MinervaBMJ 2006; 332 doi: https://doi.org/10.1136/bmj.332.7538.432 (Published 16 February 2006) Cite this as: BMJ 2006;332:432
A Nottingham team hoped to find a significant reduction in falls after second eye cataract surgery among elderly women. However, their randomised controlled trial allocated patients to fast-track or routine surgery, and an unexpected and dramatic reduction in waiting times meant they had to stop the study early on ethical grounds. The number of patients included in the final analysis was too small to analyse the impact of second eye surgery on falls, but it did improve visual disability and confidence (Age and Ageing 2006;35: 66-71).
It's not just a question of which design is best, when it comes to the tools of the trade. A survey of four face masks used for bag-mask ventilation revealed a great variation in performance and satisfaction between designs and the anaesthetists testing them out. Rather than identifying the “best buy,” the authors suggest a range of masks be available for emergency use (European Journal of Anaesthesiology 2006;23: 169-72).
Modafinil has recently been approved for the treatment of sleep disorders in shift workers, so what better group of people to test it on than shift working emergency physicians? Unfortunately, while the drug increased some aspects of cognitive function and subjectively improved the doctors' ability to attend handover sessions after their shift, it also made it more difficult for them to fall asleep when the opportunity for sleep arose (Academic Emergency Medicine 2006;13: 158-65).
The doctor in a training video asked, “How can I help you?” The patient said, “I'm not sure if you really can help me… I've seen lots of specialists and none of them have managed to help me so far. You see I keep having these funny turns.” Asked to identify her presenting complaint, all 10 junior doctors watching the video incorrectly wrote, “Funny turns.” But, when asked what she actually wanted, the patient replied, “a referral for homoeopathy or acupuncture,” and her response on getting one was almost to cry with relief (QJM 2006;99: 125-6).
People who present late with HIV related symptoms in the United Kingdom tend to be older men who've already become frequent attenders to GPs. Most of these late diagnoses are in people who've acquired the infection heterosexually in the UK and have long term partners. None of the people interviewed in this study had been informed by former or current partners of their HIV status. Apart from reminding primary care doctors to consider HIV infection in apparently low risk individuals, the results indicate a need to develop sensitive practices for partner notification (AIDS Care 2006;18: 133-9).
Minerva often receives pictures of “incidental findings” that have been identified on scans with comments like: “Amazingly enough, it wasn't causing any symptoms.” But what about incidental findings uncovered by brain imaging research? A wide-ranging discussion reported in Science (2006;311: 783-4) reveals that one of the more important debates was whether a doctor competent to read scans and to communicate the results sensitively should be part of all research imaging studies when the principal investigator isn't trained to do so.
More women are delaying child bearing, so it's interesting that university students seem unaware of the age related decline in female fertility (Human Reproduction 2006;21: 558-64). In this survey of 222 female and 179 male students in Sweden, most held positive attitudes towards becoming parents and wanted to have children, but about half the women said they wanted to have children after the age of 35. Both men and women were overly optimistic about women's chances of becoming pregnant in their late 30s.
French fried potatoes are out, whole milk is probably in. That's the verdict of a study that tried to determine if there's a connection between what we eat as young children and the risk of developing breast cancer as adults (International Journal of Cancer 2006;118: 749-54). The data were taken from the “nurses' health studies” and “nurses' mothers' study,” and an obvious source of bias may be the recollection of mothers about what their daughters ate decades earlier.
Some colonic bacteria produce hydrogen sulphide (H2S), which is as toxic as hydrogen cyanide. The bowel's mechanism for safely metabolising H2S is efficient, and a minimal amount appears in the flatus. But what if the mechanism is slow to mature? One theory suggests that if the mechanism for destroying H2S isn't fully functional by the age of 3 months, some H2S may be absorbed, resulting in sudden infant death. The theory could be tested by obtaining colonic tissue from infants who have suddenly died from no apparent cause and evaluating its ability to detoxify H2S (Medical Hypotheses 2006;66; 375-9).
Faster infusion rates are achieved with wider bore intravenous cannulas, but what's the effect of the length of the tube? Complex mathematical calculations based on the Hagen-Poiseuille law predicted an increase of 40% in flow rates if a cannula was shortened by 13 mm, but in practice the maximum observed increase was only 18%, which may not be clinically significant (Injury 2006;37: 41-5). The discrepancy between theory and life, say the investigators, was caused by design-induced turbulence.
Uterine rupture is rare but is significantly linked to a history of caesarean section, particularly if there's been incomplete healing of the uterine incision. The method of suturing may be one factor in the equation. An ultrasound study of uterine scars found that the frequency of incomplete healing was significantly lower in women who had received full thickness suturing compared with those who had been sutured without taking in the endometrial layer (European Journal of Obstetrics & Gynecology and Reproductive Biology 2006;124: 32-6).
Guidance at bmj.com/advice