Experience and endocrine stress responses in neonatal and pediatric critical care nurses and physicians.

OBJECTIVE: Critical care is a working environment with frequent exposure to stressful events. High levels of psychological stress have been associated with increased prevalence of burnout. Psychological distress acts as a potent trigger of cortisol secretions. We attempted to objectify endocrine stress reactivity. DESIGN: Observational cohort study during two 12-day periods in successive years. SETTING: A tertiary multidisciplinary neonatal and pediatric intensive care unit (33 beds). SUBJECTS: One hundred and twelve nurses and 27 physicians (94% accrual rate). INTERVENTIONS AND MEASUREMENTS: Cortisol determined from salivary samples collected every 2 hrs and after stressful events. Participants recorded the subjective perception of stress with every sample. Endocrine reactions were defined as transient surges in cortisol of >50% and 2.5 nmol/L over the baseline. MAIN RESULTS: During 7,145 working hours, we observed 474 (12.5%) endocrine reactions from 3,781 samples. The mean cortisol increase amounted to 10.6 nmol/L (219%). The mean occurrence rate of endocrine reactions per subject and sample was 0.159 (range, 0-0.43). Although the mean raw cortisol levels were lower in experienced team members (>3 yrs of intensive care vs. <3 yrs, 4.1 vs. 4.95 nmol/L, p < .001), professional experience failed to attenuate the frequency and magnitude of endocrine reactions, except for the subgroup of nurses and physicians with >8 yrs of intensive care experience. A high proportion (71.3%) of endocrine reactions occurred without conscious perception of stress. Unawareness of stress was higher in intensive care nurses (75.1%) than in intermediate care nurses (51.8%, p < .01). CONCLUSIONS: Stress-related cortisol surges occur frequently in neonatal and pediatric critical care staff. Cortisol increases are independent of subjective stress perception. Professional experience does not abate the endocrine stress reactivity.

Objectifying psychomental stress in the workplace--an example.

BACKGROUND: Psychomental stress is a major source of illness and reduced productivity. Data objectifying physiological stress responses are scarce. We studied salivary cortisol levels in a highly stressful environment, the pediatric critical care unit. The aim was to identify targets for organizational changes, to implement these changes and to assess their impact on cortisol levels. DESIGN: Repeated measurements observational cohort study (before and after intervention). SUBJECTS: 84 nurses working in two independent teams (A and B) in a 19 bed pediatric intensive care unit. Between study periods team A experienced a major exchange of experienced staff while the turnover rate in team B remained average. MEASUREMENTS AND INTERVENTIONS: Salivary cortisol samples were collected every 2 h and after stressful events. Nurses in study period I showed elevated cortisol levels at the beginning of the late shift, interpreted as an anticipatory stress reaction. To ease conditions during the early part of the late shift (conflicting tasks, noise and crowding), we postponed the afternoon ward round, limited non-urgent procedures and introduced a change in visiting hours. The early shift, which was not affected by the intervention, served as control. MAIN RESULTS: Both crude and adjusted analysis revealed a decrease of cortisol levels at the beginning of the late shift in team B (p = 0.0009), but not in team A (p = 0.464). The control situation showed no difference between teams and study periods. INTERPRETATION: We demonstrated reduced cortisol secretions in one team following organizational changes, which was probably overridden by the disruption of social coherence in the second team.

[Depressive affect and surrogate markers in HIV infected patients]. / Depressivität und Surrogat-Marker bei HIV-infizierten Personen.

The present study investigates whether there is a relationship between subjective well-being and the change of immune markers in HIV-infected subjects. Twenty-one HIV-infected persons completed questionnaires. Immune markers (CD4-percentage and CD4/CD8-ratio) were measured at the beginning of the study, after 8 months and after 15 months. In a hierarchical multiple regression model, baseline values of immune markers explained most of the variance of the immune markers, both after 8 and 15 months. After including several control variables in the model, depression values and the values on the symptom checklist explained an additional increment of variance of both immune markers after eight months. Therefore, data of the present study suggest that predominantly depressive feelings co-determine immune status in HIV-infected persons.

Effects of work demands on immunoglobulin A and cortisol in air traffic controllers.

