10.

11.

12.

REFERENCES

Billings, C. E., R. L. Wick, R. J. Gerke, and R. C. Chase: The Effects of
Alcohol on Pilot Performance During Instrument Flight, FAA Office of Aviation
Medicine Report No. FAA~AM-72-4, 1972.

Blackburn, H., H. L. Tayler, N, Okamoto, P. L. Mitchell, P. M. Rautaharju,
and A. C. Kerkhof: Standardization of the Exercise Electrocardiogram: A
Systematic Comparison of Chest Lead Configurations Employed for Monitoring
During Exercise. In Physical Activity and the Heart, M. J. Karvonen and
Barry (Eds.), Springfield, Illinois, C. C. Thomas, pp 101-134, 1966.

Blomqvist, G., B. Saltin, and J. H. Mitchell: Acute Effects of Ethanol

Ingestion on the Response to Submaximal and Maximal Exercise in Man, CIRCULATION,

42:463-470, 1970.

Collins, W. E.: Performance Effects of Alcohol Intoxication and Hangover
at Ground Level and at Simulated Altitude, FAA Office of Aviation Medicine
Report No. FAA~AM-79-26, 1979.

Damkot, D. K., and G. A. Osaga: Survey of Pilot's Attitudes and Opinions
About Drinking and Flying, AVIAT. SPACE & ENVIRON. MED., 49:390-394, 1978.

DuBois, E.: Basal Metabolism in Health and Disease, London, Leat & Ferigea,
1936.

Ekman, G., M. Frankenhaeuser, L. Goldberg, R. Hagdahl, snd A. Myrsten:
Subjective and Objective Effects of Alcohol as Functions of Dosage and
Time, PSYCHOPHARMACOLOGIA, 6:399-409, 1964.

Federal Aviation Administration, Department of Transportation: Federal
Aviation Regulations, Part 91.11, 1971.

Hansen, J. E., and J. R. Claybaugh: Ethanol-Induced Lowering of Arterial
Oxyhemoglobin Saturation During Hypoxia, AVIAT. SPACE & ENVIRON. MED.,
46:1123-1127, 1975.

Higgins, E. A., A. W. Davis, Jr., J. A. Vaughan, G. E, Funkhouser, and
E. M. Galerston: The Effects of Alcohol at Three Simulated Aircraft Cabin
Conditions, FAA Office of Medicine Report No. FAA-AM-68-18, 1968.

Higgins, E. A., J. A. Vaughan, and G. E. Funkhouser: Blood Alcohol
Concentrations as Affected by Combinations of Alcoholic Beverage Doses
and Altitudes, FAA Office of Aviation Medicine Report No. FAA-AM~70-5,
1970.

Hordinsky, J. R.: A New Application of LBNP to Measure Orthostatic
Tolerance Before and After Zero-G Simulation (Water Immersion), Proceed-
ings of the Thirtieth Congress, International Astronautical Federation,
Munich, Federal Republic of Germany, Pergamon Press, New York, pp 1-15,
1979,

17


TABLE IV. Pulse Pressure (PP) and Mean Arterial Pressure (AP)

PP (mmlig) . PP (% of Control)
Ry Ry R3 LBNP R3/R, X100 LBNP/R3 X100
= ! |
x 61.6 | 64.1 | 60.0 | 50.5 97.2 84.5
PI Alcohol
SE 7.0 7.4 7.5 6.5 } 4.5 4.0
x 59.8 | 64.0 | 56.5 | 49.0 95.8 86.3
PI Placebo
SE 7.7 8.1 6.3 6.9 2.7 4.6
x 49.4 | 48.6 | 52.8 | 40.4 106.7 76.9
PII Alcohol *
SE 3.0 3.1 3.6 4.3 3.1 6.9
Xx 52.5 51.8 51.2 49.3 97.0 94.9
PII Placebo
SE 2.7 3.9 3.7 5.0 4.0 3.5
AP (mmlig) AP (% of Control)
Ry Ro R3 _‘LBNP R3/Ry X00 LBNP/R3 x100
x 82.3 | 85.3 7 81.9 | 82.0 | 99.7 100.1
PI Alcohol
SE 1.9 1.3 1.7 2.3 3.1 LL
x 81.5 | 82.6 | 83.1 | 87.0 102.1 104.4
PI Placebo
SE 1.5 1.6 2.0 7.4 2.5 6.6
x 78.5 | 80.0 ' 77.7 72.9 98.9 93.9
PII Alcohol *
SE 2.5 3.4 3.1 3.4 2.5 2.4
x 76.8 | 82.3 | 82.8 | 79.9 107.9 96.6
PIZ Placebo
SE 2.3 3.4 2.5 2.7 1.7 1.6
X = mean SE = Standard error of the mean
AP = Mean arterial pressure, calculated as the value of DBP + 1/3 PP
PI = Phase I experiments at GL only PII = Phase IT experiments at 3,048 m MSL altitude

