Sonographic Assessment of the Inferior Vena Cava

1. Sonographic Assessment of the Inferior Vena Cava Alexis P Langsfeld MD

2. Anatomy

3. Anatomy • The inferior vena cava returns blood from the body to the right atrium • Formed by the convergence of the illiac veins • Retroperitoneal • Right of the aorta • Normal size <2.5 cm • Varies w respiration

4. Respiratory variation • expands w/ expiration • Contracts w/ inspiration • Due to changing intrathoracic pressures.

5. IVC Anatomy

6. Technique

7. Probe Selection • Low frequency 2-5 MHz • Curvalinear probe

8. Orientation • Measure at the subcostal window • Adjacent to the rt atrium • Measure just below the diaphram - about 1 cm before the hepatic viens. • Parallel walls

9. Views • Cross section • Longitudinal

10. Venous abdominal anatomy

11. Proximal IVC

12. IVC Longitudinal

13. Aorta Thick echogenic walls Pulsatile High flow velocity Not compressable No respiratory variation IVC Thin walls Not pulsitile Low flow velocity Compressable Respiratory variation Aorta vs IVC

14. IVC & AORTA

15. Flow Velocities • Aorta = High flow velocities • IVC = lower flow velocities

16. IVC Flow

17. Aorta flow

18. Portal Vein Flow

19. Sagital IVC

20. Benefits • Assessment of volume status • Find clots • Non-invasive • No radiation • At the bedside

21. CVP Assessment

22. Gestalt method • IVC Collapse with inspiration • “YES / NO” • Yes - CVP approximately 8 • No - CVP around 15

23. Right Atrial Pressures

24. Research: ED Physicians Capable • Hruda, Jarslav et al. Echocardiographic Assessment of Preload Conditions Does Not Help at the Neonatal Intensive Care Unit. American Journal of Perinatology 2003;20:297-303. • Lloyd, TR. Accuracy of Central Venous Pressure Measurement From the Abdominal Inferior Vena Cava. Pediatrics 1992; 89: 506-508 • Krause, Irit et al. Inferior vena cava diameter: a useful method for estimation of fluid status in children on haemodialysis. Nephrology Dialysis Transplantation 2001; 16:1203-1206. • Lyon, Matthew, MD. Sonographic measurement of the inferior vena cava as a marker of blood loss. The American Journal of Emergency Medicine 2005; 23:45-50.

25. Research: CVP Assessment • Chen, Lei, Kim, Yunie, Santucci, Karen A. Use of Ultrasound Measurement of the Inferior Vena Cava Diameter as an Objective Tool in the Assessment of Children with Clinical Dehydration. Acad Emerg Med 2007 14: 841-845 • Krause, Irit et al. Inferior vena cava diameter: a useful method for estimation of fluid status in children on haemodialysis. Nephrology Dialysis Transplantation 2001; 16:1203-1206. • Lyon, Matthew, MD. Sonographic measurement of the inferior vena cava as a marker of blood loss. The American Journal of Emergency Medicine 2005; 23:45-50.

26. Conclusion • Anatomy review • Physiologic review • Technical review for good IVC measurements • Data supports use of IVC sonography as a rudimentary assessment of volume status • Can use clinically to guild patient management

27. References • Hruda, Jarslav et al. Echocardiographic Assessment of Preload Conditions Does Not Help at the Neonatal Intensive Care Unit. American Journal of Perinatology 2003;20:297-303. • Lloyd, TR. Accuracy of Central Venous Pressure Measurement From the Abdominal Inferior Vena Cava. Pediatrics 1992; 89: 506-508 • Krause, Irit et al. Inferior vena cava diameter: a useful method for estimation of fluid status in children on haemodialysis. Nephrology Dialysis Transplantation 2001; 16:1203-1206. • Lyon, Matthew, MD. Sonographic measurement of the inferior vena cava as a marker of blood loss. The American Journal of Emergency Medicine 2005; 23:45-50. • Textbook of Cardiovascular Medicine, Topol, Califf, Lippincott Williams& Wilkins 2006 • Color Duplex Sonography: Principles and Clinical Applications, Karl-Jürgen Wolf, Franz Fobbe, 2005, p.180-195 • Differential Diagnosis in Ultrasound, Gunter Schmidt, Pri, Werner, Asim Kurjak, Barbara (CON) Beuscher-Willems, - Medical - 2006