FiO2 Ratio Research Articles

Effect of flow-optimized pressure control ventilation-volume guaranteed (PCV-VG) on postoperative pulmonary complications: a consort study

BackgroundPostoperative pulmonary complications (PPCs) after one-lung ventilation (OLV) significantly impact patient prognosis and quality of life.ObjectiveTo study the impact of an optimal inspiratory flow rate on PPCs in thoracic surgery patients.MethodsOne hundred eight elective thoracic surgery patients were randomly assigned to 2 groups in this consort study (control group: n = 53 with a fixed inspiratory expiratory ratio of 1:2; and experimental group [flow rate optimization group]: n = 55). Measurements of Ppeak, Pplat, PETCO2, lung dynamic compliance (Cdyn), respiratory rate, and oxygen concentration were obtained at the following specific time points: immediately after intubation (T0); immediately after starting OLV (T1); 30 min after OLV (T2); and 10 min after 2-lung ventilation (T4). The PaO2:FiO2 ratio was measured using blood gas analysis 30 min after initiating one-lung breathing (T2) and immediately when OLV ended (T3). The lung ultrasound score (LUS) was assessed following anesthesia and resuscitation (T5). The occurrence of atelectasis was documented immediately after the surgery. PPCs occurrences were noted 3 days after surgery.ResultsThe treatment group had a significantly lower total prevalence of PPCs compared to the control group (3.64% vs. 16.98%; P = 0.022). There were no notable variations in peak airway pressure, airway plateau pressure, dynamic lung compliance, PETCO2, respiratory rate, and oxygen concentration between the two groups during intubation (T0). Dynamic lung compliance and the oxygenation index were significantly increased at T1, T2, and T4 (P < 0.05), whereas the CRP level and number of inflammatory cells decreased dramatically (P < 0.05).ConclusionOptimizing inspiratory flow rate and utilizing pressure control ventilation -volume guaranteed (PCV-VG) mode can decrease PPCs and enhance lung dynamic compliance in OLV patients.

Effect of continuous positive airway pressure helmet on respiratory function following surgical procedures in brachycephalic dogs: A randomized controlled trial.

To evaluate the effect of continuous positive airway pressure (CPAP) on respiratory function in the early postoperative period of brachycephalic dogs. Prospective, randomized clinical trial. A total of 32 dogs. Dogs were assigned to recover with or without CPAP (control) and assessed at specific time points over 1 h. Treatment was discontinued for dogs with a CPAP tolerance score of 3 or more (from a range of 0-4). The primary outcome was pulse oximetry (SpO2). Secondary outcomes were arterial O2 pressure (PaO2)/FiO2 ratio (PaO2/FiO2), arterial CO2 pressure (PaCO2), and rectal temperature. For dogs that reached a CPAP tolerance score of 3 or more, only the data collected up to the time point before discontinuation were included in the analysis.The treatment effect (β) was analyzed using random effects models and the results were reported with 95% confidence intervals. Dogs were assigned randomly to each protocol. Baseline characteristics in both groups were comparable. Arterial blood gases were obtained in seven control group dogs and nine CPAP group dogs. Treatment did not affect SpO2 (β = -0.1, -2.1 to 2.0) but affected the PaO2/FiO2 ratio (β = 58.1, 2.6 to 113.6), with no effects on PaCO2 (β = -4.3, -10.5 to 1.9) or temperature (β = 0.4, -0.8 to 1.6). In postoperative brachycephalic dogs, CPAP had no effect on SpO2 but improved the PaO2/FiO2 ratio in brachycephalic dogs postoperatively. Continuous positive airway pressure offers a valuable solution to improve gas exchange efficiency, a prevalent concern in postoperative brachycephalic dogs, with the potential to enhance overall outcomes.

