Human ocular surface microcirculation quantified by in vivo computer assisted video microscopy and diffuse reflectance spectroscopy.

Non-invasive imaging techniques are increasingly used to objectively quantify anterior segment structures of the eye. In this study, we apply the novel oxygen delivery index (ODIN) concept that, quantifies microvascular capacity for oxygen delivery, to the ocular surface in healthy humans. The purpose of the study was to test the applicability of the technologies used for data acquisition from the human ocular surface.

Microvascular remodeling following skin injury.

Objective: The aim of this study was to describe possible remodeling (i.e., dilatation and elongation) of papillary capillaries induced by increased oxygen demand for the repair process following a skin wound.

Ocular surface microcirculation is better preserved with pulsatile versus continuous flow during cardiopulmonary bypass-An experimental pilot.

Background: Non-pulsatile cardiopulmonary bypass (CPB) may induce microvascular dysregulation. In piglets, we compared ocular surface microcirculation during pulsatile versus continuous flow (CF) bypass.

Methods: Ocular surface microcirculation in small tissue volumes (~0.

Hemodynamic evaluation of a new pulsatile blood pump during low flow cardiopulmonary bypass support.

Background: The VentriFlo True Pulse Pump (VentriFlo, Inc, Pelham, NH, USA) is a new pulsatile blood pump intended for use during short-term circulatory support. The purpose of this study was to evaluate the feasibility of the VentriFlo and compare it to a conventional centrifugal pump (ROTAFLOW, Getinge, Gothenberg, Sweden) in acute pig experiments.

Methods: Pigs (40-45 kg) were supported by cardiopulmonary bypass (CPB) with the VentriFlo (n = 9) or ROTAFLOW (n = 5) for 6 h.

Skin trauma rapidly induces thermoregulatory plexus hyperemia, while an increased nutritive papillary capillary function can be detected after 24 h.

Objective: Clinical assessments and laser Doppler perfusion measurements (LDPM) of skin microcirculation have limited value, as they fail to capture events regulated by local metabolic needs at a papillary capillary level. This study aimed to examine the ability of computer-assisted video microscopy (CAVM) and diffuse reflectance spectroscopy (DRS) to assess skin nutritive perfusion-compared to LDPM.

Methods: Healthy volunteers (n = 10) were examined after (≈1 and ≈24 h) an incision (5 × 1 mm) on the forearm, at 0.

Intraperitoneal microdialysis detects intestinal leakage earlier than hemodynamic surveillance and systemic inflammation in a pig model.

Objective: Anastomotic leakage is a common complication following large abdominal surgery, often developing to life-threatening abdominal sepsis due to late diagnosis. Currently, diagnostics rely on systemic hemodynamic and infection monitoring. We hypothesized that intraperitoneal microdialysis allows detection of peritonitis prior to changes in standard clinical parameters in a pig model.

Quantification of ocular surface microcirculation by computer assisted video microscopy and diffuse reflectance spectroscopy.

In piglets we tested the applicability of digital video microscopy and diffuse reflectance spectroscopy for non-invasive assessments of limbal and bulbar conjunctival microcirculation. A priori we postulated that the metabolic rate is higher in limbal as compared to bulbar conjunctiva, and that this difference is reflected in microvascular structure or function between the two locations. Two study sites, Oslo University Hospital (OUH), Norway and Cleveland Clinic (CC), USA, used the same video microscopy and spectroscopy techniques to record limbal and bulbar microcirculation in sleeping piglets.

Acute skin trauma induces hyperemia, but superficial papillary nutritive perfusion remains unchanged.

Objectives: Superficial skin papillary capillaries with blood supply from a superficial vascular plexus and regulated by local metabolic needs supply oxygen and nutrients for epithelial cell proliferation. A deep vascular plexus regulated by autonomous nerves serves body thermoregulation. In healthy volunteers, we assessed circulatory effects of a standardized skin trauma by CAVM, DRS, and LDPM to assess the measuring depth of the three techniques and to describe the acute trauma effects on nutritive and thermoregulatory perfusion.

