Application Of High-flow Nasal Cannula Research Articles

Perioperative use of high flow nasal cannula

High flow nasal cannula (HFNC) is an innovative oxygen therapy system that has gained increasing popularity in recent decades, particularly in the field of critical care medicine. The device provides a more constant and higher FiO2, generates low levels of PEEP, reduces dead space ventilation, and conditions the inspired gas, which collectively results in a reduction in work of breathing (WOB) and improved patient comfort. While the application of HFNC in critically ill patients is well-established and supported by a large body of evidence, studies of HFNC during the perioperative period are limited. However, the working mechanisms of HFNC align with physiological demands across various anesthetic processes. Consequently, this system could potentially serve as an alternative oxygen delivery system for surgical patients during perioperative care. In this article, we summarize the working principles and the effects provided by HFNC, review its implementation during the perioperative period, and discuss the current evidence regarding its use.

High-Flow Nasal Cannula Oxygen Therapy in the Management of Respiratory Failure: A Review.

High-flow nasal cannula (HFNC) oxygen therapy is gaining traction globally as a treatment for respiratory failure. There are several physiological benefits, and there is a growing body of evidence showing improved quality of life and patient comfort with HFNC, both in acute and home settings. Due to the increased burden of long-term respiratory conditions such as chronic obstructive pulmonary disease (COPD) on healthcare systems worldwide, the role of ward-based and post-discharge interventions in the prevention of hospital readmissions is an area of increasing interest.In this narrative review, we outline the physiological effects of HFNCand assess its applications in both the hospital andhome settings for acute and chronic respiratory failure. We also consider the evidence of non-invasive ventilation (NIV) versus HFNC in the hospital setting and the application of HFNC at home in stable hypercapnic respiratory failure to improve the quality of life and prevent readmissions. We also look at applications of HFNC in specific circumstances, such as the perioperative period, emergency department, and acute (mainly critical care) setting including in immunocompromised patients and palliative care.

Physiological effects of high-flow nasal cannula oxygen therapy after extubation: a randomized crossover study

BackgroundProphylactic high-flow nasal cannula (HFNC) oxygen therapy can decrease the risk of extubation failure. It is frequently used in the postextubation phase alone or in combination with noninvasive ventilation. However, its physiological effects in this setting have not been thoroughly investigated. The aim of this study was to determine comprehensively the effects of HFNC applied after extubation on respiratory effort, diaphragm activity, gas exchange, ventilation distribution, and cardiovascular biomarkers.MethodsThis was a prospective randomized crossover physiological study in critically ill patients comparing 1 h of HFNC versus 1 h of standard oxygen after extubation. The main inclusion criteria were mechanical ventilation for at least 48 h due to acute respiratory failure, and extubation after a successful spontaneous breathing trial (SBT). We measured respiratory effort through esophageal/transdiaphragmatic pressures, and diaphragm electrical activity (ΔEAdi). Lung volumes and ventilation distribution were estimated by electrical impedance tomography. Arterial and central venous blood gases were analyzed, as well as cardiac stress biomarkers.ResultsWe enrolled 22 patients (age 59 ± 17 years; 9 women) who had been intubated for 8 ± 6 days before extubation. Respiratory effort was significantly lower with HFNC than with standard oxygen therapy, as evidenced by esophageal pressure swings (5.3 [4.2–7.1] vs. 7.2 [5.6–10.3] cmH2O; p < 0.001), pressure–time product (85 [67–140] vs. 156 [114–238] cmH2O*s/min; p < 0.001) and ΔEAdi (10 [7–13] vs. 14 [9–16] µV; p = 0.022). In addition, HFNC induced increases in end-expiratory lung volume and PaO2/FiO2 ratio, decreases in respiratory rate and ventilatory ratio, while no changes were observed in systemic hemodynamics, Troponin T, or in amino-terminal pro-B-type natriuretic peptide.ConclusionsProphylactic application of HFNC after extubation provides substantial respiratory support and unloads respiratory muscles.Trial registration January 15, 2021. NCT04711759.

