1
|
Cunningham C, Tapking C, Salter M, Seeton R, Kramer GC, Prough DS, Sheffield-Moore M, Kinsky MP. The physiologic responses to a fluid bolus administration in old and young healthy adults. Perioper Med (Lond) 2022; 11:30. [PMID: 35971161 PMCID: PMC9380305 DOI: 10.1186/s13741-022-00266-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 04/15/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Organ function is known to decline with age. Optimizing cardiac, pulmonary and renal function in older adults has led to significant improvements in perioperative care. However, when substantial blood loss and fluid shifts occur, perioperative outcomes still remains poor, especially in older adults. We suspect that this could be due to age-related changes in endothelial function-an organ controlling the transport of fluid and solutes. The capillary filtration coefficient (CFC) is an important determinant of fluid transport. The CFC can be measured in vivo, which provides a tool to estimate endothelial barrier function. We have previously shown that the CFC increases when giving a fluid bolus resulting in increased vascular and extravascular volume expansion, in young adults. This study aimed to compare the physiologic determinants of fluid distribution in young versus older adults so that clinicians can best optimize perioperative fluid therapy. METHODS Ten healthy young volunteers (ages 21-35) and nine healthy older volunteers (ages 60-75) received a 10 mL/kg fluid bolus over the course of twenty minutes. Hemodynamics, systolic and diastolic heart function, fluid volumetrics and microcirculatory determinants were measured before, during, and after the fluid bolus. RESULTS Diastolic function was reduced in older versus younger adults before and after fluid bolus (P < 0.01). Basal CFC and plasma oncotic pressure were lower in the older versus younger adults. Further, CFC did not increase in older adults following the fluid bolus, whereas it did in younger adults (p < 0.05). Cumulative urinary output, while lower in older adults, was not significantly different (p = 0.059). Mean arterial pressure and systemic vascular resistance were elevated in the older versus younger adults (p < 0.05). CONCLUSION Older adults show a less reactive CFC to a fluid bolus, which could reduce blood to tissue transport of fluid. Diastolic dysfunction likely contributes to fluid maldistribution in older adults.
Collapse
Affiliation(s)
- Cordell Cunningham
- Department of Anesthesiology, The University of Texas Medical Branch, Galveston, TX, USA
| | - Christian Tapking
- Department of Surgery, The University of Texas Medical Branch, Galveston, TX, USA
- Department of Hand, Plastic and Reconstructive Surgery, Microsurgery, Burn Trauma Center, BG Unfallklinik Ludwigshafen, University of Heidelberg, Heidelberg, Germany
| | - Michael Salter
- Department of Anesthesiology, The University of Texas Medical Branch, Galveston, TX, USA
| | - Roger Seeton
- Department of Anesthesiology, The University of Texas Medical Branch, Galveston, TX, USA
| | - George C Kramer
- Department of Anesthesiology, The University of Texas Medical Branch, Galveston, TX, USA
| | - Donald S Prough
- Department of Anesthesiology, The University of Texas Medical Branch, Galveston, TX, USA
| | | | - Michael P Kinsky
- Department of Anesthesiology, The University of Texas Medical Branch, Galveston, TX, USA.
| |
Collapse
|
2
|
Assessment of Upper Extremity Venous Compliance in Patients With Abdominal Aortic Aneurysms. Eur J Vasc Endovasc Surg 2020; 60:739-746. [PMID: 32778487 DOI: 10.1016/j.ejvs.2020.07.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 06/28/2020] [Accepted: 07/03/2020] [Indexed: 11/21/2022]
Abstract
OBJECTIVE Abdominal aortic aneurysm (AAA) is associated with morphological and functional changes in both aneurysmal and non-aneurysmal arteries. However, it remains uncertain whether similar changes also exist in the venous vasculature. The aim of this study was to evaluate global venous function in patients with AAA and controls. METHODS This experimental study comprised 31 men with AAA (mean ± standard deviation age 70.0 ± 2.8 years) and 29 male controls (aged 70.6 ± 3.4 years). Venous occlusion plethysmography (VOP) was used to evaluate arm venous compliance at venous pressures between 10 and 60 mmHg in steps of 5 mmHg. Compensatory mobilisation of venous capacitance blood (capacitance response) was measured with a volumetric technique during experimental hypovolaemia induced by lower body negative pressure (LBNP). RESULTS The VOP induced pressure-volume curve was significantly less steep in patients with AAA (interaction, p < .001), indicating lower venous compliance. Accordingly, the corresponding pressure-compliance curves displayed reduced venous compliance at lower venous pressures in patients with AAA vs. controls (interaction, p < .001; AAA vs. control, p = .018). After adjusting for arterial hypertension, diabetes mellitus, hyperlipidaemia, chronic obstructive pulmonary disease, and smoking, VOP detected differences in venous compliance remained significant at low venous pressures, that is, at 10 mmHg (p = .008), 15 mmHg (p = .013), and 20 mmHg (p = .026). Mean venous compliance was negatively correlated with aortic diameter (r = -.332, p = .010). Mobilisation of venous capacitance response during LBNP was reduced by approximately 25% in patients with AAA (p = .030), and the redistribution of venous blood during LBNP was negatively correlated with aortic diameter (r = -.417, p = .007). CONCLUSION Men with AAA demonstrated reduced venous compliance and, as a result, a lesser capacity to mobilise peripheral venous blood to the central circulation during hypovolaemic stress. These findings imply that the AAA disease may be accompanied by functional changes in the venous vascular wall.
