The association of arterial partial oxygen pressure with mortality in critically ill sepsis patients: a nationwide observational cohort study.

BACKGROUND: Although several trials were conducted to optimize the oxygenation range in intensive care unit (ICU) patients, no studies have yet reached a universal recommendation on the optimal a partial pressure of oxygen in arterial blood (PaO2) range in patients with sepsis. Our aim was to evaluate whether a relatively high arterial oxygen tension is associated with longer survival in sepsis patients compared with conservative arterial oxygen tension. METHODS: From the Korean Sepsis Alliance nationwide registry, patients treated with liberal PaO2 (PaO2 ≥ 80 mm Hg) were 1:1 matched with those treated with conservative PaO2 (PaO2 < 80 mm Hg) over the first three days after ICU admission according to the propensity score. The primary outcome was 28-day mortality. RESULTS: The median values of PaO2 over the first three ICU days in 1211 liberal and 1211 conservative PaO2 groups were, respectively, 107.2 (92.0-134.0) and 84.4 (71.2-112.0) in day 1110.0 (93.4-132.0) and 80.0 (71.0-100.0) in day 2, and 106.0 (91.9-127.4) and 78.0 (69.0-94.5) in day 3 (all p-values < 0.001). The liberal PaO2 group showed a lower likelihood of death at day 28 (14.9%; hazard ratio [HR], 0.79; 95% confidence interval [CI] 0.65-0.96; p-value = 0.017). ICU (HR, 0.80; 95% CI 0.67-0.96; p-value = 0.019) and hospital mortalities (HR, 0.84; 95% CI 0.73-0.97; p-value = 0.020) were lower in the liberal PaO2 group. On ICU days 2 (p-value = 0.007) and 3 (p-value < 0.001), but not ICU day 1, hyperoxia was associated with better prognosis compared with conservative oxygenation., with the lowest 28-day mortality, especially at PaO2 of around 100 mm Hg. CONCLUSIONS: In critically ill patients with sepsis, higher PaO2 (≥ 80 mm Hg) during the first three ICU days was associated with a lower 28-day mortality compared with conservative PaO2.

Outcomes After Extracorporeal Life Support Cannulation in Pediatric Patients With Trisomy 13 and Trisomy 18.

BACKGROUND: Indications for extracorporeal life support (ECLS) have evolved and expanded, yet its use in trisomy 13 (T13) and trisomy 18 (T18) patients remains controversial. We reviewed the experience of the Extracorporeal Life Support Organization with ECLS in these patients to inform practice at our institution. METHODS: The Extracorporeal Life Support Organization registry was queried for all patients younger than 18 y with an International Classification of Diseases, Ninth Edition/Tenth Edition code for T13 or T18 from 2000 to 2018. Basic demographics, ECLS details, and clinical outcomes were recorded. Descriptive statistics were performed. RESULTS: Twenty-eight patients were identified (15 with T13; 13 with T18), representing 0.06% (28 of 46,901) of pediatric ECLS cannulations. The median weight was 3.5 kg (range, 1.4-13), and age at cannulation was 52 d (range, 0 d-6.8 y). Time on ECLS ranged from 13 to 478 h (median, 114). Cardiac defects were diagnosed in 19 (68%) patients, of which 13 (46%) underwent surgical repair. Median oxygenation index pre-ECLS was 45. Venoarterial cannulations accounted for 82% of patients, whereas 14% underwent venovenous cannulation. Overall survival to hospital discharge was 46% with 86% of patients experiencing one or more complications. There were no survivors when cannulation continued past 12 d. CONCLUSIONS: Although complications are frequent, the mortality rate in patients with T13 and T18 remains within the reported range for the general pediatric population. T13 and T18 alone should not be viewed as absolute contraindications to ECLS within the pediatric population but rather considered during the evaluation of a patient's potential candidacy.

Prognostic value of central venous-to-arterial carbon dioxide difference in patients with bloodstream infection.