Acute respiratory distress after metofluthrin insecticide ingestion in a 19-month-old girl

Metofluthrin is a volatile pyrethroid insecticide. Despite being widely used as a safe household insecticide, it could cause severe systemic symptoms. A 19-month-old girl was taken to the emergency department after ingesting 1 mL of a mosquito repellent containing metofluthrin. After the arrival, the girl developed respiratory distress, which worsened progressively despite the administration of oxygen with nebulized salbutamol and budesonide. Additionally, she underwent application of high-flow nasal cannula, and administration of activated charcoal and systemic steroids. Her dyspnea gradually improved, and she was thus discharged on day 4 with oral prednisolone. All medications were discontinued 10 days after the discharge without any complication. Respiratory distress can develop after the ingestion of even a small amount of metofluthrin. Symptomatic and adjunctive steroid therapies can be effective therapeutic options.

Direct Extubation to High-Flow Nasal Cannula versus Noninvasive Ventilation in Obese Subjects.

Patients who are obese have a higher risk of acute respiratory failure after extubation in the ICU. This study aimed to compare the extubation of subjects who were critically ill and obese to high-flow nasal cannula (HFNC) versus noninvasive ventilation (NIV) to determine whether HFNC can aid in reducing postextubation respiratory failure and the re-intubation rate. In this randomized controlled trial, subjects who were obese, defined as individuals with a body mass index ≥ 30 kg/m2, were randomly assigned to receive HFNC (n = 60) versus 60 subjects treated with NIV applied immediately after extubation. The primary outcome was the incidence of postextubation respiratory failure and re-intubation rate within 72 h. Secondary outcomes included oxygenation, breathing frequency, subjective dyspnea, ICU and hospital length of stay, and ICU mortality at day 28. Compared with NIV, HFNC reduced the risk of respiratory failure by 8.4%, 95% CI 6.2-12.8%. Even though the rate of re-intubation was lower in the HFNC group versus in the NIV group, no statistical significance was observed (11.6% vs 16.6%; difference 5%, 95% CI 2.5%-8.2%). In 48-h periods and 72 h after extubation, the mean PaO2 /FIO2 significantly increased in the HFNC group compared with the NIV group. Both groups had low dyspnea levels 72 h after extubation. No difference was detected between the groups in breathing frequency. In addition, the 2 groups had no significant difference in ICU and hospital length of stay. The HFNC and NIV groups had comparable hospital mortality rates. The multivariable logistic regression analysis revealed the presence of severe obesity, comorbidities, a higher severity score, and hypercapnia remained as factors associated with an increased risk of re-intubation. Postextubation application of HFNC may prevent respiratory failure in patients who are obese. (ClinicalTrials.gov registration NCT04035351.).

Clinical features of croups caused by severe acute respiratory syndrome coronavirus 2 and by other respiratory viruses: analysis in a tertiary hospital in Jinju, Korea during the period of dominance of the Omicron variant (B.1.1.529)

Purpose: Croup is a clinical manifestation of coronavirus disease 2019 (COVID-19) in children. The Omicron variant of severe acute respiratory syndrome coronavirus 2 usually causes an upper respiratory tract infection. We investigated the differences between croups caused by COVID-19 and by other respiratory viruses (ORV).Methods: We reviewed clinical characteristics, therapeutic measures, and the Westley Croup Score of children with croup who visited the emergency department of Gyeongsang National University Hospital from January 1 through April 7, 2022. According to the laboratory-confirmed viruses, they were divided into 2 groups: COVID-19 and ORV. Between the 2 groups, we compared the abovementioned features. Moderate-to-severe croup was defined by a Westley Croup Score of 3 or higher. Results: A total of 20 children were diagnosed with croup caused by COVID-19 (n = 11; median age, 18 months) or by ORV (n = 9; 7 months). Median Westley Croup Score was higher in the COVID-19 group than in the ORV group (5.0 [range, 0-10.0] vs. 2.0 [1.0-5.0]; P = 0.031). Among the components of the scoring system, only stridor showed a significant difference (e.g., “stridor at rest”: COVID-19, 8 of 11 vs. ORV, 2 of 9; P = 0.046). Median C-reactive protein concentration was higher in the COVID-19 group (3.2 vs. 0.4 mg/L; P = 0.007). Severity of the COVID-19 group was marginally higher than that of the ORV group in terms of the median oxygen saturation (95% vs. 98%; P = 0.056) and the proportions of moderate-to-severe croup (9 of 11 vs. 3 of 9; P = 0.065) and application of high-flow nasal cannula (4 of 11 vs. 0 of 9; P = 0.094).Conclusion: Croup caused by COVID-19 during the period of dominance of the Omicron variant outbreak might be more severe than croup caused by ORV.

