The Asian swamp eel (Monopterus albus, Zuiew 1793) is a facultative air-breathing fish with reduced gills. Previous studies have shown that gas exchange seems to occur across the epithelium of the buccopharyngeal cavity, the esophagus and the integument, resulting in substantial diffusion limitations that must be compensated by adaptations in others steps of the O₂ transport system to secure adequate O₂ delivery to the respiring tissues. We therefore investigated O₂ binding properties of whole blood, stripped hemoglobin (Hb), two major isoHb components and the myoglobin (Mb) from M. albus. Whole blood was sampled using indwelling catheters for blood gas analysis and determination of O₂ equilibrium curves. Hb was purified to assess the effects of endogenous allosteric effectors, and Mb was isolated from heart and skeletal muscle to determine its O₂ binding properties. The blood of M. albus has a high O₂ carrying capacity [hematocrit (Hct) of 42.4±4.5%] and binds O₂ with an unusually high affinity (P₅₀=2.8±0.4mmHg at 27°C and pH7.7), correlating with insensitivity of the Hb to the anionic allosteric effectors that normally decrease Hb-O₂ affinity. In addition, Mb is present at high concentrations in both heart and muscle (5.16±0.99 and 1.08±0.19mg ∙ g wet tissue⁻¹, respectively). We suggest that the high Hct and high blood O₂ affinity serve to overcome the low diffusion capacity in the relatively inefficient respiratory surfaces, while high Hct and Mb concentration aid in increasing the O₂ flux from the blood to the muscles.
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http://dx.doi.org/10.1016/j.cbpa.2014.08.001 | DOI Listing |
Ann Vasc Surg
October 2023
Aortic Center and Department of Vascular Surgery, Heart Vascular and Thoracic Institute, Cleveland Clinic, Cleveland, OH. Electronic address:
Background: Cardiovascular complications are a major cause of morbidity and mortality in the postoperative period after major vascular surgery. Depending on the study population, up to 25% of patients have troponin elevation after noncardiac surgery, yet many do not meet the diagnosis of myocardial infarction (MI). Although outcomes of routine troponin elevation in patients undergoing mixed major vascular surgery have been evaluated, this has not been studied exclusively in elective, open abdominal aortic aneurysm repair (oAAA), especially regarding perioperative and overall mortality.
View Article and Find Full Text PDFJ Vasc Surg
June 2023
Division of Vascular and Endovascular Surgery, University of Massachusetts Chan Medical School, Worcester, MA. Electronic address:
Objective: Although the Society for Vascular Surgery recommends repair of abdominal aortic aneurysms (AAA) at 5.5 cm or greater in men and 5.0 cm or greater in women, AAA repair below these thresholds has been well-documented.
View Article and Find Full Text PDFJ Vasc Surg
January 2023
Section of Vascular Surgery, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire.
Introduction: The Centers for Disease Control and Prevention (CDC) has deemed obesity a national epidemic and contributor to other leading causes of death including heart disease, stroke, and diabetes. Accordingly, the role of body mass index (BMI) and its impact on surgical outcomes has been a focus of persistent investigation. The purpose of this study was to quantify the effect of BMI on open abdominal aortic aneurysm repair (oAAA) outcomes in contemporary practice.
View Article and Find Full Text PDFJ Vasc Surg
February 2022
Department of Surgery, King Saud University, Riyadh, Saudi Arabia; Li Ka Shing Knowledge Institute, St. Michael's Hospital, Toronto, Ontario, Canada; Department of Surgery, University of Toronto, Toronto, Ontario, Canada; Division of Vascular Surgery, St. Michael's Hospital, Unity Health Toronto, Toronto, Ontario, Canada. Electronic address:
J Vasc Surg
January 2022
Division of Vascular and Endovascular Surgery, Brigham and Women's Hospital, Boston, Mass.
Objective: In a recent analysis, we discovered lower mortality after open abdominal aortic aneurysm repair (OAAA) in the Society for Vascular Surgery Vascular Quality Initiative (VQI) database when compared with previously published reports of other national registries. Understanding differentials in these registries is essential for their utility because such datasets increasingly inform clinical guidelines and health policy.
Methods: The VQI, American College of Surgeons National Surgical Quality Improvement Program (NSQIP), and National Inpatient Sample (NIS) databases were queried to identify patients who had undergone elective OAAA between 2013 and 2016.
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