Prehabilitation in major abdominal surgery: risk stratification and optimising perioperative care

With the aging of the population, the incidence of abdominal tumours is also increasing. Surgery is an important treatment modality for such tumours. However, surgery is still associated with 20-30% risk of perioperative complications. This is due to several reasons. The patient's condition is an important risk factor for the development of complications. The preoperative optimisation of the patient's condition, in preparation for treatment, is called prehabilitation. There is increasing interest in prehabilitation, although it is not yet standard care. This is partly because there are still some remaining questions such as: what is the optimal training program, for whom prehabilitation is (most) suitable or necessary and whether it is cost effective. This manuscript describes studies that address these issues. One study shows that preoperative partially supervised home training has high effectiveness in improving aerobic fitness, in patients scheduled for liver or pancreas surgery for cancer. In addition to physical fitness, however, a prehabilitation program must also address other "modifiable" risk factors such as malnutrition, anaemia (due to iron deficiency), frailty, substance use (smoking/alcohol), and impaired psychological resilience (anxiety/stress). Another study shows that a prehabilitation program targeting these six factors is also estimated to have financial benefits in patients undergoing pancreatic surgery. Prehabilitation gives the most benefit in high-risk patients. Therefore, it is important to make an adequate risk stratification for each patient. Furthermore, this thesis discusses muscle loss after surgery. To improve postoperative outcomes in major abdominal surgery, muscle loss after surgery should be prevented.