Comment on Liu et al. Application of High-Flow Nasal Cannula in COVID-19: A Narrative Review. Life 2022, 12, 1419.

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The Impact of High-flow Nasal Cannula vs Other Oxygen Delivery Devices during Bronchoscopy under Sedation: A Systematic Review and Meta-analyses.

The widespread diagnostic and therapeutic application of bronchoscopy is often associated with complications like desaturation. This systematic review and meta-analysis intend to scrutinize whether the high-flow nasal cannula (HFNC) is advantageous for providing respiratory support during bronchoscopic procedures under sedation, in comparison with other conventional modalities for oxygen therapy. A thorough screening of electronic databases was done till 31st December 2021 after obtaining registration in PROSPERO (CRD42021245420). Randomized controlled trials (RCT), evaluating the impact of HFNC and standard/any other oxygen-delivery devices during bronchoscopy were included in this meta-analysis. We retrieved in nine RCTs, with a total of 1306 patients, the application of HFNC during bronchoscopy led to decreased number of desaturation spells [relative risk (RR) 0.34, 95% confidence interval (CI) 0.27-0.44, I 2 = 23%], higher nadir value of SpO2 [Mean difference (MD) 4.30, 95% CI 2.41-6.19, I 2 = 96%], and improved PaO2 from baseline (MD 21.77, 95% CI 2.8-40.74, I 2 = 99%), along with similar PaCO2 values (MD -0.34, 95% CI -1.82 to 1.13, I 2 = 58%) just after the procedure. However, apart from desaturation spell, the findings are significantly heterogeneous. In subgroup analysis, HFNC had significantly lesser desaturation spells and better oxygenation than low-flow devices, but in comparison to noninvasive ventilation (NIV) had a lower nadir value of SpO2 with no other significant difference. High-flow nasal cannula led to greater oxygenation and prevented desaturation spells more effectively in comparison with low-flow devices like nasal cannula, venturi mask, etc., and may be considered as an alternative to NIV during bronchoscopy in certain high-risk patients. Roy A, Khanna P, Chowdhury SR, Haritha D, Sarkar S. The Impact of High-flow Nasal Cannula vs Other Oxygen Delivery Devices during Bronchoscopy under Sedation: A Systematic Review and Meta-analyses. Indian J Crit Care Med 2022;26(10):1131-1140.

263. EFFECTS OF PREHABILITATION AND POST-OPERATIVE HIGH-FLOW NASAL CANNULA AFTER OPEN ESOPHAGECTOMY ON PULMONARY COMPLICATIONS: A FEASIBILITY STUDY

