Haemodynamic parameters obtained by transthoracic echocardiography and Swan-Ganz catheter: a comparative study in liver transplant patients.

OBJECTIVE: To compare the haemodynamic measurements of cardiac output (CO), central venous pressure (CVP), pulmonary capillary wedge pressure (Pw) and pulmonary artery systolic pressure (PASP), obtained by Swan-Ganz catheter and transthoracic echocardiography. MATERIAL AND METHODS: Prospective study in a Medical/Surgical Intensive Care Unit (ICU). A total of 41 post liver transplant patients were enrolled. CO, CVP, Pw and PASP, were simultaneously determined by two independent observers, utilizing a Swan-Ganz catheter and transthoracic echocardiography, using equations described in the literature. A linear correlation and a Bland-Altman analysis were performed. RESULTS: A good correlation between invasive and non- invasive measurements for CO (r=0.97) and CVP (r=0.88) was found, but determinations of Pw (r=0.41) and PASP (r=0.18) did not correlate well. Bias and 95% confidence interval for CO were negligible namely when a CO<6 l/min was considered. Pulsed-wave Doppler-echocardiography underestimates the CO when compared with thermodilution, but the 2 techniques agree on average and can be used interchangeably. CONCLUSIONS: The non-invasive determination of CO in critical care post liver transplant patients correlates well with the invasive determinations. Transthoracic echocardiography was not appropriate for calculating filling parameters studied. Although the data was obtained in post liver transplant patients, they could be useful in defining the role of echocardiography in the ICU.

[Lymphopenia in patients submitted to assisted ventilation due to aggravated chronic respiratory failure: a prospective study]. / Linfopénia em doentes submetidos a ventilação mecânica por exacerbação de insuficiência respiratória crónica: estudo prospectivo.

OBJECTIVES: Evaluate and characterize lymphopenia in patients admitted to the Intensive Care Unit (ICU) for mechanical ventilation due to aggravated chronic respiratory failure and its probable relation to severity. MATERIAL AND METHODS: Prospective study over a period of 6 months with another 6 months follow-up after ICU discharge. The study included 24 patients, 22 males, with mean APACHE II of 19,7, three of whom with capacity for outpatient follow-up. Lymphocyte subpopulations were determined on admission and every 7 days after mechanical ventilation. Patients with evidence of infection or previous immunossupression, with the exception of steroids, were excluded from the study. RESULTS: Lymphopenia was found in 79,2% of patients with depletion of all lymphocyte series, although with greater expression for B lymphocytes CD19+. This depletion showed no relation with serum steroid levels, and although related to greater clinical severity, no correlation was found with mortality. Lymphocyte values recovered progressively during admission. CONCLUSIONS: Lymphopenia is frequent among ventilated patients with chronic respiratory exacerbation. It's a non-selective depletion, more evident with CD19+ B lymphocytes. These patients present higher severity scores but no difference in mortality. Outpatient follow-up was difficult and inconclusive.

Cardiac Doppler variation with volume status changes in general intensive care.

The authors studied the effect of volume status modification on cardiac Doppler features, with negative fluid balance and corresponding central venous pressure change. This was carried out in 64 patients admitted to the Intensive Care Unit, 24 of whom were under mechanical ventilation. With volume status change, the mitral E/A ratio showed a tendency to decrease, mitral E wave deceleration time decreased, isovolumic relaxation time increased, and the expiratory diameter of the inferior vena cava reduced and its inspiratory collapse increased. No significant correlation was observed between the parameters studied and volume changes, or between central venous pressure and fluid balance. Volume changes in critical care patients modify certain features of Doppler echocardiography, but the magnitude of such variations is unpredictable.