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1.
Vestn Oftalmol ; 138(3): 41-45, 2022.
Article in Russian | MEDLINE | ID: covidwho-1934754

ABSTRACT

PURPOSE: To evaluate the severity of hemodynamic changes in the ocular vessels of patients recovered from COVID-19. MATERIAL AND METHODS: The study included 44 patients (88 eyes) aged 28-60 years, among them 24 (54.5%) women and 20 (45.4%) men, with SARS-CoV-2 infection confirmed by PCR no more than 2 months prior to enrollment and with no ophthalmological complaints within 2 months before the disease, as well as 20 healthy volunteers (40 eyes). At the time of the study all patients had a negative PCR result for SARS-CoV-2. The patients were divided into 2 groups. The first group comprised 24 patients who did not take any anticoagulants during the treatment. The second group consisted of 20 patients who received anticoagulants (Rivaroxaban (Xarelto)) at a dosage of 10 mg per day for 1-1.5 months. The maximum systolic (Vs), end-diastolic (Vd) blood flow velocity, as well as resistance index (RI) in the ophthalmic artery (OA), central retinal artery (CRA) and short posterior ciliary arteries (SPCA) were measured in all study patients with the ultrasound imaging system VOLUSON E8 Expert («Kretz¼, USA). Additionally, the flowmetry method was used to assess the volumetric ocular blood flow (VOBF) on Ocular Blood Flow Analyzer system («Paradigm Medical Industries, Inc.¼, USA). RESULTS: In the first group, a decrease in Vs and Vd was noted amid a significant increase of RI in CRA and SPCA, as well as an increase of RI in OA compared with the age-normal values (p<0.05). In the second group, a decrease in Vs and Vd was noted amid a significant increase of RI in CRA, as well as a decrease in Vs in SPCA and an increase of RI in OA relative to the age-normal values (p<0.05). A decrease in VOBF was noted in the first group in comparison to the second group and the age norm (p<0.05). CONCLUSION: Blood flow velocity parameters in the ocular vessels are reduced in patients recovered from COVID-19 compared to the age-normal values. There was a significant decrease in volumetric ocular blood flow parameters in COVID-19 patients who did not take any anticoagulants compared to the age-normal values. Anticoagulants intake has a positive impact on hemodynamic characteristics in the ocular vessels and volumetric ocular blood flow in patients with COVID-19.


Subject(s)
COVID-19 , Retinal Artery , Anticoagulants , Blood Flow Velocity/physiology , Female , Hemodynamics , Humans , Male , Ophthalmic Artery/diagnostic imaging , Ophthalmic Artery/physiology , Regional Blood Flow/physiology , Retinal Artery/diagnostic imaging , SARS-CoV-2 , Ultrasonography, Doppler, Color
2.
Exp Physiol ; 107(7): 708-721, 2022 Jul.
Article in English | MEDLINE | ID: covidwho-1909553

