Hemodynamic waveform detection from pulmonary artery catheters in the ICU

We systematically evaluated whether routine pulmonary artery catheterizatio n and the standard recording systems used in the ICU allowed physicians to detect right atrial pressure (RAP) and pulmonary artery wedge pressure (PAW P) waveform components. Fifty-seven patients requiring pulmonary artery cat heterization were studied. Standard 7.5 French (Fr), VIP(TM) (venous infusi on port) Swan-Ganz(R) pulmonary artery catheters (PAC) were used in all pat ients along with standard pressure tubing, transducers, and either of two t ypes of Hewlett-Packard strip-chart recording systems for simultaneous ECG and PAC waveform recording. The waveforms were later analyzed by four inves tigators, blinded to diagnosis, who formed a consensus. In the RAP waveform recording, a, c, and v waves were detected in 80%, 28%, and 50% of the pat ients, respectively. In the PAWP waveform recording, a and v waves were det ected in 44% and 28% of the patients, respectively. The data were analyzed to determine whether the ability to detect waveform components was associat ed with cardiac history, hemodynamic variables, or the sensitivity of the w aveform strip-chart recorder. Only the sensitivity of the waveform recorder was significantly associated with the ability to detect waveforms. Hemodyn amic waveforms cannot be distinguished in a significant number of patients by physicians using the standard PAC and recording systems used in the ICU setting. Increased recorder sensitivity will enhance the detection of wavef orm components.