Collapse
|
3
|
Skoog J, Nelzén O, Zachrisson H. Venous Compliance in Great Saphenous Vein Incompetence: Pre- and Post-interventional Changes. EJVES Vasc Forum 2020. [PMCID: PMC7320196 DOI: 10.1016/j.ejvssr.2019.11.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Objective Methods Results Conclusions Venous compliance reflects the mechanical properties of the vessel wall. Calf venous compliance is reduced in patients with great saphenous vein insufficiency. Venous reflux parameters markedly improve after surgical intervention. Venous compliance is further reduced in the post-operative state.
Collapse
Affiliation(s)
- Johan Skoog
- Department of Clinical Physiology and Department of Health, Medicine and Caring Sciences, Linköping University, Linköping, Sweden
- Corresponding author. Department of Clinical Physiology and Department of Health, Medicine and Caring Sciences, Linköping University, SE 581 85, Linköping, Sweden.
| | - Oskar Nelzén
- Department of Thoracic and Vascular Surgery and Department of Health, Medicine and Caring Sciences, Linköping University, Linköping, Sweden
| | - Helene Zachrisson
- Department of Clinical Physiology and Department of Health, Medicine and Caring Sciences, Linköping University, Linköping, Sweden
| |
Collapse
|
4
|
Fulop GA, Tarantini S, Yabluchanskiy A, Molnar A, Prodan CI, Kiss T, Csipo T, Lipecz A, Balasubramanian P, Farkas E, Toth P, Sorond F, Csiszar A, Ungvari Z. Role of age-related alterations of the cerebral venous circulation in the pathogenesis of vascular cognitive impairment. Am J Physiol Heart Circ Physiol 2019; 316:H1124-H1140. [PMID: 30848677 PMCID: PMC6580383 DOI: 10.1152/ajpheart.00776.2018] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 01/31/2019] [Accepted: 02/18/2019] [Indexed: 02/07/2023]
Abstract
There has been an increasing appreciation of the role of vascular contributions to cognitive impairment and dementia (VCID) associated with old age. Strong preclinical and translational evidence links age-related dysfunction and structural alterations of the cerebral arteries, arterioles, and capillaries to the pathogenesis of many types of dementia in the elderly, including Alzheimer's disease. The low-pressure, low-velocity, and large-volume venous circulation of the brain also plays critical roles in the maintenance of homeostasis in the central nervous system. Despite its physiological importance, the role of age-related alterations of the brain venous circulation in the pathogenesis of vascular cognitive impairment and dementia is much less understood. This overview discusses the role of cerebral veins in the pathogenesis of VCID. Pathophysiological consequences of age-related dysregulation of the cerebral venous circulation are explored, including blood-brain barrier disruption, neuroinflammation, exacerbation of neurodegeneration, development of cerebral microhemorrhages of venous origin, altered production of cerebrospinal fluid, impaired function of the glymphatics system, dysregulation of cerebral blood flow, and ischemic neuronal dysfunction and damage. Understanding the age-related functional and phenotypic alterations of the cerebral venous circulation is critical for developing new preventive, diagnostic, and therapeutic approaches to preserve brain health in older individuals.
