Abstract
Background
There is a lack of information on the independent preoperative predictors of perioperative mortality, including the influence of previous stroke and acute coronary syndromes (myocardial infarction + unstable angina, ACS). Previous studies have grouped variables under the umbrella term “ischaemic heart disease”. In this study, we investigated the influence of vascular risk factors separately.
Methods
The Hospital Episode Statistics database was analyzed for elective admissions for total hip (THR) and total knee (TKR) replacements between 2004 and 2009. Independent preoperative predictors of perioperative outcome were identified from admission secondary diagnosis codes. Perioperative mortality was defined as 30-day in-hospital death. Logistic regression analysis was used to identify independent predictors of 30-day mortality. Data was adjusted for age, social deprivation and Charlson co-morbidity score.
Results
414,985 THRs and TKRs were performed in the study period. There were 829 deaths within 30 days (0.2%). Previous ACS (OR: 1.73 [1.33 to 2.25]) and stroke (OR: 1.64 [1.02 to 2.65]) predicted 30-day mortality. ACS (OR: 3.81 [1.55 to 9.34]) within six months of THKR surgery was associated with increased odds of perioperative mortality. The effect of ACS persisted up to 12 months (OR: 1.99 [1.02 to 3.88]). Renal failure, liver disease, heart failure, peripheral vascular disease and non-atrial fibrillation arrhythmia also increased the odds of mortality.
Discussion
Previous stroke and ACS increase the odds of perioperative mortality, together with several other vascular risk factors. Within 12 months of ACS, risk of mortality is significantly elevated. Elective surgery should be avoided in this period.