SEARCH · PubMed Health

Results for “Supine Position”

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 451 records · Page 25Linked to original sources

PubMed2007

The effect of different body positions on blood pressure.

AIM: The aim of the present study was to test the effects of different body on BP readings in a Turkish healthy young adults. BACKGROUND: It is known that many factors influence an individual's blood pressure measurement. However, guideliness for accurately measuring blood pressure inconsistently specify that patient's position and they should keep feet flat on the floor. Although there are more information on arm position in blood pressure measurement, surprisingly little information can be found in the literature with respect to the influence of body position on the blood pressure readings in healthy young people. METHODS: A total of 157 healthy young students who had accepted to participate in the study were randomly selected. In all subjects the blood pressure was measured subsequently in four positions: Sitting blood pressure was taken from the left arm, which was flexed at the elbow and supported at the heart level on the chair. After at least one minute of standing, the blood pressure was then taken standing, with the arm supported at the elbow and the cuff at the heart level. After one minute of rest, the blood pressure was subsequently taken supine position. Finally, after one minute the blood pressure was again taken in this last position with supine position with crossed legs. RESULTS: The blood pressure tended to drop in the standing position compared with the sitting, supine and supine with crossed legs. Systolic and diastolic blood pressure was the highest in supine position when compared the other positions. There was a difference between systolic blood pressures and this was statistically significant (P < 0.001) but the difference between diastolic blood pressure was not statistically significant (P > 0.05). All changes in systolic blood pressure were statistically significant except those from supine to supine position with crossed legs. RELEVANCE TO CLINICAL PRACTICE: When assessing blood pressure it is important to take the position of the patient into consideration. Also, blood pressure measurement must be taken in sitting position with the arms supported at the right a trial level.

Adolescent↗

PubMed1997

A motor milestone change noted with a change in sleep position.

OBJECTIVE: To evaluate whether sleeping in the supine position resulted in changes in gross or fine motor developmental milestones observed at routinely scheduled well-child checkups at 4 or 6 months of age. DESIGN: A retrospective chart review. SETTING: One private pediatric practice involving 2 full-time and 2 part-time board-eligible or board-certified pediatricians. SUBJECTS: The study included 343 full-term infants whose weights were appropriate or large for gestational age, had no history of hospitalization other than for normal newborn care, and were examined in the office for their 4-month well-child checkup within 2 weeks of being 4 months old. METHODS: The Denver Developmental Screening Test-Revised was administrated at the 4- and 6-month well-child checkups. The primary sleep positions of the infants were determined by telephone survey, office interview, or letter after the 6-month checkup was completed. Background data collected from the mother for each mother-infant pair included maternal age at the time of birth, parity, and marital status, Medicaid status and ethnicity of the infant, and whether the infant was breast-fed. RESULTS: Infants who slept in the side or supine position were less likely to roll over at the 4-month checkup than infants who slept primarily in the prone position (P < .001). No significant differences were found when comparison by maternal age, parity, or marital status, Medicaid status or ethnicity of the infant, or the use of breast-feeding were considered. Other motor milestones screened did not show statistically significant changes. CONCLUSIONS: Sleep position significantly influences the age of achieving the gross motor developmental milestone of rolling over; infants who sleep in the side or supine position roll over later than infants who sleep in the prone position.

Child Development↗

PubMed1988

[Echographic diagnosis for deep vein thrombosis of the lower extremities].

Echographic examination of the femoral vein was carried out in two positions: first in supine position and then in standing position, in order to make a diagnosis of deep vein thrombosis (DVT) of the lower extremities. The distance between the wall images of the femoral vein was measured on the line passing through the center of the femoral artery and crossing the common tangent line of the femoral artery and vein at right angle, and the ratio of this distance in supine position to that in standing position was named FEMORAL VEIN DISTENSIBILITY INDEX (FVDI). The FVDI was 2.83 +/- 0.83 in control group consisting of 14 healthy subjects, and 1.26 +/- 0.18 in DVT group consisting of 21 patients with 23 legs. There was a statistically significant difference between the two groups (p less than 0.001). No statistical difference of the FVDI was, however, noted between the control group and the diseased group consisting of 19 contralateral, symptom-free legs. And no relation was confirmed between FVDI and venographical findings, namely site and extension of thrombotic occlusion. By introducing the FVDI, which reflects functional hemodynamics of the femoral vein, the echographic diagnosis for DVT has become easier and more accurate, presenting a diagnostic accuracy of 90.6% in this study.

Adult↗

PubMed1979

[Pulmonary function differences in healthy subjects according to postural changes (author's transl)].

