Effects of high-flow nasal cannula oxygen therapy in bronchiectasis and hypercapnia: a retrospective observational study.

BACKGROUND: The effectiveness of high-flow nasal cannula (HFNC) therapy in patients with bronchiectasis experiencing hypercapnia remains unclear. Our aim was to retrospectively analyze the short-term outcomes of HFNC therapy in such patients, and to further explore the predictors of HFNC treatment failure in this particular patient population. METHODS: A retrospective review was conducted on patients with bronchiectasis who received HFNC (n = 70) for hypercapnia (arterial partial pressure of carbon dioxide, PaCO2 ≥ 45 mmHg) between September 2019 and September 2023. RESULTS: In the study population, 30% of patients presented with acidemia (arterial pH < 7.35) at baseline. Within 24 h of HFNC treatment, there was a significant reduction in PaCO2 levels by a mean of 4.0 ± 12.7 mmHg (95% CI -7.0 to -1.0 mmHg). Concurrently, arterial pH showed a statistically significant increase with a mean change of 0.03 ± 0.06 (95% CI 0.01 to 0.04). The overall hospital mortality rate in our study was 17.5%. The median length of hospital stay was 11.0 days (interquartile range [IQR] 8.0 to 16.0 days). Sub-analysis revealed no statistically significant differences in hospital mortality (19.0% vs. 20.4%, p = 0.896), length of hospital stay (median 14.0 days [IQR 9.0 to 18.0 days] vs. 10.0 days [IQR 7.0 to 16.0 days], p = 0.117) and duration of HFNC application (median 5.0 days [IQR 2.0 to 8.5 days] vs. 6.0 days [IQR 4.9 to 9.5 days], p = 0.076) between the acidemia group and the non-acidemia group (arterial pH ≥ 7.35). However, more patients in the non-acidemia group had do-not-intubate orders. The overall treatment failure rate for HFNC was 28.6%. Logistic regression analysis identified the APACHE II score (OR 1.24 per point) as the independent predictor of HFNC failure. CONCLUSIONS: In patients with bronchiectasis and hypercapnia, HFNC as an initial respiratory support can effectively reduce PaCO2 level within 24 h of treatment. A high APACHE II score has emerged as a prognostic indicator for HFNC treatment failure. These observations highlight randomized controlled trials to meticulously evaluate the efficacy of HFNC in this specific population.

High-flow nasal cannula therapy versus conventional oxygen therapy for adult patients after cardiac surgery: A systemic review and meta-analysis.

BACKGROUND: Oxygen therapy constitutes a crucial element of post-cardiac operative care. The study assessed the effectiveness of high-flow nasal cannula (HFNC) in comparison to conventional oxygen therapy (COT). OBJECTIVES: The aim of the study was to assess the effectiveness of HFNC in comparison to COT for adult patients following cardiac surgery. METHODS: We conducted a comprehensive search of Embase, PubMed, Scopus, Cochrane Library, and Web of Science databases from inception until April 18, 2023, to identify randomized controlled trials (RCTs) and crossover studies that compared the efficacy of HFNC with COT in adult patients following cardiac surgery. RESULTS: The meta-analysis included nine studies, consisting of eight RCTs and one crossover study. Compared with COT, HFNC could reduce the need for escalation of respiratory support (RR 0.67, 95% CI: 0.48 to 0.93, P = 0.02), decrease arterial partial pressure of carbon dioxide (PaCO2) levels (MD -3.14, 95% CI: -4.90 to -1.39, P<0.001), and increase forced expiratory volume in 1 second (FEV1) levels (MD 0.08, 95% CI: 0.02 to 0.15, P = 0.02). There was no significant difference between the HFNC and COT groups in terms of mortality, intubation rate, respiratory rate, heart rate, intensive care unit and hospital length of stay, arterial partial pressure of oxygen (PaO2), forced vital capacity, and complications of atrial fibrillation and delirium. CONCLUSION: Compared with COT, HFNC could decrease the need for escalation of respiratory support, lower PaCO2 levels, and elevate FEV1 levels in patients following cardiac surgery.

Optimal flow of high-flow nasal cannula oxygenation to prevent desaturation during sedation for bronchoscopy: a randomized controlled study.

