Biomedical subjects

John R Hayes

Publications and source records attributed to John R Hayes.

At least 19 recordsLinked to original sources

PubMed2006

Microstructured optical fibers as high-pressure microfluidic reactors.

Deposition of semiconductors and metals from chemical precursors onto planar substrates is a well-developed science and technology for microelectronics. Optical fibers are an established platform for both communications technology and fundamental research in photonics. Here, we describe a hybrid technology that integrates key aspects of both engineering disciplines, demonstrating the fabrication of tubes, solid nanowires, coaxial heterojunctions, and longitudinally patterned structures composed of metals, single-crystal semiconductors, and polycrystalline elemental or compound semiconductors within microstructured silica optical fibers. Because the optical fibers are constructed and the functional materials are chemically deposited in distinct and independent steps, the full design flexibilities of both platforms can now be exploited simultaneously for fiber-integrated optoelectronic materials and devices.

Journal Article↗

PubMed2006

A leap in faith: the impact of removing the surgeon from the level II trauma response.

BACKGROUND: Limitation of resident work hours has created the need to explore alternatives to surgeon presence during initial assessment and resuscitation for selected life-threatening injuries in children. We recently eliminated the requirement for surgeon presence during Level II alerts. The purpose of this study was to evaluate the impact of this change on patient care. METHODS: A retrospective analysis of trauma alert activity was performed using data from our trauma registry. In March 2003, responsibility for level II alerts was transferred from the pediatric surgeons (PSs) to the Emergency Department (ED) physicians. We compared the activity in the 18-month period before this change (period 1; n = 627) to that afterward (period 2; n = 587). Outcome measures included injury severity score, emergency department length of stay, missed injuries, abdominal computed tomography use, and mortality. Data were analyzed using log-rank statistic, chi2, or t test, where appropriate, with significance level at P < .05. RESULTS: During the entire study period, 1499 patients met the trauma alert activation criteria of which 1214 (81%) were level II alerts. The mean injury severity score for period 1 (8.5 +/- 7.3 SD) was similar to period 2 (9.0 +/- 7.1 SD). When ED physicians replaced PS for Level II alerts, ED length of stay increased from 135 minutes to 165 minutes (P < .001). In addition, the use of abdominal computed tomography was significantly decreased (53.6% vs 42.6%; P < .001). However, there were no missed injuries and no significant differences in the rate of mortality. CONCLUSIONS: When ED physicians replaced PS for Level II alerts, trauma room length of stay was increased, but use of abdominal imaging was decreased with no differences in rate of missed injury or mortality. Emergency Department physicians can safely replace PS during Level II alerts. These findings may be useful to institutions experiencing surgical workforce limitations for trauma alerts.

Adolescent↗

PubMed2006

Progressive addition lenses--measurements and ratings.

BACKGROUND: This study is a followup to a previous study in which the optics of several progressive addition lens (PALs) designs were measured and analyzed. The objective was to provide information about various PAL designs to enable eye care practitioners to select designs based on the particular viewing requirements of the patient. METHODS: The optical properties of 12 lenses of the same power for each of 23 different PAL designs were measured with a Rotlex Class Plus lens analyzer. Lenses were ordered through optical laboratories and specified to be plano with a +2.00 diopters add. Measurements were normalized to plano at the manufacturer-assigned location for the distance power to eliminate laboratory tolerance errors. The magnitude of unwanted astigmatism and the widths and areas of the distance, intermediate, and near viewing zones were calculated from the measured data according to the same criteria used in a previous study. RESULTS: The optical characteristics of the different PAL designs were significantly different from one another. The differences were significant in terms of the sizes and widths of the viewing zones, the amount of unwanted astigmatism, and the minimum fitting height. Ratings of the distance, intermediate, and near viewing areas were calculated for each PAL design based on the widths and sizes of those zones. Ratings for unwanted astigmatism and recommended minimum fitting heights were also determined. Ratings based on combinations of viewing zone ratings are also reported. CONCLUSIONS: The ratings are intended to be used to select a PAL design that matches the particular visual needs of the patient and to evaluate the success and performance of currently worn PALs. Reasoning and task analyses suggest that these differences can be used to select a PAL design to meet the individual visual needs of the patient; clinical trials studies are required to test this hypothesis.