Ry, Ry, Rz = Periods of resting physiolozical measurements
LBNP = Lover body negative pressure of -40 torr for 2 min
* = Statistical significance at p < 0.05

ql


cardiovascular function and useful consciousness during applied lower body
negative pressure (LBNP); and (iii) perform moderate physical work efficiently
as measured by quantitative shifts in cardiorespiratory funccions during pedai
ergometry.

METHODS

Because LBNP testing had not been conducted at altitude in humans with
substantia] BAC's, a group of six subjects was initially tested (Phase I) at
ground level (GL) (388 m mean sea tevel, MSL). There were no untoward occur—
rences at GL in Phase I; therefore, a second group of 10 subjects (Phase II)
was tested at an aititude of 3,048 m MSL.

Subjects. The participants were paid, healthy male volunteers (25-40
years old) who admitted previous experience in moderate consumption of liquor.
Each subject had to pass a third-class medical examination equivalent to that
required of a private pilot. The qualified subjects signed a standard consent
form after a thorough briefing. Each subject experienced a complete practice
session of the research protocol. For Phase 1, this included a 1-h training
session in our hypobaric chamber at GL. The subject was trained to properly
blow an expired air sample into the apparatus ("Intoxilyzer") which measured
the BAC. He took two timed arithmetic tests {psychomotor performance), he
was subjected to LBNP at -40 torr differential pressure for 2 min as a test
ol orthostatic tolerance, and he carried out pedal ergometry at a load of
50 watts (W) for 4 min. The subject was cisqualisied from further partici-
pation if consciousness was not maintained during LBNP, if his HR exceeded
150 beats per min (bpm) during pedal ergometry, or if his monitored single-
dead electrocardiogram (ECC) manifested evidence of ischemia or arrhythmia
at any time during this session.

Each Phase II subject experienced 2 !-h training session in our hypobaric
chamber at 3,048 m MSL during which he practiced single-breath "intoxilyzerTM
measurements of BAC, took two timed arithmetic tests, and underwent 2 min of
LBNP. After chamber pressure was returned to GL, the subject practiced 4 min
of pedal ergometry at 50 W. Besides the disqualification criteria of Phase I,
the subject was disqualified if his HbO2 fell below 80 percent during altitude
exposure (16). The subjects’ age, height, and weight data ere summarized in
Table I.

Protocols and Variables. Each subject participated in one experiment per
week for 2 consecutive weeks. The protocols for Phases I and ii are outlined
in Table II, Each subject arrived at 1115 when his temperature and health
status were checked. At 1130 he was fed a ham and swiss cheese sandwich and 2
cup of chicken soup in order to avoid alcohol intake on en empty stomach and to
avoid any possible effect of fasting through the midday meal period. After 30
min of resting digestion, the subject took two timed arithmetic tests. Each
test consisted of 20 pages of simple addition and subtraction problems (20 per
page) to be answered true cr false. The subject was instructed to make a check~
mark in the correct answer block provided for each problem. The score equaled
the number of incorrect answers per min of tetal test time. As a separate test
of eye/hand coordination, the subject was asked to make the checkmark within
the appropriate answer block without the checkmark touching any OF the block s

-


Nu
ra

8.

Krutz, R. W. Jr., S. A. Rositano, ané R.
Techniques for Measuring +Gz Tolerance
38:1143-1145, 19

Lategola, M. T., and C. C. Trent: Lower Body Negative Pressure Box for
+Gz Simulatio:. in the Upright Seated Position, AVIAT. SPACE & ENVIRON.
MED., 50:1182-1184, 1979.

Luft, U. C., L. G. M
Physiological Studies i
Report, NASA, Contract:

Specialized
ual Research

McFarland, R. A.: Human Factors in +
New York, p 159, 1953.

Ryan, L. C., ana S. BR
i+. Civi. Aircraft Ace
FAA~AM-~80-4, 1980.

Role of Alcchoi as 2 Factor
Mecicine Report Ne.

Saunders, N. A., A. C.
Accuracy and Practicabi
AM. REV. RESPIR. DIS.,

etry
he Assessment of Arterial Oxygenation,

S$, and A. S. Rebuck: Ear Ox
t
7 1976,

Snedecor, G. W.: Statist
4th Ed., pp 54-88, 1956.

