Transpulmonary Thermodilution Using an Implented Central Venous Access Port

Perioperative hemodynamic optimization requires monitoring adapted to the risks of the surgery and the patient. The investigators currently use a local hemodynamic protocol based on the data of the literature. According to this protocol, specific patients may require cardiac index and central venous oxygen saturation monitoring. the investigators chose to monitor the cardiac index (CI) with the transpulmonary thermodilution technique (TPTD) (PiCCO, Pulsion Medical System, Munich, Allemagne). The technique is based on the injection of a cooled bolus of saline into a central vein with a central venous catheter (CVC). The variation of temperature is measured with an arterial femoral catheter and allows the assessment of the cardiac output according to Stewart-Hamilton's theory. Many studies showed the reliability of this technique (Bein J Cardio Thorac Vasc Anesth 2004, Buhre Cardio thorac vasc anesth 1999, Felbinger J Clin ANesth 2005, Felbinger TW J Clin Anetsh 2002, Godie O Ann Thorac Surg 1999).

In our institute, most of the patients are fitted with a port for chemotherapy or parenteral nutrition. When PiCCO monitoring is necessary, a central venous catheter is inserted on the opposite side of the permanent implantable venous port. Indeed, insertion of the CVC can be more difficult because of the port. It may be interesting to use the port for TPTD in order to avoid the insertion of a new CVC. This would be possible only if the measurement of CI by the port was as reliable as the classical measurement with a CVC.

The aim of this study was to assess whether measurement of the CI by TPTD was possible and reliable via the port. The investigators conducted a prospective study comparing the measurement of the CI by TPTD before and after fluid challenge via the port versus the CVC.