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Monitoring for the anticoagulant effect of unfractionated (UFH) at the point of care using activated clotting time in real time is vital where risk of thrombosis is high. Although monitoring UFH effect is a routine and important task, changing from one ACT instrument type or technology to another must be preceded by a clinical and statistical evaluation to determine the suitability and repeatability and establish normal and treatable ranges of this newer instrument. In this multi-center prospective evaluation we tested 1236 paired ACT+ samples, and 463 paired ACT-LR samples (1699 total) from enrolled study subjects. Clinical settings included CVOR cardiopulmonary bypass, at the beside in extracorporeal life support (ELS), the Cardiac Catheterization Lab (CCL) during diagnostic studies and percutaneous coronary interventions (PCI), interventional radiology procedures and EP interventions. This study found more consistent clinical performance from the GEM Hemochron 100 as compared to the current clinical model, the Hemochron Signature Elite. The bias of GEM Hemochron 100 for ACT+ and ACT-LR was greatest in the setting of the CVOR where ACT levels were high. ACT-LR measurements by the GEM Hemochron 100 were comparable to the SE when performed in settings of CCL, ECM, EP and ICU. Results obtained for both ACT-LR and ACT+ in all clinical settings in this study using the GEM Hemochron 100 are as accurate and more repeatable as those with the current clinically available Signature Elite.

Sedation with chloral hydrate or anesthesia using propofol allow ocular examination and testing in young children, but these drugs may affect electrophysiologic recordings. We compared the flash and pattern ERGs and VEPs recorded with each drug in a cohort of young children enrolled in a prospective study of optic nerve hypoplasia (ONH) syndrome. ERGs and VEPs to light-adapted, standard, full-field flashes, to standard and steady-state pattern-reversal (PR) were recorded with cycloplegia in 9 participants. Age range at the first session, with chloral hydrate was 8–23 mo; at the second session with propofol it was 20–29 mo. Examiners masked to the drug and clinical conditions measured the waveforms for longitudinal, paired comparisons between the sessions. Flash ERG amplitudes did not differ between sessions; peak times were longer at the second session (propofol) by clinically insignificant amounts ( 10 mo between sessions (n = 5, 10 eyes) but not for those with a shorter inter-test interval ( 0.05, n = 4). Magnitudes of the steady-state PERGs did not differ between tests but the waveforms had earlier peaks at the second test with propofol. Flash VEP waveforms were present in 10/18 eyes and showed 72% agreement for recordability between sessions. Standard pattern VEPs were recordable in only a few eyes in this cohort with ONH. Light-adapted flash ERG waveforms were generally similar with chloral hydrate and with propofol. Larger PERGs with later peaks, found in the second session (propofol) could reflect maturation of the PERG generators, as the differences found were associated with a greater age difference between the sessions, but we do not rule out that small differences in the waveforms may be drug-related. There are insufficient VEP data from these children with ONH to identify drug-related or maturational effects on VEPs.

Pattern electroretinograms (PERGs) have inherently low signal-to-noise ratios and can be difficult to detect when degraded by pathology or noise. We compare an objective system for automated PERG analysis with expert human interpretation in children with optic nerve hypoplasia (ONH) with PERGs ranging from clear to undetectable. PERGs were recorded uniocularly with chloral hydrate sedation in children with ONH (aged 3.5–35 months). Stimuli were reversing checks of four sizes focused using an optical system incorporating the cycloplegic refraction. Forty PERG records were analysed; 20 selected at random and 20 from eyes with good vision (fellow eyes or eyes with mild ONH) from over 300 records. Two experts identified P50 and N95 of the PERGs after manually deleting trials with movement artefact, slow-wave EEG (4–8 Hz) or other noise from raw data for 150 check reversals. The automated system first identified present/not-present responses using a magnitude-squared coherence criterion and then, for responses confirmed as present, estimated the P50 and N95 cardinal positions as the turning points in local third-order polynomials fitted in the −3 dB bandwidth [0.25 … 45] Hz. Confidence limits were estimated from bootstrap re-sampling with replacement. The automated system uses an interactive Internet-available webpage tool (see http://clinengnhs.liv.ac.uk/esp_perg_1.htm ). The automated system detected 28 PERG signals above the noise level (p ≤ 0.05 for H0). Good subjective quality ratings were indicative of significant PERGs; however, poor subjective quality did not necessarily predict non-significant signals. P50 and N95 implicit times showed good agreement between the two experts and between experts and the automated system. For the N95 amplitude measured to P50, the experts differed by an average of 13 % consistent with differing interpretations of peaks within noise, while the automated amplitude measure was highly correlated with the expert measures but was proportionally larger. Trial-by-trial review of these data required approximately 6.5 h for each human expert, while automated data processing required

