Supplemental Oxygen In Patients Research Articles

Epidemiology of supplemental oxygen in patients with pulmonary hypertension.

Patients with pulmonary hypertension (PH) may present with hypoxaemia at rest or during daily activities. There is no epidemiological data on the prescription of long-term oxygen therapy (LTOT) in patients with PH. The study sought to analyse the prevalence and incidence of LTOT prescription among patients with pulmonary arterial hypertension (PAH) or chronic thromboembolic pulmonary hypertension (CTEPH) in Spain and to determine predictors for this prescription. A retrospective analysis was performed from the Spanish Registry of Pulmonary Arterial Hypertension (REHAP). Collected data included demographics and anthropometric measurements, functional class (FC), arterial blood gases, pulmonary function tests, haemodynamic measurements, six-minute walking distance (6MWD) and LTOT prescription. In addition, we assessed the prevalence and incidence of LTOT prescription by PH group and subtype and potential predictors for LTOT initiation in the first 5 years after diagnosis. We analysed 4533 patients (69.9% PAH and 30.1% CTEPH), mostly female (64.5%), with a mean age of 53.0 ± 18.3 years. The prevalence of LTOT was 19.3% for all patients. The incidence of LTOT prescriptions decreased from 5.6% to 1.6% between 2010 and 2019, respectively. Predictors for LTOT prescription, excluding those that represent the indication for oxygen therapy were: FC (HR: 1.813), 6MWD (HR: 1.002), mean pulmonary arterial pressure (mPAP) (HR: 1.014), cardiac index (CI) (HR: 1.253), pulmonary vascular resistance (PVR) (HR: 1.023) and diffusing capacity of carbon monoxide (DLCO) (HR: 1.294). The prevalence of LTOT in PAH and CTEPH patients is close to 20%. FC, 6MWD, mPAP, CI, PVR and DLCO were predictors for LTOT prescription.

Oxygen targets following immediate percutaneous coronary intervention in comatose survivors of out-of-hospital cardiac arrest - a BOX sub-study

Abstract Funding Acknowledgements Type of funding sources: Foundation. Main funding source(s): The Novo Nordisk Foundation The Lundbeck Foundation. Background Treatment with supplemental oxygen in patients with acute myocardial infarction (AMI) has previously been associated with poorer outcomes. However, in patients with AMI resuscitated from out-of-hospital cardiac arrest (OHCA) and undergoing immediate revascularization, evidence regarding specific oxygen targets is sparse. Purpose To assess the impact of a restrictive versus a liberal oxygen target on infarct size in OHCA patients undergoing immediate percutaneous coronary intervention (PCI). Methods The current study is a sub-study of the BOX trial, a randomized trial with a 2-by-2 factorial design, in which comatose OHCA patients with a presumed cardiac cause of arrest were randomly assigned to either a restrictive oxygen target (partial pressure of arterial oxygen (Pao2) of 9 to 10 kPa) or a liberal oxygen target (Pao2 of 13 to 14 kPa). In this sub-study we included patients who underwent immediate revascularization with PCI. The primary outcome was myocardial infarct size as assessed by the cardiac enzyme troponin-T (TnT). TnT was measured repeatedly during the first 72 hours and analyzed with a repeated measures variance component model with baseline adjustment. Secondary outcome was one-year all-cause mortality assessed by Kaplan-Meier and Cox proportional hazards analyses. Results A total of 329 patients underwent immediate PCI, whereof 172 patients were randomized to the restrictive oxygen target and 157 to the liberal oxygen target. The oxygen intervention was successful with a significantly higher PaO2 in the liberal oxygen target group during the first 72 hours (p<0.0001). Baseline characteristics and findings on coronary angiography (CAG) were similar in the two oxygen target groups. Thus, median age was 63 (interquartile range (IQR) 55–71), 81% were male, and estimated left ventricular ejection fraction on arrival to hospital was 35% (IQR 25–45%). Further, 74% of the patients had an initial postresuscitation electrocardiogram with ST-segment elevations, and the left anterior descending artery was deemed as culprit lesion in 49% of the patients. There was no difference in peak TnT between the restrictive and liberal oxygen target group (median 2540 (IQR 925–6420) versus 3410 (792–8630), ng/l, p=0.23), nor did TnT differ between the groups during the first 72 hours after admission (Figure 1, p=1.00). Within one year from admission, 120 patients (36.5%) had died. There was no difference in mortality between the restrictive (34%) and liberal (39%) oxygen target group (hazard ratio, 0.80; 95% CI, 0.56-1.14; p=0.21) (Figure 2). Conclusion Targeting a restrictive versus a liberal oxygen level in comatose survivors of OHCA who underwent immediate revascularization did not affect infarct size nor did it result in a significant difference in one-year mortality rate.Figure 1:Troponin-T levelsFigure 2:Kaplan-Meier curves