The total lung capacity (TLC) and its subdivisions along with the forced spirometric values (FEF25-75 and FEV1) were determined in a group of 44 healthy subjects, composed of 29 women and 15 men. The determinations were carried out in a sitting position and in supine position, breathing air. All the pulmonary volumes diminished when the subject lay down, but the functional residual capacity (FRC) was that which underwent a greater reduction. The residual volume decrease was the only one which did not reach statistically significant levels. Women always showed smaller pulmonary volumes than men. It has been demonstrated that FRC can be exactly measured by means of the closed helium technique. The regression figures of FRC in supine position were determinted for both sexes, with a r = 0,33 (p less than 0,1) in women and r = 0,95 (p less than 0.001) in men. The forced spirometric tests did not undergo any important changes although the reduction of the FEV1 was significant in both sexes. The results obtained were compared with those published by other authors.

Adult↗

PubMed1991

Pulmonary contusion causes long-term respiratory dysfunction with decreased functional residual capacity.

To elucidate the mechanism of persistent dyspnea after blunt chest trauma, we prospectively studied the pulmonary function of 18 patients with blunt chest trauma for 6 months. Nine of the patients had flail chest and 12 had pulmonary contusion (PC). Pulmonary function was evaluated using spirometry, arterial blood gas analysis, chest x-ray studies and CT scans. Functional residual capacity (FRC) remained significantly reduced throughout the 6 months in patients with PC. Such patients experienced a fall in Pao2 when changed from a sitting position to a supine position and they had fibrous changes in the contused lung as demonstrated by CT scans at 6 months after injury. These findings were supported in an additional study of another 20 patients who had suffered PC 1 to 4 years previously. This study demonstrated that pulmonary function recovered within 6 months in patients without PC even with a residual deformity of the thoracic wall caused by flail chest, while patients with PC had decreased FRC and a fall in Pao2 when moved to the supine position even several years after injury. This might be related to the persistent dyspnea seen after blunt chest trauma.

Adult↗

PubMed1992

Maternal cerebral hemodynamics in the supine hypotensive syndrome.

Cerebral hemodynamics were studied in eight nonpregnant women and 24 women in late pregnancy by internal carotid artery velocimetry with a 3.5-MHz continuous-wave Doppler system. Criteria for supine hypotensive syndrome were a mean blood pressure decrease of 15 mmHg and a 2-minute sustained increase in pulse of 20 beats per minute under postural change from the left lateral to supine position. Nonpregnant and normal pregnant controls not meeting these two criteria displayed decreases of 22.9 and 21.7%, respectively, in time-averaged mean peak velocity (mean velocity) in the supine position compared with the left lateral position. Five subjects with subclinical supine hypotensive syndrome who met one of the above criteria showed a 37.0% decrease in internal carotid artery mean velocity in the supine position. Two patients with supine hypotensive syndrome could not tolerate the supine position for more than 6 minutes, at which time internal carotid artery mean velocity fell below 10 cm/second, reverse flow was observed, and they complained of dizziness, nausea, and syncope. Internal carotid artery mean velocity in all women showed no change in the sitting position compared with the left lateral position. These results indicate that the supine position should be avoided in late pregnancy, especially by women with cerebrovascular complications.

Adult↗

PubMed2002

Method to plan, administer, and verify supine craniospinal irradiation.

Craniospinal irradiation remains an important technique in the management of malignancies of the central nervous system. It is technically demanding, with potential for treatment field overlap or gaps to yield unacceptable dosimetric heterogeneity. A method to accurately simulate and verify the three-field junction is described. We use a comfortable supine position to minimize patient movement. The supine position provides airway access by anesthesiology in patients requiring sedation or anesthesia. Virtual simulation is performed with a dedicated computed tomography (CT) simulator. Multiplanar sagittal and coronal CT reconstructions allow visual confirmation of three-field matching at the cervical region. The placement of isocenters for each field, table position, and collimator angles are determined by calculation of field sizes accommodating for beam divergence. At treatment, exact matching of the three fields is assured using the record and verify confirmation of beam collimator settings and rotation, digital couch readouts, and gantry parameters. Mini-verification silver halide (Kodak XV) films (6x6 cm) are placed behind the patient's neck and are exposed by all treatment fields (posterior flash from the lateral cranial fields and entrance from the PA spine field). These films assess field placement accuracy at the junction of these three fields. Finally, placement of radio-opaque markers at the junction is visualized in each clinical portal radiograph. Patients readily accept the supine position as their treatment setup is eased. Field placement using digital couch settings is efficient and accurate. Daily mini-verification films are simple, inexpensive, and allow verification of each treatment field matching. Field placement errors of greater than 1 mm can be readily identified and corrected at subsequent treatment sessions. Virtual simulation and direct junction verification with mini-verification films allow for simple and quantitative evaluation of the junction associated with the three-field craniospinal irradiation technique. The supine patient position does not present any difficulties in field matching or verification.