BACKGROUND: Although high-flow nasal cannula (HFNC) oxygenation is currently recommended to prevent desaturation during sedation for bronchoscopy, there is no consensus on an optimal flow rate. OBJECTIVE: To determine the optimal oxygen flow rate for HFNC to effectively prevent desaturation during sedation for bronchoscopy. DESIGN: Prospective, randomized, and controlled study. METHODS: Patients (n = 240) scheduled for bronchoscopy were randomized to receive HFNC with propofol sedation (fraction of inspired oxygen, 100%) at one of six flow rates of 10, 20, 30, 40, 50, and 60 L/min, designated as groups 1-6, respectively. RESULTS: The incidence of desaturation significantly decreased by increasing the oxygen flow rate (42.5%, 17.5%, 15%, 10%, 2.5%, and 0% for groups 1-6, respectively, p < 0.0001). The optimal oxygen flow rate for HFNC determined by probit regression to effectively prevent desaturation in 95% of patients was 43.20 (95% confidence interval, 36.43-55.96) L/min. The requirement for airway intervention was significantly decreased by increasing the oxygen flow rate. CONCLUSION: An HFNC flow rate of 50-60 L/min is recommended to prevent desaturation during sedation for bronchoscopy. REGISTRATION: NCT05298319 at ClinicalTrials.gov.

High-flow nasal cannula oxygenation during bronchoscopyMany patients undergo a special test to check their airways for problems. Sometimes, doctors need to take out a small part of the area that's causing trouble to find out what's wrong. But during this test, some patients can struggle to get enough oxygen, which can even be life-threatening. To help with this, there's a device called a high-flow nasal cannula (HFNC). It gives patients adjustable amounts of oxygen, like a gentle breeze into their nose. But doctors weren't sure how much oxygen was best during this test. So, we studied 240 patients using HFNC at different oxygen levels­like slow, medium, and fast flows. We found that the higher the oxygen flow, the less likely patients were to have oxygen problems. For example, at the lowest flow (10 liters per minute), about 42.5% of patients had oxygen trouble, but at the highest flow (60 liters per minute), none did. And we figured out that a flow rate around 43.2 liters per minute would prevent 95% patients from having oxygen problems. So, we recommend using a flow rate between 50 and 60 liters per minute during this test to keep patients safe from oxygen issues.

Airway stenting for liberation from positive pressure ventilation in patients with central airway obstruction presenting with acute respiratory failure.

BACKGROUND: Central airway obstruction (CAO) can lead to acute respiratory failure (RF) necessitating positive pressure ventilation (PPV). The efficacy of airway stenting to aid liberation from PPV in patients with severe acute RF has been scarcely published. We present a systematic review and our recent experience. METHODS: A systematic review of PubMed was performed, and a retrospective review of cases performed at our two institutions from 2018 to 2022 in adult patients who needed stent insertion for extrinsic or mixed CAO complicated by RF necessitating PPV. RESULTS: Fifteen studies were identified with a total of 156 patients. The weighted mean of successful liberation from PPV post-stenting was 84.5% and the median survival was 127.9 days. Our retrospective series included a total of 24 patients. The most common etiology was malignant CAO (83%). The types of PPV used included high-flow nasal cannula (HFNC) (21%), non-invasive ventilation (NIV) (17%) and Invasive Mechanical Ventilation (62%). The overall rate of successful liberation from PPV was 79%, with 55% of HFNC and NIV cases being liberated immediately post-procedure. The median survival of the patients with MCAO that were successfully liberated from PPV was 74 days (n = 16, range 3-893 days), and for those with that failed to be liberated from PPV, it was 22 days (n = 4, range 9-26 days). CONCLUSION: In patients presenting with acute RF from extrinsic or mixed morphology CAO requiring PPV, airway stenting can successfully liberate most from the PPV. This may allow patients to receive pathology-directed treatment and better end-of-life care.

Occurrence of hyperoxia during iNO treatment for persistent pulmonary hypertension of the newborn: a cohort study.

