BTS guideline for oxygen use in adults in healthcare and emergency settings

Effects of Oxygenation Targets on Mortality in Critically Ill Patients in Intensive Care Units: A Systematic Review and Meta-Analysis

BACKGROUND

The effects of oxygenation targets (partial pressure of arterial oxygen [Pa o2 ], arterial oxygen saturation [Sa o2 ]/peripheral oxygen saturation [Sp o2 ], or inspiratory oxygen concentration [Fi o2 ] on clinical outcomes in critically ill patients remains controversial. We reviewed the existing literature to assess the effects of lower and higher oxygenation targets on the mortality rates of critically ill intensive care unit (ICU) patients.

METHODS

MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Web of Science databases were searched from their dates of inception to December 31, 2022, for randomized controlled trials (RCTs) comparing lower and higher oxygenation targets for critically ill patients ≥18 years of age undergoing mechanical ventilation, nasal cannula, oxygen mask, or high-flow oxygen therapy in the ICU. Data extraction was conducted independently, and RoB 2.0 software was used to evaluate the quality of each RCT. A random-effects model was used for the meta-analysis to calculate the relative risk (RR). We used the I 2 statistic as a measure of statistical heterogeneity. Certainty of evidence was assessed according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) guidelines.

RESULTS

We included 12 studies with a total of 7416 patients participating in RCTs. Oxygenation targets were extremely heterogeneous between studies. The meta-analysis found no differences in mortality between lower and higher oxygenation targets for critically ill ICU patients (relative risk [RR], 1.00; 95% confidence interval [CI], 0.93-1.09; moderate certainty). The incidence of serious adverse events (RR, 0.93; 95% CI, 0.85-1.00; high certainty), mechanical ventilation-free days through day 28 (mean difference [MD], -0.05; 95%CI, -1.23 to 1.13; low certainty), the number of patients requiring renal replacement therapy (RRT) (RR, 0.96; 95% CI, 0.84-1.10; low certainty), and ICU length of stay (MD, 1.05; 95% CI, -0.04 to 2.13; very low certainty) also did not differ among patients with lower or higher oxygenation targets.

CONCLUSIONS

Critically ill ICU patients ≥18 years of age managed with lower and higher oxygenation targets did not differ in terms of mortality, RRT need, mechanical ventilation-free days through day 28, or ICU length of stay. However, due to considerable heterogeneity between specific targets in individual studies, no conclusion can be drawn regarding the effect of oxygenation targets on ICU outcomes.

Oxygen therapy in acute hypoxemic respiratory failure: guidelines from the SRLF-SFMU consensus conference

INTRODUCTION

Although largely used, the place of oxygen therapy and its devices in patients with acute hypoxemic respiratory failure (ARF) deserves to be clarified. The French Intensive Care Society (Société de Réanimation de Langue Française, SRLF) and the French Emergency Medicine Society (Société Française de Médecine d'Urgence, SFMU) organized a consensus conference on oxygen therapy in ARF (excluding acute cardiogenic pulmonary oedema and hypercapnic exacerbation of chronic obstructive diseases) in December 2023.

METHODS

A committee without any conflict of interest (CoI) with the subject defined 7 generic questions and drew up a list of sub questions according to the population, intervention, comparison and outcomes (PICO) model. An independent work group reviewed the literature using predefined keywords. The quality of the data was assessed using the GRADE methodology. Fifteen experts in the field from both societies proposed their own answers in a public session and answered questions from the jury (a panel of 16 critical-care and emergency medicine physicians, nurses and physiotherapists without any CoI) and the public. The jury then met alone for 48 h to write its recommendations.

RESULTS

The jury provided 22 statements answering 11 questions: in patients with ARF (1) What are the criteria for initiating oxygen therapy? (2) What are the targets of oxygen saturation? (3) What is the role of blood gas analysis? (4) When should an arterial catheter be inserted? (5) Should standard oxygen therapy, high-flow nasal cannula oxygen therapy (HFNC) or continuous positive airway pressure (CPAP) be preferred? (6) What are the indications for non-invasive ventilation (NIV)? (7) What are the indications for invasive mechanical ventilation? (8) Should awake prone position be used? (9) What is the role of physiotherapy? (10) Which criteria necessarily lead to ICU admission? (11) Which oxygenation device should be preferred for patients for whom a do-not-intubate decision has been made?

CONCLUSION

These recommendations should optimize the use of oxygen during ARF.

Cyclosporin A as an Add-On Therapy to a Corticosteroid-Based Background Treatment in Patients with COVID-19: A Multicenter, Randomized Clinical Trial

Background: In susceptible hosts, SARS-CoV2-induced hyperinflammation accounts for an increased mortality. The search of adjuvant immunomodulatory therapies has been ongoing ever since the pandemic outbreak. Aim: Our purpose was to evaluate the efficacy of cyclosporin A (CsA) as an add-on therapy to the standard of care (SoC) in patients with severe COVID-19 pneumonia. Methods: We conducted a randomized clinical trial in patients admitted to eight Spanish tertiary hospitals. Patients were stratified into two severity categories and randomized in a 1:1 ratio to receive a corticosteroid-based standard therapy with or without CsA. The primary endpoint was FiO2 recovery by Day 12 without relapses. Results: 109 patients were included and randomized, and 98 of them considered for the mITT population (51 assigned to the CsA + SoC group and 47 to the SoC group). A total of 35 (68.6%) patients from the CsA + SoC group and 32 (71.1%) patients from the SoC group reached the primary endpoint in the mITT analysis. No differences were found after stratification into age groups, in the severity level at admission, or in a combination of both. Overall, the time to FiO2 normalization was 7.4 days vs. 7.9 days in the experimental and control groups, respectively. Global mortality was 8.2%. Severe adverse events were uncommon and equally distributed between arms. Conclusion: The addition of CsA did not show differences over a corticosteroid-based treatment in the clinical course of the included patients. A better identification of candidates who will benefit from receiving immunomodulatory drugs is necessary in future studies.

Predictors of high-flow nasal cannula failure in COVID-19 patients in a northern Peruvian hospital

OBJECTIVES

To determine predictors of high-flow nasal cannula (HFNC) failure in COVID-19 patients in a hospital in northern Peru.

METHODOLOGY

A retrospective cohort study was conducted during the months of March and May 2021. Data collection was based on a follow-up of 156 hospitalized patients with a diagnosis of COVID-19 who were users of HFNC. Epidemiological factors and clinical outcomes of treatment were analyzed from medical records. Epidemiological, analytical, and HFNC use-related characteristics were described using measures of absolute and relative frequencies, measures of central tendency, and dispersion. A multivariate Poisson regression analysis with robust variance and a 95% confidence interval was performed.

RESULTS

We found that age, SpO2/FiO2, work of breathing (WOB scale) at admission, degree of involvement, type of infiltrate on CT scan, lymphocytes, c-reactive protein, and D-dimer were significantly associated with failure of HFNC (p < 0.05). In addition, the WOB scale, PaO2/FiO2, SaO2/FiO2, and ROX index were variables that presented statistical significance (p < 0.0001). In the multivariate analysis model, a risk of failure of HFNC was determined with age > = 60 years [RRa 1.39 (1.05-1.85)] and PaO2/FiO2 score less than 100 [Rra 1.65 (0.99-2.76)].

CONCLUSIONS

Predictors to failure of HFNC are age older than 60 years and minimally significantly lower PaO2/FiO2 than 100.

Efflux pumps and membrane permeability contribute to intrinsic antibiotic resistance in Mycobacterium abscessus

Mycobacterium abscessus is a pulmonary pathogen that exhibits intrinsic resistance to antibiotics, but the factors driving this resistance are incompletely understood. Insufficient intracellular drug accumulation could explain broad-spectrum resistance, but whether antibiotics fail to accumulate in M. abscessus and the mechanisms required for drug exclusion remain poorly understood. We measured antibiotic accumulation in M. abscessus using mass spectrometry and found a wide range of drug accumulation across clinically relevant antibiotics. Of these compounds, linezolid accumulates the least, suggesting that inadequate uptake impacts its efficacy. We utilized transposon mutagenesis screening to identify genes that cause linezolid resistance and found multiple transporters that promote membrane permeability or efflux, including an uncharacterized, M. abscessus-specific protein that effluxes linezolid and several chemically related antibiotics. This demonstrates that membrane permeability and drug efflux are critical mechanisms of antibiotic resistance in M. abscessus and suggests that targeting membrane transporters could potentiate the efficacy of certain antibiotics.

Lower or higher oxygenation targets in the intensive care unit: an individual patient data meta-analysis

PURPOSE

Optimal oxygenation targets for patients with acute hypoxemic respiratory failure in the intensive care unit (ICU) are not clearly defined due to substantial variability in design of previous trials. This study aimed to perform a pre-specified individual patient data meta-analysis of the Handling Oxygenation Targets in the ICU (HOT-ICU) and the Handling Oxygenation Targets in coronavirus disease 2019 (COVID-19) (HOT-COVID) trials to compare targeting a partial pressure of arterial oxygen (PaO2) of 8-12 kPa in adult ICU patients, assessing both benefits and harms.

METHODS

We assessed 90-day all-cause mortality and days alive without life support in 90 days using a generalised mixed model. Heterogeneity of treatment effects (HTE) was evaluated in 14 subgroups, and results graded using the Instrument to assess the Credibility of Effect Modification Analyses (ICEMAN).

RESULTS

At 90 days, mortality was 40.4% (724/1792) in the 8 kPa group and 40.9% (733/1793) in the 12 kPa group (risk ratio, 0.99; 95% confidence interval [CI] 0.92-1.07; P = 0.80). No difference was observed in number of days alive without life support. Subgroup analyses indicated more days alive without life support in COVID-19 patients targeting 8 kPa (P = 0.04) (moderate credibility), and lower mortality (P = 0.03) and more days alive without life support (P = 0.02) in cancer-patients targeting 12 kPa (low credibility).

