-
Experimental Physiology Sep 2020
Topics: Hemodynamics; Humans; Microcirculation; Oxygen
PubMed: 33448480
DOI: 10.1113/EP088912 -
Critical Care (London, England) Jul 2019The endothelial glycocalyx (eGC) covers the luminal surface of the vascular endothelium and plays an important protective role in systemic inflammatory states and... (Observational Study)
Observational Study
BACKGROUND
The endothelial glycocalyx (eGC) covers the luminal surface of the vascular endothelium and plays an important protective role in systemic inflammatory states and particularly in sepsis. Its breakdown leads to capillary leak and organ dysfunction. Moreover, sepsis-induced alterations of sublingual microcirculation are associated with a worse clinical outcome. The present study was performed to investigate the associations between eGC dimensions and established parameters of microcirculation dysfunction in sepsis.
METHODS
This observational, prospective, cross-sectional study included 40 participants, of which 30 critically ill septic patients were recruited from intensive care units of a university hospital and 10 healthy volunteers served as controls. The established microcirculation parameters were obtained sublingually and analyzed according to the current recommendations. In addition, the perfused boundary region (PBR), an inverse parameter of the eGC dimensions, was measured sublingually, using novel data acquisition and analysis software (GlycoCheck™). Moreover, we exposed living endothelial cells to 5% serum from a subgroup of study participants, and the delta eGC breakdown, measured with atomic force microscopy (AFM), was correlated with the paired PBR values.
RESULTS
In septic patients, sublingual microcirculation was impaired, as indicated by a reduced microvascular flow index (MFI) and a reduced proportion of perfused vessels (PPV) compared to those in healthy controls (MFI, 2.93 vs 2.74, p = 0.002; PPV, 98.53 vs 92.58, p = 0.0004). PBR values were significantly higher in septic patients compared to those in healthy controls, indicating damage of the eGC (2.04 vs 2.34, p < 0.0001). The in vitro AFM data correlated exceptionally well with paired PBR values obtained at the bedside (rs = - 0.94, p = 0.02). Both PBR values and microcirculation parameters correlated well with the markers of critical illness. Interestingly, no association was observed between the PBR values and established microcirculation parameters.
CONCLUSION
Our findings suggest that eGC damage can occur independently of microcirculatory impairment as measured by classical consensus parameters. Further studies in critically ill patients are needed to unravel the relationship of glycocalyx damage and microvascular impairment, as well as their prognostic and therapeutic importance in sepsis.
TRIAL REGISTRATION
Retrospectively registered: Clinicaltrials.gov, NCT03960307.
Topics: Adult; Aged; Aged, 80 and over; Biomarkers; Cross-Sectional Studies; Endothelial Cells; Female; Glycocalyx; Humans; Male; Microcirculation; Middle Aged; Prospective Studies; Resuscitation; Retrospective Studies; Sepsis
PubMed: 31340868
DOI: 10.1186/s13054-019-2542-2 -
Renal Failure Dec 2024Renal microcirculation plays a pivotal role in kidney function by maintaining structural and functional integrity, facilitating oxygen and nutrient delivery, and waste...
BACKGROUND
Renal microcirculation plays a pivotal role in kidney function by maintaining structural and functional integrity, facilitating oxygen and nutrient delivery, and waste removal. However, a thorough bibliometric analysis in this area remains lacking. Therefore, we aim to provide valuable insights through a bibliometric analysis of renal microcirculation literature using the Web of Science database.
METHODS
We collected renal microcirculation-related publications from the Web of Science database from January 01, 1990, to December 31, 2022. The co-authorship of authors, organizations, and countries/regions was analyzed with VOSviewer1.6.18. The co-occurrence of keywords and co-cited references were analyzed using CiteSpace6.1.R6 software to generate visualization maps. Additionally, burst detection was applied to keywords and cited references to forecast research hotspots and future trends.
RESULTS
Our search yielded 7462 publications, with the American Journal of Physiology-Renal Physiology contributing the most articles. The United States, Mayo Clinic, and Lerman Lilach O emerged with the highest publication count, indicating their active collaborations. 'Type 2 diabetes' was the most significant keyword cluster, and 'diabetic kidney disease' was the largest cluster of cited references. 'Cardiovascular outcome' and 'diabetic kidney diseases' were identified as keywords in their burst period over the past three years.
CONCLUSION
Our bibliometric analysis illuminates the contours of nephrology and microcirculation research, revealing a landscape ripe for challenges and the seeds of future scientific innovation. While the trends discerned from the literature emerging opportunities in diagnostic innovation, renal microcirculation research, and precision medicine interventions, their translation to clinical practice is anticipated to be a deliberate process.
Topics: Humans; Microcirculation; Kidney; Diabetic Nephropathies; Bibliometrics; Databases, Factual
PubMed: 38482598
DOI: 10.1080/0886022X.2024.2329249 -
Physiology (Bethesda, Md.) Sep 2018To date, the major focus of diagnostic modalities and interventions to treat coronary artery disease has been the large epicardial vessels. Despite substantial data... (Review)
Review
To date, the major focus of diagnostic modalities and interventions to treat coronary artery disease has been the large epicardial vessels. Despite substantial data showing that microcirculatory dysfunction is a strong predictor of future adverse cardiovascular events, very little research has gone into developing techniques for in vivo diagnosis and therapeutic interventions to improve microcirculatory function. In this review, we will discuss the pathophysiology of coronary arteriolar dysfunction, define its prognostic implications, evaluate the diagnostic modalities available, and provide speculation on current and potential therapeutic opportunities.