Abstract Pulmonary complications (PPC) are still reported in 30% of patients also after minimally-invasive esophagectomy in high volume centers. 1–2. Prehabilitation programs are promising in ERAS protocols. 3 Open esophagectomy (OE) has the lowest anastomotic leakage rate but higher PPC.4,5. The combination of pre-habilitation and the application of High-Flow Nasal Cannula (HFNC) after OE has not been investigated yet. This is a feasibility study evaluating a pre-habilitation program and the post-operative application of HFNC on PPC after OE. We prospectively included patients undergoing OE from May 2021 to February 2022. A preoperative multimodal prehabilitation program was applied to all patients. Within 4 hours after surgery, patients were extubated and put under HFNC (50–60 lt/min with FIO2 0.4, humidifier temperature at 34°C) for the following 5 days. Chest physiotherapist applied daily post-operative respiratory exercise to all patients. Hospital stay outcomes, feasibility of HFNC and PPC were recorded by 30 days after surgery. We compared this group with an historic cohort (January 2016–March 2021) where HFNC was not applied to determine differences in baseline characteristics and post-operative complications. We included 45 patients for the final analysis, 12 in the HFNC and 33 in the historic cohort. Baseline characteristics comparisons are shown in table 1. No interruption of post-operative HFNC was recorded due to patient’s complain. PPC in the two groups were statistically comparable. No adverse event was related to HFNC application. The overall leakage rate was 9%. A prehabilitation program and HFNC use after OE seems feasible, safe and well tolerated by patients. PPC were lower in the treatment group without statistically significant difference. Pneumonia was recorded in less than 20% of patients; in the study group there weren’t severe pulmonary complications (ARDS, reintubations). HFNC looks like an interesting tool for post-operative respiratory support. Larger randomized controlled trials should be designed to evaluate HFNC efficacy after esophagectomy.

Application of High-Flow Nasal Cannula in COVID-19: A Narrative Review.

Background: During the first wave of COVID-19, the large influx of severely ill patients led to insufficient availability of beds in intensive care units and a shortage of ventilators. The shortage of ventilators, high mortality of intubated patients, and high risk of infections among healthcare workers involved in intubation were the main factors that led to the prevalence of noninvasive respiratory support during the pandemic. The high-flow nasal cannula (HFNC) is a commonly used, popular form of noninvasive respiratory support. Due to its unique physiological effects, HFNC can provide a high fraction of humidified oxygen and is satisfactorily comfortable for patients with COVID-19. However, before the COVID-19 era, there was little evidence on the application of HFNC in patients with acute respiratory failure caused by viral infection. Aim: This narrative review provides an overview of recent studies on the use of HFNC in patients with COVID-19-related acute hypoxemic respiratory failure. The main topics discussed include the probability of successful use of HFNC in these patients, whether late intubation increases mortality, the availability of convenient and accurate monitoring tools, comparison of HFNC with other types of noninvasive respiratory support, whether HFNC combined with the prone position is more clinically useful, and strategies to further reduce the infection risk associated with HFNC. The implication of this study is to identify some of the limitations and research gaps of the current literature and to give some advice for future research.

High flow nasal cannula for patients undergoing bronchoscopy and gastrointestinal endoscopy: A systematic review and meta-analysis.

BackgroundHigh flow nasal cannula is gaining increasingly used in patients undergoing endoscopic procedures. We undertook this systematic review and meta-analysis to determine whether high flow nasal cannula (HFNC) could effectively minimize the risk of hypoxemia as compared with conventional oxygen therapy (COT).MethodsWe performed a comprehensive search of Pubmed, Cochrane Central Register of Controlled Trials (CENTRAL), Embase, and Web of Science. Studies involving the application of HFNC during endoscopic procedures were identified.ResultsWe included 15 randomized controlled trials (7 bronchoscopy, 8 gastrointestinal endoscopy). Patients receiving HFNC during endoscopic procedures had a significantly lower risk of hypoxemia (defined as SpO2 < 90%) versus COT group (risk ratio = 0.32; 95%CI (0.22–0.47), 13 studies, 4,093 patients, moderate-quality evidence, I2 = 48.82%, P < 0.001). The lowest SpO2 was significantly higher in HFNC group (mean difference = 4.41; 95%CI (2.95–5.86), 9 studies, 1,449 patients, moderate-quality evidence, I2 = 81.17%, P < 0.001) than those receiving COT. No significant difference was detected between groups in end-procedure partial pressure of CO2 (standard mean difference = −0.18; 95%CI (−0.52–0.15), 5 studies, 238 patients, moderate-quality evidence, I2 = 42.25%, P = 0.29). Patients receiving HFNC were associated a lower need for airway intervention (risk ratio = 0.45; 95%CI (0.24–0.84), 8 studies, 2,872 patients, moderate-quality evidence, I2 = 85.97%, P = 0.01) and less procedure interruption (risk ratio = 0.36; 95%CI (0.26–0.51), 6 studies, 1,562 patients, moderate-quality evidence, I2 = 0.00%, P < 0.001). The overall intubation rate after endoscopy was 0.20% in both group, with no difference detected (risk ratio = 1.00; 95%CI (0.30–3.35), 7 studies, 2,943 patients, low-quality evidence, I2 = 0.00%, P = 1.00).ConclusionThis systematic review and meta-analysis found moderate to low evidence that the application of HFNC was associated with improved oxygenation, decreased need for airway intervention, and reduced procedure interruption in patients undergoing endoscopic procedures. Future larger sample and high-quality studies are warranted to confirm our result and further investigate the effectiveness of HFNC in patients at risk. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/, identifier: CRD42022298032.