Cranial Irradiation↗

PubMed1992

Effects of body position and age on membrane diffusing capacity and pulmonary capillary blood volume.

The effects of body position and age on the membrane diffusing capacity (Dm), pulmonary capillary blood volume (Vc), and the single breath carbon monoxide diffusing capacity (Dco) were evaluated in the erect (sitting) and supine positions in 16 normal young men (under 40 years old, younger group) and in 13 older men (over 40 years old, older group). Dm and Vc were estimated by several measurements of the Dco at increasing alveolar oxygen tension (PAO2). The results showed that Dco, Dm, Vc, and Kco (Dco corrected by alveolar volume) decreased with age in both positions. The differences in Dco, VC, and Kco between the two positions (supine minus the erect position) also decreased with age. The mechanisms of the increases in Dco in the supine position remain to be explained but may be due to a change in pulmonary capillary shape from an elliptical (erect position) to a circular configuration (supine position) since Vc increased more than Dm on assuming the supine position. The findings may be of clinical importance since many physicians have attempted to utilize a reduction in the positional change in Dco as a potential marker of disease.

Adult↗

PubMed2005

Determinants of the apnea index in a sleep center population.

We hypothesized that the increased apnea-hypopnea index (AHI) in men compared to women was secondary to an increased proportion of apneas in men as measured by the ratio of the apnea index to the apnea-hypopnea index (AI/AHI ratio), and that the influence of gender was independent of other demographic factors such as body mass index (BMI) and neck circumference (NC). Database analysis of 501 patients (218 men and 283 women) who underwent polysomnography between August 2001 and June 2003 and who were found to have an AHI of at least five events per hour was performed. Respiratory parameters were compared between genders. To correct for differences in demographic parameters, correlations were made between AHI and the AI/AHI ratio and age, BMI, NC, and the percentage time spent in the supine position (%TST-supine) followed by a regression analysis to determine which factors independently predicted these parameters. AHI [women, 26.8 (interquartile range 13.9, 57.0) events per hour vs men, 58.9 (interquartile range 27.7, 105.7) events per hour, p<0.001] and AI/AHI ratio [women, 0.58 (0.36, 0.80) vs men, 0.80 (0.51, 0.95), p<0.001) were higher in men compared to women. The independent predictors of the AHI were male gender, BMI, NC, and the %TST-supine. Independent predictors of the AI/AHI ratio were male gender, BMI, NC, and the percentage of time spent in the supine position. The increased AHI in men is secondary to an increased proportion of apneas in men compared to women and is independent of other potential determinants such as age, BMI, and NC.

Anthropometry↗

PubMed1999

The effect of head orientation on the vestibular evoked potentials to linear acceleration impulses in rats.

OBJECTIVE: To investigate the influence of linear acceleration impulses delivered when the head is held in different static head orientations, on the first wave of the short latency vestibular evoked potential (VsEP). The first wave is the compound action potential of the primary vestibular neurons synchronously activated. BACKGROUND: It has been shown previously that the VsEP elicited in response to linear acceleration is initiated mainly in the otolith organs. These organs are responsive to both dynamic and static linear forces, including gravity. METHODS: VsEPs to linear acceleration stimuli (4g) were recorded when the rats head was oriented so that a) the plane of the utricular macula was aligned with the plane of the stimulus, b) in supine position and c) with the head pitched up and down in various angles with respect to gravity (stimulus-head spatial relation remained constant) as compared to a reference position. RESULTS: With the stimulus aligned with the plane of the utricular macula, the amplitude of the first wave of the L-VsEPs was significantly larger than in the reference position. In the supine position, the amplitude of the first wave was significantly larger and the latency was significantly shorter. The amplitude of the first VsEP wave tended to be larger in the "head up" orientations as compared to the "head down" orientations (not statistically significant). CONCLUSIONS: These results demonstrate the influence of head position and gravity on the VsEPs to linear acceleration impulses, which is in accordance with their otolithic origin.

Acceleration↗

PubMed1982

Effect of postural changes on certain circulatory and respiratory values in the horse.