Collapse
Affiliation(s)
- Gabor A Fulop
- Vascular Cognitive Impairment and Neurodegeneration Program, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center , Oklahoma City, Oklahoma
- Translational Geroscience Laboratory, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center , Oklahoma City, Oklahoma
- Heart and Vascular Center, Semmelweis University , Budapest , Hungary
| | - Stefano Tarantini
- Vascular Cognitive Impairment and Neurodegeneration Program, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center , Oklahoma City, Oklahoma
- Translational Geroscience Laboratory, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center , Oklahoma City, Oklahoma
| | - Andriy Yabluchanskiy
- Vascular Cognitive Impairment and Neurodegeneration Program, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center , Oklahoma City, Oklahoma
- Translational Geroscience Laboratory, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center , Oklahoma City, Oklahoma
| | - Andrea Molnar
- Heart and Vascular Center, Semmelweis University , Budapest , Hungary
| | - Calin I Prodan
- Veterans Affairs Medical Center , Oklahoma City, Oklahoma
- Department of Neurology, University of Oklahoma Health Sciences Center , Oklahoma City, Oklahoma
| | - Tamas Kiss
- Vascular Cognitive Impairment and Neurodegeneration Program, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center , Oklahoma City, Oklahoma
- Translational Geroscience Laboratory, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center , Oklahoma City, Oklahoma
- Vascular Cognitive Impairment Program, Department of Medical Physics and Informatics, University of Szeged , Szeged , Hungary
| | - Tamas Csipo
- Vascular Cognitive Impairment and Neurodegeneration Program, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center , Oklahoma City, Oklahoma
- Translational Geroscience Laboratory, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center , Oklahoma City, Oklahoma
| | - Agnes Lipecz
- Vascular Cognitive Impairment and Neurodegeneration Program, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center , Oklahoma City, Oklahoma
- Translational Geroscience Laboratory, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center , Oklahoma City, Oklahoma
| | - Priya Balasubramanian
- Vascular Cognitive Impairment and Neurodegeneration Program, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center , Oklahoma City, Oklahoma
- Translational Geroscience Laboratory, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center , Oklahoma City, Oklahoma
| | - Eszter Farkas
- Vascular Cognitive Impairment Program, Department of Medical Physics and Informatics, University of Szeged , Szeged , Hungary
| | - Peter Toth
- Vascular Cognitive Impairment and Neurodegeneration Program, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center , Oklahoma City, Oklahoma
- Translational Geroscience Laboratory, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center , Oklahoma City, Oklahoma
- Cerebrovascular Laboratory, Department of Neurosurgery and Szentagothai Research Center, University of Pecs Medical School , Pecs , Hungary
| | - Farzaneh Sorond
- Department of Neurology, Northwestern University , Chicago, Illinois
| | - Anna Csiszar
- Vascular Cognitive Impairment and Neurodegeneration Program, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center , Oklahoma City, Oklahoma
- Translational Geroscience Laboratory, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center , Oklahoma City, Oklahoma
- Vascular Cognitive Impairment Program, Department of Medical Physics and Informatics, University of Szeged , Szeged , Hungary
| | - Zoltan Ungvari
- Vascular Cognitive Impairment and Neurodegeneration Program, Reynolds Oklahoma Center on Aging, University of Oklahoma Health Sciences Center , Oklahoma City, Oklahoma
- Translational Geroscience Laboratory, Department of Geriatric Medicine, University of Oklahoma Health Sciences Center , Oklahoma City, Oklahoma
- Vascular Cognitive Impairment Program, Department of Medical Physics and Informatics, University of Szeged , Szeged , Hungary
- Semmelweis University, Department of Pulmonology , Budapest , Hungary
| |
Collapse
|
5
|
Skoog J, Zachrisson H, Länne T, Lindenberger M. Reduced compensatory responses to maintain central blood volume during hypovolemic stress in women with vasovagal syncope. Am J Physiol Regul Integr Comp Physiol 2016; 312:R55-R61. [PMID: 27654398 DOI: 10.1152/ajpregu.00166.2016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 08/29/2016] [Accepted: 09/15/2016] [Indexed: 12/14/2022]
Abstract
Although vasovagal syncope (VVS) is a common clinical condition, the underlying pathophysiology is not fully understood. A decrease in cardiac output has recently been suggested as a factor in orthostatic VVS. The aim was to investigate compensatory mechanisms to maintain central blood volume and venous return during hypovolemic stress in women with VVS. Fourteen VVS women (25.7 ± 5.0 yr) and 15 matched controls (22.8 ± 3.2 yr) were investigated. Single-step and graded lower body negative pressure (LBNP) to presyncope were used to create hypovolemic stress. Peripheral mobilization of venous blood from the arm (capacitance response and net capillary fluid absorption) and lower limb blood pooling (calf capacitance response) were evaluated using a volumetric technique. Cardiovascular responses and plasma norepinephrine (P-NE) were measured. Resting P-NE was elevated in VVS women (P < 0.01). Despite a similar hypovolemic stimulus, the increase in P-NE was blunted (P < 0.01) and the maximal percent increase in total peripheral resistance was reduced (P < 0.05) during graded LBNP in VVS women. The arm capacitance response was slower (P < 0.05) and reduced in VVS women at higher levels of LBNP (P < 0.05). Capillary fluid absorption from extra- to intravascular space was reduced by ∼40% in VVS women (P < 0.05). Accordingly, the reduction in cardiac output was more pronounced (P < 0.05). In conclusion, in VVS women, mobilization of peripheral venous blood and net fluid absorption from tissue to blood during hypovolemic stress were decreased partly as a result of an attenuated vasoconstrictor response. This may seriously impede maintenance of cardiac output during hypovolemic stress and could contribute to the pathogenesis of VVS.
