Search

Background: Conducted electrical weapons (CEWs) are used by law enforcement to subdue combative subjects. Occasionally, subjects will die after a CEW has been used on them. It is theorized that CEWs may contribute to these deaths by impairing respiration. Objectives: To examine the respiratory effects of CEWs. Methods: Human volunteers received a 15-second application of electrical current from a CEW while wearing a respiratory measurement device. Common respiratory parameters were collected before, during, and after exposure. Health histories and demographic information were also collected. Results: Fifty-two subjects were analyzed. Thirty-four underwent a 15-second continuous exposure, and 18 underwent three 5-second burst exposures. In the continuous application group, the baseline mean tidal volume of 1.1 L increased to 1.8 L during application, the baseline end-tidal CO2 level went from 40.5 mm Hg to 37.3 mm Hg after exposure, the baseline end-tidal oxygen level went from 118.7 mm Hg to 121.3 mm Hg after exposure, and the baseline respiratory rate went from 15.9 breaths/min to 16.4 breaths/min after exposure. In the 5-second burst group, the baseline mean tidal volume increased to 1.85 L during application, the baseline end-tidal CO2 level went from 40.9 mm Hg to 39.1 mm Hg after exposure, the baseline end-tidal oxygen level went from 123.1 mm Hg to 127.0 mm Hg after exposure, and the baseline respiratory rate went from 13.8 breaths/min to 14.6 breaths/min after exposure. Conclusions: Prolonged CEW application did not impair respiratory parameters in this population of volunteers. Further study is recommended to validate these findings in other populations.

The external intercostal muscles in humans show marked regional differences in respiratory effect, and this implies that their action on the lung during breathing is primarily determined by the spatial distribution of neural drive among them. To assess this distribution, monopolar electrodes were implanted under ultrasound guidance in different muscle areas in six healthy individuals and electromyographic recordings were made during resting breathing. The muscles in the dorsal portion of the third and fifth interspace showed phasic inspiratory activity with each breath in every subject. However, the muscle in the ventral portion of the third interspace showed inspiratory activity in only three subjects, and the muscle in the dorsal portion of the seventh interspace was almost invariably silent. Also, activity in the ventral portion of the third interspace, when present, and activity in the dorsal portion of the fifth interspace were delayed relative to the onset of activity in the dorsal portion of the third interspace. In addition, the discharge frequency of the motor units identified in the dorsal portion of the third interspace averaged (mean +/- S.E.M.) 11.9 +/- 0.3 Hz and was significantly greater than the discharge frequency of the motor units in both the ventral portion of the third interspace (6.0 +/- 0.5 Hz) and the dorsal portion of the fifth interspace (6.7 +/- 0.4 Hz). The muscle in the dorsal portion of the third interspace started firing simultaneously with the parasternal intercostal in the same interspace, and the discharge frequency of its motor units was even significantly greater (11.4 +/- 0.3 vs. 8.9 +/- 0.2 Hz). These observations indicate that the distribution of neural inspiratory drive to the external intercostals in humans takes place along dorsoventral and rostrocaudal gradients and mirrors the spatial distribution of inspiratory mechanical advantage.

Keywords: occupational; carpenter; construction industry; allergic contact dermatitis; chromate; epoxy; obeche; jacaranda; woods; respiratory effect

A 17-year-old female presented because of acute erythema of the hands, oedema of the eyelids, dyspnea and cough occurring 2 months previously. Remission had rapidly been obtained with systemic corticosteroid and antihistamine. The patient had experienced these symptoms after throwing raw rice during a wedding, though she had always eaten cooked rice without problems. Further enquiry revealed a generalized acute urticaria 6 years before, after eating polenta, an Italian food made with maize flour.

2 patients with acute allergic contact dermatitis from 3-(aminomethyl)-pyridyl salicylate are described. Both patients were females with histories of urticaria and showed cross-sensitization to substances of the para group. Clinical manifestations included eczema, angioedema and respiratory effects. In 1 patient, airborne elicitation was suspected. A lymphocyte transformation test confirmed the allergy, with an extremely high response index. 35 normal controls were negative.

Radial oxygen losses (ROL) from the roots of intact rice plants were assayed by the cylindrical Pt electrode technique. At 23°C losses from roots grown in waterlogged soil proved to be about double those from non-waterlogged plants. Cooling which lowers respiratory activity led to increased ROL and it was estimated that at 23°C respiratory activity had been reducing oxygen loss by 8 to 10 10–8g O2 cm–2 root surface min–1 (c. 50 %) in the non waterlogged, and by 4.5 to 5.5 10–8g O2 cm–2 min–1 (2C–30 %) in the waterlogged roots. Lacunae formation occurred nearer to the apex and was eventually more extensive in the waterlogged roots while the presence of more intact and presumably functional tissue in the non-waterlogged roots coincides with the greater respiratory effect noted. Estimated flux rates at 23°C (respiration inactive) were respectively 15–17 × 10–8g O2 cm–2 min–1 (non-waterlogged) and 20–23 × 10–8g O2 cm–2 min–1 (waterlogged). A major part of this difference can probably be accounted for directly by the differences in root porosity, and Meakiness' superimposed upon lower porosity in the non-waterlogged plants may account for the remainder. ROL was also examined in relation to distance from the apex. With respiratory activity lowered by cooling, two patterns of oxygen loss were detected. Pattern I was a property of younger roots of length between 5–9 cm, while pattern 2 was found in longer roots 11–16 cm bearing numerous emergent laterals. In both, ROL fell rapidly towards the base and at 4–5 cm approached zero in pattern 1 and near zero to about 16% of the maximum in pattern 2. The rapid drop in oxygen loss in both patterns which indicates a concomitant decrease in root wall permeability was associated with the appearance of cortical lacunae at 2–3 cm from the apex. In pattern 2 a rise in ROL began at 5–6 cm from the apex. The presence of lateral root initials in both the pericycle and unbroken segments of cortex was associated with maintained permeability in this pattern as well as with the basal increase in ROL. With a 3-electrode system placed around the apical 3 cm regions of waterlogged roots, it was found that ROL was substantially affected by respiratory activity at 0.5 cm, a little less so at 1.7 cm, but much less or not at all at 3 cm from the apex. The drop in respiratory effect parallelled the formation of cortical lacunae.