Equipment Design↗

PubMed2006

Children and adolescent exposures to atomoxetine hydrochloride reported to a poison control center.

BACKGROUND: Atomoxetine hydrochloride, a selective norepinephrine reuptake inhibitor was FDA approved for patients with attention-deficit/hyperactivity disorder. Little is known about adverse drug reactions of atomoxetine following an overdose among children. The objective of our study was to evaluate the type of atomoxetine adverse drug reactions in relation to dose. METHODS: We evaluated children exposed to atomoxetine reported to a poison center from January-December 2004. RESULTS: Sixty-four cases met all inclusion criteria. Twenty-one patients had an adverse drug reaction (15 at dosage range 0.52-6.25 mg/kg): agitation, headache, erythema, rash, elevated blood pressure and heart rate, nausea, emesis, and lethargy. In 51 patients, weights were known: group 1 (n = 43) received higher than maximum recommended doses >1.4 mg/kg and group 2 (n = 8) received < or = 1.4 mg/kg. There were no differences in adverse drug reactions in group 1 versus 2. Eight patients were admitted to a healthcare facility and all were discharged without any sequelae. Hypertension occurred in 3 of 9 patients for whom blood pressure was recorded. CONCLUSION: At the doses reported, adverse drug reactions did not correlate with atomoxetine dose. Hypertension may occur in some patients following atomoxetine overdose.

Adolescent↗

PubMed2006

Local weather effects on emergency department visits: a time series and regression analysis.

OBJECTIVE: The ability to forecast atypical emergency department (ED) volumes may aid staff/resource allocation. We determine whether deviations from short-term predictions of weather can be used to forecast deviations from short-term predictions of ED volumes. METHODS: In this retrospective study, we attempted to predict the volume of patient visits to an academic pediatric ED based on short-interval local weather patterns (2000). Local temperature and precipitation data in 1- and 3-hour increments were obtained. Precipitation was coded to be present if it exceeded 0.04 in and subclassified as cold rain/snow if the ambient temperature was lower than 40 degrees F. ED visits were categorized as injuries, emergent, or nonemergent visits. For each category of visit, Box-Jenkins Auto-Regressive Integrated Moving Average time-series models were created of natural trends and cycles in temperature and patient volumes. From these models, differences (residuals) between predicted and observed values of these variables were estimated. The correlation between residuals for temperature and ED volumes was derived for various kinds of ED visit, after controlling for type/volume of precipitation. RESULTS: Residuals for ambient temperature controlled for precipitation correlated poorly with residuals for patient volumes, accounting for 1% to 6% of the variability in the volume of injuries, emergent, and nonemergent visits (R2 = 1%, 1%, and 6%, respectively). CONCLUSIONS: Deviations from short-term predictions of temperature correlate poorly with deviations from predictions of patient volume after adjusting for natural trends and cycles in these variables and controlling for precipitation. These weather variables are of little practical benefit for predicting fluctuations in the rates of ED utilization.

Child↗

PubMed2006

Accommodative lag before and after the onset of myopia.