Background: Bloodstream infection (BSI) are prone to circulation disorders, which portend poor outcome. The central venous-to-arterial carbon dioxide difference (Pcv-aCO2) is a biomarker for circulation disorders, but the prognostic value of Pcv-aCO2 in BSI patients remains unclear. This study was to investigate the association of Pcv-aCO2 with adverse events in BSI patients. Methods: The patients with BSI between August 2014 and August 2017 were prospectively enrolled. Clinical characteristic and laboratory results were collected. We analyzed the association of the level of Pcv-aCO2 with clinical variables and 28-day mortality. Results: A total of 152 patients were enrolled. The Pcv-aCO2 was positively correlated with white blood cell count (r=0.241, p=0.003), procalcitonin (r=0.471, p<0.001), C-reactive protein (r=0.192, p=0.018), lactate (r=0.179, p=0.027), Sequential Organ Failure Assessment (r=0.318, p<0.001) and Acute Physiology And Chronic Health Evaluation II score (r=0.377, p<0.001), while that was negatively correlated with central venous oxygen saturation (r=-0.242, p<0.001) and platelet (r=-0.205, p=0.011). Kaplan-Meier curves demonstrated that patients with Pcv-aCO2 >6mmHg had a worse prognosis than those without (log rank=32.10, p<0.001). Multivariate analysis showed Level of Pcv-aCO2 was an independent risk factor for 28-day mortality (HR: 3.10, 95% CI: 1.43-6.74, p=0.004). The area under the receiver operating characteristic curve of Pcv-aCO2 for prediction of 28-day mortality in patients with BSI was 0.794. Pcv-aCO2>6 mmHg had 81.1% sensitivity and 78.8% specificity for predicting 28-day mortality. Conclusion: Pcv-aCO2 may be a simple and valuable biomarker to assessment of 28-day mortality in patients with BSI.

Predictive value of capnography for severity of acute gastroenteritis in the emergency department.

OBJECTIVE: This study first aims to assess the utility of ETCO2 levels in evaluating the severity of dehydration in adult patients that present to the ED with acute gastroenteritis. AGE. Second, it intends to evaluate the correlation between ETCO2 and several metabolic parameters: creatinine, pH, bicarbonate (HCO3), and bases excessive (BE). METHOD: This prospective study was conducted with AGE patients in the ED of a training and research hospital between June 2018 and April 2019 after approval of the local ethical-committee. The two groups were defined according to the severity of AGE: mild and non-mild groups. For both groups, ETCO2 levels were measured and recorded on admission of the patients. RESULTS: 87 patients were included in the analyses. The median of ETCO2 values was found as lower in non-mild group than mild group; 30 (25-35) & 39 (33-34), respectively (p < 0.001). In ROC analysis for distinguishing between the both groups, the AUC value was found to be 0.988 and the best cut-off level was found as 33.5 with 95% sensitivity and 93% specificity. In addition, strong negative correlation between ETCO2 and creatinine (p < 0.001, r: -0.771) were found. CONCLUSION: ETCO2 levels decreased in the non-mild group of AGE patients; it could be useful to distinguish the mild group from the non-mild group. ETCO2 could be a reliable marker in predicting AKI in the management of AGE patients.

Relationship Between Partial Carbon Dioxide Pressure and Strong Ions in Humans: A Retrospective Study.

Little is known about the role of a strong ions in humans with respiratory abnormalities. In this study, we investigated the associations between partial carbon dioxide pressure (pCO2) and each of sodium ion (Na+) concentrations, chloride ion (Cl-) concentrations and their difference (SIDNa-Cl). Blood gas data were obtained from patients in a teaching hospital intensive care unit between August 2013 and January 2017. The association between pCO2 and SIDNa-Cl was defined as the primary outcome. The associations between pCO2 and [Cl-], [Na+] and other strong ions were secondary outcomes. pCO2 was stratified into 10 mmHg-wide bands and treated as a categorical variable for comparison. As a result, we reviewed 115,936 blood gas data points from 3,840 different ICU stays. There were significant differences in SIDNa-Cl, [Cl-], and [Na+] among all categorized pCO2 bands. The respective pCO2 SIDNa-Cl, [Cl-], and [Na+] correlation coefficients were 0.48, -0.31, and 0.08. SIDNa-Cl increased and [Cl-] decreased with pCO2, with little relationship between pCO2 and [Na+] across subsets. In conclusion, we found relatively strong correlations between pCO2 and SIDNa-Cl in the multiple blood gas datasets examined. Correlations between pCO2 and chloride concentrations, but not sodium concentrations, were further found to be moderate in these ICU data.