Respiratory support with nasal high flow without supplemental oxygen in patients undergoing endoscopic retrograde cholangiopancreatography under moderate sedation: a prospective, randomized, single-center clinical trial

BackgroundNasal high flow (NHF) may reduce hypoxia and hypercapnia during an endoscopic retrograde cholangiopancreatography (ERCP) procedure under sedation. The authors tested a hypothesis that NHF with room air during ERCP may prevent intraoperative hypercapnia and hypoxemia.MethodsIn the prospective, open-label, single-center, clinical trial, 75 patients undergoing ERCP performed with moderate sedation were randomized to receive NHF with room air (40 to 60 L/min, n = 37) or low-flow O2 via a nasal cannula (1 to 2 L/min, n = 38) during the procedure. Transcutaneous CO2, peripheral arterial O2 saturation, a dose of administered sedative and analgesics were measured.ResultsThe primary outcome was the incidence of marked hypercapnia during an ERCP procedure under sedation observed in 1 patient (2.7%) in the NHF group and in 7 patients (18.4%) in the LFO group; statistical significance was found in the risk difference (-15.7%, 95% CI -29.1 – -2.4, p = 0.021) but not in the risk ratio (0.15, 95% CI 0.02 – 1.13, p = 0.066).In secondary outcome analysis, the mean time-weighted total PtcCO2 was 47.2 mmHg in the NHF group and 48.2 mmHg in the LFO group, with no significant difference (-0.97, 95% CI -3.35 – 1.41, p = 0.421). The duration of hypercapnia did not differ markedly between the two groups either [median (range) in the NHF group: 7 (0 – 99); median (range) in the LFO group: 14.5 (0 – 206); p = 0.313] and the occurrence of hypoxemia during an ERCP procedure under sedation was observed in 3 patients (8.1%) in the NHF group and 2 patients (5.3%) in the LFO group, with no significant difference (p = 0.674).ConclusionsRespiratory support by NHF with room air did not reduce marked hypercapnia during ERCP under sedation relative to LFO. There was no significant difference in the occurrence of hypoxemia between the groups that may indicate an improvement of gas exchanges by NHF.Trial registrationjRCTs072190021.The full date of first registration on jRCT: August 26, 2019.

Effect of Different Early Oxygenation Levels on Clinical Outcomes of Patients Presenting in the Emergency Department With Severe Traumatic Brain Injury.