PURPOSE: To evaluate accommodative lag before, during the year of, and after the onset of myopia in children who became myopic, compared with emmetropes. METHODS: The subjects were 568 children who became myopic (at least -0.75 D in each meridian) and 539 children who were emmetropic (between -0.25 D and +1.00 D in each meridian at all visits) participating between 1995 and 2003 in the Collaborative Longitudinal Evaluation of Ethnicity and Refractive Error (CLEERE) Study. Accommodative lag was measured annually with either a Canon R-1 (Canon USA., Lake Success, NY; no longer manufactured) or a Grand Seiko WR 5100-K (Grand Seiko Co., Hiroshima, Japan) autorefractor. Subjects wore their habitual refractive corrections while viewing a letter target accommodative stimulus of 4 D (either in a Badal system or at 25 cm from the subject, designated Badal and near, respectively) or of 2 D (Badal only). Refractive error was measured with the same autorefractor in subjects under cycloplegia. Accommodative lag in children who became myopic was compared to age-, gender-, and ethnicity-matched model estimates of emmetropic values for each annual visit from 5 years before, through 5 years after, the onset of myopia. RESULTS: In the sample as a whole, accommodative lag was not significantly different in children who became myopic compared with model estimates in emmetropes in any year before onset of myopia for either the 4-D or 2-D Badal stimulus. For the 4-D near target, there was only a greater amount of accommodative lag in children who became myopic compared with emmetropes 4 years before onset (difference, 0.22 D; P = 0.0002). Accommodative lag was not significantly elevated during the year of onset of myopia in any of the three measurement conditions (P < 0.82 for all three). A consistently higher lag was seen in children after the onset of their myopia (range, 0.13-0.56 D; P < 0.004 for all comparisons). These patterns were generally followed by each ethnic group, with Asian children typically showing the most, African-American and white children showing the least, and Hispanic children having intermediate accommodative lag. CONCLUSIONS: Substantive and consistent elevations in accommodative lag relative to model estimates of lag in emmetropes did not occur in children who became myopic before the onset of myopia or during the year of onset. Increased accommodative lag occurred in children after the onset of myopia. Elevated accommodative lag is unlikely to be a useful predictive factor for the onset of myopia. Increased hyperopic defocus from accommodative lag may be a consequence rather than a cause of myopia.

Accommodation, Ocular↗

PubMed2006

Comparison of a personalized parent voice smoke alarm with a conventional residential tone smoke alarm for awakening children.

BACKGROUND: Conventional residential tone smoke alarms fail to awaken the majority of children during slow wave sleep. With the objective of identifying a more effective smoke alarm for children, we compared a personalized parent voice smoke alarm with a conventional residential tone smoke alarm, both presented at 100 dB, with respect to their ability to awaken children 6- to 12-years-old from stage 4 sleep and prompt their performance of a simulated self-rescue escape procedure. METHODS: Using a randomized, nonblinded, clinical research design, a volunteer sample of healthy children 6- to 12-years-old was enrolled in the study. Children were trained how to perform a simulated self-rescue escape procedure when they heard a smoke alarm. Each child's mother recorded a voice alarm message, "First name! First name! Wake up! Get out of bed! Leave the room!" For each child, either the voice or tone smoke alarm was randomly selected and triggered during the first cycle of stage 4 sleep, and then the other alarm was triggered during the second cycle of stage 4 sleep. Children's sleep stage was monitored by electroencephalography, electro-oculography, and chin electromyography. The 4 main outcome measures included the number of children who awakened, the number of children who escaped, the time to awakening, and the time to escape. RESULTS: Twenty-four children were enrolled. The median age was 9 years, and 11 (46%) were boys. One half of the children received the parent voice alarm first, and one half received the tone alarm first; however, the order that the alarm stimuli were presented was not statistically associated with awakening or escaping. Twenty-three (96%) of the 24 subjects awakened to the parent voice alarm compared with 14 (58%) to the tone alarm. One child did not awaken to either stimulus. Nine children awakened to their parent's voice but not to the tone, whereas none awakened to only the tone and not the voice. Twenty (83%) of the subjects in the parent voice alarm group successfully performed the escape procedure within 5 minutes of alarm onset compared with 9 (38%) in the tone alarm group. The median time to awaken was 20 seconds in the voice alarm group compared with 3 minutes in the tone alarm group. The median time to escape was 38 seconds in the voice alarm group compared with the maximum allowed 5 minutes in the tone alarm group. When exposed to the tone alarm, older children were more likely to awaken and were more likely to escape than younger children. There was no association between child's age and awakening or escaping for children exposed to the parent voice alarm. There was no association between child's gender and awakening or escaping for either alarm type. CONCLUSIONS: To our knowledge, this study is the first to compare the ability of different types of smoke alarms to awaken children while monitoring sleep stage. The personalized parent voice smoke alarm at 100 dB successfully awakened 96% of children 6- to 12-years-old from stage 4 sleep with 83% successfully performing a simulated self-rescue escape procedure, significantly outperforming the 100-dB conventional residential tone smoke alarm. These findings suggest a clear direction for future research, as well as important fundamental changes in smoke alarm design, that address the unique developmental needs of children. The development of a more effective smoke alarm for use in homes and other locations where children sleep provides an opportunity to reduce fire-related morbidity and mortality among children.

