This is a single centre, prospective, non-randomised clinical investigation to be undertaken at the Queen Elizabeth Hospital, Edgbaston, Birmingham.

The clinical investigation will collect fully anonymised perioperative blood pressure data from patients undergoing elective high risk surgery.

The Sponsor of this clinical investigation, Directed Systems Limited, is developing a new medical device, BP Assist, which provides guidance to anaesthetists in relation to the real-time management of patient cardiovascular physiology.

This clinical investigation is designed to collect fully anonymised perioperative blood pressure data from patients undergoing high risk surgical procedures.

It is increasingly being recognised that in high risk surgery, the perioperative incidence and duration of hypotensive episodes (MAP <60mmHg) can adversely impact postoperative outcome.

Collecting continuous perioperative blood pressure data will enable hypotensive episodes to be recorded. Such data will be used to aid the development and testing of algorithms involved in generating the guidance provided by BP Assist.

Inclusion Criteria:

• Male or female, 18 years of age or older; undergoiing elective high risk surgery

Exclusion Criteria:

• <18 years of age

Patients undergoing elective high risk surgery at Queen Elizabeth Hospital, Birmingham, UK.