The definition of myocardial infarction follows the 4th universal definition

An acute episode of neurological dysfunction consistent with an ischemic or hemorrhagic cause. For the diagnosis of stroke, the following criteria must be fulfilled: a) rapid onset of a focal/global neurologic deficit with at least one of the following: change in level of consciousness, hemiplegia, hemiparesis, numbness or sensory loss affecting one side of the body, dysphagia/aphasia, hemianopia, amaurosis, or other new neurological signs/symptoms consistent with stroke; b) the duration of a focal/global neurologic deficit is at least 24 hours, OR the neurological deficit results in death, OR there is neuroimaging evidence of a new infarct/ hemorrhage; and c) there is no other readily identifiable non-stroke cause for the clinical presentation (e.g., brain tumor, trauma, infection, hypoglycemia, peripheral lesion).

Proximal VTE includes pulmonary embolism or proximal deep vein thrombosis.

The diagnosis of proximal deep venous thrombosis requires:

Thrombosis involving the popliteal vein or more proximal veins for leg DVT or axillary or more proximal veins for arm DVTs.

Any of the following defines evidence of vein thrombosis:

A persistent intraluminal filling defect on contrast venography (including on computed tomography), Noncompressibility of one or more venous segments on B mode compression ultrasonography, or a clearly defined intraluminal filling defect on doppler imaging in a vein that cannot have compressibility assessed (e.g., iliac, inferior vena cava, subclavian).

The diagnosis requires symptoms and any one of the following:

1. a high probability ventilation/perfusion lung scan,
2. an intraluminal filling defect of segmental or larger artery on a helical CT scan,
3. an intraluminal filling defect on pulmonary angiography, or
4. a positive diagnostic test for DVT (e.g., positive compression ultrasound) and one of the following:

i) non-diagnostic (i.e., low or intermediate probability) ventilation/perfusion lung scan, or ii) non-diagnostic (i.e., subsegmental defects or technically inadequate study) helical CT scan

Increase in serum creatinine concentration from the preoperative (pre-enrollment) concentration by either an increase of ≥26.5 μmol/L (≥0.3 mg/dL) within 48 hours of surgery or an increase of 50% or greater within 7 days of surgery.

New acute renal failure resulting in use of a hemodialysis machine or peritoneal dialysis apparatus

Acute Heart Failure is defined as a clinical sign (i.e., at least one of the following: elevated jugular venous pressure, respiratory rales/crackles, crepitations, or presence of S3) and at least one of the following:

1. Radiographic findings (i.e., at least one of the following: vascular redistribution, interstitial pulmonary edema, frank alveolar pulmonary edema, or multiple and diffuse bilateral B lines on ultrasonography);
2. Elevated levels of natriuretic peptides; or
3. Heart failure treatment implemented with diuretics with documented clinical improvement.

The definition of clinically important atrial fibrillation requires the documentation of atrial fibrillation of any duration on an ECG or rhythm strip, which results in angina, congestive heart failure, symptomatic hypotension, or requires treatment with a rate controlling drug, antiarrhythmic drug, or electrical cardioversion.

Successful resuscitation from either documented or presumed ventricular fibrillation, sustained ventricular tachycardia, asystole, or pulseless electrical activity requiring cardiopulmonary resuscitation, pharmacological therapy, or cardiac defibrillation.

Life-threatening bleeding is bleeding that is fatal or leads to: significant hypotension that requires inotrope or vasopressor therapy, or urgent (within 24 hours) surgery (other than superficial vascular repair).

A critical organ bleeding event is bleeding that was intracranial, intraocular, intraspinal, pericardial, retroperitoneal, or intramuscular with compartment syndrome.

The investigators will consider a peripheral arterial thrombosis to have occurred where there is clear evidence of abrupt occlusion of a peripheral artery (i.e., not a stroke, myocardial infarction, or pulmonary embolism) consistent with either an acute local thrombotic event or a peripheral arterial embolism. To fulfill this definition, the investigators require at least one of the following objective findings of peripheral arterial thrombosis:

1. Surgical report indicating evidence of arterial thrombosis/ peripheral arterial embolism;
2. Pathological specimen demonstrating arterial thrombosis/ peripheral arterial embolism;
3. Imaging evidence consistent with arterial thrombosis/ peripheral arterial embolism; or
4. Autopsy reports documenting arterial thrombosis/ peripheral arterial embolism

Any amputation procedure, or auto amputation after the initial surgery.

For the diagnosis of delirium any one of the following criteria is required:

1. Patient meets the criteria for delirium on any in-person delirium assessment based on the Confusion Assessment Method (CAM) or any of its operationalizations (e.g., 3D-CAM, CAM-ICU); OR
2. Positive history of delirium based on the review of hospital health records.

An acute infection of the pulmonary parenchyma that is associated with at least one sign or symptom of lower respiratory acute infection (e.g., cough, pleuritic chest pain) or acute systemic illness (e.g., fever, chills, confusion, hypoxemia); accompanied by the presence of an acute infiltrate/consolidation on a chest radiograph or auscultatory findings consistent with pneumonia (such as crackles and/or localized rales) for which there is no other explanation.

An infection that involves the skin, subcutaneous tissue of the incision (superficial incisional), or the deep soft tissue (e.g., fascia, muscle) of the incision (deep incisional).

An infection that involves the urinary tract.

Physician diagnosis of functional obstruction of the gastrointestinal tract in the absence of an alternative diagnosis that leads to postoperative decreased bowel activity. The definition requires the following criteria:

1. inability to pass flatus or stool for >24 hours; and
2. persistence of one or more of the following signs and symptoms for >24h (abdominal distention; diffuse abdominal pain; or nausea or vomiting.

Fall from standing height or walking

A composite outcome of hospital re-admission and emergency department visit, which includes urgent-care centre visit.

Visit to an emergency department, which includes urgent-care centre visits.

Admission to acute care hospital after initial discharge from hospital for index surgery.

The Third International Consensus Definitions Task Force defines sepsis as a "life-threatening organ dysfunction due to a dysregulated host response to infection." Based on the Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3) criteria, sepsis will require a quick Sequential Organ Failure Assessment (qSOFA) Score ≥2 points due to infection. The qSOFA includes the following items and scoring system:

1. Glasgow Coma Scale (GCS) score of 13 or less (1 point),
2. systolic blood pressure of 100 mm Hg or less (1 point), and
3. respiratory rate of 22 breaths/min or more (1 point).

Pathologic process caused by the invasion of normally sterile tissue or fluid or body cavity by pathogenic or potentially pathogenic organisms.