Taylor DM, O'Toole KS, Auble TE, Ryan CM, Sherman DR, et al.
Pharmacotherapy. Date of publication 2000 Sep 1;volume 20(9):1045-50.
1. Pharmacotherapy. 2000 Sep;20(9):1045-50.
The psychometric and cardiac effects of pseudoephedrine in the hyperbaric
environment.
Taylor DM(1), O'Toole KS, Auble TE, Ryan CM, Sherman DR.
Author information:
(1)Department of Emergency Medicine, University of Pittsburgh, Pennsylvania, USA.
STUDY OBJECTIVES: To examine the psychometric and cardiac effects of
pseudoephedrine at 1 and 3 atmospheres (atm) of pressure (0 and 66 feet of sea
water, respectively), and to make recommendations about the agent's safety in the
diving environment.
DESIGN: Double-blind, placebo-controlled, crossover study.
SETTING: Monoplace hyperbaric chamber of a university hospital.
SUBJECTS: Thirty active divers (mean age 38 yrs).
INTERVENTION: A bank of seven tests was used to assess cognitive function during
four different simulated dive combinations: placebo-1 atm, placebo3 atm,
pseudoephedrine-1 atm, and pseudoephedrine-3 atm.
MEASUREMENTS AND MAIN RESULTS: Heart rate and cardiac rhythm were recorded during
all dives. Repeated-measures analysis of variance was used to analyze the effects
of pseudoephedrine, depth, and drug-depth interaction. No significant,
independent effects of pseudoephedrine were seen on any of the seven psychometric
test scores (p>0.05), although the drug tended to increase anxiety scores
(p=0.092). Depth resulted in a significant increase in anxiety scores (p=0.021)
and a significant decrease in verbal fluency test scores (p=0.041); it had no
significant effects on the other five psychometric tests (p>0.05).
Pseudoephedrine caused a significant increase (p=0.036) in mean heart rate, and
depth caused a significant decrease (p=0.013). Neither pseudoephedrine nor depth
affected cardiac rhythm.
CONCLUSION: Pseudoephedrine does not cause significant alterations in
psychometric performance at 3 atm of pressure that might increase the risk of
diving. Depth causes significant adverse effects on anxiety levels and semantic
memory at 3 atm. Pseudoephedrine and depth have significant but opposite effects
on heart rate; although, these effects are unlikely to be clinically significant
during diving. It is unlikely that pseudoephedrine adds significant risk to the
diver.
PMID: 10999495 [Indexed for MEDLINE]
