Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “REST”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

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

At least 163 records · Page 9Linked to original sources
PubMed1999

Physiological effects of acute and ordinary bed rest conditions on endurance trained volunteers.

The aim of this study was to carry out a comparative study of water balance and water protein composition of the blood during exposure to acute (abrupt restriction of motor activity) and ordinary rigorous bed rest of 7 days. The studies were performed on 30 long distance runners aged 22-25 years old who had a VO2, max of 66 ml kg-1 min-1 on the average. The volunteers were divided into three equal groups: the volunteers in the 1st group were under a normal ambulatory life conditions (control subjects), the volunteers of the 2nd group subjected to an acute bed rest (abrupt restriction of motor activity) regime (acute bed rested subjects) and the volunteers of the 3rd group were submitted to ordinary and rigorous bed rest (rigorous bed rested subjects). All volunteers were on an average of 13.8 km day before taking part in this investigation. The 2nd and 3rd groups of volunteers were kept under a rigorous bed rest regime for 7 days. During the prebed rest period and actual bed rest period plasma volume (PV), total protein and protein fractions (albumins and globulins) and hematocrit were measured. Exposure to acute bed rest conditions induced a significant increase in hematocrit, hemoglobin concentration, protein fractions and marked decrease in (PV) and water balance which were significantly more pronounced than during exposure to ordinary rigorous bed rest. It was concluded that exposure to acute bed rest conditions induces significantly greater changes in water balance and water protein concentration of the blood of endurance trained volunteers than exposure to ordinary rigorous bed rest conditions.

Adaptation, Physiological↗
PubMed2000

Poststress measurements of left ventricular function with gated perfusion SPECT: comparison with resting measurements by using a same-day perfusion-function protocol.

PURPOSE: To investigate the relationship between the development of ischemia during stress testing and the changes in left ventricular ejection fraction (LVEF) measurements obtained after stress and at rest with a same-day perfusion-function imaging protocol. MATERIALS AND METHODS: One hundred twenty-six patients underwent a same-day rest-stress (61%) or stress-rest (39%) protocol and gated single photon emission computed tomography (SPECT). Perfusion analysis was performed with a 12-segment model. Defects were scored (0 = no defect, 1 = mild defect, 2 = moderate defect, and 3 = severe defect); differences between the summed stress and resting scores of greater than three indicated substantial ischemia. RESULTS: Resting and poststress LVEFs correlated significantly (r = 0.97, P <.001); however, patients with and patients without ischemia had significant differences in poststress versus resting LVEFs (-4.0 vs 1.0, respectively; P <.01). In patients with ischemia versus patients without ischemia, subgroup analysis stress-rest (-2.5 vs 1.0, P =.047) and rest-stress (-4.0 vs 1.0, P =.006) protocols yielded similar results. CONCLUSION: In patients with clinically important stress-induced perfusion abnormalities, the LVEF after stress was significantly lower than the LVEF at rest with same-day rest-stress and stress-rest imaging protocols. In the clinical setting, poststress LVEFs may be lower than true resting measurements, particularly in patients with moderate to severe stress-induced ischemia.

Adenosine↗
PubMed2004

Plasma volume restoration with salt tablets and water after bed rest prevents orthostatic hypotension and changes in supine hemodynamic and endocrine variables.

