Diurnal variations in recovery times after general anaesthesia in children.

BACKGROUND: Circadian rhythms coordinate almost all physiological functions and are implicated in major disease development. Even though circadian rhythms have a major impact on human health, little is known about how they affect general anaesthesia. The purpose of this study was to understand if the time of day affects the length of time a child needs to achieve readiness for discharge after general anaesthesia for brain MRI. METHODS: A retrospective analysis over a 3 yr period (2013-5) on the length of stay in the postanaesthesia care unit (PACU) before discharge was performed for children (age <18 yr) undergoing brain magnetic resonance imaging as outpatients. PACU duration was correlated to either morning vs afternoon or to time clusters for discharge times (<9 AM, >9 AM <12 PM, >12 PM <3 PM, >3 PM <6 PM, >6 PM). RESULTS: Data from 2340 procedures in children, with median age [inter-quartile range (range)] of 4.7 [2.3-7.25 (0.5-17.8)] yr were available for analysis. The length of stay in the PACU significantly increased over the course of the day with an observed maximum increase of 18 or 19 min (<9 AM vs >6 PM) in children older than 3 or 5 yr, respectively. Subgroup analysis suggested time of day dependent PACU time increase was independent of sex, co-medications, or obstructive sleep apnoea. CONCLUSION: The time of day significantly affects PACU recovery times in children of both genders having brain imaging under general anaesthesia. Children younger than 3 yr might not be affected. Further validation of these findings may guide future strategies to reduce discharge times.

The cellular electrophysiologic effect of a new amiodarone like antiarrhythmic drug GYKI 16638 in undiseased human ventricular muscle: comparison with sotalol and mexiletine.

The cellular electrophysiologic effect of GYKI 16638, a new antiarrhythmic compound was studied and compared with that of sotalol and mexiletine in undiseased human right ventricular muscle preparation by applying the conventional microelectrode technique. GYKI 16638 (5 microM), at stimulation cycle length of 1000 ms, lengthened action potential duration (APD(90)) from 338.9 +/- 28.6 ms to 385.4 +/- 24 ms (n = 9, p > 0.05). This APD lengthening effect, unlike that of sotalol (30 microM), was rate-independent. GYKI 16638, contrary to sotalol and like mexiletine (10 microM), exerted a use-dependent depression of the maximal rate of depolarization (V(max)) which amounted to 36.4 +/- 11.7% at cycle length of 400 ms (n = 5, p < 0.05) and was characterised with an offset kinetical time constant of 298.6 +/- 70.2 ms. It was concluded that GYKI 16638 in human ventricular muscle shows combined Class IB and Class III antiarrhythmic properties, resembling the electrophysiological manifestation seen after chronic amiodarone treatment.

Photoinduced inactivation of T7 phage sensitized by symmetrically and asymmetrically substituted tetraphenyl porphyrin: comparison of efficiency and mechanism of action.

We investigated the efficiency and the mechanism of action of two--one symmetrically and one asymmetrically substituted--glycoconjugated tetraphenyl porphyrins in their photoreaction with T7 phage as a model of nucleoprotein (NP) complexes. A correlation was found between the dark inactivation of T7 and the binding of porphyrins determined by fluorescence spectroscopy. Both types of porphyrin sensitized the photoinactivation of T7, but the slopes of inactivation kinetics were markedly different. There was no correlation between the dark binding and the photosensitizing efficacy of the two derivatives. Inactivation was moderated by 1,3-diphenylisobenzofuran and 1,3-dimethyl-2-thiourea; however, neither of them inhibited T7 inactivation completely. This result suggests that both Type-I and Type-II reactions play a role in the virus inactivation. Optical melting studies revealed structural changes in the protein part but not in the DNA of the photochemically treated NP complex. Polymerase chain reaction analysis of a 555 bp segment of gene 1 and a 3826 bp segment of genes 3 and 4 failed to demonstrate any DNA damage.

Horizontal transmission of Aujeszky's disease virus from sheep to pigs.