Early nasal high-flow versus Venturi mask oxygen therapy after lung resection: a randomized trial.

BACKGROUND: Data on high-flow nasal oxygen after thoracic surgery are limited and confined to the comparison with low-flow oxygen. Different from low-flow oxygen, Venturi masks provide higher gas flow at a predetermined fraction of inspired oxygen (FiO2). We conducted a randomized trial to determine whether preemptive high-flow nasal oxygen reduces the incidence of postoperative hypoxemia after lung resection, as compared to Venturi mask oxygen therapy. METHODS: In this single-center, randomized trial conducted in a teaching hospital in Italy, consecutive adult patients undergoing thoracotomic lung resection, who were not on long-term oxygen therapy, were randomly assigned to receive high-flow nasal or Venturi mask oxygen after extubation continuously for two postoperative days. The primary outcome was the incidence of postoperative hypoxemia (i.e., ratio of the partial pressure of arterial oxygen to FiO2 (PaO2/FiO2) lower than 300 mmHg) within four postoperative days. RESULTS: Between September 2015 and April 2018, 96 patients were enrolled; 95 patients were analyzed (47 in high-flow group and 48 in Venturi mask group). In both groups, 38 patients (81% in the high-flow group and 79% in the Venturi mask group) developed postoperative hypoxemia, with an unadjusted odds ratio (OR) for the high-flow group of 1.11 [95% confidence interval (CI) 0.41-3] (p = 0.84). No inter-group differences were found in the degree of dyspnea nor in the proportion of patients needing oxygen therapy after treatment discontinuation (OR 1.34 [95% CI 0.60-3]), experiencing pulmonary complications (OR 1.29 [95% CI 0.51-3.25]) or requiring ventilatory support (OR 0.67 [95% CI 0.11-4.18]). Post hoc analyses revealed that PaO2/FiO2 during the study was not different between groups (p = 0.92), but patients receiving high-flow nasal oxygen had lower arterial pressure of carbon dioxide, with a mean inter-group difference of 2 mmHg [95% CI 0.5-3.4] (p = 0.009), and were burdened by a lower risk of postoperative hypercapnia (adjusted OR 0.18 [95% CI 0.06-0.54], p = 0.002). CONCLUSIONS: When compared to Venturi mask after thoracotomic lung resection, preemptive high-flow nasal oxygen did not reduce the incidence of postoperative hypoxemia nor improved other analyzed outcomes. Further adequately powered investigations in this setting are warranted to establish whether high-flow nasal oxygen may yield clinical benefit on carbon dioxide clearance. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02544477 . Registered 9 September 2015.

Correlation between sodium, potassium, hemoglobin, hematocrit, and glucose values as measured by a laboratory autoanalyzer and a blood gas analyzer.

INTRODUCTION: Blood gas analyzers can be alternatives to laboratory autoanalyzers for obtaining test results in just a few minutes. We aimed to find out whether the results from blood gas analyzers are reliable when compared to results of core laboratory autoanalyzers. MATERIALS AND METHODS: This retrospective, single-centered study examined the electronic records of patients admitted to the emergency department of a tertiary care teaching hospital between May 2014 and December 2017. Excluded from the study were patients under 18 years old, those lacking data, those who had any treatment before the laboratory tests, those whose venous gas results were reported more than 30 minutes after the blood sample was taken and for whom any of the laboratory tests were performed at a different time, and recurrent laboratory results from a single patient. RESULTS: Laboratory results were analyzed from a total of 31,060 patients. The correlation coefficients for sodium, potassium, hemoglobin, hematocrit, and glucose levels measured by a blood gas analyzer and a laboratory autoanalyzer were 0.725, 0.593, 0.982, 0.958, and 0.984, respectively; however, there were no good, acceptable agreement limits for any of the parameters. In addition, these results did not change according to the different pH stages (acidosis, normal pH and alkalosis). CONCLUSION: The two types of measurements showed a moderate correlation for sodium and potassium levels and a strong correlation for glucose, hemoglobin, and hematocrit levels, but none of the levels had acceptable agreement limits. Clinicians should be aware of the limitations of blood gas analyzer results.

Admission Hyperoxia Is a Risk Factor for Mortality in Pediatric Intensive Care.