Unusual complications of non-invasive mechanical ventilation (NIV) and high-flow nasal cannula (HFNC): A systematic review.

The first application of modern non-invasive mechanical ventilation (NIV) can be traced back to over 30 years ago when a patient suffering from Duchenne Muscular Dystrophy was successfully ventilated. Since then, the use of NIV has been on the rise throughout the world. Although a very modern and safe therapy, complications during its application are inevitable. In addition to some well-known complications, others have described more rare entities. In this article, we described such rare complications as pneumoperitoneum, pneumocephalus, parotitis, gastric perforation, and barotrauma. The purpose of this review was to describe unusual complications of NIV, their prevalence, and the mechanisms by which such complications arise. We performed a clinical review by searching PubMed, Embase, and Cochrane libraries with Mesh terms: 'non-invasive mechanical ventilation', 'high-flow nasal cannula', 'rare complication', 'unusual complication', and 'unexpected complication'. These terms were cross-referenced with other keywords: 'pneumoperitoneum', 'parotitis', 'pneumocephalus', 'gastric insufflation', and 'barotrauma'. We included 26 research papers. When applying mechanical ventilation, it is necessary to have a strong knowledge of the mechanics of the device as well as familiarity with the complications that may occur during its use, including less common ones. Prompt and effective treatment of such complications is required, as well as careful consideration of the potential causes of such events, during the application of NIV or HFNC.

Noninvasive ventilation and high-flow nasal cannula in patients with acute hypoxemic respiratory failure by covid-19: A retrospective study of the feasibility, safety and outcomes

BackgroundNoninvasive ventilation (NIV) and High-flow nasal cannula (HFNC) are the main forms of treatment for acute respiratory failure. This study aimed to evaluate the effect, safety, and applicability of the NIV and HFNC in patients with acute hypoxemic respiratory failure (AHRF) caused by COVID-19. MethodsIn this retrospective study, we monitored the effect of NIV and HFNC on the SpO2 and respiratory rate before, during, and after treatment, length of stay, rates of endotracheal intubation, and mortality in patients with AHRF caused by COVID-19. Additionally, data regarding RT-PCR from physiotherapists who were directly involved in assisting COVID-19 patients and non−COVID-19. Results62.2 % of patients were treated with HFNC. ROX index increased during and after NIV and HFNC treatment (P < 0.05). SpO2 increased during NIV treatment (P < 0.05), but was not maintained after treatment (P = 0.17). In addition, there was no difference in the respiratory rate during or after the NIV (P = 0.95) or HFNC (P = 0.60) treatment. The mortality rate was 35.7 % for NIV vs 21.4 % for HFNC (P = 0.45), while the total endotracheal intubation rate was 57.1 % for NIV vs 69.6 % for HFNC (P = 0.49). Two adverse events occurred during treatment with NIV and eight occurred during treatment with HFNC. There was no difference in the physiotherapists who tested positive for SARS−COV-2 directly involved in assisting COVID-19 patients and non−COVID-19 ones (P = 0.81). ConclusionThe application of NIV and HFNC in the critical care unit is feasible and associated with favorable outcomes. In addition, there was no increase in the infection of physiotherapists with SARS-CoV-2.

