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Results for “physiologic variables”

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PubMedDate not supplied

Comparison of chloral hydrate, meperidine, and hydroxyzine to midazolam regimens for oral sedation of pediatric dental patients.

PURPOSE: The purpose of this retrospective study was to compare the effects of oral administration of a combination of chloral hydrate (CH) 25 mg/kg, hydroxyzine (H) 1 mg/kg, and meperidine (M) 1 mg/kg to midazolam 0.65 mg/kg using 50% nitrous oxide (N2O) on behavioral and physiological parameters of young children sedated for dental procedures. Factors associated with sedation effectiveness were identified, including age, preoperative behavior, and type of procedure. METHODS: Records of 116 sedation sessions of 66 healthy, uncooperative children ages 24 to 60 months at The University of Iowa Centers for Disabilities and Development were reviewed. Patients received 1 of the 2 regimens. Intraoperative behavior was rated using a dichotomous scale. Physiological variables including heart rate and oxygen saturation were recorded at baseline and at 10-minute intervals of the session. Data were analyzed using SPSS Version 9. RESULTS: Overall, 81 % of sessions were rated successful. Sedation sessions using CH+H+M combination had significantly higher success rate (P<.01, odds ratio=3.38, 95% confidence interval= 1.06 to 7.15) compared to sessions with midazolam. Sedation success was not associated with age, preoperative behavior, or type of dental procedure performed. Physiological variables were within the normal range for both regimens, although midazolam regimen recorded higher heart rates. CONCLUSIONS: CH+H+M combination using 25 mg/kg CH resulted in significantly more effective sedation sessions compared to midazolam. Both regimens used 50% N2O and were found to be safe.

Anesthesia, Dental↗

PubMed1997

[The classification of the severely and multiply injured--what has been established?].

Among the numerous scores available for the quantitative evaluation of injury severity, only few have proved themselves effective in clinical practice. The "Revised Trauma Score"--based on physiological variables--is the most widespread in preclinical use. The "Injury Severity Score"--based on anatomical data--is the most accepted for defined indices. However, a combination of the two, known as the "Trauma and Injury Severity Score (TRISS)", represents an international standard for quality control. Recent experience with TRISS in central Europe has shown that an increasing number of patients cannot be registered due to missing data. One reason for this is the intense preclinical treatment and its influence on physiological variables. The practicability of this method for quality control--combined with additional efforts--must be questioned in Germany. A score system based, for example, on the obligatory score of the "International Classification of Diseases", might be a good alternative with less effort required for each patient. Further investigations are necessary, however, before any final decisions are made.

Acute Disease↗

PubMedDate not supplied

Association between bispectral analysis and level of conscious sedation of pediatric dental patients.

PURPOSE: This preliminary investigation evaluated the associations among multiple factors designed to measure depth of sedation, such as changes in the patient's electroencephalogram (EEG) via a bispectral analysis (BIS), other physiological variables, observed behaviors and clinical assessment of sedation levels consistent with the American Academy of Pediatric Dentistry (AAPD) sedation guidelines. METHODS: Thirty-four healthy pediatric patients between three to six years of age were enrolled in this institutionally approved study. All children required dental restorations and were uncooperative. The children received a routine oral sedation regimen used in our clinic consisting of chloral hydrate, meperidine, and hydroxyzine that varied in dose for each child. Intraoperatively, nitrous oxide/oxygen was also administered. Physiological variables including oxygen saturation, blood pressure and heart rate were recorded in compliance with AAPD sedation guidelines. The behavior and levels of sedation consistent with AAPD guidelines were also recorded. The BIS monitor was used to obtain EEG information. RESULTS: Useful data were recorded from 21 patients. The mean age and weight of the children were 46.1 +/- 10 months and 16.1 +/- 5 kgs, respectively. The results show a significant association between observed patient behavior and the AAPD levels of sedation (chi2 = 105.1, df = 6, P< 0.0001), between levels of sedation and behavior as a function of 12 time-oriented periods during treatment, (chi2=41.90, df=22, P<0.005 and chi2=48.0, df=33, P=0.04, respectively) and between BIS readings as a function of both level of sedation and behavior (chi2=105.1, df=6, P<0.001 and chi2=28.5, df = 18, P< 0.05, respectively). CONCLUSIONS: There appears to be a significant association between observed patient behaviors during sedation and levels of sedation as measured by BIS and AAPD sedation guidelines. The study also showed that, under treatment conditions used in this study, BIS does not appear to be a more valid means of monitoring sedation depth than the current commonly accepted methods.

