Adoption of Lung Protective ventilation IN patients undergoing Emergency laparotomy: the ALPINE study. A prospective multicentre observational study.

BACKGROUND: Emergency abdominal surgery is associated with a high risk of postoperative pulmonary complications (PPCs). The primary aim of this study was to determine whether patients undergoing emergency laparotomy are ventilated using a lung-protective ventilation strategy employing tidal volume ≤8 ml kg-1 ideal body weight-1, PEEP >5 cm H2O, and recruitment manoeuvres. The secondary aim was to investigate the association between ventilation factors (lung-protective ventilation strategy, intraoperative FiO2, and peak inspiratory pressure) and the occurrence of PPCs. METHODS: Data were collected prospectively in 28 hospitals across London as part of routine National Emergency Laparotomy Audit (NELA). Patients were followed for 7 days. Complications were defined according to the European Perioperative Clinical Outcome definition. RESULTS: Data were collected from 568 patients. The median [inter-quartile range (IQR)] tidal volume observed was 500 ml (450-540 ml), corresponding to a median tidal volume of 8 ml kg-1 ideal body weight-1 (IQR: 7.2-9.1 ml). A lung-protective ventilation strategy was employed in 4.9% (28/568) of patients, and was not protective against the occurrence of PPCs in the multivariable analysis (hazard ratio=1.06; P=0.69). Peak inspiratory pressure of <30 cm H2O was protective against development of PPCs (hazard ratio=0.46; confidence interval: 0.30-0.72; P=0.001). Median FiO2 was 0.5 (IQR: 0.44-0.53), and an increase in FiO2 by 5% increased the risk of developing a PPC by 8% (2.6-14.1%; P=0.008). CONCLUSIONS: Both intraoperative peak inspiratory pressure and FiO2 are independent factors significantly associated with development of a postoperative pulmonary complication in emergency laparotomy patients. Further studies are required to identify causality and to demonstrate if their manipulation could lead to better clinical outcomes.

Haemodynamic monitoring in the peri-operative period: the past, the present and the future.

Over recent years there has been an increase in the implementation of goal-directed therapy using minimally invasive haemodynamic monitoring techniques to guide peri-operative care. Since the introduction of the pulmonary artery flotation catheter in the 1980s, various haemodynamic monitors have been developed, each associated with their own benefits and limitations. Goal-directed therapy has been well-established as a standard of care in the peri-operative period and has largely been associated with a reduction in morbidity and mortality. However, evidence over the last few years from major studies has led us to question: what is the future for goal-directed therapy? Care of the peri-operative patient has significantly evolved over the last decade and this needs to be taken into account when assessing the results of these studies. We should therefore not look at the effects of goal-directed therapy in isolation but as part of a progressive care bundle. Additionally, other markers of haemodynamic status have also begun to be further appreciated and these are worthy of further investigation. We feel that the future for haemodynamic monitoring remains promising with new areas of interest continuously emerging, but further research is still required.