Topics: Animals; Arterioles; Cardiovascular Diseases; Coronary Artery Disease; Humans; Microcirculation; Microvessels; Prognosis
PubMed: 30109826
DOI: 10.1152/physiol.00019.2018 -
Biomedical and Environmental Sciences :... Apr 2022This study aimed to examine the effects of microcirculatory dysfunction and 654-1 intervention after cardiopulmonary resuscitation on myocardial injury.
OBJECTIVE
This study aimed to examine the effects of microcirculatory dysfunction and 654-1 intervention after cardiopulmonary resuscitation on myocardial injury.
METHODS
Landrace pigs were divided into a sham operation group (S group, = 6), ventricular fibrillation control group (VF-C group, = 8) and 654-1 intervention group (VF-I group, = 8). Hemodynamics was recorded at baseline, at recovery of spontaneous circulation (ROSC), and 1 h, 2 h, 4 h and 6 h thereafter. Sidestream dark field (SDF) technology was used to evaluate and monitor the microcirculation flow index, total vessel density, perfusion vessel ratio, De-Backer score, and perfusion vessel density in animal viscera at various time points.
RESULTS
After administration of 654-1 at 1.5 h post-ROSC, the hemodynamics in the VF-I group, as compared with the VF-C group, was significantly improved. The visceral microcirculation detected by SDF was also significantly improved in the VF-I group. As observed through electron microscopy, significantly less myocardial tissue injury was present in the VF-I group than the VF-C group.
CONCLUSION
Administration of 654-1 inhibited excessive inflammatory by improving the state of visceral microcirculation.
Topics: Animals; Cardiopulmonary Resuscitation; Microcirculation; Swine; Ventricular Fibrillation
PubMed: 35473897
DOI: 10.3967/bes2022.044 -
BMC Anesthesiology Oct 2016Thoracic epidural analgesia (TEA) is used for pain relief during and after abdominal surgery, but the effect of TEA on the splanchnic microcirculation remains debated....
BACKGROUND
Thoracic epidural analgesia (TEA) is used for pain relief during and after abdominal surgery, but the effect of TEA on the splanchnic microcirculation remains debated. We evaluated whether TEA affects splanchnic microcirculation in the pig.
METHODS
Splanchnic microcirculation was assessed in nine pigs prior to and 15 and 30 min after induction of TEA. Regional blood flow was assessed by neutron activated microspheres and changes in microcirculation by laser speckle contrast imaging (LSCI).
RESULTS
As assessed by LSCI 15 min following TEA, gastric arteriolar flow decreased by 22 % at the antrum (p = 0.020) and by 19 % at the corpus (p = 0.029) of the stomach. In parallel, the microcirculation decreased by 19 % at the antrum (p = 0.015) and by 20 % at the corpus (p = 0.028). Reduced arteriolar flow and microcirculation at the antrum was confirmed by a reduction in microsphere assessed regional blood flow 30 min following induction of TEA (p = 0.048). These manifestations took place along with a drop in systolic blood pressure (p = 0.030), but with no significant change in mean arterial pressure, cardiac output, or heart rate.
CONCLUSION
The results indicate that TEA may have an adverse effect on gastric arteriolar blood flow and microcirculation. LSCI is a non-touch technique and displays changes in blood flow in real-time and may be important for further evaluation of the concern regarding the effect of thoracic epidural anesthesia on gastric microcirculation in humans.
TRIAL REGISTRATIONS
Not applicable, non-human study.
Topics: Analgesia, Epidural; Animals; Blood Pressure; Cardiac Output; Female; Heart Rate; Microcirculation; Regional Blood Flow; Splanchnic Circulation; Swine; Thoracic Vertebrae; Time Factors
PubMed: 27716081
DOI: 10.1186/s12871-016-0256-4 -
Aging Nov 2017
Topics: Humans; Insulin; Insulin Resistance; Liver; Microcirculation
PubMed: 29140795
DOI: 10.18632/aging.101330 -
Diving and Hyperbaric Medicine Dec 2021Hyperbaric oxygen (HBO) exposure for 10-15 min has been shown to reduce peripheral blood flow due to vasoconstriction. However, the relationship between decreased...
INTRODUCTION
Hyperbaric oxygen (HBO) exposure for 10-15 min has been shown to reduce peripheral blood flow due to vasoconstriction. However, the relationship between decreased peripheral blood flow and the therapeutic effects of HBO treatment on peripheral circulatory disorders remain unknown. Longer exposures have been reported to have vasodilatory effects and increase peripheral blood flow. This study investigated the effect of HBO treatment on blood flow and transcutaneous oxygen pressure (TcPO).