Methods, Iowa College Press, Ames, Towa,

Stegemann, J.: Beziehun
CARDIOLOGY, 61(Suppi. 1)

rainingzustand und Orthostasetoleranz,

376 .

Wallgren, H., and H. Barry, ITI: Actions of Aicohol, volume I, Biochemical,
Physiological, and Psychological Aspects, Elsevier Publishing Company,
Amsterdam-London-New York, 1970.



Physical Work Tolerance. The interpolated mean Cc during pedal ergometry
was about 80 mg percent. As shown in Table VI, ali ihe variables in the alco-
hol condition of Phases I and II experiments changed in the direction of lessened
ergometric efficiency as compared to corresponding placebo values: however, only
the increase in HR was statistically significant. Our findings are consistent
with previous findings (3) in which moderate and maximum pedal ergometry loads
were used; m an peak BAC's of 125 and 156 mg percent were attained, ergometric
inefficiency was significantly present at moderate workloads, and at maximum
workloads the VO2 was only slightly depressed but Vg and respiratory quotient
were significantly depressed. The alcohol-related inefficiency at moderate work-
loads was probably related to the circulatory adjustments to alcohol thermogenesis
(21). Therefore, BAC's of about 80 mg percent do not significantly alter the
body's overall tolerance to a moderate physical workload.

Orvhostatic Tolerance. Mean BAC during the LBNP test was adout 90 mg percent.
As shown in Tables ILI-V, 2 min of LBNP (Phase I placebo experiments at GL) pro-
duced statistically significant displacements of several physiological variables.
Alcohol was associated with greater displacements than those of the corresponding
placebo experiments at GL or at altitude. Aithough greater displacements by alco-
hol were in che direction of decreasing orthostatic tolerance, only those of SBP,
PP, and HbJz in the altitude experiments and TAFV in both GL and altitude experi-
ments were statistically significant. {n the GL and altitude placebo experiments,
half of the subjects reported mild to moderate transient lightheadedness and visual
blurring during the LBNP. Therefore, it was somewhat surprising that, in the alco-
hol experiments in which physiological decrements exceeded those of the placebo
experiments, all of the subjects reported complete absence of any adverse symptoms
during LBNP. Despite quantitative physiologica’ decrements imminent danger of
unconsciousness was not demonstrated under these experimental conditions.

Alcohol has been chown to cause diuresis beyond that induced by a comparable
amount of water intake (21). The diuresis generally occurs only while the BAC is
rising and is ascribed to an inhibitory effect of alcohol on secretion of anti-
diuretic hormone (21). As BAC falls from its peak value diuresis transitions
into oliguria but water loss continues via increased respiration and perspiration
(21). Thirst is not usually felt during acute alcohol intoxication in spite of
increasing serum osmolality but occurs only after alcohol has disappeared from
the body (21). While BAC is rising, movement of intracellular water into the cir-
culatory compartment offsets the simultaneous diuretic loss from the circulation
(21). Therefore, during the rise in BAC there is a net temporary protection against
a plasma volume decrease (21). In our study, the imbibed volume of alcohol plus
Coca Cola (about 350-550 ml) temporarily expanded the plasma volume. In general,
pestexperimental micturition was much greater in the alcohol than in the placebo
experiments. Also, both the BP and HR showed slight elevations during the rising
phase of the BAC. These elevations are consistent with the findings of others
(10,11). Because decreases in plasma volume, BP and HR are known to decrease
orthostatic tolerance (15,20), it is possible that, in our study, a net positive
effect of internal liquid exchanges on plasma volume along with the slightly
elevated BP and HR around peak BAC were temporarily protective against ortho-
static syncope during the applied LBNP.

Both HR and BP, which rise along with the BAC, have been observed to decrease as

the BAC decreases (10,11). As BAC recedes towards zero, respiration and perspira~
tion water losses continue and plasma volume decreases by loss of water to both

15


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TABLE ii.

