PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “physiologic variables”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 253 records · Page 14Linked to original sources
PubMed1980

Physiological variables and diabetic status. Findings in Tecumseh, Mich.

A random sample of 568 participants in the Tecumseh, Mich, study, aged 30 to 59 years, was stratified according to blood glucose concentration to select a high proportion of diabetics. Subjects were categorized as overt diabetics, chemical or probable diabetics, or nondiabetics. Diabetic groups and nondiabetics were compared for levels of blood glucose, plasma insulin, serum cholesterol, serum triglyceride, blood pressure, and contours of glucose and insulin curves. Overt diabetics had high mean fasting blood glucose levels. Challenged diabetics had significantly higher concentrations of all variables except cholesterol than nondiabetics, even after adjustment for age and adiposity. Glucose intolerance, adiposity, and sex influenced variables independently. Risk of atherosclerosis is partly attributable to persistent hyperglycemia and related metabolic abnormalities in overt diabetics. Postchallenge diabetics have subtle hyperglycemia but a high frequency of other risk factors. Recent developments suggest that control of blood glucose may become feasible and useful in the prevention of cardiovascular disease in overt and challenged diabetics.

Adult↗
PubMed1980

Effects of social-physiological variables on hypnotic amnesia.

Three experiments assessed the hypothesis that suggested amnesia for a previously learned word list is a function of subjects' interpretations of the ambigous aspects of the amnesia testing situation. By manipulating preliminary instructions concerning interpretations of this situation, subjects who were unselected with respect to hypnotic susceptibility were induced to show either substantial increments or decrements in amnesia. However, subjects high on hypnotic susceptibility ignored preliminary instructions and therefore could not be induced to show decrements in amnesia. Previous findings of more amnesia in hypnotic than in task-motivated subjects were both replicated and reversed by varying subjects' interpretations of the amnesia task. Analyses on the combined data from the three experiments confirmed earlier findings that partial amnesics tend to recall list items in a relatively disorganized fashion. All of these findings are consistent with an inattention hypothesis of suggested amnesia. Theoretical implications for hypnosis research are discussed.

Adolescent↗
PubMed1993

Dyspnea in acute asthma: relationship with other clinical and physiologic variables.

This investigation comprised 58 patients (35 men, mean age 61 years) with acute asthma: mean FEV1 35% of the predicted. The dyspnea score (Borg's scale), breathing rate, pulse rate, blood pressure, FEV1, and PEF were measured on arrival and 30, 60, and 150 minutes after bronchodilator treatment. The level of clinical severity was evaluated using Hedstrand's asthma severity scale. The variables that correlated most closely with dyspnea score at arrival were asthma severity score (r = .51 P < .001) and breathing rate (r = .38, P < .01). The measurement of airflow obstruction with the closest correlation to improvement in dyspnea was FEV1 expressed as a percentage of the pretreatment value (r = -.30* after 30 min, r = -.42** after 60 and r = -.34* after 150 minutes, *P < .05, **P < .01). When examining the intraindividual correlation between the change in dyspnea score and FEV1, a correlation coefficient of more than 0.80 was found in 74% of the patients. Of 18 patients with an increase in FEV1 of less than 20% of baseline, 11 had a decrease in dyspnea score in 3 or more categories. We conclude that there is a discrepancy in the treatment of acute asthma between the effect on dyspnea and airflow obstruction, the clinical implication of which remains to be investigated.

Administration, Inhalation↗
PubMed1989

On the physiology of grooming in a pigtail macaque.

Several functions of social grooming have been proposed, including building affiliative bonds between group members, and reducing tension or anxiety. In this case study, heart rate (HR) of a single adult female pigtail macaque living in a social group was monitored in several behavioral contexts to examine the relationship between grooming and HR level, an indicator of autonomic nervous system activity. The subject was implanted as a part of another study with a multichannel telemetry system which monitored several physiological variables. Physiological and behavioral data were collected over a nine day period. Heart rate during agonistic interactions was significantly higher than during other categories of behavior, and sleep HR significantly lower. When the subject received grooming from others, HR was significantly lower than during self grooming or initiating grooming to others, as well as during other behaviors. HR showed significant declines during bouts of receiving groom (up to 20 bpm), but not during bouts of initiating or self grooming. Following aggression, HR decline was greatest while receiving grooming. There were also HR differences for methods of grooming: stroking but not other methods related to decreases in HR.