SCARLET (Supplemental Citicoline Administration to Reduce Lung injury Efficacy Trial): study protocol for a single-site, double-blinded, placebo-controlled, and randomized Phase 1/2 trial of i.v. citicoline (CDP-choline) in hospitalized SARS CoV-2-infected patients with hypoxemic acute respiratory failure

BackgroundThe SARS CoV-2 pandemic has resulted in more than 1.1 million deaths in the USA alone. Therapeutic options for critically ill patients with COVID-19 are limited. Prior studies showed that post-infection treatment of influenza A virus-infected mice with the liponucleotide CDP-choline, which is an essential precursor for de novo phosphatidylcholine synthesis, improved gas exchange and reduced pulmonary inflammation without altering viral replication. In unpublished studies, we found that treatment of SARS CoV-2-infected K18-hACE2-transgenic mice with CDP-choline prevented development of hypoxemia. We hypothesize that administration of citicoline (the pharmaceutical form of CDP-choline) will be safe in hospitalized SARS CoV-2-infected patients with hypoxemic acute respiratory failure (HARF) and that we will obtain preliminary evidence of clinical benefit to support a larger Phase 3 trial using one or more citicoline doses.MethodsWe will conduct a single-site, double-blinded, placebo-controlled, and randomized Phase 1/2 dose-ranging and safety study of Somazina® citicoline solution for injection in consented adults of any sex, gender, age, or ethnicity hospitalized for SARS CoV-2-associated HARF. The trial is named “SCARLET” (Supplemental Citicoline Administration to Reduce Lung injury Efficacy Trial). We hypothesize that SCARLET will show that i.v. citicoline is safe at one or more of three doses (0.5, 2.5, or 5 mg/kg, every 12 h for 5 days) in hospitalized SARS CoV-2-infected patients with HARF (20 per dose) and provide preliminary evidence that i.v. citicoline improves pulmonary outcomes in this population. The primary efficacy outcome will be the SpO2:FiO2 ratio on study day 3. Exploratory outcomes include Sequential Organ Failure Assessment (SOFA) scores, dead space ventilation index, and lung compliance. Citicoline effects on a panel of COVID-relevant lung and blood biomarkers will also be determined.DiscussionCiticoline has many characteristics that would be advantageous to any candidate COVID-19 therapeutic, including safety, low-cost, favorable chemical characteristics, and potentially pathogen-agnostic efficacy. Successful demonstration that citicoline is beneficial in severely ill patients with SARS CoV-2-induced HARF could transform management of severely ill COVID patients.Trial registrationThe trial was registered at www.clinicaltrials.gov on 5/31/2023 (NCT05881135).Trial statusCurrently enrolling.

Emergency Department SpO2/FiO2 Ratios Correlate with Mechanical Ventilation and Intensive Care Unit Requirements in COVID-19 Patients.

Patients with coronavirus 2019 (COVID-19) are at high risk for respiratory dysfunction. The pulse oximetry/fraction of inspired oxygen (SpO2/FiO2) ratio is a non-invasive assessment of respiratory dysfunction substituted for the PaO2:FiO2 ratio in Sequential Organ Failure Assessment scoring. We hypothesized that emergency department (ED) SpO2/FiO2 ratios correlate with requirement for mechanical ventilation in COVID-19 patients. Our objective was to identify COVID-19 patients at greatest risk of requiring mechanical ventilation, using SpO2/FiO2 ratios. We performed a retrospective review of patients admitted with COVID-19 at two hospitals. Highest and lowest SpO2/FiO2 ratios (percent saturation/fraction of inspired O2) were calculated on admission. We performed chi-square, univariate, and multiple regression analysis to evaluate the relationship of admission SpO2/FiO2 ratios with requirement for mechanical ventilation and intensive care unit (ICU) care. A total of 539 patients (46% female; 84% White), with a mean age 67.6 ± 18.6years, met inclusion criteria. Patients who required mechanical ventilation during their hospital stay were statistically younger in age (P = 0.001), had a higher body mass index (P < .001), and there was a higher percentage of patients who were obese (P = 0.03) and morbidly obese (P < .001). Shortness of breath, cough, and fever were the most common presenting symptoms with a median temperature of 99°F. Average white blood count was higher in patients who required ventilation (P = <0.001). A highest obtained ED SpO2/FiO2 ratio of ≤300 was associated with a requirement for mechanical ventilation. A lowest obtained ED SpO2/FiO2 ratio of ≤300 was associated with a requirement for intensive care unit care. There was no statistically significant correlation between ED SpO2/FiO2 ratios >300 and mechanical ventilation or intensive care unit (ICU) requirement. The ED SpO2/FiO2 ratios correlated with mechanical ventilation and ICU requirements during hospitalization for COVID-19. These results support ED SpO2/FiO2 as a possible triage tool and predictor of hospital resource requirements for patients admitted with COVID-19. Further investigation is warranted.

