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Hypoxic Pulmonary Vasoconstriction Otterbein University Digital Commons @ Otterbein Nursing Student Class Projects (Formerly MSN) Student Research & Creative Work Summer 7-30-2016 Hypoxic Pulmonary Vasoconstriction Miranda Shull Otterbein University, [email protected] Follow this and additional works at: https://digitalcommons.otterbein.edu/stu_msn Part of the Critical Care Nursing Commons Recommended Citation Shull, Miranda, "Hypoxic Pulmonary Vasoconstriction" (2016). Nursing Student Class Projects (Formerly MSN). 200. https://digitalcommons.otterbein.edu/stu_msn/200 This Project is brought to you for free and open access by the Student Research & Creative Work at Digital Commons @ Otterbein. It has been accepted for inclusion in Nursing Student Class Projects (Formerly MSN) by an authorized administrator of Digital Commons @ Otterbein. For more information, please contact [email protected]. Hypoxic Pulmonary Vasoconstriction Miranda Shull RN BSN CCRN Otterbein University, Westerville, Ohio Characteristics & Additional Sources Introduction Symptoms Pathophysiology Archer, S., & Michelakis, E. (2002). The • The result of only one portion • HPV is the autoregulatory • Hypoxic pulmonary Mechanism(s) of Hypoxic Pulmonary of the lung being affected, is mechanism which prevents the vasoconstriction (HPV) is Vasoconstriction: Potassium that blood is shunted from the ventilation to perfusion mismatch characterized by a local reaction to Channels, Redox O2 Sensors, and hypoxic region to the well caused by alveolar hypoxia in order hypoxic areas of the lung. Controversies. Physiology, 17(4), ventilated portion of the lung to improve gas exchange and • HPV is a reflexive contraction of 131-137. (Artusio & Yao, 2012). arterial oxygenation. vascular smooth muscle in the doi:10.1152/nips.01388.2002 • If the entire lung is affected by • HPV is active in utero, reducing pulmonary circulation. This Ariyaratnam, P., Loubani, M., & Morice, alveolar hypoxia however, then pulmonary blood flow, the ability to reflexive contraction is in response A. H. (2013). Hypoxic Pulmonary there is widespread pulmonary do so carries into adulthood, to low partial pressure of oxygen Vasoconstriction in Humans. BioMed vasoconstriction, leading to allowing for matching of ventilation (Lumb & Slinger, 2015). Research International, 2(2), 1-8. pulmonary hypertension to perfusion in the presence of • This vasoconstriction seen in the Joyner, M. J., & Johnson, B. D. (2008). (Artusio & Yao, 2012). alveolar hypoxia (Dospinescu, vasculature of the pulmonary Iron lung? New ideas about hypoxic • The symptoms of HPV depend 2009). system is the major difference pulmonary vasoconstriction. The of the degree of hypoxic lung • The cellular mechanism involves a which separates it from the Journal of Physiology, 586(24), 5837- tissue. redox-based oxygen sensor in the systemic circulation, which usually 5838.doi:10.1113/jphysiol.2008.166 • HPV is a ocal reaction occurring smooth muscle cells of the vasodilates in response to hypoxia 249 in hypoxic areas of the lung. pulmonary arteries. Hypoxia then (Lumb & Slinger, 2015). Morgan, G. E., Mikhail, M. S., & Murray, • It may be localized due to reduces production of activated • My intent of this research project is M. J. (2006). Clinical anesthesiology. various causes including oxygen species and they act as to explain the pathophysiological New York: Lange Medical regional atelectasis. It can also second messengers from the process of HPV and understand the Retrieved from http://www.derangedphysiology.com/main/required-reading/respiratory-medicine-and- Books/McGraw Hill, Medical Pub. be diffuse, affecting both lungs, oxygen sensors. Outflow is then implications of anesthesia related ventilation/Chapter%205.1.5/inhaled-and-systemic-pulmonary-vasodilators-ards Division. as seen in high altitude reduced leading to inhibition of to it. Waypa, G. B., & Schumacker, P. T. (2007). pulmonary edema. voltage dependent potassium • Through this research I will be able Oxygen sensing in hypoxic • HPV is triggered by alveolar channels further resulting in an to provide a safe and personalized pulmonary vasoconstriction: Using hypoxia, not arterial hypoxemia influx of extracellular calcium plan of care for my patients, while new tools to answer an age-old as one may assume. which causes vasoconstriction taking into account the risks of question. Experimental Physiology, • The peak effect of alveolar (Nagelhout & Plaus, 2014). HPV. Factors that Reduce Anesthetic Implications References 93(1), 133-138. hypoxia is seen within 15 • If the alveolar hypoxia persists it Yoo, H. Y., Park, S. J., Kim, H. J., Kim, W. K., minutes. can lead to permanent pulmonary & Kim, S. J. (2014). Integrative • Many elements can affect HPV hypertension, which will eventually Effectiveness of HPV • During mechanical ventilation it is understanding of hypoxic pulmonary including cardiac output, lead to cor pulmonale (Artusio & Artusio, J. F., & Yao, F. F. (2008). Yao & very important to match ventilation vasoconstriction using in vitro medications, PH and Pco2. Yao, 2012). Arturio's anesthesiology: Problem- • Alkalosis and perfusion in order to optimize models: From ventilated/perfused oriented patient management. • Hypothermia gas exchange in the mechanically lung to single arterial myocyte. Philadelphia, PA: Lippincott. • Hypocapnia ventilated patient. Integrative Medicine Research, 3(4), Dospinescu, C. (2009). Cellular • Excessive tidal volume • Studies have shown that an 180-188. mechanisms of acute hypoxic • Excessive PEEP occlusion of the airway can very pulmonary vasoconstriction in • Vasodilators quickly lead to a reduction of blood intrapulmonary veins (Doctoral • Calcium channel blockers flow to that region of the lung by dissertation). Retrieved from Ebsco • Phosphodiesterase inhibitors about 50% (Lumb & Slinger, 2015). Host (edsble.513553) • Hypervolemia • In both asthma and chronic Lumb, A. B., & Slinger, P. (2015). obstructive pulmonary disease Hypoxic Pulmonary (COPD), giving 100% oxygen Vasoconstriction. Anesthesiology, worsens the ventilation to perfusion 122(4), 932-946. (V/Q) matching ratio. Nagelhout, J. J., & Plaus, K. L. (2014). • Many of the drugs used during Nurse anesthesia. St. Louis, MO: anesthesia have some sort of effect Elsevier/Saunders. on HPV. Many anesthetic drugs inhibit HPV, however, none commonly used augment it (Lumb & Sllinger, 2015). • Any drug that is a vasodilator may inhibit HPV, and all current anesthetic agents can inhibit HPV but are dose dependent (Lumb & Slinger, 2015). • The effects of nitrous oxide on HPV How hypoxic pulmonary vasoconstriction works, retrieved from http://www.jonathandownham.com/hypoxic-drive/ are unclear a this time. .
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