Prehabilitation

Main components:

medical optimisation
physical exercise
nutritional support
psychological support

1 MET = 3.5ml/kg/min

2 FOS = 4 MET = 14ml/kg/min consumption

VO2 peak same concept as MET (∴ same unit)

AT: when ↑VCO2 rate > ↑VO2 rate

AT >11ml/kg/min

CPET

VO2 peak: cardiopulmonary function
AT: muscle bulk

6MWT & DASI most c/w CPET (used if no $ )

DASI:
limitation: not validated in Chinese population

modified DASI = 5 Qs
modified DASI 4 = 5 Qs - sexual relation

DASI cutoff = 34
modified DASI cutoff = 2

Pre-op modifiable risks

multimodal prehabilitation

definition of prehab: enhancing the functional capacity of a person to withstand a stressful event

resilience
response
recovery

6MWT: 20m = clinically significant

implication of JAMA paper: prehab may be useful if

6MWT <400m
age >60yo

Nutrition:
MST: malnutrition screening tool

immunonutrition: benefit in major surgery

Functional capacity:
ASA: historical reason → out of favour

SORT:

UK cohort
may not apply locally

POSSUM: may not useful pre-op

NSQIP

US cohort
update yearly w/ data

Prehab limitation: e.g. travelling, delaying OT, cost (e.g. CPET)

frailty is not an illness, but a syndrome that combines the effects of natural ageing with the outcomes of multiple long-term conditions, and a loss of fitness, strength, and physiological reserves

The fact that multimodal interventions have a greater magnitude of effect than individual interventions exemplifies the marginal gains theory, popularised in the sport of cycling and advocated in aviation, business, and even healthcare

References

Tutorial by Henry

Prehabilitation High-Quality Evidence Is Still Required - BJA