Analysis of Variance↗

PubMed2005

Simplified PRISM III score and outcome in the pediatric intensive care unit.

BACKGROUND: To evaluate the association of the PRISM III (pediatric risk of mortality) score with the infant outcome in the pediatric intensive care unit (PICU), and to determine if this score could be simplified. METHODS: A prospective cohort study was carried out with 170 infants who were consecutively admitted to the PICU. The PRISM III score with 17 physiologic variables was performed during the first 8 h of admission to the unit. Statistical analysis was done with logistic regression, odds ratios (OR) with 95% confidence intervals (95% CI), and receiver operating curve. The Alfa value was set at 0.05. RESULTS: There were 42 deaths (24.7%). The two main causes of death were septic shock (28.6%) and head trauma (16.7%). The PRISM III score had a sensitivity of 0.71, and a specificity of 0.64 as a mortality predictor. Out of the 17 physiologic variables only four of them were significant: abnormal pupillary reflexes OR 9.9 (95% CI, 3.5-28.4), acidosis OR 3.1 (95% CI, 2.0-4.9), blood urea nitrogen concentration OR 1.03 (95% CI, 1.01-1.04), and white blood cell count OR 1.02 (95% CI, 1.01-1.03). The whole logistic regression model had a coefficient of determination R(2) = 0.219, P < 0.001. CONCLUSIONS: In this setting, the PRISM III score had good sensitivity and specificity to predict mortality. This score could be simplified using only the four variables that were significant in this study. This modified PRISM III score could reduce the cost of patient care especially in developing countries PICU.

Cause of Death↗

PubMed2003

Effects of hypertonic/hyperoncotic treatment after rat cortical vein occlusion.

OBJECTIVE: To examine the effects of hypertonic/hyperoncotic treatment on physiologic variables and regional cerebral blood flow and to test its neuroprotective efficiency in a model of permanent venous ischemia. DESIGN: Randomized prospective study. SETTING: University research institute. SUBJECTS: Adult male Wistar rats, weighing 359 +/- 54 g (n = 38). INTERVENTIONS: Rats were subjected to photochemical occlusion of two adjacent cortical veins. A randomized infusion with vehicle (0.9% NaCl), 10% hydroxyethyl starch 200,000 (HES), or 7.5% saline plus 10% hydroxyethyl starch 200,000 (HHES) was started 30 mins after two-vein occlusion. Effects on physiologic variables and regional cerebral blood flow (assessed by laser Doppler flowmetry) were studied up to 120 mins after two-vein occlusion. Two days after occlusion, the brains were removed for histologic evaluation. MEASUREMENTS AND MAIN RESULTS: After occlusion, regional cerebral blood flow decreased by 50%, significantly in all groups (from 47.3 +/- 3 to 22.2 +/- 2.2 laser Doppler units). In the vehicle and HES groups, regional cerebral blood flow further decreased to 12.9 +/- 1.9 and 17.8 +/- 2.3 laser Doppler units, respectively. HHES improved regional cerebral blood flow significantly to 27.3 +/- 3.5 laser Doppler units, particularly by reducing no-flow/low-flow areas and reducing infarct size. CONCLUSION: We found that HHES reduced infarct size as a consequence of an improved regional cerebral blood flow and reduced no-flow/low-flow areas in the tissue at risk in the two-vein occlusion model.

Animals↗

PubMed2003

Potential factors related to untrained singing talent: a survey of singing pedagogues.

