Abraham E Wei1, Mikhail Y Maslov2, Matthew J Pezone1, Elazer R Edelman3, Mark A Lovich1. 1. Department of Anesthesiology and Pain Medicine, Steward St. Elizabeth's Medical Center/Tufts University School of Medicine, Boston, MA, 02135, USA. 2. Department of Anesthesiology and Pain Medicine, Steward St. Elizabeth's Medical Center/Tufts University School of Medicine, Boston, MA, 02135, USA. Electronic address: mikhail.maslov@steward.org. 3. Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
Abstract
BACKGROUND: Most applications of pressure-volume conductance catheter measurements assess cardiovascular function at a single point in time after genetic, pharmacologic, infectious, nutritional, or toxicologic manipulation. Use of these catheters as a continuous monitor, however, is fraught with complexities and limitations. METHODS: Examples of the limitations and optimal use of conductance catheters as a continuous, real-time monitor of cardiovascular function are demonstrated during inotropic drug infusion in anesthetised rats. RESULTS: Inotropic drug infusion may alter ventricular dimensions causing relative movement of a well-positioned catheter, generating artifacts, including an abrupt pressure rise at end-systole that leads to over estimation of indices of contractility (max dP/dt) and loss of stroke volume signal. Simple rotation of the catheter, echocardiography-guided placement to the centre of the ventricle, or ventricular expansion through crystalloid infusion may correct for these artifacts. Fluid administration, however, alters left ventricular end-diastolic pressure and volume and therefore stroke volume, thereby obscuring continuous real-time haemodynamic measurements. CONCLUSIONS: Pressure-volume artifacts during inotropic infusion are caused by physical contact of the catheter with endocardium. Repeated correction of catheter position may be required to use pressure volume catheters as a continuous real-time monitor during manipulations that alter ventricular dimensions, such as inotropic therapy.
BACKGROUND: Most applications of pressure-volume conductance catheter measurements assess cardiovascular function at a single point in time after genetic, pharmacologic, infectious, nutritional, or toxicologic manipulation. Use of these catheters as a continuous monitor, however, is fraught with complexities and limitations. METHODS: Examples of the limitations and optimal use of conductance catheters as a continuous, real-time monitor of cardiovascular function are demonstrated during inotropic drug infusion in anesthetised rats. RESULTS: Inotropic drug infusion may alter ventricular dimensions causing relative movement of a well-positioned catheter, generating artifacts, including an abrupt pressure rise at end-systole that leads to over estimation of indices of contractility (max dP/dt) and loss of stroke volume signal. Simple rotation of the catheter, echocardiography-guided placement to the centre of the ventricle, or ventricular expansion through crystalloid infusion may correct for these artifacts. Fluid administration, however, alters left ventricular end-diastolic pressure and volume and therefore stroke volume, thereby obscuring continuous real-time haemodynamic measurements. CONCLUSIONS: Pressure-volume artifacts during inotropic infusion are caused by physical contact of the catheter with endocardium. Repeated correction of catheter position may be required to use pressure volume catheters as a continuous real-time monitor during manipulations that alter ventricular dimensions, such as inotropic therapy.
Authors: Mikhail Y Maslov; Elazer R Edelman; Abraham E Wei; Matthew J Pezone; Mark A Lovich Journal: J Control Release Date: 2013-07-18 Impact factor: 9.776
Authors: Julie Wallis; Craig A Lygate; Alexandra Fischer; Michiel ten Hove; Jürgen E Schneider; Liam Sebag-Montefiore; Dana Dawson; Karen Hulbert; Wen Zhang; Mei Hua Zhang; Hugh Watkins; Kieran Clarke; Stefan Neubauer Journal: Circulation Date: 2005-11-15 Impact factor: 29.690