Despite the almost universal administration of supplemental oxygen in patients presenting in the emergency department (ED) with severe traumatic brain injury, optimal early oxygenation levels are unknown. Therefore, we aimed to examine the effect of different early oxygenation levels on the clinical outcomes of patients presenting in the emergency department with severe traumatic brain injury. We performed a secondary analysis of the Resuscitation Outcomes Consortium Traumatic Brain Injury Hypertonic Saline randomized controlled trial by including patients with Glasgow Coma Scale ≤8. Early oxygenation levels were assessed by the worst value of arterial partial pressure of oxygen (PaO2) during the first 4 hours of presentation in the emergency department. The primary outcome was 6-month neurologic status, as assessed by the Extended Glasgow Outcome Scale. A binary logistic regression was utilized, and an odds ratio (OR) with 95% (95% confidence intervals) was calculated. A total of 910 patients were included. In unadjusted (crude) analysis, a PaO2 of 101 to 250 mmHg (OR, 0.59 [0.38 to 0.91]), or 251 to 400 mmHg (OR, 0.53 [0.34 to 0.83]) or ≥401 mmHg (OR, 0.31 [0.20 to 0.49]) was less likely to be associated with poor neurologic status when compared with a PaO2 of ≤100 mmHg. This was also the case for adjusted analyses (including age, pupillary reactivity, and Revised Trauma Score). High oxygenation levels as early as the first 4 hours of presentation in the emergency department may not be adversely associated with the long-term neurologic status of patients with severe traumatic brain injury. Therefore, during the early phase of trauma, clinicians may focus on stabilizing patients while giving low priority to the titration of oxygenation levels.

Effect of Supplemental Oxygen on von Willebrand Factor Activity and Ristocetin Cofactor Activity in Patients at Risk for Cardiovascular Complications Undergoing Moderate-to High-Risk Major Noncardiac Surgery-A Secondary Analysis of a Randomized Trial.

Increased von Willebrand Factor (vWF) activity mediates platelet adhesion and might be a contributor to the development of thrombotic complications after surgery. Although in vitro studies have shown that hyperoxia induces endovascular damage, the effect of perioperative supplemental oxygen as a possible trigger for increased vWF activity has not been investigated yet. We tested our primary hypothesis that the perioperative administration of 80% oxygen concentration increases postoperative vWF activity as compared to 30% oxygen concentration in patients at risk of cardiovascular complications undergoing major noncardiac surgery. A total of 260 patients were randomly assigned to receive 80% versus 30% oxygen throughout surgery and for two hours postoperatively. We assessed vWF activity and Ristocetin cofactor activity in all patients shortly before the induction of anesthesia, within two hours after surgery and on the first and third postoperative day. Patient characteristics were similar in both groups. We found no significant difference in vWF activity in the overall perioperative time course between both randomization groups. We observed significantly increased vWF activity in the overall study population throughout the postoperative time course. Perioperative supplemental oxygen showed no significant effect on postoperative vWF and Ristocetin cofactor activity in cardiac risk patients undergoing major noncardiac surgery. In conclusion, we found no significant influence of supplemental oxygen in patients undergoing major non-cardiac surgery on postoperative vWF activity and Ristocetin cofactor activity.

The rationale, design, and methods of a trial to evaluate the efficacy and safety of oxygen therapy in patients with intermediate-risk acute pulmonary embolism

In patients with intermediate-risk pulmonary embolism (PE), reversal of hypoxic vasoconstriction could constitute a target for treatment that protects the right ventricular (RV) function until endogenous fibrinolysis occurs. The Air vs oxygen for Intermediate-Risk pulmonary embolism (AIR) trial aims to assess the effect of oxygen therapy in patients with intermediate-risk acute PE who do not have hypoxemia at baseline. AIR is a prospective, multicenter, randomized, open-label, parallel-group, proof-of-concept trial. A total of 90 patients hospitalized with intermediate-risk PE and an oxygen saturation of 90% or higher at baseline will be randomized in a 1:1 fashion to receive supplemental oxygen or ambient air. The primary outcome is a RV/LV diameter ratio equal or less than 1.0 on echocardiography measured 48 hours after the start of treatment. Secondary efficacy outcomes are the numerical change in the ratio of the RV to the LV diameter measured 48 hours and 7 days after the start of treatment, with respect to the baseline ratio measured at randomization. Clinical adverse events will be also collected. Enrollment started in July 2019 and is expected to proceed until 2022. Median age of the first 50 patients was 74 years (interquartile range, 61-81), and 50% were female. This multicenter trial will provide information about the value of supplemental oxygen in patients with intermediate-risk acute PE who do not have hypoxemia at baseline. The results will contribute to research that may assist patients with intermediate-risk PE in the future.

