Shock and Haemodynamic Monitoring

Abstract

Haemodynamic instability and shock are some of the most common causes of referral to critical care services and are very common in critically ill patients in ICU. In this chapter, I describe basic cardiovascular physiology and the basic pathophysiology of shock. Shock is the state of circulatory failure that leads to inadequate oxygen delivery to cells. This results in organ failure and cells switching to a predominantly anaerobic pathway of energy generation (respiration). Shock can be broadly classified into hypovolaemic, distributive, cardiogenic and obstructive shock. The type of shock can be determined by the clinical features and monitoring although this is not always easy and different types of shock can co-exist. Advanced monitors in ICU include invasive blood pressure monitoring, a variety of Cardiac Output monitors and Point of Care Ultrasound. The management of shock depends on the type of shock and can include intravenous fluids administration, inotropes, vasopressors, vasodilators, and adjunctive therapy, for example, corticosteroids. In this chapter, I also discuss practical issues that are of interest to newcomers to ICU.