Accident Prevention↗

PubMed2005

Significance of heritability in primary and secondary pediatric hypertension.

BACKGROUND: Patient weight and family history are significant risk factors for the development of hypertension in children. Multiple genetic factors have been identified in primary (essential) hypertension in adults; however, the delineation of genetic factors in the separate populations of children with primary or secondary hypertension are not well understood. Heritability is the proportion of observed variation in a particular trait that can be attributed to an inherited genetic factor in contrast to environmental factors. In the consideration of hypertension, heritability can be assessed in terms of an underlying continuous gradient of the liability for developing hypertension. With this assumption it is possible to compute heritability using hypertension incidence among relatives and described by Falconer. Heritability values range from 0 (no genetic contribution) to 1 (complete genetic contribution). The aim of this study was to determine the genetic contribution to primary and secondary hypertension in a pediatric population through heritability analysis. METHODS: This was a retrospective case-control analysis of medical records of children (n=276) followed in the Pediatric Nephrology Clinic over a 4-year period from 1999 to 2002. There were 192 children and adolescents with primary hypertension (124 male, 68 female, age 0 to 21 years) and 84 children and adolescents with secondary hypertension (46 male, 38 female, age 0 to 21 years). Each hypertensive group served as the control for the other. Estimates of heritability were made using Falconer's method 2. The model assumes independence between the environment and genetic factors and that the joint distribution of liabilities between parent and child are normally distributed. Problems can arise from computing heritability due to dominance within loci, correlations between nongenetic familial effects, or the presence of a major gene. RESULTS: Of the children and adolescents with primary hypertension, 49% had parents with primary hypertension; and of the children and adolescents with secondary hypertension, 24% had parents with primary hypertension. Of the children and adolescents with primary hypertension, 10% had parents with secondary hypertension; and of the children and adolescents with secondary hypertension, 46% had parents with secondary hypertension. The estimated heritability for primary hypertension was 0.84 (SE=0.21). The estimated heritability for secondary hypertension was 1.14 (SE=0.21). As the value was >1, this indicates that the fit of the liability model is poor and that a few genes, or even one major gene, were significantly involved in the causes of secondary hypertension in the children and adolescents studied. CONCLUSIONS: The results suggest that primary and secondary hypertension do not share the same type of genetic profile. Primary hypertension in children and adolescents is likely due to a large number of additive contributions of genes, although a highly correlated environmental component can not be excluded. The continuous liability model is inappropriate for secondary hypertension because the estimate was substantially greater than one. This study supports the model that secondary hypertension in children and adolescents may be related to just a few genes.

Adolescent↗

PubMed2005

Blink rate decreases with eyelid squint.