Certain circulatory and respiratory values were measured in horses in the standing, lateral, and supine positions. Twelve adult horses were kept in the standing position under the influence of glycerol guiacolate. Alterations in position to lateral and dorsal recumbencies were achieved without any further drug administration. The changes from the standing to the lateral position decreased the arterial oxygen tension, but left the arterial carbon dioxide tension unchanged. There was no statistically significant effect of body position on respiratory flow rates or volumes. The shift from the lateral position to the supine position had no statistically significant effect on any of the measured values. It is assumed that the change from the standing to the lateral position results in an increase in ventilation of the uppermost parts of the lung. The perfusion inequalities are due mainly to the effect of gravity of the pulmonary circulation which may result in a decrease in arterial oxygen tension.

Anesthetics↗

PubMed1980

A clinical study on the prolonged antihypertensive effect of clonidine in a sustained-release capsule formulation.

Eight patients with essential hypertension each received a single oral dose of 1 capsule of a sustained-release formulation of 0.25 mg clonidine in the morning for 3 consecutive days. Pulse ratio and blood pressure were measured in the standing and supine positions at specific intervals. After the first day of treatment, a significant decrease in blood pressure lasting 24 hours was recorded for the standing position. In the supine position, there was a progressive decrease in blood pressure which also attained significance on the third day of treatment. There was a progressive and significant reduction in mean arterial pressure from the first to the third day.

Adult↗

PubMed1977

Eustachian tubal function during immersion.

The effects of head-out immersion on active and passive middle ear pressure equilibration were studied in three otologically normal scuba divers. Results were compared with the equilibration capacity recorded in the nonimmersed sitting and supine positions. Head-out immersion had only a minor effect on the ability to equilibrate the middle ear pressure actively during descent; passive ear clearing during ascent was slightly more difficult compared with this capacity in the sitting nonimmersed position. In the supine position ear clearing was significantly more difficult during both ascent and descent, which indicates that it is preferable to assume an upright body posture during exposures to pressure changes in dry pressure chambers. Mechanisms that might influence the ability to equilibrate the middle ears are discussed.

Adult↗

PubMed1995

Why leg crossing? The influence of common postures on abdominal muscle activity.

STUDY DESIGN: Abdominal muscle activity is recorded in the supine position, unconstrained standing, and in the sitting position on an office chair with the use of backrest and armrests, with and without crossed legs. OBJECTIVES: To assess the role of oblique abdominal muscles in relation to the stability of lumbar spine and pelvis in commonly adopted unconstrained postures. SUMMARY OF BACKGROUND DATA: Cross-legged sitting is very common for men and women. No solid evidence exists for either a beneficial or a detrimental effect of this posture. No electromyographic study deals with the activity of abdominal muscles in this commonly adopted unconstrained posture. METHODS: In healthy subjects, electromyographic activity of the rectus abdomini and external and internal oblique abdominals was recorded bilaterally during commonly adopted unconstrained postures. RESULTS: The activity of the internal oblique muscle was significantly higher in the sitting position than in supine position. For the external and internal oblique abdominals, the activity was significantly higher in the standing position than in the sitting position. When sitting, the activity of the oblique abdominals is significantly lowered by crossing the legs in the preferred way (either upper legs cross or ankle on knee). In contrast, the activity of the rectus abdominis is not significantly altered by leg crossing. CONCLUSIONS: From these remarkable findings, we conclude that leg crossing is physiologically valuable. It should be studied whether leg crossing can be implemented in the design of the workplace.

Abdominal Muscles↗

PubMed2006

Postural effects on interstitial fluid pressure in humans.

BACKGROUND: Direct assessment of the effect of postural changes on interstitial fluid pressure (IFP) in the human skin under physiological conditions is important for the understanding of mechanisms involved in diseases resulting in lower limb edema. Previous techniques to measure IFP had limitations of being invasive, and acute measurements were not possible. Here we describe the effect of postural changes on IFP in the skin of the foot using the minimally invasive servonulling technique. RESULTS: Measurements were performed in 12 healthy subjects. IFP (means +/- SD) was significantly higher in the sitting (5.1 +/- 2.9 mm Hg) than in the supine position (-0.3 +/- 3.6 mm Hg, p = 0.04) when measured in the sitting position first. The difference between the sitting and the supine position was not significant when measurements were taken in the supine position first [from 1.0 +/- 4.3 (supine) to 3.6 +/- 6.7 mm Hg (sitting), p = 0.46]. Spontaneous low-frequency pressure fluctuations occurred in 58% of the recordings during sitting, which was almost twice as frequent as in the supine position (33%; p = 0.001), while no effects on lymphatic capillary network extension were observed (p = 0.12). CONCLUSION: Using the servonulling micropressure system, postural effects on IFP can be directly assessed. IFP is higher in the sitting position, but differences are influenced by the time in the upright position.

Adult↗

PubMedDate not supplied

Cardiac size in the supine chestfilm.

