Thursday 1 April 2010

Airflow efficacy of ballpoint pen tubes: a consideration for use in bystander cricothyrotomy

Emerg Med J. 2010 Apr;27(4):317-20
doi: 10.1136/emj.2008.069294

David Owens [1], Ben Greenwood [1], Alistair Galley [1], Alun Tomkinson [2], Sarah Woolley [3]

[1] Princess of Wales Hospital, Bridgend, Wales, UK
[2] University Hospital of Wales, Cardiff, Wales, UK
[3] Bristol Royal Infirmary, Bristol, England, UK

Correspondence to David Owens, Princess of Wales Hospital, Bridgend, Wales CF31 1RQ, UK

Accepted 8 July 2009

Objective

To examine the suitability of commonly available ballpoint pens as a substitute emergency tracheostomy tube.

Methods

Commonly available ballpoint pens were examined and compared against two standard cricothyroidotomy sets. The pens were evaluated for dimensions, speed of construction of a temporary tracheostomy tube and airway resistance with differing flow rates.

Results

Internal diameters of the pens varied considerably. Time taken to construct a temporary tube ranged from 3 to 170 s, and in the majority of pens the airway resistance increased dramatically as the airflow rate increased.

Conclusion

Contrary to popular belief, the majority of ballpoint pens appear unsuitable for use as a substitute tracheostomy tube. In this study only two pens fulfilled the criteria for use: the Baron retractable ballpoint and the BIC soft feel Jumbo.

http://emj.bmj.com/content/27/4/317.abstract

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Are cows more likely to lie down the longer they stand?

Applied Animal Behaviour Science
Volume 124, Issue 1 , Pages 1-10, April 2010

Bert J. Tolkamp, Marie J. Haskell, Fritha M. Langford, David J. Roberts, Colin A. Morgan

Sustainable Livestock Systems and Animal Health Groups, SAC Research, King's Buildings, West Mains Road, Edinburgh EH9 3JG, Scotland, UK

Abstract

Information on (changes in) standing and lying behaviour of cows can be used for oestrus detection, early diagnosis of disorders and to evaluate welfare consequences of changes in housing and management. Data sets on lying and standing behaviour were collected from cows with IceTag™ sensors fitted to the leg. Data were obtained with 10 late-pregnant indoor-housed beef cows (Exp. 1), 19 out-wintered beef cows (Exp. 2) and 44 housed lactating dairy cows that were milked three times daily (Exp. 3). During part of Exp. 1 video footage was recorded to validate the sensor records. Data were analysed with the aims of estimating objective lying and standing bout criteria and to test two hypotheses. These hypotheses were that (i) the probability of cows standing up would increase with the length of time the animal had been lying down and (ii) the probability of cows lying down would increase with the length of time the animal had been standing. A total of 10,814, 39,089 and 9405 lying episodes were recorded by the sensors in Exp. 1–3, respectively. On the basis of log–survivorship plots, frequency distributions of (log-transformed) lying episode lengths and analysis of the correspondence between recorded lying episodes and video footage of lying behaviour, a minimum lying bout criterion of 4min was indicated. Application of this criterion reduced the number of lying episodes by between 62% and 88% in the three experiments, even though this had only minor effects on total estimated lying and standing time (changes between 0.5% and 3.2%). Out-wintered beef cows tended to have fewer but longer lying bouts than the other groups and dairy cows had the shortest total lying time. (11.6, 10.5 and 10.2h/day in Exp. 1–3, respectively). The probability of cows standing up within the next 15min increased (P<0.001) with lying time in all experiments, which was consistent with the first hypothesis. The probability of cows lying down within the next 15min did not significantly increase with standing time. This lack of change in probability was not caused by pooling of data across day and night or across cows with different behavioural strategies. Our second hypothesis was, therefore, refuted because cows were not more likely to lie down the longer they had been standing.

Keywords:
Dairy cow, Beef cow, Lying, Standing, Bout criteria

http://www.appliedanimalbehaviour.com/article/S0168-1591%2810%2900054-7/abstract

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