BACKGROUND: When infrared (IR) radiation is conducted through water, its long-wave parts (called IR-B and IR-C) are filtered out in favour of the short-wave IR-A band. Since the former are normally absorbed in the outer layers of skin, water-filtering results in a reduced risk of superficial burns and a better penetration into tissues. This effect which in solar radiation results from its passing through the water vapour of the earth's atmosphere, has now been successfully imitated in radiant heaters. In this study, the potential benefits of water-filtered as compared to conventional infrared radiation in obstetrics and neonatology were examined. MATERIALS AND METHODS: To this end, three methodological approaches were made, namely: 1. Comparative physical measurements of radiant power density in several clinically used IR-sources, 2. physiological simulation experiments on the surface and depth effects of either type of radiation (performed on human adults and an artificial tissue phantom), and 3. clinical observations on the protective effects of the novel IR-A-radiators in incubator nursing and primary care of preterm neonates. RESULTS AND DISCUSSION: Although the absolute radiant power density was equivalent in a conventional and a novel heating device, the IR-A radiation proved to result in a markedly reduced superficial overheating of tissues. In addition, it exceeded conventional IR radiation in its ability to pass through incubator walls, thus lowering the risk of cooling in preterm neonates during nursing procedures. Moreover, when used as a complementary source of heat in the delivery room, IR-A radiation exerted a preventive effect against hypothermia during the subsequent transport of patients to the neonatal intensive care unit, probably due to the rapid build-up of heat deposits in peripheral tissues. CONCLUSIONS: In view of these benefits which are reinforced by a greatly diminished evaporation effect, water-filtered IR-radiation seems to make a promising contribution to the thermal protection of preterm neonates.

Adult↗

PubMedDate not supplied

[Infant botulism and sudden infant death syndrome].

Infant botulism represents a distinct entity of botulism. Ingestion of the ubiquitously present spores of Clostridium botulinum leads to germination of the organism and neurotoxin production in the infant intestine. Symptoms typically develop gradually in contrast to classical food botulism in which an acute onset of symptoms shortly after the ingestion of preformed toxin in a food is characteristic. Microbiologically, the diagnosis is established by identification of Clostridium botulinum organism and toxin in stool specimen. However, positive results in these tests provide only indirect evidence for the clinical relevance of the neurotoxin since asymptomatic carriers have been found. The toxin irreversibly blocks the release of acetylcholin from the motoric end plate which results in muscle weakness and paralysis. Depending on the amount of toxin produced, infant botulism exhibits a broad clinical spectrum ranging from oligosymptomatic forms to a fulminant course with acute respiratory failure within hours leading to sudden death. Unrecognized mild forms or beginning muscle weakness can be a co-factor for other risk factors of sudden infant death (SIDS). In studies analyzing infants who died from SIDS, botulism bacteria or toxin were found in up to 20 % of cases. Infant botulism therefore represents an important differential diagnosis of unexplained and inconclusive muscular hypotonia in the first year of life.

Acetylcholine↗

PubMedDate not supplied

Neonatal platelets from cord blood and peripheral blood.

The haemostatic system in neonates is different from that of adults, possibly contributing to an increased incidence of bleeding disorders, such as intracranial hemorrhage. In this study, we analyzed platelets from cord blood and peripheral blood, collected at three time points after delivery from 20 term and 37 preterm neonates as well as blood from 20 healthy adults. Platelet membrane glycoproteins (GP) were quantified and P-selectin expression and PAC-1 binding ability before and after stimulation with TRAP were analyzed by whole blood flow cytometry. We found no significant differences in neonatal platelets from cord blood and peripheral blood within the first 24h of life. Platelets from infants less than 30 weeks of gestation expressed lower levels of GP (33271+/-9381 vs. 44085+/-17287 for GPIIIa, P<0.05) and were less reactive than platelets from term newborns (4.3+/-3.3 vs. 20.1+/-11.8% PAC-1 positive platelets after stimulation with TRAP, P<0.05). A significantly lower level of GPIIb/IIIa expression on platelets from peripheral blood was seen in term newborns as well as preterm infants, compared to adults. There was only a partial enhancement in the degranulation ability (alpha-granules) (13.4+/-12.3 vs. 50.3+/-16.1% P-selectin positive platelets, P<0.05) and no significant increase for PAC-1 binding (13.6+/-10.9 vs. 15.3+/-5.9% PAC-1 positive platelets, P=0.8) during the first 12 days of life. In conclusion, we could demonstrate that neonatal platelet reactivity increases with gestational age.

Acid Phosphatase↗

PubMedDate not supplied

Angiographic nephrectomy using iodinated contrast agent.

Diatrizoate meglumine and sodium (Renografin-76) was perfused in an obstructed renal artery in 13 dogs. Intense and prolonged accumulation of contrast agent ("contrast staining") was achieved in all animals. Repeat injection was frequently necessary to enhance staining. Renin output from the stained kidneys was lower than that from the opposite kidneys. Angiography at 14-18 weeks demonstrated a marked decrease in renal size in all dogs, with complete occlusion of the renal artery in two dogs. No collateral circulation was discerned. Grossly, all experimental kidneys were uniformly shrunken. Histologically, diffuse renal infarction was evident with coagulative necrosis. Contrast staining is an effective method for uniform destruction of renal tissue.

Animals↗

PubMedDate not supplied

Outbreak of systemic aspergillosis in a neonatal intensive care unit.

Small pre-term neonates are susceptible to cutaneous aspergillosis because of their immature immune system and because of the vulnerability of their skin. In addition, the common therapy with broad-spectrum antibiotic drugs and corticoids creates a favourable milieu for fungal superinfections. We present four pre-term neonates who succumbed to cutaneous aspergillosis that subsequently developed into a systemic infection. The source of the infection proved to be contaminated latex finger stalls. Three of the four patients died. The poor prognosis for systemic aspergillosis can only be improved by an early therapy with amphotericin B, possibly in liposomal form.

Aspergillosis↗