OBJECTIVES: To determine whether the association between hyperoxia and increased risk-adjusted mortality in adult intensive care patients is also observed in a pediatric intensive care population. DESIGN: Single-center retrospective analysis of admissions to ICU over a 5-year period commencing January 1, 2012, examining the relationship between PaO2 measured within the first hour of admission and risk-adjusted mortality. Standardized mortality rates were calculated using the Pediatric Index of Mortality-3, and patients were grouped into 50 mm Hg (6.67 kPa) PaO2 bands to assess the relationship between initial PaO2 and risk-adjusted mortality. SETTING: Tertiary PICU with 17 beds and 1,100 annual admissions located in metropolitan Sydney, Australia. PATIENTS: A total of 1,447 patients 0-18 years old with PaO2 recorded at admission to the ICU. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: There were 5,176 patients admitted to the ICU during the study period and 1,447 (28%) with PaO2 recorded at admission. A U-shaped relationship between raw mortality and admission PaO2 was observed, with lowest mortality (2.3% and 2.6%, respectively) observed in the 101-150 (13.5-20.0 kPa) and 151-200 mm Hg (20.1-26.7 kPa) bands and the highest mortality observed in patients with PaO2 less than 50 mm Hg (6.67 kPa) with mortality of 5.3%, or greater than 350 mm Hg (46.7 kPa) with mortality of 18.2%. Hyperoxia at admission was associated with an increase in risk-adjusted mortality, with polynomial regression indicating a strong correlation between PaO2 band and risk-adjusted outcome (r = 0.845). When included in a multivariate model that included the Pediatric Index of Mortality-3 variables, the odds ratio for hyperoxia (defined as PaO2 > 250 mm Hg [33.3 kPa]) predicting death was 2.66 (p = 0.047). CONCLUSIONS: In this single-center study, hyperoxia at admission to the PICU was highly correlated with increased risk-adjusted mortality. Further investigation of these observations in a large multicenter cohort is warranted.

Should the 6-Minute Walk Test Be Stopped If Oxyhemoglobin Saturation Falls Below 80%?

OBJECTIVE: To examine the occurrence of adverse events in patients undergoing assessment for pulmonary rehabilitation when a 6-minute walk test (6MWT) continues despite desaturation below 80%. DESIGN: Retrospective audit following REporting of studies Conducted using Observational Routinely-collected health Data (RECORD) Statement. SETTING: Large teaching hospital. PARTICIPANTS: All patients (N=549) (55% men, mean age 69±11y) assessed for pulmonary rehabilitation (September 2005 to January 2016). INTERVENTIONS: The standardized tests were conducted by experienced cardiorespiratory physiotherapists. Oxyhemoglobin saturation was monitored continuously using a pulse oximeter (lowest value used for analysis). Medical records were reviewed, and adverse events defined as tachycardia, bradycardia, chest pain, or other sign/symptom necessitating cessation. MAIN OUTCOME MEASURE: 6MWT. RESULTS: Data from 672 walk tests were included with mean distance 369 (124) meters. The main diagnoses were chronic obstructive pulmonary disease (70%), interstitial lung disease (14%), and bronchiectasis (8%). Sixty individuals (11%) recorded desaturation below 80% without adverse events. Two adverse events were recorded during tests without desaturation; in 1 instance, chest pain with no evidence of cardiorespiratory compromise and in another, the patient stopped due to concern regarding blood sugar levels (11.5 mmol/L when tested). Independent predictors of desaturation to less than 80% were resting oxyhemoglobin saturation <95% (odds ratio [OR] 3.82, 95% confidence interval [CI] 2.06-7.08) and a diagnosis of interstitial lung disease or pulmonary arterial hypertension (OR 5.24, 95% CI 2.59-10.58). CONCLUSIONS: This study found that desaturation to less than 80% during a 6MWT was not associated with adverse events in a large cohort of patients referred to pulmonary rehabilitation and assessed by experienced physiotherapists, suggesting that test cessation due to desaturation in stable patients may be unwarranted.

A Multicenter Randomized Trial Assessing the Efficacy of Helium/Oxygen in Severe Exacerbations of Chronic Obstructive Pulmonary Disease.

