Critical ill patients are often haemodynamically unstable and accurate continuous monitoring is vital. Haemodynamic monitoring describes the measurement of the cardiovascular stability of the patient. Invasive blood pressure monitoring and central venous pressure monitoring provide a ‘real time’ measurement of the patients haemodynamic status and better allows clinicians to pre-emptively treat a patient before a more serious problem arises. Although invasive blood pressure monitoring has several advantages compared to non-invasive blood pressure monitoring, it is not without risk. Central venous pressure monitoring is similarly beneficial in that it supports the clinical decision making regarding a patient’s fluid status but also comes with additional risks. This chapter explores invasive blood pressure and central venous pressure monitoring in detail.

Key Learning Points

1. 1. Ultrasound guidance can, in trained hands, improve success of venous cannulation in difficult patients.

2. 2. Different techniques exist, with none clearly superior to the other.

3. 3. Find a technique that works for you and stick with it.

4. 4. An understanding of vascular anatomy is essential to successful cannulation.

5. 5. Differentiating between arteries and veins can be done in various ways and is an essential skill.