A Recruitment Maneuver After Apnea Testing Improves Oxygenation and Reduces Atelectasis in Organ Donors After Brain Death.

Hypoxemia is the main modifiable factor preventing lungs from being transplanted from organ donors after brain death. One major contributor to impaired oxygenation in patients with brain injury is atelectasis. Apnea testing, an integral component of brain death declaration, promotes atelectasis and can worsen hypoxemia. In this study, we tested whether performing a recruitment maneuver (RM) after apnea testing could mitigate hypoxemia and atelectasis. During the study period, an RM (positive end-expiratory pressure of 15cm H2O for 15s then 30cm H2O for 30s) was performed immediately after apnea testing. We measured partial pressure of oxygen, arterial (PaO2) before and after RM. The primary outcomes were oxygenation (PaO2 to fraction of inspired oxygen [FiO2] ratio) and the severity of radiographic atelectasis (proportion of lung without aeration on computed tomography scans after brain death, quantified using an image analysis algorithm) in those who became organ donors. Outcomes in RM patients were compared with control patients undergoing apnea testing without RM in the previous 2years. Recruitment maneuver was performed in 54 patients after apnea testing, with a median immediate increase in PaO2 of 63mm Hg (interquartile range 0-109, p = 0.07). Eighteen RM cases resulted in hypotension, but none were life-threatening. Of this cohort, 37 patients became organ donors, compared with 37 donors who had apnea testing without RM. The PaO2:FiO2 ratio was higher in the RM group (355 ± 129 vs. 288 ± 127, p = 0.03), and fewer had hypoxemia (PaO2:FiO2 ratio < 300mm Hg, 22% vs. 57%; p = 0.04) at the start of donor management. The RM group showed less radiographic atelectasis (median 6% vs. 13%, p = 0.045). Although there was no difference in lungs transplanted (35% vs. 24%, p = 0.44), both better oxygenation and less atelectasis were associated with a higher likelihood of lungs being transplanted. Recruitment maneuver after apnea testing reduces hypoxemia and atelectasis in organ donors after brain death. This effect may translate into more lungs being transplanted.

Effects of Different Extubation Strategies on Atelectasis in Older Adults after Major Abdominal Surgery: A Prospective Randomized Controlled Trial.

Older patients are particularly vulnerable to age-related respiratory changes. This prospective randomized controlled trial studied the effects of high and low fractions of inspired oxygen (FiO2) with the recruitment maneuver (RM) during extubation on lung atelectasis postoperatively in older patients undergoing major abdominal surgery. We randomized a total of 126 patients aged &gt;60 years who underwent both elective and emergency major abdominal surgeries and met the inclusion criteria into three groups (H, HR, and LR) using computer-generated block randomization. Group H received high FiO2 (1), Group HR received high FiO2 (1) with RM followed by a positive end-expiratory pressure of 5 cm H2O, and Group LR received low FiO2 (0.4) with RM followed by a positive end-expiratory pressure of 5 cm H2O 10 minutes before extubation. Oxygenation and atelectasis were measured using the arterial partial pressure of oxygen (PaO2)/FiO2 ratios and lung ultrasound score. Postoperative pulmonary complications were recorded up to 24 hours postoperatively. The mean PaO2/FiO2 at 30 minutes post-extubation was significantly higher in Groups LR and HR compared to that in Group H (390.71±29.55, 381.97±24.97, and 355.37±31.70; p&lt;0.001). In the immediate postoperative period, the median lung ultrasound score was higher in Group H than that in Groups LR and HR (6 [5-7], 3 [3-5], and 3.5 [2.25-4.75]; p&lt;0.001). The incidence of oxygen desaturation and oxygen requirements was higher in Group H during the postoperative period. The RM before extubation is beneficial in reducing atelectasis and postoperative pulmonary complications, irrespective of the FiO2 concentration used in older adults undergoing major abdominal surgeries. (Trail registration number: Reference No. CTRI/2022/04/042115; date of CTRI registration 25/02/2022; and date of enrolment of the first research participant 05/05/2022).