PURPOSE: We hypothesize that eyelid squint inhibits blink rate. This is part of a larger hypothesis that, because eyelid squint improves vision under conditions of optical defocus and/or glare, and reduced blink rate is assumed to contribute to dry eye symptoms, eyelid squint is part of the mechanism resulting in asthenopia. This study investigates the effect of voluntary eyelid squint on blink activity and on electromyography (EMG) measures from the orbicularis oculi. METHODS: Ten subjects (18 to 38 years of age) performed 3 1-minute trials each (Latin Square order) of voluntary target squint levels of 5%, 20%, 35%, and 50% with respect to previously demonstrated 0% (relaxed) and 100% (maximum) squint levels. EMG recordings using surface electrodes were obtained from the orbicularis muscle. Vertical dimension of the palpebral fissure and eye lid blinks were measured with an ISCAN eye tracker and video recorder. RESULTS: Each target squint level produced significant changes (p<0.0001) in ocular aperture size, EMG power, and EMG amplitude. For target voluntary squint levels of 5%, 20%, 35%, and 50%, the mean squint responses were 24%, 35%, 42%, and 53%, respectively. Blink rate was inversely related to both target squint level and squint response (p<0.0001), decreasing from 15 blinks per minute at 0% squint to 7.5 blinks per minute at 5% target voluntary squint and to 4 blinks per minute at 50% target voluntary squint. CONCLUSIONS: Voluntary eyelid squint significantly reduces blink rate by an average of 50% or more dependent on attempted level. Further study is required to determine if involuntary squint causes the same. All tested levels of voluntary squint resulted in an EMG signal from the orbicularis muscle that is measurably different from resting state. This indicates that EMG can be used as a reliable indicator of eyelid squint.

Adult↗

PubMed2005

Progressive powered lenses: the Minkwitz theorem.

PURPOSE: The Minkwitz theorem, which can be proven to apply to the immediate surface surrounding a line of umbilics, states that astigmatism perpendicular to the line changes twice as quickly as the rate of change of power along the line. Our objective is to test how the Minkwitz theorem applies to the design of progressive addition lenses (PALs). METHOD: Our primary investigation of the astigmatism/power rate relationship used Hoya Tact lenses because they have a relatively large central region with horizontal spherical equivalent power contours and vertical astigmatism power contours. Other PALs were used for subsequent analysis. Lenses were measured with a Rotlex Class Plus lens analyzer. RESULTS: Zone widths in the central region of the Tact lenses exceeded those predicted by the Minkwitz theorem. Above and below this region, zone widths were narrower than predicted. When averaged along the entire corridor, zone widths approximated the Minkwitz theorem. For other PALs, the measured zone widths exceed Minkwitz theorem in the top (distance) and middle (intermediate) corridor but fell short in the lower (near) corridor. Likewise, on average along the entire corridor, they approximate the Minkwitz theorem. CONCLUSIONS: Although the Minkwitz theorem must apply exactly to the immediate locale of an umbilic, deviations from Minkwitz can occur within 2 mm of the corridor. Several factors enable enough local deviation from the Minkwitz theorem to "steer" the astigmatism and affect its magnitude in the peripheral portions of a lens. Although the Minkwitz relationship may be altered in some regions of the corridor, there is a global component to the Minkwitz prediction that applies to PALs. On a global level, the gains and losses of astigmatism along the corridor with respect to the Minkwitz prediction have strong tendency to cancel one another. In the end, it appears the unwanted astigmatism associated with a given power change along a given distance can be redistributed but probably not reduced.

Astigmatism↗

PubMed2005

Comparison of ocular component growth curves among refractive error groups in children.