RACIAL BIAS IN PULSE OXIMETRY IN ACUTE HYPOXEMIC RESPIRATORY FAILURE

RACIAL BIAS IN PULSE OXIMETRY IN ACUTE HYPOXEMIC RESPIRATORY FAILURE

Effectiveness of Regdanvimab at Preventing the Need for Oxygen Therapy in Patients with Mild-to-Moderate COVID-19: A Retrospective Cohort Study.

BackgroundMonoclonal antibodies are a treatment option for patients with mild-to-moderate coronavirus disease (COVID-19). We investigated the effectiveness of regdanvimab, an anti-severe acute respiratory syndrome coronavirus-2 monoclonal antibody approved in Korea, in the treatment of patients with mild-to-moderate COVID-19.Materials and MethodsMedical records of patients who were admitted to a COVID-19 designated hospital during the study period of February 1 to June 31 and met the indications for administration of regdanvimab were reviewed to assess baseline characteristics and clinical outcomes such as supplemental oxygen requirements, mortality, and length of hospitalization. Multivariable logistic regression analysis was conducted to identify factors associated with requiring supplemental oxygen. Subgroup analysis was performed according to the presence of pneumonia confirmed on a chest X-ray.ResultsThree hundred ninety-eight COVID-19 patients were included in the study, and 65 (16.3%) of them were administered regdanvimab. The proportion of patients requiring supplemental oxygen was significantly lower in the regdanvimab group than in the control group (6.2% vs. 20.1%, P = 0.007). There was no significant difference in mortality (0% vs. 1.5%, P >0.999) and the length of hospitalization (median: 10 days vs. 10 days, P = 0.267) between two groups. The multivariable analysis demonstrated that administration of regdanvimab was independently associated with lower oxygen supplement [odds ratio (OR): 0.20, 95% confidence interval (CI): 0.06 - 0.55, P = 0.004] after adjustment of potential risk factors related to supplemental oxygen including age, sex, chest X-ray abnormality, and underlying chronic kidney disease. Among the patients with pneumonia radiologically, administration of regdanvimab was also associated with lower risk of oxygen supplement (OR: 0.13, 95% CI: 0.02 - 0.46, P = 0.007).ConclusionRegdanvimab use was related to lower need for supplemental oxygen in patients with mild-to-moderate COVID-19 for the indications for administration of regdanvimab.

Nasal cannula or high-flow oxygen for patients with COPD in acute respiratory distress?

There may be some confusion regarding the use of supplemental oxygen in patients with chronic obstructive pulmonary disease (COPD) who are experiencing acute respiratory distress. This article addresses a common nursing misconception regarding the use of high-flow oxygen administration via non-rebreather masks instead of low-flow oxygen administration via nasal cannulas in patients with COPD who are in acute respiratory distress, an issue that was investigated in a simulation education exercise and survey of the nursing staff at the authors' facility.

The effect of oxygen inhalation on cardiac biomarkers in patients presenting with acute ST-segment elevation myocardial infraction: A randomized clinical trial.

Background: It is assumed giving oxygen to patients with acute myocardial infraction may increase the oxygenation of the ischemic tissue; however, the usefulness of oxygen in these patients has become a challenging topic. Thus, the present study aimed to determine the effect of oxygen inhalation on cardiac biomarkers in patients with acute myocardial infarction. Methods: This randomized clinical trial study was performed on 2 groups of intervention and control within 2 days of admission to critical care unit (CCU). A total of 64 patients with ST-segment elevation acute myocardial infarction who referred to Zeyaei hospital, Ardakan, were selected using simple random sampling. In the intervention group, the pulse oximetry was monitored and they only breathed regular air and received supplemental oxygen in case their oxygen level dropped below 94%. The levels of creatine kinase-MB and troponin I enzymes were measured. Data were analyzed using SPSS version 20 through repeated measure ANOVA, t test, and chi-squared test. Significance level was set at 0.05. Results: This study showed that during the 48 hours of hospitalization, there were no significant differences between the 2 groups regarding the levels of creatine kinase-MB (p=0.509) and troponin I (p=0.604). Conclusion: Since the level of cardiac biomarkers is a sign of the extent of infracted area, it is assumed receiving supplemental oxygen in patients with acute myocardial infarction has no effect on decreasing the infracted area.

