Fræðigrein

Introduction: Postoperative bleeding is a common and potentially fatal complication following open heart surgery, studies reporting a reoperation rate for bleeding in the range of 2-6%. Surgical outcome after such reoperations has not been previously studied in Iceland.

Material and methods: In this retrospective study were included all adults that underwent open heart surgery in Iceland during a 6 year period, between January 1, 2000 and December 31, 2005.

Results: There were 103 reoperations (mean age 68 years, 76% males), but throughout the same 6 year period a total of 1295 open heart procedures were performed, the reoperation-rate being 8%. One third of all patients were on aspirin and 8% on clopidogrel less than 5 days before surgery. The bleeding in the primary operation averaged 1523 ml (range 300-4780) and 3942 ml for the first 24 hours postoperatively. Half of the patients were reoperated on within 2 h and 97% within 24 hours. The patients received on average 16.5 units of packed cells, 15.6 units of plasma and 2.3 sets of thrombocytes. The most common postoperative complication was atrial fibrillation (58.3%), pleural effusion that needed chest tube drainage (24.3%), myocardial infarction (23.3%) and sternal wound infection (11.7%). Median length of stay was 14 days (range 6-85), including 2 days (range 1-38) in ICU. Operative mortality was 15.5% and 1 year crude survival 79.6%.

Conclusion: Reoperation-rate for bleeding was 8%, which is higher compared to other studies. Bleeding is a serious complication following open heart surgery with high morbidity and significant mortality.

Icel Med J 2009; 95: 567-573.

 

 

Table I.       Number and rate (%) of reoperations for bleeding following open heart surgery in Iceland 2000-2005.

Ár	Number of open heart procedures	Number of reoperation	Rate of reoperations for bleeding
2000	242	13	5.4%
2001	230	24	10.4%
2002	196	22	11.2%
2003	223	17	7.6%
2004	193	14	7.3%
2005	211	13	6.2%
Total	1295	103	8%

 

Table II.  Major cardiovascular risk factors 103 patients reoperated on for bleeding following open heart surgery in Iceland 2000-2005 (number of patients and % in parenthesis except for EuroSCORE where mean with standard deviation and range are indicated.

Hypertension	41 (39.8)
Hyperlipidemia	53 (51.5)
Diabetes mellitus	22 (21.4)
Body Mass Index (BMI)	26.3 ± 3.9 (18.6 – 4.,7)
Chronic obstructive lung disease (COPD)*	19 (18.4)
Renal insufficiency (preop.)	4 (3.9)
NYHA**  class III+IV	88 (85.4)
EuroSCORE	6.1 ± 3.6 (0–17)
3 vessel CAD***	63 (61.2)
Left main stenosis	38 (36.9)
Ejection fraction (EF)≤ 30%	8 (7.8)
History of heart disease
Myocardial infarction	26 (25.2)
Arrythmia	19 (18.4)
Valvular disease	7 (6.8)
Heart failure	3 (2.9)
PCI ± stent	14 (13.6)/6 (5.8)
Previous cardiac operation	7 (6.8)

*COPD = Chronic obstructive pulmonary disease, **NYHA = New York Heart Association,

*** CAD = coronary artery disease

 

 

 

 

Table III.    Preoperative use of antiplatelet and anticoagulation therapy within 5 days prior to cardiac surgery for 103 patients that were reoperated on for bleeding following open heart surgery in Iceland 2000-2005. Patients could be taking more than one drug simultaneously (number of patients and % in parenthesis).

 

High-dose LMWH*	36 (35)
Aspirin	28 (27.2)
Clopidogrel	8 (7.8)
Clopidogrel + aspirin	5 (4.9)
Warfarin	4 (3.9)

*low molecular weight heparin

 

 

 

Table IV.   Operation-related factors for 103 patients reoperated on for bleeding following open heart surgery in Iceland 2000-2005 (mean, standard deviation and range).

Urgent/emergency operation (%)	7 (6.8)
Number of distal anastomoses	3.2 ± 1.1 (1 -5)
Intraoperative bleeding (ml)	3237 ± 5150 ( 350 – 35330)
Operative time (skin-to-skin) (min)	268 ± 145 (115 – 930)
Perfusion time (min)	130 ± 75 (48 – 536)
Aortic cross-clamp time (min)	78 ± 49) (22 – 284)

 

 

 

 

Table V.  Amount of bleeding within 24 hrs. following the primary operation and the amount of blood products administered (mean, standard deviaton and range).

 

Bleeding (ml)	3943 ± 2168 (690 – 10740)
Packed red cells (units)	16,5 ± 14,7 (2-88)
Plasma (units)	15,6 ±16,1 (0-73)
Thrombocytes (sets)	2,3 ± 2,4 (0-13)

 

 

 

 

Table VI.  Postoperative complications following open heart surgery in Iceland 2000-2005. Patients can have more than one complication (number of patients and % in parenthesis).

 

Atrial arrhytmias	60 (58.3)
Pleural effusion requiring drainage	25 (24.3)
Myocardial infarction	24 (23.3)
Urinary tract infection	11 (10.7)
Pneumonia	9 (8.7)
Sternal dehiscence	7 (6.8)
Stroke	4 (3.9)
Adult respiratory distress syndrome	3 (2.9)
Sternal wound infection*	12 (11.7)
Wound infection following saphenectomy**	3 (5)

*one case of mediastinitis **  Those who were diagnosed during hospital stay.

 

Table VII.   Information on 16 patients that died within 30 days after reoperation for bleeding following open heart surgery in Iceland 2000-2005.

M= males, F=females, CABG = Coronary Artery Bypass Graft, OPCAB = Off-Pump Coronary Artery Bypass, AVR = Aortic Valve Replacement, PCR = Packed Red Cells, * information missing

 

 

 

 

Table VIII.     Comparison of reoperation-rate for bleeding after open heart surgery in different studies.

Study (year)	No. of patients	Rate of reoperation for bleeding  (%)
Choong et al. (2007) 10	3220	5.9
Wolfe et al. (2007) 12	2148	4.9
Karthik et al.(2004) 9	2898	3.1
Hall et al.(2001) 6	2263	3.6
Dacey et al.(1998) 11	8586	3.6
Moulton et al.(1996) 8	6015	4.2
Unsworth-White et al.(1995) 7	2221	3.8
Present study (2009)	1295	8

 

 

Figure 1.        Percentage of patients that were reoperated on for bleeding in Iceland 2000-2005, according to the time from the primary operation until the reoperation was started. Six patients were information was missing were excluded.Alltogether 87% patients were operated on within 12hours from the primary operation.