Head-down bed rest changes the values of many cardiovascular and endocrine variables and also elicits significant hypovolemia. Because previous studies had not controlled for hypovolemia, it is unknown whether the reported changes were primary effects of bed rest or secondary effects of bed rest-induced hypovolemia. We hypothesized that restoring plasma volume with salt tablets and water after 12 days of head-down bed rest would result in an absence of hemodynamic and endocrine changes and a reduced incidence of orthostatic hypotension. In 10 men, we measured changes from pre-bed-rest to post-bed-rest in venous and arterial pressures; heart rate; stroke volume; cardiac output; vascular resistance; plasma norepinephrine, epinephrine, vasopressin, renin activity (PRA), and aldosterone responses to different tilt levels (0 degrees, -10 degrees, 20 degrees, 30 degrees, and 70 degrees); and plasma volume and platelet alpha2- and lymphocyte beta2-adrenoreceptor densities and affinities (0 degrees tilt only). Fluid loading at the end of bed rest restored plasma volume and resulted in the absence of post-bed-rest orthostatic hypotension and changes in supine hemodynamic and endocrine variables. Fluid loading did not prevent post-bed-rest increases in beta2-adrenoreceptor density or decreases in the aldosterone-to-PRA ratio (P = 0.05 for each). Heart rate, epinephrine, and PRA responses to upright tilt after bed rest were increased (P < 0.05), despite the fluid load. These results suggest that incidents of orthostatic hypotension and many of the changes in supine hemodynamic and endocrine variables in volume-depleted bed-rested subjects occur secondarily to the hypovolemia. Despite normovolemia after bed rest, beta2-adrenoreceptors were upregulated, and heart rate, epinephrine, and PRA responses to tilt were augmented, indicating that these changes are independent of volume depletion.

Adult↗
PubMed1996

Serum urate and cholesterol levels in endurance trained volunteers during acute and rigorous bed rest conditions.

The objective of this investigation was to determine serum urate and cholesterol concentrations in endurance trained volunteers during exposure to acute (abrupt restriction of muscular activity) and rigorous bed rest conditions of seven days. The studies were performed on 30 long distance runners aged 22-25 who had a peak of VO2 of 65.5 +/- 2.7 ml.kg-1.min-1 on the average prior to their participation in the study. The volunteers were divided into three equal groups: the volunteers in the 1st group were under normal ambulatory conditions (control subjects), the volunteers of the 2nd group subjected to an acute bed rest regime (acute bed rested subjects) and the volunteers of the 3rd group were submitted to a rigorous bed rest regime (rigorous bed rested subjects). All volunteers were on an average of 14.2 km/day before taking part in the study. The 2nd and 3rd groups of volunteers were kept under a rigorous bed rest regime for seven days. During the perbed rest period and during the actual bed rest periods (acute and rigorous bed rest periods) serum cholesterol and uric acid levels were measured. During the 1st day of acute and rigorous bed rest periods serum uric acid and cholesterol concentrations increased significantly (p < or = 0.05), on the 3rd day increased somewhat more and during the 7th day they increased further. These changes were more pronounced during acute than rigorous bed rest conditions. It was concluded that increases in uric acid and cholesterol concentrations in serum appear to reflect more stresses that associated with acute than rigorous bed rest conditions in endurance trained volunteers.

Adult↗
PubMed1997

Regulation of the resting potential of rabbit pulmonary artery myocytes by a low threshold, O2-sensing potassium current.

1. The contributions of specific K+ currents to the resting membrane potential of rabbit isolated, pulmonary artery myocytes, and their modulation by hypoxia, were investigated by use of the whole-cell, patch-clamp technique. 2. In the presence of 10 microM glibenclamide the resting potential (-50 +/- 4 mV, n = 18) was unaffected by 10 microM tetraethylammonium ions, 200 nM charybdotoxin, 200 nM iberiotoxin, 100 microM ouabain or 100 microM digitoxin. The negative potential was therefore maintained without ATP-sensitive (KATP) or large conductance Ca(2+)-sensitive (BKCa) K channels, and without the Na(+)-K+ ATPase. 3. The resting potential, the delayed rectifier current (IK(V)) and the A-like K+ current (IK(A)) were all reduced in a concentration-dependent manner by 4-aminopyridine (4-AP) and by quinine. 4. 4-AP was equally potent at reducing the resting potential and IK(V), 10 mM causing depolarization from -44 mV to -22 mV with accompanying inhibition of IK(V) by 56% and IK(A) by 79%. In marked contrast, the effects of quinine on resting potential were poorly correlated with its effects on both IK(A) and IK(V). At 10 mM, quinine reduced IK(V) and IK(A) by 47% and 38%, respectively, with no change in the resting potential. At 100 microM, both currents were almost abolished while the resting potential was reduced < 50%. Raising the concentration to 1 mM had little further effect on IK(A) or IK(V), but essentially abolished the resting potential. 5. Reduction of the resting potential by quinine was correlated with inhibition of a voltage-gated, low threshold, non-inactivating K+ current, IK(N). Thus, 100 microM quinine reduced both IK(N) and the resting potential by around 50%. 6. The resting membrane potential was the same whether measured after clamping the cell at -80 mV, or immediately after a prolonged period of depolarization at 0 mV, which inactivated IK(A) and IK(V), but not IK(N). 7. When exposed to a hypoxic solution, the O2 tension near the cell fell from 125 +/- 6 to 14 +/- 2 mmHg (n = 20), resulting in a slow depolarization of the myocyte membrane to -35 +/- 3 mV (n = 16). The depolarization occurred without a change in the amplitude of IK(V) or IK(A), but it was accompanied by 60% inhibition of IK(N) at 0 mV. 8. Our findings suggest that the resting potential of rabbit pulmonary artery myocytes depends on IK(N), and that inhibition of IK(N) may mediate the depolarization induced by hypoxia.

