Nitrous oxide for the treatment of acute migraine headache.

The objective of this study was to determine the efficacy of nitrous oxide in the therapy of acute migraine symptoms in emergency department (ED) patients. This was a prospective, randomized, double blind study of patients presenting to an ED. All eligible patients had a prior diagnosis and symptoms consistent with migraine headache and a normal neurological examination. Patients were randomized to receive either 50% nitrous oxide and 50% oxygen or 100% oxygen over 20 minutes. All patients completed a visual analog pain scale before and immediately after intervention. Initial pain scores and change in pain scores between the two groups were compared. There were 22 patients enrolled, 10 in the nitrous oxide group and 12 in the oxygen group. The groups were similar in age, gender, duration of headache, and initial pain scores. Pain scores decreased significantly in the nitrous oxide group (median change, 69 to 21 mm, P = .02). The oxygen group did not show significant change in pain scores (median change, 78.5 to 72, P = .09). Eighty percent of patients receiving nitrous oxide required no rescue medication at the completion of the intervention, compared with 17% of those receiving 100% oxygen (P = .008). Twenty minutes after termination of intervention, 60% of patients who had received nitrous oxide still required no rescue medication, compared with 8% of those who had received 100% oxygen (P = .02). Nitrous oxide shows efficacy in ED short-term treatment of acute migraine headache.

"Refuses to walk" as an ED presentation of acute childhood leukemia.

New onset of childhood acute leukemia may present to the emergency department in a variety of ways. This report describes the case of a 3-year-old boy who refused to walk and had minimal physical findings, normal X-rays, and nearly normal lab screening results. His white blood cell count differential led to the diagnosis of acute leukemia. The presentation and evaluation of acute leukemia in children is reviewed. Emergency physicians must be prepared to rule out malignancy in the child who refuses to walk when other more common causes, such as infection and trauma, seem unlikely.

Physiological and psychological responses to exercise with an induced attentional focus.

In this study techniques were employed to induce exercising subjects to focus attention on themselves or on an external event. A total of 20 adult subjects (10 men and 10 women) were familiarized with a treadmill exercise protocol and then on two subsequent occasions performed submaximal exercise followed by a run to exhaustion under attentional conditions of self-focus (watching themselves in a mirror while listening to their breathing) and external focus (watching and listening to a movie). The order of focus conditions was counterbalanced among subjects. Analysis of postexperimental responses from subjects indicated that the procedures used to induce each type of attentional focus were successful. However, physiological and psychological responses in the two focus conditions were not always uniform for men and women, particularly during light work when men tended to have higher heart rates and significantly lower Rated Perceived Exertion while women had lower heart rates and higher Rated Perceived Exertion under self-focused conditions than under externally focused conditions. Possible explanations for the incongruence of physiological and psychological responses of men and women to the two types of attentional focus are discussed.