A national survey was conducted to identify factors associated with untrained singing talent based on perceptions obtained from a homogeneous group of professional singing pedagogues. Survey items included questions related to the perception of singing talent, factors associated with untrained singing talent, and physiological variables that distinguished untrained singing talented individuals from those without obvious singing talent. The survey data suggested that intonation, timbre, and musicality were rated the most important factors associated with the perception of singing talent in an untrained individual. Environmental influences and genetics were rated most important for explaining why one individual would express singing talent and another would not. In addition, the data suggested that abilities related to the control of pitch distinguished untrained talented individuals from those without singing talent more than other physiological variables.

Adult↗

PubMed2000

Trauma in pregnancy.

OBJECTIVE: To determine whether the severity of maternal injury or other maternal and fetal variables will predict the outcome of pregnancy in the injured pregnant patient. PATIENTS AND METHODS: In this retrospective review of pregnant patients hospitalized at a level 1 trauma center from 1986 to 1996, we analyzed the maternal Injury Severity Score, maternal mortality, fetal-neonatal mortality, maternal hypotension, and fetal heart rate. RESULTS: Sixty-one pregnant women were identified who were hospitalized after trauma. The mean +/- SD maternal age was 26.6 +/- 6.6 years. The distribution of trauma per gestational age was 21%, 20%, and 59% for the first, second, and third trimester, respectively. The most common mechanism of injury was motor vehicle crashes. Long-term pregnancy outcome was available in 53 patients (87%). There was 1 maternal death. Fetal-neonatal death occurred in 8 (15%) of 53 pregnancies. Most maternal physiologic variables were not predictors of pregnancy outcome. We were unable to detect a difference in the distribution of Injury Severity Scores between viable and nonviable pregnancies. However, maternal hypotension and low fetal heart rate were common in nonviable pregnancies (P = .02). CONCLUSIONS: Maternal hypotension and fetal heart rate are potential predictors of pregnancy outcome after trauma. Other maternal and fetal physiologic variables are poor measures of fetal well-being and are unable to predict fetal outcome. Fetal-neonatal death does not necessarily correlate with severity of maternal injury.

Abortion, Spontaneous↗

PubMed2003

Fifteen-day cessation of training on selected physiological and performance variables in women runners.

This study examined the effects of a 15-day cessation of training on maximal oxygen consumption and selected physiological variables (maximal heart rate, cardiac output [Q], stroke volume [SV], arteriovenous oxygen difference [(a-v)O2 diff], blood plasma concentration) in 15 women middle-distance competitive runners (.VO2max: 49.8 +/- 1.1 ml.kg(-1).min(-1)). Subjects were randomly assigned to a cessation training (CT, n = 7) or maintenance training (MT, n = 8) group and tested every 5 days. Q was measured by CO2 rebreathing from which SV and (a-v)O2 diff were calculated. No significant changes were found at day 5. After 10 days there was a significant decrement in .VO2max (3.8 ml.kg(-1).min(-1)) in the CT group, being significantly lower than MT but no changes thereafter in any physiological variables. Performance (2,400 m) times did not change for MT but was significantly slower (21.5 +/- 7.1 seconds) for the CT group after 15 days, corresponding to the 7.8% decrease in .VO2max. These findings suggest that in competitive women middle-distance runners, actual performance decrements found after 15 days of CT most likely are due to declines in .VO2max.

Adult↗

PubMed1976

Application of dynamic calorimetry for monitoring fermentation processes.

The rate of heat evolution (kcal/liter-hr) in mycelial fermentations for novobiocin and cellulase production with media containing noncellular solids was measured by an in situ dynamic calorimetric procedure. Thermal data so obtained have proved significant both in monitoring cell concentration during the trophophase (growth phase) and in serving as a physiological variable in the fermentation process. The validity of this technique has been demonstrated by closing the overall material and energy balances. The maintenance energy in a batch fermentation can be calculated by integrating heat evolution data. This integration method is applicable to a fermentation lacking a precise cell growth curve. The maintenance coefficient, obtained for the novobiocin fermentation by Streptomyces niveus, is equal to 0.028 g glucose equivalent/g cell-hr. The production of novobiocin in the idiophase (production phase) also correlates well with the amount of energy catabolized for maintenance and this results in an observed conversion yield of glucose to novobiocin of 11.8 mg of novobiocin produced per gram of glucose catabolized. A new physiological variable, kilocalories of heat evolved per millimole of oxygen consumed, has been proposed to monitor the state of cells during the fermentation. This method may provide a simple way to monitor on-line shifts in the efficiency of cell respiration and changes in growth yields during a microbial process.