Animals↗
PubMed2004

The repressor element silencing transcription factor (REST)-mediated transcriptional repression requires the inhibition of Sp1.

The terminal differentiation of neuronal and pancreatic beta-cells requires the specific expression of genes that are targets of an important transcriptional repressor named RE-1 silencing transcription factor (REST). The molecular mechanism by which these REST target genes are expressed only in neuronal and beta-cells and are repressed by REST in other tissues is a central issue in differentiation program of neuronal and beta-cells. Herein, we showed that the transcriptional factor Sp1 was required for expression of most REST target genes both in insulin-secreting cells and neuronal-like cells where REST is absent. Inhibition of REST in a non-beta and a non-neuronal cell model restored the transcriptional activity of Sp1. This activity was also restored by trichostatin A indicating the requirement of histone deacetylases for the REST-mediated silencing of Sp1. Conversely, exogenous introduction of REST blocked Sp1-mediated transcriptional activity. The REST inhibitory effect was mediated through its C-terminal repressor domain, which could interact with Sp1. Taken together, these data show that the inhibition of Sp1 by REST is required for the silencing of its target genes expression in non-neuronal and in non-beta-cells. We conclude that the interplay between REST and Sp1 determines the cell-specific expression of REST target genes.

Animals↗
PubMed1986

Acute and chronic haemodynamic effects of doxazosin in hypertension at rest and during exercise.

The acute and chronic haemodynamic effects of doxazosin were studied in 14 patients (10 males, four females) with essential hypertension, at rest supine and sitting and during 100 W bicycling exercise. Blood pressure (BP) was recorded intra-arterially in the brachial artery, cardiac output (CO) was measured by Cardiogreen and heart rate (HR) by ECG. One hour after injection of doxazosin 0.5-1.0 mg i.v., mean arterial pressure (MAP) was reduced by 8% at rest supine, 12% at rest sitting and 10% at 100 W (all changes statistically significant), associated with a reduction in total peripheral resistance index (TPRI) of 5% at rest supine, 9% at rest sitting (P less than 0.01) and 14% at 100 W (P less than 0.001). HR was slightly increased (5%, NS) and cardiac index (CI) was unchanged during rest and slightly increased during exercise (4%, P less than 0.05). Patients were then given doxazosin capsules (2-16 mg once daily), aiming at a casual BP of less than or equal to 140/90 mmHg without side-effects. Central haemodynamics were restudied after 1 year. After 1 year of doxazosin treatment, MAP was reduced by 13% at rest supine, 16% at rest sitting and 17% at 100 W (all P-values less than 0.001). TPRI was reduced by 19% at rest supine, 20% at rest sitting and 18% at 100 W (all changes statistically significant). CI was increased by 8% at rest supine (P less than 0.05) but was unchanged sitting and at 100 W. It is concluded that doxazosin lowers BP through a reduction in TPRI acutely as well as chronically, without reductions in CO. BP control was maintained over 1 year without side-effects. Thus, doxazosin normalizes central haemodynamics in patients with mild to moderate essential hypertension, both at rest and during exercise.

