Haemodynamic modifications after unilateral subarachnoid anaesthesia evaluated with transthoracic echocardiography.
OBJECTIVE
The aim of the study is the evaluation through transthoracic echocardiography of the haemodynamic modifications due to unilateral subarachnoid anaesthesia with bupivacaine 0.5% given for orthopaedic surgery.


METHODS
In this prospective study, at the University Hospital Orthopedics surgical theater, 20 patients underwent orthopaedic surgery on the lower limbs. Unilateral spinal block was performed with hyperbaric bupivacaine 0.5%, 8 mg after a fluid challenge with saline solution 0.9%. Transthoracic echocardiography was performed and cardiac output was calculated from the left ventricular outflow tract (LVOT) with a recently validated technique. Cardiac output, stroke volume, ejection fraction, heart rate, mean arterial pressure were evaluated. These parameters were obtained before anaesthesia (t1), 5 minutes after anaesthesia (t2) and 16 minutes after anaesthesia (t3).


RESULTS
Systolic, mean and diastolic arterial pressures after 5 min and 16 min from anaesthesia significantly decreased if compared to basal time (p<0.05 and p<0.001 respectively) while cardiac index (p<0.001) and ejection fraction (p<0.05) decreased only after 16 min from subarachnoid anaesthesia.


CONCLUSIONS
Despite the fluid challenge we can not prevent a significant fall in the blood pressure and a decrease of the left ventricular function calculated with the decrease of cardiac output and of the left ventricular ejection fraction.
Donati
A
A
Institute of Medical and Surgical Emergencies, Marche Politecnic University, Ancona, Italy. donati@indi.it
Mercuri
G
G
Iuorio
S
S
Sinkovetz
L
L
Scarcella
M
M
Trabucchi
C
C
Pelaia
P
P
Pietropaoli
P
P
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000775:Anesthesia, Spinal; D000777:Anesthetics; D004452:Echocardiography; D005260:Female; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D019637:Orthopedic Procedures; D011446:Prospective Studies; D013346:Subarachnoid Space
D000777:Anesthetics