Phase I Experiments

Experimental Protocols

Phase Ii Exper

Time Activity Time

1115 Subject Appears 1115 Subject Appears

Health Questionnaire Health Questionnaire
1130-1145 Light Lunch 1136-1145 Light Lunch
1145-1215 Seated Rest 1145-1215 Seated Rest
1220-1240 ist Arithmetic Test 1220-1240 ist Arithmetic Tesi
1250-1310 2nd Arithmetic Test 1250-3310 2nd Arithmetic Test
1315-1345 Seusor Placements 1325-1345 Sensor Placements
1345-1358 Physiological Measurements 1345-1358 Physiological Measurements
1358-1400 Ist BAC Measurement 1358-1400 1st BAC Measurement
1400-1430 Alcohol or Placebo intake 1400-1430 Alcohol or Placebo Intake
1438-1440 2nd BAC Measurement 3430-1440 Altitude Ascent
1445-1500 3rd Arithmetic Test 1443-1445 2nd BAC Measurement
1500-1508 Physiological Measurements 3445-1506 3rd Arithmetic Test
1508-1519 3rd BAC Measurement 1500-3502 3rd BAC Measurement
1515-1530 4th Arithmetic Test i 1502-1505 Physiologicai Meastrements
1530-1535 Adjust LBNP Waist Seal | 1505-1520 4th Arithmetic Test
1535-1537 4th BAC Measurement 152C-1523 Adjust LBNP Weist Seal
1537-1547 LBNP Procedure 1523-1525 4th BAC Measurement
1555-1557 5th BAC Measurement 1525-1535  LBNP Procedure
1600-1608 Pedal Ergometry 1535-1537 5th BAC Measurement
1608-1610 &th BAC Measurement 1537-i547 Altitude Descent
1610-1625 Sensor Removal 1547-1555 Pedal Ergometry

1558-1600 6th BAC Measurement
1600-1615 Sensor Removal

&



Pi = Phase I experiments at GL only

PII = Phase Il experiments at 3,648 m MSL altitude

ww

TABLE 1. Age, Height, and Weight Data
Age Height Weight Xo. of
(yr) (om) (kg
| ~ | [ f j
x 29.3 j 178.6 92.0 } ;
PI } i 6 i
SE 2.0 \ 2.2 \ 7.4 !
| t 4
~ |
| x 28.2 } 278.5 74.0 '
PIL | | 19 i
SE 0.8 | 2.9 3.1 i i
4 H H
X = mean SE = Standard error of the mean


the intracellular compartment and t- the urine (21). The net effect of these

water losses usually remains uncompensated during BAC recession since thirst
does not ordinarily return until the alcohol has disappeared from the body (21).
These observations suggest the possibility that the accommodation to applied
orthostatic stress during peak BAC may diminish during BAC recession. To our
knowledge orthostatic tolerance has not been tested during BAC recession.

16


The subject returned one week later for
for any potential effects of expe ental
hol in the first experimental session and the rene
second experim-ntal session. The data were pooled and,
t test (19), were statisticaliy compared on the basis of
conditions. tatistical sign
(19).

order,

Specifically measured variables were:
pressure (BP) using auscultative manometry; 502 using an ear oxi
temporal artery blood ficw velocity (TAFV) using a directional Doppier device
3). Besides HR and BP, pulmonary ventilation (¥,), respiratory frequency (£),
tidal volume (Vp), and oxygen uptake (¥0)) were measured guring peda! ergonetr:
Gas volumes were expressed as volume per xg of body weight. The CM; lead (2) wes
used to monitor ECG function. nis signal was fed to an oscil for visua:
ECG monitoring, 2 cardiotachometer for cont us indication ndaré
ECG recorder for periodic sampling. Also monitored were the digital meter of the
HBO. for any indication of hypoxemia and the oulsatile meter signal of the TAFV
for any flow-reversal dication approaching synccpe (13). At tude,
criteria for immediate termination of YY exp: nent consisted of strong subje.
tive symptoms of impending syncope (lightheadedness, nausea, and grayout, tun-
neling, or blackout of vision) accompanied by hypotension and bradycardia (12),
ECG evidence of ischemia or arrhythmia, TAFV approximating zero, and f
velues of HbO, below 80 percent.

usiy

eter (8); and

During each altitude exposure cne researcher remained in the hypob,
chamber with the subject. Emergency medical ecuipment, 100 percent oxygen an
a staff physician were always available on a standby tasis. Because each sub-
ject breathed through a valve mouthpiece 4 g pedal ergometry
nand signals were taught to each one to communicate th. ything i

“subjective distress is present," and "stop the test."

Temperature and relative humidity in the hypobaric chanbe:
within the ranges of 21,4°9-24,4°C and 19.0+-26.9 percent, respectivei

RESULTS.