CONCLUSION

This study reported no overall differences comparing a PaO2 target of 8-12 kPa on mortality or days alive without life support in 90 days. Subgroup analyses suggested HTE in patients with COVID-19 (moderate credibility) and cancer (low credibility).

Research progress on high-concentration oxygen therapy after cerebral hemorrhage

Recently, the role of high-concentration oxygen therapy in cerebral hemorrhage has been extensively discussed. This review describes the research progress in high-concentration oxygen therapy after cerebral hemorrhage. High-concentration oxygen therapy can be classified into two treatment methods: hyperbaric and normobaric high-concentration oxygen therapy. Several studies have reported that high-concentration oxygen therapy uses the pathological mechanisms of secondary ischemia and hypoxia after cerebral hemorrhage as an entry point to improve cerebral oxygenation, metabolic rate, cerebral edema, intracranial pressure, and oxidative stress. We also elucidate the mechanisms by which molecules such as Hypoxia-inducible factor 1-alpha (HIF-1α), vascular endothelial growth factor, and erythropoietin (EPO) may play a role in oxygen therapy. Although people are concerned about the toxicity of hyperoxia, combined with relevant literature, the evidence discussed in this article suggests that as long as the duration, concentration, pressure, and treatment interval of patients with cerebral hemorrhage are properly understood and oxygen is administered within the treatment window, it can be effective to avoid hyperoxic oxygen toxicity. Combined with the latest research, we believe that high-concentration oxygen therapy plays an important positive role in injuries and outcomes after cerebral hemorrhage, and we recommend expanding the use of normal-pressure high-concentration oxygen therapy for cerebral hemorrhage.

Growing from common ground: nontuberculous mycobacteria and bronchiectasis

Bronchiectasis and nontuberculous mycobacteria (NTM) are intricately intertwined, with NTM capable of being both a cause and consequence of bronchiectatic disease. This narrative review focuses on the common ground of bronchiectasis and NTM pulmonary disease (NTM-PD) in terms of diagnostic approach, underlying risk factors and treatment strategies. NTM-PD diagnosis relies on a combination of clinical, radiological and microbiological criteria. Although their epidemiology is complicated by detection and reporting biases, the prevalence and pathogenicity of NTM species vary geographically, with Mycobacterium avium complex and Mycobacterium abscessus subspecies most frequently isolated in bronchiectasis-associated NTM-PD. Diagnosis of nodular bronchiectatic NTM-PD should prompt investigation of host factors, including disorders of mucociliary clearance, connective tissue diseases and immunodeficiencies, either genetic or acquired. Treatment of NTM-PD in bronchiectasis involves a multidisciplinary approach and considers the (sub)species involved, disease severity and comorbidities. Current guideline-based antimicrobial treatment of NTM-PD is considered long, cumbersome and unsatisfying in terms of outcomes. Novel treatment regimens and strategies are being explored, including rifampicin-free regimens and inclusion of clofazimine and inhaled antibiotics. Host-directed therapies, such as immunomodulators and cytokine-based therapies, might enhance antimycobacterial immune responses. Optimising supportive care, as well as pathogen- and host-directed strategies, is crucial, highlighting the need for personalised approaches tailored to individual patient needs. Further research is warranted to elucidate the complex interplay between host and mycobacterial factors, informing more effective management strategies.

Treating sleep-disordered breathing of idiopathic pulmonary fibrosis patients with CPAP and nocturnal oxygen treatment. A pilot study : Sleep-disordered breathing treatment in IPF

INTRODUCTION

Sleep-disordered breathing (SDB) is a major comorbidity in idiopathic pulmonary fibrosis (IPF) and is associated with a poor outcome. There is a lack of knowledge regarding the impact of SDB treatment on IPF. We assessed at one year: (1) the effect of CPAP and/or nocturnal oxygen therapy on IPF regarding lung function, blood mediators, and quality of life; (2) adherence to SDB treatment and SDB changes.

METHODOLOGY

This is a prospective study of consecutive newly diagnosed IPF patients initiating anti-fibrotic treatment. Lung function, polysomnography, blood tests and quality of life questionnaires were performed at inclusion and after one year. Patients were classified as obstructive sleep apnoea (OSA), central sleep apnoea (CSA), and sleep-sustained hypoxemia (SSH). SDB therapy (CPAP and/or nocturnal oxygen therapy) was initiated if needed.

RESULTS

Fifty patients were enrolled (36% had OSA, 22% CSA, and 12% SSH). CPAP was started in 54% of patients and nocturnal oxygen therapy in 16%. At one-year, polysomnography found improved parameters, though 17% of patients had to add nocturnal oxygen therapy or CPAP, while 33% presented SDB onset at this second polysomnography. CPAP compliance at one year was 6.74 h/night (SD 0.74). After one year, matrix metalloproteinase-1 decreased in OSA and CSA (p = 0.029; p = 0.027), C-reactive protein in OSA (p = 0.045), and surfactant protein D in CSA group (p = 0.074). There was no significant change in lung function.

CONCLUSIONS

Treatment of SBD with CPAP and NOT can be well tolerated with a high compliance. IPF patients may exhibit SDB progression and require periodic re-assessment. Further studies to evaluate the impact of SDB treatment on lung function and serological mediators are needed.

Automated oxygen titration with non-invasive ventilation in hypoxaemic adults with cardiorespiratory disease: a randomised cross-over trial

BACKGROUND

Closed-loop oxygen control systems automatically adjust the fraction of inspired oxygen (FiO2) to maintain oxygen saturation (SpO2) within a predetermined target range. Their performance with low and high-flow oxygen therapies, but not with non-invasive ventilation, has been established. We compared the effect of automated oxygen on achieving and maintaining a target SpO2 range with nasal high flow (NHF), bilevel positive airway pressure (bilevel) and continuous positive airway pressure (CPAP), in stable hypoxaemic patients with chronic cardiorespiratory disease.

METHODS

In this open-label, three-way cross-over trial, participants with resting hypoxaemia (n=12) received each of NHF, bilevel and CPAP treatments, in random order, with automated oxygen titrated for 10 min, followed by 36 min of standardised manual oxygen adjustments. The primary outcome was the time taken to reach target SpO2 range (92%-96%). Secondary outcomes included time spent within target range and physiological responses to automated and manual oxygen adjustments.

RESULTS

Two participants were randomised to each of six possible treatment orders. During automated oxygen control (n=12), the mean (±SD) time to reach target range was 114.8 (±87.9), 56.6 (±47.7) and 67.3 (±61) seconds for NHF, bilevel and CPAP, respectively, mean difference 58.3 (95% CI 25.0 to 91.5; p=0.002) and 47.5 (95% CI 14.3 to 80.7; p=0.007) seconds for bilevel and CPAP versus NHF, respectively. Proportions of time spent within target range were 68.5% (±16.3), 65.6% (±28.7) and 74.7% (±22.6) for NHF, bilevel and CPAP, respectively.Manually increasing, then decreasing, the FiO2 resulted in similar increases and then decreases in SpO2 and transcutaneous carbon dioxide (PtCO2) with NHF, bilevel and CPAP.

CONCLUSION

The target SpO2 range was achieved more quickly when automated oxygen control was initiated with bilevel and CPAP compared with NHF while time spent within the range across the three therapies was similar. Manually changing the FiO2 had similar effects on SpO2 and PtCO2 across each of the three therapies.

TRIAL REGISTRATION NUMBER

ACTRN12622000433707.

Metformin-associated lactic acidosis: A mini review of pathophysiology, diagnosis and management in critically ill patients

Metformin is a common diabetes drug that may reduce lactate clearance by inhibiting mitochondrial oxidative phosphorylation, leading to metformin-associated lactic acidosis (MALA). As diabetes mellitus is a common chronic metabolic condition found in critically ill patients, pre-existing metformin use can often be found in critically ill patients admitted to the intensive care unit or the high dependency unit. The aim of this narrative mini review is therefore to update clinicians about MALA, and to provide a practical approach to its diagnosis and treatment. MALA in critically ill patients may be suspected in a patient who has received metformin and who has a high anion gap metabolic acidosis, and confirmed when lactate exceeds 5 mmol/L. Risk factors include those that reduce renal elimination of metformin (renal impairment from any cause, histamine-2 receptor antagonists, ribociclib) and excessive alcohol consumption (as ethanol oxidation consumes nicotinamide adenine dinucleotides that are also required for lactate metabolism). Treatment of MALA involves immediate cessation of metformin, supportive management, treating other concurrent causes of lactic acidosis like sepsis, and treating any coexisting diabetic ketoacidosis. Severe MALA requires extracorporeal removal of metformin with either intermittent hemodialysis or continuous kidney replacement therapy. The optimal time to restart metformin has not been well-studied. It is nonetheless reasonable to first ensure that lactic acidosis has resolved, and then recheck the kidney function post-recovery from critical illness, ensuring that the estimated glomerular filtration rate is 30 mL/min/1.73 m2 or better before restarting metformin.

An Innovative Study Focused on Reducing Unnecessary Oxygen Exposure in Pediatric Patients

PURPOSE

In the perioperative period, fractional-inspired oxygen is used at values up to 80% to stay within the safe range, even for a short time. A clear value for the safe range has not been specified, and therefore, clinicians prefer a high oxygen value. This study aims to reduce unnecessary oxygen exposure in pediatrice patients and to provide the optimum fractional inspired oxygen value.

DESIGN

The study was designed as a prospective randomized controlled study, including 139 patients aged 1 to 8 years without comorbidity.

METHODS

Three groups were formed by adjusting the fractional inspired oxygen to 30%, 50%, or 80% intraoperatively. In the intraoperative period, a strict inspired oxygen protocol (hypoxemia threshold was SpO2 < 90) and oxygen reserve index, fractional expired oxygen value, and peripheral oxygen saturation were used to maintain the balance of hypoxemia and hyperoxemia.

