bilateral pacing during sleep eliminates the need for positive pressure ventilation. For the remaining children, adequate awake ventilation is achieved with bilateral pacing, thus permitting substantially greater mobility and limiting use of the ventilator to sleep time. Our longest survivor has now been paced for 10.7 years, and in no instance has phrenic nerve damage occurred secondary to electrical stimulation- Our current pacing regime is characterized by moderate respiratory rates (21 breaths/min), long interpulse intervals (95 ms), and short inspiratory times (0.6 sec), resulting in 50%-75% fewer stimuli/min compared to our previous regime. For all infants and children requiring 24-hour ventilatory assistance, our recent successes in maintaining ventilation using significantly fewer stimuli suggest that long-term continuous pacing is a realistic future goal.     

The Diet Quality Index Revised: A Measurement Instrument for Populations

OBJECTIVE: To evaluate a revision of the Diet Quality Index called the Diet Quality Index Revised (DQI-R). DESIGN: The original Diet Quality Index was revised to reflect current dietary guidance, to incorporate improved methods of estimating food servings, and to develop and incorporate measures of dietary variety and moderation. The scoring of the original scale was reversed in direction and expanded to a 100-point scale to improve interpretability. METHODS/SUBJECTS: Data from the 1994 Continuing Survey of Food Intakes by Individuals were used. A sample of 3,202 adults aged 18 and older contributed 2 days of dietary intake data based on 24-hour recalls for the development and revision of various components of the DQI-R. STATISTICAL ANALYSES: Pearson correlation analyses, ordinary least squares regression analyses, and a nonparametric test to determine trends across ordered groups were used. RESULTS: The mean DQI-R score for the 1994 sample was 63.4 of a possible 100-point score. Sample respondents were more likely to have met dietary guidance in the areas of dietary cholesterol (66.9% met goal) and iron intakes (59.6% met goal) relative to the Recommended Dietary Allowances but less likely to have met goals related to fruit servings (19.6% met goal), grain servings (23.1% met goal), and calcium intakes (16.6% met goal) relative to the Recommended Dietary Allowance. There is a statistically significant quantitative and qualitative improvement in all components of the DQI-R as one moves from the lowest grouping of scores to the highest. For example, persons with DQI-R scores less than 40 consumed 43.9% of energy from fat, 72% of the Adequate Intake for calcium, and 6.7% of the recommended servings of fruit per day. In contrast, those with DQI-R scores greater than 80 consumed 24.2% of energy from fat, 101% of the Adequate Intake for calcium, and 137% of the recommended servings of fruit per day. APPLICATIONS: The DQI-R reflects the dietary guidance principles of macronutrient distribution, moderation, variety, and proportionality. Although the index was designed to monitor dietary changes in populations rather than individuals, each index component reflects an aspect of national dietary guidance. Calculation of DQI-R scores for an individual should provide an estimate of diet quality relative to national guidelines, and differences in scores over time should suggest improvement or decline in overall diet quality.     

Low‐Risk Profile for Malignant Ventricular Arrhythmias and Sudden Cardiac Death after Surgical Ventricular Reconstruction

Background: Although it has been recently demonstrated that there was no significant difference in total survival and clinical outcomes between patients who underwent coronary artery bypass grafting (CABG) with or without surgical ventricular reconstruction (SVR), the question of whether or not SVR decreases the arrhythmic risk profile in this population has not been clarified yet. Objective: To determine the real incidence of sudden cardiac death (SCD) and sustained ventricular tachycardia/ventricular fibrillation (sustained VT/VF) in patients following CABG added to SVR and to define their clinical and echocardiographic parameters predicting in‐hospital and long‐term arrhythmic events (SCD + sustained VT/VF). Methods: Pre‐ and postoperative clinical and echocardiographic values as well as postoperative electrocardiogram Holter data of 65 patients (21 female, 63 ± 11 years) who underwent SVR + CABG were retrospectively evaluated. Results: Mean follow‐up was 1,105 ± 940 days. At 3 years, the SCD‐free rate was 98% and the rate free from arrhythmic events was 88%. Multivariate logistic analysis identified a preoperative left ventricular end‐systolic volume index (LVESVI) > 102 mL/m² (odds ratio [OR] 1.4, confidence interval [CI] 1.073–1.864, P = 0.02; sensitivity 100%, specificity 94%) and a postoperative pulmonary artery systolic pressure (PASP) > 27 mmHg (OR 2.3, CI 1.887–4.487, P = 0.01; sensitivity 100%, specificity 71%) as independent predictors of arrhythmic events. Conclusions: Our and previous studies report a low incidence of arrhythmic events in patients following SVR added to CABG, considering the high‐risk profile of the study population. A preoperative LVESVI > 102 mL/m² and a postoperative PASP > 27 mmHg had a good sensitivity and specificity in predicting arrhythmic events. (PACE 2010; 33:1054–1062)     

Multigenetic lesions in infant acute leukaemias: correlations with ALL-1 gene status

The large majority of childhood B-precursor cell acute lymphoblastic leukaemia cases present IgH and TCRδ gene rearrangements. These rearrangements have been widely used as specific markers for monitoring minimal residual disease. However, their prognostic value still remains unclear. In order to determine whether IgH and TCRδ gene rearrangements have any influence on relapse and event-free survival (EFS), we analysed the clinical impact of these genetic characteristics in 51 B-precursor acute lymphoblastic leukaemia patients. 46/51 patients (90.2%) showed IgH gene rearrangements by Southern blot and/or polymerase chain reaction (PCR) analysis. No statistically significant associations were found between IgH gene rearrangement pattern and age, sex, WBC count, immunophenotype, risk factor, relapse or EFS. 27/41 patients (66%) showed Vδ₂Dδ₃ recombination by Southern blot and/or PCR analysis. At a median follow-up of 53 months the estimated 5-year EFS probability was 78 ± 3% for the whole group. The EFS probability among patients with a Vδ₂Dδ₃ recombination pattern in the TCRδ locus was 90 ± 3%, whereas for patients without Vδ₂Dδ₃ recombination was 39 ± 13% ( P  < 0.005).
IgH rearrangement patterns do not appear to influence relapse or EFS probability. However, TCRδ gene rearrangement patterns have a relevant impact on the relapse rate and the EFS probability. Patients with Vδ₂Dδ₃ recombination have better clinical outcome than patients without this recombination, independent of any other prognostic factors.     

Long-term immunogenicity and safety of an inactivated hepatitis A vaccine in haemophilic patients

Summary. As a consequence of recent outbreaks of HAV infection by blood products, 91 patients, haemophiliacs and subjects with bleeding disorders (10 of whom were also anti-HIV positive) susceptible to HAV infection received a formalin-inactivated hepatitis A vaccine (HAVRIX 720 Elisa Units, SmithKline Beecham). Subcutaneous injections were given in the deltoid region at 0, 1 and 6 months. The seroconversion rates and litres, expressed in GMT IU/1, were determined at 1, 2, 6, 7, 12, 18 and 24 months. No adverse reactions to the vaccine were observed. The highest percentage of responders observed was 98.7% in anti-HIV negative and 71.4% in anti-HIV positive patients. The anti-HAV GMT titres were higher in anti-HIV negative than in anti-HIV positive patients. The inactivated hepatitis A vaccine is safe, clinically well tolerated, and provides long-term protection against HAV infection.