Calorimetry↗

PubMed1999

Social stress of variable intensity: physiological and behavioral consequences.

Stress effects in humans depend on stress type, intensity, and duration. Animal models of social stress serve as good ways to mimic stress experienced in humans. However, the available stress paradigms pay little attention to the relationship between the intensity and the type of social stressors. The aim of the present work is to study behavioral and endocrinological consequences of social stress by varying the intensity and type of agonistic social contacts. Subjects were exposed to the attacks of an experienced fighter resident rat once a day for 4 consecutive days. Mild versus strong effects were studied by varying the length of daily confrontations (30 min vs. 4 h). The type of social confrontations was varied by ceasing or maintaining sensory contacts among contestants between encounters. Endocrinological variables were measured on the 5th day. Anxiety was assessed by means of the elevated plus-maze. The stress state depended on the length of daily encounters: 30-min encounters did not, whereas 4-h encounters did result in weight loss and chronic elevation of plasma corticosterone. The type of contacts between subjects and dominants also affected the resulting stress state: adrenal hypertrophy was obtained only when contacts between contestants were maintained between encounters. Although the mildest stress procedure (30-min encounters on 4 consecutive days) did not affect endocrinological variables, it resulted in subtle behavioral modifications that changed the anxiety-related effects of additional acute stressors. Thus, anxiety-related behavioral changes resulting from repeated mild stressors may be hidden factors that can have long-term consequences on the development of anxiety-like behavioral deficits. Results outline the necessity of studying the effects of social stressors of different intensities and different types.

Adrenal Glands↗

PubMed1998

A comparison among animal models of acute lung injury.

OBJECTIVES: To compare four widely used animal models of acute lung injury and to determine the changes in physiologic variables associated with each model. DESIGN: A prospective, controlled animal study. SETTING: An animal laboratory of a university-affiliated children's hospital. SUBJECTS: Four groups of anesthetized, paralyzed, and ventilated young Yorkshire pigs, weighing 35 to 45 kg. INTERVENTIONS: Acute lung injury was generated by four different methods: a) intrapulmonary arterial infusion of endotoxin of Escherichia colt; b) bronchoalveolar instillation of 0.05N of hydrochloric acid; c) repeated bronchoalveolar warm saline lavage; and d) intrapulmonary arterial infusion of oleic acid. After each acute lung injury procedure, the temporal changes in various physiologic variables were measured, starting at 60 mins and at 15-min intervals thereafter for a total of 165 mins. Systemic and mixed venous serum immunoreactive tumor necrosis factor (TNF)-alpha concentrations were also measured at the same time points. Analysis of variance for repeated measures was employed to determine the absolute and relative significance of the changes observed. MEASUREMENTS AND MAIN RESULTS: Systemic and mixed venous immunoreactive TNF-alpha did not change following any of the acute lung injury procedures. The animals' heart rates and systemic vascular resistances also did not change. Hydrochloric acid instillation as well as bronchoalveolar lavage resulted in significant hypoxemia with no other hemodynamic effects. Endotoxin infusion did not result in hypoxemia but caused significant increases in mean pulmonary arterial pressure and pulmonary vascular resistance and decreases in mean arterial pressure and cardiac output. Oleic acid infusion resulted in a marked hypoxemia with a pronounced increase in mean pulmonary arterial pressure and pulmonary vascular resistance. It also markedly reduced the mean arterial pressure, cardiac output, and the mixed venous PO2. CONCLUSIONS: The surfactant depletion and hydrochloric acid instillation models produce acute hypoxemia in an otherwise hemodynamically stable animal. A brief endotoxin infusion provides a model for cardiovascular instability and pulmonary hypertension but fails to produce hypoxemia in the pig. The oleic acid infusion creates a model of marked cardiovascular instability, pulmonary hypertension, and profound hypoxemia. However, none of the acute lung injury models described was associated with the production of tumor necrosis factor.

