Ebony is a four-month-old girl who is brought to the ED by her mother at 4.00 pm. Her mother states that the child has had difficulty breathing for two days and has been worse overnight. The child has been coughing and feeding poorly. Her fluid intake has been approximately half that of a normal day and she has had a decrease in the number of wet nappies. She has a moist-sounding cough and no audible wheeze. She is tachypnoeic with a respiratory rate of 60 breaths per minute. Examination of her chest shows mild use of accessory muscles. On auscultation she has an expiratory wheeze. Her skin is pink and she has moist mucous membranes.

Laura is a 10-year-old girl who presents to the ED at 11.00 pm with her older sibling saying that she has had abdominal pain for the past few hours. She indicates that the pain is across the centre of her stomach and paracetamol has not helped. She complains of nausea and says that she has vomited once since the onset of pain. When asked, she states that she has had normal bowel motions. She is able to give her own history while leaning over onto the desk, holding her stomach. Her skin is pink and she is not short of breath.

Graham is a 55-year-old male who presents to the ED accompanied by his partner. He states that he has been 'bleeding from the back passage' since the previous night. He is very anxious about the bleeding and reports that it was 'bright red' in colour and 'filled the toilet bowl' on two occasions. His blood pressure is 155/100; his heart rate is 102 beats per minute; his respiratory rate is 20 breaths per minute

Louisa is a 24-year-old female who presents to the ED with her friend after 'fainting'in the toilet at home. She is complaining of left-sided abdominal pains, which she has had 'on and off' for several months. She previously attended the ED two weeks ago for the same problem. An abdominal ultrasound was performed at that time but identifi ed no abnormalities. She rates her pain as 'six out of ten'. Her heart rate is 82 beats per minute and her respiratory rate is 18 breaths per minute. Her skin is cool and dry. She looks pale and uncomfortable.

A mother presents to the ED at 9.20 pm with her nine-week-old son, Christopher, stating that he has had a fever since 4.00 pm that afternoon. She gave him paracetamol at 5.00 pm. She says that he normally vomits after feeds but has vomited once this evening between feeds. Christopher is breast-fed; he has fed less frequently this evening. Christopher's mother also informs you that he had his first immunisation two days ago. He is in his mother's arms and is crying. He appears slightly pale. His hands are warm but his feet are cold. Capillary refill is about two seconds and he has moist mucous membranes and normal skin turgor. His anterior fontanelle is not bulging