Control of temperature during newborn transport: An old problem with new difficulties

Objective: To explore any changes in temperature control during neonatal emergency inter-hospital transport between 1977 and 1996.
Methods: Records were reviewed of all infants undergoing emergency transfer by the statewide Victorian Newborn Emergency Transport Service (NETS). Per axillary temperatures were recorded prospectively on arrival of transport team and at conclusion of transfer for all infants.
Results: The rate of hypothermia (<36.0°C) when NETS reached the infant has decreased overall (22% in 1977–79 to 7% in 1995–96) and for all weight groups; although in 1995–96 hypothermia was present in 36% of infants less than 1000g when NETS arrived. The rate of hypothermia (<36.0°C) at the end of the transfer has remained at 3% overall for many years. The rate of hyperthermia at both times has increased significantly overall (12% in 1977–79 to 24% in 1995–96 on NETS arrival, 4%-19%, respectively at end of transfer) and for all weight groups except infants less than 1000g. The range of abnormal temperatures has not substantially changed over time.
Conclusion: There has been significant improvement in avoidance of hypothermia and cold stress amongst infants requiring emergency neonatal transport from 1977 to 1996. However, in order to improve the number of infants transferred who achieve a temperature in the normal range the need to avoid hyperthermia is highlighted. Infants who require incubator care for optimal medical management require continual monitoring of temperature and review of environmental conditions to optimise the conditions both prior to and during transport.     

Removal of Porcelain Veneers Aided by a Fluorescing Luting Cement

Purpose: Porcelain veneers are a safe and effective treatment modality for selected teeth that have poor esthetics. However, removal of porcelain veneers that have failed may be time‐consuming and involve considerable removal of sound tooth structure adjacent to the veneer. The aim of this study was to evaluate a novel method of porcelain laminate veneer removal by incorporating a fluorescent dye into the luting cement that allows the practitioner to visualize the cement on the tooth and remove the veneer without causing residual damage to the adjacent tooth substance. Materials and Methods: Porcelain veneers were luted on extracted teeth with a luting cement modified with a fluorescing agent. Faculty teaching staff and final year dental undergraduates were asked to remove the veneers with the aid of a curing light to render the luting cement visible by fluorescing. They were then asked to compare the removal of comparable veneers without this visual aid and to complete a standard questionnaire. The depth of cure of the conventional and modified cements was measured using a penetrometer. Results: Results of the questionnaire indicated that the operators found removing the veneer cemented with the modified (fluorescing) cement considerably easier than removing the veneer cemented with the conventional cement. Microscopy indicated that more damage was caused to the underlying tooth during removal of conventionally cemented veneers. The incorporation of the dye into the cement reduced the depth of cure from 4.238 mm (SD = 0.025) to 3.761 mm (SD = 0.096). CLINICAL SIGNIFICANCE The fluorescent cement was considered to be superior to conventional cements in its ease of visibility, and as a consequence, veneers cemented with the fluorescing cement are easier to remove. The fluorescing dye significantly reduced the depth of cure, but this may not be clinically significant, because of the small thickness of cement employed when luting adhesive restorations. The use of such fluorescing materials may not be restricted to a luting cement for veneers but may also be incorporated into bases and lining materials so they can be visualized on removal of tooth‐colored restorations, to prevent further tooth destruction.     

Role of parvovirus B19 infection in childhood idiopathic thrombocytopenic purpura

Although parvovirus B19 exhibits a strong tissue-tropism for erythroid progenitor cells leading to anaemia, several case reports indicate that parvovirus B19 infection may also cause the development of thrombocytopenia. Despite recent studies, the frequency and clinical relevance of this association have remained questionable. Consequently, and in view of the paucity of evidence regarding a viral aetiology for idiopathic thrombocytopenic purpura (ITP), we examined the role of parvovirus B19 in 47 children with newly diagnosed ITP. Specific viral DNA indicating a current or recent parvovirus B19 infection was demonstrated in 6 of 47 patients (13%) employing the polymerase chain reaction technique. Our study suggests that children with ITP and associated parvovirus B19 infection are characterized by acute onset of profound thrombocytopenia. Among the parvovirus B19 positive children, duration of disease was brief in three children treated with immunoglobulin but chronic in the remaining three patients given high-dose steroids. Prospective studies are needed to confirm these initial observations. This virus should be considered as a possible aetiologic agent in some children with ITP.     

Percutaneous transluminal angioplasty of infrapopliteal vessels: preliminary results and technical considerations

Infrapopliteal balloon angioplasty was performed in 11 patients facing reconstructive surgery for limb salvage. Twelve separate sessions of angioplasty were performed, during which 15 of 16 diseased tibial runoff vessels were successfully dilated. Three complications occurred during percutaneous transluminal angioplasty (PTA). One was related to the concomitant use of a thrombolytic agent to open a femoropopliteal bypass graft and not related to the angioplasty itself. No limbs were lost as a result of complications. The procedure was a technical success in nine of 12 cases (75%) and an initial clinical success in eight of the nine that were technically successful (89%). Follow-up ranged from 1 to 22 months. Six of the nine cases (67%) remained clinically successful during this period. Preliminary results suggest that infrapopliteal PTA is a safe and effective alternative to surgical reconstruction in selected patients.     

In utero gene transfer and expression: a sheep transplantation model

Retroviral-mediated gene transfer was used to insert a Neo R gene into fetal sheep hematopoietic cells obtained by exchange transfusion from lambs in utero. After gene transfer the cells were returned to the donor fetus. The lambs were examined after birth for the presence of a functioning Neo R gene. Of ten analyzable animals, six were positive for G418 resistant progenitor cells (CFU-Mix, CFU-C, BFU-E, CFU-E). Two animals were studied for extended periods of time: 8 and 24 months. Each has demonstrated a pattern wherein positive periods are interspersed with times when there were no detectable G418-resistant cells. We conclude that retroviral-mediated gene transfer can be used to insert genes into early progenitor cells of fetal sheep in utero and that the animals can continue to demonstrate blood cells expressing the gene for more than 2 years after birth. This is a US government work. There are no restrictions on its use.