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PubMedDate not supplied

Are automated anesthesia records better?

STUDY OBJECTIVE: To determine whether data recorded by an information management system is significantly different from that recorded manually. DESIGN: A comparison was made between 13 handwritten and 13 computer-generated anesthesia records by calculating the frequency with which recorded variables were outside predetermined acceptable ranges. Five physiologic variables [systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), end-tidal partial pressure of carbon dioxide (PETCO2), and oxygen saturation by pulse oximeter (SpO2)] were compared during the initial 1 1/2 hours of operation. SETTING: Surgical suite at a university-affiliated hospital. PATIENTS: Thirteen adult patients scheduled for operations that required general anesthesia for longer than 1 1/2 hours. INTERVENTION: In addition to the traditional handwritten anesthesia records, an information management system (ARKIVE Patient Management System, DIATEK, San Diego, CA) was used to collect data from each case. MEASUREMENTS AND MAIN RESULTS: No significant differences were found between the methods in the frequency of elevated SBP, elevated DBP, and tachycardia. However, the manual records showed low SBP, DBP, and HR with a significantly lower frequency (2%, 11%, 1%, respectively) than the automated records (6%, 26%, 5%, respectively; p < 0.01). The automated PETCO2 readings were higher than the upper limit (40 mmHg) with a higher frequency (18%) than the manual records (3%; p < 0.01). On the automated records, SpO2 was noted to be 90% or less on two occasions, but significant desaturation was noted only once on the manual charts. CONCLUSIONS: Observer bias, missed readings, and errors of memory, which affect manual anesthetic records, may cause significant inaccuracy and may be avoided by using automated records generated by information management systems.

Anesthesia, General↗

PubMedDate not supplied

Prediction of outcome in the treatment of specific phobia. A cross validation study.

The purpose of this study was to investigate possible predictors of treatment outcome in specific phobia at 1 week after treatment, and at I year follow-up. The subjects (n = 138) came from four studies (two on spider phobia, one on blood phobia and one on injection phobia), and all had been diagnosed with simple phobia according to DSM-III-R. The dependent variable was clinically significant improvement in three different factors; avoidance behavior in a behavior test, self-rated anxiety during the test, assessor rating of phobic severity or fainting behavior. Fourteen variables covering self-report, demographic and physiological variables, and data from the behavior test were used as prognostic variables. Multiple regression analyses were used in a cross validation procedure. The results showed that diastolic blood pressure at pretest was a predictor at post-treatment for one sample and credibility was found as a predictor for the other sample both at post-treatment and at 1 year follow-up. Analyses were made for the diagnoses and the treatments but the results were inconclusive. Despite the large sample size and the cross validation procedure no stable predictors were found for short- and long-term outcome. The few significant predictors should be considered as chance findings.

Adolescent↗

PubMed2006

Individual variability, end-point effects and possible biases in electrophysiological research.

Neocortical dynamics and signals reflect spatiotemporal cortical synchronization as well as functional condition and modulation by subcortical projecting structures that determine the brain state. However, neurotransmitters interact and neuronal function and signals also reflect non-neuronal factors that should (but not necessarily are, or can) be taken into proper consideration in neuroscience. Examples in this regard are the CNS modulation by spontaneous or induced changes in metabolism (e.g. glucose, ammonia), blood flow, pO(2), pCO(2), hormones (thyroxine; sexual hormones, ATCH) and neurohormonal interaction, maturation, aging, temperature, light-dark regulation of serotonine, histamine and dopamine/melatonin/vitamin B12 secretion and interaction, etc. Hormones also regulate the (functional) maturation and differentiation between sexes both during development and in adult life. These factors interact with each other and individually or collectively can account for unexplained or underestimated individual variability; on occasions, may become critical variables in animal or human research. In specific instances, variability is the information of interest. However, physiological variability due to neuronal or non-neuronal factors can interact with the experimental setups or affect electrophysiological signals to extents that can result in biased findings in otherwise controlled studies. An "inverse problem" difficult to approach may ensue in both animal and human research; in several instances, the specificity of brain signals for the investigated function may require experimental validation.

Analgesia↗

PubMed1998

Cortical and cognitive development in 4th, 8th and 12th grade students. The contribution of speed of processing and executive functioning to cognitive development.