Collapse
Affiliation(s)
- Johan Skoog
- Department of Medical and Health Sciences, Linköping University, Linköping, Sweden;
| | - Helene Zachrisson
- Department of Medical and Health Sciences, Linköping University, Linköping, Sweden.,Department of Clinical Physiology, Linköping University, Linköping, Sweden
| | - Toste Länne
- Department of Medical and Health Sciences, Linköping University, Linköping, Sweden.,Department of Thoracic and Vascular Surgery, Linköping University, Linköping, Sweden; and
| | - Marcus Lindenberger
- Department of Medical and Health Sciences, Linköping University, Linköping, Sweden.,Department of Cardiology, Linköping University, Linköping, Sweden
| |
Collapse
|
6
|
Lindenberger M. Reduced Venous Compliance in Young Women with Type 1 Diabetes - Further Aggravated by Prolonged Elevated Levels of HbA1c. Front Endocrinol (Lausanne) 2016; 7:126. [PMID: 27708615 PMCID: PMC5030328 DOI: 10.3389/fendo.2016.00126] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 08/30/2016] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Young patients with diabetes present with reduced compensatory responses to hypovolemic stress. Less compliant veins could be a contributing factor, since roughly two-thirds of the blood volume resides in the venous system as a blood reservoir, adjusting proper venous inflow to the heart. The aim of this study was to measure venous compliance and lower limb blood pooling during hypovolemic stress, and to correlate them to indices of diabetes severity and glucose control. METHODS Fifteen young women with type 1 diabetes (DW) and 18 healthy age-matched women (C) were subjected to lower body negative pressure (LBNP) (11-44 mmHg), creating hypovolemic stress. Lower limb blood pooling was measured with strain gage technique and venous compliance calculated as the relationship between ∆V/∆P. RESULTS DW presented with reduced blood pooling (e.g., blood pooling during LBNP of 44 mmHg, DW, 1.69 ± 0.10; C, 2.10 ± 0.08 (ml/100 ml), and P = 0.003). Calculated venous compliance was also reduced in DW (e.g., compliance at 20 mmHg, DW, 0.046 ± 0.003; C, 0.059 ± 0.002 (ml/100 ml/mmHg), and P = 0.002). A progressive reduction in both venous compliance (P < 0.007) and blood pooling (P < 0.005) was seen with increasing level of HbA1c, and furthermore, less strongly associated with presence of microvascular disease (signs of retinopathy). CONCLUSION Women with type 1 diabetes present with both reduced venous compliance and blood pooling. The reductions were particularly present in patients with long-standing poor glycemic control.