Noninvasive assessments of oxygen delivery from the microcirculation to skin in hypothermia-treated asphyxiated newborn infants.

Background: Therapeutic hypothermia (TH) has become standard treatment for severe and moderate hypoxic-ischemic neonatal encephalopathy (HIE). Our group has developed an optically based, noninvasive concept of assessing the capacity for oxygen delivery from the microcirculation to the cells of a tissue under investigation. The hypothesis was that mechanisms of reduced oxygen delivery due to reduced metabolism in cooled asphyxiated neonates could be characterized with this concept.

Specific changes in conduction velocity recovery cycles of single nociceptors in a patient with erythromelalgia with the I848T gain-of-function mutation of Nav1.7.

Seven patients diagnosed with erythromelalgia (EM) were investigated by microneurography to record from unmyelinated nerve fibers in the peroneal nerve. Two patients had characterized variants of sodium channel Nav1.7 (I848T, I228M), whereas no mutations of coding regions of Navs were found in 5 patients with EM.

Skin microcirculation in healthy term newborn infants--assessment of morphology, perfusion and oxygenation.

Unlabelled: Despite microcirculation's fundamental role, assessments of its function are limited. We explored the applicability of Computer Assisted Video Microscope (CAVM), Laser Doppler Perfusion Measurements (LDPM) and Diffuse Reflectance Spectroscopy (DRS) to study skin microvascular morphology, perfusion and oxygen saturation in twenty-five healthy newborns day 1-3 of life.

Results: Day 1-3 (mean (SD)): Microvascular density (CAVM; number of microvessels crossing a grid of lines/mm line, c/mm): Chest: 11.

Skin microvascular morphology and hemodynamics during treatment with veno-arterial extra-corporeal membrane oxygenation.

Objectives: To explore the potentials of microcirculatory assessments for predicting outcome of patients treated with extra corporeal membrane oxygenation for cardiogenic shock.

Methods: Eight patients with acute cardiogenic shock treated with ECMO and eight healthy controls were examined with skin vital microscopy and laser Doppler perfusion measurements.

Results: Three patients died on ECMO (group 1).

Diffuse reflectance spectroscopy: Systemic and microvascular oxygen saturation is linearly correlated and hypoxia leads to increased spatial heterogeneity of microvascular saturation.

The microvascular oxygen saturation (SmvO(2)) in the skin and tongue (sublingual mucosa) in pigs (n=6) was characterised using diffuse reflectance spectroscopy (DRS). The correlation between arterial oxygen saturation (SaO(2)) and SmvO(2) as well as the spatial heterogeneity of SmvO(2) was examined during hypoxia. DRS uses shallow-penetrating visible light to assess microvascular oxygen saturation (SmvO(2)) in superficial tissue.

Assessments of skin and tongue microcirculation reveals major changes in porcine sepsis.

Aim:   To examine the relation between central hemodynamics, clinical severity and microvascular findings in tongue and skin during sepsis.

Materials And Methods:   Skin and tongue microcirculation was examined using laser Doppler and video microscopy techniques before and 200 min after inducing sepsis in pigs (n=6) by inactivated Neisseria meningitides and in two control animals.

Results:   All infected pigs developed clinical signs of sepsis.

Nonspecific capillary proliferation and vasculopathy indicate skin hypoxia in erythromelalgia.

Objective: To report on the histopathologic findings of affected skin in consecutively collected biopsy specimens from 49 patients with erythromelalgia (EM).

Design: Skin biopsy specimens were obtained from the foot arch and analyzed by light microscopy, immunofluorescence microscopy, and electron microscopy.

Setting: Oslo University Hospital-Gaustad, University of Oslo, Oslo, Norway.

Human microvascular imaging: a review of skin and tongue videomicroscopy techniques and analysing variables.

Imaging techniques are increasingly important in clinical diagnostic work. Microcirculation is essential for function and survival of all tissues, but imaging techniques for microvascular monitoring of patients have only been used to a limited extent in clinical practice. The microcirculation is complex with its static and dynamic feature, and only skin and oral mucosa are readily accessible for microscopic examination.