Figure 1. presents’ the mean BAC velues measured du’
experiments, In hsth phases the mean BAC peaked slight
and did so within 30-60 min after comple
peak occur.2d earlier in the Phase = the Phase I
GL experiments, These data are consistent with these of two previous CAMI

studies (10,11) which used the same protocol for alcohol The BAC which
existed at the time of each testing procedure was obta:
from each subject's plotted curve of BAC versus time.

ng Phases
above 90

L

yet

The data testing proceduves are summar:
Starred mean vy. these tables indicate statistically sign
ferences between alcohol and placebo conditions.

on


ans

ee


In Fhase € GL experinent:
Statistically significan
and increments in HR d a4

s

iated with statistically signif lic 3P @PB, 7.
mean arterial pressure (AP, Table IV), aad HbO, (Table V); HR increased (Table V).
During LBNY at altitude eicoho! (as compered tc placebo) wes associated wi
statisticaliy significant decreases in sys c Table
sure (PP, Table IV), and TAFV (Table V); increased (Table V). erithmet
performance and eye/hand coordination at al ude, alcchel fas compared to sf!
was associated with st tic y significant decrements (Table V ri
postaltitude ergometry aicchol (as compared to placebo} was associated with
statistically significant increase in HR (Taole VI).

DISCUSSION
The statistically significant displacements associated with aicoh in
Phase II experiments were of greater magnitude than were the corresponding statis-

tically significant displacements that cccurred in Phase Placebo experiments.
Alcohol caused significant decrements in beth physiologicel and psychomotor
functions without causing the subject to lose useful consciousnes>.

Altitude Tolerance. The svpply of cerebral oxygen needed to maintain useful
consciousness dpends on both the amount of oxygen in tne arterial blood and the
tate of blood flow threugh the brain. The thermogenic effect of moderate alcohol
intake and its resultant compensating heat lass via cutaneous vasodilation

well known (21). The resulzing decrease in centrai blood ve” 12 is compensated
by vasoconstriction of centras arteries and by an increase in HR (21). When
alcohol intake is combined citude expesure (3,043 =} some of the vaso-—
constrictor compensation is Tost \DBr and AP data in Tables III and TV) but cer~
ebral circulatory adequacy is mainteined by increased ER (Table ¥).

The mean decrease in HbO2 from GL to 2 3,348 = eititude was significantly
greater in the alcohcl than in the corresponding placebos experiments (Tabie V}
This finding is consistent with that of a previous study (9). The lowest mean
HbCy vaine (Table V) at altitude in the sicohol condition was 86.3 percent.
Although lower than the correspon ing Placebe value at altitude, the mean value
of Hedy approaches ti. lower edge of the adequately compensated EbQg range
(> 85 percent) for a 3,048 =m altitude (16). Because a decreased but minimally
adequate mean HbO2 existed et altitude in our study, the stetis aiiv signi
cant decrements in borh arithmetic and eye/hand ccordination performances
{Table VII) associated with the alcohcl condition were probably related to a
histotoxic yether than hypoxic effect of alcohol (16). This correborates the
sta cally t decrements in arithmetic performance h occurred
in Phase I GL experinents h cerebral bicod ficw (TAFV data) and HbO2
{normoxia} were both fuliy adequate. These findings are consistent ‘i these
of another study (4) conducted “ender az altitude and peak BAC conditions.
Adjunct Gate analysis revealed that viéual decrezents in hemeter perforn-
ance were greater when the BAC was rising than when it wes subsequently falling.

This general pattern is also consister ).
Therefore, although alcohol quantitatively re
involved in aititude tolerance, @ substantial conprosise ef vance

was not demonstrated,



Figure 1. Blood Aicchol Concentrat
BAC = Blood alcohol concentraticn in mg percent
GL = Ground level altitude of 388 m
Alt. = Hypobaric chamber altitude of 3,048 m MSL
® = Mean BAC values Phase I GL experiments
© = Mean BAC values for Phase
Ry Ro» Rg = Periods of res
measurements
ERGO = Perioé of pedal ergometry at 50
MI, MEI = Two arithmetic end eye. c
LBNP = Lower body negative pressure of -49 torr
éifferential pressere for 2 nin

«
coordination tests



boundary lines. Each block measured 9 m dy 20 m.
equaled the number of boundary violations per min of teta
test evolveé from Phase I observations that the intoxicated subjects experienced
substantial difficulty with writing during the arithmetic tests.
subsequently added to the Phase II experiments. Simple arithmetic has pre
been shown to be adversely affected by peak BAC's as low as 35 mg percent (7).
Our experience has shown that the asymptotic portion of the iearning curve for
t combined psychomotor test is attained by the fourth test. Any resicual
learning differences were accounted for in the randomization of experimental
order. The effects of alcohol versus placebo on the arithmetic and eye/hand
coordination scores were based only on the two tests taken efter intake of the
alcohol or the placebo.