The aim of this study was to find a normal value for the cardiac size in the supine position because such a standard is hardly known in the literature. Cardiac size in the erect and supine positions were compared in 165 patients in whom both chest radiographs were performed prior to kidney transplantation. For cardiac size as well as for cardiothoracic ratio (CTR) there is a linear relation between the measured values in the two positions which allows to determine the cardiac size in the supine position from a radiograph taken in the erect position and thus to determine whether cardiac enlargement exists in a supine chest film. A survey of 100 patients without cardiac or pulmonary pathology showed 16 patients with a heart size over 15 cm, the upper limit of normal as established over 20 years ago, which suggests that nowadays a new standard might be set. If so, the upper limit of normal CTR is 0.55 in the erect and 0.58 in the supine position. Two figures are presented to determine cardiac size and CTR in the supine position from the measured values in the erect position and vice versa.

Adolescent↗

PubMedDate not supplied

[Comparison of venous pressure in the external jugular vein and the superior vena cava during anesthesia].

Venous pressure between the external jugular vein (EJV), and the superior caval vein (SCV) was compared in 15 patients, free of cardiorespiratory disease and undergoing abdominal surgery. In each patient data was taken in four different positions: A) anaesthetized patient in supine position and mechanical ventilation; B) anaesthetized patient in Trendelenburg position and mechanical ventilation; C) anaesthetized patient in anti-Trendelenburg and mechanical ventilation, and D) awake patient in supine position and spontaneous ventilation. A short, thick catheter with unique end lumen was used for EJV, and a long catheter from the basilic vein, to the SCV. Significant differences between mean and standard deviations of EJV and SCV were not founded. Linea correlation for the 4 positions was performed (r = 0.97, 0.91, 0.88 and 0.60 respectively) being significant for A-B y C positions. 4.5 cm H2O was the maximal difference obtained between SCV and EJV for A, B and C positions, and 10 cm H2O the maximal difference for the D position. The mean changes between the positions A-B, A-C and A-D was compared and significant differences (p less than or equal to 0.001) for A-C were seen, whereas A-B did not attain significant differences. We conclude that the EJV cannulation, with a short and thick catheter, allow the central venous pressure control during anaesthesia, in supine position, Trendelenburg and anti-Trendelenburg, but not during the recovery.

Abdomen↗

PubMed2003

Changes in intraocular pressure during prolonged (7-day) head-down tilt bedrest.

PURPOSE: To determine the change in intraocular pressure (IOP) due to postural changes in young healthy volunteers. MATERIALS AND METHODS: Intraocular pressure was measured using a calibrated Pulsair noncontact tonometer in both eyes of 25 female volunteers in a sitting position and after 1, 3, and 10 minutes in a supine position. In the second part of the experiment (a 7-day -6 degrees head-down tilt [HDT]), IOP (at 8 am, 12 am and 6 pm) and corneal thickness (12 am) were monitored in 8 female volunteers before, during, and after the HDT period. Blood pressure, hematocrit, plasma volume and osmolality, and plasma catecholamines concentrations were also measured. RESULTS: Intraocular pressure was significantly higher in the supine position (16.1 +/- 3.6 mm Hg) than in the sitting position, with a mean pressure difference of 2.23 +/- 2.9 mm Hg after 1 minute, 0.9 +/- 3 mm Hg after 3 minutes, and 1.9 +/- 3.8 mm Hg after 10 minutes in a supine position (P < 0.001). During the period of HDT, IOP values decreased significantly on the fifth day (13.3 +/- 1.6 mm Hg, P = 0.03) and the seventh day (12.7 +/- 1.7 mm Hg, P = 0.02) when compared with IOP in the supine position (14.26 +/- 2 mm Hg). The corneal thickness increased significantly (P < 0.0001) at day 5 (549.25 +/- 48.7 microm) and day 7 (540.31 +/- 46.9 microm) compared with baseline (532.45 +/- 38.6 microm). Two days after the end of the HDT bedrest, the mean supine IOP significantly increased (14.1 +/- 1.8 mm Hg, P = 0.003) and corneal thickness was similar to that found at baseline. The mean decrease of IOP was positively correlated with that of the plasma volume (-10%, r = 0.61, P = 0.02) and negatively correlated with the mean rise of hematocrit (r = -0.5, P = 0.07), variables that are considered to be indirect measures of plasma dehydration. CONCLUSIONS: During a 7-day HDT bedrest experiment in healthy women, eyes seemed to compensate the moderate rise of IOP described between a sitting and a supine position, and exhibited a slight and progressive average decrease of 1.3 mm Hg. These physiological modifications could be related to an ocular dehydration or to systemic cardiovascular and hormonal variations during bedrest.

Adult↗