Starch, gloves and extradural catheters

We have investigated contamination of extradural catheters during normal handling with starch powdered gloves. In the laboratory, extradural catheters were handled in sterile fields with both powdered and non-powdered gloves, simulating preparation for patient insertion. The catheters together with glove samples were then examined using a Zeiss 940 scanning electron microscope. Microscopy of samples revealed starch contamination of the catheters handled with powdered gloves, especially in the side hole areas. We conclude that extradural catheters may be contaminated easily by starch powder from surgical gloves. This powder may then be deposited into the extradural space. The effect of starch in the extradural space is not known but starch is known to cause inflammatory and granulomatous reactions in other parts of the body as well as being directly allergenic. Powder contamination of catheters may be avoided easily by the use of powder-free gloves and we feel that these should be used whenever possible.      

A comprehensive study of smoking in primary school children in Hong Kong: implications for prevention.

STUDY OBJECTIVE: To identify factors associated with smoking behaviour in primary school children in Hong Kong. DESIGN: A cross sectional survey in which both children and parents completed questionnaires. The main outcome measure was the smoking status of the children; and risk factors (knowledge of and attitude to smoking and demographic and socioeconomic background) were identified as predictors of ever/never smoking. SETTING AND SUBJECTS: Altogether 9598 primary school children, aged 8-13 years, and attending 27 schools from two districts in Hong Kong participated. MAIN RESULTS: The prevalence of ever-smoking was 12% (1119)-15% (760) in boys and 7% (359) in girls. It ranged from 3% in 8 year old girls to 52% in 13 year old boys. The factors associated with ever-smoking included the following: being a boy (adjusted odds ratio 2.21; 95% confidence interval 1.89, 2.59), increasing age per year (1.48; 1.40, 1.57), living in Kwai Tsing district (1.29; 1.10, 1.50), having one or more smokers at home (2.07; 1.78, 2.39), and having a father who was not working (1.41; 1.19, 1.67). Children who were ever-smokers had both seen and approved of their friends' smoking (8.79; 5.33, 14.50), had a more positive attitude towards smoking (3.35; 2.21, 5.09), and were more successful in recognising cigarette brand names and logos (1.67; 1.42, 1.96), but they lacked confidence (1.78; 1.32, 2.39). CONCLUSIONS: The influences on child smoking are multifactorial and programmes in Hong Kong are falling to curb them. The control of these risk factors must be incorporated in the smoking prevention policy of Hong Kong and supported by future enforced legislation.     

The structure of wandering in dementia

‘Wandering’ is one of the most troublesome of behavioural problems in dementia. The term ‘wandering’ covers many different types of behaviour. We examined the hypothesis that the different types of wandering behaviour seen in dementia from a scale using data collected on 83 elderly subjects suffering from either Alzheimer's disease or multiinfarct dementia. We reject the scaling hypothesis. Our data suggest that there are three main categories of wandering behaviour, and that one of these categories is usefully divided into four subcategories.     

Neurofibromatosis and insulinoma.

A 45-year-old man with neurofibromatosis presented with recurrent seizures due to hypoglycaemia caused by an insulinoma. The attacks were abolished after the successful removal of the insulinoma. This probably represents another example of the association between neurofibromatosis and a tumour consisting of cells with amine-precursor-uptake and decarboxylation.     

Interactions Between Cytomegalovirus, Human Herpesvirus-6, and the Recurrence of Hepatitis C After Liver Transplantation

Recurrence of hepatitis C (HCV) following liver transplantation is common. Herpesvirus reactivation following transplant may have an immunomodulatory effect resulting in increased HCV replication. We studied whether cytomegalovirus (CMV) and human herpesvirus-6 (HHV-6) may be associated with HCV recurrence and viral load after transplant. We prospectively followed 66 HCV liver-transplant recipients with serial viral load testing for CMV and HHV-6. Infection and viral load were correlated with the development of biopsy-proven HCV recurrence and HCV viral loads. Histologic recurrence of HCV occurred in 41/66 (62.1%) patients. In the primary analysis, CMV infection and disease, and HHV-6 infection were not associated with HCV recurrence. Peak CMV and HHV-6 viral loads were not significantly different in patients with and without recurrence. No correlation was observed between HCV viral loads at 1 and 3 months post-transplant and peak HHV-6 or CMV viral loads. In a subgroup analysis, HHV-6 infection was associated with the development of more severe recurrence (hepatitis and/or fibrosis score > or = 2) (p = 0.01). Also, fibrosis scores at last follow up were higher in patients with CMV disease (1.67 vs. 0.56; p = 0.016) and in patients with HHV-6 infection (1.18 vs. 0.55; p = 0.031). In conclusion, HHV-6 and CMV infection and viral load were not associated with increased overall rates of HCV recurrence or HCV viral load after liver transplantation but may be associated with more severe forms of recurrence.     

Systematic and random errors in compression testing of trabecular bone

We sought to quantify the systematic and random errors associated with-artifacts in the platens compression test for trabecular bone. Our hypothesis was that while errors may depend on anatomic site, they do not depend on apparent density and therefore have substantial random components. Trabecular bone specimens were first tested nondestructively using newly developed accurate protocols and then were tested again using the platens compression test. Percentage differences in modulus between the techniques (bovine) proximal tibia [n = 18] and humerus [n = 17] and human lumbar spine, [n = 9] were in the range of 4-86%. These differences did not depend on anatomic site (p = 0.21) and were only weakly dependent on apparent density and specimen aspect ratio (r² < 0.10). The mean percentage difference in modulus was 32.6% representing the systematic component of the end-artifact error. Neglecting the minor variations explained by density and specimen size (approximately 10%), an upper bound on the random error from end-artifacts in this experiment was taken as the SD of the modulus difference (±18.2%). Based on a synthesis of data taken from this study and from the literature, we concluded that the systematic underestimation error in the platens compression test can be only approximated and is in the range of 20-40%; the substantial random error (±12.5%) confounds correction, particularly when the sample size is small. These errors should be considered when interpreting results from the platens test, and more accurate testing techniques should be used when such errors are not acceptable.