HARD DECISIONS IN INTENSIVE CARE UNIT

Intensivecareunitkapak

HEMODYNAMIC MONITORING

Hülya Özden Terzi

Ankara Bilkent City Hospital, Department of Intensive Care, Ankara, Türkiye

Terzi HÖ. Hemodynamic Monitoring. In: Turan S, editor. Hard Decisions in Intensive Care Unit. 1st ed. Ankara: Türkiye Klinikleri; 2025. p.379-393.

ABSTRACT

Hemodynamic monitoring is a critical tool in the management of critically ill patients, providing real-time data that guides clinical decision-making and helps optimize tissue perfusion. By evaluating parameters such as blood pressure, cardiac output, vascular resistance, and fluid status, healthcare providers can detect early signs of complications like shock, heart failure, or hypovolemia, and tailor interventions to individual patient needs. Hemodynamic monitoring is particularly valuable in guiding fluid resuscitation and the use of vasoactive medications, ensuring that patients receive the appropriate level of care without the risks of underor over-resuscitation.

Technological advancements have expanded the range of monitoring techniques, shifting from invasive methods like pulmonary artery catheterization to less invasive approaches such as transpulmonary thermodilution, pulse wave analysis and esophageal Doppler. These methods provide continuous and real-time hemodynamic data, enabling the assessment of fluid responsiveness and cardiac output. Dynamic variables like pulse pressure variation and stroke volume variation have proven superior to static variables in predicting fluid responsiveness.

Indirect measurements of perfusion and oxygen delivery, including central venous oxygen saturation, lactate levels, and the central venous-arterial carbon dioxide difference, are also valuable in assessing tissue oxygenation. Elevated lactate levels and failure to clear lactate are associated with worse outcomes, making lactate clearance a strong prognostic marker in sepsis and other critical conditions. The central venous-arterial carbon dioxide difference, which reflects the adequacy of cardiac output in clearing metabolic carbon dioxide, has gained attention as a potential marker of tissue perfusion.

Despite the benefits, each monitoring method has its limitations and risks. For example, pulmonary artery catheterization carries risks of complications during insertion, maintenance, and withdrawal, while less invasive methods may have limitations in accuracy or applicability in certain clinical conditions. The choice of monitoring technique depends on the patient’s clinical condition, the severity of the illness, and available resources.

In conclusion, hemodynamic monitoring is indispensable in critical care, enabling clinicians to make informed decisions, personalize treatment plans, and improve patient outcomes. As technology continues to evolve, the focus remains on developing less invasive, more accurate methods to assess and manage hemodynamic stability in critically ill patients.

Keywords: Hemodynamic monitoring; Critical care; Cardiac output; Fluid responsiveness; Pulse pressure variation; Lactate clearance

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