Crystalloids, colloids and kids: a review of paediatric burns in intensive care

This is a retrospective review of all burns patients admitted to a paediatric intensive care unit (PICU) over a 7 year period. Resuscitation fluid therapy and clinical course are presented. Ninety-eight new burns victims were admitted with a mortality rate of 10.2%, all in burns of greater than 25% body surface area (BSA). The incidence of ARDS was 20%, with an 18% mortality rate. Of 85 patients with burns greater than 5% BSA, 33 received the hospital-recommended colloid-based resuscitation formula, 46 received a combination of crystalloids and colloids and in 6 patients the resuscitation regimen was not able to be determined. The aetiology, age distribution, sex ratio, severity of burns and length of stay in hospital did not alter significantly over the study period. The number of burns admissions to PICU increased, as did their duration of intubation and ICU stay. The hospital-recommended resuscitation formula consistently underestimated the fluid volume required for adequate resuscitation. No statistically significant difference in adverse effects was found between the resuscitation groups. This study is unable to recommend a definitive approach to the fluid resuscitation of burns shock in paediatrics and the best approach is one of meticulous fluid resuscitation titrated on clinical effect.     

Focal reduction of villous blood flow in early indomethacin enteropathy: a dynamic vascular study in the rat

Background—Oral indomethacin causes villousshortening, microvascular damage, and distortion, which might inducemucosal ischaemia and necrosis.
Aims—In order to determine the early events inindomethacin induced jejunal injury we examined the temporal relationsbetween morphological damage and changes in villous blood flowfollowing indomethacin.
Methods—In anaesthetised rats, mid jejunal villiwere exteriorised in a chamber and observed by fluorescence microscopy.Blood flow in surface capillaries was calculated from velocities and diameters. Indomethacin was applied by both luminal and intravenous routes for 90 minutes, after which the animal was perfusion fixed andthe villi were processed for histological examination. Control animalsreceived intravenous or luminal bicarbonate (1.25%).
Results—Blood flow slowed in individual villi at20 minutes, and progressed to complete stasis (in another group) by 45 minutes. Histological examination at 20 minutes revealed microvascular distortion, but no villous shortening: crypt depth:villous height ratios were 0.356 (0.02) in test and 0.386 (0.01) in surrounding villi(p>0.5). At stasis, the villi under study showed epithelial clumpingand were shortened: crypt depth:villous height ratios were 0.92 (0.2)in test and 0.42 (0.06) in surrounding villi (p<0.02). Vehicle alonehad no effect on either blood flow or histology.
Conclusions—Focal slowing of villous blood flowand microvascular distortion precede villus shortening and epithelialdisruption, and indicate that damage to surface microvasculature is anearly event in indomethacin induced mucosal injury in this model.

Keywords:indomethacin; jejunum; villi; microcirculation; endothelium; microthrombi

     

Syndrome of Inappropriate Antidiuresis in Ovarian Serous Carcinoma with Neuroendocrine Differentiation

A 58-year-old postmenopausal woman with primary ovarian serous carcinoma presented with the syndrome of inappropriate antidiuresis (SIAD). Preoperative workup showed serum sodium level of 110 mEq/liter and antidiuretic hormone level of 3.3 pg/ml. The serum and urine osmolarity were 239 and 371, respectively. Antidiuretic hormone was demonstrated in tumor cells by immunohistochemistry. To the best of the authors’ knowledge, this represents the first case of SIAD due to primary ovarian tumor.     

Thiol Reduction of 3′-Azidothymidine to 3′-Aminothymidine: Kinetics and Biomedical Implications

The ability of thiols to reduce 3-azidothymidine (AZT) to 3-aminothymidine has been investigated. Incubation with glutathione, dithiothreitol (DTT), or mercaptoethanol at pH 7.2 and 37°C leads to quantitative reduction of the azido moiety to an amine. The reaction is first order in AZT and first order in reducing agent (mono- or dithiol). The second-order rate constants are 2.77 × 10^–3, 6.55 × 10^–5, and 6.35 × 10^–6 M ^–l sec^–1 for the dithiothreitol, glutathione, and mercaptoethanol reductions, respectively. The thiol reduction of alkyl azide to amine under mild conditions is a synthetic method particularly suitable for water-soluble azido compounds that are sensitive to catalytic hydrogenation. The potential for the mono- or dithiol-mediated reduction of alkyl azides under biological conditions must be considered when conducting studies of azido drugs.     

