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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 27, No 3, May/June 2016
AFRICA
173
Re-exploration for mediastinal bleeding is considered a
major complication and was necessary in 31 patients (1.8%).
Mediastinal drainage was measured over 48 hours. The average
bleeding plus one standard deviation was considered major
bleeding. A calculated volume of 1 070 ml per 48 hours was
therefore considered important. There were 180 (10.3%) such
patients. Table 9 illustrates the association between bleeding and
mortality. The significant difference between 9.4 and 2.0% had a
p
-value of
<
0.0001.
Cardiac surgery is an important consumer of homologous
blood products. Of these 1 750 patients, only 404 (23.2%)
patients actually received blood products. Almost a quarter of
this surgical population depended on the blood bank for red
blood cells (RBC), plasma and/or platelets. The close association
between risk, mortality and blood bank usage is demonstrated
in Table 10. The risk and outcome between the group with three
and more units of RBC and those with less differed considerably
(
p
<
0.0001).
Length of stay
The average length of stay (LOS) of the 1 697 patients who left
hospital was 6.0 days (2–83 days, median 5). LOS is an indication
of recovery and that should correlate with age and risk for
mortality. Tables 11 and 12 confirmed this. For isolated CABG
(
n
=
1 628 patients) 63.8% of patients stayed five days and less in
hospital, whereas only 2.2% stayed longer than two weeks.
Discussion
The exposition of such surgical outcome data might appear like
basic auditing of a practice, yet one should always be attuned
to more wisdom. The scientist looks for wisdom of
theoria
and
the surgeon evaluates for wisdom of
techn
ē
. A practical wisdom
obtained with a process of hermeneutics against a certain
traditional background, such as faith, is referred to as
phron
ē
sis.
26
Mortality rate is one way of assessing outcome, but favourable
mortality rates could also indicate limited morbidity and even
long-term survival.
27
Registries provide a more accurate picture
of mortality as an outcome. In fact, published articles under-
represent mortality rate up to 50% lower than a database.
27
A
statistical comparison between the local outcome and records
from both sides of the Atlantic Ocean and Japan was not
possible and the reader is left with a visual comparison. Table 13
displays such a comparison with other databases.
Mortality could also be defined as death within 30 days,
even if the patient had been discharged. Locally, the majority
of patients are from outside the city where surgery is performed
and follow up is limited. To balance the odd patient who might
have died at home within 30 days are those cases where the
patient died after several weeks in hospital with, for example,
respiratory failure or after a second operation. They were all
considered as primary cardiac surgical mortalities. Decanting
refers to transferring a critical patient to a second facility and so
the mortality or morbidity is erased.
28
This was not and is still not
the practice in Bloemfontein.
The determination of the aetiology of death is not simple and
could differ from surgeon to surgeon. In the
Tabula viva chirurgi
it seems most patients died due to a non-cardiac system failure
(Table 3). A post mortem is done only in cases of death in theatre
or in cases where the patient has not woken up. That being said, a
routine post mortem is not always clarifying.
29
The phase-of-care
mortality analysis (POCMA) identifies an identifiable trigger
for a fatal course.
30
These five phases are pre-operative, the
operation itself, while the patient is in intensive care, in the ward,
and during the discharge phase. Such a seminal event leading
Table 8. Patients with associated major complications
Number of patients
With major complication
Mortality (%)
94
Single
17 (18.1)
23
Double
12 (52.2)
5
Triple
2 (40.0)
1 623*
None
17 (1.0)
*Five patients died in theatre and had no major complications.
The number of patients was 1 750 (5 + 94 + 23 + 5 + 1 623).
The number of deaths was 53 (5 + 17 + 12 + 2 + 17).
Table 9. Outcome associated with mediastinal drainage
Drainage
Number (%)
Mortality (%)* Re-exploration (%)
≥
1 070 ml
180 (10.3)
17 (9.4)
29 (16.1)
<
1 070 ml
1 565 (89.7)
31 (2.0)
3 (0.2)**
*Five patients died in theatre (total mortality 53).
**The re-explorations were in two patients who drained 950 and 975 ml and the
third patient had to be re-opened to remove a surgical instrument.
Table 10. Risk, mortality and blood bank usage
Blood bank usage*
EuroSCORE Mortality (%)
No bank blood (
n
=
1 346)
3.43
23 (1.7)
Bank blood (
n
=
404)
5.33
30 (7.4)
Only 1–2 units RBC (
n
=
222)
4.95
6 (2.7)
≥
3 units RBC (
n
=
123)
6.05
20 (16.3)
RBC, red blood cells. *Bank blood includes red blood cells, plasma and/or
platelets.
Table 11. Length of stay and age
Total group
(
n
=
1 697)
Median (days)
Age (years)
5
≤ 39 (
n
=
39)
4
40–49 (
n
=
203)
4
50–59 (
n
=
495)
5
60–69 (
n
=
584)
5
70–79 (
n
=
346)
6
≥
80 (
n
=
30)
9
Table 12. Length of stay and EuroSCORE
Total group
(
n
=
1 697)
Median (days)
EuroSCORE
5
≤ 2 (
n
=
630)
5
3–5 (
n
=
644)
5
6–9 (
n
=
365)
6
≥
10 (
n
=
58)
10
Table 13. Comparison of isolated CABG mortality with other databases
Databases
Year
Number
Mortality (%)
Tabula viva chirurgi
2000–2012
1 628
2.21
EuroSCORE
23
1998
12 103
3.40
STS
22
2000–2006
774 881
2.30
JACVSD
35
2000–2005
7 133
2.72
JACVSD, Japan Adult Cardiovascular Surgery Database; STS, Society of
Thoracic Surgeons.