A QASM January 2023 (Volume 3) Anticoagulation and the older surgical patient Data from the Queensland Audit of Surgical Mortality (QASM) shows that a high percentage of patients (age 65 or older) had haemorrhages as a consequence of anticoagulation. A QASM assessor stated: 'Charting of anticoagulant medication around the time of surgery should be meticulously detailed regarding timing and dosage. Simply writing "withhold perioperatively" on the medical chart and writing "chemical VTE prophylaxis from tomorrow" without making changes to the medication chart creates an environment for errors.' This QASM perspective presents data for Queensland patients with recorded haemorrhage and anticoagulant treatment who died in hospital (QASM patients) or who were discharged from acute public and private hospitals (Queensland Hospital Admitted Patient Data Collection - QPHADC). Haemorrhage includes subarachnoid, intracerebral and non-traumatic intracranial haemorrhage, cerebral infarction and stroke. The dataset also included patients with cerebral haemorrhage occurring after a fall.
BACKGROUND
Anticoagulant use is increasing as the population ages and general practitioners (GPs) prescribe anticoagulant treatment more frequently to combat potential consequences of cardiac, intracranial or mesenteric thrombosis.1,2 Anticoagulant treatment for stroke prevention and coronary artery disease has improved but unexpected consequences can arise in several conditions, particularly in elderly patients.2 These include intracranial bleeds and mesenteric arterial disease with bowel ischaemia. Anticoagulant treatment may interact with other drugs as well as antimicrobial therapy.3-5 Side-effects of anticoagulant treatment interactions increase coagulopathy and create postoperative crises including haematomas and postoperative bleeds.3-5 Failure to review and recognise a patient’s anticoagulation status prior to surgery can result in postoperative haemorrhage.6 Drug-induced coagulopathy can also result in intracranial bleeds after a fall.7
QUEENSLAND PATIENTS (1 January 2017–31 December 2021)
The number of Queensland patients who were admitted overnight to acute public and private hospitals, and who had haemorrhage and anticoagulant treatment noted in their medical records, was accessed from QHAPDC. The dataset comprised 1,797 patients with 3,256 episodes of care. Haemorrhage in the context of anticoagulant treatment occurred in approximately 0.06% of QHAPDC episodes of care (i.e. 1,797 of approximately 2,984,250 episodes of care during the period January 2017 to Dec 2021). In 73.0% of episodes of care (1,311/1,797) involving haemorrhage and anticoagulant treatment, the patient was age 65 or older.
QASM PATIENTS (1 January 2017–31 December 2021)
QASM reviewed 5,351 in-hospital deaths and determined that 14.7% of these patients had haemorrhage while taking anticoagulant treatment (786/5,351). Most patients with haemorrhage while taking anticoagulant treatment were admitted to the following specialties: General Surgery, Orthopaedics, Neurosurgery or Cardiothoracic Surgery, and were age 65 or older (73.9%; 581/786) (Table 1). For those age 65 or older, patients admitted to Orthopaedics, Vascular Surgery, Urology and Plastic/Reconstructive Surgery were more likely to experience haemorrhage as a consequence of anticoagulant treatment compared to General Surgery. For those age younger than 65, Cardiothoracic Surgery patients were more likely to experience haemorrhage as a consequence of anticoagulant treatment compared to General Surgery patients.
Table 1. Patients with haemorrhage while taking anticoagulant treatment by surgical specialty and age group Surgical speciality# General Surgery (n = 289) Orthopaedic Surgery (n = 136)
Age group <65 yrs n = 205 (26.1%)
Odds ratio (95% CI) <65 yrs
Age group 65+ yrs n = 581 (73.9%)
Odds ratio (95% CI) 65+yrs
27.7%
Reference
72.3%
Reference
9.6%
0.35 (0.20 to 0.60)*
90.4%
1.25 (1.14 to 2.05)*
Neurosurgery (n = 126)
33.3%
1.20 (0.88 to 1.64)
66.7%
0.92 (0.80 to 1.06)
Cardiothoracic Surgery (n = 110)
42.7%
1.54 (1.16 to 2.05)*
57.3%
0.79 (0.66 to 0.94)*
Vascular Surgery (n = 70)
15.7%
0.57 (0.32 to 1.01)
84.3%
1.17 (1.03 to 1.32)*
Urology (n = 34) Paediatric Surgery (n = 9) Otolaryngology Head and Neck Surgery (n = 6)
2.9%
0.16 (0.16 to 0.74)*
97.1%
1.34 (1.22 to 1.47)*
100.0%
3.61 (3.00 to 4.35)*
0.0%
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33.3%
1.20 (0.38 to 3.79)
66.7%
0.92 (0.52 to 1.63)
#Excludes any surgical specialties with 5 or less patients (i.e. oral/maxillofacial surgery and plastic and reconstructive surgery); numbers too low to calculate and patients would be identifiable. *Statistically significant at 95% confidence interval (CI). The odds ratio is used to report the strength of association between an exposure (i.e. surgical specialty) and an outcome (i.e. haemorrhage while taking anticoagulant treatment). It is the ratio of the odds of the outcome happening in one surgical specialty versus the reference group (General Surgery). The larger the odds ratio, the stronger the association. The smaller the odds ratio, the less likely the event is to be found with exposure. If the 95% CI for the odds ratio includes 1, then the odds ratio did not reach statistical significance.