Red blood cell transfusion compared with gelatin solution and no infusion after cardiac surgery: effect on microvascular perfusion, vascular density, hemoglobin, and oxygen saturation.

Background: After cardiac surgery, red blood cell (RBC) transfusion may improve systemic hemodynamics and thereby microvascular blood flow and O2 delivery (DO2).

Study Design And Methods: In a nonrandomized prospective observational study on post-cardiac surgery patients, systemic hemodynamics and microvascular blood flow, vascular density (sidestream dark-field imaging), hemoglobin (Hb) content, and saturation (reflectance spectrophotometry) were measured before and 1 hour after start of transfusion of 1 to 2 units of leukoreduced RBCs (270±203 mL), 500 mL of gelatin solution, or control (no infusion), when patients were considered clinically hypovolemic with (RBC group, n=12) or without (gelatin group, n=14) anemia (Hb<10 g/dL) or not (n=13), respectively.

Results: Systemic Hb was lower and increased in the RBC transfusion but not in gelatin and control groups.

Pulsatile flow during cardiopulmonary bypass preserves postoperative microcirculatory perfusion irrespective of systemic hemodynamics.

The onset of nonpulsatile cardiopulmonary bypass is known to deteriorate microcirculatory perfusion, but it has never been investigated whether this may be prevented by restoration of pulsatility during extracorporeal circulation. We therefore investigated the distinct effects of nonpulsatile and pulsatile flow on microcirculatory perfusion during on-pump cardiac surgery. Patients undergoing coronary artery bypass graft surgery were randomized into a nonpulsatile (n = 17) or pulsatile (n = 16) cardiopulmonary bypass group.

Cardiac displacement during off-pump coronary artery bypass grafting surgery: effect on sublingual microcirculation and cerebral oxygenation.

Cardiac displacement during off-pump coronary artery bypass (OPCAB) surgery causes a fall in cardiac output. Here, we investigate how this drop in systemic perfusion is transferred to the oxygenation of sublingual and cerebral tissue. Sublingual microcirculatory perfusion or microcirculatory hemoglobin oxygen saturation (μHbSO(2)) measurements were performed using sidestream dark-field imaging and reflectance spectrophotometry, respectively (both n = 12).

Distinct alterations in sublingual microcirculatory blood flow and hemoglobin oxygenation in on-pump and off-pump coronary artery bypass graft surgery.

Objective: The authors hypothesized that cardiopulmonary bypass (CPB) (on-pump) is associated with more severe changes in the microcirculatory blood flow and tissue oxygenation as compared with off-pump coronary artery bypass surgery.

Design: An observational study.

Setting: A university hospital and teaching hospital.

Cardiac resynchronization improves microcirculation.

Background: Although it is known that cardiac resynchronization therapy (CRT) in heart failure (HF) patients improves systemic circulation, its acute effects on microcirculation are as yet unknown. Therefore we investigated the sublingual microcirculatory changes in HF patients from CRT and right ventricular (RV) pacing by use of orthogonal polarization spectral (OPS) imaging.

Methods And Results: Twelve consecutive HF patients with a CRT device and 20 healthy individuals (HI) were included.

Endothelial glycocalyx damage coincides with microalbuminuria in type 1 diabetes.

Chronic hyperglycemia underlies microvascular complications in patients with type 1 diabetes. The mechanisms leading to these vascular complications are not fully understood. Recently, we observed that acute hyperglycemia results in endothelial glycocalyx damage.

START Trial: a pilot study on STimulation of ARTeriogenesis using subcutaneous application of granulocyte-macrophage colony-stimulating factor as a new treatment for peripheral vascular disease.

Background: Granulocyte-macrophage colony-stimulating factor (GM-CSF) was recently shown to increase collateral flow index in patients with coronary artery disease. Experimental models showed beneficial effects of GM-CSF on collateral artery growth in the peripheral circulation. Thus, in the present study, we evaluated the effects of GM-CSF in patients with peripheral artery disease.

Influence of percutaneous coronary intervention on coronary microvascular resistance index.

Background: Coronary microvascular resistance during maximal hyperemia is generally assumed to be unaffected by percutaneous coronary interventions (PCIs). We assessed a velocity-based index of hyperemic microvascular resistance (h-MR(v)) by using prototypes of a novel, dual-sensor (Doppler velocity and pressure)-equipped guidewire before and after PCI to test this hypothesis.

Methods And Results: Aortic pressure, flow velocity (h-v), and pressure (h-P(d)) distal to 24 coronary lesions were measured simultaneously during maximal hyperemia induced by intracoronary adenosine.

Design of the START-trial: STimulation of ARTeriogenesis using subcutaneous application of GM-CSF as a new treatment for peripheral vascular disease. A randomized, double-blind, placebo-controlled trial.

Peripheral arterial disease (PAD) affects a large percentage of the elderly population. Standard invasive treatment, apart from risk factor modulation, consists of bypass surgery or percutaneous transluminal angioplasty. However, symptomatic recurrence rates are high for both procedures and a substantial part of the patient population with PAD is not a candidate for invasive revascularization due to complexity of the lesion and/or co-morbidity.