This study investigated cortical/cognitive relations in 30 4th, 8th and 12th grade students. All students were administered the Figural Intersection Test, a measure of cognitive development, and performed, three times with different targets, an event-related potential (ERP) oddball/selective-attention task. Two independent factors emerged from the ERP task that predicted development--speed of processing (P300 latency to Block 1 targets) and maturation of executive functioning (a composite ERP variable calculated as the ratio of RT and P300 latency divided by the accuracy to Block 2 targets). These two variables loaded on orthogonal factors in a principal components analysis, and were the only variables included in a stepwise regression of physiological variables on cognitive development. Speed of processing is modulated by myelination and synaptogenesis, and executive functioning is modulated by maturation of the frontal system. These electrophysiological markers could index these cortical transformations underlying cognitive development.

Adolescent↗

PubMed2006

Biologically variable ventilation improves oxygenation and respiratory mechanics during one-lung ventilation.

BACKGROUND: Hypoxemia is common during one-lung ventilation (OLV). Atelectasis contributes to the problem. Biologically variable ventilation (BVV), using microprocessors to reinstitute physiologic variability to respiratory rate and tidal volume, has been shown to be advantageous over conventional monotonous control mode ventilation (CMV) in improving oxygenation during the period of lung reinflation after OLV in an experimental model. Here, using a porcine model, the authors compared BVV with CMV during OLV to assess gas exchange and respiratory mechanics. METHODS: Eight pigs (25-30 kg) were studied in each of two groups. After induction of anesthesia-tidal volume 12 ml/kg with CMV and surgical intervention-tidal volume was reduced to 9 ml/kg. OLV was initiated with an endobronchial blocker, and the animals were randomly allocated to either continue CMV or switch to BVV for 90 min. After OLV, a recruitment maneuver was undertaken, and both lungs were ventilated for a further 60 min. At predetermined intervals, hemodynamics, respiratory gases (arterial, venous, and end-tidal samples) and mechanics (airway pressures, static and dynamic compliances) were measured. Derived indices (pulmonary vascular resistance, shunt fraction, and dead space ventilation) were calculated. RESULTS: By 15 min of OLV, arterial oxygen tension was greater in the BVV group (group x time interaction, P = 0.003), and shunt fraction was lower with BVV from 30 to 90 min (group effect, P = 0.0004). From 60 to 90 min, arterial carbon dioxide tension was lower with BVV (group x time interaction, P = 0.0001) and dead space ventilation was less from 60 to 90 min (group x time interaction, P = 0.0001). Static compliance was greater by 60 min of BVV and remained greater during return to ventilation of both lungs (group effect, P = 0.0001). CONCLUSIONS: In this model of OLV, BVV resulted in superior gas exchange and respiratory mechanics when compared with CMV. Improved static compliance persisted with restoration of two-lung ventilation.

Animals↗

PubMed1995

Psychological factors related to the prevalence of temporomandibular joint sounds.

This study focuses on the association between psychological factors and TMJ sounds, and the most suitable research design to establish this relation. A traditional research design is simulated to demonstrate how self-report may bias findings. A refined design is presented to obtain unbiased estimates of the role of psychological variables. In the 'naïve' design the importance of psychological variables was overestimated and the role of physiological variables was underestimated. It was concluded that future studies in the aetiology of TMJ clicking should abandon the use of self-report as a proxy for objective findings. With the refined design it was found that psychological factors play only a minor role in the prevalence of TMJ sounds. Findings do not support speculation about mechanisms that relate psychological factors to the presence of TMJ sounds.

Adaptation, Psychological↗

PubMed1981

Adenosine deaminase polymorphism. Associations at clinical level suggest a role in cell functions and immune reactions.

It is well known that subjects homozygous for a rare silent allele of ADA may experience a severe combined immunodeficiency. By analogy we have investigated the possible relationship of normal ADA polymorphism with some situations, such as reproductive defects and fetomaternal interactions, in which immunological mechanisms may play an important role. A total of 572 consecutive newborns, 93 consecutive low birthweight infants, 46 couples with unexplained habitual abortion, and 24 couples with unexplained sterility were studied. The proportion of ADA 2-1 phenotype was reduced in couples with reproductive defects. In the sample of consecutive newborns the proportion of ABO incompatible babies was higher among ADA 2-1 than among ADA 1 types. ADA 2-1 phenotype was also associated with a reduction in the variability of gestational length. These associations were much more marked among male than among female babies. The proportion of ADA 2-1 was significantly lower in low birthweight infants than in the consecutively studied infants and normal adults. The present data suggest that biochemical variability resulting from the normal ADA polymorphism may be, at least in part, responsible for the variability of some immunological functions and related physiological variables and pathological conditions. They also provide evidence in favour of a selective advantage of ADA heterozygotes.

