Transthoracic monitoring of the impedance of the right lung in patients with cardiogenic pulmonary edema.
Crit Care Med
; 29(6): 1137-44, 2001 Jun.
Article
em En
| MEDLINE
| ID: mdl-11395588
ABSTRACT
OBJECTIVE:
To evaluate the suitability of the new electrical impedance monitor RS-205 for monitoring of cardiogenic pulmonary edema (CPE).DESIGN:
Prospective, controlled study.SETTING:
A department of internal medicine in a 1,200-bed university-affiliated, teaching hospital. PATIENTS Sixty patients, aged 52-80 yrs, 30 without CPE (controls) and 30 with or at high risk for CPE.INTERVENTIONS:
Internal thoracic impedance (ITI) was monitored by the RS-205. The RS-205 is approximately three times more sensitive than the Kubicek monitor, and it eliminates the effect of the drift of skin-to-electrode impedance. This is achieved by eliminating skin electrode impedance by a special algorithm, thus allowing measurement of ITI rather than total transthoracic impedance. Measuring ITI, the main component of which is lung impedance, is a noninvasive and safe method. CPE was diagnosed in accordance with well-accepted clinical and roentgenological criteria. MEASUREMENTS AND MAINRESULTS:
The controls' initial ITI was 68.3 +/- 12.38 ohms. During 6 hrs of monitoring, the ITI attained a minimum average value of -1.3 +/- 2.08% and a maximum average value of 4.6 +/- 3.56% relative to baseline. In all patients entering CPE, ITI decreased by 14.4 +/- 5.42% on the average (p <.001) 1 hr before the appearance of clinical symptoms. In patients with evolving CPE, ITI decreased significantly compared with controls (22.25 +/- 9.82%, p <.001). In patients at the peak of pulmonary edema, ITI was 2.1 times lower than in the control group (33.1 +/- 10.90 ohms, p <.001). In the last hour before the resolution of CPE, ITI increased in all patients by 17.7 +/- 19.74% compared with the peak of disease (p <.05). After the resolution of pulmonary edema, ITI increased in all patients by 44.14 +/- 26.90% compared with the peak of disease (p <.001). Importantly, the trend in ITI in all patients changed in accordance with the dynamics of CPE. A mixed general linear model shows that ITI values correlated well with the degree of crepitation, a direct characteristics of CPE.CONCLUSIONS:
The RS-205 is suitable for monitoring patients at high risk of CPE development. It enables detection of CPE and the monitoring of patients at all stages of CPE.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Edema Pulmonar
/
Cardiografia de Impedância
Tipo de estudo:
Diagnostic_studies
/
Etiology_studies
/
Evaluation_studies
/
Observational_studies
/
Prognostic_studies
/
Risk_factors_studies
Limite:
Aged
/
Aged80
/
Female
/
Humans
/
Male
/
Middle aged
Idioma:
En
Revista:
Crit Care Med
Ano de publicação:
2001
Tipo de documento:
Article
País de afiliação:
Israel