ABSTRACT
Objective:
To evaluate the effects of thoracic paravertebral block (TPVB) on
graft patency in
off-pump coronary artery bypass grafting.
Methods:
Fifty American Society of
Anesthesiologists physical status Ⅱ or Ⅲ
patients,
aged 60-75 yr, weighing 50-80 kg, undergoing elective
off-pump coronary artery bypass grafting under combined intravenous-inhalational
anesthesia, were divided into 2 groups using a random number table
method:
control group (group C, n=30) and TPVB group (group T, n=20). In group T, TPVB was performed at T 4, 5 interspace under the guidance of ultrasound, a test
dose of 1%
lidocaine 5 ml was injected on both sides, and 2 min later 0.375%
ropivacaine 15 ml was injected.According to the
anatomy of
coronary artery, the
graft was divided into 4 parts left
internal thoracic artery-anterior descending branch (arterial
graft), the middle branch or the first diagonal branch, blunt marginal branche, and right posterior descending branch or left ventricular posterior branch.The
blood flow was measured and pulsatility index was calculated after
graft transplantation.
Central venous pressure, mean
pulmonary artery pressure,
cardiac output, systemic resistance index and pulmonary resistance index were recorded immediately after placement of floating
catheter (T 1), immediately after sawing
sternum (T 2), immediately after anastomosis of all
grafts (T 3) and 5 min before leaving the room (T 4). The intraoperative cardiovascular adverse events and
consumption of
sufentanil were recorded.
Results:
Compared with group G,
central venous pressure, systemic resistance index and pulmonary resistance index were significantly decreased,
cardiac output were increased, the
incidence of intraoperative
tachycardia was decreased, the
incidence of
hypotension was increased, the
consumption of
sufentanil was reduced, the flow of left
internal thoracic artery-anterior descending branch was increased, and the pulsatility index was decreased at T 3 and T 4 in group T ( P<0.05).
Conclusion:
TPVB can improve the patency of left
internal thoracic artery-anterior descending branch in
off-pump coronary artery bypass grafting.