High-flow nasal cannula in adults with acute respiratory failure and after extubation: a systematic review and meta-analysis

Standardised Critical Care Strategies Improve Outcomes Following Cytoreductive Surgery with Hyperthermic Intraperitoneal Chemotherapy in an Indian Peritoneal Malignancy Centre

Cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) is a major undertaking with profound peri-operative metabolic and haemodynamic alterations. It requires standardised protocols for immediate postoperative intensive care management to improve patient-related outcomes. A retrospective analysis of a prospectively maintained data-base of 244 patients who underwent CRS and HIPEC between June 2017 and July 2022 in our institute was done. Based on the audit, six strategies were implemented, namely, (1) dynamic multiparameter-based IVF therapy to aggressively correct the hyperlactatemia, (2) initiation of IV 20% human albumin infusion from POD-0, (3) correction of serum iCa2+ levels, (4) initiation of diuresis from POD-1, (5) prophylactic use of HFNO immediately post-extubation and (6) serum procalcitonin level-based empiric escalation of IV antibiotics. Patients were divided into two cohorts, pre-protocol group of 145 patients (from June 2017 to December 2020) and post-protocol group comprising of 99 patients (from January 2021 to July 2022), and were analysed for compliance and patient-related outcomes. Implementation of these strategies improved the patient-related outcomes among the two cohorts with significant reduction of Clavien-Dindo grade III/IV complications and improvement in failure to rescue (FTR) index (p < 0.05). There was highly significant reduction in median ICU and hospital stay among the two cohorts (p < 0.001). The formulated protocols of management strategies especially multiparameter-based dynamic fluid therapy, planned diuresis and prophylactic HFNO have improved the outcomes in our patients undergoing CRS and HIPEC.

Assessing swallowing disorders in adults on high-flow nasal cannula in critical and non-critical care settings. A scoping review protocol

INTRODUCTION

The high-flow nasal cannula (HFNC) has become a widely used respiratory support system, which has proven to be effective in different populations. The facilitation of oral communication and feeding have been described as advantages of this support. Nevertheless, swallowing disorders associated with the use of HFNC have been postulated. However, such evidence is scattered in the literature, not systematically searched, and needs to be adequately summarised. This review aimed to explore the literature, to identify and map the evidence, regarding the frequency and methods of assessment of swallowing disorders in adult HFNC users, in both critical and non-critical units.

MATERIALS AND METHODS

A scoping review will be conducted. A systematic search in MEDLINE (Ovid), Embase (Ovid), CENTRAL, CINAHL (EBSCOhost), and other resources will be conducted. Primary studies, in any language or publication status, assessing the incidence of swallowing disorders in adults with HFNC support will be included. Two reviewers will independently select studies and extract data. Disagreements will be resolved by consensus or a third reviewer. The results will be reported narratively, using tables and figures to support them.

DISCUSSION

Positive end-expiratory pressure generated in the airway by HFNC could impair the proper swallowing performance. Knowing the methodological characteristics, the instruments or scales used to assess the presence of dysphagia, and the results of the studies may contribute to considering swallowing assessment in this population on a routine basis, as well as to guide the conduct of new studies that may respond to less researched areas in this topic.

REGISTRATION

Registration number: INPLASY2022110078.

An Analysis of the Effect of Noninvasive Positive Pressure Ventilation on Patients with Respiratory Failure Complicated by Diabetes Mellitus

Objective

To observe the clinical effectiveness of noninvasive positive pressure ventilation in patients with respiratory failure complicated by diabetes.

Methods

From May 2021 to May 2022, 90 patients with respiratory failure complicated by diabetes treated in our hospital were recruited and randomly assigned to receive either medication (control group) or noninvasive positive pressure ventilation (study group), with 45 patients in each group. The clinical endpoint was therapeutic outcomes.

Results

Noninvasive positive pressure ventilation resulted in significantly lower Self-Rating Anxiety Scale (SAS) and Self-Rating Depression Scale (SDS) scores versus medications (P < 0.05). Patients with noninvasive positive pressure ventilation showed better pulmonary function indices versus those with medications (P > 0.05). There was no significant difference in arterial oxygen (PaO₂), carbon dioxide partial pressure (PaCO₂), and arterial oxygen pressure/inspired fraction of O₂ (PaO₂/FiO₂) between the two groups prior to the intervention (P > 0.05). However, patients in the study group had significantly elevated PaO₂ and PaO₂/FiO₂ and lower PaCO₂ levels than those in the control group (P < 0.05). Following the intervention, noninvasive positive pressure ventilation resulted in significantly lower inflammatory factor levels versus medications (P > 0.05). After the intervention, markedly better glucose control was observed in the study group versus the control group (P < 0.05). The incidence of complications in the control group was 2.38%, which was significantly lower than that of the control group (16.67) (P < 0.05).

Conclusion

Noninvasive positive pressure ventilation effectively suppresses the inflammatory response, improves the blood gas analysis index, and eliminates the negative emotions of patients, thereby maintaining hemodynamic stability and improving clinical efficacy with a better safety profile. Further studies are recommended prior to clinical promotion.

Efficacy of preventive use of oxygen therapy after planned extubation in high-risk patients with extubation failure: A network meta-analysis of randomized controlled trials

Background

Extubation failure is common in critically ill patients, especially those with high-risk factors, and is associated with poor prognosis. Prophylactic use of oxygen therapy after extubation has been gradually introduced. However, the best respiratory support method is still unclear.

Purpose

This study aimed to evaluate the efficacy of four post-extubation respiratory support approaches in reducing reintubation and respiratory failure in patients at high-risk of extubation failure.

Methods

A comprehensive search was performed in Cochrane Central Register of Controlled Trials, PubMed, EMBASE, and Web of Science from inception to June 2022. Randomized controlled trials (RCTs) comparing post-extubation preventive use of respiratory management strategies, including conventional oxygen therapy (COT), non-invasive ventilation (NIV), and high-flow nasal catheter (HFNC) in high-risk patients with extubation failure were reviewed. Primary outcomes were reintubation rate and respiratory failure. Secondary outcomes included intensive care unit (ICU) mortality, ICU stay and length of hospital stay (LOS).

Results

Seventeen RCTs comprising 2813 participants were enrolled. Compared with COT, the three respiratory support methods (NIV, HFNC, NIV + HFNC) were all effective in preventing reintubation [odds ratio (OR) 0.46, 95% confidence interval (CI) 0.32–0.67; OR 0.26, 95% CI 0.14–0.48; OR 0.62, 95% CI 0.39–0.97, respectively] and respiratory failure (OR 0.23, 95% CI 0.10–0.52; OR 0.15, 95% CI 0.04–0.60; OR 0.26, 95% CI 0.10–0.72, respectively). NIV and NIV + HFNC also reduced ICU mortality (OR 0.40, 95% CI 0.22–0.74; OR 0.32, 95% CI 0.12–0.85). NIV + HFNC ranked best in terms of reintubation rate, respiratory failure and ICU mortality based on the surface under the cumulative ranking curve (SUCRA) (99.3, 87.1, 88.2, respectively). Although there was no significant difference in shortening ICU stay and LOS among the four methods, HFNC ranked first based on the SUCRA.

Conclusion

Preventive use of NIV + HFNC after scheduled extubation is probably the most effective respiratory support method for preventing reintubation, respiratory failure and ICU death in high-risk patients with extubation failure. HFNC alone seems to be the best method to shorten ICU stay and LOS.