High concentrations of oxygen are often needed to optimize oxygenation in infants with persistent pulmonary hypertension (PPHN), but this can also increase the risk of hyperoxemia. We determined the occurrence of hyperoxemia in infants treated for PPHN. Medical records of infants ≥ 34 + 0 weeks gestational age (GA) who received inhaled nitric oxide (iNO) were retrospectively reviewed for oxygenation parameters during iNO therapy. Oxygen was manually titrated to target arterial oxygen tension (PaO2) 10-13 kPa and peripheral oxygen saturation (SpO2) 92-98%. The main study outcomes were the incidence and duration of hyperoxemia and hypoxemia and the fraction of inspired oxygen (FiO2). A total of 181 infants were included. The median FiO2 was 0.43 (IQR 0.34-0.56) and the maximum FiO2 was 1.0 in 156/181 (86%) infants, resulting in at least one PaO2 > 13 kPa in 149/181 (82%) infants, of which 46/149 (31%) infants had minimal one PaO2 > 30 kPa. SpO2 was > 98% in 179/181 (99%) infants for 17.7% (8.2-35.6%) of the iNO time. PaO2 < 10 kPa occurred in 160/181 (88%) infants, of which 81/160 (51%) infants had minimal one PaO2 < 6.7 kPa. SpO2 was < 92% in 169/181 (93%) infants for 1.6% (0.5-4.3%) of the iNO time.    Conclusion: While treatment of PPHN is focused on preventing and reversing hypoxemia, hyperoxemia occurs inadvertently in most patients. What is Known: • High concentrations of oxygen are often needed to prevent hypoxemia-induced deterioration of PPHN, but this can also increase the risk of hyperoxemia. • Infants with persistent pulmonary hypertension may be particularly vulnerable to the toxic effects of oxygen, and hyperoxemia could further induce pulmonary vasoconstriction, potentially worsening the condition. What is New: • Hyperoxemia occurs in the majority of infants with PPHN during treatment with iNO. • Infants with PPHN spent a considerably longer period with saturations above the target range compared to saturations below the target range.

Perioperative hyperoxia- impact on myocardial biomarkers, strain and outcome in high-risk patients undergoing non-cardiac surgery: Protocol for a prospective randomized controlled trial.

BACKGROUND: Supplemental oxygen is used during every general anesthesia. However, for the maintenance phase of a general anesthesia, in most cases the longest part of anesthesia, only scarce evidence of dosing supplemental oxygen exists. Oxygen is a well-known coronary vasoconstrictor and thus may contribute to cardiovascular complications especially in vulnerable high-risk patients with coronary artery disease undergoing major non-cardiac surgery. Myocardial biomarkers are early indicators of myocardial injury. Oxygen supply demand mismatches due to coronary artery disease aggravated by hyperoxia might be displayed by changes from the biomarker's baseline-values. This study is designed to detect changes in myocardial biomarkers levels associated with perioperative hyperoxia. METHODS: This prospective randomized controlled interventional trial investigates the impact of maintaining perioperative high oxygen supplementation in high-risk patients undergoing non-cardiac vascular surgery on cardiac biomarkers, myocardial strain and outcome in 110 patients. Patients are allocated to be supplemented with either 0.3 (normal) or 0.8 (high) fraction of inspired oxygen (FiO2) perioperatively. Included is a short crossover phase during which transesophageal echocardiography is used to evaluate myocardial function at FiO2 0.3 and 0.8 by strain analysis in each patient. Patients will be followed up for complications at 30 days and 1 year. CONCLUSION: The trial is designed to evaluate perioperative changes from baseline myocardial biomarkers associated with perioperative FiO2. Furthermore, exploration and correlation of changes in biomarkers, acute early changes in myocardial function and clinical outcomes induced by different FiO2 may be possible.

Use of high-flow nasal cannula versus other noninvasive ventilation techniques or conventional oxygen therapy for respiratory support following pediatric cardiac surgery: A systematic review and meta-analysis.