Measurement of lung oxygenation by near-infrared spectroscopy in preterm infants with bronchopulmonary dysplasia.

It has recently been reported that it is possible to monitor lung oxygenation (rSO2L) by near-infrared spectroscopy (NIRS) in preterm infants with respiratory distress syndrome (RDS). Thus, our aim was to assess the possibility of monitoring rSO2L in infants with evolving and established bronchopulmonary dysplasia (BPD) and to evaluate if rSO2L correlates with BPD severity and other oxygenation indices. We studied 40 preterm infants with gestational age ≤30 weeks at risk for BPD. Patients were continuously studied for 2 h by NIRS at 28 ± 7 days of life and 36 weeks ± 7 days of postmenstrual age. rSO2L was similar at the first and second NIRS recordings (71.8 ± 7.2 vs. 71.4 ± 4.2%) in the overall population, but it was higher in infants with mild than in those with moderate-to-severe BPD at both the first (73.3 ± 3.1 vs. 71.2 ± 3.2%, p = .042) and second (72.3 ± 2.8 vs. 70.5 ± 2.8, p = .049) NIRS recording. A rSO2L cutoff value of 71.6% in the first recording was associated with a risk for moderate-to-severe BPD with a sensitivity of 66% and a specificity of 60%. Linear regression analysis demonstrated a significant positive relationship between rSO2L and SpO2/FiO2 ratio (p = .013) and a/APO2 (p = .004). Monitoring of rSO2L by NIRS in preterm infants with evolving and established BPD is feasible and safe. rSO2L was found to be higher in infants with mild BPD, and predicts the risk for developing moderate-to-severe BPD and correlates with other indices of oxygenation.

Utilization of peritoneal dialysis for ventilated COVID-19 patients with acute kidney injury

BackgroundPeritoneal dialysis for acute kidney injury is not typically a first-line option for mechanically ventilated patients in the intensive care unit. This series investigates the technical feasibility and clinical implications of bedside peritoneal dialysis catheter placement and utilization for mechanically ventilated COVID-19 patients. MethodsPatient data was retrospectively collected on patient characteristics, hospital course, fluid balance, ventilatory mechanics and associated morbidity and mortality of qualifying patients at a single center from March to April of 2020. Peritoneal dialysis catheters were inserted at bedside in the ICU for use as the primary modality of renal replacement therapy. Ventilatory mechanics were obtained prior to catheter insertion and after the first dwell. Statistics were calculated using GraphPad Prism and Excel. ResultsSeven male ventilated patients ages 52–83 were included. They were primarily Hispanic (71.43%). Comorbidities included chronic kidney disease (14.29%), hypertension (57.14%), hyperlipidemia (42.86%), and diabetes (28.57%). There were no mortalities associated the procedure. All-cause mortality at the time of data collection was 42.8%. Two patients had delayed initiation of peritoneal dialysis due to bleeding. Ventilatory mechanics before and after the first dwell did not demonstrate a significant difference in required FiO2, PEEP, tidal volumes or PaO2 to FiO2 ratios (p = 0.9172, p = 0.7398, p = 0.0924, p = 0.7227). DiscussionBedside placement of catheters was performed quickly and safely. Peritoneal dialysis was utilized for the treatment of acute kidney injury in mechanically ventilated patients with COVID-19 without significantly impacting respiratory mechanics. Peritoneal dialysis should be considered for similar ICU patients needing renal replacement therapy.

Comparison of Fixed Dosing vs Train of Four Titration of Cisatracurium in COVID-19 ARDS Patients