Animals↗

PubMed2004

Pedalling rate affects endurance performance during high-intensity cycling.

The purpose of this study into high-intensity cycling was to: (1) test the hypothesis that endurance time is longest at a freely chosen pedalling rate (FCPR), compared to pedalling rates 25% lower (FCPR-25) and higher (FCPR+25) than FCPR, and (2) investigate how physiological variables, such as muscle fibre type composition and power reserve, relate to endurance time. Twenty males underwent testing to determine their maximal oxygen uptake (VO(2max)), power output corresponding to 90% of VO(2max) at 80 rpm (W90), FCPR at W90, percentage of slow twitch muscle fibres (% MHC I), maximal leg power, and endurance time at W90 with FCPR-25, FCPR, and FCPR+25. Power reserve was calculated as the difference between applied power output at a given pedalling rate and peak crank power at this same pedalling rate. W90 was 325 (47) W. FCPR at W90 was 78 (11) rpm, resulting in FCPR-25 being 59 (8) rpm and FCPR+25 being 98 (13) rpm. Endurance time at W90(FCPR+25) [441 (188) s] was significantly shorter than at W90(FCPR) [589 (232) s] and W90(FCPR-25) [547 (170) s]. Metabolic responses such as VO(2) and blood lactate concentration were generally higher at W90(FCPR+25) than at W90(FCPR-25) and W90(FCPR). Endurance time was negatively related to VO(2max), W90 and % MHC I, while positively related to power reserve. In conclusion, at group level, endurance time was longer at FCPR and at a pedalling rate 25% lower compared to a pedalling rate 25% higher than FCPR. Further, inter-individual physiological variables were of significance for endurance time, % MHC I showing a negative and power reserve a positive relationship.

Adaptation, Physiological↗

PubMedDate not supplied

Reduction in skin reactions to histamine after a hypnotic procedure.

This study sought to test whether a cognitive-hypnotic intervention could be used to decrease skin reactivity to histamine and whether hypnotizability, physiological variables, attitudes, and mood would influence the size of the skin weals. Thirty eight subjects undertook three individual laboratory sessions; a pretest session to determine sensitivity to histamine, a control session, and an intervention session during which the subject experienced a cognitive-hypnotic procedure involving imagination and visualization. Compared with the control session, most subjects (32 of 38) decreased the size of their weals measured during the intervention session, and the differences between the weal sizes produced in the two sessions were highly significant (N = 38; t = 4.90; p < .0001). Mood and physiological variables but not hypnotizability scores proved to be effective in explaining the skin test variance and in predicting weal size change. Feelings of irritability and tension and higher blood pressure readings were associated with less change in weal size (i.e., a continuation of reactivity similar to that found in the control session without the cognitive-hypnotic intervention), and peacefulness and a lower blood pressure were associated with less skin reactivity during the intervention. This study has shown highly significant results in reducing skin sensitivity to histamine using a cognitive-hypnotic technique, which indicates some promise for extending this work into the clinical area.

Adolescent↗

PubMed2001

Esmolol promotes electroencephalographic burst suppression during propofol/alfentanil anesthesia.

