None listed
Conditions
Brief summary
A major contributor to postoperative pulmonary complications after major surgery is collapse (atelectasis) in poorly ventilated lung segments during and after general anaesthesia (GA). Atelectasis arises from the reduced muscle tone caused by nearly all anaesthetics,and the non-physiological pattern of distribution of ventilation that characterizes controlled mechanical positive pressure ventilation (CMV), and occurs early in the course of anaesthesia. Strategies to reduce lung atelectasis and postoperative pulmonary complications include the use of positive end-expiratory pressure (PEEP) and lung recruitment manoeuvres. Recently, Maquet Critical Care AB (Sweden) have released a new functionality on their Flow-i anaesthesia machine which allows targeted lung recruitment using a stepped increase in PEEP and lung inflation pressures. The system simultaneously monitors airway pressures and dynamic lung compliance, The latter is used to identify the optimal level of PEEP to minimize lung atelectasis, where measured dynamic lung compliance (Cdyn) is maximal. We wish to measure the effectiveness of this new technology on improving lung function and gas exchange in patients under GA for elective surgery.
Interventions
Intraoperative stepped lung recruitment manoeuvre (stepped increases in PEEP [Positive End expiratory Pressure] of 5cmH2O from 0 up to 20cmH2O) using the Maquet Flow-i anaesthesia machine, applied by the anaesthetist after commencement of laparoscopic gas insufflation, with identification of optimal PEEP using monitoring of dynamic lung compliance, with continued ventilation at 6-8 mL/kg tidal volume and optimal PEEP + 2 cmH2O at a rate to mantain EtCO2 at 35-40 mmHg. Data will be logged automat
Intraoperative stepped lung recruitment manoeuvre (stepped increases in PEEP [Positive End expiratory Pressure] of 5cmH2O from 0 up to 20cmH2O) using the Maquet Flow-i anaesthesia machine, applied by the anaesthetist after commencement of laparoscopic gas insufflation, with identification of optimal PEEP using monitoring of dynamic lung compliance, with continued ventilation at 6-8 mL/kg tidal volume and optimal PEEP + 2 cmH2O at a rate to mantain EtCO2 at 35-40 mmHg. Data will be logged automatically by the Flow-i and downloaded at the end of the case.
Sponsors
Austin Health
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Prevention
Masking
Blinded (masking used) (Subject)
Eligibility
Sex/Gender
All
Age
18 Years to 85 Years
Healthy volunteers
No
Inclusion criteria
Patients undergoing elective laparoscopic bowel surgery under relaxant general anaesthesia planned to take at least 1 hour where placement of an arterial blood pressure monitoring line is considered appropriate for cardiovascular monitoring (systemic arterial blood pressure and/or cardiac output monitoring) for clinical purposes.
Exclusion criteria
Patients unable to provide informed consent Women who are pregnant Patients with cognitive impairment Patients with poor command of English. Body mass index (BMI) > 35. Impaired lung function: Patients with severely impaired respiratory function on history and examination (FEV1 TLCO or FVC < 30% predicted),
Outcome results
None listed