Systematic review registration

[https://www.crd.york.ac.uk/prospero/], identifier [CRD42022340623].

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.

Prediction Model of Extubation Outcomes in Critically Ill Patients: A Multicenter Prospective Cohort Study

Liberation from mechanical ventilation is of great importance owing to related complications from extended ventilation time. In this prospective multicenter study, we aimed to construct a versatile model for predicting extubation outcomes in critical care settings using obtainable physiological predictors. The study included patients who had been extubated after a successful 30 min spontaneous breathing trial (SBT). A multivariable logistic regression model was constructed to predict extubation outcomes (successful extubation without reintubation and uneventful extubation without reintubation or noninvasive respiratory support) using eight parameters: age, heart failure, respiratory disease, rapid shallow breathing index (RSBI), PaO2/FIO2, Glasgow Coma Scale score, fluid balance, and endotracheal suctioning episodes. Of 499 patients, 453 (90.8%) and 328 (65.7%) achieved successful and uneventful extubation, respectively. The areas under the curve for successful and uneventful extubation in the novel prediction model were 0.69 (95% confidence interval (CI), 0.62−0.77) and 0.70 (95% CI, 0.65−0.74), respectively, which were significantly higher than those in the conventional model solely using RSBI (0.58 (95% CI, 0.50−0.66) and 0.54 (95% CI, 0.49−0.60), p = 0.004 and <0.001, respectively). The model was validated using a bootstrap method, and an online application was developed for automatic calculation. Our model, which is based on a combination of generally obtainable parameters, established an accessible method for predicting extubation outcomes after a successful SBT.

The Respiratory Rate-Oxygenation Index predicts failure of post-extubation high-flow nasal cannula therapy in intensive care unit patients: a retrospective cohort study

Objective

To investigate the applicability of the Respiratory Rate-Oxygenation Index to identify the risk of high-flow nasal cannula failure in post-extubation pneumonia patients.

Methods

This was a 2-year retrospective observational study conducted in a reference hospital in Bogotá, Colombia. All patients in whom post-extubation high-flow nasal cannula therapy was used as a bridge to extubation were included in the study. The Respiratory Rate-Oxygenation Index was calculated to assess the risk of post-extubation high-flow nasal cannula failure.

Results

A total of 162 patients were included in the study. Of these, 23.5% developed high-flow nasal cannula failure. The Respiratory Rate-Oxygenation Index was significantly lower in patients who had high-flow nasal cannula failure [median (IQR): 10.0 (7.7 - 14.4) versus 12.6 (10.1 - 15.6); p = 0.006]. Respiratory Rate-Oxygenation Index > 4.88 showed a crude OR of 0.23 (95%CI 0.17 - 0.30) and an adjusted OR of 0.89 (95%CI 0.81 - 0.98) stratified by severity and comorbidity. After logistic regression analysis, the Respiratory Rate-Oxygenation Index had an adjusted OR of 0.90 (95%CI 0.82 - 0.98; p = 0.026). The area under the Receiver Operating Characteristic curve for extubation failure was 0.64 (95%CI 0.53 - 0.75; p = 0.06). The Respiratory Rate-Oxygenation Index did not show differences between patients who survived and those who died during the intensive care unit stay.

Conclusion

The Respiratory Rate-Oxygenation Index is an accessible tool to identify patients at risk of failing high-flow nasal cannula post-extubation treatment. Prospective studies are needed to broaden the utility in this scenario.

A Multifaceted Extubation Protocol to Reduce Reintubation Rates in the Surgical ICU

BACKGROUND

Reintubation is associated with significant morbidity and mortality. The reintubation rate in surgical ICUs (SICUs) is ∼10% nationally but was 17.0% in our SICU. The objective of this study was to determine if the reintubation rate could be reduced with a protocol for extubation assessment and post-extubation care consisting of standardized extubation criteria and targeted interventions for patients at high risk for reintubation.

METHODS

Standardized extubation criteria for all SICU patients were identified via literature review and best-practice guidelines. High reintubation risk criteria were identified (age ≥ 65 years, chronic cardiopulmonary disease, ≥ 4 days intubated, emergency intubation, and fluid balance ≥ 5 liters) through a literature review and 13-month retrospective review of reintubations in our institution's SICU. Patients meeting at least one criterion putting them at higher risk for reintubation received interventions including post-extubation high-flow nasal cannula for 24 hours and algorithm-guided respiratory therapy.

RESULTS

During the 12-month period following protocol implementation, 36 of 402 extubations resulted in reintubations (9.0% vs. 17.0% preintervention, p < 0.001). Among all extubations, 305 (75.9%) were identified as high risk. Among reintubated patients, 34 (94.4%) met high-risk criteria. The mortality rate for reintubated patients was 40.0%, compared to 3.3% in those not reintubated (p < 0.001). The high-risk screening tool had a negative predictive value of 98%.

CONCLUSION

A multifaceted and pragmatic extubation and post-extubation care protocol significantly reduced one SICU's reintubation rate. This protocol can be easily implemented in any SICU to improve patient outcomes following extubation.

Noninvasive ventilation versus conventional oxygen therapy after extubation failure in high-risk patients in an intensive care unit: a pragmatic clinical trial

Objetivo

Determinar la efectividad de la ventilación no invasiva frente a oxigenoterapia convencional en pacientes con insuficiencia respiratoria aguda tras fracaso de la extubación.

Métodos

Ensayo clínico pragmático realizado una unidad de cuidados intensivos de marzo de 2009 a septiembre de 2016. Se incluyeron pacientes sometidos a ventilación mecánica > 24 horas, y que desarrollaron insuficiencia respiratoria aguda tras extubación programada, siendo asignados a ventilación no invasiva u oxigenoterapia convencional. El objetivo primario fue reducir la tasa de reintubación. Los objetivos secundarios fueron: mejora de los parámetros respiratorios, reducción de las complicaciones, de la duración de la ventilación mecánica, de la estancia en unidad de cuidados intensivos y hospitalaria, así como de la mortalidad en unidad de cuidados intensivos, hospitalaria y a los 90 días. También se analizaron los factores relacionados con la reintubación.

Resultados

De un total de 2.574 pacientes, se analizaron 77 (38 en el grupo de ventilación no invasiva y 39 en el grupo de oxigenoterapia convencional). La ventilación no invasiva redujo la frecuencia respiratoria y cardíaca más rápidamente que la oxigenoterapia convencional. La reintubación fue menor en el grupo de ventilación no invasiva [12 (32%) versus 22(56%) en grupo oxigenoterapia convencional, RR 0,58 (IC95% 0,34 - 0,97), p = 0,039], el resto de los parámetros no mostró diferencias significativas. En el análisis multivariante, la ventilación no invasiva prevenía la reintubación [OR 0,17 (IC95% 0,05 - 0,56), p = 0,004], mientras que el fracaso hepático previo a la extubación y la incapacidad para mantener vía aérea permeable predisponían a la reintubación.

Conclusión

El empleo de la ventilación no invasiva en pacientes que fracasa la extubación podría ser beneficiosa frente a la oxigenoterapia convencional.