UNLABELLED: This study examined the effects of an esmolol infusion on the electroencephalogram during propofol/alfentanil IV anesthesia. After informed consent, 20 patients were randomly assigned into four groups on the basis of two target alfentanil concentrations (alfentanil 50 or 150 ng/mL) and of a saline or esmolol infusion. Bispectral index (BIS), burst suppression ratio (SR), and physiologic variables were continuously monitored. A 30-min blinded infusion of saline or esmolol was started after establishing a stable baseline and followed by a washout period. The electroencephalogram was significantly suppressed by esmolol (BIS, 37 +/- 6 to 22 +/- 6, 40% decrease [mean +/- SD]; SR, 5 +/- 7 to 67 +/- 23, 13.4-fold increase) compared with baseline in the small-dose alfentanil groups. Discontinuation of esmolol reversed the response. BIS and SR were unaffected by placebo infusion. Twelve-minute to 16-min hysteresis between esmolol administration and the onset of half-maximal cortical suppression was observed. Physiologic variables and serum propofol and alfentanil concentrations were not significantly altered by esmolol. Although the mechanism remains unclear, significant cortical depression and the onset of burst suppression during a stable, computer-controlled propofol/alfentanil anesthetic was associated with esmolol infusion. IMPLICATIONS: This study demonstrated the suppression of cerebral cortical electrical activity after blinded esmolol infusion during propofol/alfentanil anesthesia. A significant lag was noted between infusion and half-maximal effect (12-16 min). Whether esmolol, a metabolite, or a secondary process was responsible for this cortical suppression remains unknown and requires further study.

Adrenergic beta-Antagonists↗

PubMed2000

Comparison of some responses to exercise on the track and the treadmill in French trotters: determination of the optimal treadmill incline.

The purpose of this study was to determine the optimal treadmill slope for trotters to produce the same heart rate and blood lactate responses as on the track during a standardized exercise test. Nine 2-year-old French trotters performed exercise tests on a training track and on a treadmill set at an incline of 0, 2 or 4%. For all horses, track testing was performed on day 1 and then on the treadmill according to a Latin-square design. The track test utilized three steps each of 3 min at speeds of 470, 530, 590 m/min and the same speeds were used on the treadmill. Derived physiological variables such as the speed at a HR of 200 bpm (V(200)) and the speed inducing blood lactate concentrations of 4 mmol/L (V(4)) were calculated. There were significant differences for V(200)and V(4)(P<0.05) between the track and the treadmill data when the treadmill was set at inclines of 0 and 4%, but no significant differences with the treadmill set at a 2% incline. The optimal treadmill incline to reproduce similar responses to those on the track was determined by regression analysis, and was found to be 2.4% for the two most often utilized derived physiological variables, V(4)and V(200).

Animals↗

PubMed2004

Randomized clinical trial comparing conservative and surgical treatment of neurogenic faecal incontinence.

BACKGROUND: The treatment of choice in idiopathic (neurogenic) faecal incontinence is controversial. In a randomized study levatorplasty was compared with anal plug electrostimulation of the pelvic floor with respect to functional outcome and physiological variables. METHODS: Thirty-one patients underwent levatorplasty and 28 anal plug electrostimulation of the pelvic floor over 3 years. The results were evaluated at 3, 12 and 24 months after completion of treatment by means of a validated questionnaire and anorectal manometry and manovolumetry. RESULTS: Incontinence scores were significantly reduced during the entire observation period in both groups (P < 0.001) as was the use of pads (P = 0.003 to P < 0.001). The proportion of patients reporting improvement in physical and social handicap was greater in the levatorplasty group after 3, 12 and 24 months (P = 0.036 to P < 0.001). No significant changes in physiological variables were observed in either group. CONCLUSION: Better results were obtained with levatorplasty than with anal plug electrostimulation of the pelvic floor in patients with idiopathic (neurogenic) faecal incontinence. Levatorplasty should be therefore be considered the treatment of choice for this condition.

Adult↗

PubMed1999

Serial measurements of exhaled nitric oxide during exacerbations of chronic obstructive pulmonary disease.

