Assessing the Risk of Hypoglycemia Secondary to Propranolol Therapy for the Treatment of Supraventricular Tachycardia in Infants.

Supraventricular tachycardia (SVT) is the most common arrhythmia among infants. Prevention of SVT is frequently managed through propranolol therapy. Hypoglycemia is a known adverse effect of propranolol therapy, but little research has been done on the incidence and risk of hypoglycemia in treatment of SVT in infants with propranolol. This study attempts to offer insight into the risk of hypoglycemia associated with propranolol therapy when treating infantile SVT to help inform future glucose screening guidelines. We conducted a retrospective chart review of infants treated with propranolol in our hospital system. Inclusion criteria were infants < 1 year of age who received propranolol for the treatment of SVT. A total of 63 patients were identified. Data was collected on sex, age, race, diagnosis, gestational age, nutrition source (Total Parenteral Nutrition (TPN) vs oral), weight (kg), weight for length (kg/cm), propranolol dose (mg/kg/day), comorbidities, and whether or not a hypoglycemic event was identified (< 60 mg/dL). Hypoglycemic events were identified in 9/63 (14.3%) patients. Of the patients with hypoglycemic events, 9/9 (88.9%) had comorbid conditions. Patients with hypoglycemic events had significantly lower weight and propranolol dose than those without hypoglycemic events. Weight for length also tended to increase risk for hypoglycemic events. The high incidence of comorbid conditions in the patients who had hypoglycemic events suggests that hypoglycemic monitoring may only be necessary in patients with conditions predisposing to hypoglycemia.

Comparison of unmet health care needs in children with intellectual disability, autism spectrum disorder and both disorders combined.

BACKGROUND: The purpose of this study was to assess the unmet health care needs of children with intellectual disability (ID) compared with children with autism spectrum disorder (ASD) and whether access to health insurance coverage is a contributing factor. Children with ID may be masked in the health care system due to increased diagnosis and awareness of ASD. The needs, unmet needs and insurance coverage of children with ID alone, ASD alone, and co-occurring ID and ASD were assessed in this study. METHODS: The 2016 to 2019 United States' Census Bureau National Survey of Children's Health was used to determine differences in unmet needs, care not received and health insurance coverage during the past year for children with ID and/or ASD. Adjusted odds ratios and 95% confidence intervals for care not received were determined controlling for sex, insurance, race, age and parents' highest education level. RESULTS: Children with ID were nearly four times more likely not to receive needed medical care as children with ASD. Results were similar for unmet hearing and mental health care. Children with both ID and ASD were more likely to have unmet health care but less likely to have unmet medical care compared with children with ASD alone. There were no significant differences for unmet dental or vision care. Children with ID were 3.58 (95% confidence interval: 1.6-8.0) times more likely to have inconsistent health insurance compared with children with ASD. CONCLUSIONS: Children with ID alone are more likely to have unmet medical, hearing and mental health care needs than children with ASD alone. Children with co-occurring ID and ASD have a large amount of general unmet health care needs but less unmet medical needs. Children with ID are less likely to have consistent health insurance than children with ASD. This hinders the ability of children with ID to receive quality care. Further research is needed to determine if the diagnosis of ASD in children in the United States is negatively affecting children with ID alone.

Overrepresentation of multiple birth pregnancies in young infants with four metabolic bone disorders: further evidence that fetal bone loading is a critical determinant of fetal and young infant bone strength.