Collapse
Affiliation(s)
- Marcus Lindenberger
- Department of Cardiology and Department of Medical and Health Sciences, Linköping University, Linköping, Sweden
- *Correspondence: Marcus Lindenberger,
| |
Collapse
|
7
|
Lindenberger M, Länne T. Slower lower limb blood pooling in young women with orthostatic intolerance. Exp Physiol 2015; 100:2-11. [PMID: 25557726 DOI: 10.1113/expphysiol.2014.082867] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Accepted: 10/20/2014] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? Orthostatic stress is mostly caused by venous blood pooling in the lower limbs. Venous distension elicits sympathetic responses, and increased distension speed enhances the cardiovascular response. We examine whether lower limb blood pooling rate during lower body negative pressure is linked to orthostatic intolerance. What is the main finding and its importance? A similar amount of blood was pooled in the lower limb, but at a slower rate in women who developed signs of orthostatic intolerance. The difference in blood pooling rate increased with orthostatic stress and was most prominent at a presyncope-inducing level of lower body negative pressure. The findings have implications for the pathophysiology as well as treatment of orthostatic intolerance. Vasovagal syncope is common in young women, but its aetiology remains elusive. Orthostatic stress-induced lower limb blood pooling is linked with central hypovolaemia and baroreceptor unloading. Venous distension in the arm elicits a sympathetic response, which is enhanced with more rapid distension. Our aim was to study both the amount and the speed of lower limb pooling during orthostatic stress and its effects on compensatory mechanisms to maintain cardiovascular homeostasis in women with orthostatic intolerance. Twenty-seven healthy women, aged 20-27 years, were subjected to a lower body negative pressure (LBNP) of 11-44 mmHg. Five women developed symptoms of vasovagal syncope (orthostatic intolerant) and were compared with the remaining women, who tolerated LBNP well (orthostatic tolerant). Lower limb blood pooling, blood flow and compensatory mobilization of venous capacitance blood were measured. Lower body negative pressure induced equal lower limb blood pooling in both groups, but at a slower rate in orthostatic intolerant women (e.g. time to 50% of total blood pooling, orthostatic intolerant 44 ± 7 s and orthostatic tolerant 26 ± 2 s; P < 0.001). At presyncope-inducing LBNP, the mobilization of venous capacitance blood was both reduced (P < 0.05) and much slower in orthostatic intolerant women (P = 0.0007). Orthostatic intolerant women elicited blunted arterial vasoconstriction at low-grade LBNP, activating only cardiopulmonary baroreceptors, while orthostatic tolerant women responded with apparent vasoconstriction (P < 0.0001). In conclusion, slower lower limb blood pooling could contribute to orthostatic intolerance in women. Mobilization of venous capacitance blood from the peripheral to the central circulation was both slower and decreased; furthermore, reduced cardiopulmonary baroreceptor sensitivity was found in women who developed orthostatic intolerance. Further studies including women who experience syncope in daily life are needed.
Collapse
Affiliation(s)
- Marcus Lindenberger
- Department of Medical and Health Sciences, Linköping University, Linköping, Sweden; Department of Cardiology, County Council of Östergötland, Linköping, Sweden
| | | |
Collapse
|
8
|
Skoog J, Zachrisson H, Lindenberger M, Ekman M, Ewerman L, Länne T. Calf venous compliance measured by venous occlusion plethysmography: methodological aspects. Eur J Appl Physiol 2014; 115:245-56. [PMID: 25272971 DOI: 10.1007/s00421-014-3009-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 09/19/2014] [Indexed: 10/24/2022]
Abstract
PURPOSE Calf venous compliance (C calf) is commonly evaluated with venous occlusion plethysmography (VOP) during a standard cuff deflation protocol. However, the technique relies on two not previously validated assumptions concerning thigh cuff pressure (P cuff) transmission and the impact of net fluid filtration (F filt) on C calf. The aim was to validate VOP in the lower limb and to develop a model to correct for F filt during VOP. METHODS Strain-gauge technique was used to study calf volume changes in 15 women and 10 age-matched men. A thigh cuff was inflated to 60 mmHg for 4 and 8 min with a subsequent decrease of 1 mmHg s(-1). Intravenous pressure (P iv) was measured simultaneously. C calf was determined with the commonly used equation [Compliance = β 1 + 2β 2 × P cuff] describing the pressure-compliance relationship. A model was developed to identify and correct for F filt. RESULTS Transmission of P cuff to P iv was 100 %. The decrease in P cuff correlated well with P iv reduction (r = 0.99, P < 0.001). Overall, our model showed that C calf was underestimated when F filt was not accounted for (all P < 0.01). F filt was higher in women (P < 0.01) and showed a more pronounced effect on C calf compared to men (P < 0.05). The impact of F filt was similar during 4- and 8-min VOP. CONCLUSIONS P cuff is an adequate substitute for P iv in the lower limb. F filt is associated with an underestimation of C calf and differences in the effect of F filt during VOP can be accounted for with the correction model. Thus, our model seems to be a valuable tool in future studies of venous wall function.
