Oxytocin is unequally distributed in a bag of normal saline--true or false?

Oxytocin infusion used in labour can sometimes be left hung on the stand for many hours. There has been no study to determine if oxytocin is equally distributed throughout the infusion bag and if the distribution stays the same with time. We postulated that there may be settling of the molecules such that oxytocin concentrates at the bottom of the infusion bag. Eight infusion bags were prepared by mixing 10 IU of oxytocin in 1 litre of normal saline. The infusion bags were hung on infusion stands for 8 hours after which 10 samples of 100 mls of the solution from each bag were taken in different containers and the concentration of oxytocin calculated using oxytocin specific Enzyme Immunoassay (EIA) in the different samples. No statistically significant correlation between the oxytocin concentration and the sample number was observed (p-value = 0.738). There was no obvious relationship between oxytocin concentration and the sample number in each bag. There was no evidence to suggest that a linear oxytocin concentration gradient develops in a bag of normal saline over an 8-hour period. In fact the distribution appears to be random and unequal.

Diagnostic and therapeutic dilemma associated with atypical glandular cells on liquid-based cervical cytology.

BACKGROUND: In 2008, the management of women in Ireland with atypical glandular cells changed to immediate referral to colposcopy. The optimal management of these women is unclear. A balance between the detection of occult disease and overtreatment is required. METHODS: Our study aim was to document the experience of this policy at the National Maternity Hospital, Dublin. Information from the computerized data management system was analysed with the statistical package SPSS. RESULTS: In 2009, 156 women attended colposcopy following a single atypical glandular cell diagnosis on liquid-based cytology. The mean age was 41 years. Thirty (19.2%) women had abnormal vaginal bleeding, 31 (19.9%) were smokers and 34 (21.8%) had received previous treatment. The colposcopy was satisfactory in 125 (80.1%) and unsatisfactory in 31 (19.9%). Cervical histology was available for 146 (93.6%) women: 57 excisional procedures and 89 diagnostic biopsies. Abnormal histology was detected in 46 women (31.5%). Four women (2.7%) had invasive cancer, five (3.4%) had adenocarcinoma in situ, 21 (14.4%) had cervical intraepithelial neoplasia (CIN) grade 2 or 3 and 16 (11.0%) had CIN1. No abnormality was detected in 100 women (68.5%), including 35 (61.4%) of those who had undergone excisional procedures. The colposcopic impression in this group was unsatisfactory in 10 women (28.6%), glandular abnormalities in six (17.1%), high- and low-grade changes in 12 (34.2%) and six (17.1%) women, respectively, and normal in one (2.9%). The findings were essentially negative in the remaining 10 women: overall, 30 (19.2%) of the 156 women referred to colposcopy had at least CIN2. CONCLUSION: This study confirmed significant levels of high-grade disease in women referred to colposcopy with atypical glandular cells on cytology. Concerns about undetected endocervical disease resulted in high levels of negative excisional biopsies. Alternative strategies, including endometrial sampling, human papillomavirus testing and discussion at clinicopathological meeting, should be considered.

Evaluation of the efficacy of nebulised lignocaine as adjunctive local anaesthesia for fibreoptic bronchoscopy: a randomised, placebo-controlled study.

Optimisation of topical anaesthesia for flexible fibreoptic bronchoscopy (FOB) is becoming increasingly important as a wider range of more complex, and thereby more prolonged, interventional endoscopic procedures are becoming available. Lignocaine is the most commonly used topical anaesthetic agent for bronchoscopy, but there is variability in current practice as to its optimum mode of administration. In this prospective, randomised, placebo-controlled, blinded study, we examine whether there was enhanced effectiveness of additional nebulised lignocaine as compared to our current regime utilising two visual analogue scales as markers of efficacy. Treatment groups were matched in terms of age (p = 0.39), gender, concomitant sedation (p = 0.51 midazolam; p = 0.12 fentanyl) and dose of background administered lignocaine (290 mg). We found no significant additional differences between any of the treatment groups in terms of general ease of procedure (p = 0.09) or in cough severity (p = 0.12). We conclude that this study does not support the hypothesis that additional nebulised lignocaine confers any additional benefit to the ease of procedure or cough severity in patients undergoing fibreoptic bronchoscopy. We suggest that preparation regimes for bronchoscopic examinations need optimization.

The comparison of rapid bioassays for the assessment of urban groundwater quality.

Groundwater is a complex mixture of chemicals that is naturally variable. Current legislation in the UK requires that groundwater quality and the degree of contamination are assessed using chemical methods. Such methods do not consider the synergistic or antagonistic interactions that may affect the bioavailability and toxicity of pollutants in the environment. Bioassays are a method for assessing the toxic impact of whole groundwater samples on the environment. Three rapid bioassays, Eclox, Microtox and ToxAlert, and a Daphnia magna 48-h immobilisation test were used to assess groundwater quality from sites with a wide range of historical uses. Eclox responses indicated that the test was very sensitive to changes in groundwater chemistry; 77% of the results had a percentage inhibition greater than 90%. ToxAlert, although suitable for monitoring changes in water quality under laboratory conditions, produced highly variable results due to fluctuations in temperature and the chemical composition of the samples. Microtox produced replicable results that correlated with those from D. magna tests.