After completing the second arithmetic test, the subject donned a surgical
scrub suit and was taken to the hypobaric chamber where he wes instrumented for
subsequent testing. He was then seated in our LBNP bex and loosely seaied in
it from the waist down. The LBNP box and l ergometer have been
described elsewhere (14). After 10 min of resting physiclogical neasure:
the subject provided the first pair of BAC measurements in order
starting BAC of zero.

Alcohol intake started at 1400. The
100 proof bonded bourbon per kg of body weig’ standard" ma:
weight, 170.2 cm in neight and 1.81 m* of body surface area (BSA). The total
load for such 2 man would be 140 mi (asout 4.66 oz} of 100 provf bourbon. The
lead for each subject was proportional to his BSA as caiculated from his measured
height and weight (6). One part bourbon per two parts of Coca Cole mixed,
divided equaily into three drinks and drunk at an even rate over 4 cé of 36
min. In the placebo experiments, an ecuel veiume of tap water replaced the bour-
bon in the mixed drinks. Ail drinks were served

Ascent to chamber ait
tion of alcohol or placebo
the subject provided the seco:

test, the third pair cf BAC mea:
of the LBX

waist seal an
s time, the subject had
nee the end of alcoh

of BAC measurenents e
Att tude for 45 rin; 55

s

This consisted of 8 min
physiological measurements after which the subject underwent an LBNP
for 2 min. A fifth pair of BAC meastrements ensued. The chamber was 2
returned to GL in 10 min, The subject next underwent pedal ergometry of 30 %
for 2 min and 50 W for 6 min. After the subject rested for 5
pair of BAC measurements was obtained, all sensors were removed, and the subject

changed to his street clothes. In the aicohol experiment, the subject's BAC was

monitored until it approximated 40 ng percent, at which tine a researcher per-

sonally transncrted the subject to form i
ject's agreement to abs from operating eny vehicle or hazardous mact
until the next day.

i



ALCOHOL-INDUCED PHYSIOLOGICAL DISPLACEMENTS
AND THEIR EFFECTS ON FLIGHT-RELATED FUNCTIONS

INTRODUCTION

Billings et al. (1) amply demonstrated that alcohol degrades a pilot's
ability to safely operate an aircraft. They studied the effects of various
blood alcohol concentrations (BAC's) on the capability of instrument-rated
pilots to execute instrument landing approaches in light aircraft. They found
that significant increases in the number and potential seriousness of proce-
dural errors occurred at BAC’s as low as 40 mg percent and that these errors
increased as the BAC was increased up to 120 mg percent. BAC's lower than
40 mg percent were not evaluated (1). Previous Civil Aeromedical Institute
(CAML) studies have assessed some of the effects of alcohol on altitude tol-
erance (10,11) and on psychomotor performance (4).

Ryan et al. (17) recently reported that the incidence of fatal accidents
associated with alcohol decreased gradually from 43 percent in 1963 to approx-
imately 16 percent for the 1969-1976 period. Unpublished data from the Avia-
tion Toxicology Laboratory of CAMI revealed that an average of 8.5 percent of
fatal aviation accidents were associated with alcohol for the 1968-1979 pericd.
The difference between this 8.5 percent incidence value and the 16 percent
incidence value reported by Ryan et al. is due mainly to the fact that the
minimum BAC associated with a fatal accident was defined as 40 mg percent in
the CAMI study and 15 mg percent in the study by Ryan et al. CAMI toxicolog-
ical data further show that the fatal accident rate associated with BAC's in
excess of 40 mg percent in 1980 was 6.5 percent; in Fiscal Year 1981 (October 1,
1980, to September 30, 1981) an ali-time low incidence of 5.1 percent was veached.

Despite 2 Federal Aviation Regulation {Part 91.11) (8) which prohibits the
operation of civil aircraft while the pilot is under the influence of alcohol,
or within 8 h after the consumpticn of any alcohol beverage, a recent survey (5)
reported that abeut 30 percent of general aviation (GA) pilots considered flying
after moderate social dzinking to be safe behavior.

Many of the physiological effects of alcohol are well known. The thermogenic
effect of moderate alcohol incake produces increased heat loss by means of periph-
eral cutaneous vasodilation (21). The resulting decrease in central blood volume
is compensated by vasoconstriction of central arteries and dy an increased heart
rate (HR) (21). The diuretic effect of alcohol occurs only while the BAC is ris-
ing and is ascribed to ax inhibitory effect of alcohol on secretion of antidiu-
retic hormone (21). Increased respiration and perspiration resulting from thermo-
genesis also increase loss of body water (21).