Effects of high-flow nasal oxygen cannula versus other noninvasive ventilation in extubated patients: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVES

A systematic review and meta-analysis were performed to compare the effects of high-flow nasal oxygen cannula (HFNC) and noninvasive ventilation (NIV) in extubated patients with respiratory insufficiency.

METHODS

The Cochrane Library, PubMed, and ClinicalTrials.gov were searched from inception to 28 February 2021, to identify randomized controlled trials. The primary outcome was reintubation within 24-72 hours after a planned extubation. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated.

RESULTS

Six articles with1746 patients were included. The effect of HFNC on the reintubation rate was noninferior to that of NIV (OR = 1.11, 95% CI: 0.85-1.44). The rate of treatment failure was 20.40% with HFNC versus 20.92% with NIV; this difference was nonsignificant (OR = 0.97, 95% CI: 0.72-1.32, P = 0.85). HFNC reduced the rates of skin lesion occurrence (10.28% versus 23.82%, OR = 0.37, 95% CI: 0.26-0.53, P < 0.00001) and post-extubation respiratory failure (23.76% versus 25.56%, OR = 0.64, 95% CI: 0.46-0.88, P = 0.006), compared with NIV.

CONCLUSIONS

In extubated patients, HFNC was noninferior to NIV in the rate of reintubation and treatment failure. Compared with NIV, HFNC decreased the occurrence of skin lesions and post-extubation respiratory failure.

Severe 2019 novel coronavirus pneumonia may cause lung bullae and bronchiectasis: A case report and concise literature review

Most of the critically ill novel coronavirus 2019 pneumonia (NCP) patients progress promptly, and soon match the ARDS diagnostic criteria. When mechanical ventilation and prone position cannot reverse the fatal hypoxia—extra-corporeal-membrane-oxygenation (ECMO) will be applied as a salvage treatment if available. Here, we report a novel coronavirus 2019 pneumonia (NCP) patient, a male, 67 years old, who was treated with ECMO for 30 days. In the midst, bronchoscopy was utilized to comprehend the airway lesions and clear secretions. And computed tomography (CT) scans were performed before and after the treatment of ECMO. In the recovering phase of his disease, the patient experienced multiple times pneumothorax on both sides. Some newly developed lung bullae in the subpleural area and modest bronchiectasis were found by the CT scan. The newly developed lung bullae was the probable cause of pneumothorax. Notably, in the whole process of his illness, the serum IL-6 only had a slight elevation in the early period, there is no typical cytokine storm as that was seen in non-COVID-19 ARDS. After 3-months meticulous treatment, the patient made a full recovery and now is discharged from our hospital. Though COVID-19 may not cause typical cytokine storm, the inflammation in lung may inflict severe damage to lung. Severe NCP may cause lung bullae and bronchiectasis, making the patients hard to be weaned from mechanical ventilation or ECMO.

Effectiveness and Harms of High-Flow Nasal Oxygen for Acute Respiratory Failure: An Evidence Report for a Clinical Guideline From the American College of Physicians

BACKGROUND

Use of high-flow nasal oxygen (HFNO) for treatment of adults with acute respiratory failure (ARF) has increased.

PURPOSE

To assess HFNO versus noninvasive ventilation (NIV) or conventional oxygen therapy (COT) for ARF in hospitalized adults.

DATA SOURCES

English-language searches of MEDLINE, Embase, CINAHL, and Cochrane Library from January 2000 to July 2020; systematic review reference lists.

STUDY SELECTION

29 randomized controlled trials evaluated HFNO versus NIV (k = 11) or COT (k = 21).

DATA EXTRACTION

Data extraction by a single investigator was verified by a second, 2 investigators assessed risk of bias, and evidence certainty was determined by consensus.

DATA SYNTHESIS

Results are reported separately for HFNO versus NIV, for HFNO versus COT, and by initial or postextubation management. Compared with NIV, HFNO may reduce all-cause mortality, intubation, and hospital-acquired pneumonia and improve patient comfort in initial ARF management (low-certainty evidence) but not in postextubation management. Compared with COT, HFNO may reduce reintubation and improve patient comfort in postextubation ARF management (low-certainty evidence).

LIMITATIONS

Trials varied in populations enrolled, ARF causes, and treatment protocols. Trial design, sample size, duration of treatment and follow-up, and results reporting were often insufficient to adequately assess many outcomes. Protocols, clinician and health system training, cost, and resource use were poorly characterized.

CONCLUSION

Compared with NIV, HFNO as initial ARF management may improve several clinical outcomes. Compared with COT, HFNO as postextubation management may reduce reintubations and improve patient comfort; HFNO resulted in fewer harms than NIV or COT. Broad applicability, including required clinician and health system experience and resource use, is not well known.

PRIMARY FUNDING SOURCE

American College of Physicians. (PROSPERO: CRD42019146691).

Comparison of high-flow nasal oxygen cannula therapy versus a standard oxygen face mask in patients with hypostatic pneumonia

Objective

We assessed the clinical effects of high-flow nasal cannula (HFNC) oxygen therapy and a standard oxygen atomizer mask on the respiratory tract in patients with hypostatic pneumonia.

Methods

We included patients with hypostatic pneumonia in this retrospective cohort study. Patients were provided continuous airway humidification by continuous oxygen atomization using either an HFNC or standard oxygen mask. Arterial blood gas analysis, the dyspnea score, inflammatory-related parameters, and adverse events of patients in the two groups were compared.

Results

Fifty-five patients had HFNC delivery and 57 had a standard oxygen atomizer mask. After 7 days of treatment, patients in the HFNC group had a higher partial pressure of arterial blood oxygen/fraction of inspired oxygen ratio (268.12±28.44 vs 238.28±30.04) and lower partial pressure of arterial blood carbon dioxide (38.02±8.84 vs 49.27±7.84 mmHg) than those in the standard oxygen mask group. The dyspnea score and inflammatory-related parameters in the HFNC group were significantly lower than those in the standard oxygen mask group. The incidence of adverse events was lower in the HFNC group than in the standard oxygen mask group.

Conclusion

HFNC therapy relieves clinical symptoms more quickly than a standard oxygen mask and reduces the incidence of adverse events.

High-Flow Nasal Cannula Compared With Conventional Oxygen Therapy or Noninvasive Ventilation Immediately Postextubation: A Systematic Review and Meta-Analysis

OBJECTIVES

Reintubation after failed extubation is associated with increased mortality and longer hospital length of stay. Noninvasive oxygenation modalities may prevent reintubation. We conducted a systematic review and meta-analysis to determine the safety and efficacy of high-flow nasal cannula after extubation in critically ill adults.

DATA SOURCES

We searched MEDLINE, EMBASE, and Web of Science.

STUDY SELECTION

We included randomized controlled trials comparing high-flow nasal cannula to other noninvasive methods of oxygen delivery after extubation in critically ill adults.

DATA EXTRACTION

We included the following outcomes: reintubation, postextubation respiratory failure, mortality, use of noninvasive ventilation, ICU and hospital length of stay, complications, and comfort.