Effects of hyperoxia and cardiovascular risk factors on myocardial ischaemia-reperfusion injury: a randomized, sham-controlled parallel study.

What is the central question of this study? The beneficial effects of supplemental oxygen in patients with acute myocardial infarction are still uncertain: what are the effects of ischaemia-reperfusion injury during hyperoxia and normoxia in mature rats with and without cardiovascular risk factors? What is the main finding and its importance? Despite elevated baseline oxidative stress in rodents with cardiovascular risk factors, hyperoxic reperfusion limited myocardial necrosis and anti/pro-oxidant imbalance in spontaneously hypertensive and Zucker rats. In contrast, this effect was exacerbated in healthy Wistar rats. These results suggest that oxygen supplementation may not be harmful in patients with acute myocardial injury. Recent studies on O2 supplementation in acute coronary syndrome patients are equivocal. We tested the hypothesis that oxidative stress is increased in rodents with cardiovascular risk factors and enhances ischaemia-reperfusion injury in the presence of hyperoxia. A total of 43 Wistar rats (WR), 30 spontaneously hypertensive rats (SHR) and 33 obese Zucker rats (ZR) were randomized in a sham procedure (one-third) or underwent a left anterior descending ligation of the coronary artery for 60min (two-thirds). This was followed by 3h of reperfusion while animals were randomized either in a hyperoxic (HR) or a normoxic reperfusion (NR) group. Myocardial infarction size and oxidative stress biomarkers (myeloperoxidase (MPO), malondialdehyde and total free thiols) were assessed in blood samples. Baseline troponin T was higher in SHR and ZR than in WR (both P<0.001). Baseline total MPO was elevated in ZR in comparison to SHR and WR (both P<0.001). SHR had lower thiol concentration compared to WR and ZR (P<0.000001). HR was associated with a lower troponin T rise in SHR and ZR than in NR (both P<0.001), while the reverse occurred in WR (P<0.001). In SHR, HR limited total MPO increase as compared to NR (P=0.0056) and the opposite effect was observed with total MPO in WR (P=0.013). NR was associated with a drastic reduction of total thiols as compared to HR both in SHR and in ZR (both P<0.001). Despite a heightened baseline oxidative stress level, HR limited myocardial necrosis and anti/pro-oxidant imbalance in SHR and ZR whereas this effect was exacerbated in healthy WR.

Supplemental Oxygen for Patients with Chronic Obstructive Pulmonary Disease and Isolated Nocturnal Desaturations

Trials in the early 1980s established the mortality benefit of nocturnal oxygen to treat patients with chronic obstructive pulmonary disease (COPD) and

Efficacy of high-flow nasal prong therapy in trauma patients with rib fractures and high-risk features for respiratory deterioration: a randomized controlled trial

BackgroundPatients with rib fractures require analgesia, oxygen supplementation and physiotherapy. This combination has been shown to reduce morbidity and mortality due to rib fractures. There has been movement towards the...

Obstructive sleep apnea and pulmonary hypertension: a bidirectional relationship.

Citation:Mesarwi O, Malhotra A. Obstructive sleep apnea and pulmonary hypertension: a bidirectional relationship. J Clin Sleep Med. 2020;16(8):1223–1224.