INTRODUCTION: Noninvasive respiratory support may be provided to decrease the risk of postextubation failure following surgery. Despite these efforts, approximately 3%-27% of infants and children still experience respiratory failure after tracheal extubation following cardiac surgery. This systematic review evaluates studies comparing the efficacy of high-flow nasal cannula to conventional oxygen therapy such as nasal cannula and other noninvasive ventilation techniques in preventing postextubation failure in this patient population. METHODS: A systematic and comprehensive search was conducted in major databases including MEDLINE, EMBASE, Web of Science, and Central. The search encompassed articles focusing on the prophylactic use of high-flow nasal cannula following tracheal extubation in pediatric patients undergoing cardiac surgery for congenital heart disease. The inclusion criteria for this review consisted of randomized clinical trials as well as observational, cohort, and case-control studies. RESULTS: A total of 1295 studies were screened and 12 studies met the inclusion criteria. These 12 studies included a total of 1565 children, classified into three groups: seven studies compared high-flow nasal cannula to noninvasive ventilation techniques, four studies compared high-flow nasal cannula to conventional oxygen therapy, and one observational single-arm study explored the use of high-flow nasal cannula with no control group. There was no significant difference in the incidence of tracheal reintubation between high-flow nasal cannula and conventional oxygen therapy (risk ratio [RR] = 0.67, 95% confidence interval [CI]: 0.24-1.90, p = .46). However, there was a lower incidence of tracheal reintubation in patients who were extubated to high-flow nasal cannula versus those extubated to noninvasive ventilation techniques (RR = 0.45, 95% CI: 0.32-0.63, p < .01). The high-flow nasal cannula group also demonstrated a lower mortality rate compared to the noninvasive ventilation techniques group (RR = 0.31, 95% CI: 0.16-0.61, p < .01) as well as a shorter postoperative length of stay (mean difference = -8.76 days, 95% CI: -13.08 to -4.45, p < .01) and shorter intensive care length of stay (mean difference = -4.63 days, 95% CI: -9.16 to -0.11, p = .04). CONCLUSION: High-flow nasal cannula is more effective in reducing the rate of postextubation failure compared to other forms of noninvasive ventilation techniques following surgery for congenital heart disease in pediatric-aged patients. high-flow nasal cannula is also associated with lower mortality rates and shorter length of stay. However, when comparing high-flow nasal cannula to conventional oxygen therapy, the findings were inconclusive primarily due to a limited number of scientific studies available on this specific comparison. Future study is needed to further define the benefit of high-flow nasal cannula compared to conventional oxygen therapy and various types of noninvasive ventilation techniques.

Retrospective study of serial polysomnograms of bronchopulmonary dysplasia patients with oxygen dependence.

INTRODUCTION: This retrospective study describes characteristics of serial polysomnograms (PSGs) of BPD patients on home oxygen therapy and describes PSG parameters associated with discontinuation of supplemental oxygen. METHODS: A single-center study was performed at Children's Hospital Los Angeles, where serial PSGs for 44 patients with BPD infants discharged on home oxygen therapy were extracted for maximum of five PSGs or until oxygen discontinuation. Clinical and polysomnography data was collected. Characteristics of PSG1 were compared amongst the patients who were weaned from oxygen after PSG2 and PSG3. RESULTS: Of 44 patients, 68.2% of patients were males with median birth gestational age of 26 weeks (IQR: 24.6-28.1), median birthweight of 777.5 g (IQR: 632.5-1054 g) and 77.3% of the cohort had severe BPD. A total of 138 PSGs were studied between all 44 patients serially. When comparing PSG1 and PSG2 parameters, statistically significant improvement was noted in multiple parameters. Median baseline SpO2, peak RR, and average PETCO2 were found to be potential predictors of prolonged oxygen use. Gestational age and birth weight were not associated with prolonged oxygen use after PSG3. The median age of oxygen discontinuation was calculated to be about 2 years of age. CONCLUSIONS: The severity of hypoxia and tachypnea on initial infant PSG are associated with prolonged oxygen therapy past 2 years of age. Growth and development of lungs with maturation of control of breathing help improve these parameters over time regardless of BPD severity. The study may inform discussions between providers and parents for patients discharged home on oxygen therapy.

Comparison of high-flow nasal cannula oxygenation and non-invasive ventilation for postoperative pediatric cardiac surgery: a meta-analysis.