METHODS
Twenty healthy volunteers aged 20-65 years (nine males) participated in this study. All participants breathed oxygen for 60 min at 253.3 kPa. Peripheral blood flow using laser Doppler flowmetry and TcPO on the ear, hand, and foot were continuously measured from pre-HBO exposure to 10 min post-exposure.
RESULTS
Peripheral blood flow in each body part decreased by 7-23% at the beginning of the HBO exposure, followed by a slow increase. Post-exposure, peripheral blood flow increased 4-76% in each body part. TcPO increased by 840-1,513% during the exposure period, and remained elevated for at least 10 min after the exposure.
CONCLUSIONS
The findings of the current study suggest vasoconstriction during HBO treatment is transient, and even when present does not inhibit the development of increased tissue oxygen partial pressure. These findings are relevant to studies investigating changes in peripheral blood flow during HBO treatment in patients with circulatory disorders.
Topics: Hand; Humans; Hyperbaric Oxygenation; Male; Microcirculation; Oxygen; Time Factors
PubMed: 34897598
DOI: 10.28920/dhm51.4.338-344 -
Science Progress 2021To investigate the characteristics of pressure ulcer microcirculation in SCI patients with pressure ulcer, and to provide evidence for the treatment of pressure ulcer in...
To investigate the characteristics of pressure ulcer microcirculation in SCI patients with pressure ulcer, and to provide evidence for the treatment of pressure ulcer in patients with SCI. Group 1 ( = 12) SCI patients with pressure ulcer, 23 pressure ulcers were included. Group 2 ( = 15) SCI patients without pressure ulcer and the control group ( = 16) healthy adults. The application of laser Doppler perfusion imaging system (Moor FLPI) detector to the microcirculation perfusion of the sacrum area of the control group, the observation group 2 and the pressure ulcer site of the observation group 1, record the microcirculation perfusion (PU), The data of microcirculation perfusion (PU) were compared and analyzed. The correlation between microcirculation perfusion and healing time of pressure ulcer was analyzed. (1) The microcirculation perfusion was highest in the pressure ulcer center. (2) SCI patients and healthy adults had no significant difference of microcirculation perfusion at sacrococcygeal skin. (3) The lower the microcirculation perfusion of the pressure ulcer center, the longer the healing time of pressure ulcer. The healing time and the microcirculation perfusion of pressure ulcer center was negatively correlated. Microcirculation perfusion detection is a noninvasive and effective method for the determination of the scope of pressure ulcer, detection and direction judgment of pressure ulcer sinus tract, monitoring and guidance of pressure ulcer treatment, and prediction of the healing time of pressure ulcer.
Topics: Adult; Humans; Microcirculation; Pressure Ulcer; Skin; Spinal Cord Injuries; Wound Healing
PubMed: 34495784
DOI: 10.1177/00368504211028726 -
Neurosurgery Apr 2022Delayed cerebral ischemia (DCI) is the most consequential secondary insult after aneurysmal subarachnoid hemorrhage (SAH). It is a multifactorial process caused by a...
BACKGROUND
Delayed cerebral ischemia (DCI) is the most consequential secondary insult after aneurysmal subarachnoid hemorrhage (SAH). It is a multifactorial process caused by a combination of large artery vasospasm and microcirculatory dysregulation. Despite numerous efforts, no effective therapeutic strategies are available to prevent DCI. The trigeminal nerve richly innervates cerebral blood vessels and releases a host of vasoactive agents upon stimulation. As such, electrical trigeminal nerve stimulation (TNS) has the capability of enhancing cerebral circulation.
OBJECTIVE
To determine whether TNS can restore impaired cerebral macrocirculation and microcirculation in an experimental rat model of SAH.
METHODS
The animals were randomly assigned to sham-operated, SAH-control, and SAH-TNS groups. SAH was induced by endovascular perforation on Day 0, followed by KCl-induced cortical spreading depolarization on day 1, and sample collection on day 2. TNS was delivered on day 1. Multiple end points were assessed including cerebral vasospasm, microvascular spasm, microthrombosis, calcitonin gene-related peptide and intercellular adhesion molecule-1 concentrations, degree of cerebral ischemia and apoptosis, and neurobehavioral outcomes.
RESULTS
SAH resulted in significant vasoconstriction in both major cerebral vessels and cortical pial arterioles. Compared with the SAH-control group, TNS increased lumen diameters of the internal carotid artery, middle cerebral artery, and anterior cerebral artery, and decreased pial arteriolar wall thickness. Additionally, TNS increased cerebrospinal fluid calcitonin gene-related peptide levels, and decreased cortical intercellular adhesion molecule-1 expression, parenchymal microthrombi formation, ischemia-induced hypoxic injury, cellular apoptosis, and neurobehavioral deficits.
CONCLUSION
Our results suggest that TNS can enhance cerebral circulation at multiple levels, lessen the impact of cerebral ischemia, and ameliorate the consequences of DCI after SAH.
Topics: Animals; Rats; Brain Ischemia; Microcirculation; Subarachnoid Hemorrhage; Trigeminal Nerve; Vasospasm, Intracranial
PubMed: 35188109
DOI: 10.1227/NEU.0000000000001854