FINDINGS

One hundred and nine children were included. The mean oxygen reserve index was significantly lower in the 30% group than in the other groups (0.09 ± 0.05, P < .0001). The mean arterial pressure in the 30% group was significantly lower than the 80% group but within the normal range (78 ± 6 mmHg, P < .003). There was no significant difference between the groups regarding delirium and pain in the recovery unit.

CONCLUSIONS

Due to the known and unknown harmful effects of unnecessary oxygen exposure, it may be time to use optimal oxygen and to fear unnecessary oxygen, not less oxygen. As the next step, we think studies should be conducted with patient groups with lower oxygen concentrations (eg, %21 vs %24 vs %30), more patients, and arterial blood gas monitoring.

Effects of moderate alcohol consumption and hypobaric hypoxia: implications for passengers' sleep, oxygen saturation and heart rate on long-haul flights

BACKGROUND

Passengers on long-haul flights frequently consume alcohol. Inflight sleep exacerbates the fall in blood oxygen saturation (SpO2) caused by the decreased oxygen partial pressure in the cabin. We investigated the combined influence of alcohol and hypobaric hypoxia on sleep, SpO2 and heart rate.

METHODS

Two groups of healthy individuals spent either two nights with a 4-hour sleep opportunity (00:00-04:00 hours) in the sleep laboratory (n=23; 53 m above sea level) or in the altitude chamber (n=17; 753 hPa corresponding to 2438 m above sea level, hypobaric condition). Participants consumed alcohol before one of the nights (mean±SE blood alcohol concentration 0.043±0.003%). The order of the nights was counterbalanced. Two 8-hour recovery nights (23:00-07:00 hours) were scheduled between conditions. Polysomnography, SpO2 and heart rate were recorded.

RESULTS

The combined exposure to alcohol and hypobaric condition decreased SpO2 to a median (25th/75th percentile) of 85.32% (82.86/85.93) and increased heart rate to a median (25th/75th percentile) of 87.73 bpm (85.89/93.86) during sleep compared with 88.07% (86.50/88.49) and 72.90 bpm (70.90/78.17), respectively, in the non-alcohol hypobaric condition, 94.97% (94.59/95.33) and 76.97 bpm (65.17/79.52), respectively, in the alcohol condition and 95.88% (95.72/96.36) and 63.74 bpm (55.55/70.98), respectively, in the non-alcohol condition of the sleep laboratory group (all p<0.0001). Under the combined exposure SpO2 was 201.18 min (188.08/214.42) below the clinical hypoxia threshold of 90% SpO2 compared with 173.28 min (133.25/199.03) in the hypobaric condition and 0 min (0/0) in both sleep laboratory conditions. Deep sleep (N3) was reduced to 46.50 min (39.00/57.00) under the combined exposure compared with both sleep laboratory conditions (alcohol: 84.00 min (62.25/92.75); non-alcohol: 67.50 min (58.50/87.75); both p<0.003).

CONCLUSIONS

The combination of alcohol and inflight hypobaric hypoxia reduced sleep quality, challenged the cardiovascular system and led to extended duration of hypoxaemia (SpO2 <90%).

Hyperoxemia among Pediatric Intensive Care Unit Patients Receiving Oxygen Therapy

Supratherapeutic oxygen levels consistently cause oxygen toxicity in the lungs and other organs. The prevalence and severity of hyperoxemia among pediatric intensive care unit (PICU) patients remain unknown. This was the first study to examine the prevalence and duration of hyperoxemia in PICU patients receiving oxygen therapy. This is a retrospective chart review. This was performed in a setting of 36-bed PICU in a quaternary-care children's hospital. All the patients were children aged <18 years, admitted to the PICU for ≥24 hours, receiving oxygen therapy for ≥12 hours who had at least one arterial blood gas during this time. There was no intervention. Of 5,251 patients admitted to the PICU, 614 were included in the study. On average, these patients received oxygen therapy for 91% of their time in the PICU and remained hyperoxemic, as measured by pulse oximetry, for 65% of their time on oxygen therapy. Patients on oxygen therapy remained hyperoxemic for a median of 38 hours per patient and only 1.1% of patients did not experience any hyperoxemia. Most of the time (87.5%) patients received oxygen therapy through a fraction of inspired oxygen (FiO 2 )-adjustable device. Mean FiO 2 on noninvasive support was 0.56 and on invasive support was 0.37. Mean partial pressure of oxygen (PaO 2 ) on oxygen therapy was 108.7 torr and 3,037 (42.1%) of PaO 2 measurements were >100 torr. Despite relatively low FiO 2 , PICU patients receiving oxygen therapy are commonly exposed to prolonged hyperoxemia, which may contribute to ongoing organ injury.

Pre-oxygenation with high-flow oxygen through the nasopharyngeal airway compared to facemask on carbon dioxide clearance in emergency adults: a prospective randomized non-blinded clinical trial

INTRODUCTION

Before tracheal intubation, it is essential to provide sufficient oxygen reserve for emergency patients with full stomachs. Recent studies have demonstrated that high-flow nasal oxygen (HFNO) effectively pre-oxygenates and prolongs apneic oxygenation during tracheal intubation. Despite its effectiveness, the use of HFNO remains controversial due to concerns regarding carbon dioxide clearance. The air leakage and unknown upper airway obstruction during HFNO therapy cause reduced oxygen flow above the vocal cords, possibly weaken the carbon dioxide clearance.

METHODS

Patients requiring emergency surgery who had fasted < 8 h and not drunk < 2 h were randomly assigned to the high-flow group, who received 100% oxygen at 30-60 L/min through nasopharyngeal airway (NPA), or the mask group, who received 100% oxygen at 8 L/min. PaO2 and PaCO2 were measured immediately before pre-oxygenation (T0), anesthesia induction (T1), tracheal intubation (T2), and mechanical ventilation (T3). The gastric antrum's cross-sectional area (CSA) was measured using ultrasound technology at T0, T1, and T3. Details of complications, including hypoxemia, reflux, nasopharyngeal bleeding, postoperative pulmonary infection, postoperative nausea and vomiting (PONV), and postoperative nasopharyngeal pain, were recorded. The primary outcomes were PaCO2 measured at T1, T2, and T3. The secondary outcomes included PaO2 at T1, T2, and T3, CSA at T1 and T3, and complications happened during this trial.

RESULTS

Pre-oxygenation was administered by high-flow oxygen through NPA (n = 58) or facemask (n = 57) to 115 patients. The mean (SD) PaCO2 was 32.3 (6.7) mmHg in the high-flow group and 34.6 (5.2) mmHg in the mask group (P = 0.045) at T1, 45.0 (5.5) mmHg and 49.4 (4.6) mmHg (P < 0.001) at T2, and 47.9 (5.1) mmHg and 52.9 (4.6) mmHg (P < 0.001) at T3, respectively. The median ([IQR] [range]) PaO2 in the high-flow and mask groups was 404.5 (329.1-458.1 [159.8-552.9]) mmHg and 358.9 (274.0-413.3 [129.0-539.1]) mmHg (P = 0.007) at T1, 343.0 (251.6-428.7 [73.9-522.1]) mmHg and 258.3 (162.5-347.5 [56.0-481.0]) mmHg (P < 0.001) at T2, and 333.5 (229.9-411.4 [60.5-492.4]) mmHg and 149.8 (87.0-246.6 [51.2-447.5]) mmHg (P < 0.001) at T3, respectively. The CSA in the high-flow and mask groups was 371.9 (287.4-557.9 [129.0-991.2]) mm2 and 386.8 (292.0-537.3 [88.3-1651.7]) mm2 at T1 (P = 0.920) and 452.6 (343.7-618.4 [161.6-988.1]) mm2 and 385.6 (306.3-562.0 [105.5-922.9]) mm2 at T3 (P = 0.173), respectively. The number (proportion) of complications in the high-flow and mask groups is shown below: hypoxemia: 1 (1.7%) vs. 9 (15.8%, P = 0.019); reflux: 0 (0%) vs. 0 (0%); nasopharyngeal bleeding: 1 (1.7%) vs. 0 (0%, P = 1.000); pulmonary infection: 4 (6.9%) vs. 3 (5.3%, P = 1.000); PONV: 4 (6.9%) vs. 4 (7.0%, P = 1.000), and nasopharyngeal pain: 0 (0%) vs. 0 (0%).

CONCLUSIONS

Compared to facemasks, pre-oxygenation with high-flow oxygen through NPA offers improved carbon dioxide clearance and enhanced oxygenation prior to tracheal intubation in patients undergoing emergency surgery, while the risk of gastric inflation had not been ruled out.

TRIAL REGISTRATION

This trial was registered prospectively at the Chinese Clinical Research Registry on 26/4/2022 (Registration number: ChiCTR2200059192).

Effects of a lower versus a higher oxygenation target in intensive care unit patients with chronic obstructive pulmonary disease and acute hypoxaemic respiratory failure: a subgroup analysis of a randomised clinical trial

Background

Oxygen supplementation is ubiquitous in intensive care unit (ICU) patients with chronic obstructive pulmonary disease (COPD) and acute hypoxaemia, but the optimal oxygenation target has not been established.

Methods

This was a pre-planned subgroup analysis of the Handling Oxygenation Targets in the ICU (HOT-ICU) trial, which allocated patients with acute hypoxaemia to a lower oxygenation target (partial pressure of arterial oxygen [Pao2] of 8 kPa) vs a higher target (Pao2 of 12 kPa) during ICU admission, for up to 90 days; the allocation was stratified for presence or absence of COPD. Here, we report key outcomes for patients with COPD.