PURPOSE: To compare ocular component growth curves among four refractive error groups in children. methods Cycloplegic refractive error was categorized into four groups: persistent emmetropia between -0.25 and +1.00 D (exclusive) in both the vertical and horizontal meridians on all study visits (n = 194); myopia of at least -0.75 D in both meridians on at least one visit (n = 247); persistent hyperopia of at least +1.00 D in both meridians on all visits (n = 43); and emmetropizing hyperopia of at least +1.00 D in both meridians on at least the first but not at all visits (n = 253). Subjects were seen for three visits or more between the ages of 6 and 14 years. Growth curves were modeled for the persistent emmetropes to describe the relation between age and the ocular components and were applied to the other three refractive error groups to determine significant differences. results At baseline, eyes of myopes and persistent emmetropes differed in vitreous chamber depth, anterior chamber depth, axial length, and corneal power and produced growth curves that showed differences in the same ocular components. Persistent hyperopes were significantly different from persistent emmetropes in most components at baseline, whereas growth curve shapes were not significantly different, with the exception of anterior chamber depth (slower growth in persistent hyperopes compared with emmetropes) and axial length (lesser annual growth per year in persistent hyperopes compared with emmetropes). The growth curve shape for corneal power was different between the emmetropizing hyperopes and persistent emmetropes (increasing corneal power compared with decreasing power in emmetropes). conclusions Comparisons of growth curves between persistent emmetropes and three other refractive error groups showed that there are many similarities in the growth patterns for both the emmetropizing and persistent hyperopes, whereas the differences in growth lie mainly between the emmetropes and myopes.

Adolescent↗

PubMed2005

Text legibility and the letter superiority effect.

Effects of font design and electronic display parameters upon text legibility were determined using a threshold size method. Participants' visual acuity (inverse of the minimum detection size, representing the threshold legibility for each condition) was measured using upper- and lowercase letters and lowercase words in combinations of 6 fonts, 3 font-smoothing modes, 4 font sizes, 10 pixel heights, and 4 stroke widths. Individual lowercase letters were 10% to 20% more legible than lowercase words (i.e., lowercase words must be 10%-20% larger to have the same threshold legibility). This letter superiority effect suggests that individual letters play a large role and word shape plays a smaller role, if any, in word identification at threshold. Pixel height, font, stroke width, and font smoothing had significant main effects on threshold legibility. Optimal legibility was attained at 9 pixels (10 points). Verdana and Arial were the most legible fonts; Times New Roman and Franklin were least legible. Subpixel rendering (ClearType) improved threshold legibility for some fonts and, in combination with Verdana, was the most legible condition. Increased stroke width (bold) improved threshold legibility but only at the thinnest width tested. Potential applications of this research include optimization of font design for legibility and readability.

Adolescent↗

PubMed2005

Minority status and the risk of serious childhood injury and death.

OBJECTIVE: Minority populations have an increased risk for trauma, but little is known about injury rates for minority children. This study compares the causes, rates and outcomes of traumatic injuries between minority and white children in a statewide population sample. METHODS: A cohort study of 5,973 children (age <16) receiving inpatient care for treatment of acute injuries at the pediatric trauma centers in Ohio from 1999--2001. Case records were analyzed for race, injury type, injury severity, length of stay and demographic information. Supplemental data sources included the 2000 U.S. census and Ohio Vital Statistics death certificates 1996--2001. MAIN OUTCOME MEASURES: Hospital admission rate, mortality rate, length of stay, rate of admission to rehabilitation service. RESULTS: African-American children, who composed the vast majority of the minority population sample, were 7.7 more times likely to sustain a burn or gunshot wound, seven times more likely to be struck by a car, six times more likely to be intentionally injured and over twice as likely to killed by an injury than white children. However, after adjusting for injury severity, they have the same mortality, hospital length of stay and referral rate to rehabilitation as white children. CONCLUSION: Trauma has a far greater impact on minority children than on white children. Research and development of injury prevention initiatives that specifically target minority children are urgently needed.

Adolescent↗

PubMed2004

Abnormal left ventricular mass and aortic distensibility in pediatric dialysis patients.

