Hemodynamic effects of dobutamine and dopexamine after cardiopulmonary bypass in pediatric cardiac surgery*

Background: After surgical repair of congenital heart disease, inotropic support is sometimes necessary to wean from cardiopulmonary bypass. In pediatric cardiac surgery, dobutamine and dopamine are often used as inotropic support. Dopexamine is a synthetic catecholamine, which has positive inotropic and vasodilating properties. Because the hemodynamic effects of catecholamines are modified after cardiopulmonary bypass, the aim of this study was to investigate the effects of dobutamine and dopexamine on cardiac index and systemic vascular resistance index after cardiopulmonary bypass in pediatric cardiac surgery. Methods: The study was performed in a prospective, randomized, and double‐blinded cross‐over design. The investigation included 11 children for elective, noncomplex congenital heart surgery. After weaning from cardiopulmonary bypass and a 20‐min period of steady state, children received either 2.5 μg·kg^?1·min^?1 dobutamine or 1 μg·kg^?1·min^?1 dopexamine for 20 min. Cardiac index (transpulmonary thermodilution), mean arterial pressure, central venous pressure, stroke volume, systemic vascular resistance, and central venous oxygen saturation were determined. The primary outcome variable was cardiac index. Results: No difference in cardiac index was observed between the two groups (P = 0.594). Both drugs increased cardiac index, dopexamine from 3.9 ± 0.6 to 4.7 ± 0.8 l·min^?1·m^?2 (P = 0.003) and dobutamine from 4.1 ± 0.7 to 4.8 ± 0.7 l·min^?1·m^?2 (P = 0.004). During treatment with dobutamine, children presented with significantly higher mean arterial pressure (P = 0.003) and systemic vascular resistance index (P = 0.026). Conclusions: This trial demonstrates that low‐dose dobutamine and dopexamine both increase cardiac index during pediatric cardiac surgery but with different hemodynamic effects.     

Hypothermie bei Traumapatienten

Coincidental hypothermia after trauma can aggravate the severity of injury and it therefore makes sense to monitor the body temperature in the preclinical setting. In a prospective study, incidence and degree of severity of hypothermia were analysed as a function of injury pattern and preclinical care. A main factor of hypothermia was severity of injury measured by the injury severity score (ISS 24.0±15.5 versus 8.3±7.8) and the revised trauma score (RTS 5.6±1.8 versus 7.3±1.1). Of the patients with multiple trauma, 88.2% were hypothermic when administered to hospital, but no reason was found concerning the rescue methods (e.g. rescue time, whole duration, weather). An increase in the rate of hypothermia was seen only after long lasting incarceration. A multivariate data analysis showed, that in addition to ISS and RTS patient age (p=0.014) was primarily responsible for hypothermia after trauma, whereas no dependency was demonstrated for other factors. Thus, parts of this analysis are in contrast with other studies. Overall approximately 50% of trauma patients in the emergency unit suffer from hypothermia, but at this time point changes in physiological control mechanisms are not yet detectable. Nevertheless prevention of hypothermia is very important in the preclinical setting.     

The hospital record of the injured child and the need for external cause-of-injury codes. American Academy of Pediatrics. Committee on Injury and Poison Prevention, 1998-1999

Proper record-keeping of emergency department visits and hospitalizations of injured children is vital for appropriate patient management. Determination and documentation of the circumstances surrounding the injury event are essential. This information not only is the basis for preventive counseling, but also provides clues about how similar injuries in other youth can be avoided. The hospital records have an important secondary purpose; namely, if sufficient information about the cause and mechanism of injury is documented, it can be subsequently coded, electronically compiled, and retrieved later to provide an epidemiologic profile of the injury, the first step in prevention at the population level. To be of greatest use, hospital records should indicate the "who, what, when, where, why, and how" of the injury occurrence and whether protective equipment (eg, a seat belt) was used. The pediatrician has two important roles in this area: to document fully the injury event and to advocate the use of standardized external cause-of-injury codes, which allow such data to be compiled and analyzed.     

