Integrated Evaluation of Hemodynamics

Welcome to the home page for our Integrated Evaluation of Hemodynamics program at the University of Manitoba.  This program began in Winnipeg, Manitoba, Canada in 2014 and has been growing ever since.

What is considered normal hemodynamics?

Intact or normal hemodynamics implies blood flow that provides adequate oxygen and nutrient delivery to the tissues1. Blood flow varies with vascular resistance and cardiac function; both may be reflected in blood pressure2. Normal cardiovascular dynamics should be considered within the context of global hemodynamic function, with the aim of achieving normal oxygen delivery and end organ performance3. The current routine assessment of hemodynamics in sick preterm and term infants is based on incomplete information. We have addressed this by adopting an approach utilizing objective techniques, namely integrating targeted neonatal echocardiography (TNE) with near-infrared spectroscopy (NIRS). Implementation of these techniques requires an individual with the requisite TNE training, preferably in an accredited program, who also has a good understanding of perinatal and neonatal cardiovascular, respiratory, and other specific end organ physiology.

Why are premature infants more susceptible  to cardiovascular compromise? 

Hemodynamic compromise in the early neonatal period is common and may lead to unfavorable neurodevelopmental outcome4. A thorough understanding of the physiology of the cardiovascular system in the preterm infants, influence of antenatal factors, and postnatal adaptation is essential for the management of these infants during the early critical phase5. The impact of the various ventilator modes, the presence of a patent ductus arteriosus (PDA), and systemic inflammation all may affect the hemodynamics6. The poor clinical indicators of systemic perfusion and the relative insensitivity of conventional echocardiographic techniques in assessing myocardial contractility mean that monitoring of the hemodynamics of the preterm infant remains a challenge7.

What is integrated hemodynamics in neonatal care?

Integrated hemodynamics focuses on how to interpret multiple tools of hemodynamics evaluation in sick infants (TNE, clinical details, NIRS, organ specific ultrasound) and the art of formulating a pathophysiologic relevant medical recommendation.

Main objectives of applying Targeted Neonatal Echocardiography and Evaluation of Neonatal hemodynamics

  • Optimise care of infants with hemodynamic compromise to prevent progression into late irreversible stages of shock (Hypoxia)
  • Decrease overall PDA related complications (Hypoxemia and hypoxia)
  • Optimize care of infants with hypoxemic respiratory failure (HRF)
  • Decrease the incidence of progression of infants with hypoxemic respiratory failure and shock to end organ dysfunction

Objective of the program

  • Orientation to the hemodynamics concepts and basics
  • Orientation to the 3 level of the pathophysiologic approach to hemodynamics:

Level one: Relying on blood pressure trends (systole, diastole, and pulse pressure) and waveforms with other clinical parameters (all NICU practitioners)

Level one plus (advanced monitoring): Relying on blood pressure trend and near infrared spectroscopy (NIRS) for assessment of hemodynamics and oxygen extraction (optional to NICU practitioners)

Level two (TNE approach): Relying on both clinical parameters and TNE for objective assessment of cardiac output, extra and intra cardiac shunts, systemic and pulmonary vascular resistance. (Neonatologist trained on TNE)

Level three (integrated evaluation of hemodynamics): integrating blood pressure trends, TNE and NIRS for assessment of oxygen delivery, specific end organ oxygen consumption and the degree of compensation (comprehensive hemodynamic approach)

  • Understanding the rationale for the measurements and the specific values for each disease, and recognize limitations of the 3 models

To see research that we have done in the area of Integrated Hemodynamics please see our publication list that can be found here.

To access our video series providing examples of TNE and presentations on the use of hemodynamics in clinical application please see our Youtube channel playlist “Integrated Neonatal Hemodynamics”

References   

  1. Wolff CB. Normal cardiac output, oxygen delivery and oxygen extraction. Adv Exp Med Biol. 2008;599:169-182. doi:10.1007/978-0-387-71764-7-23.
  2. Azhan A, Wong FY. Challenges in understanding the impact of blood pressure management on cerebral oxygenation in the preterm brain. Front Physiol. 2012;3 DEC(December):1-8. doi:10.3389/fphys.2012.00471.
  3. de Boode WP. Clinical monitoring of systemic hemodynamics in critically ill newborns. Early Hum Dev. 2010;86(3):137-141. doi:10.1016/j.earlhumdev.2010.01.031.
  4. Sehgal A. Haemodynamically unstable preterm infant: an unresolved management conundrum. Eur J Pediatr. 2011;170(10):1237-1245. doi:10.1007/s00431-011-1435-4.
  5. Vutskits L. Cerebral blood flow in the neonate. Paediatr Anaesth. 2014;24(2):22-29. doi:10.1111/pan.12307.
  6. Noori S, Stavroudis T a, Seri I. Systemic and cerebral hemodynamics during the transitional period after premature birth. Clin Perinatol. 2009;36(4):723-36, v. doi:10.1016/j.clp.2009.07.015.
  7. Elsayed YN, Amer R, Seshia MM. The impact of integrated evaluation of hemodynamics using targeted neonatal echocardiography with indices of tissue oxygenation: a new approach. J Perinatol. 2017. doi:10.1038/jp.2016.257.