RATIONALE: During noninvasive ventilation (NIV) for chronic obstructive pulmonary disease (COPD) exacerbations, helium/oxygen (heliox) reduces the work of breathing and hypercapnia more than air/O2, but its impact on clinical outcomes remains unknown. OBJECTIVES: To determine whether continuous administration of heliox for 72 hours, during and in-between NIV sessions, was superior to air/O2 in reducing NIV failure (25-15%) in severe hypercapnic COPD exacerbations. METHODS: This was a prospective, randomized, open-label trial in 16 intensive care units (ICUs) and 6 countries. Inclusion criteria were COPD exacerbations with PaCO2 ≥ 45 mm Hg, pH ≤ 7.35, and at least one of the following: respiratory rate ≥ 25/min, PaO2 ≤ 50 mm Hg, and oxygen saturation (arterial [SaO2] or measured by pulse oximetry [SpO2]) ≤ 90%. A 6-month follow-up was performed. MEASUREMENTS AND MAIN RESULTS: The primary endpoint was NIV failure (intubation or death without intubation in the ICU). The secondary endpoints were physiological parameters, duration of ventilation, duration of ICU and hospital stay, 6-month recurrence, and rehospitalization rates. The trial was stopped prematurely (445 randomized patients) because of a low global failure rate (NIV failure: air/O2 14.5% [n = 32]; heliox 14.7% [n = 33]; P = 0.97, and time to NIV failure: heliox group 93 hours [n = 33], air/O2 group 52 hours [n = 32]; P = 0.12). Respiratory rate, pH, PaCO2, and encephalopathy score improved significantly faster with heliox. ICU stay was comparable between the groups. In patients intubated after NIV failed, patients on heliox had a shorter ventilation duration (7.4 ± 7.6 d vs. 13.6 ± 12.6 d; P = 0.02) and a shorter ICU stay (15.8 ± 10.9 d vs. 26.7 ± 21.0 d; P = 0.01). No difference was observed in ICU and 6-month mortality. CONCLUSIONS: Heliox improves respiratory acidosis, encephalopathy, and the respiratory rate more quickly than air/O2 but does not prevent NIV failure. Overall, the rate of NIV failure was low. Clinical trial registered with www.clinicaltrials.gov (NCT 01155310).

Respiratory quotient estimations as additional prognostic tools in early septic shock.

Central venous-to-arterial carbon dioxide difference (PcvaCO2), and its correction by the arterial-to-venous oxygen content difference (PcvaCO2/CavO2) have been proposed as additional tools to evaluate tissue hypoxia. Since the relationship between pressure and content of CO2 (CCO2) might be affected by several factors, some authors advocate for the use of CcvaCO2/CavO2. The aim of the present study was to explore the factors that might intervene in the difference between PcvaCO2/CavO2 and CcvaCO2/CavO2, and to analyze their association with mortality. Observational study in a 30-bed mixed ICU. Fifty-two septic shock patients within the first 24 h of ICU admission were studied. After restoration of mean arterial pressure, hemodynamic and metabolic parameters were evaluated. A total of 110 sets of measurements were performed. Simultaneous PcvaCO2/CavO2 and CcvaCO2/CavO2 values were correlated, but agreement analysis showed a significant proportional bias. The difference between PcvaCO2/CavO2 and CcvaCO2/CavO2 was independently associated with pH, ScvO2, baseline CcvaCO2/CavO2 and hemoglobin. A stepwise regression analysis showed that pH was the single best predictor for the magnitude of such difference, with very limited effect of other variables. At inclusion, variables associated with ICU-mortality were lactate, pH, PcvaCO2/CavO2, and the difference between PcvaCO2/CavO2 and CcvaCO2/CavO2. Initial ScvO2, PcvaCO2, CcvaCO2/CavO2, and cardiac index were not different in survivors and non-survivors. In a population of early septic shock patients, simultaneous values of PcvaCO2/CavO2 and CcvaCO2/CavO2 were not equivalent, and the main determinant of the magnitude of the difference between these two parameters was pH. The PcvaCO2/CavO2 ratio was associated with ICU mortality, whereas CcvaCO2/CavO2 was not.

A pilot clinical trial of recombinant human angiotensin-converting enzyme 2 in acute respiratory distress syndrome.

