Acute effects of nicotine withdrawal syndrome in pilots during flight.

Background: Pilots who smoke are occasionally obliged to abstain from nicotine intake during flight and may during this period exhibit certain symptoms leading to performance decrement.

Methods: We studied 20 healthy male aviators, who were regular smokers, (mean age 33.7 +/- 1.4 yr) operating military fixed- and rotary-wing aircraft (C-47 Dakota, F-16, A. Bell 205). All pilots were subjected to a 12-h abstinence from cigarette smoking, during which time they performed flight duties. After landing, we studied the intensity of the nicotine withdrawal syndrome, as well as its effect on physiological parameters, psychological functions, and cognitive tasks. This was achieved by the completion of a questionnaire, measurement of BP and heart rate, and the execution of certain computerized performance assessment tests. These tests measure mental arithmetic, visual vigilance, and image free-recall. In a subsequent flight performed under similar conditions, every pilot repeated the procedure without smoking deprivation. Thus, each subject served as his own control. The Wilcoxon non-parametric test was applied for statistical analysis.

Results: The most frequent symptoms reported during nicotine deprivation were nervousness, craving for tobacco, tension-anxiety, fatigue, difficulty in concentration, decrease in alertness, disorders of fine adjustments, prolonged reaction times, anger-irritability, drowsiness, increase in appetite, and impairment of judgement. Systolic BP and heart rate tended to decrease and diastolic BP tended to rise during withdrawal, although the differences were not statistically significant. Finally, all tests recorded an impairment of cognitive functions during abstinence.

Conclusion: Abrupt cessation of smoking may be detrimental to flight safety and the smoking withdrawal syndrome may influence flying parameters.