UNLABELLED: The frequency of multiple birth pregnancies, mostly twin pregnancies, was overrepresented in four different groups of young infants with fractures and bone abnormalities. This finding suggests that fetal bone loading through fetal movement is an important determinant of fetal bone formation and its resultant bone strength. INTRODUCTION: It has been suggested that intrauterine confinement related to the multiple birth pregnancy (MBP) may lead to an increased risk for fragility fractures in young infants as a result of decreased fetal bone loading. METHODS: To objectively test this idea, the frequency of MBPs was evaluated in five groups of young infants with bone disorders: (1) infants exposed to prolonged in utero exposure to magnesium, (2) infants with dietary copper deficiency, (3) infants with rickets from vitamin D deficiency, (4) infants with temporary brittle bone disease, and (5) infants with multiple unexplained fractures in which child abuse was the most likely diagnosis. RESULTS: Compared to a control group and controlled for preterm birth, there was a statistically greater frequency of MBPs in each group. CONCLUSIONS: The results of this study suggest the following: (a) The overrepresentation of MBPs (95 % twins) in these five groups indicates that fetal bone loading is a critical determinant of fetal bone strength; (b) fetal and young infant bone strength is a multifactorial characteristic; and (c) infants from MBPs are at increased risk for fragility fractures during the first 12 months of life, and thus may be mistakenly diagnosed as victims of child abuse.

The demographics of the United States haemophilia treatment centre social workers: the results of a national survey.

Social Workers (SWs) are vital members of the multidisciplinary health care teams at Hemophilia Treatment Centers (HTCs) across the US. However, little research has been done to identify the demographics and qualifications of HTC SWs. In response to this lack of data, a subcommittee from the Social Work Working Group sponsored by the National Hemophilia Foundation conducted a national online survey in 2010. The authors attempted to ascertain the demographics and characteristics of SWs who work at HTCs across the country. The purpose of this article is to report the results of this online survey and evaluate the parameters of SW demographics in HTCs. Electronic surveys were sent to 143 HTC SWs. Ten were excluded and 100 were completed and returned, yielding a 75% response rate. The great majority of HTC SWs are women and almost half are middle-aged (aged 40-59). They represent a highly educated, very experienced group of professionals. When asked why respondents stayed in their positions at the HTCs, answers appeared to highly correlate to factors related to the HTC multidisciplinary team model. The high survey response rate of 75% reflects the interest of HTC SWs in obtaining data that describe and quantify their qualifications. This information may serve as validation of the haemophilia SW role in times of funding cuts. It may also give a basis for the recruitment and retention of SWs in the haemophilia field.

Insulin and oral agents for managing cystic fibrosis-related diabetes.

BACKGROUND: Insulin therapy is recommended by the Cystic Fibrosis Foundation when cystic fibrosis-related diabetes has been diagnosed. Diagnosis is based on an elevated fasting blood glucose level greater than 6.94 mmol/liter (125 mg/deciliter) or symptomatic diabetes for random glucose levels greater than 11.11 mmol/liter (200 mg/deciliter). OBJECTIVES: To examine the evidence that, when treated with agents for managing diabetes, people with cystic fibrosis improve their sugar metabolic control resulting in beneficial impact on lung function and the ability to maintain optimal weight. SEARCH STRATEGY: We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register comprising references identified from comprehensive electronic database searches and handsearches of relevant journals and abstract books of conference proceedings. We also handsearched abstracts from pulmonary and North American Cystic Fibrosis Conference symposia. Date of the most recent search of the Group's Trials Register: December 2004. SELECTION CRITERIA: Randomized controlled trials comparing all methods of diabetes therapy for one month or longer in people with cystic fibrosis. DATA COLLECTION AND ANALYSIS: No studies were found which were eligible for inclusion in this review. MAIN RESULTS: Six references to four studies were identified by the searches, but none were eligible for inclusion in the review as they were not randomized controlled trials. AUTHORS' CONCLUSIONS: While some cystic fibrosis centers use oral medications to help control diabetes, a condition which complicates the course of cystic fibrosis, insulin therapy is the recommended and most widely used treatment method. Lung function has been reported to improve with the use of insulin, but this has not been correlated to the degree in which sugar metabolism has been affected. While the Cystic Fibrosis Foundation recommends insulin therapy be used in managing diabetes, this systematic review identifies the need for a multicentre randomized controlled trial assessing both the efficacy of insulin or other insulin-releasing or insulin-sensitizing medications and their possible adverse effects in managing cystic fibrosis-related diabetes.