OBJECTIVE: To evaluate the efficacy of high-flow nasal cannula oxygenation (HFNC) versus non-invasive ventilation (NIV) in pediatric patients post-congenital heart surgery (CHS) through a meta-analysis. METHODS: A comprehensive literature search was conducted across the Chinese biomedical literature database, Vip database, CNKI, Wanfang, PubMed, Embase, Cochrane Library, and Web of Science until December 20, 2022. We selected RCTs or cohort studies that met inclusion criteria for a meta-analysis using RevMan 5.4 software. RESULTS: Our search yielded five publications, comprised of one randomized controlled trial and four cohort studies. Meta-analysis revealed a significant reduction in reintubation rates in children post-CHS treated with HFNC as compared to NIV [RR = 0.36, 95%CI(0.25 ~ 0.53), P < 0.00001]. There was also a notable reduction in the duration of ICU stay [MD = -4.75, 95%CI (-9.38 ~ -0.12), P = 0.04]. No statistically significant differences were observed between HFNC and NIV in terms of duration of mechanical ventilation, 24 h PaO2, and PaCO2 post-treatment (P > 0.05). Furthermore, both groups showed no significant difference in the duration of extracorporeal circulation [MD = -8.27, 95%CI(-17.16 ~ 0.62), P = 0.07]. CONCLUSIONS: For pediatric patients post-CHS, HFNC appears to be more effective than NIV in reducing reintubation rates and shortening the CICU stay.

Excessive Oxygen Administration in High-Risk Patients Admitted to Medical and Surgical Wards Monitored by Wireless Pulse Oximeter.

The monitoring of oxygen therapy when patients are admitted to medical and surgical wards could be important because exposure to excessive oxygen administration (EOA) may have fatal consequences. We aimed to investigate the association between EOA, monitored by wireless pulse oximeter, and nonfatal serious adverse events (SAEs) and mortality within 30 days. We included patients in the Capital Region of Copenhagen between 2017 and 2018. Patients were hospitalized due to acute exacerbation of chronic obstructive pulmonary disease (AECOPD) or after major elective abdominal cancer surgery, and all were treated with oxygen supply. Patients were divided into groups by their exposure to EOA: no exposure, exposure for 1-59 min or exposure over 60 min. The primary outcome was SAEs or mortality within 30 days. We retrieved data from 567 patients for a total of 43,833 h, of whom, 63% were not exposed to EOA, 26% had EOA for 1-59 min and 11% had EOA for ≥60 min. Nonfatal SAEs or mortality within 30 days developed in 24%, 12% and 22%, respectively, and the adjusted odds ratio for this was 0.98 (95% CI, 0.96-1.01) for every 10 min. increase in EOA, without any subgroup effects. In conclusion, we did not observe higher frequencies of nonfatal SAEs or mortality within 30 days in patients exposed to excessive oxygen administration.

Reversal of arterial oxygen desaturation with the use of an oxygen concentrator during injectable anaesthesia in feral cats positioned in the Trendelenburg, dorsal or lateral surgical position.

INTRODUCTION: This study observed the effects of oxygen supplementation, via an oxygen concentrator, on peripheral arterial blood oxygenation (SpO2) measured by pulse oximetry in anaesthetised cats undergoing spay in three different surgical positions. A total of 192 female feral cats were investigated for a large-scale trap-neuter-release program. Cats were anaesthetised with an intramuscular combination of butorphanol (0,4 mg / kg), ketamine (7-10 mg / kg) and medetomidine (0,03-0,05 mg / kg). Cats were randomly allocated to undergo spay in either Trendelenburg (TR) (70° downward head tilt), lateral (LR) or dorsal (DR) recumbency. Cats were breathing spontaneously either room air or 2 L/minute oxygen via a tight-fitting face mask. Pulse rate (in beats per minute), respiratory rate (in breaths per minute) and SpO2 (in percentage) were measured at baseline in left lateral recumbency and afterwards continuously after being positioned in allocated surgical position. At the end of surgery, cats were placed again in left recumbency, and all parameters were re-evaluated after five minutes. Overall, 33 % of cats showed severe arterial oxygen desaturation (SpO2 < 90 %) at baseline when breathing room air. When oxygen was supplemented during the procedure, arterial oxygen desaturation resolved in all cats. At the end of the procedure, 29 % of cats were hypoxaemic when oxygen was not supplemented, with an overall higher percentage of hypoxaemic cats in TR as compared to DR and LR recumbencies. All cats recovered well from surgery and were released within 24 hours post-anaesthesia. Arterial oxygen desaturation is frequent in cats anaesthetised with injectable anaesthesia for spay under field conditions. Oxygen supplementation administered via a tight-fitting mask resolved arterial oxygen desaturation in this feral cat population regardless of the surgical position and therefore oxygen supplementation is recommended in any case.