The purpose of this study was to determine the presence and degree of alcohol-
related physiological decrements that could compromise safety of flight. Specifi-
cally, our study was directed at assessing the effect of alconol on an individual's
ability to: (i) tolerate altitude as measured by maintenance of adequate oxyheno-
globin saturaticn (Hb02) and psychomotor performance; (ii) maintain adequate



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TABLE VIL. Arithmetic and Eye/Hand Coordination Testing

Arithmetic Score i Arithmetic Score Ii
Alc./Plac. Alc./Plac.
Alc. Plac. x100 Alc. Plac. X100
_ | i | i
x 1.30 0.57) | 215.0 1.32 O.51 { 254.3 |
PI i | * | *|
SE i 0.47 H 0.18 | 35.2 0.41 0.10 56.5
| | i i
x | 1.20 | 0.62 ; 233.2 0.95 0.66 | 201.5
| PIT : a}: i
; SE 0.53 0.24 | 45.9 0.48 0.32 71.4
Coordination Score I Coordination Score it
Aic./Plac. Alc./Plac.
Alc. Plac. x100 Alc. Plac. x100
x 0.98 0.22 730.5 1.25 0.18 858.8
PII * ®
SE 0.24 0.06 184.7 0.34 0.05 131.2
‘X = mean SE = Standard error of the mean

Alc. = Alcohol condition

Plac. = Placebo condition

I = Phase I experiments at GL only

PII = Phase II experiments at 3,048 m altitude

Arithmetic Score = Number of incorrect answers per minute of time for
test completion
Coordination Socre = Number of block-boundary violations per minute
of time for test completion

Mean BAC in PI during arithmetic test I = 83.3 mg percent
Mean BAC in PI during arithmetic test II = 90.9 mg percent
Mean BAC in PII during arithmetic test I and Coordination Scere I = 85. mg percent
Mean BAC in PII during arithmetic test II and Coordination Test II = 90.6 mg percent

* = Statistical significance at p < 0.05


ACKNOWLEDGMENTS

The authors thank Brs. Aucie W. Davis, Jr., Marinus Flux, and
Gordon A. Bocox for screening physical examinations of subjects;
Dr. Kurt M. Dubowski, University of Oklahoma Medical Center, for
his expert advice on breath-alcoho? analysis erd apparatus calibra-
tion; and Charles Valdez, Jimmy Lee Whitley, Harold Dale Nelson,
David Hehmeyer, and Joe Nix for hypobarie chamber operations.

Accession For

NIIS GRA&I A
DTIC TAB

‘Availobi
“avail ané/or

Dist H Special

i

ai


Techniccl Report Documentation Page

TEEIR EFFECTS ON FLIGHT-RELATED FUNCTIONS |

[Tr Report No. 7. Government Accession No. TS. Recipient's Covaleg No }
PAA-AM-82-3
i]
AD-AN5973,
4, Title ond Subtitle 5. Report Date :
:
1
ALCOHOL-INDUCED PHYSIOLOGICAL DISPLACEMENTS AND re arch. 282 — Sole :
i
|

ics Performing Orgenseton Report No.

7 Author's)
Michael T. Lategola, Peg J. Lyne, and Mary J. Burr

9. Performing Orgenization Neme ond Address. VO. Work Unt No (TRAISE
FAA Civil Aeromedical Institute
P.O. Box 25082 TT. Contract or Gront No

Oklahoma City, Oklahoma 73125 i

13. Type of Revert and Period Covered

Sponsoring Agency Nome ond Address

Office of Aviation Medicine OAM Report
| Federal Aviation Administration
I $00 Independence Avenue, SW 14. Sponsoring Agency Code

Washington, D.C. 20591

15. Supplementary Notes

This report was prepared under task AM-A~8i~PHY-122.

16. Abstract
Tolerances of human subjects for orthostasis and physical work were determined
at a simlated altitude of 3,048 m. Orthostesis was induced with a lower body
' negative pressure (LBNP) device and physicci work was done on a pedal ergometer.
Altitude was simulated in a hypobaric chamber. Tests were carried out under two
| experimental conditions: (i) after subjects drank an alcoho
H after subjects drank a placebo beverage (uo alcohoi). The alcoholic beverage
produced blood alcohol concentrations (BAC’s) of about 90 mg/100 mi of blood
{90 mg percent). At altitude, arterial oxyhemoglobin saturation (Hb02) remained
adequately compensated but was lower after alcohol than after placebo intake.
Arithmetic and eye/hand coordination performances were both significantly
decreased after alcohol. Ergometry, after alcohol, was well tolerated despite
some decreased cardicrespiratory efficiency. The LBNP applied around peak BAC
at altitude was tolerated without subjectively adverse symptoms despite signif-
icant decreases in several cardiovascular parameters. Cardiovascular adequacy
along with maintained plasma volume around peak BAC appeared to be temporarily
protective against orthostatic incepacitation during LBNP. Reversal of this
temporary orthostatic protection during BAC recession is possible.