Effect of Oxygen Therapy on Cardiovascular Outcomes in Relation to Baseline Oxygen Saturation

ObjectivesThe aim of this study was to determine the effect of supplemental oxygen in patients with myocardial infarction (MI) on the composite of all-cause death, rehospitalization with MI, or heart failure related to baseline oxygen saturation. A secondary objective was to investigate outcomes in patients developing hypoxemia. BackgroundIn the DETO2X-AMI (Determination of the Role of Oxygen in Suspected Acute Myocardial Infarction) trial, 6,629 normoxemic patients with suspected MI were randomized to oxygen at 6 l/min for 6 to 12 h or ambient air. MethodsThe study population of 5,010 patients with confirmed MI was divided by baseline oxygen saturation into a low-normal (90% to 94%) and a high-normal (95% to 100%) cohort. Outcomes are reported within 1 year. To increase power, all follow-up time (between 1 and 4 years) was included post hoc, and interaction analyses were performed with oxygen saturation as a continuous covariate. ResultsThe composite endpoint of all-cause death, rehospitalization with MI, or heart failure occurred significantly more often in patients in the low-normal cohort (17.3%) compared with those in the high-normal cohort (9.5%) (p < 0.001), and most often in patients developing hypoxemia (23.6%). Oxygen therapy compared with ambient air was not associated with improved outcomes regardless of baseline oxygen saturation (interaction p values: composite endpoint, p = 0.79; all-cause death, p = 0.33; rehospitalization with MI, p = 0.86; hospitalization for heart failure, p = 0.35). ConclusionsIrrespective of oxygen saturation at baseline, we found no clinically relevant beneficial effect of routine oxygen therapy in normoxemic patients with MI regarding cardiovascular outcomes. Low-normal baseline oxygen saturation or development of hypoxemia was identified as an independent marker of poor prognosis. (An Efficacy and Outcome Study of Supplemental Oxygen Treatment in Patients With Suspected Myocardial Infarction; NCT01787110)

Oxygen Administration Does Not Influence the Prognosis of Acute Myocardial Infarction: A Meta-Analysis.

The safety and efficacy of supplemental oxygen in acute myocardial infarction (AMI) remains unclear. To evaluate the safety and efficacy of supplemental oxygen in patients who present with AMI. We systematically searched PubMed, Embase, Cochrane Central Register of Controlled Trials, ISI Web of Science, Scopus, and conference proceedings from inception through January 2016. Eligible studies were randomized trials that evaluated the role of oxygen compared with room air in AMI. The clinical outcome measured was 30-day mortality, and odds ratio (OR) was calculated for the measured outcome. The Mantel-Haenszel method was used to pool 30-day mortality in a random-effects model. Sensitivity analysis was carried out to evaluate the effect of revascularization of the culprit artery on the outcome. The pooled analysis suggested no difference in 30-day mortality [OR 1.09; 95% confidence interval (CI), 0.30-4.00; P = 0.89] between oxygen and room air. Metaregression demonstrated that all the between-study variance was because of coronary revascularization (P = 0.01, R = 1.0). A subgroup analysis suggested a trend toward increased mortality with oxygen (OR 3.26; 95% CI, 0.94-11.29; P = 0.06) when less than half of the patient population underwent revascularization. On the other hand, there was a nonsignificant numerical decrease in mortality with oxygen (OR 0.41; 95% CI, 0.14-1.19; P = 0.10) in the presence of coronary revascularization. Metaregression confirmed that all the between-study variance was because of coronary revascularization (P = 0.01, R = 1.0). In this meta-analysis, we found that the evidence on the safety and efficacy of oxygen was not only weak and inconsistent but also had modest statistical power. The variation in results was mainly because of the presence or absence of revascularization of the culprit artery. Adequately powered studies are needed to further delineate the role of oxygen in patients undergoing coronary revascularization.