INTRODUCTION: Cette étude a observé les effets d'une supplémentation en oxygène, via un concentrateur d'oxygène, sur l'oxygénation du sang artériel périphérique (SpO2) mesurée par oxymétrie de pouls chez des chats anesthésiés subissant une stérilisation dans trois positions chirurgicales différentes. Au total, 192 chats sauvages femelles ont été examinés dans le cadre d'un programme de piégeage, de stérilisation et de remise en liberté à grande échelle. Les chats ont été anesthésiés avec une combinaison de butorphanol (0,4 mg / kg), de kétamine (7­10 mg / kg) et de médétomidine (0,03­0,05 mg / kg) appliquée par voie intramusculaire. Les chats ont été répartis au hasard pour subir une stérilisation en position de Trendelenburg (TR) (inclinaison de la tête de 70° vers le bas), en décubitus latéral (LR) ou en décubitus dorsal (DR). Les chats respiraient spontanément soit de l'air ambiant, soit de l'oxygène à raison de 2 L/minute par l'intermédiaire d'un masque facial bien ajusté. Le pouls (en battements par minute), la fréquence respiratoire (en respirations par minute) et la SpO2 (en pourcentage) ont été mesurés au départ en décubitus latéral gauche, puis en continu après avoir été placés dans la position chirurgicale attribuée. À la fin de l'opération, les chats ont été replacés en décubitus latéral gauche et tous les paramètres ont été réévalués au bout de cinq minutes. Dans l'ensemble, 33 % des chats présentaient une désaturation sévère en oxygène artériel (SpO2 < 90 %) au départ lorsqu'ils respiraient de l'air ambiant. Lorsque de l'oxygène a été ajouté pendant la procédure, la désaturation en oxygène artériel s'est résorbée chez tous les chats. À la fin de l'intervention, 29 % des chats étaient hypoxémiques lorsque l'oxygène n'était pas administré, avec un pourcentage global plus élevé de chats hypoxémiques en décubitus dorsal qu'en décubitus latéral. Tous les chats se sont bien remis de l'opération et ont été libérés dans les 24 heures suivant l'anesthésie. La désaturation en oxygène artériel est fréquente chez les chats anesthésiés par injection pour la stérilisation dans des conditions de terrain. La supplémentation en oxygène administrée via un masque étanche a résolu la désaturation en oxygène artériel dans cette population de chats sauvages, quelle que soit la position chirurgicale et la supplémentation en oxygène est donc recommandée dans tous les cas.

Intraoperative high flow oxygen therapy for tubeless anaesthesia in thoracoscopic surgery.

Tubeless anaesthesia has become widespread in videothoracoscopic surgery, even in major procedures such as lobectomies. There are several advantages in avoiding general anaesthesia and one-lung mechanical ventilation, such as faster recovery and shorter hospital stays. However, hypoxaemia and hypercapnia are the most reported causes of conversion to general anaesthesia. High Flow Oxygen Therapy (HFOT) generates flow-dependent positive end-expiratory pressure, improves oxygenation and also carbon dioxide washout by flow-dependent dead space flushing. For this reason, intraoperative HFOT may reduce the rate of conversion to general anaesthesia. We report our experience with intraoperative HFOT in a 71-year-old female with lung adenocarcinoma undergoing VATS upper left lobectomy.

Smoking and home oxygen therapy: a review and consensus statement from a multidisciplinary Swedish taskforce.

