[The usefulness of bioimpedance in patient monitoring in an intensive-therapy heart-surgery unit: a comparison with thermodilution].
Haemodynamic monitoring of intensive care unit (ICU) patients can be carried out by thermodilution system. This method is invasive, does not give a continuous monitoring and complications can occur. Thoracic electrical bioimpedance (TB), a non invasive, fast, easily repeatable method, is able to measure some important haemodynamic parameters: end diastolic volume (EDV), stroke volume, cardiac output (CO), ejection fraction (EF), some contractility indexes, systemic vascular resistances (SVR) and cardiac work. The aim of the present study is to compare CO and SVR obtained by thermodilution with the same indexes obtained by TB. Therefore, 20 ICU patients (12 males and 8 females, mean age 54 +/- 11 years) were studied. Out of them, 16 had been submitted to cardiac surgery in the previous 7 days and 4 were waiting for cardiac surgery. The patients were divided in 2 groups: Group A (N 4) included patients with valvular malfunction and/or cardiac arrhythmias and Group B (N 16) included patients with normal valvular function and sinus rhythm. CO obtained by TB was well related with the one obtained by invasive (INV; r = 0.878; p < 0.001). The mean value of difference of the 2 methods was 12.29 +/- 11.83 for the whole group of 20 patients but it was 26.07 +/- 14.16 in the Group A and 8.84 +/- 8.09 in the Group B confirming the less reliability of the method in patients with abnormal valvular function or in the presence of cardiac arrhythmias. As a consequence, SVR obtained by TB and INV resulted well related (r = 0.752; p < 0.001). The mean value of differences was 11.14 +/- 9.01 in the group of 20 patients and particularly 19.55 +/- 10.87 in the Group A and 9.04 +/- 7.07 in the Group B. In a subgroup of 9 patients, CO was measured at successive times (0, 30, 60, 90 min) by both TB and INV; when comparing the 2 CO values a significant correlation was observed. In conclusion, TB represents a valid method in haemodynamic monitoring of the ICU patients.
Ferraro
S
S
Dipartimento di Cardiologia e Cardiochirurgia, II Facoltà di Medicina e Chirurgia, Università degli Studi Federico II, Napoli.
D'Alto
M
M
Maddalena
G
G
Golino
A
A
Liguori
L
L
Jannelli
G
G
Spampinato
N
N
Chiariello
M
M
D000328:Adult; D000368:Aged; D006348:Cardiac Surgical Procedures; D002407:Catheterization, Swan-Ganz; D003422:Critical Care; D017097:Electric Impedance; D005069:Evaluation Studies as Topic; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000379:methods* / Q000706:statistics & numerical data; D011182:Postoperative Care; D013815:Thermodilution / Q000379:methods / Q000706:statistics & numerical data
Utilità della bioimpedenza nel monitoraggio del paziente in unità di terapia intensiva di cardiochirurgia: comparazione con la termodiluizione.