ABO Blood-Group System↗

PubMed2003

Association between course of study at university and cause-specific mortality.

Although socioeconomic position is clearly related to mortality and one measure of this is length of education, it is not known whether the choice of course at university determines future health. We therefore investigated the association between faculty of study and all-cause and cause-specific mortality in a prospective follow-up of male students who underwent health examinations while attending Glasgow University from 1948 to 1968. Among the 9887 (84%) alumni traced by means of the NHS Central Register, 8367 (85%) had full data on important potential confounding variables; 939 of these men had died. Physiological variables differed little between students from the various faculties. Medical students were most likely to come from affluent social backgrounds and, after law students, were most likely to be smokers. Compared with former medical students, former arts and law students had excess all-cause and cardiovascular disease mortality, while science and engineering alumni had similar risks. Former medical students had lower lung cancer mortality than other alumni but higher mortality from alcohol-related causes including accidents, suicide and violence. The lower mortality risks observed among former medical and engineering students may be due to their better employment prospects and healthier lifestyle behaviours, although the high mortality from alcohol-related causes among former medical students underscores the complexity of choice of health behaviour. The findings point to the potential for disease prevention among the large proportion of the population who now have third-level education.

Adolescent↗

PubMedDate not supplied

Some problems of night and shift work: Is the physiological cost of long-lasting standard work the same at night as in daytime?

Physiological reactions to long-lasting physical work performed at different times of day were measured in 20 healthy men. Circadian variations in physiologic variables have been shown which indicated higher physiological cost, of night work. The conclusions providing the base for establishing the criteria and guiding principles for shift work are discussed.

Adult↗

PubMed1976

Relation between functional disturbances of the masticatory system and some anthropometric, physiological and psychological variables in young Swedish men.

The relation between functional disturbances of the masticatory system and anthropometric, physiological and psychological variables was studied in 248 Swedish men, aged 18-25 years. No physiological variables and only a few anthropometric variables were found to be correlated with symptoms of functional disorders or to the state of the dentition. Thus, for example, face height was greater in the presence than in the absence of disturbances of the occlusion (mainly occlusal interferences). The psychological variables were found to be most closely correlated with symptoms of functional disorders and the state of the dentition. Men with clinical dysfunction had a lower general level of intelligence than men without. Social adaptation at school was poor in those who reported parafunctions. Men with parafunctions, frequent headache, general muscle and joint symptoms and balancing side interferences had low emotional stability compared with those without such symptoms. Individuals completely free from symptoms of functional disturbances had high emotional stability.

Adolescent↗

PubMed1983

Psychosomatic factors involved in the process of cancerogenesis. Preliminary results of the Yugoslav prospective study.

In a Yugoslav village, psychosocial, anamnestic medical, and pathophysiological data were recorded for 1,353 persons in a longitudinal study. The role of psychosocial stress in carcinogenesis, as far as we have investigated it, may be described as follows: (1) Psychosocial stress in terms of high hopelessness, high antiemotionality, etc. has a strong relevance for cancer incidence which does not act via one of our physiological variables associated with cancer. This follows from the results of our multivariate analysis. (2) Psychosocial stress is substantially associated with a low lymphocyte percentage, which in turn is a relatively strong risk factor for cancer. (3) Psychosocial stress is relatively weakly associated with the cholesterol minimum; but apart from the fact that the cholesterol characteristics of cancer subjects are more marked descriptively under stress conditions, psychosocial stress significantly enhances the efficacy of the most important physiological risk variables for cancer.

Adult↗

PubMed2005

Modeling physiological and anthropometric variables known to vary with body size and other confounding variables.

This review explores the most appropriate methods of identifying population differences in physiological and anthropometric variables known to differ with body size and other confounding variables. We shall provide an overview of such problems from a historical point of view. We shall then give some guidelines as to the choice of body-size covariates as well as other confounding variables, and show how these might be incorporated into the model, depending on the physiological dependent variable and the nature of the population being studied. We shall also recommend appropriate goodness-of-fit statistics that will enable researchers to confirm the most appropriate choice of model, including, for example, how to compare proportional allometric models with the equivalent linear or additive polynomial models. We shall also discuss alternative body-size scaling variables (height, fat-free mass, body surface area, and projected area of skeletal bone), and whether empirical vs. theoretical scaling methodologies should be reported. We shall offer some cautionary advice (limitations) when interpreting the parameters obtained when fitting proportional power function or allometric models, due to the fact that human physiques are not geometrically similar to each other. In conclusion, a variety of different models will be identified to describe physiological and anthropometric variables known to vary with body size and other confounding variables. These include simple ratio standards (e.g., per body mass ratios), linear and additive polynomial models, and proportional allometric or power function models. Proportional allometric models are shown to be superior to either simple ratio standards or linear and additive polynomial models for a variety of different reasons. These include: 1) providing biologically interpretable models that yield sensible estimates within and beyond the range of data; and 2) providing a superior fit based on the Akaike information criterion (AIC), Bayes information criterion (BIC), or maximum log-likelihood criteria (resulting in a smaller error variance). As such, these models will also: 3) naturally lead to a more powerful analysis-of-covariance test of significance, which will 4) subsequently lead to more correct conclusions when investigating population (epidemiological) or experimental differences in physiological and anthropometric variables known to vary with body size.