The professional activity of air traffic controllers (ATC) is often considered to be rather stressful. Certain characteristics of this job are likely to produce stress; for example an ATC can not predict when a situation becomes critical and he is not able to regulate the workload. In order to assess psychophysiological stress reactions in this working situation, saliva samples were taken from 158 male air traffic controllers before and after each of two working sessions. In contrast to the expected immunosuppressive effects, the working sessions caused a marked increase in the concentration and secretion rate of salivary immunoglobulin A (sIgA), as well as in the concentration of salivary cortisol. The increase in sIgA, however, was not correlated with the salivary cortisol response or with the amount of actual or perceived workload, whereas the cortisol response was correlated with both workload measures. It is suggested that positive emotional engagement is responsible for the observed sIgA increase and that measuring this physiological response may be a valuable tool for differentiating between positive and negative stress effects or between successful and unsuccessful adaptation or coping with situational demands.

Electrocortical and autonomic alteration by administration of a pleasant and an unpleasant odor.

The present study was designed to investigate whether there is a consistent response in ongoing EEG due to repetitive olfactory stimulation. Two odors of different hedonic quality were presented bilaterally to five male subjects at suprathreshold levels. A room-air blank served as the control stimulus. Each odor was presented six times to each subject in each of three sessions. Electrocortical activity, heart rate, skin conductance and breathing cycle were recorded continuously. EEG variables assessed were difference scores of absolute power in the frequency bands theta, alpha 1, alpha 2 and beta 1 at eight locations. Phenylethyl alcohol was rated pleasant, while valeric acid was judged unpleasant. Within 8 s after stimulus release, valeric acid increased alpha 2 power, whereas phenylethyl alcohol did not. No further frequency bands were affected by olfactory stimulation. These findings suggest that smelling an unpleasant odor leads to a cortical deactivation.

Electrocortical, autonomic, and subjective responses to rhythmic audio-visual stimulation.

The present study was designed to test the hypothesis that varying sensory input can affect mood, autonomic arousal, and electrocortical activity. Twenty right-handed males were exposed to three rhythmic audio-visual stimulation programs, with either a high intensity and variety of stimuli (program H), a low stimulation (program L) or with a transient from high to low (program HL). Multichannel EEG, heart rate, and skin conductance were recorded continuously, and after each trial mood was rated on a bipolar adjective list. EEG data were subjected to FFT dipole approximation procedure, and dipole locations and field strength (Global Field Power) were analyzed for the frequency bands theta, alpha, and beta 1. Mood ratings clearly differed between programs H and HL, with highest values of arousal after H. Programs L and HL decreased autonomic arousal, whereas H induced deactivating as well as activating effects. Field strength of the alpha band decreased similarly during all programs. Dipole sources were located more to the left in the alpha band and more to the right in the beta 1 band during all programs as compared with baseline. Therefore, programs affected mood and autonomic variables differently, but not electrocortical variables. The higher activation of the right hemisphere during all programs is interpreted as an indication that audio-visual stimulation does induce changes in the brain, such as are commonly found in altered states of consciousness.

Workload and psychophysiological stress reactions in air traffic controllers.

Interactions between workload and psychophysiological stress symptoms were investigated in a population of 205 predominantly male air traffic controllers (ATCs) from the area control centre (ACC) and the airport control tower (TWR) in Zurich and Geneva. Each subject completed two questioning sessions and two working sessions, the first time during a period of low traffic and the second time during a period of high traffic. For the questioning sessions standardized questionnaires were used. For all investigated working sessions, different aspects of the subjective and objective workload were recorded. Before and after each session, a saliva sample for assessing the concentration of secreted cortisol was taken. The questionnaire parameters represented psychological stress symptoms, such as complaints of physical discomfort, depression, negative self-communication, work-increased anxiety, coping behaviour and subjective rating, and interpretation of various aspects of the working situation. The mean values measured were within the normal range, and only a few significant differences between the two questioning sessions were found. However, about 10 to 15% of the ATCs showed elevated values in psychological stress symptoms to an extent indicating that they might have serious stress problems at work and/or in their private life. The investigated working sessions showed that the ATCs' subjective ratings correspond clearly to their cortisol response and the objective workload. Thus, ATCs' complaints regarding excess work stress should be taken seriously.

[Assessment of musculoskeletal disorders using a questionnaire]. / Erfassung muskuloskeletaler Beschwerden mittels Fragebogen.

The standardized illustrated questionnaire on musculoskeletal disorders of the Japanese Committee on Occupational Cervico-branchial Disorders was translated into German. This questionnaire, composed of 37 items about the occurrence (never/seldom, occasionally, almost daily) of symptoms (pain, stiffness, fatigue) in twelve body regions, was used together with medical examinations (pressure points), and further information was gathered on the consumption of analgetics and medical visits prompted by musculoskeletal symptoms. The questionnaire's reliability and validity were tested in 644 persons from twelve occupational groups within the service sector. Factor analysis showed that symptoms can be grouped into four distinct regions of occurrence: neck/shoulder/area, back/low back, and both left and right upper extremities. Indices based on these regions are consistent (Cronbach alpha approximately 0.8). Palpation findings steadily increase with increasing index values. The consumption of medicaments and medical visits positively correlate with the indices. Consequently the questionnaire is judged to be a valid instrument for studying musculoskeletal disorders at the workplace.