Collapse
Affiliation(s)
- Johan Skoog
- Department of Medical and Health Sciences, Linköping University, 581 85, Linköping, Sweden,
| | | | | | | | | | | |
Collapse
|
9
|
Lindenberger M, Lindström T, Länne T. Decreased circulatory response to hypovolemic stress in young women with type 1 diabetes. Diabetes Care 2013; 36:4076-82. [PMID: 24130342 PMCID: PMC3836157 DOI: 10.2337/dc13-0468] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE Diabetes is associated with hemodynamic instability during different situations involving acute circulatory stress in daily life. Young men with type 1 diabetes have been shown to have impaired circulatory response to hypovolemic stress. The effect of type 1 diabetes on cardiovascular response to hypovolemia in young women is unknown, however. RESEARCH DESIGN AND METHODS Lower body negative pressure of 30 cm H2O was used to create rapid hypovolemic stress in 15 young women with type 1 diabetes (DW) and 16 healthy women (control subjects [C]). Compensatory mobilization of venous capacitance blood (capacitance response) and net fluid absorption from tissue to blood were measured with a volumetric technique. Overall cardiovascular responses and plasma norepinephrine levels were measured. RESULTS Capacitance response was reduced (DW, 0.67 ± 0.05; C, 0.92 ± 0.06) and developed slower in DW (P < 0.01). Capacitance response was further reduced with increasing levels of HbA1c. Fluid absorption was almost halved in DW (P < 0.01). The initial vasoconstrictor response was reduced and developed slower in DW (P < 0.05). Arterial vasoconstriction was further reduced in the presence of microvascular complications (P < 0.05). CONCLUSIONS DW present with decreased and slower mobilization of venous capacitance blood and decreased net fluid absorption from tissue to blood during hypovolemic circulatory stress. Collectively, this indicates that DW are prone to hemodynamic instability, especially in the presence of microvascular complications and poor glycemic control.
Collapse
|
10
|
The effect of positive end-expiratory pressure and tripled tidal volume on pleth variability index during hypovolaemia in conscious subjects. Eur J Anaesthesiol 2013; 30:671-7. [DOI: 10.1097/eja.0b013e32836394c0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
11
|
Mellingsæter MR, Wyller VB, Wyller TB, Ranhoff AH. Gender differences in orthostatic tolerance in the elderly. Aging Clin Exp Res 2013; 25:659-65. [DOI: 10.1007/s40520-013-0092-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2013] [Accepted: 07/11/2013] [Indexed: 01/22/2023]
|
12
|
White LH, Bradley TD. Role of nocturnal rostral fluid shift in the pathogenesis of obstructive and central sleep apnoea. J Physiol 2013; 591:1179-93. [PMID: 23230237 PMCID: PMC3607865 DOI: 10.1113/jphysiol.2012.245159] [Citation(s) in RCA: 202] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Accepted: 12/06/2012] [Indexed: 12/25/2022] Open
Abstract
Obstructive sleep apnoea (OSA) is common in the general population and increases the risk of motor vehicle accidents due to hypersomnolence from sleep disruption, and risk of cardiovascular diseases owing to repetitive hypoxia, sympathetic nervous system activation, and systemic inflammation. In contrast, central sleep apnoea (CSA) is rare in the general population. Although their pathogenesis is multifactorial, the prevalence of both OSA and CSA is increased in patients with fluid retaining states, especially heart failure, where they are associated with increased mortality risk. This observation suggests that fluid retention may contribute to the pathogenesis of both OSA and CSA. According to this hypothesis, during the day fluid accumulates in the intravascular and interstitial spaces of the legs due to gravity, and upon lying down at night redistributes rostrally, again owing to gravity. Some of this fluid may accumulate in the neck, increasing tissue pressure and causing the upper airway to narrow, thereby increasing its collapsibility and predisposing to OSA. In heart failure patients, with increased rostral fluid shift, fluid may additionally accumulate in the lungs, provoking hyperventilation and hypocapnia, driving below the apnoea threshold, leading to CSA. This review article will explore mechanisms by which overnight rostral fluid shift, and its prevention, can contribute to the pathogenesis and therapy of sleep apnoea.