Application Evaluation of High-Flow Humidified Oxygen in Patients with Respiratory Failure after General Anesthesia Extubation for Multiple Injuries.

Objective To explore the effect of high-flow humidified oxygen therapy (HFNC) on patients with respiratory failure after general anesthesia extubation for multiple injuries. Methods 214 patients with multiple injuries in our hospital who underwent general anesthesia and suffered respiratory failure after weaning extubation and received sequential treatment were included. And, they were divided into control group (HFNC group) and observation group (NIMV group) according to the random number table method. Patients in the control group (125 cases) used high-flow nasal cannula (HFNC) after general anesthesia extubation, while patients in the observation group (89 cases) used NIMV. The respiratory rate, heart rate, finger pulse oxygen, oxygenation index (PaO2/FiO2), and re-tracheal intubation rate in the two groups were compared at 2, 8, and 24 hours after sequential treatment, and the mortality rate and hospital stay of ICU time were whole-course observation. And, the effect of conventional oxygen inhalation or HFNC on oxygenation and prognosis was analyzed. Then, SPSS21.0 software was applied for statistical analysis. To analyze the effect of conventional oxygen inhalation or HFNC on the improvement of oxygenation and prognosis, the receiver operating characteristic (ROC) curve can be used to evaluate the feasibility and treatment effect of high-flow nasal oxygen therapy (HFNC) for patients with respiratory failure after general anesthesia extubation for multiple injuries. Results Compared with the NIMV group, the respiratory frequency and heart rate of the HFNC group were significantly improved after 2 h, 8 h, and 24 h. At the same time, the finger pulse oxygen and oxygenation index increased significantly and returned to normal levels. HFNC can significantly reduce the reintubation rate, ICU hospital stay, and mortality rate. The area under the ROC curve was 0.9102, with 95% CI (0.8256, 0.9949) and P < 0.0001. Conclusion For patients with multiple injuries undergoing general anesthesia and respiratory failure after weaning and extubation, the application of HFNC can moderate patients' heart rate and respiratory rate faster, increase oxygenation index and finger pulse oxygen, and reduce the reintubation rate, mortality rate, and ICU stay. At the same time, it can effectively improve the respiratory failure of patients after extubation and reduce the occurrence of complications.

Impact of initial flow rate of high-flow nasal cannula on clinical outcomes in infants with bronchiolitis.

Bronchiolitis is a common condition in the paediatric population. Severe cases often receive respiratory support with high-flow nasal cannula (HFNC). Significant variation in the application of HFNC exists throughout Australia and internationally. This study aimed to determine if the flow rate used initially and when ceasing HFNC at the end of the illness alters clinical outcomes. A retrospective analysis was conducted of 251 children less than 12 months of age when admitted to the Women's and Children's Hospital Adelaide with bronchiolitis requiring HFNC therapy between the period of April 2016 to April 2019. The primary outcome was to determine if commencing HFNC therapy at different rates (1 L/kg/min, 1.5L/kg/min and 2L/kg/min) affected length of stay or treatment failure (escalation in physiological parameters or respiratory support). Treatment failure occurred in 33%, 13% and 26% of those starting at 1L/kg/min, 1.5L/kg/min and 2L/kg/min, respectively. Commencing HFNC therapy at 1L/kg/min increased length of stay by an average of 30 h (P < 0.001) and the likelihood of treatment failure (P < 0.002) compared with starting at 1.5L/kg/min. There was no statistical difference in outcomes between starting at 1.5L/kg/min and 2L/kg/min. There was no significant difference in the length of stay from the starting of weaning HFNC to time of discharge. The commencing flow rates of initial HFNC therapy impact individual patient's outcomes, including length of stay and rates of treatment failure. Clinicians should consider commencing HFNC at 1.5L/kg/min or 2L/kg/min in infants that have failed low-flow oxygen therapy.