Background: Early neuromuscular blockade with cisatracurium has been associated with improved outcomes in moderate-severe acute respiratory distress syndrome (ARDS). Previous studies have demonstrated increased drug utilization without benefits in oxygenation using fixed dose cisatracurium compared to train-of-four (TOF) titration. Objective: We sought to compare a novel, lower fixed dose cisatracurium protocol to TOF titration evaluating the impact on PaO2:FiO2 ratio (P/F). Methods: We conducted a single-center retrospective cohort study comparing fixed dose cisatracurium to TOF titration. We included patients aged 18-89 treated for COVID-19 ARDS with a baseline P/F≤200 who received a cisatracurium infusion for ≥12 h. The primary outcome was change in P/F at 48 h from baseline. Secondary outcomes included change in P/F at 24 h and 7 days, need for mechanical ventilation at day 28, and cisatracurium utilization. Results: Analyses included 125 patients (fixed dose = 65, TOF = 60). Severe ARDS was common with a baseline median P/F of 73.7 vs 79.5, P = .133. The change in P/F at 48 h was larger in the TOF cohort in the adjusted analysis (24.9 vs 70.8, P < .005). The rate and total cumulative dose of cisatracurium were higher in the fixed dose cohort (5 vs 3 mcg/kg/min, P < .001; 1034 vs 612 mg, P < .001) despite similar infusion durations (44.1 h vs 48.5 h, P = .642). Conclusions: Patients in the TOF cisatracurium cohort had improved P/F at 48 h compared to the fixed dose cohort, while also using only 60% of the cumulative dose. Future directions should include analysis of the implications of increased cisatracurium exposure on patient outcomes.

Influence of inflammatory factors (IL-6, CRP, NLPR, D-Dimer, LDH) on the PaO2/FiO2 ratio, in patients with severe and critical degrees of COVID-19

BACKGROUND: Several types of inflammatory biomarkers that are important in severe and critical Covid-19 infections include: levels of IL-6, C-reactive protein (CRP), lactate dehydrogenase (LDH), D-Dimer and neutrophil-lymphocyte platelet ratio (NLRP), which are independent variables. Meanwhile, the severity of Covid-19 infection can be determined by measuring the PaO2 /FiO2 ratio. However, the relationship between the PaO2/FiO2 ratio as the dependent variable is not yet known. AIMS: To analyze the relationship between PaO2/FiO2 ratio and inflammatory biomarkers in COVID-19 patients METHOD: An analytic observational study with a retrospective, cross-sectional approach. The research sample consisted of PCR-confirmed severe and critical COVID-19 patients who were treated in the isolation room of the Ulin Hospital in Banjarmasin from August–December 2021, who met the inclusion and exclusion criteria. Data analysis used the Spearman test to see the relationship between the PaO2/FiO2 ratio and various inflammatory markers. RESULT: 52 severe and critical patients were observed according to the research flow. The number of male and female subjects (32/20) was found. The mean age was 55.38 years. The correlation test found that: there was no significant relationship between the PaO2/FiO2 ratio and IL-6 (p = 0.964), but there was a negative correlation between the PaO2/FiO2 ratio and: a).CRP (p = 0.038), b).LDH ( p&lt;0.001), c).NLPR (p = 0.013), and d). D-dimer (p&lt;0.001). The inflammatory biomarkers NLPR, LDH, and D-dimer are important independent variables for the severity of COVID-19, namely the PaO2/FiO2 ratio. CONCLUSION: There are a significant correlation between the PaO2/FiO2 ratio to measure the severity of Covid-19 and several inflammatory biomarkers CRP, LDH, NLPR and D-dimer

Magnitude and time to peak oxygenation effect of prone positioning in ventilated adults with COVID-19 related acute hypoxemic respiratory failure.

Prone positioning may improve oxygenation in acute hypoxemic respiratory failure and was widely adopted in COVID-19 patients. However, the magnitude and timing of its peak oxygenation effect remain uncertain with the optimum dosage unknown. Therefore, we aimed to investigate the magnitude of the peak effect of prone positioning on the PaO2 :FiO2 ratio during prone and secondly, the time to peak oxygenation. Multi-centre, observational study of invasively ventilated adults with acute hypoxemic respiratory failure secondary to COVID-19 treated with prone positioning. Baseline characteristics, prone positioning and patient outcome data were collected. All arterial blood gas (ABG) data during supine, prone and after return to supine position were analysed. The magnitude of peak PaO2 :FiO2 ratio effect and time to peak PaO2 :FIO2 ratio effect was measured. We studied 220 patients (mean age 54 years) and 548 prone episodes. Prone positioning was applied for a mean (±SD) 3 (±2) times and 16 (±3) hours per episode. Pre-proning PaO2 :FIO2 ratio was 137 (±49) for all prone episodes. During the first episode. the mean PaO2 :FIO2 ratio increased from 125 to a peak of 196 (p < .001). Peak effect was achieved during the first episode, after 9 (±5) hours in prone position and maintained until return to supine position. In ventilated adults with COVID-19 acute hypoxemic respiratory failure, peak PaO2 :FIO2 ratio effect occurred during the first prone positioning episode and after 9 h. Subsequent episodes also improved oxygenation but with diminished effect on PaO2 :FIO2 ratio. This information can help guide the number and duration of prone positioning episodes.

