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Hemodynamics

  • Scott A. Hagen
  • Timothy E. Corden
Chapter

Abstract

The cardiovascular system is responsible for providing adequate blood flow to meet the metabolic demands of the body and its organs. The most significant function of the cardiovascular system is the delivery of oxygen to meet the demand for cellular oxygen consumption. Although increases in oxygen delivery can occur over time through an increase in hemoglobin concentration, during an acute illness the primary physiologic response to an increase in oxygen demand is an increase in cardiac output. If cardiac output is not sufficient to meet the metabolic needs of the body as a whole, a redistribution of regional blood flow must occur to maintain adequate oxygen delivery to vital organs. The cardiovascular system of an otherwise healthy child with acute illness will typically perform this function well, but in the critically ill child with progressive disease, the physiologic response to an increasing oxygen demand may be inadequate and unable to meet the metabolic demands of the body. Caring for the child with critical illness requires intervention by the intensivist to balance oxygen delivery and consumption. In some cases, therapeutic interventions to support one system, such as positive pressure mechanical ventilation to support breathing, may have undesirable effects on the cardiovascular system. When caring for the critically ill child, it is important to have a fundamental understanding of normal cardiac physiology, cardiopulmonary interactions, and how critical illness and therapeutic interventions can alter cardiac function. This chapter will review the physiology and function of the heart, and how critical illness alters cardiovascular physiology. In addition, the unique interactions that occur between the heart and lungs will be discussed in both the healthy and ill child.

Keywords

Venous Return Systolic Pressure Variation Negative Intrathoracic Pressure Intravascular Volume Status Systemic Venous Return 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag London Limited 2012

Authors and Affiliations

  1. 1.Pediatric Critical Care Medicine, Department of PediatricsUniversity of Wisconsin School of Medicine and Public Health, American Family Children’s HospitalMadisonUSA
  2. 2.Pediatric Critical Care Medicine, Department of Pediatrics, Injury Research CenterMedical College of Wisconsin, Children’s Hospital of WisconsinMilwaukeeUSA

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