Administration, Oral↗
PubMed1997

Effects of [Ca2+]i, SR Ca2+ load, and rest on Ca2+ spark frequency in ventricular myocytes.

In heart, spontaneous local increases in cytosolic Ca2+ concentration ([Ca2+]i) called "Ca2+ sparks" may be fundamental events underlying both excitation-contraction coupling and resting Ca2+ leak from the sarcoplasmic reticulum (SR). In this study, resting Ca2+ sparks were analyzed in rabbit and rat ventricular myocytes with laser scanning confocal microscopy and the fluorescent Ca2+ indicator fluo 3. During the first 20 s of rest after regular electrical stimulation, both the frequency of Ca2+ sparks and SR Ca2+ content gradually decreased in rabbit. When rabbit SR Ca2+ content was decreased by reduction of stimulation rate. the initial resting spark frequency was also decreased, even though resting [Ca2+]i was unchanged. The rest-dependent decrease in spark frequency in rabbit cells was prevented by inhibition of Na+/Ca2+ exchange (which also prevents SR Ca2+ depletion during rest). These results suggest that elevation of SR Ca2+ content can increase Ca2+ spark frequency. In contrast to rabbit cells, 20 s of rest produced a gradual increase in spark frequency in rat cells, although SR Ca2+ content was constant and Ca2+ influx was completely prevented. This indicates that there is a time-dependent increase in spark probability during rest that is independent of [Ca2+]i or SR Ca2+. This effect was also apparent in rabbit cells when SR Ca2+ depletion was prevented by blocking Na+/Ca2+ exchange. Stimulation of Ca2+ extrusion via Na+/Ca2+ exchange in the rat (by Ca2+-free superfusion, which slowly depletes SR Ca2+ content) converted the normal rest-dependent increase in spark frequency to a decrease. The amplitude of individual Ca2+ sparks increased with increasing SR Ca2+ content. In the Ca2+-overloaded state, fusion of sparks or long-lasting localized increases of [Ca2+]i were observed with increased spark frequency. We conclude that the resting frequency of Ca2+ sparks can be independently affected by changes in SR Ca2+ content, [Ca2+]i, or rest period. The latter may reflect recovery of the SR Ca2+ release channels from inactivation or adaptation.

Animals↗
PubMed1990

Impact of energy intake and exercise on resting metabolic rate.

Resting metabolic rate is modulated by the amount of calories consumed in the diet relative to energy expenditure. Excessive consumption of energy appears to increase resting metabolic rate while fasting and very low calorie dieting causes resting metabolic rate to decrease. Since the metabolic rate at rest is the primary component of daily energy expenditure, its reduction with caloric restriction makes it difficult for obese individuals to lose weight and to maintain weight that is lost. Whether exercise has a carry-over effect on resting metabolic rate remains controversial, even though this question has been studied extensively during the last 90 years. Reasons for contradictory results include variations in control of prior diet and exercise patterns, inadequate exercise frequency, intensity and duration, and the possibility of response to exercise varying between individuals. Several lines of evidence suggest exercise may modulate resting metabolic rate. Bed rest in sedentary individuals leads to a reduction in resting metabolic rate. Similarly, in highly trained runners, cessation of daily exercise training lowers resting metabolic rate by about 7 to 10%. Resting metabolic rate is depressed in previously sedentary obese individuals on a very low calorie diet, but it quickly returns to the predieting level when exercise of sufficient frequency, intensity and duration is undertaken while dieting. These findings suggest caloric intake and daily exercise can modulate resting metabolic rate. Exercise of adequate intensity and duration may also enhance resting metabolic rate.

Basal Metabolism↗
PubMed2005

The effects of finger rest positions on hand muscle load and pinch force in simulated dental hygiene work.