ROUTINE USE OF SUPPLEMENTAL OXYGEN IN PATIENTS WITH MYOCARDIAL INFARCTION WITHOUT HYPOXIA IS ASSOCIATED WITH HIGHER RATES OF RE-INFARCTION: A META-ANALYSIS

SESSION TITLE: Cardiovascular Disease SESSION TYPE: Original Investigation Posters PRESENTED ON: 10/10/2018 01:00 PM - 02:00 PM PURPOSE: Routine use of oxygen in patients with myocardial infarction (MI) used to be the standard of practice until recently. However, recent studies have not shown any benefits in this setting. In addition, recently published AVOID study showed that routine use of oxygen is associated with a larger 6-month myocardial infarct size. At the same time, several studies published recently failed to show any harmful effect of the routine use of oxygen. We did this meta-analysis to further explore this controversial issue. We are aiming to assess whether routine use of oxygen is associated with worsened clinical outcomes. METHODS: We used the PRISMA model for our analysis. We performed a systematic search of PubMed, Scopus, Cochrane library and clinicaltrial.gov since inception till January 2017. We used following terms for the search: “infarction”, “myocardial infarction”, “acute coronary syndrome”, “ACS”, “MI”, “oxygen therapy”, “oxygen effect”, “oxygen supplementation” and “oxygen treatment”. Total of 5 studies was included in our analysis. We used RevMan 5.3 for windows (Cochrane Collaboration, Oxford, United Kingdom) for all the analysis. We used random effect model for analysis of the continuous and dichotomous variables. We used Mental-Haenszel method for the analysis. In addition, we used a confidence interval of 95% as significant and along with p-value of less than 0.5 as significant. Heterogeneity was measured using I2. The heterogeneity of <30 % was considered low, 30%-60 % was considered moderate and >60% was considered substantial. We calculated the mean difference (MD) and odds ratio (OR) for the continuous and dichotomous variables respectively RESULTS: A total of 914 patients were included in our analysis (449 in oxygen group). Infarcted myocardial mass between two groups was not significantly different (MD, 2.76-gram, 95% CI [-1.94, 7.47], a p-value 0.25; I2=67%). Similarly, we did not find a significant difference in percent infarct mass (MD, 1.48 %, CI [-1.34, 4.29], p-value 0.30; I2= 55%). We did not find any significant difference in EF between two groups (MD, -0.71, 95% CI [-3.94, 2.53], a p-value 0.67; I2= 0%). However, we found a significant increase in the incidence of re-infarction in oxygen group(4.92% vs 0.73%) (OR, 5.70, 95%, CI [1.45, 22.35], p-value 0.01; I2= 0%). There was no significant difference between two groups in in-hospital mortality (OR,1.06, 95% CI [0.30, 3.70], p-value 0.93;I2= 49%). CONCLUSIONS: Regular use of supplemental oxygen in MI without hypoxia is associated with adverse clinical outcome secondary to increased rates of re-infarction. CLINICAL IMPLICATIONS: There is uncertainty regarding the use of supplemental oxygen in patients with MI without heart failure or dyspnea in the recent guidelines. In light of our evidence of increased adverse clinical outcome, we think the guidelines should actually now recommend against the regular supplemental use of oxygen. DISCLOSURES: No relevant relationships by Ghassan Bachuwa, source=Web Response No relevant relationships by Sai Pavan Kumar Chintalapati, source=Web Response No relevant relationships by Sunil Upadhaya, source=Web Response No relevant relationships by Ravi Kanth Velagapudi, source=Web Response

The Analgesic Effect of Oxygen in Suspected Acute Myocardial Infarction: A Substudy of the DETO2X-AMI Trial