Complementary functions of the two brain hemispheres: comparisons with earlier conceptions and implications for individual and society.

The concept of different functions for the left and right cerebral hemispheres coincides in an astonishing way with earlier philosophical and psychological work which divided the human mind into two complementary functions without having a neurophysiological explanation. Representative are the ideas of Fichte, Hegel and Jung. The latter postulated the two subsystems Ego and Self and associated the conscious functions of the Ego with the intellect, the capacity for rational thought, and the Self with the mind, which also includes the emotional feelings. For the harmonic development and self-realization of man the functions of both systems in complementary interaction are required. Therefore, the current overaccentuation of the intellect and of progress directed technical-scientific thinking should be corrected by making better use of the much neglected functions of the right hemisphere.

[Aerobic capacity estimated from heart rate under submaximal load: an indicator of complaints, personality, personal activity and social status]. / Geschätztes Sauerstoffaufnahmevermögen aus der Herzfrequenz bei submaximaler Belastung: ein Indikator für Beschwerden, Persönlichkeit, Eigenaktivität und Sozialstatus.

In 34 young females (mean: 21 years, range 18-30), working with VDTs, maximum aerobic capacity (MAC) was estimated by use of a cycle ergometer and Astrand's nomogram. MAC correlated with musculoskeletal complaints (-.29, p less than .05), eye complaints (-.36, p less than .05), personal activity (.38, p less than .05), personality dimensions: "Imperturbability" (.41, p less than .01), "Wellbeing" (.31, p less than .05), "Traditionalism" (-.45, p less than .01) and "Psychophysic constitution" (all evaluated by questionnaires), a body weight index (-.51, p less than .01) and systolic blood pressure after performance (-.51, p less than .01). MAC also distinguished significantly between a priori classified subgroups with seldom or frequent musculoskeletal complaints, the latter scoring higher (31 vs. 25 ml O2/kg X min), and subgroups with high or low EMG values of the trapezius muscle, measured at the workplace (25 vs. 33 ml O2/kg X min). A similarly ascertained MAC separated a comparable group of 55 young female university students (mean: 21 years, range 19 to 27) from the VDT users (38 vs. 27 ml O2/kg X min). It is concluded that the indirect estimation of MAC using Astrands nomogram is sensitive enough for certain practical uses and that MAC shows significantly plausible relations to a set of personality factors, social status, complaints and physiological variables to serve as a reliable indicator for personal fitness.

Arousal reduction with biofeedback-supported respiratory meditation.

This study investigated the effectiveness of a relaxation procedure that combines a concentration aid, in the form of biofeedback, with elements of approved relaxation procedures. Ten subjects completed two sessions, one with and one without feedback. Half of the subjects started with the feedback session and then completed the session without feedback; the other half had the reverse order. In the experimental procedure, subjects had to concentrate on their exhalation, being supported by respiratory feedback. In the background they heard slow movements of baroque music and relaxation-suggesting sentences. The control procedure contained only background music and relaxation-suggesting sentences. Both procedures elicited a trophotropic response: Finger temperature increased while skin conductance level, number of skin conductance responses, and muscle tension decreased. However, with respiratory feedback and meditation, there was an additional, specific effect, a decrease in respiration and heart rate, to an extent not found in the control procedure. It is suggested that exhalation feedback helps to concentrate on the exhalation process and by this means slows respiration rate, and as a consequence, also heart rate. Therefore, respiratory feedback could be a useful tool for inducing relaxation and slowing of heart rate.

A field study on vegetative effects of aircraft noise.

Sound level, electrocardiogram, electromyogram, skin conductance, and respiration were recorded under field conditions in 33 airport area residents. During the rcordings, the subjects had to perform different activities (e.g., filling out forms, concentration test, noise assessment, relaxation, and direct conversation with the experimenter). The different activities caused significant shifts in clusters of physiological data in all subjects. Aircraft noise and incidental background noise caused such shifts in the majority of subjects. Subsequent correlational and cluster analysis for the effects of sound intensity revealed interactions with the type of ongoing activity. Vegetative noise responsiveness was not correlated with noise exposure level and subjective complaint behavior, but was correlated with vegetative responsiveness to the different ongoing activities.