ACTA Project Grant
The efficacy of prophylactic nasal high flow oxygen compared with soft face mask oxygen therapy in improving early postoperative recovery in patients after lung resection surgery
Dr Maurice Hogan
Background: Patients who undergo surgery and have part of their lung removed are at significant risk of postoperative complications. One method of reducing the risk of lung complications is to treat patients with non-invasive ventilation or continuous positive airways pressure postoperatively. However this often requires admission to a high dependency unit or intensive care (ICU), and is uncomfortable because of the need for a tight fitting mask, as well as being labour intensive and costly. Nasal high flow oxygen is a new alternative as it provides warmed humidified oxygen at high flow, and also has been shown to assist breathing and improve recovery. It is comfortable during use and indeed may be more comfortable than standard (dry) oxygen via a facemask or nasal prongs, and it may be administered on a normal ward, however its routine use after lung surgery has not been tested before.
Methods: Adult patients who are scheduled to undergo lung surgery will be recruited with full ethical approval and informed consent. Before and after surgery, each patient will perform a 6- minute walking test under the supervision of a physiotherapist. This simple tests measures how far patients can walk in 6 minutes. Patients will thereafter undergo surgery under general anaesthesia
as they would normally. After the operation they will looked after following our enhanced recovery program, incorporating excellent pain relief, regular physiotherapy, early mobilisation and eating and drinking, and removal of chest drains and tubes as soon as possible.
On arrival in the recovery room after their surgery, patients will be randomly assigned to receive supplemental oxygen via a soft facemask (standard group), or via high-flow nasal cannulae (intervention group). Patients will be administered oxygen for at least 24 hours after surgery.
Patients who develop breathing difficulty will receive treatment based on their clinical need. On the third postoperative day they will repeat the walking test. Additionally we will compare the x-rays of patients after the operation to see if one group has more areas of lung collapse than the other group. We will also compare pain scores and the amounts of painkillers required. We will use a short questionnaire to determine if there is any difference in how patients feel they recovered before they leave hospital and how quickly they returned to normal activities after discharge, and also to evaluate how they tolerated either the facemask or high flow nasal cannulae.
Statistics: We aim to evaluate whether the use of nasal high flow oxygen post lung resection surgery can improve patients early functional outcome. We will use the walking test to determine this, because it is a measure of patients' functional ability, i.e. it represents how much they can do. It is therefore directly relevant to their recovery. We have used data from previous studies to calculate that we will need a total of 64 patients to take part in order to evaluate whether high flow nasal oxygen improves patients' early recovery after lung resection surgery, compared with standard oxygen administration via a soft face mask.