Results

The HOT-ICU trial enrolled 2928 patients of whom 563 had COPD; 277 were allocated to the lower and 286 to the higher oxygenation group. After allocation, the median Pao2 was 9.1 kPa (inter-quartile range 8.7-9.9) in the lower group vs 12.1 kPa (11.2-12.9) in the higher group. Data for arterial carbon dioxide (Paco2) were available for 497 patients (88%) with no between-group difference in time-weighted average; median Paco2 6.0 kPa (5.2-7.2) in the lower group vs 6.2 kPa (5.4-7.3) in the higher group. At 90 days, 122/277 patients (44%) in the lower oxygenation group had died vs 132/285 patients (46%) in the higher (relative risk 0.98; 95% confidence interval 0.82-1.17; P=0.67). No statistically significant differences were found in any secondary outcome.

Conclusions

In ICU patients with COPD and acute hypoxaemia, a lower vs a higher oxygenation target did not reduce mortality. There were no between-group differences in Paco2 or in secondary outcomes.

Clinical trial registration

NCT03174002, EudraCT number 2017-000632-34.

Applying Noninvasive Ventilation in Treatment of Acute Exacerbation of COPD Using Evidence-Based Interprofessional Clinical Practice

When administered as first-line intervention to patients admitted with acute hypercapnic respiratory failure secondary to COPD exacerbation in conjunction with guideline-recommended therapies, noninvasive ventilation (NIV) has been shown to reduce mortality and endotracheal intubation. Opportunities to increase uptake of NIV continue to exist despite inclusion of this therapy in clinical guidelines. Identifying patients appropriate for NIV, and subsequently providing close monitoring to determine an improvement in clinical condition involves a team consisting of physician, nurse, and respiratory therapist in institutions that successfully implement NIV. We describe to our knowledge the first known evidence-based algorithm speaking to initiation, titration, monitoring, and weaning of NIV in treatment of acute exacerbation of COPD that incorporates the necessary interprofessional collaboration among physicians, nurses, and respiratory therapists caring for these patients.

Effect of automated titration of oxygen on time spent in a prescribed oxygen saturation range in adults in the ICU after cardiac surgery

Objective

The objective of this study was to determine whether automated titration of the fraction of inspired oxygen (FiO2) increases the time spent with oxygen saturation (SpO2) within a predetermined target SpO2 range compared with manually adjusted high-flow oxygen therapy in postoperative cardiac surgical patients managed in the intensive care unit (ICU).

Design

Single-centre, open-label, randomised clinical trial.

Setting

Tertiary centre ICU.

Participants

Recently extubated adults following elective cardiac surgery who required supplemental oxygen.

Interventions

Automatically adjusted FiO2 (using an automated oxygen control system) compared with manual FiO2 titration, until cessation of oxygen therapy, ICU discharge, or 24 h (whichever was sooner).

Main outcome measures

The primary outcome was the proportion of time receiving oxygen therapy with the SpO2 in a SpO2 target range of 92-96 %.

Results

Among 65 participants, the percentage of time per patient spent in the target SpO2 range was a median of 97.7 % (interquartile range: 87.9-99.2 %) and 91.3 % (interquartile range: 77.1-96.1 %) in the automated (n = 28) and manual (n = 28) titration groups, respectively. The estimated effect of automated FiO2, compared to manual FiO2 titration, was to increase the percentage of time spent in the target range by a median of 4.8 percentage points (95 % confidence interval: 1.6 to 10.3 percentage points, p = 0.01).

Conclusion

In patients recently extubated after cardiac surgery, automated FiO2 titration significantly increased time spent in a target SpO2 range of 92-96 % compared to manual FiO2 titration.

Implementing High-Flow Nasal Oxygen Therapy in Medical Wards: A Scoping Review to Understand Hospital Protocols and Procedures

Acute hypoxemic respiratory failure (ARF) is a common cause for hospital admission. High-flow nasal oxygen (HFNO) is increasingly used as a first-line treatment for patients with ARF, including in medical wards. Clinical guidance is crucial when providing HFNO, and health services use local health guidance documents (LHGDs) to achieve this. It is unknown what hospital LHGDs recommend regarding ward administration of HFNO. This study examined Australian hospitals' LHGDs regarding ward-based HFNO administration to determine content that may affect safe delivery. A scoping review was undertaken on 2 May 2022 and updated on 29 January 2024 to identify public hospitals' LHGDs regarding delivery of HFNO to adults with ARF in medical wards in two Australian states. Data were extracted and analysed regarding HFNO initiation, monitoring, maintenance and weaning, and management of clinical deterioration. Of the twenty-six included LHGDs, five documents referenced Australian Oxygen Guidelines. Twenty LHGDs did not define a threshold level of hypoxaemia where HFNO use was recommended over conventional oxygen therapy. Thirteen did not provide target oxygen saturation ranges whilst utilising HFNO. Recommendations varied regarding maximal levels of inspired oxygen and flow rates in the medical ward. Eight LHGDs did not specify any system to identify and manage deteriorating patients. Five LHGDs did not provide guidance for weaning patients from HFNO. There was substantial variation in the LHGDs regarding HFNO care for adult patients with ARF in Australian hospitals. These findings have implications for the delivery of high-quality, safe clinical care in hospitals.

New perspective crosslinking electrochemistry and other research fields: beyond electrochemical reactors

Over the years, electrochemical reactors have evolved significantly, with modern reactors now able to achieve a high current density and power output in compact sizes. This leap in performance has not only greatly accelerated the rate of electrochemical reactions but also had a broader impact on the environment. Traditional research perspectives, focused primarily on the internal working systems of reactors, possibly overlook the potential of electrochemical systems in regulating their surrounding environment. A novel research perspective considering the interaction between electrochemical processes and their environmental context as a unified subject of study has gradually emerged alongside the dramatic development of electrochemical techniques. This viewpoint introduces a paradigm shift: electrochemical reactors are not isolated entities but rather are integral parts that interact with their surroundings. Correspondingly, this calls for an innovative research methodology that goes beyond studying the electrochemical processes in isolation. Rather, it integrates the design of the electrochemical system with its specific application environment, ensuring seamless integration for optimal performance under various practical conditions. Therefore, performance metrics should include not only the basic parameters of the electrochemical reactions but also the adaptability of the electrochemical system in real-world scenarios beyond the laboratory. By focusing on environmental integration and application-driven design, the applications of electrochemical technology can be more effectively leveraged. This perspective is exemplified by an electrochemical system based on coupled cathodic oxygen reduction and anodic oxygen evolution reactions. By adopting this new research paradigm, the applications of this electrochemical system can be extended to fields like medical treatment, food science, and microbial fermentation, with an emphasis on tailored designs for these specific application fields. This comprehensive and systematic new research approach aims to fully explore the potential applications of electrochemical technology and foster interdisciplinary collaboration in the electrochemical field.

Factors associated with intubation in patients with acute hypoxaemic respiratory failure treated with high-flow nasal cannula oxygen therapy: A prospective, observational study

BACKGROUND

High-flow nasal cannula (HFNC) oxygen is an alternative to conventional oxygen in acute hypoxaemic respiratory failure. Some patients require intubation, with a risk of delay; thus, early predictors may identify those requiring earlier intubation. The "ROX" index (ratio of pulse oximetry/fraction of inspired oxygen to respiratory rate) predicts intubation in patients with pneumonia treated with HFNC therapy, but this index has not been validated in non-pneumonia causes of acute hypoxaemic respiratory failure.

AIM/OBJECTIVE

The aim of this study was to identify factors associated with intubation in a heterogeneous group of patients with acute hypoxaemic respiratory failure treated with HFNC oxygen.

METHODS

This prospective observational study was undertaken in an Australian tertiary intensive care unit and included patients over 18 y of age with acute hypoxaemic respiratory failure who were treated with oxygen via HFNC. Vital signs and arterial blood gases were recorded prospectively at baseline and regular prespecified intervals for 48 h after HFNC initiation. Multivariate logistic regression was used to identify the factors associated with intubation.

RESULTS

Forty-three patients were included (N = 43). The multivariate factors associated with intubation were admission Sequential Organ Failure Assessment score (odds ratio [OR]: 1.94 [95% confidence interval {CI}: 1.06-3.57]; p = 0.032) and Pneumonia Severity Index (OR: 0.95 [95% CI: 0.90-0.99]; p = 0.034). The ROX index was not independently associated with intubation when adjusted for Sequential Organ Failure Assessment score (OR: 0.71 [95% CI: 0.47-1.06]; p = 0.09). There was no difference in mortality between patients intubated early (<24 h) compared to those intubated late.

CONCLUSIONS

Intubation was associated with admission Sequential Organ Failure Assessment score and Pneumonia Severity Index. The ROX index was not associated with intubation when adjusted for admission Sequential Organ Failure Assessment score. Outcomes were similar irrespective of whether patients were intubated late rather than early.

Assessing the safety of physical rehabilitation in critically ill patients: a Delphi study

BACKGROUND

Physical rehabilitation of critically ill patients is implemented to improve physical outcomes from an intensive care stay. However, before rehabilitation is implemented, a risk assessment is essential, based on robust safety data. To develop this information, a uniform definition of relevant adverse events is required. The assessment of cardiovascular stability is particularly relevant before physical activity as there is uncertainty over when it is safe to start rehabilitation with patients receiving vasoactive drugs.

METHODS

A three-stage Delphi study was carried out to (a) define adverse events for a general ICU cohort, and (b) to define which risks should be assessed before physical rehabilitation of patients receiving vasoactive drugs. An international group of intensive care clinicians and clinician researchers took part. Former ICU patients and their family members/carers were involved in generating consensus for the definition of adverse events. Round one was an open round where participants gave their suggestions of what to include. In round two, participants rated their agreements with these suggestions using a five-point Likert scale; a 70% consensus agreement threshold was used. Round three was used to re-rate suggestions that had not reached consensus, whilst viewing anonymous feedback of participant ratings from round two.