BACKGROUND: Home oxygen therapy (HOT) improves survival in patients with hypoxaemic chronic respiratory disease. Most patients evaluated for HOT are former or active smokers. Oxygen accelerates combustion and smoking may increase the risk of burn injuries and fire hazards; therefore, it is considered a contraindication for HOT in many countries. However, there is variability in the practices and policies regarding this matter. This multidisciplinary Swedish taskforce aimed to review the potential benefits and risks of smoking in relation to HOT, including medical, practical, legal and ethical considerations. METHODS: The taskforce of the Swedish Respiratory Society comprises 15 members across respiratory medicine, nursing, medical law and ethics. HOT effectiveness and adverse risks related to smoking, as well as practical, legal and ethical considerations, were reviewed, resulting in five general questions and four PICO (population-intervention-comparator-outcome) questions. The strength of each recommendation was rated according to the GRADE (grading of recommendation assessment, development and evaluation) methodology. RESULTS: General questions about the practical, legal and ethical aspects of HOT were discussed and summarised in the document. The PICO questions resulted in recommendations about assessment, management and follow-up of smoking when considering HOT, if HOT should be offered to people that meet the eligibility criteria but who continue to smoke, if a specific length of time of smoking cessation should be considered before assessing eligibility for HOT, and identification of areas for further research. CONCLUSIONS: Multiple factors need to be considered in the benefit/risk evaluation of HOT in active smokers. A systematic approach is suggested to guide healthcare professionals in evaluating HOT in relation to smoking.

A Phase II Study of High-Flow Nasal Cannula for Relieving Dyspnea in Advanced Cancer Patients.

CONTEXT: The efficacy and tolerability of high-flow nasal cannula (HFNC) for relieving dyspnea in advanced cancer patients with limited prognosis requires elucidation. OBJECTIVES: The primary aim of this trial was to assess the efficacy and tolerability of HFNC regarding dyspnea including severe as well as moderate for longer durations in patients under palliative care. METHODS: In this prospective study, hospitalized patients with advanced cancer who had dyspnea at rest (numeric rating scale, NRS≥3) and hypoxemia were enrolled. They were treated with HFNC for five days in the respiratory unit. Primary endpoint was mean change of modified Borg scale at 24 hours. Key secondary endpoints consisted of mean changes in modified Borg scale during the study period and feasibility (Trial Identifier, UMIN000035738). RESULTS: Between February 2019 and February 2022, 25 patients were enrolled and 21 were analyzed. Twenty patients used inspired oxygen and the mean fraction of inspired oxygen (FiO2) was 0.34 (range, 0.21-1.0). At baseline, mean NRS (dyspnea) was 5.9 (range, 3-10). Median survival time was 19 days (range, 3-657). The mean change of modified Borg scale was 1.4 (80% confidence interval [CI]: 0.8-1.9) at 24 hours, 12 patients (57%) showed 1.0 points improvement of modified Borg scale. Within two hours, 15 patients showed 1.0 points improvement of modified Borg scale and such early responders were likely to maintain dyspnea improvement for 24 hours. Nineteen patients could continue HFNC for 24 hours and 11 patients completed five days of HFNC. CONCLUSION: To our knowledge, this trial is the first prospective study to assess the five-day efficacy and tolerability of HFNC for dyspnea in patients under palliative care. Although this did not reach the prespecified endpoint, about half of the patients showed 1.0 point improvement, a minimally clinically important difference (MCID) in the chronic lung disease. HFNC can be a palliative treatment option in advanced cancer patients with dyspnea.

Outcomes of liver transplantation for hepatopulmonary syndrome in patients with concomitant respiratory disease.

BACKGROUND & AIMS: Concomitant respiratory disease is a common finding in patients with hepatopulmonary syndrome (HPS). Among patients who underwent liver transplantation (LT) for HPS, we compared characteristics and outcome of patients with versus without concomitant respiratory disease. METHODS: This single center retrospective observational study included patients with HPS who underwent LT between 1999 and 2020. RESULTS: During the study period, 32 patients with HPS received a LT; nine (28%) with concomitant respiratory disease of whom one required a combined lung-liver transplantation. Patients with concomitant respiratory disease had higher PaCO2 (38 vs. 33 mm Hg, p = .031). The 30-day postoperative mortality was comparable, but the estimated cumulative probability of resolution of oxygen therapy after LT in HPS patients with versus those without concomitant respiratory disease was lower: 63% versus 91% at 12 months and 63% versus 100% at 18 months (HR 95% CI .140-.995, p = .040). In addition to the presence of concomitant respiratory disease (p = .040), history of smoking (p = .012), and high baseline 99mTcMAA shunt fraction (≥20%) (p = .050) were significantly associated with persistent need of oxygen therapy. The 5-year estimated cumulative probability of mortality in patients with concomitant respiratory disease was worse: 50% versus 23% (HR 95% CI .416-6.867, p = .463). CONCLUSIONS: The presence of a concomitant respiratory disease did not increase the short-term postoperative mortality after LT in patients with HPS. However, it resulted in a longer need for oxygen therapy.

