Starting with a higher dose of inhaled corticosteroids in primary care asthma treatment.

New British guidelines on the treatment of asthma (9) advocate starting with a higher dose of inhaled corticosteroids in newly detected asthma patients. We investigated whether initiating inhaled steroid treatment with a higher dose is clinically more effective than a lower dose in steroid naive patients with asthma. The study had a 13-wk randomized, double-blind, parallel design: 1-mo treatment with 400 microg budesonide twice a day, or 100 microg budesonide twice a day by dry powder inhaler, and follow-up treatment period of 2 mo with 200 microg budesonide once daily for all patients. Forty patients started with 400 microg budesonide twice daily, 44 with 100 microg budesonide twice daily. Mean age was 32 yr, baseline FEV1 value 84% predicted, reversibility 9% from baseline, and mean bronchodilator use 1.6 inhalations/d in the run-in period. After 4 wk of treatment with 400 microg and 100 microg budesonide twice daily mean morning peak expiratory flow (PEF) increased 27 L/min (SD 50), and 38 L/ min (SD 53), respectively (p = 0.30); mean symptom score improved from 1.1 to 0.6 and from 1.1 to 0.5. These effects were maintained in the 2 mo follow-up. This study suggests that starting inhaled corticosteroids at a higher dose is not superior to a lower dose in the treatment of newly detected asthma.

Population differences of fetal biophysical and behavioral characteristics.

Population differences in nonstress test reactivity have been reported with a threefold increase in the likelihood of nonreactive nonstress tests observed in black fetuses as compared with white fetuses. We analyzed fetal behavioral states and fetal heart rates in 14 black and 15 white fetuses at term to explain this observed difference in nonstress test reactivity. Two-hour Doppler and real-time ultrasonographic examination of each patient revealed no differences in percent time spent in the four behavioral states between the two populations. A 9.5 beats/min difference between black and white fetuses was found. The higher baseline heart rate of the black fetuses persisted in each behavioral state and may affect nonstress test reactivity because of rate-dependent decreases in short-term variability and rate-dependent limitations of maximal acceleration amplitude.

Vibro-acoustic stimulation of the human fetus: effect on behavioural state organization.

Vibro-acoustic stimulation of the human fetus in being increasingly performed both antenatally and during labour, to differentiate between poor and good fetal health in cases of flat or otherwise suspect fetal heart rate patterns. In a controlled study we investigated the effect of the electronic artificial larynx (EAL) on fetal behavioural state organization. In 10 healthy women with normal pregnancies of 38-40 weeks of gestation, recordings of fetal heart rate, body movements and eye movements, with a duration of 120-210 min, were carried out during two consecutive days. In each fetus, 3-4 episodes of state 1F and consecutive state 2F were studied, one of which served as a control observation. EAL stimulation during state 1F was associated with excessive fetal movements and with a state change in 7 out of 9 observations (four times into 2F; three times into 4F). Stimulation during state 2F was associated with a change into 4F in four of the nine observations. On days with EAL stimulation the fetuses spent more time in state 4F or in an episode not classifiable (because of an atypical FHR pattern with tachycardia and small accelerations) than control fetuses (21% vs. 3% of time). Disorganized states or periods of state 4F sometimes lasted for more than 1 h following the stimulation. It is concluded that stimulation with the EAL induces excessive fetal movements, a prolonged tachycardia, non-physiological state changes and a disorganisation and change in the distribution of fetal behavioural states. Until more is known regarding the safety and risks of vibro-acoustic stimulation, it should not be used in a routine clinical setting.

Responses of pigeon vestibular nerve fibers to sound and vibration with audiofrequencies.

Single unit recordings were made from the nerve branch innervating the crista in the horizontal semicircular canal of a pigeon. The vestibular organ was either stimulated with sound through the ear canal or with a vibrator in contact with the membraneous ampulla roof. Units responding to sound or vibration showed tuning with a best frequency of approximately 0.7 kHz. The average low-frequency slope of the tuning curves is--16 dB/oct; the average high-frequency slope 20 dB/oct. The threshold amplitude for vibrator stimulation is 30 nm. This value comes close to the calculated threshold value for cupula deflection in the human semicircular canal.