Background Hypopituitarism and obesity are causes of major lifelong morbidity in patients with optic nerve hypoplasia (ONH). Growth hormone deficiency (GHD) affects the majority of children with ONH, though the degree of deficiency and variability of early growth patterns range from early severe retardation to normal initial growth. The utility of early GH replacement for improving anthropometric, body composition, and lipid outcomes in patients with ONH and GHD, especially those with normal initial height velocity, is unknown. This study examines the effects of GH replacement in a cohort of children with ONH and GHD. Methods Controlled clinical trial from 2005–2014. The study included 17 children with ONH and untreated GHD. Those meeting criteria for growth deceleration were assigned to treatment with recombinant human growth hormone (n = 5) while those with normal height velocity were randomized either to treatment (n = 5) or to observation (no intervention, n = 7). Study duration was 3 years. Primary outcome measures included stature, weight, weight-for-stature, and BMI standard deviation score (SDS) at study completion. Results Subjects on GH, irrespective of entry growth trajectory, grew more on average in stature than controls by a difference of 0.98 SDS by study end; this effect persisted after adjusting for baseline overweight status. Treatment had an effect on weight SDS only after adjusting for initial overweight status, resulting in an average increase of 0.83 SDS more than controls. Subjects who were overweight at the outset experienced greater gains in both weight and stature SDS. Treatment had no statistically significant impact on weight-for-stature or BMI SDS. A reduction in body fat percentage was observed in those treated, both before (−6.1 %) and after (−4.3 %) adjustment for initial overweight status. Conclusion Early GH replacement has a positive effect on short-term statural outcomes in children with ONH and GHD, even in those exhibiting normal initial linear growth. Results were less conclusive regarding treatment effects on body composition and lipids.

The purpose of the study is to characterise retinal function using light-adapted electroretinograms (ERGs) in a series of young children with ONH, congenital dysplasia of retinal ganglion cells. ERGs were recorded with chloral hydrate sedation in 27 children with ONH (18 with bilateral and 9 with unilateral ONH, age 4-35 months) and an adult reference population (n = 12). Stimuli included ISCEV standard flash, oscillatory potentials (OPs) and standard flicker as well as a light-adapted luminance-response series (photopic hill). The disc diameter to disc macula (DD:DM) ratio was measured from fundus photographs. The results are eyes with ONH, classified by DD:DM, were severe (or=0.15, n = 22), moderate (0.16-0.30, n = 22), mild (0.31-0.35, n = 1), and fellow eyes (0.35, n = 9), all had prolonged ERG implicit times and smaller i-waves than those of adults. Eyes with moderate or severe ONH also had smaller amplitudes for OPs and flicker ERGs and required stronger flashes to obtain the peak b-wave amplitude. Abnormalities of the photopic hill were a common but inconsistent feature of ONH and were not indicative of ONH severity. Abnormalities of the photopic hill of the ERG suggest that some cases of ONH may have retinal dysfunction with specific deficits in the ON or OFF pathways of the retina. ONH is a complex and heterogeneous condition that may involve dysfunction distal to the retinal ganglion cells.

The congenital malformation known as optic nerve hypoplasia (ONH) has been recognized in the past 30 years as an epidemic cause of congenital blindness. It was believed to occur either as an isolated anomaly or as a component of the syndrome of septo-optic dysplasia, which has evolved to include midline brain malformations and hypopituitarism. Evidence now suggests that ONH infrequently occurs in isolation. Most afflicted children will have hypothalamic dysfunction and/or neurodevelopmental impairment, regardless of MRI findings or severity of ONH. Adverse outcomes can often be ameliorated with early intervention. Thus, the syndrome of ONH should be suspected in all infants with signs of hypothalamic dysfunction or vision impairment.