DATA SYNTHESIS

We included eight randomized controlled trials (n = 1,594 patients). Compared with conventional oxygen therapy, high-flow nasal cannula decreased reintubation (relative risk, 0.46; 95% CI, 0.30-0.70; moderate certainty) and postextubation respiratory failure (relative risk, 0.52; 95% CI, 0.30-0.91; very low certainty), but had no effect on mortality (relative risk, 0.93; 95% CI, 0.57-1.52; moderate certainty), or ICU length of stay (mean difference, 0.05 d fewer; 95% CI, 0.83 d fewer to 0.73 d more; high certainty). High-flow nasal cannula may decrease use of noninvasive ventilation (relative risk, 0.64; 95% CI, 0.34-1.22; moderate certainty) and hospital length of stay (mean difference, 0.98 d fewer; 95% CI, 2.16 d fewer to 0.21 d more; moderate certainty) compared with conventional oxygen therapy, however, certainty was limited by imprecision. Compared with noninvasive ventilation, high-flow nasal cannula had no effect on reintubation (relative risk, 1.16; 95% CI, 0.86-1.57; low certainty), mortality (relative risk, 1.12; 95% CI, 0.82-1.53; moderate certainty), or postextubation respiratory failure (relative risk, 0.82; 95% CI, 0.48-1.41; very low certainty). High-flow nasal cannula may reduce ICU length of stay (moderate certainty) and hospital length of stay (moderate certainty) compared with noninvasive ventilation.

CONCLUSIONS

High-flow nasal cannula reduces reintubation compared with conventional oxygen therapy, but not compared with noninvasive ventilation after extubation.

Association of noninvasive respiratory support with mortality and intubation rates in acute respiratory failure: a systematic review and network meta-analysis

BACKGROUND

Noninvasive respiratory support devices may reduce the tracheal intubation rate compared with conventional oxygen therapy (COT). To date, few studies have compared high-flow nasal cannula (HFNC) use with noninvasive positive-pressure ventilation (NPPV). We conducted a network meta-analysis to compare the effectiveness of three respiratory support devices in patients with acute respiratory failure.

METHODS

The Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, and Ichushi databases were searched. Studies including adults aged ≥ 16 years with acute hypoxic respiratory failure and randomized-controlled trials that compared two different oxygenation devices (COT, NPPV, or HFNC) before tracheal intubation were included. A frequentist-based approach with a multivariate random-effects meta-analysis was used. The network meta-analysis was performed using the GRADE Working Group approach. The outcomes were short-term mortality and intubation rate.

RESULTS

Among 5507 records, 27 studies (4618 patients) were included. The main cause of acute hypoxic respiratory failure was pneumonia. Compared with COT, NPPV and HFNC use tended to reduce mortality (relative risk, 0.88 and 0.93, respectively; 95% confidence intervals, 0.76-1.01 and 0.80-1.08, respectively; both low certainty) and lower the risk of endotracheal intubation (0.81 and 0.78; 0.72-0.91 and 0.68-0.89, respectively; both low certainty); however, short-term mortality or intubation rates did not differ (0.94 and 1.04, respectively; 0.78-1.15 and 0.88-1.22, respectively; both low certainty) between NPPV and HFNC use.

CONCLUSION

NPPV and HFNC use are associated with a decreased risk of endotracheal intubation; however, there are no significant differences in short-term mortality.

TRIAL REGISTRATION

PROSPERO (registration number: CRD42020139105 , 01/21/2020).

Post-extubation oxygenation strategies in acute respiratory failure: a systematic review and network meta-analysis

Background

High-flow nasal cannula oxygenation (HFNC) and noninvasive positive-pressure ventilation (NPPV) possibly decrease tracheal reintubation rates better than conventional oxygen therapy (COT); however, few large-scale studies have compared HFNC and NPPV. We conducted a network meta-analysis (NMA) to compare the effectiveness of three post-extubation respiratory support devices (HFNC, NPPV, and COT) in reducing the mortality and reintubation risk.

Methods

The Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, and Ichushi databases were searched. COT, NPPV, and HFNC use were assessed in patients who were aged ≥ 16 years, underwent invasive mechanical ventilation for > 12 h for acute respiratory failure, and were scheduled for extubation after spontaneous breathing trials. The GRADE Working Group Approach was performed using a frequentist-based approach with multivariate random-effect meta-analysis. Short-term mortality and reintubation and post-extubation respiratory failure rates were compared.

Results

After evaluating 4631 records, 15 studies and 2600 patients were included. The main cause of acute hypoxic respiratory failure was pneumonia. Although NPPV/HFNC use did not significantly lower the mortality risk (relative risk [95% confidence interval] 0.75 [0.53–1.06] and 0.92 [0.67–1.27]; low and moderate certainty, respectively), HFNC use significantly lowered the reintubation risk (0.54 [0.32–0.89]; high certainty) compared to COT use. The associations of mortality with NPPV and HFNC use with respect to either outcome did not differ significantly (short-term mortality and reintubation, relative risk [95% confidence interval] 0.81 [0.61–1.08] and 1.02 [0.53–1.97]; moderate and very low certainty, respectively).

Conclusion

NPPV or HFNC use may not reduce the risk of short-term mortality; however, they may reduce the risk of endotracheal reintubation.

Trial registration number and date of registration

PROSPERO (registration number: CRD42020139112, 01/21/2020).

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-021-03550-4.

The Impact of High-Flow Nasal Cannula Use on Patient Mortality and the Availability of Mechanical Ventilators in COVID-19

Rationale: How to provide advanced respiratory support for coronavirus disease (COVID-19) to maximize population-level survival while optimizing mechanical ventilator access is unknown.Objectives: To evaluate the use of high-flow nasal cannula for COVID-19 on population-level mortality and ventilator availability.Methods: We constructed dynamical (deterministic) simulation models of high-flow nasal cannula and mechanical ventilation use for COVID-19 in the United States. Model parameters were estimated through consensus based on published literature, local data, and experience. We had the following two outcomes: 1) cumulative number of deaths and 2) days without any available ventilators. We assessed the impact of various policies for the use of high-flow nasal cannula (with or without "early intubation") versus a scenario in which high-flow nasal cannula was unavailable.Results: The policy associated with the fewest deaths and the least time without available ventilators combined the use of high-flow nasal cannula for patients not urgently needing ventilators with the use of early mechanical ventilation for these patients when at least 10% of ventilator supply was not in use. At the national level, this strategy resulted in 10,000-40,000 fewer deaths than if high-flow nasal cannula were not available. In addition, with moderate national ventilator capacity (30,000-45,000 ventilators), this strategy led to up to 25 (11.8%) fewer days without available ventilators. For a 250-bed hospital with 100 mechanical ventilators, the availability of 13, 20, or 33 high-flow nasal cannulas prevented 81, 102, and 130 deaths, respectively.Conclusions: The use of high-flow nasal cannula coupled with early mechanical ventilation when supply is sufficient results in fewer deaths and greater ventilator availability.

