CARDIOVASCULAR JOURNAL OF AFRICA • Vol 23, No 8, September 2012
430
AFRICA
pressure, systolic blood pressure, diastolic blood pressure,
central venous pressure, cardiac index and the presence of
arrhythmias were documented. Other independent variables such
as urinary output, serum electrolytes and serum creatinine levels
were measured immediately after discontinuation of CPB, before
transferring the patient to the ICU, immediately after arriving in
ICU, and after two, four, six, 12 and 24 hours in ICU.
Study approval was obtained from the ethics committee of
our Centre and written informed consent was obtained from the
patients. The data were put into spreadsheets and comparison
of variables between groups was done using Chi-squared or
ANOVA tests.
Results
Biometric data were similar in all groups. Mean anaesthesia
time, pump time and cross-clamp time were the same in all three
groups (Table 1). There were no mortalities in any of the groups.
There were no significant differences in systolic and diastolic
blood pressure between the three groups, and haemoglobin,
blood urea nitrogen (BUN), creatinine, Na and K levels, partial
thromboplastin time (PTT), and international normalised ratio
(
INR) were same in the three groups. No case was excluded from
this survey and no significant differences were found between
groups for mean arterial pressure, central venous pressure and
heart rate (Table 2).
The volume needed for maintaining normal blood pressure
and central venous pressure in the range of 7–14 mmHg was
less in the HES group than in the other groups, but similar in the
gelatin and Ringer’s groups in the first 24 hours after surgery.
Urinary output in the first four and 24 hours after surgery was
significantly higher in the HES group than in the other two
groups.
Mean creatinine levels on the first day post operation were
1.25
±
0.23
mg/dl in the Ringer’s group, 1.3
±
0.24
mg/dl in
gelatin group and 1.06
±
0.13
mg/dl in the HES group. On the
second day post operation, these values were 1.4
±
0.25, 1.41
±
0.26, 1.13
±
0.16
mg/dl in the Ringer, gelatin and HES group,
respectively. Mean creatinine levels were significantly lower in
the HES group (Table 3).
There were no significant differences between the three
groups in the amount of blood, FFP and platelet transfusions in
the ICU (Table 3). Arrhythmias in ICU, extubation time and ICU
stay were the same in all groups (Table 4).
Discussion
The main result of this study was that haemodynamic stability
could be achieved after CABG surgery with less volume of HES
than gelatin and Ringer’s solutions. The kidney function was
better in the short term in the HES group than in the other two
groups.
In our centre, we selected adult patients for CABG. We are
aware that enough of a suitable volume expander is needed for
haemodynamic stability after CABG, and that some volume
expanders have side effects. Patients usually have a systemic
inflammatory response after CPB for CABG and the resultant
endothelial damage leads to hyperpermeability and interstitial
oedema.
4
Some researchers have shown that HES reduced inflammation
and endothelial damage.
4
It also maintained the cell’s integrity
and function.
4,9
Lower-molecular weight HES molecules had
an effect on the arteriolar integrity and could reduce arteriole-
induced oedema in clinical and experimental models.
10
Reported
effects of HES usage were improvement in the microcirculation
TABLE 2. COMPARISON OF DETERMINEDVARIABLES
BETWEEN THE THREE GROUPS (
±
SD)
Ringer’s
solution
Gelatin
(4%)
HES
(6%)
p
-
value
MAP after pump
61 (4)
63 (4)
64 (4)
0.410
MAP after moving to ICU
62 (3)
61 (3)
63 (4)
0.380
MAP after 2 hours in ICU 64 (4)
67 (3)
68 (4)
0.395
MAP after 4 hours in ICU
67 (5)
69 (6)
71 (7)
0.295
MAP after 6 hours in ICU 69 (5)
73 (4)
74 (7)
0.220
MAP after 12 hours in ICU 74 (9)
73 (11)
75 (10)
0.345
MAP after 24 hours in ICU 73 (7)
71 (4)
75 (5)
0.275
HR after moving to ICU 62 (3)
64 (5)
68 (6)
0.175
HR after 2 hours in ICU 73 (7)
74 (5)
72 (4)
0.195
HR after 4 hours in ICU 77 (7)
81 (6)
78 (5)
0.170
HR after 6 hours in ICU 75 (7)
80 (6)
78 (6)
0.220
HR after 12 hours in ICU 77 (7)
79 (5)
80 (6)
0.230
CVP after pump
11 (10–14) 12 (10–14) 12 (10–14) 0.270
CVP after moving to ICU 12 (10–14) 11 (10–14) 13 (10–14) 0.215
CVP after 2 hours in ICU 13 (10–14) 12 (10–14) 11 (10–14) 0.179
MAP: mean arterial pressure, HR: heart rate, CVP: central venous pressure
TABLE 3. COMPARISON OF DETERMINEDVARIABLES
BETWEEN THE THREE GROUPS (
±
SD)
Ringer’s
solution
Gelatin
(4%)
HES
(6%)
p
-
value
Mean volume infused
during surgery (ml)
2150 (340) 1925 (290) 1320 (250) 0.011
Mean volume infused in
first 24 hours in ICU (ml)
6100 (400) 5300 (380) 3500 (210) 0.001
Units of packed cells
infused in 24 hours in ICU
94
93
96
0.275
Units of FFP infused in 24
hours in ICU
53
53
48
0.170
Units of platelets infused
in 24 hours in ICU
28
34
23
0.145
Amount of haemorrhage
in first 24 hours (ml)
1300 (260) 1350 (270) 1280 (280) 0.170
Amount of urine output in
first 4 hours in ICU (ml)
1700 (180) 1760 (190) 2250 (290) (0.02)
Amount of urine output in
first 24 hours in ICU (ml)
4450 (310) 4520 (340) 5200 (330) (0.03)
Creatinine in first
postoperative day (mg/dl)
1.32 (0.23) 1.31 (0.24) 1.06 (0.13) 0.004
Creatinine in second
postoperative day (mg/dl)
1.4 (0.25) 1.41 (0.26) 1.13 (0.16) 0.004
TABLE 4. COMPARISON OF DETERMINEDVARIABLES
BETWEEN THE THREE STUDIED GROUPS (
±
SD)
Ringer’s
solution
Gelatin (4%)
HES (6%)
p
-
value
Extubation
time (min)
452 (418–508) 445 (410–500) 463 (420–430) 0.215
ICU stay time
(
hours)
46 (42–48)
47 (43–48)
45 (42–48)
0.175
Arrhythmias in
ICU (n)
2
0
2
0.459