ABSTRACT

NEW FINDINGS: What is the central question of this study? Are central and peripheral haemodynamics during handgrip exercise different in young adults 3-4 weeks following infection with of SARS-CoV-2 compared with young healthy adults. What is the main finding and its importance? Exercising heart rate was higher while brachial artery blood flow and vascular conductance were lower in the SARS-CoV-2 compared with the control group. These findings provide evidence for peripheral impairments to exercise among adults with SARS-CoV-2, which may contribute to exercise limitations. ABSTRACT: The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can have a profound impact on vascular function. While exercise intolerance may accompany a variety of symptoms associated with SARS-CoV-2 infection, the impact of SARS-CoV-2 on exercising blood flow (BF) remains unclear. Central (photoplethysmography) and peripheral (Doppler ultrasound) haemodynamics were determined at rest and during rhythmic handgrip (HG) exercise at 30% and 45% of maximal voluntary contraction (MVC) in young adults with mild symptoms 25 days after testing positive for SARS-CoV-2 (SARS-CoV-2: n = 8M/5F; age: 21 ± 2 years; height: 176 ± 11 cm; mass: 71 ± 11 kg) and were cross-sectionally compared with control subjects (Control: n = 8M/5F; age: 27 ± 6 years; height: 178 ± 8 cm; mass: 80 ± 25 kg). Systolic blood pressure, end systolic arterial pressure and rate pressure product were higher in the SARS-CoV-2 group during exercise at 45% MVC compared with controls. Brachial artery BF was lower in the SARS-CoV-2 group at both 30% MVC (Control: 384.8 ± 93.3 ml min-1 ; SARS-CoV-2: 307.8 ± 105.0 ml min-1 ; P = 0.041) and 45% MVC (Control: 507.4 ± 109.9 ml min-1 ; SARS-CoV-2: 386.3 ± 132.5 ml min-1 ; P = 0.002). Brachial artery vascular conductance was lower at both 30% MVC (Control: 3.93 ± 1.07 ml min-1  mmHg-1 ; SARS-CoV-2: 3.11 ± 0.98 ml min-1  mmHg-1 ; P = 0.022) and 45% MVC (Control: 4.74 ± 1.02 ml min-1  mmHg-1 ; SARS-CoV-2: 3.46 ± 1.10 ml min-1  mmHg-1 ; P < 0.001) in the SARS-CoV-2 group compared to control group. The shear-induced dilatation of the brachial artery increased similarly across exercise intensities in the two groups, suggesting the decrease in exercising BF may be due to microvascular impairments. Brachial artery BF is attenuated during HG exercise in young adults recently diagnosed with mild SARS-CoV-2, which may contribute to diminished exercise capacity among those recovering from SARS-CoV-2 like that seen in severe cases.


Subject(s)
COVID-19 , SARS-CoV-2 , Adult , Brachial Artery/physiology , Hand Strength/physiology , Hemodynamics , Humans , Muscle, Skeletal/blood supply , Regional Blood Flow/physiology , Young Adult
3.
Ann Vasc Surg ; 76: 285-288, 2021 Oct.
Article in English | MEDLINE | ID: covidwho-1525691

ABSTRACT

The arterial revascularization procedure is still a challenging issue in Covid-19 associated limb ischemia. Herein we aimed to present a case of a 64 year-old woman with acute ischemic signs in upper extremity who was diagnosed as a probable Covid-19 case incidentally after admission. Although late admission and failed recurrent embolectomies lead to an eventful course, intra-arterial thrombolysis seemed to present a benefitable treatment option for our patient.


Subject(s)
COVID-19/complications , Ischemia/etiology , Upper Extremity/blood supply , Acute Disease , Amputation , COVID-19/diagnosis , Embolectomy , Female , Humans , Ischemia/diagnostic imaging , Ischemia/physiopathology , Ischemia/therapy , Middle Aged , Regional Blood Flow , Thrombolytic Therapy , Time-to-Treatment , Treatment Outcome
4.
J Sport Rehabil ; 31(1): 77-84, 2022 01 01.
Article in English | MEDLINE | ID: covidwho-1483964

ABSTRACT

CONTEXT: Recently, blood flow restriction (BFR) training has gained popularity as an alternative to high-load resistance training for improving muscle strength and hypertrophy. Previous BFR studies have reported positive treatment effects; however, clinical benefits to using BFR following meniscal repair or chondral surgery are unknown. The purpose of this study was to determine the effect of resistance exercises with BFR training versus exercises alone on self-reported knee function, thigh circumference, and knee flexor/extensor strength postmeniscal or cartilage surgery. DESIGN: Single-blinded randomized controlled trial in an outpatient military hospital setting. Twenty participants were randomized into 2 groups: BFR group (n = 11) and control group (n = 9). METHODS: Participants completed 12 weeks of postoperative thigh strengthening. The BFR group performed each exercise with the addition of BFR. Both groups continued with the prescribed exercises without BFR from 12 weeks until discharged from therapy. Thigh circumference and self-reported knee function were measured at 1, 6, 12, and 24 weeks postoperatively along with knee extensor and flexor strength at 12 and 24 weeks. Change scores between time points were calculated for knee function. Limb symmetry indices (LSI) were computed for thigh circumference and knee strength variables. RESULTS: Seventeen participants were included in the final analyses (BFR = 8 and control = 9) due to COVID-19 restrictions. There were no interactions or main effects for group. Time main effects were established for change in knee function scores, thigh circumference LSI, and knee extensor strength LSI. However, knee flexor strength LSI had no main effect for time. CONCLUSION: The outcomes of this trial suggest that resistance exercises with and without BFR training may result in similar changes to function, thigh atrophy, and knee extensor strength postmeniscus repair/chondral restoration, though further study with larger sample sizes is needed.


