Py. Gueugniaud et al., CONTINUOUS ESOPHAGEAL AORTIC BLOOD-FLOW ECHO-DOPPLER MEASUREMENT DURING GENERAL-ANESTHESIA IN INFANTS, Canadian journal of anaesthesia, 44(7), 1997, pp. 745-750
Purpose: Invasive haemodynamic monitoring during general anaesthesia i
n infants is usually limited to very high risk operations, such as car
diac surgery. Nevertheless, different surgical procedures and/or anaes
thetic techniques justify additional monitoring for children, as for a
dults. The aim of this preliminary study was to evaluate the feasibili
ty of using a new echo-Doppler device (Dynemo 3000(R)) capable of meas
uring continuous aortic blood flow during general anaesthesia in infan
ts. Methods: Aortic blood flow (ABF) was measured with a small oesopha
geal probe designed for newborns and infants. The aortic flowmeter was
connected with satellite devices to visualise the haemodynamic profil
e which included ABF; pre-ejection period (PEPi), left ventricular eje
ction time (LVETi), mean arterial pressure, heart rate, stroke volume
and systemic vascular resistance. Twelve infants, aged 8-26 mo, underg
oing surgery under general anaesthesia were successively included in t
he evaluation of this device. Isoflurane (1% end-expired concentration
) was introduced to maintain anaesthesia after induction with halothan
e, midazolam, fentanyl and atracurium. Results: Correct positioning of
the probe was easily obtained in all cases and the recording quality
was excellent, whatever the operative position. Recordings of haemodyn
amic data showed some myocardial depression from isoflurane: decreased
ABF (indexed to body surface area) and lengthened PEP/LVET (2.24 +/-
0.53 L.min(-1).m(-2) and 0.32 +/- 0.05 respectively, before introducti
on of isoflurane and 1.71 +/- 0.53 L.min(-1).m(-2) (P = 0.027) and 0.3
9 +/- 0.06 (P = 0.007) with isoflurane). Conclusion: These preliminary
results suggest that this continuous ABF echo-Doppler device may be v
aluable for peri anaesthetic monitoring in infants.