Collapse
Affiliation(s)
- Laura H White
- Department of Medicine, University Health Network Toronto General Hospital, Rehabilitation Institute, University of Toronto, Ontario, Canada
| | | |
Collapse
|
13
|
Reduced Defense of Central Blood Volume During Acute Lower Body Negative Pressure–Induced Hypovolemic Circulatory Stress in Aging Women. Shock 2012; 37:579-85. [DOI: 10.1097/shk.0b013e31824fbb3e] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
14
|
Edgell H, Robertson AD, Hughson RL. Hemodynamics and brain blood flow during posture change in younger women and postmenopausal women compared with age-matched men. J Appl Physiol (1985) 2012; 112:1482-93. [DOI: 10.1152/japplphysiol.01204.2011] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Increased incidence of orthostatic hypotension and presyncopal symptoms in young women could be related to hormonal factors that might be isolated by comparing cardiovascular and cerebrovascular responses to postural change in young and older men and women. Seven young women, 11 young men, 10 older women (>1 yr postmenopausal, no hormone therapy), and 9 older men participated in a supine-to-sit-to-stand test while measuring systemic hemodynamics, end-tidal Pco2, and blood flow velocity of the middle cerebral artery (MCA). Women had a greater reduction in stroke volume index compared with age-matched men (change from supine to standing: young women: −22.9 ± 1.6 ml/m2; young men: −14.4 ± 2.4 ml/m2; older women: −17.4 ± 3.3 ml/m2; older men: −13.8 ± 2.2 ml/m2). This was accompanied by offsetting changes in heart rate, particularly in young women, resulting in no age or sex differences in cardiac output index. Mean arterial pressure (MAP) was higher in older subjects and increased with movement to upright postures. Younger men and women had higher forearm vascular resistance that increased progressively in the upright posture compared with older men and women. There was no difference between sexes or ages in total peripheral resistance index. Women had higher MCA velocity, but both sexes had reduced MCA velocity while upright, which was a function of reduced blood pressure at the MCA and a significant reduction in end-tidal Pco2. The reductions in stroke volume index suggested impaired venous return in women, but augmented responses of heart rate and forearm vascular resistance protected MAP in younger women. Overall, these results showed significant sex and age-related differences, but compensatory mechanisms preserved MAP and MCA velocity in young women.
Collapse
Affiliation(s)
- H. Edgell
- Faculty of Applied Health Sciences, University of Waterloo, Waterloo, Ontario; and
- Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - A. D. Robertson
- Faculty of Applied Health Sciences, University of Waterloo, Waterloo, Ontario; and
| | - R. L. Hughson
- Faculty of Applied Health Sciences, University of Waterloo, Waterloo, Ontario; and
| |
Collapse
|
15
|
Lindenberger M, Olsen H, Lanne T. Impaired compensatory response to hypovolaemic circulatory stress in type 1 diabetes mellitus. Diab Vasc Dis Res 2011; 8:136-42. [PMID: 21562065 DOI: 10.1177/1479164111404576] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Diabetes mellitus is associated with decreased haemodynamic stability and reduced tolerance to hypovolaemia. Compensatory haemodynamic responses during experimental hypovolaemia in type 1 diabetes patients with (DMR+) and without (DMR-) retinopathy as well as healthy controls (C) were studied. Lower body negative pressure created hypovolaemic circulatory stress. Volumetric techniques were used to assess the compensatory capacitance response (redistribution of peripheral venous blood to the central circulation) and to assess capillary fluid absorption from tissue to blood. The compensatory capacitance response was 1/3 lower in DMR+ compared with C (p = 0.002) and DMR- (p = 0.01). Net capillary fluid absorption was reduced by one-third in DMR- and DMR+ compared with C (each p < 0.05). Type 1 diabetes patients with retinopathy demonstrate reduced mobilisation of peripheral venous blood to the central circulation. Furthermore, type 1 diabetes patients present with impaired capillary fluid absorption, which in combination with potentially decreased sympathetic vasoconstriction impedes cardiovascular homeostasis during acute hypovolaemic stress.
Collapse
Affiliation(s)
- Marcus Lindenberger
- Division of Cardiovascular Medicine, Department of Medical and Health Sciences, Linköping University, Sweden.