Subject(s)
COVID-19 , Military Personnel , Resistance Training , Humans , Muscle Strength , Muscle, Skeletal , Muscular Atrophy , Regional Blood Flow , SARS-CoV-2
5.
Hip Int ; 30(6): 718-724, 2020 Nov.
Article in English | MEDLINE | ID: covidwho-1455854

ABSTRACT

OBJECTIVES: The posterior approach in total hip arthroplasty (THA) often requires dissection of the short external rotators (SERs), which could increase the postoperative dislocation rate. The reattachment of the dissected SERs has been reported to reduce the dislocation rate, while such repair generally causes progression of muscle atrophy. 1 of the suggested causes of atrophy is reduced blood flow to the repaired SERs. The present study aimed to measure the blood flow of the SERs before dissection (pre-tenotomy) and after reattachment (post-reattachment) during the posterior approach in THA. METHODS: This prospective study included 26 patients who underwent THA via the posterior approach. A laser-Doppler rheometer was used to measure the blood flow in the following SERs at the time of pre-tenotomy and post-reattachment: the piriformis muscle (PM), superior gemellus (SG), inferior gemellus (IG), obturator internus (OI), and subcutaneous tissue as a control. RESULTS: The average pre-tenotomy and post-reattachment blood flows (mL/minutes/100 g) were: 1.90 ± 0.28 and 1.92 ± 0.40 in the PM, 1.94 ± 0.20 and 1.99 ± 0.39 in the SG, 1.91 ± 0.21 and 1.94 ± 0.30 in the IG, 1.93 ± 0.22 and 1.98 ± 0.36 in the OI, and 1.94 ± 0.24 and 1.87 ± 0.38 in the subcutaneous tissue. The pre-tenotomy and post-reattachment blood flows did not show significant difference in any muscle. CONCLUSIONS: Laser-Doppler blood flow measurements showed that the blood flow is preserved, even when the SERs are dissected and reattached in THA via the posterior approach.


Subject(s)
Arthroplasty, Replacement, Hip/methods , Hip Dislocation/surgery , Hip Joint/surgery , Muscle, Skeletal/surgery , Regional Blood Flow/physiology , Tenotomy/methods , Aged , Aged, 80 and over , Female , Hip Joint/blood supply , Humans , Male , Middle Aged , Muscle, Skeletal/blood supply , Postoperative Period , Prospective Studies
6.
Cardiovasc Res ; 117(4): 1015-1032, 2021 03 21.
Article in English | MEDLINE | ID: covidwho-1369073

ABSTRACT

The motivation for this review comes from the emerging complexity of the autonomic innervation of the carotid body (CB) and its putative role in regulating chemoreceptor sensitivity. With the carotid bodies as a potential therapeutic target for numerous cardiorespiratory and metabolic diseases, an understanding of the neural control of its circulation is most relevant. Since nerve fibres track blood vessels and receive autonomic innervation, we initiate our review by describing the origins of arterial feed to the CB and its unique vascular architecture and blood flow. Arterial feed(s) vary amongst species and, unequivocally, the arterial blood supply is relatively high to this organ. The vasculature appears to form separate circuits inside the CB with one having arterial venous anastomoses. Both sympathetic and parasympathetic nerves are present with postganglionic neurons located within the CB or close to it in the form of paraganglia. Their role in arterial vascular resistance control is described as is how CB blood flow relates to carotid sinus afferent activity. We discuss non-vascular targets of autonomic nerves, their possible role in controlling glomus cell activity, and how certain transmitters may relate to function. We propose that the autonomic nerves sub-serving the CB provide a rapid mechanism to tune the gain of peripheral chemoreflex sensitivity based on alterations in blood flow and oxygen delivery, and might provide future therapeutic targets. However, there remain a number of unknowns regarding these mechanisms that require further research that is discussed.


