Hemodynamic, Hepatorenal, and Postoperative Effects of Desflurane-Fentanyl
and Midazolam-Fentanyl Anesthesia in Coronary Artery Bypass Surgery
A. Kadir But, MD, Mahmut Durmus, MD, H. Ilksen Toprak, MD, Erdogan Ozturk, MD, Semra Demirbilek, MD,
and M. Ozcan Ersoy, MD
Objective: The purpose of this study was to compare the
hemodynamic, hepatorenal, and postoperative effects of
desflurane-fentanyl and midazolam-fentanyl anesthesia dur-
ing coronary artery bypass surgery.
Design: Prospective study.
Setting: University hospital.
Participants: Sixty patients undergoing elective coronary
artery bypass grafting surgery with ejection fraction more
than 45%.
Interventions: Anesthesia was induced with etomidate,
0.2 mg/kg, and fentanyl, 5 g/kg, in group D (n 30) and
with midazolam, 0.1 to 0.3 mg/kg, and fentanyl, 5 g/kg, in
group M (n 30). Anesthesia was maintained with desflu-
rane, 2% to 6%, and fentanyl, 15 to 25 g/kg, in group D and
midazolam infusion, 0.1 to 0.5 mg/kg/h, and fentanyl, 15 to
25 g/kg, in group M.
Measurements and Main Results: Hemodynamic monitor-
ing included a 5-lead electrocardiogram, a radial artery cath-
eter, and a pulmonary artery catheter. Data were obtained
before induction of anesthesia (t
0
), after induction of anes-
thesia (t
1
), after intubation (t
2
), after surgical incision (t
3
),
after sternotomy (t
4
), before cardiopulmonary bypass (t
5
),
after protamine infusion (t
6
), and at the end of the surgery
(t
7
). Blood samples were obtained to measure total bilirubin,
aspartate aminotransferase, gamma glutamyl transferase,
lactate dehydrogenase, alkaline phosphatase, creatinine,
and blood urea nitrogen just before induction of anesthesia
and at the first, fourth, and 14th days postoperatively.
Conclusions: Intraoperative hemodynamic responses were
similar in both groups, and transient hepatic and renal dys-
functions were observed in the postoperative period in both
groups. The extubation and intensive care unit discharge times
were found to be shorter in the desflurane-fentanyl group.
© 2005 Elsevier Inc. All rights reserved.
KEY WORDS: coronary artery bypass grafting, desflurane,
midazolam, kidney, liver, postoperative effects
I
T HAS BEEN SUGGESTED that the temporary and mild-
to-moderate disruption in hepatic and renal functions after
cardiac surgery is more frequent than expected and has a direct
influence on morbidity.
1
Factors thought to be responsible are
the preoperative cardiac state, presence of an accompanying
systemic illness, perioperative hemodynamic state, surgical
procedure, hypothermia, and cardiopulmonary bypass (CPB).
2
In addition, influences of the anesthetic technique on hepatic
and renal functions are debated.
Desflurane and midazolam are frequently used anesthetic
agents during cardiac surgery. Their pharmacokinetic and phar-
macodynamic properties allow earlier tracheal extubation with-
out compromising intraoperative hemodynamic stability.
3,4
Al-
though several hemodynamic studies including comparison of
different anesthetic agents exist in the literature, the studies
regarding the effects of desflurane and midazolam on cardiac
and hepatorenal functions after cardiac surgery are not ade-
quate. In this study, the authors aimed to compare the hemo-
dynamic, hepatorenal, and postoperative effects of desflurane-
fentanyl and midazolam-fentanyl anesthesia during cardiac
surgery.
METHODS
After obtaining informed consent from the patients and approval
from the ethics committee, 60 patients undergoing elective coronary
artery bypass grafting (CABG) surgery were included in the study.
Patients with diabetes mellitus, bleeding disorders, ejection fractions
45%, and renal or hepatic failure were excluded. Patients were
classified into desflurane (group D, n = 30) and midazolam (group M,
n = 30) groups. The patients continued their medications including the
morning of surgery. All patients were premedicated orally with 5 mg of
diazepam 2 hours before the induction of anesthesia. In the operating
room, veins on both arms were cannulated with 16-G catheters after a
5-lead electrocardiogram and SpO
2
monitoring (Dräger PM 8040-Cato,
Lübeck, Germany). All patients were given 8 mL/kg of normal saline
for prehydration. Radial artery cannulation (20-G catheter) and pulmo-
nary artery cannulation (4-lumen thermodilution catheter, 7.5F, 110 cm,
Abbott Labs, Zwolle, the Netherlands) were placed by way of the left
radial artery and right internal jugular vein, respectively, under local
anesthesia. The saline infusion rate was standardized for every patient
as 5 mL/kg during the operation. Anesthesia was induced with 2%
lidocaine, 1 mg/kg, etomidate, 0.2 mg/kg, and fentanyl, 5 g/kg, in
group D and 2% lidocaine, 1 mg/kg, midazolam, 0.1 to 0.3 mg/kg, and
fentanyl, 5 g/kg, in group M. Tracheal intubation was facilitated with
vecuronium, 0.1 mg/kg, in both groups. The patients were ventilated
manually with 100% O
2
until intubation and mechanically thereafter
with Dräger, Cato (Lübeck, Germany) edition, (end-tidal CO
2
partial
pressure 35-40 mmHg). N
2
O was not administered in either group, and
anesthesia was maintained with desflurane, 2% to 6%, and fentanyl, 15
to 25 g/kg, in group D and midazolam, 0.1 to 0.5 mg/kg/h, and
fentanyl, 15 to 25 g/kg, in group M. In both groups, doses of the
anesthetics used were adapted to maintain optimal anesthetic and
surgical conditions, while maintaining hemodynamic stability. The
total fentanyl dose administered was recorded, and the administration
times of fentanyl were standardized as during induction, before inci-
sion, before sternotomy, and before and during CPB in either group.
A roller pump (Cobe Cardiovascular Inc, Arvada, CO), a hollow-
fiber membrane oxygenator (Dideco D 708 Simplex, Mirandola, Italy),
a polyvinylchloride tubing set, a 2-stage venous cannula, a venous
reservoir (Dideco D 740, Simplex), and an arterial filter (Dideco D 734
Micro 40, Simplex) were used for CPB. The circuit was primed with
1,600 mL of Ringer’s lactate, 150 mL of mannitol, 1 g of ceftizoxime,
and 2,500 IU of heparin. Mild systemic hypothermia (33°C) was
achieved using the nonpulsatile pump flow of 2.0 to 2.4 L/min/m
2
.
During CPB, hematocrit was maintained between 20% to 25%, and the
mean arterial pressure was maintained between 50 to 70 mmHg (with
sodium nitroprusside or phenylephrine hydrochloride administration as
required). Anticoagulation was obtained by the administration of bo-
From the Department of Anesthesiology, Inonu University School of
Medicine, Malatya, Turkey.
Address reprint requests to A. Kadir But, MD, Department of Anes-
thesiology, Inonu University School of Medicine, T. Ozal Tip Merkezi
Anesteziyoloj, Malatya 44315, Turkey. E-mail: kbut@inonu.edu.tr
© 2005 Elsevier Inc. All rights reserved.
1053-0770/05/1905-0006$30.00/0
doi:10.1053/j.jvca.2004.10.009
597 Journal of Cardiothoracic and Vascular Anesthesia, Vol 19, No 5 (October), 2005: pp 597-602