Noninvasive respiratory support preventing reintubation after pediatric cardiac surgery-A systematic review.

OBJECTIVE: To analyze the optimal postextubation respiratory support in pediatric cardiac surgery patients. DESIGN: Systematic review of randomized controlled trials. SETTING: Pediatric or neonatal intensive care units. PARTICIPANTS: All aged children (<16 years) having cardiac surgery and postoperative invasive ventilation. INTERVENTION: Noninvasive respiratory support, including high flow nasal cannula (HFNC), conventional oxygen therapy (COT), noninvasive positive pressure ventilation (NIPPV), continuous positive pressure (CPAP), and noninvasive high-frequency oscillatory ventilation (NHFOV). MEASUREMENT AND MAIN RESULTS: Studies were not pooled for statistical synthesis due to the limited number and quality of the included studies. Risk ratios with 95% confidence intervals were calculated for individual studies. A total of 167 studies were screened and six were included. The risk of bias was low in one, high in one, and had some concerns in four of the studies. Extubation failure (defined as reintubation) was the main outcome of interest. Risk ratio for reintubation was 0.10 (CI 0.02-0.40) and 1.07 (CI 0.16-7.26) in HFNC versus COT, 0.49 (CI 0.05-5.28) in HFNC versus NIPPV, 0.40 (CI 0.08-1.94) in HFNOV versus CPAP, 0.75 (CI 0.26-2.18) in HFNOV versus NIPPV, and 1.37 (CI 0.33-5.73) in CPAP versus NIPPV. Treatment durations did not differ between the groups. CONCLUSION: We did not find clear evidence of a difference in reintubation rates and other clinical outcomes between different noninvasive ventilation strategies. Evidence certainty was assessed to be very low due to the risk of bias, the small number of included studies, and high imprecision. Future quality studies are needed to determine the optimal postextubation support in pediatric cardiac surgery patients.

Transnasal Humidified Rapid Insufflation Ventilatory Exchange in Endoscopic Esophageal Surgery.

OBJECTIVES: Transnasal humidified rapid insufflation ventilatory exchange (THRIVE) describes apneic oxygenation using humidified high flow nasal-cannula oxygen. Although it has been described as a sole mode of oxygenation in endoscopic laryngotracheal surgery, its use in endoscopic esophageal surgery under general anesthesia with neuromuscular paralysis has not previously been described. The objective of this study is to assess the safety and efficacy of THRIVE in esophagology. METHODS: We conducted a retrospective review of adult patients undergoing esophageal procedures under general anesthesia who were oxygenated using THRIVE at two academic institutions. Demographic, clinical, and anesthesiologic data were collected and analyzed. RESULTS: 14 cases performed from March 2021 to March 2022 met inclusion criteria. 13/14 (92.9%) of patients were able to maintain oxygenation throughout the entirety of their procedure. The mean apneic time was 17.9 minutes with a maximum of 32 minutes. One patient required "rescue" intubation due to failure to maintain oxygenation. Excluding the sole THRIVE failure, the median SpO2 at the conclusion of surgery was 99% (range 94-100%). A linear regression model yielded an increase in EtCO2 of 0.95 mmHg/min or 0.127 kPa/min. SpO2 was negatively associated with both tobacco pack-year smoking history (R2 = 0.343, P = .014) and BMI (R2 = 0.238, P = .038). CONCLUSION: THRIVE is a feasible, safe, and efficacious means of apneic oxygenation for patients undergoing esophageal endoscopic surgery under general anesthesia with neuromuscular paralysis, which may be particularly beneficial in patients with airway stenosis, as post-intubation changes can have severe clinical implications for this patient population. Obese patients and tobacco smokers may be at increased risk of oxygen desaturation when using THRIVE.