Aggression↗
PubMedDate not supplied

Correlates of fatigue in Koreans with chronic lung disease.

OBJECTIVES: The purpose of this study is to explain the multidimensional characteristics of fatigue in Korean persons with chronic lung disease. FRAMEWORK: The Unpleasant Symptom Theory by Lenz et al (1995) provided the theoretical framework for the study. DESIGN: A descriptive correlational study design was used. SAMPLE: A convenience sample of 128 subjects (age = 64.2 +/- 11.3; forced expiratory volume in 1 second percent predicted value = 64.5 +/- 28.8%) was recruited from the outpatient respiratory clinic at a large university hospital in Korea. INSTRUMENTS: Fatigue was measured with the Multidimensional Fatigue Inventory. To identify the factors influencing fatigue, demographic variables, physiological variables, psychological variables, and a situational variable were measured. RESULTS: Subjects had a moderate degree of fatigue in general. The mean score for physical fatigue was relatively higher than that of mental fatigue. Using regression analysis, 48.4% of the variance in overall fatigue was explained by dyspnea and negative mood state. CONCLUSION: This study provides an understanding of multidimensional characteristics of fatigue experienced by Korean persons with chronic lung disease. It suggests that nurses need to include fatigue in their assessments and develop interventions to decrease dyspnea and negative mood in the management of fatigue.

Affect↗
PubMed2005

Pre-hospital endotracheal intubation and positive pressure ventilation is associated with hypotension and decreased survival in hypovolemic trauma patients: an analysis of the National Trauma Data Bank.

BACKGROUND: Studies of pre-hospital endotracheal intubation (ETI) from single EMS systems have shown contradictory results, which may represent local differences in paramedic training and experience. An alternative hypothesis is that positive pressure ventilation increases mortality because positive pressure ventilation causes hypotension in severely injured hypovolemic patients. METHODS: A national sample (National Trauma Data Bank, 1994-2002) was used to minimize effects of local paramedic training and experience. All patients with pre-hospital GCS < 8 (most likely to warrant early ETI) and ISS > 16 (most likely to be hypovolemic) were included. Patients intubated in the field (pre-hospital group, n = 871) and in the emergency department (ED group, n = 6581) were compared. To determine whether pre-hospital ETI was an independent predictor of hypotension and mortality, logistic regression was used to control for potential confounders, including age, ISS, body region injured, AIS scores, pre-hospital IV fluids, and other variables. Physiologic variables were not used, as they may be influenced by ETI and positive pressure ventilation, and were therefore considered outcomes, rather than predictors. RESULTS: Groups were comparable in age, gender, anatomic distribution of injuries, likelihood of at least one severe injury (AIS >3) and other variables, except for head injury (ED 83%, pre-hospital 71%, p < 0.001) and ISS (ED 33 +/- 0.2, pre-hospital 36 +/- 0.6, p < 0.001). Patients intubated in the field were more likely to be hypotensive upon arrival in the ED (SBP < or = 90 mm Hg; ED 33%, pre-hospital 54%, p < 0.001), and had worse survival (ED 45% versus pre-hospital 24%, p < 0.001). Even after controlling for potential confounders, pre-hospital ETI was still an independent predictor of hypotension upon arrival in ED (OR 1.7, 95% CI 1.46 -2.09, p < 0.001) and decreased survival (OR 0.51, 95% C.I. 0.43-0.62, p < 0.001). CONCLUSIONS: Pre-hospital endotracheal intubation in trauma patients is associated with hypotension and decreased survival. This may be mediated by the effect of positive pressure ventilation during hypovolemic states.

Adult↗
PubMed1997

Aerosolized manganese SOD decreases hyperoxic pulmonary injury in primates. I. Physiology and biochemistry.