BACKGROUND: Renin-angiotensin system (RAS) signaling and angiotensin-converting enzyme 2 (ACE2) have been implicated in the pathogenesis of acute respiratory distress syndrome (ARDS). We postulated that repleting ACE2 using GSK2586881, a recombinant form of human angiotensin-converting enzyme 2 (rhACE2), could attenuate acute lung injury. METHODS: We conducted a two-part phase II trial comprising an open-label intrapatient dose escalation and a randomized, double-blind, placebo-controlled phase in ten intensive care units in North America. Patients were between the ages of 18 and 80 years, had an American-European Consensus Criteria consensus diagnosis of ARDS, and had been mechanically ventilated for less than 72 h. In part A, open-label GSK2586881 was administered at doses from 0.1 mg/kg to 0.8 mg/kg to assess safety, pharmacokinetics, and pharmacodynamics. Following review of data from part A, a randomized, double-blind, placebo-controlled investigation of twice-daily doses of GSK2586881 (0.4 mg/kg) for 3 days was conducted (part B). Biomarkers, physiological assessments, and clinical endpoints were collected over the dosing period and during follow-up. RESULTS: Dose escalation in part A was well-tolerated without clinically significant hemodynamic changes. Part B was terminated after 39 of the planned 60 patients following a planned futility analysis. Angiotensin II levels decreased rapidly following infusion of GSK2586881, whereas angiotensin-(1-7) and angiotensin-(1-5) levels increased and remained elevated for 48 h. Surfactant protein D concentrations were increased, whereas there was a trend for a decrease in interleukin-6 concentrations in rhACE2-treated subjects compared with placebo. No significant differences were noted in ratio of partial pressure of arterial oxygen to fraction of inspired oxygen, oxygenation index, or Sequential Organ Failure Assessment score. CONCLUSIONS: GSK2586881 was well-tolerated in patients with ARDS, and the rapid modulation of RAS peptides suggests target engagement, although the study was not powered to detect changes in acute physiology or clinical outcomes. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01597635 . Registered on 26 January 2012.

New setting of neurally adjusted ventilatory assist for noninvasive ventilation by facial mask: a physiologic study.

BACKGROUND: Noninvasive ventilation (NIV) is generally delivered using pneumatically-triggered and cycled-off pressure support (PSP) through a mask. Neurally adjusted ventilatory assist (NAVA) is the only ventilatory mode that uses a non-pneumatic signal, i.e., diaphragm electrical activity (EAdi), to trigger and drive ventilator assistance. A specific setting to generate neurally controlled pressure support (PSN) was recently proposed for delivering NIV by helmet. We compared PSN with PSP and NAVA during NIV using a facial mask, with respect to patient comfort, gas exchange, and patient-ventilator interaction and synchrony. METHODS: Three 30-minute trials of NIV were randomly delivered to 14 patients immediately after extubation to prevent post-extubation respiratory failure: (1) PSP, with an inspiratory support ≥8 cmH2O; (2) NAVA, adjusting the NAVA level to achieve a comparable peak EAdi (EAdipeak) as during PSP; and (3) PSN, setting the NAVA level at 15 cmH2O/µV with an upper airway pressure (Paw) limit to obtain the same overall Paw applied during PSP. We assessed patient comfort, peak inspiratory flow (PIF), time to reach PIF (PIFtime), EAdipeak, arterial blood gases, pressure-time product of the first 300 ms (PTP300-index) and 500 ms (PTP500-index) after initiation of patient effort, inspiratory trigger delay (DelayTR-insp), and rate of asynchrony, determined as asynchrony index (AI%). The categorical variables were compared using the McNemar test, and continuous variables by the Friedman test followed by the Wilcoxon test with Bonferroni correction for multiple comparisons (p < 0.017). RESULTS: PSN significantly improved patient comfort, compared to both PSP (p = 0.001) and NAVA (p = 0.002), without differences between the two latter (p = 0.08). PIF (p = 0.109), EAdipeak (p = 0.931) and gas exchange were similar between modes. Compared to PSP and NAVA, PSN reduced PIFtime (p < 0.001), and increased PTP300-index (p = 0.004) and PTP500-index (p = 0.001). NAVA and PSN significantly reduced DelayTR-insp, as opposed to PSP (p < 0.001). During both NAVA and PSN, AI% was <10% in all patients, while AI% was ≥10% in 7 patients (50%) with PSP (p = 0.023 compared with both NAVA and PSN). CONCLUSIONS: Compared to both PSP and NAVA, PSN improved comfort and patient-ventilator interaction during NIV by facial mask. PSN also improved synchrony, as opposed to PSP only. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03041402 . Registered (retrospectively) on 2 February 2017.

