Table 2.

Assessment tools: Canadian Study of Health and Ageing Clinical Frailty Scale [24] and Clavien-Dindo grading of complications according to severity of complications [25].

Canadian study of health and ageing clinical frailty scale
Index	Fitness	Definition
1	Very fit	People who are robust, active, energetic and motivated. They tend to exercise regularly and are among the fittest for their age.
2	Fit	People who have no active disease symptoms but are less fit than category 1. Often, they exercise or are very active occasionally.
3	Managing well	People whose medical problems are well controlled, even if occasionally symptomatic, but often are not regularly active beyond routine walking.
4	Very mild frailty	Previously vulnerable, this category marks early transition from complete independence. While not dependent on others for daily help, often symptoms limit activities e.g., ‘slowed up’ and/or being tired during the day.
5	Mild frailty	People who often have more evident slowing, and need help with high order instrumental activities of daily living. Typically mild frailty impairs shopping and walking outside alone, meal preparation, medications and begins to restrict light housework.
6	Moderate frailty	People who need help with all outside activities and with keeping house. Inside, they often have problems with stairs and need help with bathing and might need minimal assistance with dressing.
7	Severe frailty	Completely dependent for personal care, from whatever cause (physical or cognitive). Even so, they seem stable and not at high risk of dying (within 6-months).
8	Very severe frailty	Completely dependent for personal care and approaching end of life. Typically they could not recover even from a minor illness

The Clavien-Dindo Classification [Grades 1 and 2 are minor complications and grades ≥ 3 major complications]
Grade		Description
Grade I		Any deviation from the normal postoperative course without need for pharmacological treatment or surgical intervention. Allowed therapeutic regimens are antiemetics, antipyretics, diuretics, electrolytes, wound infection and physiotherapy.
Grade II		Pharmacological treatment other than grade I. Atrial fibrillation, atelectasis, lower respiratory tract infection and blood transfusion are included.
Grade III		Require surgical, bronchoscopic, endoscopic or radiological intervention.
	IIIa	Intervention not under general anaesthesia.
	IIIb	Intervention under general anaesthesia.
Grade IV		Life threatening complication requiring intensive care management.
	IVa	Single organ dysfunction.
	IVb	Multi organ dysfunction.
Grade V		Death of patient.