There is ample evidence that the same pathophysiological processes that affect cardiovascular function in adults with end-stage renal disease (ESRD) also operate in children with ESRD. In adults undergoing hemodialysis (HD), a good correlation has been established between left ventricular mass (LVM) and aortic distensibility (AD) as markers of cardiovascular disease progression; however, this correlation has not been established in children. Therefore, in this retrospective study we investigated some aspects of cardiovascular damage (i.e., LVM, LVMI, and AD) in children with ESRD undergoing HD (n=9) or peritoneal dialysis (PD, n=9), and analyzed the relationship between AD, LVM, LVMI, pre-dialysis, post-dialysis blood pressure (BP), and demographic factors in children and adolescents with ESRD. Both LVM and AD were significantly greater in the dialysis population than in a control population derived from our institutional files (P=0.015, P=0.001). LVM and LVMI in children undergoing HD (92.9+/-83.7 g, 80.1+/-31.1 g/cm) were not statistically different from the values in children on PD (130.0+/-89.2 g, 89.6+/-35.9 g/cm), (P=0.3, P=0.5). AD in children on HD (2.2+/-0.55 cm2* dynes(-1*(10-6)) was significantly lower than in children on PD (2.7+/-0.54 cm2* dynes(-1*(10-6)), (P=0.01). The findings in this study confirm earlier studies that demonstrated that LVMI is greater in children on dialysis. This study also demonstrates that abnormal vascular stiffness, as defined by AD, is present in these children. The degree of vascular stiffness in children receiving HD is greater than in children receiving PD. However, further study is needed to address how control of BP, uremia, and other factors may affect these abnormalities in children with ESRD.

Adolescent↗

PubMed2004

Normal scores for nine maneuvers of the Childhood Myositis Assessment Scale.

OBJECTIVE: To document and evaluate the scores that normal, healthy children achieve when performing 9 maneuvers of the Childhood Myositis Assessment Scale (CMAS). METHODS: A total of 303 healthy children, 4-9 years of age, were scored as they performed 9 CMAS maneuvers. The data were then evaluated to determine whether normal scores for some maneuvers are age and sex dependent. RESULTS: All children were able to achieve maximum possible scores for the supine to prone, supine to sit, floor sit, floor rise, and chair rise maneuvers. All but 2 4-year-olds achieved a maximum possible score for the arm raise/duration maneuver. Performance of the head lift and sit-up maneuvers varied significantly, depending primarily on age. Children in all age groups had less difficulty performing the leg lift than the head lift or sit-up. CONCLUSION: The normative data generated by this study are of value for interpreting the serial CMAS scores of children with idiopathic inflammatory myopathies.

Child↗

PubMed2004

Body mass index in primary and secondary pediatric hypertension.

The objectives of this study were (1) to determine the relationship of body mass index (BMI) to primary or secondary hypertension in children and adolescents and (2) to assess BMI at the age of onset of hypertension in children and adolescents. Patient demographics, BMI, family history, presentation of disease, etiology of hypertension, medication, laboratory data, and findings from other procedures were recorded for all patients with hypertension followed in the Pediatric Nephrology Clinic at Children's Hospital, Columbus, Ohio, over a 4-year period. In total, 314 patients were studied: 218 with primary hypertension and 96 with secondary hypertension. Our patient population (166 males, 148 females) was diverse in age (13+/-6.3 years) and ethnicity (237 Caucasians, 54 African-Americans, 23 other). BMI was greater in patients with primary (27.5+/-9.2 kg/m2) versus secondary (23.9+/-9.3 kg/m2) hypertension (P=0.002). Children with primary hypertension with an increased BMI presented at an earlier age than children with secondary hypertension and an increased BMI. The age of onset (10.5+/-2.6 years) in primary hypertension was related to increased BMI (r=0.12, P=0.001); however, there was no relationship between BMI and age of onset of secondary hypertension (P=0.21). Children whose family members had essential hypertension had increased BMI compared with children without a family history of essential hypertension. Based on the logistic regression model constructed from our data, the likelihood of primary versus secondary hypertension was influenced by the presence of family history of hypertension independent of presence of obesity in the child. In conclusion, increased BMI is more common in children with primary than secondary hypertension; earlier onset of primary hypertension in the pediatric population was associated with increased BMI; the assessment of BMI is important in the evaluation of secondary as well as primary hypertension; the role of obesity in the development of secondary as well as primary hypertension in children merits further study.