Anthropometry↗

PubMed2004

Evaluation of perennial ryegrass straw as a forage source for ruminants.

Two experiments were conducted to evaluate perennial ryegrass straw as a forage source for ruminants. Experiment 1 evaluated digestion and physiological variables in steers offered perennial ryegrass straw containing increasing levels of ergot alkaloid, lolitrem B. Sixteen ruminally cannulated Angus x Hereford steers (231+/-2 kg BW) were blocked by weight and assigned randomly to one of four treatments. Steers were provided perennial ryegrass straw at 120% of the previous 5-d average intake. Before straw feeding, soybean meal was provided (0.1% BW; CP basis) to meet the estimated requirement for degradable intake protein. Low (L) and high (H) lolitrem B straws (<100 and 1,550 ppb, respectively; DM basis) were used to formulate treatment diets: 100% L; 67% L:33% H; 33% L:67% H; 100% H (DM basis). Intake and digestibility of DM and OM, and ruminal pH, total VFA, and NH3-N were not affected by increasing lolitrem B concentration. Ruminal indigestible ADF (IADF) fill increased linearly (P = 0.01) and IADF passage rate decreased linearly (P = 0.04) as lolitrem B increased. Experiment 2 evaluated performance and production by 72 Angus x Hereford cows (539+/-5 kg BW) consuming perennial ryegrass straw containing increasing lolitrem B during the last third of gestation. Cows were blocked by body condition score and randomly assigned to one of three treatments. Cows were provided perennial ryegrass straw ad libitum and supplemented with soybean meal (0.1% BW; CP basis) to meet the estimated requirement for degradable intake protein. Mixtures of a L and H lolitrem B straw (467 and 2,017 ppb, respectively) were used to formulate treatment diets: 100% L, 50% L:50% H, 100% H (DM basis). Thirteen of 24 cows on the 100% H treatment exhibited signs of ryegrass staggers and were removed from the study; nevertheless, lolitrem B concentration did not influence pre- or postcalving weight or body condition score change. These data suggest that feeding perennial ryegrass straw containing up to 1,550 ppb lolitrem B (DM basis) did not adversely affect nutrient digestion or physiological response variables in steers. However, providing straw with a lolitrem B concentration of approximately 2,000 ppb (DM basis) resulted in 54% of cows exhibiting signs of ryegrass staggers. These data suggest that blending straws with a high (>2,000 ppb) and low (<500 ppb) concentration of lolitrem B can be a successful management practice.

Animal Feed↗

PubMed1984

Model referenced method of evoked potential analysis.

We have described a method for identifying component wave forms of evoked potentials by reference to a model of the dynamic behavior of neuronal systems. The method parsimoniously reproduces measured data and provides a means for utilizing a priori information from sets of experimental data to discriminate between experimental variables. The method appears successful in quantifying the physiologic variability in the amplitude, shape and latency of EP component wave forms.

Adolescent↗

PubMedDate not supplied

Perception of effort at low and moderate intensity exercise in survivors of childhood acute lymphoblastic leukaemia.