Safety of changes in the use of noninvasive ventilation and high flow oxygen therapy on reintubation in a surgical intensive care unit: A retrospective cohort study

Reintubation after weaning from mechanical ventilation is relatively common and is associated with poor outcomes. Different methods to decrease the reintubation rate post extubation, including noninvasive ventilation, and more recently high-flow oxygen (HFO) therapy, have been proposed. In this study, we aimed to assess the safety of introducing HFO in the post-extubation care of intensive care unit (ICU) patients. We conducted a single-center cohort study of extubated adult patients hospitalized in a surgical ICU and previously mechanically ventilated for > 1 day. Our study consisted of two phases: Phase 1 (before the introduction of HFO from April 2015 to April 2016) and Phase P2 (after the introduction of HFO from April 2017 to April 2018). The primary endpoint was the reintubation rate within 48 hours of extubation. In total, 290 patients (median age 65 years [50–74]; 190 men [65.5%]) were included in the analysis (181 and 109 in Phases 1 and 2, respectively). The results of the post-extubation use of noninvasive methods (noninvasive ventilation and/or HFO) were not significantly different between the two phases (41 [22.7%] versus 29 [26.6%] patients; p = 0.480), however these methods were implemented earlier in Phase 2 (0 versus 4 hours; p = 0.009) and HFO was used significantly more often than noninvasive ventilation (24 [22.0%] versus 25 [13.8%] patients; p = 0.039). The need for reintubation within 48 hours post extubation was significantly lower in Phase 2 (4 [3.7%] versus 20 [11.0%] patients; p = 0.028) but was not significantly different at 7 days post extubation (10 [9.2%] versus 30 [16.6%] patients; p = 0.082). The earlier implementation of noninvasive methods and the increased use of HFO beginning in Phase 2 were safe and effective based on the reintubation rates within the first 48 hours post extubation and after 7 days.

High-flow nasal cannulae for respiratory support in adult intensive care patients

BACKGROUND

High-flow nasal cannulae (HFNC) deliver high flows of blended humidified air and oxygen via wide-bore nasal cannulae and may be useful in providing respiratory support for adults experiencing acute respiratory failure, or at risk of acute respiratory failure, in the intensive care unit (ICU). This is an update of an earlier version of the review.

OBJECTIVES

To assess the effectiveness of HFNC compared to standard oxygen therapy, or non-invasive ventilation (NIV) or non-invasive positive pressure ventilation (NIPPV), for respiratory support in adults in the ICU.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, Web of Science, and the Cochrane COVID-19 Register (17 April 2020), clinical trial registers (6 April 2020) and conducted forward and backward citation searches.

SELECTION CRITERIA

We included randomized controlled studies (RCTs) with a parallel-group or cross-over design comparing HFNC use versus other types of non-invasive respiratory support (standard oxygen therapy via nasal cannulae or mask; or NIV or NIPPV which included continuous positive airway pressure and bilevel positive airway pressure) in adults admitted to the ICU.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures as expected by Cochrane.

MAIN RESULTS

We included 31 studies (22 parallel-group and nine cross-over designs) with 5136 participants; this update included 20 new studies. Twenty-one studies compared HFNC with standard oxygen therapy, and 13 compared HFNC with NIV or NIPPV; three studies included both comparisons. We found 51 ongoing studies (estimated 12,807 participants), and 19 studies awaiting classification for which we could not ascertain study eligibility information. In 18 studies, treatment was initiated after extubation. In the remaining studies, participants were not previously mechanically ventilated. HFNC versus standard oxygen therapy HFNC may lead to less treatment failure as indicated by escalation to alternative types of oxygen therapy (risk ratio (RR) 0.62, 95% confidence interval (CI) 0.45 to 0.86; 15 studies, 3044 participants; low-certainty evidence). HFNC probably makes little or no difference in mortality when compared with standard oxygen therapy (RR 0.96, 95% CI 0.82 to 1.11; 11 studies, 2673 participants; moderate-certainty evidence). HFNC probably results in little or no difference to cases of pneumonia (RR 0.72, 95% CI 0.48 to 1.09; 4 studies, 1057 participants; moderate-certainty evidence), and we were uncertain of its effect on nasal mucosa or skin trauma (RR 3.66, 95% CI 0.43 to 31.48; 2 studies, 617 participants; very low-certainty evidence). We found low-certainty evidence that HFNC may make little or no difference to the length of ICU stay according to the type of respiratory support used (MD 0.12 days, 95% CI -0.03 to 0.27; 7 studies, 1014 participants). We are uncertain whether HFNC made any difference to the ratio of partial pressure of arterial oxygen to the fraction of inspired oxygen (PaO2/FiO2) within 24 hours of treatment (MD 10.34 mmHg, 95% CI -17.31 to 38; 5 studies, 600 participants; very low-certainty evidence). We are uncertain whether HFNC made any difference to short-term comfort (MD 0.31, 95% CI -0.60 to 1.22; 4 studies, 662 participants, very low-certainty evidence), or to long-term comfort (MD 0.59, 95% CI -2.29 to 3.47; 2 studies, 445 participants, very low-certainty evidence). HFNC versus NIV or NIPPV We found no evidence of a difference between groups in treatment failure when HFNC were used post-extubation or without prior use of mechanical ventilation (RR 0.98, 95% CI 0.78 to 1.22; 5 studies, 1758 participants; low-certainty evidence), or in-hospital mortality (RR 0.92, 95% CI 0.64 to 1.31; 5 studies, 1758 participants; low-certainty evidence). We are very uncertain about the effect of using HFNC on incidence of pneumonia (RR 0.51, 95% CI 0.17 to 1.52; 3 studies, 1750 participants; very low-certainty evidence), and HFNC may result in little or no difference to barotrauma (RR 1.15, 95% CI 0.42 to 3.14; 1 study, 830 participants; low-certainty evidence). HFNC may make little or no difference to the length of ICU stay (MD -0.72 days, 95% CI -2.85 to 1.42; 2 studies, 246 participants; low-certainty evidence). The ratio of PaO2/FiO2 may be lower up to 24 hours with HFNC use (MD -58.10 mmHg, 95% CI -71.68 to -44.51; 3 studies, 1086 participants; low-certainty evidence). We are uncertain whether HFNC improved short-term comfort when measured using comfort scores (MD 1.33, 95% CI 0.74 to 1.92; 2 studies, 258 participants) and responses to questionnaires (RR 1.30, 95% CI 1.10 to 1.53; 1 study, 168 participants); evidence for short-term comfort was very low certainty. No studies reported on nasal mucosa or skin trauma.

AUTHORS' CONCLUSIONS

HFNC may lead to less treatment failure when compared to standard oxygen therapy, but probably makes little or no difference to treatment failure when compared to NIV or NIPPV. For most other review outcomes, we found no evidence of a difference in effect. However, the evidence was often of low or very low certainty. We found a large number of ongoing studies; including these in future updates could increase the certainty or may alter the direction of these effects.

Patients With Idiopathic Pulmonary Fibrosis Admitted to the ICU With Acute Respiratory Failure-A Reevaluation of the Risk Factors and Outcomes

INTRODUCTION

Idiopathic pulmonary fibrosis (IPF) patients admitted to the ICU with acute respiratory failure (ARF) are known to have a poor prognosis. However, the majority of the studies published to date are older and had small sample sizes. Given the advances in ICU care since the publication of these studies, we sought to reevaluate the outcomes and risk factors associated with mortality in these patients.

METHODS

Retrospective study using a large multi-center ICU database. We identified 411 unique patients with IPF admitted with ARF between 2014-2015.

RESULTS

Of all IPF patients admitted to the ICU with ARF, 81.3% required mechanical ventilation (MV): 48.9% invasive and 32.4% non-invasive alone. The hospital mortality rate was 34.5% for all patients; 48.8% in patients requiring invasive MV, 21.8% in those requiring non-invasive MV and 19.5% with no MV. In multiple regression analyses, age, APACHE score, invasive MV, and hyponatremia at admission were associated with increased mortality whereas post-op status was associated with lower mortality. In patients requiring invasive MV, baseline PaO₂/FiO₂ ratio was also predictive of mortality. Non-pulmonary organ failures were present in less than 20% of the patients.