Prolonged hyperoxia causes lung injury and respiratory failure secondary to oxidative tissue damage mediated, in part, by the superoxide anion. We hypothesized that aerosol treatment with recombinant human manganese superoxide dismutase (rhMnSOD) would attenuate hyperoxic lung damage in primates. Adult baboons were anesthetized and ventilated with 100% oxygen for 96 h or until death. Six animals were treated with aerosolized rhMnSOD (3 mg . kg-1 . day-1 in divided doses), and six control animals did not receive enzyme therapy. Physiological variables were recorded every 12 h, and ventilation-perfusion ratio relationships were evaluated by using the multiple inert-gas elimination technique. After the experiments, surfactant composition and lung edema were measured. We found that rhMnSOD significantly decreased pulmonary shunt fraction (P < 0.01) and preserved arterial oxygenation (P < 0.01) during hyperoxia. The rhMnSOD increased lung phospholipids, phosphatidylcholine and disaturated phosphatidylcholine, and decreased lung edema in this model. Testing of higher and lower doses of MnSOD (1 and 10 mg . kg-1 . day-1) in two other groups of baboons produced variable physiological protection, suggesting a "window" of effective dosage. We conclude that aerosolized MnSOD (3 mg . kg-1 . day-1) affords significant preservation of pulmonary gas exchange during hyperoxic lung injury.

Aerosols↗
PubMed1985

Psychosocial and physiological factors in relation to blood pressure at rest--a study of Swedish men in their upper twenties.

The interrelationships between psychosocial factors, several physiological variables and blood pressure (BP) were investigated in 88 young men (aged 26-32 years) in whom high, intermediate or low BP had been recorded at the age of 18 years. In the original high BP group, venous plasma noradrenaline was normal but adrenaline levels elevated. At the follow-up adrenaline correlated with systolic blood pressure (SBP), and this was also so after controlling for overweight and serum gamma-glutamyltranspeptidase [gamma-GT, a marker for alcohol consumption, which showed an independent association with diastolic blood pressure (DBP)]. Low assertiveness (low scores of verbal and indirect aggression) correlated with high BPs, even after controlling for other psychosocial variables. Several associations between psychosocial job variables and physiological variables were found. Among self-reported job variables, excessive 'demands' and 'bossing others' (but not 'decision latitude' or 'psychosocial conflict') were associated with high SBP. Habitual smoking of cigarettes was not associated with BP at rest, but influenced several associations between psychosocial and physiological variables. Men with high BP at rest and low plasma renin activity (PRA) reported more psychosocial problems at work and lower assertiveness than other groups.

Adult↗
PubMed2004

Viability of Iberian x Meishan F2 newborn pigs. I. Analysis of physiological and vitality variables.

Eight physiological and vitality variables related to the first minutes of the life of Iberian x Meishan F2 piglets were analyzed. Variables included rectal temperature, arterial oxygen saturation, heart rate (all were monitored at birth and 60 min later), time to reach the udder, and time to the first colostrum intake. Litter effect within boar, a random source of variation, influenced all variables, whereas the random boar effect was not significant for heart rate and arterial oxygen saturation at birth and the time to reach the udder. Birth weight influenced rectal temperature at birth (P < 0.01) and 60 min later (P < 0.001), arterial oxygen saturation 1 h after birth (P < 0.05), heart rate 1 h after birth (P < 0.001), time to reach the udder (P < 0.05), and time to the first suckle (P < 0.01), whereas viability score influenced rectal temperatures (at birth and 60 min later; P < 0.001), and time to reach the udder (P < 0.001) and to suckle (P < 0.001). Finally, the order of birth showed significant effects for rectal temperature 1 h after birth (P < 0.001) and time to first colostrum intake (P < 0.001). Correlation coefficients between physiological variables were generally low, with the exception of the ones for rectal temperature 1 h after birth and arterial oxygen saturation 1 h after birth (0.38; P < 0.001), and for rectal temperature at birth and rectal temperature 1 h after birth (0.34; P < 0.001). Times to reach the udder and to suckle were highly correlated (0.67; P < 0.001) and also were moderately and negatively correlated with rectal temperature 1 h after birth (-0.36 and -0.38 respectively; P < 0.001). Heart rates at birth and 1 h later, as well as arterial oxygen saturation at birth and 1 h later, were not correlated, showing that the values at birth do not necessarily provide information about the physiological status of the pig 1 h after birth. The recording of physiological variables, birth weight, and viability score may be useful to identify weak piglets quickly and to establish palliative measures.

Adaptation, Physiological↗
PubMed2003

Moderate hypothermia may be detrimental after traumatic brain injury in fentanyl-anesthetized rats.