Factors influencing the likelihood of successful decisions to treat dentin caries from bitewing radiographs

The purpose of this study was to describe the role played by the ability to estimate caries depth in successfully deciding to treat dentin caries when making use of bitewing radiographs as a diagnostic test. A 10% random sample (n = 444) of Dutch dental practitioners was sent a two-wave questionnaire concerning radiographic caries diagnosis and restorative treatment decision making. The second wave consisted of simulated bitewing radiographs of 105 tooth surfaces with and without dentin caries according to two measuring standards: (a) a micro-radiographic "gold" standard and (b) a norm of expert observers. The dentists were asked to diagnose caries at 4 depths of penetration using a 5-point certainty scoring system to measure diagnostic ability; and to make a treatment decision for each surface. The overall response was 61% (273). A regression analysis was carried out using the chance per dentist of correctly deciding to treat dentin caries as the dependent variable. The degree of agreement with the experts' diagnosis of radiographic caries depth was used to create variables measuring diagnostic ability. Five significant (P less than 0.05) variables explained 60% (R2 = 0.60) of the variation in decision making. The best diagnostic ability variable explained 47% of the variation while the treatment criterion reportedly used explained 3%. We conclude that the ability of practitioners to interpret radiographs plays a major role in treatment decision making and that their reported treatment decision making criteria should not be taken at face value.     

Functional compartmentalization of energy production in neural tissue

Previous work in our laboratory has shown that neural trauma results in a disparity between oxidative and glycolytic rates. In non-neural tissue, glycolysis and oxidative phosphorylation have been shown to work independently of one another, a phenomenon known as "energy compartmentalization". We believe that functional compartmentalization of energy production may also occur in the brain with glycolysis providing energy for membrane bound ionic pumps. Spreading depression, induced in rodent brain by topical KCl application, results in K+ shifts. The restoration of K+ gradients is accomplished by energy dependent Na(+)-K+ pumps. If these pumps depend upon glycolysis, blocking glycolysis should prevent reconstitution of normal [K+]e levels. The present series of experiments were designed to suggest that energy compartmentalization may also exist in brain, and that glycolytic energy production is preferentially used by Na(+)-K+ pumps to maintain normal ionic homeostasis by observing the dynamics of spreading depression induced K+ shifts before and after glycolytic blockade. Spreading depression was associated with increased K+ (48.6 +/- 16.6 mM over control) that normalized within 2.9 +/- 0.3 minutes. Following superfusion with a glycolytic blocking agent, spreading depression produced similar increases in [K+]e (40.6 +/- 12.0 mM over control) but time for reconstitution of the normal [K+]e was 400% longer than controls (2.9 +/- 0.3 to 14.9 +/- 2.1 minutes, P less than 0.001). Time required for recovery of EEG was identical pre- and post-blockade. We believe these data suggest that energy compartmentalization may exist in neural tissue and that glycolytic pathways of energy production are functionally tied to membrane Na(+)-K+ pumps.(ABSTRACT TRUNCATED AT 250 WORDS)     

Family management of schizophrenia: A comparison of behavioral and supportive family treatment

This paper reports a comparison of behavioral and supportive family treatment for family management of schizophrenia. The family project applied two psychoeducational approaches to a highly treatment resistant population of young adults afflicted with chronic mental illness. The study compares and contrasts the effects of behavioral and supportive family management programs on clinical outcomes. Clinical improvements were associated with both family interventions. Discussion is provided on the relevance of this work to the growing body of evidence concerning the efficacy of psychoeducational family intervention for the management of schizophrenia.     

Diagnosis of pneumococcal pneumonia by psaA PCR analysis of lung aspirates from adult patients in Kenya

psaA is the gene encoding pneumococcal surface adhesin A (PsaA), a 37-kDa protein expressed on the surface of Streptococcus pneumoniae. PCR primers for psaA have been shown to amplify the target DNA sequence in all 90 serotypes of S. pneumoniae and in none of 67 heterologous pathogens and colonizing bacteria of the upper respiratory tract. Pathogenic bacteria identified in lung aspirate specimens cannot normally be dismissed as contaminants or colonizers, which limit the assay specificity of other respiratory tract specimens. psaA PCR analysis was evaluated in 171 lung aspirates from Kenyan adults with acute pneumonia. The limit of detection was one genome equivalent. Sensitivity, estimated in 35 culture-positive lung aspirates, was 0.83 (95% confidence interval, 0.70 to 0.95). psaA PCR analysis extended the number of identifications of S. pneumoniae in lung aspirates from 35 on culture to 61 by both methods. Of 26 new pneumococcal diagnoses, 19 were corroborated by results of blood culture or urine antigen detection. Sequences of the PCR products from 12 positive samples were identical to the psaA target gene fragment. Using an internal control for the PCR, inhibition of psaA PCR was demonstrated in 17% (8 of 47) of false-negative specimens. The results of a control PCR for the human gene beta-actin suggested that false-negative psaA PCR results are attributable to problems of specimen collection, processing, or DNA extraction in 30% of cases (14 of 47). psaA PCR analysis is a sensitive tool for diagnosis of pneumococcal pneumonia in adults.