Applications of Nasal High-Flow Oxygen Therapy in Critically ill Adult Patients

High-flow nasal cannula oxygen therapy during anesthesia recovery for older orthopedic surgery patients: A prospective randomized controlled trial

BACKGROUND

Hypoxemia is a common complication in older patients during postoperative recovery and can cause pulmonary complications. Therefore, reducing the incidence of postoperative hypoxemia is a clinical concern.

AIM

To investigate the clinical efficacy of high-flow nasal cannula oxygen (HFNCO) in the resuscitation period of older orthopedic patients.

METHODS

In this prospective randomized controlled trial, 60 older patients who underwent orthopedic surgery under general anesthesia were randomly divided into two groups: those who used conventional face mask and those who used HFNCO. All patients were treated with 60% oxygen for 1 h after extubation. Patients in the conventional face mask group were treated with a combination of air (2 L) and oxygen (2 L) using a traditional mask, whereas those in the HFNCO group were treated with HFNCO at a constant temperature of 34 °C and flow rate of 40 L/min. We assessed the effectiveness of oxygen therapy by monitoring the patients’ arterial blood gas, peripheral oxygen saturation, and postoperative complications.

RESULTS

The characteristics of the patients were comparable between the groups. One hour after extubation, patients in HFNCO group had a significantly higher arterial partial pressure of oxygen (paO₂) than that of patients in conventional face mask group (P < 0.001). At extubation and 1 h after extubation, patients in both groups showed a significantly higher arterial partial pressure of carbon dioxide (paCO₂) than the baseline levels (P < 0.001). There were no differences in the saturation of peripheral oxygen, paO₂, and paCO₂ between the groups before anesthesia and before extubation (P > 0.05). There were statistically significant differences in paO₂ between the two groups before anesthesia and 1 h after extubation and immediately after extubation and 1 h after extubation (P < 0.001). However, there were no significant differences in the oxygen tolerance score before leaving the room, airway humidification, and pulmonary complications 3 d after surgery between the two groups (P > 0.05).

CONCLUSION

HFNCO can improve oxygen partial pressure and respiratory function in elderly patients undergoing orthopedic surgery under general endotracheal anesthesia. Thus, HFNCO can be used to prevent postoperative hypoxemia.

Efficacy and safety of nasal high-flow oxygen in COPD patients

Background

Nasal high-flow oxygen therapy (HFOT) is a novel treatment option for patients suffering from acute or chronic respiratory failure. Aim of our study was to compare safety and efficacy of HFOT with those of conventional oxygen treatment (COT) in normo- and hypercapnic COPD patients.

Methods

A single cohort of 77 clinically stable hypoxemic patients with an indication for long-term oxygen treatment (LTOT) with or without hypercapnia successively received COT and HFOT for 60 min each, including oxygen adaption and separated by a 30 min washout phase.

Results

HFOT was well-tolerated in all patients. A significant decrease in PaCO₂ was observed during oxygen adaption of HFOT, and increased PaO₂ coincided with significantly increased SpO₂ and decreased AaDO₂ during both treatment phases. Even at a flow rate of 15 L/min, oxygen requirement delivered as air mixture by HFOT tended to be lower than that of COT (2.2 L/min). Not only was no increase in static or dynamic lung volumes observed during HFOT, but even was a significant reduction of residual lung volume measured in 36 patients (28%).

Conclusions

Thus, short-term use of HFOT is safe in both normocapnic and hypercapnic COPD patients. Lower oxygen levels were effective in correcting hypoxemic respiratory failure and reducing hypercapnia, leading to a reduced amount of oxygen consumption. Long-term studies are needed to assess safety, tolerability, and clinical efficacy of HFOT.

Trial registration

ClinicalTrials.gov NCT01686893 13.09.2012 retrospectively registered (STIT-1) and NCT01693146 14.09.2012 retrospectively registered (STIT-2). Studies were approved by the local ethics committee (Ethikkommission der Medizinischen Universität Innsbruck, Studienkennzahl UN3547, Sitzungsnummer 274/4.19).

Novel therapies for perioperative respiratory complications

Postoperative respiratory complications are of paramount clinical importance as they prolong the hospitalization, increase the costs of treatment and contribute to the perioperative mortality. Obesity, preexisting pulmonary disease and advanced age are known risk factors for developing postoperative respiratory complications, which affect exceeding number of patients. Hereby, we present a review on the pathogenesis of post-operative respiratory complications particularly in obese and older patients. We further focus on the standard management and emerging therapies for the post-operative respiratory complications.