RESULTS

Twenty-four multi-professional ICU clinicians and clinician researchers from 10 countries across five continents were recruited. Average duration of ICU experience was 18 years (standard deviation 8) and 61% had publications related to ICU rehabilitation. For the adverse event definition, five former ICU patients and one patient relative were recruited. The Delphi process had a 97% response rate. Firstly, 54 adverse events reached consensus; an adverse event tool was created and informed by these events. Secondly, 50 risk factors requiring assessment before physical rehabilitation of patients receiving vasoactive drugs reached consensus. A second tool was created, informed by these suggestions.

CONCLUSIONS

The adverse event tool can be used in studies of physical rehabilitation to ensure uniform measurement of safety. The risk assessment tool can be used to inform clinical practise when risk assessing when to start rehabilitation with patients receiving vasoactive drugs. Trial registration This study protocol was retrospectively registered on https://www.researchregistry.com/ (researchregistry2991).

Effect of postoperative oxygen therapy regimen modification on oxygenation in patients with acute type A aortic dissection

Objective

In this study, we investigated the effect of various oxygen therapy regimens on oxygenation in patients with acute type A aortic dissection (AAD).

Methods

A quasi-randomized controlled trial was conducted, in which patients with AAD hospitalized for surgery from June to September 2021 were assigned to the control group (patients received conventional oxygen therapy after postoperative mechanical ventilation, weaning, and extubation) and those who were admitted from October to December 2021 were assigned to the observation group [patients underwent optimally adjusted therapy based on the treatment of the control group, which mainly included prioritized elevation of positive end-expiratory pressure (PEEP) and restricted use of the fraction of inspired oxygen (FiO2)].The postoperative oxygenation index, blood gas analysis, and duration of mechanical ventilation were compared between the two groups.

Results

There were significant differences in oxygenation observed at 2 h postoperatively between the groups. 12, 24, and 72 h postoperatively, the oxygenation index varied significantly between the two groups. There were statistically significant differences in the time effects of the oxygenation index and PaO2 between the two groups, as well as significant differences in the length of stay in the intensive care unit.

Conclusion

For the postoperative care of patients with AAD, it is suggested that the minimum FiO2 required for oxygenation of patients be maintained. In addition, it is possible to enhance PEEP as a priority when PaO2 is low.

Conservative versus liberal oxygen therapy for intensive care unit patients: meta-analysis of randomized controlled trials

BACKGROUND

It remains unclear whether conservative oxygen therapy (COT) or liberal oxygen therapy (LOT) is more beneficial to the clinical outcomes of intensive care unit (ICU) patients. We systematically reviewed the efficacy and safety of conservative versus liberal oxygen therapy for ICU patients.

METHODS

We systematically searched PubMed, Embase, Web of Science, Scopus, Cochrane Central Register of Controlled Trials, ClinicalTrials.gov, MedRxiv, and BioRxiv for reports on randomized controlled trials (RCTs) that compared the effects of COT versus LOT on the clinical outcomes of ICU patients published in English before April 2024. The primary outcome was the mortality rate, secondary outcomes included ICU and hospital length of stay, days free from mechanical ventilation support (MVF), vasopressor-free time (VFT), and adverse events.

RESULTS

In all, 13 RCTs involving 10,632 patients were included in analyses. Meta-analysis showed COT did not reduce mortality at 30-day (risk ratio [RR] = 1.01, 95% confidence interval [CI] 0.94 to 1.09, I2 = 42%, P = 0.78), 90-day (RR = 1.01, 95% CI 0.95 to 1.08, I2 = 9%, P = 0.69), or longest follow-up (RR = 1.00, 95% CI 0.95 to 1.06, I2 = 22%, P = 0.95) compared to LOT in ICU patients. In subgroup analyses, no significant difference was observed between the two groups in terms of the different ICU, baseline P/F, and actual PaO2. In addition, COT did not affect ICU length of stay, hospital length of stay, or VFT, it only affected MVF days.

CONCLUSIONS

COT did not reduce all-cause mortality in ICU patients. Further RCTs are urgently needed to confirm the impact of COT strategy on specific populations.

Non-tuberculous mycobacterial pulmonary infection presenting in a patient with unilateral pulmonary artery agenesis

People who have structural or developmental lung disease are more likely to develop non-tuberculous mycobacterial infections. We present the case of a young man in his 30s who had unilateral pulmonary artery agenesis on the right side and presented with a 6-month history of productive cough and fever. His CT scan showed nodular and cavitating lesions on the right side, and sputum analysis confirmed infection with Mycobacterium chimaera He had to undergo modifications in his treatment, including a change from rifampicin to rifabutin due to drug interactions and his amikacin had to be stopped due to signs of vestibular toxicity. Using a multidisciplinary approach, we were able to formulate an appropriate drug regimen for him, and he is now under regular follow-up with infectious diseases and respiratory medicine.

Assessment of hypoxemia among young adults with sickle cell anaemia in steady state in southwestern Nigeria: a crosssectional study

OBJECTIVES

Hypoxia is a known feature of sickle cell anaemia (SCA) which results from chronic anaemia and recurrent vaso-occlusive crisis (VOC) which can cause tissue ischaemia that leads to an end organ damage. The hallmark of SCA is chronic anaemia and recurrent vaso-occlusive crisis. The aim of this study is to compare the oxygen saturation of sickle cell anaemic individuals with the normal haemoglobin type (Hb AA) control and also to determine the prevalence of hypoxemia among SCA.

RESULTS

Two-hundred and twenty-two (136 Hb SS and 86 Hb AA) participated in the study. The mean ± SD of age (years), oxygen saturation (%) and pulse rate (bpm) of participants with sickle cell anaemia and Hb AA control were 21.85 ± 3.04 and 22.14 ± 3.18 (t = 0.701, p = 0.436), 95.21 ± 3.02 and 98.07 ± 0.81 (t=-8.598, p < 0.0001) and 77.10 ± 9.28 and 73.16 ± 8.52 (t = 3.173, p = 0.002) respectively. The prevalence of hypoxemia among SCA participants was 47.1%. Prevalence of hypoxemia in males with SCA was 60.9% while 39.1% of the females had hypoxemia.

Oxygenation During Venoarterial Extracorporeal Membrane Oxygenation: Physiology, Current Evidence, and a Pragmatic Approach to Oxygen Titration

OBJECTIVES

This review aims to: 1) identify the key circuit and patient factors affecting systemic oxygenation, 2) summarize the literature reporting the association between hyperoxia and patient outcomes, and 3) provide a pragmatic approach to oxygen titration, in patients undergoing peripheral venoarterial extracorporeal membrane oxygenation (ECMO).

DATA SOURCES

Searches were performed using PubMed, SCOPUS, Medline, and Google Scholar.

STUDY SELECTION

All observational and interventional studies investigating the association between hyperoxia, and clinical outcomes were included, as well as guidelines from the Extracorporeal Life Support Organization.

DATA EXTRACTION

Data from relevant literature was extracted, summarized, and integrated into a concise narrative review. For ease of reference a summary of relevant studies was also produced.

DATA SYNTHESIS

The extracorporeal circuit and the native cardiorespiratory circuit both contribute to systemic oxygenation during venoarterial ECMO. The ECMO circuit's contribution to systemic oxygenation is, in practice, largely determined by the ECMO blood flow, whereas the native component of systemic oxygenation derives from native cardiac output and residual respiratory function. Interactions between ECMO outflow and native cardiac output (as in differential hypoxia), the presence of respiratory support, and physiologic parameters affecting blood oxygen carriage also modulate overall oxygen exposure during venoarterial ECMO. Physiologically those requiring venoarterial ECMO are prone to hyperoxia. Hyperoxia has a variety of definitions, most commonly Pa o2 greater than 150 mm Hg. Severe hypoxia (Pa o2 > 300 mm Hg) is common, seen in 20%. Early severe hyperoxia, as well as cumulative hyperoxia exposure was associated with in-hospital mortality, even after adjustment for disease severity in both venoarterial ECMO and extracorporeal cardiopulmonary resuscitation. A pragmatic approach to oxygenation during peripheral venoarterial ECMO involves targeting a right radial oxygen saturation target of 94-98%, and in selected patients, titration of the fraction of oxygen in the mixture via the air-oxygen blender to target postoxygenator Pa o2 of 150-300 mm Hg.

CONCLUSIONS

Hyperoxia results from a range of ECMO circuit and patient-related factors. It is common during peripheral venoarterial ECMO, and its presence is associated with poor outcome. A pragmatic approach that avoids hyperoxia, while also preventing hypoxia has been described for patients receiving peripheral venoarterial ECMO.

Acute Pancreatitis during and after Pregnancy: A Review

During pregnancy and in the post-partum period, several diseases may arise or become exacerbated. Acute pancreatitis is an inflammatory disease with an increasing incidence in Western countries. The incidence of acute pancreatitis during pregnancy is not different with respect to the general population, but this incidence increases in the first 2 years after delivery. Biliary sludge and stones are the most frequent aetiologies, followed by hypertriglyceridemia. Taking care of the mother and foetus through a potentially severe disease requires a team consisting of an obstetrician, a gastroenterologist, an anaesthesiologist, and a surgeon. It is necessary to monitor the health of the foetus/child and the mother during pregnancy, childbirth, and puerperium. The management of this care depends on the systemic and local complications, the severity of the acute pancreatitis, and the trimester of pregnancy. Some diagnostic tools and many drugs are not safe for foetuses, while interventional endoscopy and surgery have limitations and can only be used after an accurate evaluation of benefit/risk ratios. Despite these limitations, maternal mortality due to acute pancreatitis is low during pregnancy, mainly thanks to multidisciplinary approaches for these patients. A careful diet to prevent obesity, alcohol abstinence, routine serum triglyceride control, and breastfeeding for at least three months may prevent acute pancreatitis during and after pregnancy.