CONCLUSIONS

Although the overall mortality rate for IPF patients admitted to the ICU with ARF has improved, the mortality rates for patients requiring invasive MV remains high at approximately 50%. Older age, high APACHE score, and low baseline PaO₂/FiO₂ ratio are factors predictive of increased mortality in this population.

Energy and protein intake in critically ill people with respiratory failure treated by high-flow nasal-cannula oxygenation: An observational study

OBJECTIVES

High-flow nasal-cannula (HFNC) oxygen therapy is increasingly used in the management of respiratory distress. Since this treatment may be required for many days and may impair nutritional intake, this study planned to observe the energy and protein intake of individuals receiving this therapy.

METHODS

Forty consecutive patients requiring HFNC oxygenation after extubation or to prevent intubation from November 2017 to June 2018 were included in the study. Demographics, route of nutrition (oral, enteral, or parenteral), calories and protein prescribed and administered, and complications were noted until discharge. Statistical analysis used χ² or Kruskal-Wallis H test.

RESULTS

HFNC oxygen therapy was applied for 42 d in the 40 participants. Overall, individuals with HFNC oxygenation therapy received 449.5 (interquartile range [IQR], 312-850) kcal/d and 19.25 (IQR, 13.9-33.3) g/d protein. Twenty-one participants treated with enteral nutrition received 387 (IQR, 273-931) kcal/d and 18.5 (IQR, 13.9-33.3) g/d protein, whereas those with oral feeding (n = 13) received higher totals of calories, 600 (IQR, 459-850) kcal/d (P = 0.056), and protein, 22 (IQR, 20-45) g/d (P = 0.005). Four participants received parenteral nutrition alone, providing 543 (IQR, 375-886.5) kcal/d and 8.7 (IQR, 0-20) g/d protein. When parenteral nutrition was administered with enteral nutrition, it provided only 324 (IQR, 290-358) kcal/d. Two participants did not receive any nutritional support. The overall length of stay in the intensive care unit was 8 (IQR, 5-17.5) d. Participants receiving enteral nutrition had a longer stay (14 d; IQR, 8-20) than the oral-diet group (4 d; IQR, 2-10; P < 0.03). The rate of intubation after HFNC therapy was not significantly different between the groups (P = 0.586).

CONCLUSIONS

Administration of HFNC oxygen therapy was associated with significant underfeeding. In order to reach optimal caloric and protein intake, parenteral nutrition may be considered.

The Effectiveness of High-Flow Nasal Oxygen During the Intraoperative Period: A Systematic Review and Meta-analysis

BACKGROUND

High-flow nasal oxygen (HFNO) is increasingly being used in intensive care units for management of hypoxemia and respiratory failure. However, the effectiveness of HFNO for preventing hypoxemia in the intraoperative period is unclear. The purpose of this systematic review was to compare patient oxygenation and end-tidal CO2 (EtCO2), between HFNO and conventional oxygenation, during the intraoperative period in surgical patients.

METHODS

Standard databases were searched from inception to February 2020. Studies involving intraoperative use of HFNO with 1 of the 4 outcomes: (1) oxygen (O2) desaturation, (2) minimum O2 saturation, (3) safe apnea time, or (4) EtCO2 were included. Intraoperative period was divided into 2 phases: at induction with general anesthesia and during surgical procedure under sedation without tracheal intubation.

RESULTS

Eight randomized controlled trials (RCTs; 4 induction, 4 procedure, 2314 patients) were included for systematic review and meta-analyses. We found the risk of intraoperative O2 desaturation was lower in HFNO versus conventional oxygenation control group; at induction with an odds ratio (OR; 95% confidence interval [CI]) of 0.06 (0.01-0.59, P = .02), and during procedure, OR (95% CI) of 0.09 (0.05-0.18; P < .001). The minimum O2 saturation was higher in HFNO versus conventional oxygenation; at induction by a mean difference (MD) (95% CI) of 5.1% (3.3-6.9; P < .001), and during procedure, by a MD (95% CI) of 4.0% (1.8-6.2; P < .001). Safe apnea time at induction was longer in HFNO versus conventional oxygenation by a MD (95% CI) of 33.4 seconds (16.8-50.1; P < .001). EtCO2 at induction was not significantly different between HFNO and conventional oxygenation groups.

CONCLUSIONS

This systematic review and meta-analysis show that, in the intraoperative setting, HFNO compared to conventional oxygenation reduces the risk of O2 desaturation, increases minimum O2 saturation, and safe apnea time. HFNO should be considered for anesthesia induction and during surgical procedures under sedation without tracheal intubation in patients at higher risk of hypoxemia.

The efficacy of the WhisperFlow CPAP system versus high flow nasal cannula in patients at risk for postextubation failure: A Randomized controlled trial

PURPOSE

Compare the efficacy(reintubation rate) between a high-flow nasal cannula(HFNC) and the WhisperFlow CPAP system in patients at risk for postextubation failure.

MATERIAL AND METHODS

RCT was conducted in patients who had at least one high-risk criterion for postextubation failure. All patients were randomly assigned to CPAP or HFNC for 48 h.

RESULTS

Of 140 patients, sixty-nine were assigned to the CPAP group and 71 to the HFNC group. The reintubation rate was similar between the HFNC and WhisperFlowCPAP [5 cases(7.0%) vs. 6 cases(8.7%); P = 0.76]. The postextubation respiratory failure rate was not significantly different between the HFNC and WhisperFlow CPAP groups [10 cases(14.1%)vs.7cases(10.1%); P = 0.48]. The respiratory rate was lower in the HFNC than CPAP group(P = 0.04). The pain rating scale score was lower in the HFNC group than in the WhisperFlow CPAP group at 24 h (2.8 ± 2.0 vs. 3.7 ± 1.9, P = 0.02) and 48 h (2.8 ± 1.8 vs. 3.8 ± 1.9, P = 0.002).

CONCLUSIONS

We are unable to demonstrate a reduction in postextubation respiratory failure in at risk patients with the use of HFNC compared with the WhisperFlow CPAP system probably because small sample size, but HFNC was better tolerated.

High-flow nasal cannula for acute hypoxemic respiratory failure in patients with COVID-19: systematic reviews of effectiveness and its risks of aerosolization, dispersion, and infection transmission

PURPOSE

We conducted two World Health Organization-commissioned reviews to inform use of high-flow nasal cannula (HFNC) in patients with coronavirus disease (COVID-19). We synthesized the evidence regarding efficacy and safety (review 1), as well as risks of droplet dispersion, aerosol generation, and associated transmission (review 2) of viral products.

SOURCE

Literature searches were performed in Ovid MEDLINE, Embase, Web of Science, Chinese databases, and medRxiv. Review 1: we synthesized results from randomized-controlled trials (RCTs) comparing HFNC to conventional oxygen therapy (COT) in critically ill patients with acute hypoxemic respiratory failure. Review 2: we narratively summarized findings from studies evaluating droplet dispersion, aerosol generation, or infection transmission associated with HFNC. For both reviews, paired reviewers independently conducted screening, data extraction, and risk of bias assessment. We evaluated certainty of evidence using GRADE methodology.