A multicenter analysis of the choice of initial surgical procedure in tetralogy of Fallot.

A current debate on the surgical management of patients with tetralogy of Fallot (TOF) focuses largely on primary repair vs initial shunt in younger and/or smaller patients. To characterize practice patterns throughout the United States with respect to the choice of initial surgical procedure in patients with TOF, we analyzed data from a multicenter database. This retrospective study focused on 938 patients from 12 institutions who underwent their initial operation during the 10-year period 1986 through 1995. Overall, the percentage of shunts decreased from 35.1% (1986-1990) to 22.0% (1991-1995) (p < 0.0001). The percentage of primary repairs increased accordingly. However, there was marked interinstitutional variability. For the group of patients aged 3 months or less the overall in-hospital mortality was significantly higher than that for older patients for both shunts and repairs. Multiple logistic regression analysis indicated that age, weight, date of surgery, and the interactions between date of surgery and institutional volume and between age and institutional volume were significant predictors of the initial surgical management of TOF. With this model only part of the observed variance could be explained. Other unidentified variables, including "institutional preference," may be significant factors influencing the choice of initial surgical procedure.

Ibutilide induced intraatrial Wenckebach periodicity in the neonatal canine heart.

In nine anesthetized canine neonates, the high right atrium was paced at progressively shorter cycle lengths while recording high right atrial electrograms and left atrial appendage monophasic action potentials before and after the administration of the new Class III agent, ibutilide. Prior to ibutilide administration, 1:1 conduction was maintained from the high right atrium to the left atrial appendage at all paced cycle lengths, down to 160 ms. Following ibutilide, a pattern of intraatrial conduction was observed in two of nine neonates at a cycle length of 160 ms that was consistent with the development of intraatrial Wenckebach periodicity. This represents one of the only demonstrations of drug induced intraatrial Wenckebach periodicity in vivo and suggests that this rarely reported form of atrial conduction block might play a role in ibutilide's clinical efficacy against atrial arrhythmias.

Comparison of the rate dependent effects of dofetilide and ibutilide in the newborn heart.

This study compared the rate dependent changes in atrial and ventricular monophasic action potential duration in the newborn canine heart in response to two Class III antiarrhythmic agents: dofetilide, a pure Ikr blocker, and ibutilide, a Na+ channel opener. Newborn dogs were anesthetized with pentobarbital, vagotomized, and given propranolol to eliminate autonomic responses. A 4 Fr electrical catheter was placed in the right atrium for pacing. Monophasic action potential durations (APDs) at 90% repolarization (APD90) were recorded from the epicardial surface of the left ventricle and atrium with Ag-AgCl2 suction electrodes. APD90 was measured as cardiac cycle length was shortened by pacing, in the control condition and following two doses of dofetilide (n = 8) or ibutilide (n = 9). Slopes of the APD90 versus decreasing paced cycle length (PCL) relationships were then compared. Large dose dependent increases in atrial and ventricular APD90 were observed after dofetilide and ibutilide. In the neonatal atrium, there were no changes in the APD90 versus PCL relationship with either drug, indicating no rate dependency of drug effect. In contrast, in the ventricle, a steeper APD90 versus PCL slope was noted after dofetilide and ibutilide, indicating a significant loss of drug effect at faster heart rates (i.e., reverse rate dependency). In spite of probable different cellular mechanisms of action, the rate dependent characteristics of dofetilide and ibutilide are identical in the neonatal heart. There is no evidence of (reverse) rate dependency in the atrium, predicting that both agents would be effective at rapid atrial tachycardia rates. For both, however, marked reverse rate dependency is observed in the neonatal ventricle.

Temperature dependency of the vagal chronotropic response in the young puppy: an 'environmental-autonomic interaction'.

