Specialist commentator comments

Comments on this technology were invited from clinical specialists working in the field and relevant patient organisations. The comments received are individual opinions and do not represent NICE's view.

No commentators had used SuperNO2VA before, however all commentators were familiar with the principles of the technology.

Level of innovation

All commentators thought that SuperNO2VA was innovative. One commentator noted that it is a new development of an established treatment modality, with the novel aspect being its ability to deliver positive-pressure ventilation through a nasal continuous positive airway pressure (CPAP) mask which up until now has been able to offer CPAP only. Another commentator highlighted that it allows oral cavity access for procedures such as oesophagoscopy and oral intubation, it can be used with an anaesthesia machine or oxygen cylinder (without the need for additional equipment or CPAP machine), it can be used to give CPAP perioperatively to any patient needing CPAP or when sedation has been administered, and that it could be specifically useful when patients are identified at preoperative assessment to have obstructive sleep apnoea, but that there is no additional time available for further evaluation or for starting CPAP treatment. A different commentator suggested it was innovative in offering a cost-effective way of delivering CPAP for those patients who are not already on CPAP. Current alternatives identified by commentators were nasal oxygen delivery devices, however these devices need additional equipment. A different commentator highlighted that patients with their own CPAP machine are encouraged to bring this in for use in the perioperative setting.

Potential patient impact

Potential patient benefits identified by commentators included providing oxygen during the entire perioperative period, delivering CPAP when patients forget to bring their own CPAP machine, and preventing airway collapse. Particular patients who may benefit from this technology include patients with obstructive sleep apnoea, morbid obesity and patients having deep sedation. Another commentator identified benefits for patients in high dependency and intensive care units having close monitoring, in the operating theatre as part of general anaesthesia equipment (for use in supervised operative procedures by trained anaesthetists), and also in the recovery room for patients with obstructive sleep apnoea or those with neuromuscular diseases recovering from sedation or anaesthesia.

However, risks if used by non-experts were also highlighted. Patients may be over-sedated into the territory of needing general anaesthesia, leading to a risk of gastric aspiration, hypoventilation and desaturation. Other concerns related to the risk of gastric insufflation and aspiration if oxygen was applied at too high a pressure. The same commentator identified that effectiveness would be reduced if the mouth was left open, for example, during a dental or ear, nose and throat procedure, because of entrained gas leaking out of the mouth, resulting in hypoventilation and hypoxaemia.

Potential system impact

One commentator stated that SuperNO2VA may result in shorter stays for outpatient procedures (such as endoscopy or transoesophageal echocardiography) in patients who would normally need intubation under general anaesthesia. It may also allow patients with obstructive sleep apnoea to have procedures under sedation without intubation. However, this places these patients at risk of airway aspiration, which they would not be exposed to with intubation. The commentator concluded that the device must be used in carefully selected patients and by expert anaesthetists only. Two other commentators did not think that SuperNO2VA would result in substantial changes in the patient pathway, outcomes, or length of hospital stay. One of the commentators cited lack of evidence to back up outcomes. Another commentator thought that the most important affect is from clinicians being aware of the potential for airway obstruction. The same commentator thought that it was a cheap and accessible way to deliver CPAP in the perioperative period and patients most able to benefit could be those in the post-anaesthesia care unit who may be able to be discharged back to the ward earlier.

Commentators estimated that costs would likely be similar to current options, with a measurable cost benefit unlikely. However, 1 commentator identified that current practice for patients who do not have their own CPAP device needs sophisticated apparatus with much more expensive masks. The need for a full cost analysis was emphasised. Two commentators agreed that SuperNO2VA would be in addition to standard care and not a replacement, whereas another commentator was unable to state this because of the lack of evidence.

General comments

Commentators identified that training for anaesthetists, operating department practitioners and recovery nurses would be needed to use the device and to troubleshoot problems with the interface or seal. One commentator thought that the training would be rapidly achieved, but that the same level of monitoring as for general anaesthesia would be needed. Safety concerns highlighted were that the device must only be used in appropriate patients, is not a replacement for invasive ventilation, and is not appropriate when endotracheal intubation and ventilation is needed. A different commentator highlighted that there may be pressure exerted on clinicians to do procedures currently done on an inpatient basis in outpatient settings. For this reason, very specific patient pathways must be developed including case selection, procedure selection, minimal standards for recovery and access to high dependency units to ensure that SuperNO2VA is used safely. A further concern related to resource burden in the outpatient setting. More expert trained theatre staff and access to a postoperative recovery room would be needed because of patients known to be higher risk having outpatient rather than inpatient procedures.

The eligible population was estimated by 1 commentator as 10% of the target population. Other commentators estimated that 5% of women, 10% of men and 20% to 40% of patients with morbid obesity also have obstructive sleep apnoea and could benefit from nasal CPAP.

Highlighted practical issues with SuperNO2VA included the need to ensure the mask is well-fitted to make sure that there is no leak. Adoption issues were identified by 2 commentators, naming cost, lack of staffing in outpatients and lack of patient pathways as barriers. All commentators stated that further research is needed. Suggested research included a sham study, a comparative study comparing SuperNO2VA with standard techniques (nasal oxygenation and non-invasive ventilation) in patients who are morbidly obese or have obstructive sleep apnoea, and more clinical trials to show safety around aspiration risk and showing improved oxygenation.