OBJECTIVES: To determine whether transient, moderate hypothermia is beneficial after traumatic brain injury in fentanyl-anesthetized rats. DESIGN: Prospective, randomized study. SETTING: University-based animal research facility. SUBJECTS: Adult male Sprague-Dawley rats. INTERVENTIONS: All rats were intubated, mechanically ventilated, and anesthetized with fentanyl (10 microg/kg intravenous bolus and then 50 microg.kg(-1).hr(-1) infusion). Controlled cortical impact was performed to the left parietal cortex, followed immediately by 1 hr of either normothermia (brain temperature 37 +/- 0.5 degrees C) or hypothermia (brain temperature 32 +/- 0.5 degrees C). Hypothermic rats were rewarmed gradually over 1 hr. Fentanyl anesthesia and mechanical ventilation were continued in both groups until the end of rewarming (2 hrs after traumatic brain injury). MEASUREMENTS AND MAIN RESULTS: Histologic assessment performed 72 hrs after traumatic brain injury was the primary outcome variable. Secondary outcome variables were physiologic variables monitored during the first 2 hrs after traumatic brain injury and plasma catecholamine and serum fentanyl concentrations measured at the end of both hypothermia and rewarming (1 and 2 hrs after traumatic brain injury). Contusion volume was larger in hypothermic vs. normothermic rats (44.3 +/- 4.2 vs. 28.6 +/- 4.0 mm, p <.05), but hippocampal neuronal survival did not differ between groups. Physiologic variables did not differ between groups. Plasma dopamine and norepinephrine concentrations were increased at the end of hypothermia in hypothermic (vs. normothermic) rats (p <.05), indicating that hypothermia augmented the systemic stress response. Similarly, serum fentanyl concentrations were higher in hypothermic (vs. normothermic) rats at the end of both hypothermia and rewarming (p <.05), demonstrating that hypothermia reduced the clearance and/or metabolism of fentanyl. CONCLUSIONS: Moderate hypothermia was detrimental after experimental traumatic brain injury in fentanyl-anesthetized rats. Since treatment with hypothermia has provided reliable benefit in experimental traumatic brain injury with inhalational anesthetics, these results indicate that the choice of anesthesia/analgesia after traumatic brain injury may dramatically influence response to other therapeutic interventions, such as hypothermia. Given that narcotics commonly are administered to patients after severe traumatic brain injury, this study may have clinical implications.

Anesthesia, Intravenous↗
PubMedDate not supplied

Physiological markers of smoking and their relation to coronary heart disease. The Lipid Research Clinics Coronary Primary Prevention Trial.

Several physiological variables which have previously been found to be associated with extent of cigarette smoking were investigated in a population selected to be free of existing coronary heart disease yet having high circulating cholesterol levels. Of these variables, white blood cell count had the strongest association with the extent of smoking. The addition of hematocrit and heart rate to white blood cell count strengthened the association. Given these three variables, however, other physiological variables had a minor effect on the association. Finally, the combination of these three physiological variables was more strongly predictive of subsequent coronary heart disease than was self-reported smoking level.

Coronary Disease↗
PubMed2003

Biological variation in variables associated with exercise training.

To be able to identify a training induced change in a certain variable, it is necessary to know the background variation. In this study the coefficient of variation (total, between-subjects, within-subjects), the relative sources of variance (between-subjects and within-subjects), and the critical difference (within-subjects) were estimated in four categories of variables (performance and physiological variables, metabolic and hormonal variables, immunological variables, and mood state variables) in 15 moderately trained male runners measured on three different occasions over a period of 7 weeks. In the performance and physiological variables, 78.9 % of the variance was due to variation between subjects and they had the lowest critical difference (11.9 %). In contrast, the metabolic and hormonal variables had the highest critical difference (59.9 %) and 53.4 % of the variance was due to variations within subjects. The immunological and psychological variables had about two thirds of the variance arising from variation between subjects. However, the critical difference for the immunological variables was high (47.4 %), while it was relatively low for the psychological variables (26.8 %). The low critical difference and variation within subjects of the psychological and in particular the performance and physiological variables indicate that they may be beneficial as primary markers of training induced changes.

Adult↗
PubMed1990

Beyond our means: patterns of variability of physiological traits.

Epidemiologists usually employ measures of variability of physiological traits such as blood pressure and cholesterol only to determine confidence intervals or statistical significance. For evolutionary biologists population variability per se has proven of interest. This article explores the applicability of this perspective to the analysis of human physiology, using data from the Framingham Heart Disease Study and the National Health and Nutrition Examination Surveys. The nonrandom patterns of variability observed suggest that examination of the degree and pattern of heterogeneity within a population may provide information not evident from the analysis of mean values.

Adaptation, Physiological↗