OBJECTIVE: The study examined the degree to which male and female survivors of acute lymphoblastic leukaemia (ALL) perceive effort at low and moderate intensity exercise in association with related physiological variables. MATERIALS AND METHODS: Participants were 67 children. Thirty-five (14 boys and 21 girls) were long-time survivors of ALL and 32 (18 boys and 14 girls) were control subjects. The Children's Effort Rating Table (CERT) was used to measure whole-body perceived exertion at low and moderate intensity exercise. Peak oxygen uptake was measured using a motorized treadmill. CERT and physiological data were analysed using 2 x 2 mixed analyses of variance, appropriate t-tests and coefficients of correlation. RESULTS: In absolute terms, boys treated for ALL found perception of effort to be more strenuous at both low (3.9 vs. 3.5 units) and moderate (6.1 vs. 5.3 units) intensity exercise than control subjects, although differences were not significant (p > 0.05); girls treated for ALL found perception of effort to be the same as controls at low intensity exercise (3.1 vs. 3.1 units) but slightly higher than controls at moderate intensity exercise (5.6 vs. 5.2 units); neither of these differences were significant (p > 0.05). When CERT values were adjusted for (.-)VO(2) peak (%) and heart rate (HR) peak (%) differences remained non-significant. There were no significant interactions (Intensity x Group) in males, but the interaction for (.-)VO(2) peak (%) was significant in females (p < 0.05). The main effect for Intensity (low and moderate) was significant for all variables in boys and girls (p < 0.0001). The main effect for Group (ALL and controls) identified significantly greater absolute (b.p.m.) and relative (%) HR values in ALL boys at low and moderate intensity exercise. In female ALL and control subjects the interaction (Intensity x Group) distinguished between (.-)VO(2) peak (%) at moderate intensity exercise and HR peak (%) at low and moderate intensity exercise. Coefficients of correlation between perceived effort and (.-)VO(2) peak (%) in boys and girls were low to high (0.28-0.76), and between absolute and relative HR were also low to high (0.33-0.73). There were low correlations between time 'off therapy' and perceived effort, (.-)VO(2) peak (%) and HR peak (%) (-0.003 to -0.49). CONCLUSION: It was concluded that perception of effort in survivors of ALL at low and moderate intensity exercise was the same as that of control subjects. Correlations between perceived effort and physiological variables at moderate exercise were low to high, while those between perceived effort and time from treatment were generally weak.

Analysis of Variance↗

PubMed2003

Serum cholesterol levels and stressor controllability in rats.

Whether an organism can control a stressful event is often an important variable determining the impact of the event on physiology and behavior. Numerous behavioral and physiological variables are more adversely affected by uncontrollable stress. The present experiment with rat subjects compared the effect of controllable stress (escape conditioning) or uncontrollable stress (yoked control group) vs. home cage controls on total cholesterol, as well as high-density lipoprotein (HDL) and low/very-low density lipoprotein (LDL/VLDL) serum cholesterol. Results indicated that both stressed groups had higher total and LDL/VLDL cholesterol levels than home cage controls. No group differences were observed with HDL cholesterol. The escape and yoked control subjects did not differ from each other in any dependent measure. Results are discussed in terms of the probable mediators of stress-induced cholesterol increases, and the fact that these mediators may be insensitive to stressor controllability.

Adaptation, Physiological↗

PubMed1997

Predictors of natural killer cell-mediated cytotoxicity deficiency in advanced heart failure secondary to either ischemic or idiopathic dilated cardiomyopathy.

The effect of psychologic variables (situational emotional state and psychiatric diagnosis) and physiologic variables (plasma norepinephrine, decreased cardiac exercise capacity, and elevated pulmonary capillary wedge pressure) on natural killer cell activity was evaluated in 19 patients with advanced heart failure of ischemic or idiopathic origin. Only peak exercise capacity was independently predictive of natural killer cell deficiency.

Cardiomyopathy, Dilated↗

PubMed2002

The effects of an exercise physiology program on physical fitness variables, body satisfaction, and physiology knowledge.

This study was performed to determine the effects of an exercise physiology program on physical fitness, body satisfaction, and knowledge. A total of 161 students (mean age = 16.5 +/- 0.89 years) of the Coral Gables Senior High School served as the experimental group volunteers, whereas 33 students enrolled in a standard biology course served as the control group (mean age = 15.61 +/- 0.84 years). The experimental group received exercise physiology theory coupled with active aerobic and resistance exercise. Age (p = 0.0001) and lean body mass (p = 0.023) were the only physical characteristics significantly greater in the experimental group at pretesting. An analysis of covariance controlling for pretest values showed better results in the experimental compared with the control group for sit and reach (p = 0.008), step test, recovery heart rate (p = 0.0002), overhead press (p = 0.002), bench press (p = 0.017), leg press (p = 0.012), sit-ups (p = 0.001), body satisfaction (p = 0.0009), and physiology knowledge (p = 0.0001) at posttesting. Findings indicated that a biology curriculum integrated with exercise physiology theory and exercise activities may result in significant improvements in physical fitness, body size satisfaction, and physiology knowledge in high school adolescents.

Adolescent↗