Right heart catheterization at bedside: a note of cautious optimism

A computer program for interpreting pulmonary artery catheterization data: results of the European HEMODYN Resident Study

We previously validated an expert computer program (Hemodyn) designed to assist in interpreting pulmonary artery catheterization data. The present multicentric study assessed the influence of Hemodyn on the therapeutic strategies of residents. Each resident made several diagnostic choices and suggested appropriate treatments based on pulmonary artery catheterization (PAC) data. After knowledge of the computer interpretation, the resident could either maintain or change his or her diagnosis and treatment under a senior supervision. Agreement between the residents' initial evaluation and the computer's was poor (kappa <0.6). After computer assistance, agreement improved dramatically (kappa >0.9). Computer assistance led the residents to change at least one suggested treatment in 63% of cases, and in 8% of cases the residents changed the initial suggestion to its opposite. Expert software capable of helping residents to interpret PAC data properly may improve the quality of care given to critically ill patients.

Haemodynamic monitoring and liver function evaluation by pulsion cold system Z-201 (PCS) during orthotopic liver transplantation

Pulsion cold system (PCS, COLD) is a haemodynamic monitoring system that allows measurement of cardiac output (CO), partial blood volumes, lung water, and liver function. The aim of the study was to evaluate this monitoring system during human orthotopic liver transplantation (OLT) for the following: (a) to determine agreement between CO measurements via pulmonary artery thermodilution (CO TDpa), and aortic transpulmonary thermodilution (CO TDa); (b) to compare the preload dates obtained with the COLD with central venous pressure (CVP) and pulmonary capillary wedge (PCWP); and (c) to assess the use of the plasma disappearance rate (PDR) of indocyanine green (ICG) as a measure of graft function. Fifteen consecutive patients undergoing OLT were studied. Each patient received a pulmonary artery catheter and a 5F aortic catheter with an integrated thermistor. The thermistor of the aortic catheter were connected to one computer system (COLD-Z201, Pulsion Medical Systems, Munich, Germany). Haemodynamic data were registered an all the phases of OLT. PDR was measured during surgery in 12 patients. Correlations between PDR and the other markers of graft function (transaminases, protrombine time, and bile production) were sought. The correlation coefficient between CO TDa (COLD) and CO TDpa was r = 0.766 (p < 0.001), and an additional analysis according to Bland-Altman was also performed. There was a better correlation between the cardiac index (determined by two monitoring systems) and the volume measurements than the correlation observed with pressure preload parameters. The best correlations were found between the cardiac index in the femoral artery and intrathoracic blood volume index (ITBVI) and pulmonary blood volume index (PBVI) (r = 0.79 and r = 0.72, respectively; p < 0.01). PDR measured in the group patients with bad early graft function were lower (13.6 +/- 2.7) than those in the group with a good graft function (21.6 +/- 9) (p < 0.05). The degree of discrepancy between femoral and pulmonary thermodilution cardiac output measures is very wide during OLT so as to make the techniques using the COLD machine clinically useless. On the other hand, the volumes measured by COLD, specially ITBVI and PBVI, are more useful to asses the pre-load than pressure measurements. In OLT, the PDR measured within the first few hours after liver reperfusion may become a useful tool for early diagnosis of primary graft dysfunction (PDF).

Pulmonary artery catheter: does the problem lie in the users?

The aims of this study were to look for the variability in the treatment of circulatory shock and to assess the extent to which this variability was reduced by pulmonary artery catheterization (PAC). At three international conferences in 1997-1998 (European Society of Critical Care Medicine, French Language Society for Critical Care [Société de Réanimation de Langue Française], and Society of Critical Care Medicine), a real-life clinical case was discussed in meetings among physicians and a panel of experts, with assistance from an expert computer program. A total of 417 physicians took part in the discussions. Following the clinical presentation, only 38% of physicians suggested the same treatment as the experts, and 35% suggested potentially harmful treatments. Complete hemodynamic data from PAC significantly decreased the range of suggested treatments, improved agreement among physicians themselves as well as the agreement between physicians and experts, and decreased the number of potentially harmful propositions. However, whereas almost 80% of participants finally agreed on the treatment after one to three invasive hemodynamic sets of measurements, at least 10% persisted in suggesting potentially harmful treatments. PAC improved interphysician agreement, but our data suggest that yet greater agreement could be achieved by improving the theoretical training of practitioners.

Intensive care physicians' insufficient knowledge of right-heart catheterization at the bedside: time to act?

OBJECTIVE

To evaluate French, Swiss, and Belgian intensive care physicians' knowledge about the pulmonary artery catheter.

DESIGN

Survey study by questionnaire.

SETTING

Eighty-six European university and nonuniversity intensive care units (ICUs).

SUBJECTS

One hundred thirty-four ICUs identified from the directories of two European intensive care medicine societies were asked to participate. Five hundred thirty-five critical care physicians working in 86 ICUs participated.

INTERVENTIONS

In any particular ICU, all physicians were to complete--simultaneously, anonymously and without prior notice--a multiple choice questionnaire consisting of 31 questions regarding all aspects of bedside pulmonary artery catheterization. This questionnaire was the same one already used and extensively validated in a similar study conducted several years earlier in the United States and Canada.

MEASUREMENTS AND MAIN RESULTS

The percentage of correct answers per participant (score) was tabulated. Sixty-eight percent of respondents still in training (n = 232) believed that their knowledge of the pulmonary artery catheter was less than adequate; 36% of those who had completed their postgraduate training (n = 294) also believed their knowledge to be inadequate. The mean score of all respondents was 72.2 +/- 14.4%, significantly lower (p <.0001) in case of uncompleted postgraduate training (67.3 +/- 14.7%, lower quartile 56.7%, median 70.0%, upper quartile 76.7%), as compared with completed postgraduate training (76.1 +/- 13.0%, lower quartile 70.0%, median 80.0%, upper quartile 86.7%). When using multivariate analysis, the location of the ICU in a university hospital, the belief of respondent that his/her knowledge of the pulmonary artery catheter was adequate, and the responsibility for supervising catheter insertion were the only independent predictors of good performance on the questionnaire (p < .001 for all three variables). It was impossible to identify any subcategory of physicians with a uniformly good knowledge of the pulmonary artery catheter. The proportion of incorrect answers to some basic items was disturbingly high. For instance, approximately 50% of the respondents, whether trained or in training, did not correctly identify pulmonary artery occlusion pressure from a clear chart recording.

CONCLUSIONS

Knowledge of right-heart pulmonary artery catheterization is not uniformly good among ICU physicians. Accreditation policies and teaching practices concerning this technique need urgent revision.