| | | | | |
Collapse
|
16
|
Zachrisson H, Lindenberger M, Hallman D, Ekman M, Neider D, Länne T. Diameter and compliance of the greater saphenous vein - effect of age and nitroglycerine. Clin Physiol Funct Imaging 2011; 31:300-6. [DOI: 10.1111/j.1475-097x.2011.01016.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
17
|
Avin KG, Naughton MR, Ford BW, Moore HE, Monitto-Webber MN, Stark AM, Gentile AJ, Law LAF. Sex differences in fatigue resistance are muscle group dependent. Med Sci Sports Exerc 2011; 42:1943-50. [PMID: 20195184 DOI: 10.1249/mss.0b013e3181d8f8fa] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE Women are often reported to be generally more resistant to fatigue than men for relative-intensity tasks. This has been observed repeatedly for elbow flexors, whereas at the ankle, sex differences appear less robust, suggesting localized rather than systemic influences. Thus, the purpose of this study was to examine sex differences in fatigue resistance at muscle groups in a single cohort and which factors, if any, predict endurance time. METHODS Thirty-two young adults (age = 19-44 yr, 16 women) performed sustained isometric contractions at 50% maximum voluntary isometric contraction to failure for elbow flexion and ankle dorsiflexion. Pain, exertion, and muscle EMG were assessed throughout. Self-reported baseline activity was measured using the International Physical Activity Questionnaire. RESULTS Women were significantly more resistant to fatigue than men at the elbow (112.3 ± 6.2 vs 80.3 ± 5.8 s, P = 0.001) but not at the ankle (140.6 ± 10.7 vs 129.2 ± 10.5 s, P = 0.45). Peak torque was greater in men than that in women (P < 0.0001) at the ankle (45.0 ± 1.7 vs 30.1 ± 1.0 N·m) and at the elbow (75.7 ± 3.1 vs 34.4 ± 2.2 N·m). Peak torque was significantly related to endurance time at the elbow (R2= 0.30) but not at the ankle (R2 = 0.03). Peak pain, rate of pain increase, peak exertion, EMG, and baseline physical activity did not differ between sexes. CONCLUSIONS Sex differences in fatigue resistance are muscle group specific. Women were more fatigue resistant at the elbow but not at the ankle during a sustained isometric contraction. Further, factors that may contribute to fatigue resistance for one muscle group (e.g., sex, peak torque) may not be critical at another.
Collapse
Affiliation(s)
- Keith G Avin
- Graduate Program in Physical Therapy and Rehabilitation Science, The University of Iowa, Iowa City, IA 52242-1190, USA
| | | | | | | | | | | | | | | |
Collapse
|
18
|
Nilsson L, Goscinski T, Lindenberger M, Länne T, Johansson A. Respiratory variations in the photoplethysmographic waveform: acute hypovolaemia during spontaneous breathing is not detected. Physiol Meas 2010; 31:953-62. [DOI: 10.1088/0967-3334/31/7/006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
19
|
Using the Finometer to examine sex differences in hemodynamic responses to orthostasis in older people. Blood Press Monit 2010; 15:8-17. [DOI: 10.1097/mbp.0b013e3283353199] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
20
|
Lindenberger M, Olsen H, Länne T. Lower capacitance response and capillary fluid absorption in women to defend central blood volume in response to acute hypovolemic circulatory stress. Am J Physiol Heart Circ Physiol 2008; 295:H867-73. [DOI: 10.1152/ajpheart.00332.2008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Acute hemorrhage is a leading cause of death in trauma, and women are more susceptible to hypovolemic circulatory stress than men. The mechanisms underlying the susceptibility are not clear, however. The aim of the present study was to examine the compensatory mechanisms to defend central blood volume during experimental hypovolemia in women and men. Twenty-two women (23.1 ± 0.4 yr) and 16 men (23.2 ± 0.5 yr) were included. A lower body negative pressure (LBNP) of 11–44 mmHg induced experimental hypovolemic circulatory stress. The volumetric technique was used to assess the capacitance response (redistribution of peripheral venous blood to the central circulation) as well as to assess net capillary fluid transfer from tissue to blood in the arm. Plasma norepinephrine (NE) and forearm blood flow were measured before and during hypovolemia, and forearm vascular resistance (FVR) was calculated. LBNP created comparable hypovolemia in women and men. FVR increased less in women during hypovolemic stress, and no association between plasma NE and FVR was seen in women ( R2 = 0.01, not significant), in contrast to men ( R2 = 0.59, P < 0.05). Women demonstrated a good initial capacitance response, but this was not maintained with time, in contrast to men [e.g., decreased by 24 ± 4% (women) vs. 4 ± 5% (men), LBNP of 44 mmHg, P < 0.01], and net capillary fluid absorption from tissue to blood was lower in women (0.086 ± 0.007 vs. 0.115 ± 0.011 ml·100 ml−1·min−1, P < 0.05). In conclusion, women showed impaired vasoconstriction, reduced capacitance response with time, and reduced capillary fluid absorption during acute hypovolemic circulatory stress, indicating less efficiency to defend central blood volume than men.
Collapse
|