530 Western Society for Clinical Research

present in the skeletal muscles (soreness, weak- ness or paralysis of muscles), the cardiovascular system (cardiac dilatation, tachycardias, gallop rhythms) and the gastrointestinal tract (ileus).

Correlation of urine chloride excretion with serum chloride level, as a gauge for the preven- tion of alkalosis, was made in several patients. These studies showed that the urine chloride test was not always a reliable means of detecting plasma chloride deficits.

These studies indicate the need for prophy- lactic use of repair fluids containing all electro- lytes which may be lost from the body during periods of prolonged intravenous therapy. CORRELATION OF THE ANALGESIC RESPONSE

TO NITROUS OXIDE AND NITROUS OXIDE-

AMPHETAMINE WITH PERSONALITY FACTORS. Janice Norton, B.A. (by invitation), Mark Nickerson, Ph.D. and Agnes M. Plenk, M.A. (by invitation). Salt Lake City, Utah. (From the Departments of Pharmacology and Psychiatry, University of Utah College

of Medicine.) Wide individual variations in the response of

patients to analgesic agents are frequently en- countered but the basis for this is poorly under- stood. The role of depression of higher levels of the central nervous system in the production of NzO analgesia, and the frequent appearance of behavior characteristic of release from cortical inhibition in patients receiving this agent sug- gested that personality factors might be of particular importance in modifying its effect.

In an effort to evaluate the significance of personality in altering the response to analgesic concentrations of NzO, nine medical students were subjected to Rorschach testing and were ranked on the basis of six factors: (1) conformity, (2) anxiety, (3) ego strength, (4) introversion, (5) emotional control and (6) hostility. Pain thresholds were determined on the same indi- viduals by two methods: (1) the time required for deep pain to develop in a hand placed in water at 4’~. after equilibration at 30”~. and (2) the Hardy-Wolff-Goode11 radiant heat technic for cutaneous pain. After studies of control thresholds, responses to N20 (33 per cent in O2 by face mask) with or without dextro-amphet- amine (10 mg. orally) were determined.

High absolute pain threshold was found to be positively correlated with introversion, hostility and relatively low emotional control. In addi- tion, individuals with a high emotional tension

(the most anxious, hostile and conforming) responded to NzO with the greatest rise in threshold. Their analgesic response was also less completely antagonized by amphetamine than was that ot other members of the group.

These observations indicate that NzO anal- gesia is associated with a generalized release of emotional tension. Individuals with high com- ponents of psychic factors indicative of tension receive the greatest analgesic effect from the agent, tend to maintain this analgesia in spite of amphetamine antagonism and appear to be the most likely to exhibit bizarre behavior while under its influence. PERSONALITY PROFILES IN PATIENTS WITH

ESSENTIAL HYPERTENSION. Robert E. Harris, Ph.D. (by invitation) and Maurice Sokolow, M.D. San Francisco, Cal$ (From the

Divisions of Psychiatry and Medicine,

University of California Medical School.) Clinical psychiatric studies of patients with

essential hypertension have provided a number of hypotheses concerning the possible contribu- tion of psychogenic factors to the disease process. Critical tests of the validity of these hypotheses are difficult to design because of the inherent subjectivity and lack of control in the clinical interview. Objective personality measures de- rived from the Minnesota Multiphasic Per- sonality Inventory allow for the elimination of subjective factors, the influence of preconceived hypotheses, etc., and for a critical test of some of the hypotheses suggested by the clinical psychiatric data.

Personality inventories were obtained on eighty patients with essential hypertension. These profiles were contrasted with those ob- tained from normals, patients with duodenal ulcers and patients convalescing from a variety of physical diseases, operations, accidents, etc. Group averages, group profiles and individual profiles were analyzed for deviation from nor-

mality and for characteristic kinds of defenses against anxiety.

More than three-fourths of the hypertensive records were abnormal and significant differ- ences from the other patient groups were obtained. In general the hypotheses derived from clinical psychiatric interviews were con- firmed. Personality characteristics include overly rigid defenses and difficulties in the control of hostile impulses. A full description of the patients

AMERICAN JOURNAL OF MEDICINE