Acid base and metabolic parameters of the umbilical cord blood and cerebral oxygenation immediately after birth

Objective

Aim was to investigate whether acid-base and metabolic parameters obtained from arterial umbilical cord blood affect cerebral oxygenation after birth in preterm neonates with respiratory support and in term neonates without respiratory support.

Study design

This was a post-hoc analysis of secondary outcome parameters of a prospective observational study including preterm neonates with and term neonates without respiratory support. Non-asphyxiated neonates with cerebral oxygenation measured with near-infrared spectroscopy during the first 15 min and with blood gas analyses from arterial umbilical cord blood were included. Arterial oxygen saturation (SpO2) and heart rate (HR) were monitored with pulse oximetry. Potential correlations were investigated between acid-base and metabolic parameters (pH-value, bicarbonate, base-excess, and lactate) and crSO2/cFTOE 5 min after birth.

Results

Seventy-seven neonates were included: 14 preterm neonates with respiratory support (mean gestational age [GA] 31.4 ± 4.1 weeks; mean birth weight [BW] 1,690 ± 640 g) and 63 term neonates without respiratory support (GA 38.7 ± 0.8 weeks; BW 3,258 ± 443 g). Mean crSO2 5 min after birth was 44.0% ± 24.2% in preterm and 62.2% ± 20.01% in term neonates. Mean cFTOE 5 min after birth was 0.46 ± 0.06 in preterm and 0.27 ± 0.19 in term neonates. In preterm neonates with respiratory support higher lactate was significantly associated with lower crSO2 and SpO2 and tended to be associated with higher cFTOE. In term neonates without respiratory support no significant correlations were found.

Conclusion

In non-asphyxiated preterm neonates with respiratory support, lactate levels were negatively associated with crSO2 and SpO2, whereas in term neonates without respiratory support no associations were observed.

Diagnosis of cystic lung diseases: a position statement from the UK Cystic Lung Disease Rare Disease Collaborative Network

BACKGROUND

Rare cystic lung diseases are increasingly recognised due the wider application of CT scanning making cystic lung disease management a growing part of respiratory care. Cystic lung diseases tend to have extrapulmonary features that can both be diagnostic but also require surveillance and treatment in their own right. As some of these diseases now have specific treatments, making a precise diagnosis is crucial. While Langerhans cell histiocytosis, Birt-Hogg-Dubé syndrome, lymphoid interstitial pneumonia and lymphangioleiomyomatosis are becoming relatively well-known diseases to respiratory physicians, a targeted and thorough workup improves diagnostic accuracy and may suggest other ultrarare diseases such as light chain deposition disease, cystic pulmonary amyloidosis, low-grade metastatic neoplasms or infections. In many cases, diagnostic information is overlooked leaving uncertainty over the disease course and treatments.

AIMS

This position statement from the Rare Disease Collaborative Network for cystic lung diseases will review how clinical, radiological and physiological features can be used to differentiate between these diseases.

NARRATIVE

We highlight that in many cases a multidisciplinary diagnosis can be made without the need for lung biopsy and discuss where tissue sampling is necessary when non-invasive methods leave diagnostic doubt. We suggest an initial workup focusing on points in the history which identify key disease features, underlying systemic and familial diseases and a clinical examination to search for connective tissue disease and features of genetic causes of lung cysts. All patients should have a CT of the thorax and abdomen to characterise the pattern and burden of lung cysts and extrapulmonary features and also spirometry, gas transfer and a 6 min walk test. Discussion with a rare cystic lung disease centre is suggested before a surgical biopsy is undertaken.

CONCLUSIONS

We suggest that this focused workup should be performed in all people with multiple lung cysts and would streamline referral pathways, help guide early treatment, management decisions, improve patient experience and reduce overall care costs. It could also potentially catalyse a national research database to describe these less well-understood and unidentified diseases, categorise disease phenotypes and outcomes, potentially leading to better prognostic data and generating a stronger platform to understand specific disease biology.

Disseminated Mycobacterium abscessus with endocarditis

We present an uncommon case of endocarditis caused by Mycobacterium abscessus in an immunocompetent patient following a caesarean section. We discuss her turbulent admission course leading to her diagnosis following persistent M. abscessus bacteraemia, medical and surgical management, including a splenectomy and valve resection and repair, and subsequent prolonged course of combination antimicrobials for 24 months post valve surgery. The patient is alive 9 months after completing her treatment and 36 months after her valve surgery. We emphasise the importance of a multidisciplinary team approach in the management of such a complex case.

A Convenient and Effective Preoxygenation Technique for Prolonging Deep Inspiration Breath-Hold Duration With a Venturi Mask With a 50% Oxygen Concentration

PURPOSE

Voluntary deep inspiration breath-hold (DIBH) is commonly used in radiation therapy (RT), but the short duration of a single breath-hold, estimated to be around 20 to 40 seconds, is a limitation. This prospective study aimed to assess the feasibility and safety of using a simple preoxygenation technique with a Venturi mask to prolong voluntary DIBH.

METHODS AND MATERIALS

The study included 33 healthy volunteers and 21 RT patients. Preoxygenation was performed using a Venturi mask with a 50% oxygen concentration. Paired t tests compared the duration of a single DIBH in room air and after 5, 15, and 30 minutes of preoxygenation in healthy volunteers. Sustainability of breath-hold and tolerability of heart rate and blood pressure were assessed for multiple DIBH durations in both volunteers and patients.

RESULTS

In healthy volunteers, a 15-minute preoxygenation significantly prolonged the duration of a single DIBH by 24.95 seconds compared with 5-minute preoxygenation (89 ± 27.76 vs 113.95 ± 30.63 seconds; P < .001); although there was a statistically significant increase in DIBH duration after 30-minute preoxygenation, it was only extended by 4.95 seconds compared with 15-minute preoxygenation (113.95 ± 30.63 vs 118.9 ± 29.77 seconds; P < .01). After 15-minute preoxygenation, a single DIBH lasted over 100 seconds in healthy volunteers and over 80 seconds in RT patients, with no significant differences among 6 consecutive cycles of DIBH. Furthermore, there were no significant differences in heart rate or blood pressure after DIBHs, including DIBH in room air and 6 consecutive DIBHs after 15-minute preoxygenation (all P > .05).

CONCLUSIONS

Preoxygenation with a 50% oxygen concentration for 15 minutes effectively prolongs the duration of 6 cycles of DIBH both in healthy volunteers and RT patients. The utilization of a Venturi mask to deliver 50% oxygen concentration provides a solution characterized by its convenience, good tolerability, and effectiveness.

Acute Pancreatitis Induced by COVID-19 Vaccine: A Systematic Review

Acute pancreatitis, marked by sudden inflammation of the pancreas, presents a complex spectrum of causative factors including gallstone obstruction, alcohol abuse, and viral infections. Recent studies have illuminated the emergence of vaccine-induced acute pancreatitis, notably associated with COVID-19 vaccinations, presenting diverse mechanisms ranging from direct viral-mediated injury to autoimmune reactions. Understanding this link is pivotal for public health, yet challenges persist in identifying and managing cases post-vaccination. Comprehensive literature reviews employing the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement outline the potential pathways and mechanisms leading to vaccine-induced pancreatitis, emphasizing the need for deeper investigations into underlying health conditions and modifications to vaccine components. Notably, the rare occurrences of vaccine-induced pancreatitis extend beyond COVID-19 vaccines, with reports also documenting associations with measles, mumps, and rubella (MMR), human papillomavirus (HPV), and other viral vaccinations. Mechanistically, hypotheses such as molecular mimicry and immunologic injury have been proposed, necessitating ongoing vigilance and exploration. Regulatory agencies play a crucial role in monitoring and communicating vaccine safety concerns, emphasizing transparency to address potential risks and maintain public trust. Understanding and communicating these rare adverse events with transparency remain integral for informed vaccination policies and to allay concerns surrounding vaccine safety.

Effect of a lower target oxygen saturation range on the risk of hypoxaemia and elevated NEWS2 scores at a university hospital: a retrospective study

BACKGROUND

The optimal target oxygen saturation (SpO2) range for hospital inpatients not at risk of hypercapnia is unknown. The objective of this study was to assess the impact on oxygen usage and National Early Warning Score 2 (NEWS2) of changing the standard SpO2 target range from 94-98% to 92-96%.

METHODS

In a metropolitan UK hospital, a database of electronic bedside SpO2 measurements, oxygen prescriptions and NEWS2 records was reviewed. Logistic regression was used to compare the proportion of hypoxaemic SpO2 values (<90%) and NEWS2 records ≥5 in 2019, when the target SpO2 range was 94-98%; with 2022, when the target range was 92-96%.

RESULTS

In 2019, 218 of 224 936 (0.10%) observations on room air and 162 of 11 328 (1.43%) on oxygen recorded an SpO2 <90%, and in 2022, 251 of 225 970 (0.11%) and 233 of 12 845 (1.81%), respectively (risk difference 0.04%, 95% CI 0.02% to 0.07%). NEWS2 ≥5 was observed in 3009 of 236 264 (1.27%) observations in 2019 and 4061 of 238 815 (1.70%) in 2022 (risk difference 0.43%, 0.36% to 0.50%; p<0.001). The proportion of patients using supplemental oxygen with hyperoxaemia (SpO2 100%) was 5.4% in 2019 and 3.9% in 2022 (OR 0.71, 0.63 to 0.81; p<0.001).

DISCUSSION

The proportion of observations with SpO2 <90% or NEWS2 ≥5 was greater with the 92-96% range; however, absolute differences were very small and of doubtful clinical relevance, in contrast to hyperoxaemia for which the proportion was markedly less in 2022. These findings support proposals that the British Thoracic Society oxygen guidelines could recommend a lower target SpO2 range.