Subject(s)
Arteries/innervation , Autonomic Nervous System/physiopathology , Cardiovascular Diseases/physiopathology , Carotid Body/blood supply , Hemodynamics , Oxygen/blood , Reflex , Animals , Autonomic Nervous System/metabolism , Cardiovascular Diseases/blood , Humans , Regional Blood Flow , Species Specificity
7.
Am J Physiol Heart Circ Physiol ; 321(3): H479-H484, 2021 09 01.
Article in English | MEDLINE | ID: covidwho-1322856

ABSTRACT

Recent findings suggest that COVID-19 causes vascular dysfunction during the acute phase of the illness in otherwise healthy young adults. To date, to our knowledge, no studies have investigated the longer-term effects of COVID-19 on vascular function. Herein, we hypothesized that young, otherwise healthy adults who are past the acute phase of COVID-19 would exhibit blunted peripheral [brachial artery flow-mediated dilation (FMD) and reactive hyperemia] and cerebral vasodilator function (cerebral vasomotor reactivity to hypercapnia; CVMR) and increased central arterial stiffness. Sixteen young adults who were at least 4 wk past a COVID-19 diagnosis and 12 controls who never had COVID-19 were studied. Eight subjects with COVID-19 were symptomatic (SYM) and eight were asymptomatic (ASYM) at the time of testing. FMD and reactive hyperemia were not different between COVID and control groups. However, FMD was lower in SYM (3.8 ± 0.6%) compared with ASYM (6.8 ± 0.9%; P = 0.007) and control (6.8 ± 0.6%; P = 0.003) with no difference between ASYM and control. Similarly, peak blood velocity following cuff release was lower in SYM (47 ± 8 cm/s) compared with ASYM (64 ± 19 cm/s; P = 0.025) and control (61 ± 14 cm/s; P = 0.036). CVMR and arterial stiffness were not different between any groups. In summary, peripheral macrovascular and microvascular function, but not cerebral vascular function or central arterial stiffness were blunted in young adults symptomatic beyond the acute phase of COVID-19. In contrast, those who were asymptomatic had similar vascular function compared with controls who never had COVID-19.NEW & NOTEWORTHY This study was the first to investigate the persistent effects of COVID-19 on vascular function in otherwise healthy young adults. We demonstrated that peripheral macrovascular and microvascular vasodilation was significantly blunted in young adults still symptomatic from COVID-19 beyond the acute phase (>4 wk from diagnosis), whereas those who become asymptomatic have similar vascular function compared with controls who never had COVID-19. In contrast, cerebral vascular function and central arterial stiffness were unaffected irrespective of COVID-19 symptomology.


Subject(s)
COVID-19/complications , Cerebrovascular Circulation , Regional Blood Flow , Vasodilation , Adult , Blood Flow Velocity , COVID-19/diagnosis , COVID-19/physiopathology , Female , Humans , Male , Vascular Stiffness
8.
Urol Int ; 105(9-10): 916-919, 2021.
Article in English | MEDLINE | ID: covidwho-1262425

ABSTRACT

Infection by COVID-19, being a respiratory disease caused by SARS-CoV-2, can predispose to arterial and venous thrombotic disease, in response to excessive inflammation, platelet activation, endothelial dysfunction, and venous stasis. During the COVID-19 pandemic period, the technological and resource availability for the care of these patients with thrombotic disease is critical, marking a factor of morbidity and poor prognosis in these cases. We describe a case of priapism in a patient with COVID-19, during the course of systemic inflammatory response syndrome and respiratory distress syndrome with a procoagulant state, seeking to relate the pathophysiological factors of ischemic priapism in patients with infection with SARS-Cov-2.