PRINCIPAL FINDINGS

No eligible studies included COVID-19 patients. Review 1: 12 RCTs (n = 1,989 patients) provided low-certainty evidence that HFNC may reduce invasive ventilation (relative risk [RR], 0.85; 95% confidence interval [CI], 0.74 to 0.99) and escalation of oxygen therapy (RR, 0.71; 95% CI, 0.51 to 0.98) in patients with respiratory failure. Results provided no support for differences in mortality (moderate certainty), or in-hospital or intensive care length of stay (moderate and low certainty, respectively). Review 2: four studies evaluating droplet dispersion and three evaluating aerosol generation and dispersion provided very low certainty evidence. Two simulation studies and a crossover study showed mixed findings regarding the effect of HFNC on droplet dispersion. Although two simulation studies reported no associated increase in aerosol dispersion, one reported that higher flow rates were associated with increased regions of aerosol density.

CONCLUSIONS

High-flow nasal cannula may reduce the need for invasive ventilation and escalation of therapy compared with COT in COVID-19 patients with acute hypoxemic respiratory failure. This benefit must be balanced against the unknown risk of airborne transmission.

Preventive use of respiratory support after scheduled extubation in critically ill medical patients-a network meta-analysis of randomized controlled trials

BACKGROUND

Respiratory support has been increasingly used after extubation for the prevention of re-intubation and improvement of prognosis in critically ill medical patients. However, the optimal respiratory support method is still under debate. This network meta-analysis (NMA) aims to evaluate the comparative effectiveness of various respiratory support methods used for preventive purposes after scheduled extubation in critically ill medical patients.

METHODS

A systematic database search was performed from inception to December 19, 2019, for randomized controlled trials (RCTs) that compared a preventive use of different respiratory support methods, including conventional oxygen therapy (COT), noninvasive ventilation (NIV), high-flow oxygen therapy (HFOT), and combinational use of HFOT and NIV (HFOT+NIV), after planned extubation in adult critically ill medical patients. Study selection, data extraction, and quality assessments were performed in duplicate. The primary outcomes included re-intubation rate and short-term mortality.

RESULTS

Seventeen RCTs comprising 3341 participants with 4 comparisons were included. Compared with COT, NIV significantly reduced the re-intubation rate [risk ratio (RR) 0.55, 95% confidence interval (CI) 0.39 to 0.77; moderate quality of evidence] and short-term mortality (RR 0.66, 95% CI 0.48 to 0.91; moderate quality of evidence). Compared to COT, HFOT had a beneficial effect on the re-intubation rate (RR 0.55, 95% CI 0.35 to 0.86; moderate quality of evidence) but no effect on short-term mortality (RR 0.79, 95% CI 0.56 to 1.12; low quality of evidence). No significant difference in the re-intubation rate or short-term mortality was found among NIV, HFOT, and HFOT+NIV. The treatment rankings based on the surface under the cumulative ranking curve (SUCRA) from best to worst for re-intubation rate were HFOT+NIV (95.1%), NIV (53.4%), HFOT (51.2%), and COT (0.3%), and the rankings for short-term mortality were NIV (91.0%), HFOT (54.3%), HFOT+NIV (43.7%), and COT (11.1%). Sensitivity analyses of trials with a high risk of extubation failure for the primary outcomes indicated that the SUCRA rankings were comparable to those of the primary analysis.

CONCLUSIONS

After scheduled extubation, the preventive use of NIV is probably the most effective respiratory support method for comprehensively preventing re-intubation and short-term death in critically ill medical patients, especially those with a high risk of extubation failure.

SARS-CoV-2: minireview and review of first case in Foshan, China

The outbreak of the 2019 new coronavirus pneumonia has caught worldwide attention. Since December 2019, several pneumonia cases of unknown origin have been found in hospitals in Wuhan, Hubei Province, China. The Chinese epidemic prevention authorities have quickly organised laboratories to conduct pathogen tests on alveolar lavage fluid, throat swabs, blood and other samples by methods of virus isolation, nucleic acid testing and genome sequencing, among others. On 7 January 2020, a novel coronavirus, previously undetected in humans, was isolated and its full genome sequence was decoded [1]. On 12 January 2020, the World Health Organization (WHO) officially named this new coronavirus causing the outbreak of pneumonia in Wuhan the “2019 new coronavirus (SARS-CoV-2).”

The first case of #COVID19 in Foshan provides a reference for the treatment of severe #SARSCoV2 pneumoniahttps://bit.ly/3eD81qj

The Impact of High-Flow Nasal Cannula on the Outcome of Immunocompromised Patients with Acute Respiratory Failure: A Systematic Review and Meta-Analysis

Background and objectives: High-flow nasal cannula (HFNC) can be used as a respiratory support strategy for patients with acute respiratory failure (ARF). However, no clear evidence exists to support or oppose HFNC use in immunocompromised patients. Thus, this meta-analysis aims to assess the effects of HFNC, compared to conventional oxygen therapy (COT) and noninvasive ventilation (NIV), on the outcomes in immunocompromised patients with ARF. The Pubmed, Embase and Cochrane databases were searched up to November 2018. Materials and Methods: Only clinical studies comparing the effect of HFNC with COT or NIV for immunocompromised patients with ARF were included. The outcome included the rate of intubation, mortality and length of stay (LOS). Results: A total of eight studies involving 1433 immunocompromised patients with ARF were enrolled. The pooled analysis showed that HFNC was significantly associated with a reduced intubation rate (risk ratio (RR), 0.83; 95% confidence interval (CI), 0.74-0.94, I2 = 0%). Among subgroup analysis, HFNC was associated with a lower intubation rate than COT (RR, 0.86; 95% CI, 0.75-0.95, I2 = 0%) and NIV (RR, 0.59; 95% CI, 0.40-0.86, I2 = 0%), respectively. However, there was no significant difference between HFNC and control groups in terms of 28-day mortality (RR, 0.78; 95% CI, 0.58-1.04, I2 = 48%), and intensive care unit (ICU) mortality (RR, 0.87; 95% CI, 0.73-1.05, I2 = 57%). The ICU and hospital LOS were similar between HFNC and control groups (ICU LOS: mean difference, 0.49 days; 95% CI, -0.25-1.23, I2 = 69%; hospital LOS: mean difference, -0.12 days; 95% CI, -1.86-1.61, I2 = 64%). Conclusions: Use of HFNC may decrease the intubation rate in immunocompromised patients with ARF compared with the control group, including COT and NIV. However, HFNC could not provide additional survival benefit or shorten the LOS. Further large, randomized controlled trials are needed to confirm these findings.

Use High-Flow Nasal Cannula for Acute Respiratory Failure Patients in the Emergency Department: A Meta-Analysis Study

Objective

To evaluate the efficacy of high-flow nasal cannula (HFNC) therapy compared with conventional oxygen therapy (COT) or noninvasive ventilation (NIV) for the treatment of acute respiratory failure (ARF) in emergency departments (EDs).

Method

We comprehensively searched 3 databases (PubMed, EMBASE, and the Cochrane Library) for articles published from database inception to 12 July 2019. This study included only randomized controlled trials (RCTs) that were conducted in EDs and compared HFNC therapy with COT or NIV. The primary outcome was the intubation rate. The secondary outcomes were the mortality rate, intensive care unit (ICU) admission rate, ED discharge rate, need for escalation, length of ED stay, length of hospital stay, and patient dyspnea and comfort scores.