beverage, or (ii)

Orthostatic tolerance, Physiological |Service, Springfield, Virginie 22
functions, Arithmetic accuracy,
Eye/hend coordination

7, Key Words 16. Distribution Statement
Alechol, Private pilots, Altitude Document is evailable to the public
tolerance, Physical work tolerance, {through the National Technical Information

19. Security Classif. fof this report) TT ® Security Clessif. (of this rage? ] 2 Ne. of Pages | 22, Price
i {
Unclassified | Unclessified 18 i
i i i

i
Form DOT F 1700.7 (8-72! Reproduction of completed page cuthorized


TABLE IIl.

Syst

Blood Pressure

(SBP) and Diast

c Blood Pressure (DBP)

SBP (mmHg) SPY (% of Control)
Ry RQ R3 LBNP R3/R, X100 LBNP/R3 Xi00
| X ]) 123.4 | 223.0 | 121.9 | 115.7 98.6 94.8
} PL Alcohol
{ SE 2.9 4.1 4.7 5.3 2.1 1.5
t
x 121.3 125.3 | 120.8 115.0 99.8 95.3
Pi Placebo
SE 4.1 4.1 2.8 2.4 1.7 1.2
x 1211.4 | 112.4 | 122.8 | 99.8 102.2 88.1
PIL Alcohol
SE 3.3 4.2 4&4 6.0 1.4 3.0
x 113-8 | 115.7 | 116.9 } 112.9 104.6 96.2
PII Placebo
SE 3.3 3.7 3.8 5.2 1.7 1.6
DBP_Gnmtig) DBP _(% of Control)
Ri R2 R3. -LBNP R3/R1 XL00 LBXP/R3 X100
‘
x 61.8 $3.9 61.9 65.2 101.1 105.8
FI Alcohol
SE 4.2 3.5 3.5 2.8 5.0 2.4
x 61.5‘[ 61.3 64.3 66.0 104.8 102.0
PI Placebo
SE 3.8 6.2 4.0 5.7 3.6 4.3
xX 62.0 | 63.8 | 60.6 | 59.4 97.€ 99.6
PII Alcobol
SE 2.2 3.4 2.9 2.5 3.8 3.2
x 59.3 | 63.9 | 65.8 | 63.6 111.0 97-0
PII Placebo
SE 2.2 3.2 2.6 2.4 2.4 2.1
1
L-
X = mean SE = Standard error of the mean PI = Phase I experiments at GL only
Ry. Ro, Rg = Periods of resting physiological PIE = Phase II experiments at 3,048

measurements
LBNP = Lower body negative pressure of -40 torr for 2 min
* = Statistical significance at p < 9.05

10

MSL altitude

n


|
PI Alcohol =|
| i
- { 3
x 147.4 61.4 83.8 | 9.0 | 95.9 |
PI Placebo : i { |
SE 6.9 46 | 8.9 ee ee
\ i
. i + i 4
_ : ! H
x 146.4 64.4 | 82.0 | 91.7 3} 105.6
PII Alcohol : | *
SE 7.8 3.4 0 6.1 : 4.4 | 24!
i | t |
x 139.4 64.7 74.7 1 89.6 $7.3
PII Placebo :
SE 6.2 3.0 45} 3.8 3 2.5
: t t
Yo /kg TAFV £ Vil ke
(2l/nin/kg)  (om/s) (xp) (ml/kg)
i i {
x 10.2 | 3.8 266.0 23.8 | 42.2
Pl Alcohol i
SE 0.7 0.7 33.9 | 1.9 Lit
i
i
x 10.0 | 4.5 250.2 22.6 | 12.0
Pl Placebo {
SE 0.8 0.9 25.6 | 14 | 1S
}
L !
f = | 1 45 i
x 12.0 3.7 296.3 | 20.4 | 15.4 |
PII Alcohol : H
SE 0.3 3 0.5 1.8 18 |
i Hl ' H
j x iL 4.3 20.8 | 38k} 16.8
PII Placebo i t
{ 4.3 0.7 13.1 heb i.4 |
| i i \
|
‘X = mean SE = mean SBP = Systoii

DBP = Diastolic blood Pulse pressure AP

TAFV = T
weight
Letion per kg of body
respirations per
2 pressure of -40 tor
cance at p < 2 05 ¥

Phase I exper:
PIL = Phase
3,048

volume

13