Excessive inflammation seems important in chronic obstructive pulmonary disease (COPD), particularly during exacerbations of the disease. Exhaled nitric oxide concentration ([NOexh]) is a sensitive marker of bronchial inflammation in asthma; it is unclear if this is also the case in COPD. This study: 1) quantifies [NOexh] in patients with COPD (during an exacerbation and while clinically stable); 2) investigates the response of [NOexh] to i.v. steroid therapy, and its potential relationship with other relevant physiological variables; and 3) assesses the relative contributions of the central and peripheral airways to [NOexh] by collecting exhaled air in two different bags connected in series. Seventeen COPD patients (forced expiratory volume in one second (FEV1) 37.6+/-3.4% of the predicted value (+/-SEM)) hospitalized because of an exacerbation of the disease (arterial oxygen tension (Pa,O2) (7.46+/-0.72 kPa 56.1+/-5.4 mmHg), arterial carbon dioxide tension (Pa,CO2) 5.63+/-0.37 kPa 42.3+/-2.8 mmHg), pH 7.41+/-0.02) and 10 healthy subjects that served as controls were studied. On admission, [NOexh] in COPD was higher than normal (41.0+/-5.1 versus 13.3+/-0.8 parts per billion (ppb), respectively, p<0.001). Despite i.v. steroid therapy, [NOexh] remained elevated throughout recovery (37.9+/-4.8 ppb, p<0.001) until discharge (40.9+/-4.3 ppb, p<0.001). In contrast, when the patients were clinically stable (several months later), [NOexh] was significantly reduced (15.8+/-3.8 ppb, p<0.001), and no longer different from control values. [NOexh] was not related to any of the physiological variables measured during recovery (pulmonary gas exchange) or at discharge (forced spirometry, lung volumes, diffusing capacity). Finally, the contribution of the central and peripheral airways to [NOexh] was not different at any point in time. These results indicate that during exacerbations of chronic obstructive pulmonary disease, the exhaled nitric oxide concentration: 1) is higher than normal; 2) is not reduced acutely by i.v. steroids but is normalized several months after discharge; 3) is unrelated to several physiological indices of disease severity; and 4) appears to be produced homogeneously in central and peripheral airways. Overall, these results are different from those reported in asthma, suggesting that different inflammatory mechanisms are operating in both diseases.

Aged↗

PubMed1996

Mild systolic dysfunction in heart failure (left ventricular ejection fraction >35%): baseline characteristics, prognosis and response to therapy in the Vasodilator in Heart Failure Trials (V-HeFT)

OBJECTIVES: This analysis sought to evaluate the clinical characteristics and outcome in heart failure with mild systolic dysfunction. BACKGROUND: Although heart failure with mild systolic dysfunction occurs commonly, this is an understudied area because clinical trials have usually excluded patients with ejection fraction >35%. METHODS: The 422 patients with left ventricular ejection fraction </=35% were compared with 172 with a left ventricular ejection fraction >35% in the Vasodilator in Heart Failure Trial (V-HeFT I), whereas in V-HeFT-II 554 patients with a left ventricular ejection fraction </=35% were compared with 218 patients with a left ventricular ejection fraction >35% for mortality and clinical care. For a left ventricular ejection fraction >35%, treatment with hydralazine/isosorbide dinitrate was compared with prazosin and placebo therapy in V-HeFT I, and hydralazine/isosorbide dinitrate was compared with enalapril in V-HeFT II for mortality, clinical course and change in physiologic variables: ejection fraction, plasma norepinephrine levels, ventricular tachycardia and echocardiographic variables. RESULTS: In both studies, patients with a left ventricular ejection fraction >35% differed principally in hypertensive history, higher functional capacity and radiographic and echocardiographic cardiac dimension from patients with a left ventricular ejection fraction </=35%, and plasma norepinephrine levels differed in V-HeFT II (p < 0.01). Patients with a left ventricular ejection fraction >35% had a lower cumulative mortality than those with a left ventricular ejection fraction </=35% (p < 0.0001) and less frequent hospital admissions for heart failure (p < 0.014, V-HeFT I; p < 0.005, V-HeFT II). Although cumulative mortality and morbidity did not differ between treatment groups in V-HeFT I, enalapril decreased overall mortality versus hydralazine/isosorbide dinitrate (p < 0.035) in V-HeFT II. For physiologic variables in V-HeFT II, enalapril decreased ventricular tachycardia at follow-up (p < 0.05). CONCLUSIONS: In V-HeFT, heart failure with mild systolic dysfunction was associated with different characteristics and a more favorable prognosis than heart failure with more severe systolic dysfunction. Enalapril decreased overall mortality and sudden death compared with hydralazine/isosorbide dinitrate. Prospective trials are needed to address therapy for heart failure with mild systolic dysfunction.

Aged↗