Effects of high flow nasal cannula on exercise endurance in patients with chronic obstructive pulmonary disease

Ventilation limitation has a significant adverse effects on cardiovascular function and tissue oxygenation during exercise in patients with chronic obstructive pulmonary disease (COPD). High flow nasal cannula (HFNC) improve ventilation by washing out the anatomical dead space and providing oxygen at constant concentration. This study aimed to examine the effects of HFNC on the exercise performance and hemodynamic status in COPD patients. Fifteen patients with COPD performed two constant load exercise tests (CLET) at the 70% of maximum workload achieved at a previous incremental exercise test on arm ergometer. The CLET were performed with HFNC and with nasal cannula (NC) in random order. The hemodynamics parameters of subjects during exercises were measured by a bioelectrical impedance device. The tissue oxygenation status (oxygenated hemoglobin, deoxygenated hemoglobin (hHb), total hemoglobin) was measured by a near infrared spectrophotometer. The exercise duration was longer for HFNC test than NC test (962.9 ± 281.7 s, vs 823.9 ± 184.9 s, p< 0.05). At the end of CLET, the PetCO2 was lower for HFNC than NC (29.3±5.1mmHg vs 32.1±5.5mmHg, p<0.05). There was no difference in cardiac output (NC: 7.5±1.8 vs HFNC: 7.4±3.0L,p>0.05), stroke volume (NC:73.5±21.0 vs HFNC 67.5±16.3ml, p>0.05). The changes of hHb in muscle tissues was significantly lower in HFNC test than that in NC test (p<0.05). HFNC resulted in a significant decrease in CO2 production and increase in exercise duration. The application of HFNC may improve the efficiency of exercise training by allowing patients to sustain exercise for longer time.

Quality Initiative to Reduce High-Flow Nasal Cannula Duration and Length of Stay in Bronchiolitis

High-flow nasal cannula (HFNC) use in bronchiolitis may prolong length of stay (LOS) if weaned more slowly than medically indicated. We aimed to reduce HFNC length of treatment (LOT) and inpatient LOS by 12 hours in 0- to 18-month-old patients with bronchiolitis on the pediatric hospital medicine service. After identifying key drivers of slow weaning, we recruited a multidisciplinary "Wean Team" to provide education and influence provider weaning practices. We then implemented a respiratory therapist-driven weaning protocol with supportive sociotechnical interventions (huddles, standardized orders, simplification of protocol) to reduce LOT and LOS and promote sustainability. In total, 283 patients were included: 105 during the baseline period and 178 during the intervention period. LOT and LOS control charts revealed special cause variation at the start of the intervention period; mean LOT decreased from 48.2 to 31.2 hours and mean LOS decreased from 84.3 to 60.9 hours. LOT and LOS were less variable in the intervention period compared with the baseline period. There was no increase in PICU transfers or 72-hour return or readmission rates. We reduced HFNC LOT by 17 hours and LOS by 23 hours for patients with bronchiolitis via multidisciplinary collaboration, education, and a respiratory therapist-driven weaning protocol with supportive interventions. Future steps will focus on more judicious application of HFNC in bronchiolitis.

Efficacy of high flow nasal oxygen therapy in children with acute respiratory failure