Adolescent↗

PubMed2004

Does VATS provide optimal treatment of empyema in children? A systematic review.

PURPOSE: The surgical literature is replete with studies describing methods of treatment for pediatric empyema. The purpose of this report was to perform an evidence-based review of the literature to determine the most effective and appropriate treatment for empyema in infants and children. METHODS: The MEDLINE database was searched for English- and Spanish-language articles published from 1987 through 2002 on the treatment of thoracic empyema in children. Additional unpublished data were obtained by contacting individual study authors. There were no multiinstitutional prospective studies; all were retrospective, institutional series. A true meta-analysis could not be performed because of inherent institutional bias and variability in outcome measures among studies. A Kruskal-Wallis nonparametric test was used to compare methods detailed in the individual studies. RESULTS: Forty-four retrospective studies with a total of 1,369 patients were available for analysis. Four treatment strategies were compared: chest tube drainage alone (16 studies, 611 patients), chest tube drainage with fibrinolytic instillation (10 studies, 83 patients), thoracotomy (13 studies, 226 patients), and video-assisted thoracoscopic decortication (VATS; 22 studies, 449 patients). Outcome measures common to the majority of studies included length of stay, fever duration, l of antibiotic therapy duration, and duration of chest tube drainage. Patients undergoing early VATS or thoracotomy had shorter length of stay (P =.003). There was a trend for shorter duration of postoperative fever compared with chest tube alone or with fibrinolytic therapy, but this did not reach statistical significance (P =.055). There was no statistical difference in chest tube duration between methods. There was no trend correlating antibiotic use with treatment methods, length of hospital stay, duration of fever, or length of chest tube requirement. CONCLUSIONS: Early VATS or thoracotomy leads to shorter hospitalization. The duration of chest tube placement and antibiotic use is variable and does not correlate with treatment method. A carefully designed, multiinstitutional, randomized study would lead to the development of evidence-based standards that may optimize the treatment of thoracic empyema in children.

Child↗

PubMed2004

Effectiveness of pretreatment in decreasing adverse events associated with pamidronate in children and adolescents.

STUDY OBJECTIVES: To assess the effectiveness of pretreatment with ibuprofen or acetaminophen compared with no pretreatment in decreasing adverse events in children and adolescents receiving the first and second series of pamidronate therapy; and to compare the effectiveness of ibuprofen versus acetaminophen for prevention of adverse events associated with pamidronate infusion. DESIGN: Retrospective case review. SETTING: Children's hospital. PATIENTS: Twenty-seven children and adolescents aged 3-21 years receiving pamidronate therapy. MEASUREMENTS AND MAIN RESULTS: Data for patient demographics, medical history, genetic history of disease, pamidronate infusion dosage, and concurrent drug therapy were collected. Adverse drug events secondary to pamidronate infusion and subsequent drug therapies received were documented. Data were categorized by presence or absence of pretreatment and analyzed by cross-tabulation to determine whether the presence of adverse events differed between groups (no pretreatment, acetaminophen pretreatment, and ibuprofen pretreatment). Fewer adverse events were reported in patients receiving ibuprofen (17% of patients) versus acetaminophen (83%). Differences in presence of fever (chi2 = 10.5, p = 0.005) and bone pain (chi2 = 7.3, p = 0.027) among the three pretreatment groups were also statistically significant. CONCLUSION: Pretreatment with ibuprofen or acetaminophen appears to decrease the occurrence of adverse events from pamidronate therapy. However, adverse events seem less likely to occur with ibuprofen. Further study is necessary to determine the relationship between occurrence of adverse events, other possible treatment strategies, and patient adherence with pamidronate therapy.

Abdominal Pain↗