One of the techniques taught in dental and dental hygiene programs is to use finger rests to stabilize the instrument while performing dental scaling or other types of dental work. It is believed that finger rests may also reduce muscle stress and prevent injury due to muscle fatigue. In this study the effects of three different finger rest positions on hand muscle activity and thumb pinch force were compared. Twelve predental students performed simulated dental scaling tasks on a manikin using three different finger rest positions: 1) no finger rest, 2) one finger rest, and 3) two finger rests. Muscle activity and thumb pinch force were measured by surface electromyography and a pressure sensor, respectively. Using two finger rests was always associated with reduced thumb pinch force and muscle activity, as compared to not using any finger rests (p<0.05), while using one finger rest reduced thumb pinch force and muscle activity in most cases. Hence, using finger rests plays an important role in reducing the muscle load of the hand in students performing simulated dental hygiene work. It is concluded that dental and dental hygiene students may benefit from instructions for using finger rests at an early stage of their clinical training. Including biomechanical and ergonomic principles in dental and dental hygiene curricula will raise awareness of ergonomics among dental practitioners and help them incorporate these principles into daily practice.

Adult↗
PubMedDate not supplied

The effects of acetylcholine and catecholamines on post-rest phenomena in rabbit and guinea-pig atria and on accompanying shifts of 45Ca in guinea-pig atrial muscle.

We studied the pattern of post-rest activation and shifts of 45Ca in the isolated mammalian atrial muscle. The first contraction evoked in the rabbit and guinea-pig atrial muscle after 10 min rest was several times stronger than the steady-state beats at a rate of 60/min. Contractile force (CF) declined to 20-50% of control during the next 1-3 beats and recovered to the pre-rest level upon subsequent stimulation. The post-rest beats were negligibly affected by noradrenaline (NA), isoproterenol (IS) acetylcholine (ACh), carbachol (CCh) and Ni, whereas the steady-state beats were readily affected by all these drugs or ions. Post-rest potentiation was completely inhibited by caffeine in a concentration of 10 mM. The guinea-pig atria, equilibrated for 60 min in 45Ca containing solution and stimulated at a rate of 60/min, contained 4.47 +/- 0.16 mmol 45Ca/kg wet weight (w.w.). Ten min of rest resulted in a drop of this content to 3.52 +/- 0.13 mmol/kg w.w. despite the continued presence of 45Ca in the superfusing solution. Three initial post-rest beats resulted in further drop of the content of 45Ca to 2.62 +/- 0.14 mmol/kg w.w. Continued post-rest stimulation resulted in a recovery of the pre-rest 45Ca content. This recovery was inhibited by ACh and CCh. Both drugs inhibited 45Ca loss during the initial 3 beats. Neither this loss nor recovery were affected by IS. It is concluded that calcium (Ca) fraction described in the previous papers [11, 15] as Ca2 in the guinea-pig ventricular muscle plays an important role in the force-frequency relations also in the atrial muscle. However, unlike in ventricular muscle only about half of it is released from the cells upon rest whereas the remaining Ca is taken up by the release compartment and used to activate the strong post-rest contraction. It is thereafter extruded from the cells which results in severe depletion of intracellular Ca stores. Fraction Ca2 is re-accumulated during the post-rest stimulation resulting in recovery of the contractile force.

Acetylcholine↗
PubMed2004

Bed rest for acute low-back pain and sciatica.