Subject(s)
COVID-19/complications , Ischemia/etiology , Penile Erection , Penis/blood supply , Priapism/etiology , Adult , COVID-19/diagnosis , COVID-19/virology , Fatal Outcome , Humans , Ischemia/diagnosis , Ischemia/physiopathology , Male , Priapism/diagnosis , Priapism/physiopathology , Regional Blood Flow
9.
Microvasc Res ; 138: 104196, 2021 11.
Article in English | MEDLINE | ID: covidwho-1258467

ABSTRACT

OBJECTIVES: The hyperinflammatory state and the viral invasion may result in endothelial dysfunction in SARS-CoV-2 infection. Although a method foreseeing microvascular dysfunction has not been defined yet, studies conducted in patients diagnosed with COVID-19 have demonstrated the presence of endotheliitis. With this study, we aimed to investigate the microvascular circulation in patients diagnosed with COVID-19 and multisystem inflammatory syndrome in children (MIS-C) by nailfold videocapillaroscopy (NVC). METHODS: Thirty-one patients with SARS-CoV-2 infection, 25 of whom were diagnosed with COVID-19 and 6 with MIS-C and 58 healthy peers were included in the study. NVC was performed in eight fingers with 2 images per finger and 16 images were examined for the morphology of capillaries, presence of pericapillary edema, microhemorrhage, avascular area, and neoangiogenesis. Capillary length, capillary width, apical loop, arterial and venous width, and intercapillary distance were measured from three consecutive capillaries from the ring finger of the non-dominant hand. RESULTS: COVID-19 patients showed significantly more capillary ramification (p < 0.001), capillary meandering (p = 0.04), microhemorrhage (p < 0.001), neoangiogenesis (p < 0.001), capillary tortuosity (p = 0.003). Capillary density (p = 0.002) and capillary length (p = 0.002) were significantly lower in the patient group while intercapillary distance (p = 0.01) was significantly longer compared with healthy volunteers. Morphologically, patients with MIS-C had a higher frequency of capillary ramification and neoangiogenesis compared with COVID-19 patients (p = 0.04). CONCLUSION: Abnormal capillary alterations seen in COVID-19 and MIS-C patients indicate both similar and different aspects of these two spectra of SARS-CoV-2 infection and NVC appears to be a simple and non-invasive method for evaluation of microvascular involvement.


Subject(s)
COVID-19/pathology , Capillaries/pathology , Microscopic Angioscopy , Nails/blood supply , Systemic Inflammatory Response Syndrome/pathology , Adolescent , Age Factors , Biomarkers/blood , C-Reactive Protein/analysis , COVID-19/physiopathology , COVID-19/virology , Capillaries/physiopathology , Case-Control Studies , Child , Child, Preschool , Female , Fibrin Fibrinogen Degradation Products/analysis , Humans , Male , Microcirculation , Predictive Value of Tests , Regional Blood Flow , Systemic Inflammatory Response Syndrome/physiopathology , Systemic Inflammatory Response Syndrome/virology
10.
Respir Med ; 185: 106469, 2021.
Article in English | MEDLINE | ID: covidwho-1240603