Objective: To investigate the efficacy of high flow nasal cannula (HFNC) in children with acute respiratory failure. Methods: A prospective study was conducted. A total of 153 patients aged from 1 to 14 years with acute respiratory failure were enrolled, who were admitted to pediatric intensive care unit (PICU) of Shanghai Children's Hospital from January 2018 to December 2019. HFNC success was defined as no need for invasive mechanical ventilation and successfully withdrawn from HFNC, while HFNC failure was defined as need for invasive mechanical ventilation. HFNC at a flow rate of 2 L/(kg·min) (maximum ≤ 60 L/min) with inhaled oxygen concentration (FiO2) between 0.30 and 1.00 was applied to maintain percutaneous oxygen saturation (SpO2) of 0.94-0.97. Parameters including arterial partial pressure of oxygen (PaO2), partial pressure of carbon dioxide in artery (PaCO2), SpO2 and PaO2/FiO2 were collected before and during the application of HFNC at 1 h, 6 h, 12 h, 24 h and 48 h, as well as over 48 h after HFNC withdrawn. Comparison between the groups was performed by student t test, Mann-Whitney U test or chi-square test. The sensitivity and specificity of the above parameters in predicting HFNC success were evaluated by receiver operating characteristic (ROC) curve. Results: A total of 153 children (70 males and 83 females) were enrolled. Among them, 131 (85.6%) cases were successfully weaned off from HFNC and 22 (14.4%) failed. The duration of HFNC was 57 (38, 95) hours in the successful group, and the PaO2/FiO2 before HFNC application and after HFNC was withdrawn were 187 (170, 212) mmHg (1 mmHg=0.133 kPa) and 280 (262, 292) mmHg, respectively. The duration of HFNC in the failure group was 19 (9, 49) hours, and the PaO2/FiO2 before HFNC application and after HFNC withdrawn were 176 (171, 189) mmHg and 159 (156, 161) mmHg, respectively. The values of PaO2/FiO2 were significantly higher in the successful group than those in the failed group at using HFNC initially 1 h (196 (182, 211) vs. 174 (160, 178) mmHg, Z =-5.105, P<0.01), 6 h (213 (203, 220) vs. 168 (157, 170) mmHg, Z =-6.772, P<0.01), 12 h (226 (180, 261) vs. 165 (161, 170) mmHg, Z =-4.308, P<0.01), 24 h (229 (195, 259) vs. 165 (161, 170) mmHg, Z=-4.609, P<0.01) and 48 h (249 (216, 273) vs. 163 (158, 169) mmHg, Z =-4.628, P<0.01) after the HFNC application, and over 48 h after HFNC was withdrawn (277 (268, 283) vs. 157 (154, 158) mmHg, Z=-3.512, P<0.01). Moreover, the PaO2 levels were significantly higher in the successful group than those in the failed group using HFNC initially at 1 h (73.7 (71.0, 76.7) vs. 70.0 (66.2, 71.2) mmHg, Z=-4.587, P<0.01) and 6 h (79.0 (75.0, 82.0) vs. 71.0 (62.0, 72.0) mmHg, Z=-5.954, P<0.01) after HFNC application. Also, the SpO2 levels showed the same differences at 1 h (0.96 (0.95, 0.96) vs. 0.94 (0.92, 0.94), Z =-4.812, P<0.01) and 6 h (0.96 (0.95, 0.97) vs. 0.94(0.91, 0.95), Z=-5.024, P<0.01) after HFNC application. Forty eight hours after HFNC was withdrawn, the PaO2 (88.0 (81.7, 95.0) vs. 63.7 (63.3, 66.0) mmHg, Z =-3.032, P<0.01) and SpO2 (0.96 (0.94, 0.98) vs. 0.91 (0.90, 0.92), Z=-3.957, P<0.01) were also significantly higher in the successful group. Regarding the HFNC complications, there was one case with atelectasis and one with pneumothorax in the failure group. HFNC was used as sequential oxygen therapy after extubation in 79 children, successful in all. ROC curve showed that the area under curve of PaO2/FiO2 in predicting HFNC success was 0.990, and the optimal cut-off value was 232 mmHg with the 95%CI of 0.970-1.000 (P<0.01). Conclusions: HFNC could be used as a respiratory support strategy for children with mild to moderate respiratory failure and as a sequential oxygen therapy after extubation. The PaO2/FiO2 when HFNC withdrow is the optimal index to evaluate the success of HFNC application.

The successful application of high-flow nasal cannula for a patient who underwent vertebroplasty with severe pulmonary hypertension

The successful application of high-flow nasal cannula for a patient who underwent vertebroplasty with severe pulmonary hypertension