BACKGROUND: Low-back pain (LBP) is a common reason for consulting a general practitioner, and advice on daily activities is an important part of the primary care management of low-back pain. OBJECTIVES: To assess the effects of advice to rest in bed for patients with acute LBP or sciatica. SEARCH STRATEGY: We searched the Cochrane Back Group Specialized Registry, CENTRAL, MEDLINE, EMBASE, Sport, and SCISEARCH to March 2003, reference lists of relevant articles, and contacted authors of relevant articles. SELECTION CRITERIA: Randomised or controlled clinical trials with quasi-randomisation (alternate allocation, case record numbers, dates of birth, etc.), in any language, where the effectiveness of advice to rest in bed was evaluated. The main outcomes of interest were pain, functional status, recovery and return to work. DATA COLLECTION AND ANALYSIS: Two reviewers independently selected trials for inclusion, assessed the internal validity of included trials and extracted data. Investigators were contacted to obtain missing information. MAIN RESULTS: Eleven trials (1963 patients) were included in this updated version. There is high quality evidence that people with acute LBP who are advised to rest in bed have a little more pain [Standardised Mean Difference (SMD) 0.22 (95% Confidence Interval (CI): 0.02, 0.41)] and a little less functional recovery [SMD 0.29 (95% CI: 0.05, 0.45)] than those advised to stay active. For patients with sciatica, there is moderate quality evidence of little or no difference in pain [SMD -0.03 (95% CI: -0.24, 0.18)] or functional status [SMD 0.19 (95% CI: -0.02, 0.41)] between bed rest and staying active. For patients with acute LBP, there is moderate quality evidence of little or no difference in pain intensity or functional status between bed rest and exercises. For patients with sciatica, there is moderate quality evidence of little or no difference in pain intensity between bed rest and physiotherapy, but small improvements in functional status [Weighted Mean Difference 6.9 (on a 0-100 scale) (95% CI: 1.09, 12.74)] with physiotherapy. There is moderate quality evidence of little or no difference in pain intensity or functional status between two to three days and seven days of bed rest. REVIEWERS' CONCLUSIONS: For people with acute LBP, advice to rest in bed is less effective than advice to stay active. For patients with sciatica, there is little or no difference between advice to rest in bed and advice to stay active. There is little or no difference in the effect of bed rest compared to exercises or physiotherapy, or seven days of bed rest compared with two to three.

Acute Disease↗
PubMed2005

Bed rest with or without hospitalisation for hypertension during pregnancy.

BACKGROUND: Bed rest or restriction of activity, with or without hospitalisation, have been advocated for women with hypertension during pregnancy to improve pregnancy outcome. However, benefits need to be demonstrated before such interventions can be recommended since restricted activity may be disruptive to women's lives, expensive, and increase the risk of thromboembolism. OBJECTIVES: To assess the effects on the mother and the baby of different degrees of bed rest, compared with each other, and with routine activity, in hospital or at home, for primary treatment of hypertension during pregnancy. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (April 2005), the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 1, 2005), and EMBASE (January 2002 to December 2004). SELECTION CRITERIA: Randomised trials evaluating bed rest for women with hypertension in pregnancy were selected. DATA COLLECTION AND ANALYSIS: Two review authors assessed trials for inclusion independently, and extracted data. Data were entered into RevMan software and double-checked. MAIN RESULTS: Four small trials (449 women) were included. Three were of good quality. Two trials (145 women) compared strict bed rest with some rest, in hospital, for women with proteinuric hypertension. There was insufficient evidence to demonstrate any differences between the groups for reported outcomes. Two trials (304 women) compared some bed rest in hospital with routine activity at home for non-proteinuric hypertension. There was reduced risk of severe hypertension (1 trial, 218 women; RR 0.58, 95% CI 0.38 to 0.89) and a borderline reduction in risk of preterm birth (1 trial, 218 women; RR 0.53, CI 0.29 to 0.99) with some rest compared to normal activity. More women in the bed rest group opted not to have the same management in future pregnancies, if the choice were given (1 trial, 86 women; RR 3.00, 95% CI 1.43 to 6.31). There were no significant differences for any other outcomes. AUTHORS' CONCLUSIONS: Few randomised trials have evaluated rest for women with hypertension during pregnancy, and important information on side-effects and cost implication is missing from available trials. Although one small trial suggests that some bed rest may be associated with reduced risk of severe hypertension and preterm birth, these findings need to be confirmed in larger trials. At present, there is insufficient evidence to provide clear guidance for clinical practice. Therefore, bed rest should not be recommended routinely for hypertension in pregnancy, especially since more women appear to prefer unrestricted activity, if the choice were given.

Bed Rest↗
PubMed2005

Bed rest during pregnancy for preventing miscarriage.