ABSTRACT

BACKGROUND: The prothrombotic phenotype and diffuse intravascular coagulation observed in COVID-19 reflect endothelial dysfunction, which is linked to blood flow delivery deficiencies and cardiovascular risk. Assessments of detect vascular deficiencies among newly diagnosed and hospitalized patients due to COVID-19 have yet to be determined. OBJECTIVE: To assess endothelial function characteristics in relation to length of hospitalization and mortality in patients diagnosed with COVID-19 and compare to patients without COVID-19. METHODS: A prospective observational study involving 180 patients with confirmed COVID-19 (COVID-19 group) or suspected and ruled out COVID-19 (Non-COVID-19 group). Clinical evaluation and flow mediated vasodilation (FMD) were performed between the first 24-48 h of hospitalization. Patients were followed until death or discharge. RESULTS: We evaluated 98 patients (COVID-19 group) and 82 (Non-COVID-19 group), COVID-19 group remained hospitalized longer and more deaths occurred compared to the Non-COVID-19 group (p = 0.01; and p < 0.01). Patients in COVID-19 group also had a significantly greater reduction in both FMDmm and FMD% (p < 0.01 in both). We found that absolute FMD≤0.26 mm and relative FMD≤3.43% were the ideal cutoff point to predict mortality and longer hospital stay. In Kaplan Meyer's analysis patients had a high probability of death within a period of up to 10 days of hospitalization. CONCLUSION: Patients hospitalized for COVID-19 present endothelial vascular dysfunction early, remained hospitalized longer and had a higher number of deaths, when compared with patients without COVID-19.


Subject(s)
Brachial Artery/physiopathology , COVID-19/epidemiology , Cardiovascular Diseases/physiopathology , Endothelium, Vascular/physiopathology , Regional Blood Flow/physiology , Vasodilation/physiology , Cardiovascular Diseases/epidemiology , Comorbidity , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prospective Studies , SARS-CoV-2 , United States/epidemiology
11.
Shock ; 56(6): 964-968, 2021 12 01.
Article in English | MEDLINE | ID: covidwho-1220083

ABSTRACT

BACKGROUND: Endothelial and microvascular dysfunction may be a key pathogenic feature of severe COVID-19. The aim of this study was to investigate endothelial-dependent and endothelial-independent skin microvascular reactivity in patients with critical COVID-19. METHODS: Twelve patients with COVID-19 treated with non-invasive or invasive mechanical ventilation were included in the study. We investigated skin microvascular reactivity on 2 separate days during hospitalization (study day 1 and 2) and at least 3 months after disease onset (study day 3). Twelve controls with no confirmed or suspected COVID-19 infection during 2020 were also examined. Skin perfusion was investigated through Laser Speckle Contrast Imaging before and after iontophoresis of acetylcholine (ACh) and sodium nitroprusside (SNP) to determine the endothelial-dependent and the endothelial-independent vasodilation, respectively. RESULTS: Compared to controls, patients with critical COVID-19 had higher basal skin perfusion and reduced responses to endothelial-dependent (ACh, P = 0.002) and endothelial-independent (SNP, P = 0.01) vasodilator drugs on study day 1. In addition, the ACh/SNP ratio was significantly reduced in patients (0.50 ±â€Š0.36 vs. 0.91 ±â€Š0.49 in controls, P = 0.02). Three months after disease onset, surviving patients tended to have reduced ACh-mediated vasodilation compared to controls (P = 0.08). CONCLUSIONS: This small-sized pilot study demonstrates that critical COVID-19 infection is associated with microvascular impairment and, in particular, a markedly reduced endothelial function. Our results also suggest that microvascular function may not be fully recovered 3 months after disease onset.


Subject(s)
COVID-19/epidemiology , Critical Illness/epidemiology , Endothelium, Vascular/physiopathology , Microcirculation/physiology , Regional Blood Flow/physiology , Vasodilation/physiology , Aged , COVID-19/physiopathology , Comorbidity , Female , Follow-Up Studies , Humans , Male , Microvessels/physiopathology , Middle Aged , Pilot Projects , Prospective Studies , SARS-CoV-2
12.
J Appl Physiol (1985) ; 129(6): 1413-1421, 2020 12 01.
Article in English | MEDLINE | ID: covidwho-1064196