Eight 2-month-old merino lambs were inoculated intranasally with different (10(2.0)-10(5.0)TCID50) amounts of Aujeszky's disease virus (ADV). Electron microscopic studies indicated that ADV replicated in extra-neural sites, in the epithelial cells of the mucosa of the upper and lower respiratory tract. Although the virus was excreted continuously in nasal discharges, horizontal transmission to contact lambs failed. The surviving exposed and contact lambs had no demonstrable antibodies against ADV and they were susceptible when challenged by ADV. However, the virus was transmitted to susceptible pigs in contact with the exposed lambs. One of the five contact pigs showed characteristic clinical signs of Aujeszky's disease, developed a nonsuppurative meningoencephalomyelitis and ADV was recovered from the brain, nasal discharge and other organs. Restriction enzyme analysis of DNA from this virus confirmed the sheep origin of the isolate. The other 4 pigs seroconverted. ADV infection in sheep is therefore a possible source of infection for pigs, but the lack of horizontal transmission in sheep was confirmed.

[Ultrasonic follow up of spontaneous regression of neonatal abdominal cystic changes]. / Ujszülöttkori hasi cystosus elváltozások spontán regressiójának követése ultrahang vizsgálattal.

Abdominal cyst was diagnosed in 14 babies by ultrasound examination (9 multicystic dysplastic kidneys, 4 ovarian cysts, 1 bowel duplication). The cysts were followed up in 6 patients by ultrasound, and marked reduction of multicystic dysplastic kidneys was observed in 2 patients, and 1 ovarian cyst was disappeared. Their experience and a review of the literature suggest that conservative management with sonographic reevaluation is an acceptable alternative to surgical therapy in uncomplicated cases.

Hyponatremic seizures after suprapubic catheter placement in 7-year-old child.

We report a case of hyponatremic seizures in a 7-year old boy with spina bifida following cystoscopy and suprapubic catheter placement. Immediate postoperative cystogram and pelvic computed tomogram (CT) after the development of seizures demonstrated a fluid collection from the suprapubic catheter site into the anterior abdominal wall. The subsequent reabsorption of free water from the fluid collection, with the contribution of postoperative hypotonic intravenous fluid administration and possible transient inappropriate antidiuretic hormone (ADH) secretion resulted in acute dilutional hyponatremia and consequent seizures. Strategies to prevent hyponatremia in children during urological procedures, with emphasis on the importance of reserving free water as the irrigation fluid are discussed.

Sugar metabolism in obese children.

In obese children the glucose tolerance curve results in high blood sugar values. A pathologic rise of the serum insulin level may occur even with normal blood sugar curves and the insulin levels tend to be higher in obesity of long standing. In obese children of families with diabetes, post-loading insulin levels were comparatively lower. It is suggested that this weaker insulin response is related to a prediabetic state.

Neonatal abdominal cystic masses: spontaneous regression demonstrated with ultrasound.

Abdominal cyst was diagnosed in 14 babies by ultrasound examination (9 multicystic dysplastic kidneys, 4 ovarian cysts, 1 bowel duplication). The cysts were followed in 6 patients by ultrasound and marked reduction of multicystic dysplastic kidneys was observed in 2 patients, and 1 ovarian cyst fully disappeared. Their experience in agreement with the literature data suggest that conservative management with sonographic reevaluation is an acceptable alternative to surgical therapy in uncomplicated cases.

Reflectometric blood glucose determination in the neonatological intensive care: haematocrit dependence.

The dependence upon haematocrit of the readings of different methods of reflectometric blood glucose determination ( Eyetone /Dextrostix: Reflomat / Reflotest Hypoglycaemie , Reflomat / Reflotest Glucose, Glucometer /Dextrostix) was studied in blood samples adjusted to haematocrit values between 0.47 and 0.90. In general the reflectometric methods measure lower blood glucose concentration if the haematocrit value is enhanced. There is a clear-cut correlation between the rise in haematocrit and the decrease in blood glucose reading. The critical haematocrit level to reach this effect in the Eyetone and Glucometer is 0.60, and in the Reflomat it is 0.80.