ObjectivesIn this substudy of the DETO2X-AMI (An Efficacy and Outcome Study of Supplemental Oxygen Treatment in Patients With Suspected Myocardial Infarction) trial, the authors aimed to assess the analgesic effect of moderate-flow oxygen supplementation in patients with suspected acute myocardial infarction (AMI) treated with percutaneous coronary intervention (PCI) and to study the effect of oxygen supplementation on the use of opiates and sedatives during PCI. BackgroundRoutine oxygen in normoxemic patients with AMI does not provide clinical benefit. However, oxygen may relieve ischemic pain. MethodsPatients were randomly allocated to oxygen or ambient air according to the main study protocol. After PCI, peak level of pain during PCI was measured by the Visual Analogue Scale. The total amount of opiates and sedatives was reported. ResultsA total of 622 patients were enrolled: 330 in the oxygen group and 292 in the ambient air group. There was no significant difference in peak level of pain (oxygen 4.0 [1.0 to 6.0] vs. air 3.0 [0.6 to 6.0]; p = 0.37), use of opiates (mg) (oxygen 0.0 [0.0 to 3.0] vs. air 0.0 [0.0 to 3.0]; p = 0.31), or use of sedatives between the groups (median [interquartile range]) (oxygen 2.5 [0.0 to 2.5] vs. air 2.5 [0.0 to 2.5]; p = 0.74). ConclusionsIn the present study, the authors did not find any analgesic effect of routine oxygen as compared with ambient air, and no differences in the use of sedatives and opiates during PCI. Our results indicate that moderate-flow oxygen supplementation does not relieve pain in normoxemic patients with suspected AMI undergoing treatment with PCI and should thus not be used for this purpose.

Oxygen therapy in ST-elevation myocardial infarction.

To determine whether supplemental oxygen in patients with ST-elevation myocardial infarction (STEMI) impacts on procedure-related and clinical outcomes. The DETermination of the role of Oxygen in suspected Acute Myocardial Infarction (DETO2X-AMI) trial randomized patients with suspected myocardial infarction (MI) to receive oxygen at 6 L/min for 6-12 h or ambient air. In this pre-specified analysis, we included only STEMI patients who underwent percutaneous coronary intervention (PCI). In total, 2807 patients were included, 1361 assigned to receive oxygen, and 1446 assigned to ambient air. The pre-specified primary composite endpoint of all-cause death, rehospitalization with MI, cardiogenic shock, or stent thrombosis at 1 year occurred in 6.3% (86 of 1361) of patients allocated to oxygen compared to 7.5% (108 of 1446) allocated to ambient air [hazard ratio (HR) 0.85, 95% confidence interval (95% CI) 0.64-1.13; P = 0.27]. There was no difference in the rate of death from any cause (HR 0.86, 95% CI 0.61-1.22; P = 0.41), rate of rehospitalization for MI (HR 0.92, 95% CI 0.57-1.48; P = 0.73), rehospitalization for cardiogenic shock (HR 1.05, 95% CI 0.21-5.22; P = 0.95), or stent thrombosis (HR 1.27, 95% CI 0.46-3.51; P = 0.64). The primary composite endpoint was consistent across all subgroups, as well as at different time points, such as during hospital stay, at 30 days and the total duration of follow-up up to 1356 days. Routine use of supplemental oxygen in normoxemic patients with STEMI undergoing primary PCI did not significantly affect 1-year all-cause death, rehospitalization with MI, cardiogenic shock, or stent thrombosis.

Adherence to long-term oxygen therapy in patients with chronic obstructive pulmonary disease.

Long-term oxygen therapy (LTOT) has beneficial effects on survival in patients with chronic obstructive pulmonary disease (COPD) and severe hypoxemia at rest. Two landmark trials suggested that these benefits depend on the time of exposure to oxygen. Patients are usually prescribed LTOT for at least 15–18 hours/day. The primary objective of this study was to determine the average daily exposure to supplemental oxygen in patients with severely hypoxemic COPD who were newly prescribed LTOT and the proportion of patients who were adherent to their prescription. The secondary objective was to identify predictors of compliance to LTOT. We performed a retrospective observational study of patients newly registered in a regional home oxygen program in Quebec, Canada, between July 1, 2013, and December 31, 2014. Daily exposure to oxygen was objectively measured from the concentrator’s counter clock. From 196 patients registered in the program during the study period, 115 contributed to the analysis. Most patients (n = 84; 73%) were prescribed oxygen for ≥18 hours/day. Overall, the 115 patients were exposed to home oxygen for 17.8 hours/day; 60% of the patients were compliant according to our definition. Increasing age and ambulatory oxygen utilization predicted adherence to oxygen therapy. Adherence to home oxygen therapy is suboptimal. Behavioral and psychological interventions to improve compliance to LTOT should be investigated.