We investigated the effects of mild hypothermia (34.3 +/- 0.2 degrees C [mean +/- SD]), hyperthermia (40.8 +/- 0.2 degrees C) and hypoxia (PaO2 = 43 +/- 4 mmHg) on the response to heart rate to continuous right vagus nerve stimulation (the 'vagal chronotropic response') in young puppies, aged 5-22 days. Puppies were anesthetized with alpha-chloralose, vagotomized and pre-treated with propranolol (1 mg/kg i.v.) and phentolamine (1 mg/kg, 1-2 mg/kg/h i.v.). Hypoxia (n = 9) did not significantly alter the resting sinus cycle length and did not alter the response of sinus cycle to a 30 s train of 8 Hz right vagal stimulation. Mild hypothermia (n = 8) increased the resting sinus cycle length by 16 +/- 4% and greatly augmented the vagal chronotropic response (from 76 +/- 27% change in the sinus cycle length (normothermia) to 155 +/- 38% (hypothermia)). Both the sinus cycle length and the vagal chronotropic response turned towards pre-hypothermia values with rewarming. Mild hypothermia also increased the negative chronotropic response to 20 micrograms/kg/min i.v. of methacholine (12 +/- 2% change in the sinus cycle length (normothermia) versus 24 +/- 14% (hypothermia)), suggesting that a postsynaptic mechanism is involved in the hypothermia-induced augmentation of the cardiac vagal chronotropic response. In contrast to hypothermia, mild hyperthermia (n = 8) decreased the resting sinus cycle length slightly (-5 +/- 5% change) and significantly attenuated the cardiac vagal chronotropic response (from 88 +/- 28% change in sinus cycle length (normothermia) to 50 +/- 26% (hyperthermia)). These changes were also reversible with the re-establishment of normothermia. This demonstrates that clinically relevant, environmentally-induced changes in body temperature can directly and reversibly modify parasympathetic efferent responses.

Postnatal development of the putative neuropeptide-Y-mediated sympathetic--parasympathetic autonomic interaction.

OBJECTIVE: Intense stellate ganglion stimulation causes a long-lasting inhibition of cardiac vagal responses in adult dogs. This inhibition is thought to result from the release of neuropeptide Y from sympathetic nerve terminals, which, in turn, blocks the release of acetylcholine from parasympathetic neurons. The purpose of this study was to characterize the developmental expression of this autonomic interaction in the dog. METHODS: We studied and compared the effects of 5-min trains of right stellate ganglion stimulation on cardiac chronotropic responses to supramaximal vagal stimulation trains in 10 neonatal dogs, 8 one-month-old puppies, 8 two-month-old puppies and 8 adult dogs. RESULTS: In the adult group, after 5 min of stellate stimulation, inhibition of the vagal chronotropic response was observed in 7 of 8 (87.5%). Inhibition was observed in 100% of the one-month-olds and in 87.5% of the two-month-olds. In contrast, in the neonates, inhibition was observed in only 4 of 10 (40%) (P < 0.05). The maximum percent inhibition of the cardiac vagal response was significantly less in the neonates than in the older puppies (P < 0.001) and adults (P < 0.01), and the summated inhibition also tended to be less in the neonates (P < 0.05 compared to one- and two-month-old puppies). Finally, in 60% of the neonates and 37.5% of all other animals vagal responses after stellate stimulation were facilitated, i.e. at least 20% greater than the pre-stellate stimulation values. CONCLUSION: The putative neuropeptide-Y-mediated, sympathetic-parasympathetic interaction is not fully expressed in the canine neonate. It appears to develop quite rapidly postnatally, being fully expressed by 1 month of age. We hypothesize that this developmental change is likely the result of maturation of sympathetic nervous system function after birth. The facilitation of the vagal chronotropic response, observed in some animals after stellate stimulation, is a new finding, and may represent yet another type of autonomic interaction.