Effects of high-flow nasal cannula in patients with mild to moderate hypercapnia: a prospective observational study

[High-flow nasal oxygen therapy and hypercapnic acute respiratory failure]

Humidified high-flow nasal oxygen therapy (HFNO) has, in recent years, come to assume a key role in the management of hypoxemic acute respiratory failure (ARF). While non-invasive ventilation (NIV) currently represents the first-line ventilatory strategy in patients exhibiting hypercapnic ARF, the operating principles and physiological effects of HFNO could be interesting and useful in the initial management of hypercapnic ARF and/or after extubation, particularly in acute exacerbations of chronic obstructive pulmonary disease. Under these conditions, HFNO could be used either alone continuously or in combination with NIV during breaks in spontaneous breathing, depending on the severity and etiology of the underlying hypercapnic ARF.

High-flow nasal cannula: Evaluation of the perceptions of various performance aspects among Chinese clinical staff and establishment of a multidimensional clinical evaluation system

Objective

In order to facilitate education for clinical users, performance aspects of the high-flow nasal cannula (HFNC) devices were evaluated in the present study. A multidimensional HFNC clinical evaluation system was established accordingly.

Materials and Methods

Clinical staff from Chinese hospitals were invited to participate in an online questionnaire survey. The questionnaire was mainly about the accuracy of temperature, flow rate, and oxygen concentration of HFNC, as well as its humidification capacity. We also investigated how the clinical staff of different professions made decisions on HFNC evaluation indicators. Based on the results of the questionnaire survey of clinicians with rich experience in using HFNC, the relative weights of temperature accuracy, flow velocity accuracy, oxygen concentration accuracy, and humidification ability of HFNC equipment were calculated by the AHP to establish a clinical evaluation system. Four kinds of common HFNC devices were tested and evaluated, and the clinical performance of the four kinds of HFNC devices was evaluated by the new scoring system.

Results

A total of 356 clinicians participated in and completed the questionnaire survey. To ensure the reliability of the HFNC evaluation system, we only adopted the questionnaire results of clinicians with rich experience in using HFNCs. Data from 247 questionnaires (80 doctors, 105 nurses, and 62 respiratory therapists [RTs]) were analyzed. A total of 174 participants used HFNC more than once a week; 88.71% of RTs used HFNC ≥ 1 score daily, 62.86% of nurses used HFNC ≥ 1 score daily, and 66.25% of doctors used HFNC ≥ 1 daily. There was no significant difference in the frequency of use between doctors and nurses. Finally, the relative weights of temperature accuracy (0.088), humidification capacity (0.206), flow velocity accuracy (0.311), and oxygen concentration accuracy (0.395) in the HFNC clinical evaluation system were obtained. The relative weights of clinicians with different occupations and the frequency of HFNC use were obtained. After testing four kinds of HFNC devices through the evaluation system, it was found that the four kinds of HFNC devices have different advantages in different clinical performances, and AiRVO₂ has excellent performance with regard to temperature accuracy and humidification ability. HF-75A and NeoHiF-i7 are good at ensuring the stability of oxygen concentration and the accuracy of the flow velocity of the transported gas, while OH-80S is relatively stable in all aspects.

Conclusion

The clinical evaluation system of HFNC is based on the weight of the experience of clinical personnel with different medical backgrounds. Although the existing practitioners have different educational backgrounds (academic qualifications, majors), our evaluation system can enhance clinical staff’s awareness of HFNC and further optimize the clinical use of HFNC.

Current status of treatment of acute respiratory failure in Korea

Background: Acute respiratory failure (ARF) is one of the most common causes of intensive care unit (ICU) admission and in-hospital mortality. In South Korea, about 25% of patients admitted to the ICU require mechanical ventilation. The in-hospital mortality rate of these patients is 48%. Respiratory failure can be categorized based on pathophysiologic derangements, and the treatment options vary depending on their classification. This study discusses the status and treatment strategies of patients with ARF in Korea.Current Concepts: The most common treatment for ARF was conventional oxygen therapy, being used at least once in 7.0% of all admitted adult patients and 85.1% of patients admitted with respiratory failure. High-flow oxygen therapy was required in 1.4% of all admissions and 17.2% of respiratory failure-related admissions. High-flow oxygen therapy was attempted in 19.1% of patients who needed invasive mechanical ventilation. Non-invasive positive pressure ventilation (NIV) was used in 0.4% of all admissions and 5.1% of respiratory failure-related admissions. Hypercapnic respiratory failure (57.1%) was the most common reason for NIV use. Invasive mechanical ventilation was required in 2.8% of all admissions and 33.8% of respiratory failure-related admissions.Discussion and Conclusion: Despite its clinical significance, no large-scale studies have been performed on the etiology, treatment, and prognosis of patients with ARF in South Korea. A multicenter or a Korean National Health Insurance Service database study is necessary to accurately identify the characteristics, diagnose problems, and develop treatment guidelines for patients with ARF in South Korea.