Variability of oxygen requirements in critically ill COVID-19 patients

Background

The global scarcity of medical oxygen has proven to be catastrophic during the surges in COVID-19 cases over the past two years, with the heaviest burden felt in low- and middle-income countries. Despite its criticality, data and analyses of oxygen consumption, even for typical clinical cases, are missing. Consequently, planning oxygen needs, particularly with variable surges in COVID-19 cases, has presented a substantial challenge to policymakers and hospital decision-makers.

Methods

We performed a sub-analysis of the COVID-19 Critical Care Consortium database assessing the oxygen consumption requirements of COVID-19 patients admitted to intensive care units between February 2020 and October 2021. We calculated descriptive statistics for oxygen flow-rates, stratified by oxygen supplementation method, and developed a multi-state model for estimating the frequency, therapy duration, probability of transition, and number of oxygen therapy modes per patient.

Results

Overall, 12 429 patients from 35 countries received oxygen support on at least one day of their hospitalisation. Of the patients with measurable flow rates, 6142 received invasive mechanical ventilation, 838 received high-flow nasal oxygen, and 257 received both modalities. The median flow rate for mechanical ventilation was 3.2 L per minute (interquartile range (IQR) = 2.0-4.9), with a median duration of 12 days (IQR = 6-24), while the median flow rate for high-flow nasal cannula was 40 L per minute (IQR = 15-55), with a median duration of three days (IQR = 2-6).

Conclusions

Oxygen consumption among critical COVID-19 patients varies by mode of delivery (invasive ventilation vs high-flow nasal cannula), across patients, and over treatment duration. Therefore, it is essential that health facilities routinely monitor oxygen utilization to better inform oxygen delivery system design and regular supply planning.

Registration

ClinicalTrials.gov: CTG2021-01 ACTRN12620000421932.

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.

Impact of Concurrent Use of N95 and Surgical Masks on Peripheral Oxygen Saturation and Heart Rate Frequency-A Prospective Study during the COVID-19 Outbreak

Background and Objectives: The COVID-19 outbreak has necessitated the prolonged use of N95 facemasks in addition to traditional surgical facemasks by healthcare workers. The aim of this study was to investigate the effect of wearing N95 facemasks in addition to surgical facemasks on peripheral oxygen saturation (SpO2) and heart rate (HR) among dental professionals during routine care. Materials and Methods: This prospective study compared SpO2 and HR between dental providers wearing N95 + surgical facemasks vs. wearing a surgical facemask only. SpO2 and HR were recorded using a portable pulse oximeter before wearing the facemask (T0); at 30 min (T1); at 1 h (T2); and at the end of clinical activity (T3). Inter-group and intra-group differences were assessed with independent t tests and repeated measures ANOVA, respectively. Results: A total of 88 participants (57 wearing N95 + surgical facemasks, and 31 wearing a surgical facemask only) completed the study. The two groups did not statistically differ in SpO2 at different timepoints nor showed any intra-group differences. The participants wearing N95 + surgical facemasks exhibited a statistically higher HR at T0 (p = 0.007), T2 (p = 0.010), and T3 (p = 0.014) compared to those wearing a surgical facemask only. A statistically significant decrease was observed in HR between T0 and T3 in those wearing N95 + surgical facemasks (p = 0.012). No intra-group differences were seen in HR over time in those wearing a surgical facemask only. Conclusions: The continuous use of an N95 in addition to a surgical facemask did not show any significant effects in SpO2 during routine care; however, the concurrent use of an N95 and a surgical facemask seemed to be accompanied by a decrease in HR, although the values remained within the normal range.

Innovative Predictive Approach towards a Personalized Oxygen Dosing System

Despite the large impact chronic obstructive pulmonary disease (COPD) that has on the population, the implementation of new technologies for diagnosis and treatment remains limited. Current practices in ambulatory oxygen therapy used in COPD rely on fixed doses overlooking the diverse activities which patients engage in. To address this challenge, we propose a software architecture aimed at delivering patient-personalized edge-based artificial intelligence (AI)-assisted models that are built upon data collected from patients' previous experiences along with an evaluation function. The main objectives reside in proactively administering precise oxygen dosages in real time to the patient (the edge), leveraging individual patient data, previous experiences, and actual activity levels, thereby representing a substantial advancement over conventional oxygen dosing. Through a pilot test using vital sign data from a cohort of five patients, the limitations of a one-size-fits-all approach are demonstrated, thus highlighting the need for personalized treatment strategies. This study underscores the importance of adopting advanced technological approaches for ambulatory oxygen therapy.

Challenges and knowledge gaps in the management of non-tuberculous mycobacterial pulmonary disease in sub-Saharan African countries with a high tuberculosis burden: a scoping review

INTRODUCTION

In sub-Saharan African (SSA) countries endemic for tuberculosis (TB), previous TB is a significant risk factor for non-tuberculous mycobacterial pulmonary disease (NTM-PD). The deployment of GeneXpert MTB/RIF in pulmonary TB diagnostic work-up regularly identifies symptomatic patients with a positive smear microscopy but negative GeneXpert, indicative of NTM presence. This scoping review outlines recent evidence for NTM-PD diagnosis and management in SSA.

OBJECTIVE

The review's objective was to outline the risk factors, available diagnostics, management options and outcomes of NTM-PD in high-burden TB settings in SSA using the population-concept-context framework.

DESIGN AND DATA SOURCES

We searched existing literature from PubMed, Web of Science, African Journals Online, Google Scholar and grey literature. Studies published between January 2005 and December 2022 were retained. Data were extracted into Rayyan software and Mendeley and summarised using Excel.

RESULTS

We identified 785 potential articles, of which 105 were included in the full-text review, with 7 papers retained. Included articles used international criteria for diagnosing NTM-PD. Multiple papers were excluded due to non-application of the criteria, suggesting challenging application in the SSA setting. Identified risk factors include previous TB, smoking and mining. Most commonly, chest radiography and not CT was used for the radiological diagnosis of PD, which may miss early changes related to NTM-PD. Molecular methods for NTM species identification were employed in research settings, usually at referral centres, but were unavailable for routine care. Most studies did not report a standardised approach to treatment and they were not offered treatment for the specific disease, marking a lack of guidance in treatment decision-making. When treatment was provided, the outcome was often not reported due to the lack of implementation of standardised outcome definitions.

CONCLUSIONS

These outlined challenges present a unique opportunity for researchers to undertake further studies in NTM-PD and proffer solutions more applicable to SSA.

The association between high-oxygen saturation and prognosis for intracerebral hemorrhage

BACKGROUND

Concerns about the adverse effects of excessive oxygen have grown over the years. This study investigated the relationship between high oxygen saturation and short-term prognosis of patients with spontaneous intracerebral hemorrhage (sICH) after liberal use of oxygen.

METHODS

This retrospective cohort study collected data from the Medical Information Mart for Intensive Care III (MIMIC-III) database (ICU cohort) and a tertiary stroke center (general ward cohort). The data on pulse oximetry-derived oxygen saturation (SpO2) during the first 24 h in ICU and general wards were respectively extracted.

RESULTS

Overall, 1117 and 372 patients were included in the ICU and general ward cohort, respectively. Among the patients from the ICU cohort, a spoon-shaped association was observed between minimum SpO2 and the risk of in-hospital mortality (non-linear P<0.0001). In comparison with minimum SpO2 of 93-97%, the minimum SpO2>97% was associated with a significantly higher risk of in-hospital mortality after adjustment for confounders. Sensitivity analysis conducted using propensity score matching did not change this significance. The same spoon-shaped association between minimum SpO2 and the risk of in-hospital mortality was also detected for the general ward cohort. In comparison with the group with 95-97% SpO2, the group with SpO2>97% showed a stronger association with, but non-significant risk for, in-hospital mortality after adjustment for confounders. The time-weighted average SpO2>97% was associated significantly with in-hospital mortality in both cohorts.

CONCLUSION

Higher SpO2 (especially a minimum SpO2>97%) was unrewarding after liberal use of oxygen among patients with sICH and might even be potentially detrimental.

Bacterial contamination on clinical surfaces and oxygen device accessories in the emergency unit of a tertiary health facility in Ghana

BACKGROUND

Nosocomial infections have gradually become an emerging threat to the healthcare system over the past decades and have been attributed to poor decontamination of hospital articles and weak antibacterial stewardship policies. This study sought to investigate the effect of disinfection on the prevalence and resistance profile of bacterial contaminants on oxygen device accessories, and clinical surfaces at the emergency unit of a tertiary health facility in Ghana.

METHODS

The study employed a cross-sectional study design to evaluate the occurrence of bacteria on surfaces in a tertiary hospital. Luminal swabs of the oxygen device accessories and swabs from clinical surfaces used by healthcare providers were collected for isolation and identification of bacteria. The identified bacteria isolates were then tested for their susceptibility to antibacterial agents. Data from this study were analyzed using Excel (Microsoft Office Suite), and GraphPad Prism 8 software programs.

RESULTS

A quarter of the total 44 bacterial isolates obtained from both post-disinfected and pre-disinfected surfaces were Gram-positive, with the remaining isolates being Gram-negative. Pseudomonas aeruginosa was the most frequent bacteria species isolated (41%) followed by Citrobacter sp. (21%). P. aeruginosa, S. aureus, and S. pneumoniae were found to be highly resistant to Chloramphenicol (36%), and Sulfamethoxazole (100%); whereas Ciprofloxacin (91%) was the most effective antibacterial drug used.

CONCLUSION

The almost equal prevalence of multidrug-resistant bacteria from both post-disinfected and pre-disinfected surfaces of inanimate objects, and oxygen device accessories connote an ineffective disinfection process which may influence resistance in bacterial contaminants. This requires the overhaul of disinfection protocol and training of hospital staff, and rational use of antibacterial agents at the hospital to mitigating the burden of nosocomial infections.