Initial blood pH during cardiopulmonary resuscitation in out-of-hospital cardiac arrest patients: a multicenter observational registry-based study.

BACKGROUND: When an out-of-hospital cardiac arrest (OHCA) patient receives cardiopulmonary resuscitation (CPR) in the emergency department (ED), blood laboratory test results can be obtained by using point-of-care testing during CPR. In the present study, the relationship between blood laboratory test results during CPR and outcomes of OHCA patients was investigated. METHODS: This study was a multicenter retrospective analysis of prospective registered data that included 2716 OHCA patients. Data from the EDs of three university hospitals in different areas were collected from January 2009 to December 2014. Univariate and multivariable analyses were conducted to elucidate the factors associated with survival to discharge and neurological outcomes. A final analysis was conducted by including patients who had no prehospital return of spontaneous circulation and those who underwent rapid blood laboratory examination during CPR. RESULTS: Overall, 2229 OHCA patients were included in the final analysis. Among them, the rate of survival to discharge and a good Cerebral Performance Categories Scale score were 14% and 4.4%, respectively. The pH level was independently related to survival to hospital discharge (adjusted OR 6.287, 95% CI 2.601-15.197; p < 0.001) and good neurological recovery (adjusted OR 15.395, 95% CI 3.439-68.911; p < 0.001). None of the neurologically intact patients had low pH levels (< 6.8) or excessive potassium levels (> 8.5 mEq/L) during CPR. CONCLUSIONS: Among the blood laboratory test results during CPR of OHCA patients, pH and potassium levels were observed as independent factors associated with survival to hospital discharge, and pH level was considered as an independent factor related to neurological recovery.

Effects of neurally adjusted ventilatory assist on air distribution and dead space in patients with acute exacerbation of chronic obstructive pulmonary disease.

BACKGROUND: Neurally adjusted ventilatory assist (NAVA) could improve patient-ventilator interaction; its effects on ventilation distribution and dead space are still unknown. The aim of this study was to evaluate the effects of varying levels of assist during NAVA and pressure support ventilation (PSV) on ventilation distribution and dead space in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD). METHODS: Fifteen mechanically ventilated patients with AECOPD were included in the study. The initial PSV levels were set to 10 cmH2O for 10 min. Thereafter, the ventilator mode was changed to NAVA for another 10 min with the same electrical activity of the diaphragm as during PSV. Furthermore, the ventilation mode was switched between PSV and NAVA every 10 min in the following order: PSV 5 cmH2O; NAVA 50%; PSV 15 cmH2O; and NAVA 150% (relative to the initial NAVA support level). Ventilation distribution in the lung was evaluated in percentages in regions of interest (ROI) of four anteroposterior segments of equal height (ROI1 to ROI4 represents ventral, mid-ventral, mid-dorsal, and dorsal, respectively). Blood gases, ventilation distribution (electrical impedance tomography), diaphragm activity (B-mode ultrasonography), and dead space fraction (PeCO2 and PaCO2) were measured. RESULTS: The trigger and cycle delays were lower during NAVA than during PSV. The work of trigger was significantly lower during NAVA compared to PSV. The diaphragm activities based on ultrasonography were higher during NAVA compared to the same support level during PSV. The ventilation distribution in ROI4 increased significantly (P < 0.05) during NAVA compared to PSV (except for a support level of 50%). Similar results were found in ROI3 + 4. NAVA reduced dead space fraction compared to the corresponding support level of PSV. CONCLUSIONS: NAVA was superior to PSV in AECOPD for increasing ventilation distribution in ROI4 and reducing dead space. TRIAL REGISTRATION: Clinicaltrials.gov, NCT02289573 . Registered on 12 November 2014.

Risk of death and readmission of hospital-admitted COPD exacerbations: European COPD Audit.