BACKGROUND: Miscarriage is pregnancy loss before 23 weeks of gestational age and it happens in 10% to 15% of pregnancies depending on maternal age and parity. It is associated with chromosomal defects in about a half or two thirds of cases. Many interventions have been used to prevent miscarriage but bed rest is probably the most commonly prescribed especially in cases of threatened miscarriage and history of previous miscarriage. Since the etiology of miscarriage in most of the cases is not related to an excess of activity, it is unlikely that bed rest could be an effective strategy to reduce spontaneous miscarriage. OBJECTIVES: To evaluate the effect of prescription of bed rest during pregnancy to prevent miscarriage in women at high risk of miscarriage. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group trials register (July 2004). In addition, we searched The Cochrane Central Register of Controlled Trials (The Cochrane Library), MEDLINE, POPLINE, LILACS and EMBASE. SELECTION CRITERIA: We included all published, unpublished and ongoing randomized trials with reported data which compare clinical outcomes in pregnant women who were prescribed bed rest in hospital or at home for preventing miscarriage compared with alternative care or no intervention. DATA COLLECTION AND ANALYSIS: Two authors independently assessed the methodological quality of included trials using the methods described in the Cochrane Reviewers' Handbook. Studies were included irrespective of their methodological quality. MAIN RESULTS: Only two studies including 84 women were identified. There was no statistically significant difference in the risk of miscarriage in the bed rest group versus the no bed rest group (placebo or other treatment) (relative risk (RR) 1.54, 95% confidence interval (CI) 0.92 to 2.58). Neither bed rest in hospital nor bed rest at home showed a significant difference in the prevention of miscarriage. There was a higher risk of miscarriage in those women in the bed rest group than in those in the human chorionic gonadotrophin therapy group with no bed rest (RR 2.50, 95% CI 1.22 to 5.11). It seems that the small number of participants included in these studies is a main factor to make this analysis inconclusive. AUTHORS' CONCLUSIONS: There is insufficient evidence of high quality that supports a policy of bed rest in order to prevent miscarriage in women with confirmed fetal viability and vaginal bleeding in first half of pregnancy.

Abortion, Spontaneous↗
PubMed1996

Diurnal rhythms of plasma renin activity, atrial natriuretic peptide and arterial pressure during head-down bed rest in humans.

The effects of prolonged head-down bed rest on the rhythms of several parameters (blood pressure, heart rate, haematocrit, plasma renin activity (PRA), atrial natriuretic peptide (ANP) were assessed in six healthy men, aged 33 (SEM 2) years, who were submitted to bed rest for 28 days (D1-28). Systolic and diastolic blood pressure (BPs and BPd) and heart rate were measured at 0700 and 1900 hours; circulating PRA and ANP were determined from blood samples drawn at 0800, 1000, 1200, 1500, 1800 and 2200 hours before bed rest (D - 5), D1, 2, 7, 20, 27 during bed rest and post bed rest (D + 2). The BPs was the lowest at 0700 hours and increased at 1900 hours. There was a significant difference between values during all the measurements. The BPd and heart rate were lower at 0700 hours before and after bed rest and no significant difference appeared between these two values during the bed rest. The PRA and ANP concentrations were more stable during bed rest, and had not returned to original rhythmicity 2 days after bed rest. The mean daily concentration of ANP decreased during bed rest. It would seem from this study that changes occur in those rhythms during bed rest.

Adult↗
PubMed2000

Changes in the elastic properties of tendon structures following 20 days bed-rest in humans.