ANAL TONOMETRY A Diagnostic Help in Hirschsprung's Disease1

Manometrical measurements of reflex responses in the internal anal sphincter were made in 93 patients. In normal controls, a relaxation was obtained within the internal sphincter after distension of the rectum. Patients suffering from Hirschsprung's disease showed either a contraction in the muscle or an absence of sphincteric response. In 17 cases, where the diagnosis of Hirschsprung's disease was established by conventional means, the diagnosis was confirmed by anal tonometry in 13 cases and disproved by this method in 4 cases. The subsequent clinical course and histological findings have verified the diagnosis obtained by tonometry. In one patient it was not possible to make the diagnosis by means of the usual methods, anal tonometry showed Hirschsprung's disease and this was subsequently confirmed by biopsy.     

Radiological assessment of constipation

A scoring system for faecal loading was constructed by two experienced observers using the abdominal radiographs of 20 children. Four other observers independently graded the radiographs using this system and there was a high degree of agreement between all six observers (p < 0.001), suggesting that radiological assessment of constipation can be standardised.     

The necdin gene is deleted in Prader-Willi syndrome and is imprinted in human and mouse

Human chromosome 15q11-q13 contains genes that are imprinted and expressed from only one parental allele. Prader-Willi syndrome (PWS) is due to the loss of expression of one or more paternally expressed genes on proximal human chromosome 15q, most often by deletion or maternal uniparental disomy. Several candidate genes and a putative imprinting centre have been identified in the deletion region. We report that the human necdin-encoding gene (NDN) is within the centromeric portion of the PWS deletion region, between the two imprinted genes ZNF127 and SNRPN. Murine necdin is a nuclear protein expressed exclusively in differentiated neurons in the brain. Necdin is postulated to govern the permanent arrest of cell growth of post-mitotic neurons during murine nervous system development. We have localized the mouse locus Ndn encoding necdin to chromosome 7 in a region of conserved synteny with human chromosome 15q11-q13, by genetic mapping in an interspecific backcross panel. Furthermore, we demonstrate that expression of Ndn is limited to the paternal allele in RNA from newborn mouse brain. Expression of NDN is detected in many human tissues, with highest levels of expression in brain and placenta. NDN is expressed exclusively from the paternally inherited allele in human fibroblasts. Loss of necdin gene expression may contribute to the disorder of brain development in individuals with PWS.      

Supratentorial ependymoma: CT appearance

The computed tomographic appearances of 22 biopsy-proved supratentorial ependymomas were analyzed. Supratentorial ependymomas were usually intraparenchymal, larger than 4 cm, and cystic. Contrast enhancement was moderate to intense, with homogeneous or ring-enhancement patterns commonly seen. Intratumoral calcification was present in one-third of the cases, while hydrocephalus and peritumoral edema were seen in 50%. Intratumoral hemorrhage was not a characteristic of the lesion. In contrast to cellular ependymomas, malignant ependymomas and ependymoblastomas demonstrate higher attenuation prior to administration of contrast material, more intense enhancement, lower frequency of calcification within the tumor, and less distinct margination.     

Randomized trial of umbilical arterial catheter position: clinical outcome

In order to determine if umbilical arterial Catheter position affects the incidence of necrotizing enterocolitis, clinical outcome was analysed in 308 infants whose umbilical arterial catheter had been randomly allocated to a high ( n =162) or a low ( n =146) position. Necrotizing enterocolitis was classified as suspected or confirmed; all renal, lower limb and local catheter complications were also recorded. High umbilical arterial catheters were in place for longer than low catheters, provided more samples and were removed as an emergency less often. Lower limb blanching and cyanosis were more common with low catheters. Eleven cases of confirmed necrotizing enterocolitis occurred in the "high" group and nine in the "low" group. One case of fatal aortic thrombosis was encountered in the high group. Positioning umbilical arterial catheters in a high position allowed longer functional use and did not increase the incidence of necrotizing cnterocolitis.     

Nordic children with myelomeningocele. Parents' assessments of the handicap and physicians' classifications of the disabilities

The differences between parents' assessments of their child's handicap and professionals' assessment of disabilities were studied in 486 Nordic children with myelomeningocele aged 4–18 years. Although disability and handicap are conceptually different, agreement between the parents' assessments of the handicap and the degree of disability according to Lorber's classification was found in 51% of cases. The parents' assessments showed close agreement with overall disability according to Lagergren's method in 45% of cases. The factors most strongly associated with parental assessment of the handicap were the child's motor disability, intellectual functioning, faecal and urinary incontinence and the parents' inclination to feel inadequate with respect to the child's needs. Data from professional assessment of disabilities alone are of limited value in understanding the impact of disabilities on the daily life of a child.