Studies report high in-hospital and post-discharge mortality of chronic obstructive pulmonary disease (COPD) exacerbations varying depending upon patient characteristics, hospital resources and treatment standards. This study aimed to investigate the patient, resource and organisational factors associated with in-hospital and 90-day post-discharge mortality and readmission of COPD exacerbations within the European COPD Audit. The audit collected data of COPD exacerbation admissions from 13 European countries.On admission, only 49.7% of COPD patients had spirometry results available and only 81.6% had blood gases taken. Using logistic regression analysis, the risk associated with in-hospital and post-discharge mortality was higher age, presence of acidotic respiratory failure, subsequent need for ventilatory support and presence of comorbidity. In addition, the 90-day risk of COPD readmission was associated with previous admissions. Only the number of respiratory specialists per 1000 beds, a variable related to hospital resources, decreased the risk of post-discharge mortality.The European COPD Audit identifies risk factors associated with in-hospital and post-discharge mortality and COPD readmission. Addressing the deficiencies in acute COPD care such as making spirometry available and measuring blood gases and providing noninvasive ventilation more regularly would provide opportunities to improve COPD outcomes.

Hydrocortisone treatment in early sepsis-associated acute respiratory distress syndrome: results of a randomized controlled trial.

BACKGROUND: Authors of recent meta-analyses have reported that prolonged glucocorticoid treatment is associated with significant improvements in patients with severe pneumonia or acute respiratory distress syndrome (ARDS) of multifactorial etiology. A prospective randomized trial limited to patients with sepsis-associated ARDS is lacking. The objective of our study was to evaluate the efficacy of hydrocortisone treatment in sepsis-associated ARDS. METHODS: In this double-blind, single-center (Siriraj Hospital, Bangkok), randomized, placebo-controlled trial, we recruited adult patients with severe sepsis within 12 h of their meeting ARDS criteria. Patients were randomly assigned (1:1 ratio) to receive either hydrocortisone 50 mg every 6 h or placebo. The primary endpoint was 28-day all-cause mortality; secondary endpoints included survival without organ support on day 28. RESULTS: Over the course of 4 years, 197 patients were randomized to either hydrocortisone (n = 98) or placebo (n = 99) and were included in this intention-to-treat analysis. The treatment group had significant improvement in the ratio of partial pressure of oxygen in arterial blood to fraction of inspired oxygen and lung injury score (p = 0.01), and similar timing to removal of vital organ support (HR 0.74, 95 % CI 0.51-1.07; p = 0.107). After adjustment for significant covariates, day 28 survival was similar for the whole group (HR 0.80, 95 % CI 0.46-1.41; p = 0.44) and for the larger subgroup (n = 126) with Acute Physiology and Chronic Health Evaluation II score <25 (HR 0.57, 95 % CI 0.24-1.36; p = 0.20). With the exception of hyperglycemia (80.6 % vs. 67.7 %; p = 0.04), the rate of adverse events was similar. Hyperglycemia had no impact on outcome. CONCLUSIONS: In sepsis-associated ARDS, hydrocortisone treatment was associated with a significant improvement in pulmonary physiology, but without a significant survival benefit. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT01284452 . Registered on 18 January 2011.

Effect of Coronary Artery Bypass Grafting Surgery on Pulmonary Function Tests and Arterial Blood Gases.

BACKGROUND AND OBJECTIVE: Pulmonary dysfunction after open heart surgery is an important cause of post-operative morbidity. To evaluate effect of coronary artery bypass grafting (CABG) surgery on pulmonary functions and arterial blood gases (ABGs). METHODS: A prospective study was conducted at a pulmonary unit of a tertiary care public hospital. Of the 50, patients enrolled, 42 patients completed the study. Spirometry was performed one week pre-operatively and within four to five weeks post-operatively. Arterial blood gas samples were also collected just before spirometry. The pre- and post-operative data were compared. RESULTS: There was significant reduction in forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) by 13.8% and 13.1%, respectively within five weeks of surgery. After surgery mean maximum voluntary ventilation (MVV) showed a significant decrease of 7.6%. Post-operatively, the mean pH decreased significantly by 0.1% and the mean partial pressure of oxygen (PaO2) and oxygen saturation SpO2-showed significant decrease of 10.1% and 2.4%, respectively. CONCLUSION: Coronary artery bypass grafting has an adverse impact on lung functions and ABGs.