Result

Five RCTs (n = 775) were included. There was a decreasing trend regarding the application of HFNC therapy and the intubation rate, but the difference was not statistically significant (RR, 0.53; 95% CI, 0.26–1.09; p=0.08; I² = 0%). We found that compared with patients who underwent COT, those who underwent HFNC therapy had a reduced need for escalation (RR, 0.41; 95% CI, 0.22–0.78; p=0.006; I² = 0%), reduced dyspnea scores (MD −0.82, 95% CI −1.45 to −0.18), and improved comfort (SMD −0.76 SD, 95% CI −1.01 to −0.51). Compared with the COT group, the HFNC therapy group had a similar mortality rate (RR, 1.25; 95% CI, 0.79–1.99; p=0.34; I² = 0%), ICU admission rate (RR, 1.11; 95% CI, 0.58–2.12; p=0.76; I² = 0%), ED discharge rate (RR, 1.04; 95% CI, 0.63–1.72; p=0.87; I² = 0%), length of ED stay (MD 1.66, 95% CI −0.95 to 4.27), and hospital stay (MD 0.9, 95% CI −2.06 to 3.87).

Conclusion

Administering HFNC therapy in ARF patients in EDs might decrease the intubation rate compared with COT. In addition, it can decrease the need for escalation, decrease the patient's dyspnea level, and increase the patient's comfort level compared with COT.

High-flow nasal cannulae for respiratory support in adult intensive care patients

BACKGROUND

High-flow nasal cannulae (HFNC) deliver high flows of blended humidified air and oxygen via wide-bore nasal cannulae and may be useful in providing respiratory support for adult patients experiencing acute respiratory failure in the intensive care unit (ICU).

OBJECTIVES

We evaluated studies that included participants 16 years of age and older who were admitted to the ICU and required treatment with HFNC. We assessed the safety and efficacy of HFNC compared with comparator interventions in terms of treatment failure, mortality, adverse events, duration of respiratory support, hospital and ICU length of stay, respiratory effects, patient-reported outcomes, and costs of treatment.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 3), MEDLINE, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), Embase, Web of Science, proceedings from four conferences, and clinical trials registries; and we handsearched reference lists of relevant studies. We conducted searches from January 2000 to March 2016 and reran the searches in December 2016. We added four new studies of potential interest to a list of 'Studies awaiting classification' and will incorporate them into formal review findings during the review update.

SELECTION CRITERIA

We included randomized controlled studies with a parallel or cross-over design comparing HFNC use in adult ICU patients versus other forms of non-invasive respiratory support (low-flow oxygen via nasal cannulae or mask, continuous positive airway pressure (CPAP), and bilevel positive airway pressure (BiPAP)).

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed studies for inclusion, extracted data, and assessed risk of bias.

MAIN RESULTS

We included 11 studies with 1972 participants. Participants in six studies had respiratory failure, and in five studies required oxygen therapy after extubation. Ten studies compared HFNC versus low-flow oxygen devices; one of these also compared HFNC versus CPAP, and another compared HFNC versus BiPAP alone. Most studies reported randomization and allocation concealment inadequately and provided inconsistent details of outcome assessor blinding. We did not combine data for CPAP and BiPAP comparisons with data for low-flow oxygen devices; study data were insufficient for separate analysis of CPAP and BiPAP for most outcomes. For the primary outcomes of treatment failure (1066 participants; six studies) and mortality (755 participants; three studies), investigators found no differences between HFNC and low-flow oxygen therapies (risk ratio (RR), Mantel-Haenszel (MH), random-effects 0.79, 95% confidence interval (CI) 0.49 to 1.27; and RR, MH, random-effects 0.63, 95% CI 0.38 to 1.06, respectively). We used the GRADE approach to downgrade the certainty of this evidence to low because of study risks of bias and different participant indications. Reported adverse events included nosocomial pneumonia, oxygen desaturation, visits to general practitioner for respiratory complications, pneumothorax, acute pseudo-obstruction, cardiac dysrhythmia, septic shock, and cardiorespiratory arrest. However, single studies reported adverse events, and we could not combine these findings; one study reported fewer episodes of oxygen desaturation with HFNC but no differences in all other reported adverse events. We downgraded the certainty of evidence for adverse events to low because of limited data. Researchers noted no differences in ICU length of stay (mean difference (MD), inverse variance (IV), random-effects 0.15, 95% CI -0.03 to 0.34; four studies; 770 participants), and we downgraded quality to low because of study risks of bias and different participant indications. We found no differences in oxygenation variables: partial pressure of arterial oxygen (PaO₂)/fraction of inspired oxygen (FiO₂) (MD, IV, random-effects 7.31, 95% CI -23.69 to 41.31; four studies; 510 participants); PaO₂ (MD, IV, random-effects 2.79, 95% CI -5.47 to 11.05; three studies; 355 participants); and oxygen saturation (SpO₂) up to 24 hours (MD, IV, random-effects 0.72, 95% CI -0.73 to 2.17; four studies; 512 participants). Data from two studies showed that oxygen saturation measured after 24 hours was improved among those treated with HFNC (MD, IV, random-effects 1.28, 95% CI 0.02 to 2.55; 445 participants), but this difference was small and was not clinically significant. Along with concern about risks of bias and differences in participant indications, review authors noted a high level of unexplained statistical heterogeneity in oxygenation effect estimates, and we downgraded the quality of evidence to very low. Meta-analysis of three comparable studies showed no differences in carbon dioxide clearance among those treated with HFNC (MD, IV, random-effects -0.75, 95% CI -2.04 to 0.55; three studies; 590 participants). Two studies reported no differences in atelectasis; we did not combine these findings. Data from six studies (867 participants) comparing HFNC versus low-flow oxygen showed no differences in respiratory rates up to 24 hours according to type of oxygen delivery device (MD, IV, random-effects -1.51, 95% CI -3.36 to 0.35), and no difference after 24 hours (MD, IV, random-effects -2.71, 95% CI -7.12 to 1.70; two studies; 445 participants). Improvement in respiratory rates when HFNC was compared with CPAP or BiPAP was not clinically important (MD, IV, random-effects -0.89, 95% CI -1.74 to -0.05; two studies; 834 participants). Results showed no differences in patient-reported measures of comfort according to oxygen delivery devices in the short term (MD, IV, random-effects 0.14, 95% CI -0.65 to 0.93; three studies; 462 participants) and in the long term (MD, IV, random-effects -0.36, 95% CI -3.70 to 2.98; two studies; 445 participants); we downgraded the certainty of this evidence to low. Six studies measured dyspnoea on incomparable scales, yielding inconsistent study data. No study in this review provided data on positive end-expiratory pressure measured at the pharyngeal level, work of breathing, or cost comparisons of treatment.

AUTHORS' CONCLUSIONS

We were unable to demonstrate whether HFNC was a more effective or safe oxygen delivery device compared with other oxygenation devices in adult ICU patients. Meta-analysis could be performed for few studies for each outcome, and data for comparisons with CPAP or BiPAP were very limited. In addition, we identified some risks of bias among included studies, differences in patient groups, and high levels of statistical heterogeneity for some outcomes, leading to uncertainty regarding the results of our analysis. Consequently, evidence is insufficient to show whether HFNC provides safe and efficacious respiratory support for adult ICU patients.