Objective: To determine if peripheral intravenous cannula dead space is taken into account when setting up intravenous infusions (in particular nitrate infusions) in the emergency department. Method: A postal survey of UK emergency departments. Results: Of the 143 (58%) of UK departments who responded, only 15% reported priming the cannula before commencing the nitrate infusion. Conclusions: Knowledge of peripheral intravenous cannula dead space in UK emergency departments is very poor and, as a result, there is probably significant widespread under treatment of patients in severe cardiogenic pulmonary oedema. Departments should amend their treatment guidelines to take account of peripheral cannula dead space I ntravenous infusions and bolus doses of drugs are commonly used in emergency medicine. Whereas bolus drugs are nearly always followed with a flush to eradicate residual drugs in the cannula, the personal experience of both the authors was that the lines used to give nitrate infusions are rarely (if ever) primed with the relevant medication in order to take account of their ''dead space''. A current (at time of writing) national trial (the 3CPO trial) makes no mention in its treatment guidelines of priming the peripheral cannula when setting up a nitrate infusion.1 Indeed, its guidelines suggest commencing an infusion at 0.6 mg/h. If a large peripheral (Orange (14G)) cannula was being used this would mean a delay (presuming an infusion concentration of 1 mg/ml) of up to 30 min before any nitrate enters the circulation. If (perhaps more commonly) a green (18G) cannula was being used there would be still be a delay of approximately 20 min. We designed a questionnaire study to look at the current treatment of left ventricular failure/ cardiogenic pulmonary oedema. As part of that questionnaire we asked if intravenous nitrates were routinely used and if cannulas were routinely primed prior to commencing intravenous nitrate infusions.

concluded cyclizine may be useful if avoidance or prompt reversal of the hypotensive effect of opiate is required. 3 It is also relevant to observe that no data were given for simultaneous administration of cyclizine with opiate, because cyclizine is usually administered simultaneously with opiate, considerable caution is required if the conclusions of this study are to be translated into advice about clinical care. The clinical bottom line begs the question ''if not cyclizine, what should I use?'' We repeated their search strategy but replaced the ''cyclizine'' with ''metoclopramide'' or ''stemetil/prochlorperazine'', revealing no studies of the effects of these two commonly used drugs. A Cochrane study is being undertaken to review other anti-emetics, 4 we suggest that a more appropriate conclusion would be ''There is the possibility of adverse haemodynamic effects of cyclizine in patients with heart failure, and of beneficial effects in patients with opiate induced hypotension; the effects of other known anti-emetics are unknown.''

W e present a case of an unusual cause (pyometrium) for an acute abdomen in a four-month-old infant. A 4-month-old baby presented late one evening to the emergency department having been unwell for the past 2 weeks with a gastroenteritis-type illness. Her diarrhoea and vomiting (which was non-bilious) had settled in the 24 h before her attendance. Her parents said that she had not been herself; her appetite had decreased and she had cried inconsolably just before her attendance. They had noticed that her abdomen was becoming increasingly swollen and this was their main reason for presenting to the emergency department. There was no history of fever. In the 24 h before attendance, she had not vomited but had passed four yellow-coloured stools. Her medical history showed that she was born at 37 weeks' gestation and required admission to the special care baby unit due to being a small size for dates. She was not ventilated whilst in the special care baby unit. She also had a non-troublesome umbilical hernia and had previously had reflux.On initial examination, she was clinically dehydrated, with sunken fontanelle. She had a temperature of 37.9˚C, a pulse rate of 160 beats/min, a capillary refill time of , 2 s, and her saturations were 98% in room air. She was having intermittent bouts of inconsolable crying, alternating with periods of drowsiness. Her abdomen was grossly distended with overlying veins. It was tense and tender on palpation, and minimal bowel sounds were heard. Her chest was clear and heart sounds were normal.Initial emergency room management included an abdominal radiograph (fig 1), intravenous access, routine blood tests, intravenous bolus fluids and an urgent paediatric review. A nasogastric tube was also inserted, and intravenous ceftriaxone and metronidazole were given. The blood results showed mild hyponatraemia (sodium 129), dehydration (urea 11.6, creatinine 85), and a raised white cell count (21.2610 9 /l) and C reactive protein (147 mg/l). The abdominal radiograph (fig 1) showed minimal gas in most parts of the abdomen and no gas on the right side. Seven radio-opaque areas were found on the film. These are ''poppers'' on the infant's clothing and should be ignored.The baby was then transferred urgently to the regional paediatric surgical unit, and the same night was taken to theatre. Laparotomy was carried out and showed a large distended pyometrium, which was drained with a drainage catheter left in situ. Under the same anaesthetic, she had a cystoscopy, which showed a long tubular structure terminating in her bladder. A suprapubic catheter was inserted and contrast studies of the urogenital tract were arranged. The pyometrium was thought to be secondary to congenital malformation of the urogenital tract-in particular, a fistula between the urinary and genital tracts. She was discharged from hospital 10 days later with a drainage catheter in her uterus and a urethral catheter in situ. She re-attended 1 week later for removal of her urinary catheter, and was started on treatment with trimet...