Y. Niimi et al., ECHOCARDIOGRAPHIC EVALUATION OF GLOBAL LEFT-VENTRICULAR FUNCTION DURING HIGH THORACIC EPIDURAL-ANESTHESIA, Journal of clinical anesthesia, 9(2), 1997, pp. 118-124
Objectives: To assess the effects of high thoracic epidural anesthesia
on left ventricular (LV) diastolic filling and systolic function in p
atients without heart disease. Design: Prospective study. Setting: Uni
versity hospital. Participants: 24 ASA physical status I and II patien
ts scheduled for elective noncardiac surgery. Interventions: Patients
received high thoracic (HTE; n = 12) or low thoracic (LTE; n = 12) epi
dural anesthesia. Measurement and Main Results: Left ventricular diast
olic filling was noninvasively determined by precordial echocardiograp
hy using a pulsed Doppler technique and with a newly developed acousti
c quantification (AQ) method that automatically detects endocardial bo
rders and measures cavity area. All measurements were performed in awa
ke premedicated patients. In the HTE group, the extent of sensory bloc
kade of T-1-T-5, at the least, was induced with 2% lidocaine 5 ml. Dur
ing HTE, systolic blood pressure (119 +/- 16 vs. 108 +/- 14 mmHg, p <
0.01), heart rate (73 +/- 9.8 vs. 63 +/- 6.8 beats/min, p < 0.01), car
diac output (CO; 4.5 +/- 1.1 vs. 3.8 +/- 1.2 L/min, p < 0.05), and fra
ctional area change (50 +/- 11 vs. 37 +/- 11%, p < 0.01) decreased sig
nificantly, whereas end diastolic area (9.4 +/- 1.4 vs. 10.3 +/- 1.1 c
m(2) p < 0.01) and end systolic area (4.8 +/- 1.3 vs. 60 +/- 1.1 cm(2)
, p < 0.05) showed a significant increase. As a result, stroke volume
was kept constant (63 +/- 14 vs. 60 +/- 19 ml). Pulsed Doppler derives
indices such as peak velocity during the early filling (E) and the at
rial contraction (A) phases, peak early to atrial velocity ratio (E/A)
, and acceleration time remained unchanged. AQ derived peak dA/dt duri
ng the early diastolic (D1) and the atrial contraction phases (D2) and
D1/D2 also remained unchanged. In contrast, in the LTE group, no sign
ificant differences were noted in all systolic and diastolic indices o
btained by poised Doppler and AQ method. Conclusions: High thoracic ep
idural anesthesia causes a decrease in CO without changing LV ejection
and diastolic filling performance in healthy subjects. (C) 1997 by El
sevier Science Inc.