Sevoflurane-induced malignant hyperthermia during cardiopulmonary bypass and moderate hypothermia.

A 56-year old man was admitted for elective mitral valve repair and coronary artery bypass surgery due to mitral valve leakage and unstable angina. After induction of anaesthesia he developed a combined metabolic and respiratory acidosis. Different diagnosis were considered and we decided to treat the patient with dantrolene due to suspicion of malignant hyperthermia (MH).

Pain in primary erythromelalgia--a neuropathic component?

Erythromelalgia is a condition characterized by attacks of red, hot, painful extremities with relief of symptoms by cooling and aggravation by warmth. Although the main emphasis has been on pathophysiological mechanisms related to circulatory changes, recent reports have focused on an involvement of efferent small nerve fibers indicating a neuropathic component. Since the symptoms resemble those described in neuropathic pain, we wanted to investigate the possible affection of afferent nerve fibers.

The prostaglandin E1 analog misoprostol reduces symptoms and microvascular arteriovenous shunting in erythromelalgia-a double-blind, crossover, placebo-compared study.

Based on previous experience with parenteral prostanoids, we studied the effect of misoprostol treatment, an orally administered prostaglandin E1 analog, in patients with erythromelalgia. Treatment with placebo was followed by treatment with misoprostol (0.4-0.

Prostacyclin reduces symptoms and sympathetic dysfunction in erythromelalgia in a double-blind randomized pilot study.

Sympathetic dysfunction and skin microvascular arteriovenous shunting with insufficient nutritive perfusion and tissue hypoxia have been reported in patients with erythromelalgia. The objective of this study was to determine whether iloprost, a synthetic prostacyclin analogue--primarily a vasodilator and inhibitor of platelet activation--improves symptoms and sympathetic function in patients with erythromelalgia. Erythromelalgia is a rare condition, but we managed to collect 12 primary cases for a double-blind, randomized, parallel-group pilot trial evaluating the effect of iloprost (n = 8) and placebo (n = 4).

Myocardial extracellular signal regulatory kinases are activated by laser treatment.

Aim: Transmyocardial laser revascularization (TMR) and percutaneous transluminal myocardial laser revascularization (PTMR) have anti-anginal effects on certain groups of patients with ischemic heart disease, possibly by inducing myocardial neoangiogenesis through the mechanical injury. Here we examine the effects of TMR and PTMR on extracellular signal regulatory kinases (ERKs), which have been implicated in the control of neoangiogenesis in vitro.

Methods: Eight pigs were anesthetized with ketamine and fentanyl.

[Preoperative expectations and clinical outcome of transmyocardial laser treatment in patients with angina pectoris].

Background: The aims of this study were to evaluate the effect of transmyocardial laser treatment on quality of life and to assess the correlation between preoperative expectations and clinical improvement after one year.

Material And Methods: 13 patients (median age 56 years) with disabling angina pectoris were subjected to transmyocardial holmium: YAG laser. Quality of life was assessed preoperatively and at three and 12 months by Hospital Anxiety and Depression Scale (HAD), Physical Symptom Distress Index (PSDI) and Life Satisfaction Index (LSI).

Reduced skin capillary density during attacks of erythromelalgia implies arteriovenous shunting as pathogenetic mechanism.

Erythromelalgia is characterized by burning pain, erythema, and increased temperature in acral skin. The pain is aggravated by warming and relieved by cooling. Increased microvascular arteriovenous shunting in deep dermal plexa has been hypothesized as the pathogenetic mechanism of pain in affected skin, inducing hypoxia during pain attacks.

Impaired neurogenic control of skin perfusion in erythromelalgia.

Erythromelalgia is a clinical diagnosis characterized by erythema, increased temperature and burning pain in acral skin. The pain is relieved by cooling and aggravated by warming. The symptoms have been hypothesized to be caused by skin hypoxia due to increased arteriovenous shunting.