ABSTRACT

The transport of oxygen between blood and tissue is limited by blood's capillary transit time, understood as the time available for diffusion exchange before blood returns to the heart. If all capillaries contribute equally to tissue oxygenation at all times, this physical limitation would render vasodilation and increased blood flow insufficient means to meet increased metabolic demands in the heart, muscle, and other organs. In 1920, Danish physiologist August Krogh was awarded the Nobel Prize in Physiology or Medicine for his mathematical and quantitative, experimental demonstration of a solution to this conceptual problem: capillary recruitment, the active opening of previously closed capillaries to meet metabolic demands. Today, capillary recruitment is still mentioned in textbooks. When we suspect symptoms might represent hypoxia of a vascular origin, however, we search for relevant, flow-limiting conditions in our patients and rarely ascribe hypoxia or hypoxemia to short capillary transit times. This review describes how natural changes in capillary transit-time heterogeneity (CTH) and capillary hematocrit (HCT) across open capillaries during blood flow increases can account for a match of oxygen availability to metabolic demands in normal tissue. CTH and HCT depend on a number of factors: on blood properties, including plasma viscosity, the number, size, and deformability of blood cells, and blood cell interactions with capillary endothelium; on anatomical factors including glycocalyx, endothelial cells, basement membrane, and pericytes that affect the capillary diameter; and on any external compression. The review describes how risk factor- and disease-related changes in CTH and HCT interfere with flow-metabolism coupling and tissue oxygenation and discusses whether such capillary dysfunction contributes to vascular disease pathology.


Subject(s)
Capillaries/physiology , Microcirculation , Models, Cardiovascular , Oxygen Consumption , Oxygen/blood , Alzheimer Disease/blood , Alzheimer Disease/physiopathology , Anemia, Sickle Cell/blood , Anemia, Sickle Cell/physiopathology , Animals , Blood Flow Velocity , Cardiovascular Diseases/blood , Cardiovascular Diseases/physiopathology , Diffusion , Humans , Hypoxia/blood , Hypoxia/physiopathology , Regional Blood Flow , Time Factors
14.
Shock ; 55(4): 479-487, 2021 04 01.
Article in English | MEDLINE | ID: covidwho-744652

ABSTRACT

BACKGROUND: Acute kidney injury (AKI) is a common complication of COVID-19 critical illness but the pathophysiology is uncertain. Some evidence has indicated that a vascular aetiology may be implicated. We used contrast-enhanced ultrasound (CEUS) and echocardiography to study renal perfusion and global blood flow and compared our findings with measurements taken in a group of septic shock patients and healthy volunteers. METHODS: Prospective case-control study. Renal perfusion variables were assessed with CEUS; macrovascular blood flow was assessed using Doppler analysis of large renal vessels; echocardiography was used to assess right and left heart function and cardiac output. RESULTS: CEUS-derived parameters were reduced in COVID-19 associated AKI compared with healthy controls (perfusion index 3,415 vs. 548 a.u., P = 0·001; renal blood volume 7,794 vs. 3,338 a.u., P = 0·04). Renal arterial flow quantified using time averaged peak velocity was also reduced compared with healthy controls (36·6 cm/s vs. 20·9 cm/s, P = 0.004) despite cardiac index being similar between groups (2.8 L/min/m2 vs. 3.7 L/min/m2, P = 0.07). There were no differences in CEUS-derived or cardiac parameters between COVID-19 and septic shock patients but patients with septic shock had more heterogeneous perfusion variables. CONCLUSION: Both large and small vessel blood flow is reduced in patients with COVID-19 associated AKI compared with healthy controls, which does not appear to be a consequence of right or left heart dysfunction. A reno-vascular pathogenesis of COVID-19 AKI seems likely.


Subject(s)
Acute Kidney Injury/physiopathology , COVID-19/complications , COVID-19/physiopathology , Critical Illness , Heart Function Tests , Renal Circulation/physiology , Ultrasonography , Acute Kidney Injury/diagnostic imaging , Aged , COVID-19/diagnostic imaging , Case-Control Studies , Contrast Media , Female , Humans , Male , Middle Aged , Prospective Studies , Regional Blood Flow/physiology , Shock, Septic/complications , Shock, Septic/physiopathology
15.
J Thromb Thrombolysis ; 50(4): 790-794, 2020 Nov.
Article in English | MEDLINE | ID: covidwho-713251

ABSTRACT

Several autopsy studies showed microthrombi in pulmonary circulation of severe COVID-19 patients. The major limitation of these investigations is that the autopsy provided static information. Some of these alterations could be secondary to the disseminated intravascular coagulation (DIC) observed as the final standard route to the multisystem organ failure exhibited in critically ill patients. We report preliminary results of an in vivo evaluation of sublingual microcirculation in thirteen patients with severe COVID-19 requiring mechanical ventilation. We observed multiple filling defects moving within the microvessels indicative of thrombi in most of the cases 11/13 (85%). This is the first imaging documentation of microvascular thrombosis in living severe COVID-19 patients since the beginning of the hospitalization. The clinical relevance of microvascular thrombosis in this disease requires further research.