The purpose of this study was to investigate the effects of 20 days bed-rest on the elastic properties of tendon structures of the human knee extensor muscles in vivo. Six healthy men carried out a 6 degrees head-down bed-rest for 20 days. Muscle volume and maximal voluntary contraction (MVC) torque of the quadriceps femoris muscle significantly decreased by an average of 7.8 (SD 2.7)% and 14.9 (SD 6.9)%, respectively. Before and after bed-rest, the elongation (l) of the tendon and aponeurosis of vastus lateralis muscle was measured directly by ultrasonography, while the subjects performed ramp isometric knee extension up to MVC. The extent of l tended to be greater after bed-rest. The l above 110 N was significantly greater after bed-rest. Furthermore, the mean stiffness after bed-rest [35.5 (SD 7.8) N x mm(-1)] was significantly lower than that before bed-rest [52.6 (SD 19.2) N x mm(-1)]. The rate of torque development significantly reduced after bed-rest by an average of 47%, and the bed-rest induced a lengthening in the electromechanical delay (mean 21%). These results suggest that bed-rest results in a decrease in the stiffness of tendon structures with a reduction of muscle strength and volume. These adaptations of the tendon structures to bed-rest would bring about the changes in electromechanical delay and rate of torque development.

Adult↗
PubMed1990

Technetium-99m sestamibi myocardial imaging: same-day rest-stress studies and dipyridamole.

Unlike thallium-201, technetium-99m (Tc-99m) sestamibi does not redistribute in the myocardium after injection. Thus, 2 separate injections, 1 at rest and the other at stress (or after dipyridamole), are required to differentiate ischemia from scar. From a physical viewpoint, a 24-hour interval between the 2 injections is preferable for detection of coronary artery disease (CAD) with Tc-99m sestamibi imaging. However, same-day studies are more convenient in clinical practice. Results of studies using different Tc-99m sestamibi injection protocols are presented with emphasis on the advantages of a rest-stress injection sequence with a low dose at rest (7 mCi) followed 2 hours later by a higher dose at stress (25 mCi). A prospective study was conducted in a patient population with proven CAD using same-day studies to compare a rest-stress (7 and 25 mCi, respectively) to a stress-rest (7 and 25 mCi) Tc-99m sestamibi injection sequence. There was an agreement in 87.3% of the analyzed segments between the 2 protocols. However, the largest discordance for type of defect applied to 7.4% of the segments judged ischemic in the rest-stress protocol, which were called scars on stress-rest. This study showed that a rest-stress sequence is preferable when using a same-day protocol with a short time interval (less than 2 hours) between the 2 Tc-99m sestamibi injections because the rest image performed initially represents a "true" rest study, which is not necessarily the case with the stress-rest sequence. Preliminary studies were performed to evaluate dipyridamole with Tc-99m sestamibi imaging in normal subjects and in patients with CAD. These studies showed that treadmill and dipyridamole Tc-99m sestamibi imaging are comparable and the results are similar to those obtained with thallium-201.

Coronary Disease↗
PubMed2004

Sedative music reduces anxiety and pain during chair rest after open-heart surgery.

Open-heart surgery patients report anxiety and pain with chair rest despite opioid analgesic use. The effectiveness of non-pharmacological complementary methods (sedative music and scheduled rest) in reducing anxiety and pain during chair rest was tested using a three-group pretest-posttest experimental design with 61 adult postoperative open-heart surgery patients. Patients were randomly assigned to receive 30 min of sedative music (N=19), scheduled rest (N=21), or treatment as usual (N=21) during chair rest. Anxiety, pain sensation, and pain distress were measured with visual analogue scales at chair rest initiation and 30 min later. Repeated measures MANOVA indicated significant group differences in anxiety, pain sensation, and pain distress from pretest to posttest, P<0.001. Univariate repeated measures ANOVA (P< or =0.001) and post hoc dependent t-tests indicated that in the sedative music and scheduled rest groups, anxiety, pain sensation, and pain distress all decreased significantly, P<0.001-0.015; while in the treatment as usual group, no significant differences occurred. Further, independent t-tests indicated significantly less posttest anxiety, pain sensation, and pain distress in the sedative music group than in the scheduled rest or treatment as usual groups (P<0.001-0.006). Thus, in this randomized control trial, sedative music was more effective than scheduled rest and treatment as usual in decreasing anxiety and pain in open-heart surgery patients during first time chair rest. Patients should be encouraged to use sedative music as an adjuvant to medication during chair rest.

Aged↗