Supporting patients with hypercapnia

Hypercapnia is commonly encountered by general and specialist respiratory clinicians. Patients at risk of developing hypercapnic respiratory failure include those with chronic obstructive pulmonary disease (COPD), obesity and neuromuscular disease. Such patients may present to clinicians acutely unwell on the acute medical take or during an inpatient deterioration, or be identified in the stable outpatient setting. In this review, we provide a practical guide to develop clinicians' knowledge, skills and confidence in promptly recognising and managing hypercapnic respiratory failure, and to promote national ventilation quality standards to encourage consistent delivery of high-quality care and optimise outcomes for patients.

Mycobacterium avium complex pulmonary disease patients with limited treatment options

How to identify MAC-PD patients with limited treatment options: an expert consensus https://bit.ly/3QwLQ8T.

Automated audit of hospital oxygen use devised during the COVID-19 pandemic

BACKGROUND

The British Thoracic Society (BTS) has organised intermittent audits of hospital oxygen use in UK hospitals since 2008. Manual audits are time-consuming and subject to human errors. Oxygen prescribing and bedside observations including National Early Warning Scores (NEWS2 scores) are undertaken within an integrated electronic medical record (EMR) at this hospital.

METHODS

The hospital's Business Information team were commissioned in late 2019 to devise a bespoke automated audit of oxygen prescribing and use. A summary report displays the oxygen saturation alongside the oxygen prescription status of every patient in the hospital except for critical care units which do not use NEWS2. The display has a 'traffic-light' colour scheme (green within target range, amber or red if below range or if above range on supplemental oxygen), with a graph showing oxygen use and saturation levels for patients with each prescribed target range. Clinicians can access raw data including oxygen saturation, oxygen device and flow rate for each individual patient.

RESULTS

Over 51 audits involving 34 352 sets of observations, an average of 6.0% involved use of oxygen and 88.6% of these had a valid oxygen prescription. During the first wave of the COVID-19 pandemic in spring 2020, the monthly percentage of observations involving oxygen use increased to a peak of 10.4% followed by a rise to 10.6% during the second wave and 7.4% during the third (Omicron) wave. Oxygen use returned to baseline after each wave.

CONCLUSIONS

In hospitals with integrated EMRs, it is possible to automate all fundamental aspects of the BTS oxygen audits and to monitor oxygen use at individual patient level and a hospital-wide level. This could be particularly valuable during major events such as the COVID-19 pandemic. This methodology could be extended to other clinical audits where the audit questions relate to routinely collected EMR data.

Alveolar Hyperoxia and Exacerbation of Lung Injury in Critically Ill SARS-CoV-2 Pneumonia

Acute hypoxic respiratory failure (AHRF) is a prominent feature of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) critical illness. The severity of gas exchange impairment correlates with worse prognosis, and AHRF requiring mechanical ventilation is associated with substantial mortality. Persistent impaired gas exchange leading to hypoxemia often warrants the prolonged administration of a high fraction of inspired oxygen (FiO2). In SARS-CoV-2 AHRF, systemic vasculopathy with lung microthrombosis and microangiopathy further exacerbates poor gas exchange due to alveolar inflammation and oedema. Capillary congestion with microthrombosis is a common autopsy finding in the lungs of patients who die with coronavirus disease 2019 (COVID-19)-associated acute respiratory distress syndrome. The need for a high FiO2 to normalise arterial hypoxemia and tissue hypoxia can result in alveolar hyperoxia. This in turn can lead to local alveolar oxidative stress with associated inflammation, alveolar epithelial cell apoptosis, surfactant dysfunction, pulmonary vascular abnormalities, resorption atelectasis, and impairment of innate immunity predisposing to secondary bacterial infections. While oxygen is a life-saving treatment, alveolar hyperoxia may exacerbate pre-existing lung injury. In this review, we provide a summary of oxygen toxicity mechanisms, evaluating the consequences of alveolar hyperoxia in COVID-19 and propose established and potential exploratory treatment pathways to minimise alveolar hyperoxia.

Safety and tolerability of esketamine in propofol based sedation for endoscopic variceal ligation with or without injection sclerotherapy: Randomized controlled trial

OBJECTIVES

Esketamine is an S (+) enantiomer of ketamine with greater potency and similar psychomimetic effects compared to racemic ketamine. We aimed to explore the safety of esketamine in different doses as an adjuvant to propofol in patients undergoing endoscopic variceal ligation (EVL) with or without injection sclerotherapy.

METHODS

One hundred patients were randomized to receive sedation with propofol 1.5 mg/kg in combination with sufentanil 0.1 μg/kg (group S), esketamine 0.2 mg/kg (group E0.2), esketamine 0.3 mg/kg (group E0.3), or esketamine 0.4 mg/kg (group E0.4) for EVL (n = 25 each). Hemodynamic and respiratory parameters were recorded during the procedure. The primary outcome was the incidence of hypotension; secondary outcomes included the incidence of desaturation, positive and negative syndrome scale (PANSS) after the procedure, pain score after the procedure, and secretion volume.

RESULTS

The incidence of hypotension was significantly lower in groups E0.2 (36%), E0.3 (20%), and E0.4 (24%) than in group S (72%). The incidence of SpO2  ≤94% was significantly lower in group E0.4 (4%) than in group S (32%). No significant intergroup difference was found in the PANSS assessment.

CONCLUSIONS

Combining 0.4 mg/kg esketamine with propofol sedation was optimal to facilitate EVL with stable hemodynamic status and better respiratory function during the procedure, without significant psychomimetic side-effects.

TRIAL REGISTRATION

Chinese Clinical Trial Registry (Trial ID: ChiCTR2100047033, http://www.chictr.org.cn/showproj.aspx?proj=127518).

Performance of risk scores in patients with acute exacerbations of COPD

OBJECTIVE

Acute exacerbations of COPD (AECOPD) are common causes of hospitalization. Various scoring systems have been proposed to classify the risk of clinical deterioration or mortality in hospitalized patients with AECOPD. We sought to investigate whether clinical deterioration and mortality scores at admission can predict adverse events occurring during hospitalization and after discharge of patients with AECOPD.

METHODS

We performed a retrospective study of patients admitted with AECOPD. The National Early Warning Score 2 (NEWS2), the NEWS288-92%, the Dyspnea, Eosinopenia, Consolidation, Acidemia, and atrial Fibrillation (DECAF) score, and the modified DECAF (mDECAF) score were calculated at admission. We assessed the sensitivity, specificity, and overall performance of the scores for the following outcomes: in-hospital mortality; need for invasive mechanical ventilation or noninvasive ventilation (NIV); long hospital stays; hospital readmissions; and future AECOPD.

RESULTS

We included 119 patients admitted with AECOPD. The median age was 75 years, and 87.9% were male. The NEWS288-92% was associated with an 8.9% reduction in the number of individuals classified as requiring close, continuous observation, without an increased risk of death in the group of individuals classified as being low-risk patients. The NEWS288-92% and NEWS2 scores were found to be adequate in predicting the need for acute NIV and longer hospital stays. The DECAF and mDECAF scores were found to be better at predicting in-hospital mortality than the NEWS2 and NEWS288-92%.

CONCLUSIONS

The NEWS288-92% safely reduces the need for clinical monitoring in patients with AECOPD when compared with the NEWS2. The NEWS2 and NEWS288-92% appear to be good predictors of the length of hospital stay and need for NIV, but they do not replace the DECAF and mDECAF scores as predictors of mortality.

Ten Issues for Updating in Community-Acquired Pneumonia: An Expert Review

Community-acquired pneumonia represents the third-highest cause of mortality in industrialized countries and the first due to infection. Although guidelines for the approach to this infection model are widely implemented in international health schemes, information continually emerges that generates controversy or requires updating its management. This paper reviews the most important issues in the approach to this process, such as an aetiologic update using new molecular platforms or imaging techniques, including the diagnostic stewardship in different clinical settings. It also reviews both the Intensive Care Unit admission criteria and those of clinical stability to discharge. An update in antibiotic, in oxygen, or steroidal therapy is presented. It also analyzes the management out-of-hospital in CAP requiring hospitalization, the main factors for readmission, and an approach to therapeutic failure or rescue. Finally, the main strategies for prevention and vaccination in both immunocompetent and immunocompromised hosts are reviewed.

Lower versus higher oxygen targets for out-of-hospital cardiac arrest: a systematic review and meta-analysis

BACKGROUND

Supplemental oxygen is commonly administered to patients after out-of-hospital cardiac arrest. However, the findings from studies on oxygen targeting for out-of-hospital cardiac arrest are inconclusive. Thus, we conducted a systematic review and meta-analysis to evaluate the impact of lower oxygen target compared with higher oxygen target on patients after out-of-hospital cardiac arrest.

METHODS

We searched the Cochrane Central Register of Controlled Trials, MEDLINE, Embase, from inception to February 6, 2023, for randomized controlled trials comparing lower and higher oxygen target in adults (aged ≥ 18 years) after out-of-hospital cardiac arrest. We screened studies and extracted data independently. The primary outcome was mortality at 90 days after cardiac arrest. We assessed quality of evidence using the grading of recommendations assessment, development, and evaluation approach. This study was registered with PROSPERO, number CRD42023409368.

RESULTS

The analysis included 7 randomized controlled trials with a total of 1451 participants. Compared with lower oxygen target, the use of a higher oxygen target was not associated with a higher mortality rate (relative risk 0.97, 95% confidence intervals 0.82 to 1.14; I2 = 25%). Findings were robust to trial sequential, subgroup, and sensitivity analysis.

CONCLUSION

Lower oxygen target did not reduce the mortality compared with higher oxygen target in patients after out-of-hospital cardiac arrest.