Subject(s)
Blood Coagulation , Coronavirus Infections/complications , Microcirculation , Mouth Floor/blood supply , Pneumonia, Viral/complications , Thrombosis/physiopathology , Aged , Betacoronavirus/pathogenicity , COVID-19 , Coronavirus Infections/therapy , Coronavirus Infections/virology , Female , Host-Pathogen Interactions , Humans , Male , Middle Aged , Pandemics , Pneumonia, Viral/therapy , Pneumonia, Viral/virology , Regional Blood Flow , Respiration, Artificial , SARS-CoV-2 , Severity of Illness Index , Thrombosis/blood , Thrombosis/diagnostic imaging , Thrombosis/virology
16.
J Clin Monit Comput ; 35(3): 661-662, 2021 May.
Article in English | MEDLINE | ID: covidwho-649924

ABSTRACT

OBJECTIVE: Objective of this case report is to draw attention to a less known thrombotic complication associated with COVID-19, i.e., thrombosis of both radial arteries, with possible (long-term) consequences. THE CASE: In our COVID-19 ICU a 49-year-old male patient was admitted, with past medical history of obesity, smoking and diabetes, but no reported atherosclerotic complications. The patient had been admitted with severe hypoxemia and multiple pulmonary emboli were CT-confirmed. ICU-treatment included mechanical ventilation and therapeutic anticoagulation. Preparing the insertion of a new radial artery catheter for invasive blood pressure measurement and blood sampling, we detected that both radial arteries were non-pulsating and occluded: (a) Sonography showed the typical anatomical localization of both radial and ulnar arteries. However, Doppler-derived flow-signals could only be obtained from the ulnar arteries. (b) To test collateral arterial supply of the hand, a pulse-oximeter was placed on the index finger. Thereafter, the ulnar artery at the wrist was compressed. This compression caused an immediate loss of the finger's pulse-oximetry perfusion signal. The effect was reversible upon release of the ulnar artery. (c) To test for collateral perfusion undetectable by pulse-oximetry, we measured regional oxygen saturation (rSO2) of the thenar muscle by near-infrared spectroscopy (NIRS). Confirming our findings above, ulnar arterial compression demonstrated that thenar rSO2 was dependent on ulnar artery flow. The described development of bilateral radial artery occlusion in a relatively young and therapeutically anticoagulated patient with no history of atherosclerosis was unexpected. CONCLUSIONS: Since COVID-19 patients are at increased risk for arterial occlusion, it appears advisable to meticulously check for adequacy of collateral (hand-) perfusion, avoiding the harm of hand ischemia if interventions (e.g., catheterizations) at the radial or ulnar artery are intended.


Subject(s)
Arterial Occlusive Diseases/diagnostic imaging , Arterial Occlusive Diseases/etiology , COVID-19/complications , Radial Artery , SARS-CoV-2 , Arterial Occlusive Diseases/physiopathology , COVID-19/diagnostic imaging , COVID-19/physiopathology , Hand/blood supply , Hand/diagnostic imaging , Humans , Male , Middle Aged , Muscle, Skeletal/blood supply , Muscle, Skeletal/metabolism , Netherlands , Oximetry , Oxygen Consumption , Pandemics , Radial Artery/diagnostic imaging , Radial Artery/physiopathology , Regional Blood Flow , Spectroscopy, Near-Infrared , Ulnar Artery/diagnostic imaging , Ultrasonography, Doppler
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