Acute Respiratory Failure Complicating Endoscopic Sleeve Gastroplasty: A Case Report.

Endoscopic sleeve gastroplasty (ESG) is a safe and minimally invasive procedure for the treatment of obesity. We report the case of a patient with obesity who underwent ESG complicated by postprocedural respiratory failure. During the procedure, she developed a Pao2/fraction of inspired oxygen (Fio2) ratio that necessitated postoperative mechanical ventilation. Chest radiography demonstrated massively dilated loops of bowel, cephalad displacement of both hemidiaphragms, lung volume reduction, and atelectasis. With absorption of luminal carbon dioxide, she was weaned from mechanical ventilation to supplemental oxygen, and she recovered completely. This case highlights postoperative respiratory failure associated with mechanical loading of the respiratory system following ESG.

Modified Sick Neonatal Score (MSNS) in Predicting the Outcome of Neonates in Tertiary Care Hospital

Introduction: Neonatal disease severity scoring systems are widely used to predict severity of illness. Existing scoring systems contain variables like pH, PO2 / FiO2 ratio, and base excess, which are difficult to obtain in resource-limited settings. Modified sick neonatal score (MSNS) is based on eight clinical variables which are easy to calculate and are also accurate enough at the same time. This study was done to evaluate MSNS for predicting the outcome of neonates in our settings.&#x0D; Methods: This was prospective observational study done at neonatal intensive care unit (NICU) of tertiary care hospital in Nepal from February 2021 to January 2022. The parameters required for the score were recorded at admission. Total score was calculated and outcome was noted. Data collected was analyzed using SPSS Statistics for Windows, v21.0. Chi square test, Mann-Whitney U test and ROC analysis were used for statistical analysis.&#x0D; Results: Total of 195 neonates were discharged and 37 expired. The mean MSNS score among expired was 8.16 ± 1.625 and discharged was 10.99 ± 1.753. For a cutoff score of ≤ 10, sensitivity and specificity; Positive and negative predictive value were 89.2% and 60.5%; 30.7% and 98.3% respectively. The area under the curve (AUC) of MSNS was 0.875 (CI 95%; 0.817 - 0.934). Lower MSNS score was also associated with requirement of iontrope and ventilator support.&#x0D; Conclusions: MSNS can be used as an important clinical tool for predicting the severity of disease in neonates in resource limited settings.

The Prone Position Improves the Oxygenation Status of Patients with COVID-19 (Systematic Review-Meta Analysis)

Hypoxemia in Corona Virus 19 patients requires supportive and rehabilitative treatment. PP is a technique that is considered to be safe for improving patient oxygenation. This review aimed to determine a cumulative effect of PP on oxygenation status in COVID-19 patients.The method used The search was carried out independently and systematically on the ProQuest, PubMed, Science Direct, Google Scholar and Semantic Scholar databases from January 2020, until June 2022. Article screening was carried out through 3 stages: screening duplicate articles, titles and abstracts, and full-text screening by the expected criteria with preferred Items for PRISMA Standards. The quality assessment of the article uses the Joanna Briggs Institute (JBI) checklist form and the Review Manager software. The results A total of 323 articles were evaluated using an RCT or Quasi Experiment design with a control group. It was found that PP had an influence on changes in the value of the ROX index, PaO2/ FiO2 Ratio, SPO2, and SaO2 / FiO2 Ratio with p-value 0.05. Qualitatively, several positive results were obtained from the synthesis of each research. PP was assessed using a ventilation-perfusion matching mechanism in increasing oxygenation and preventing lung injuries.It is concluded that PP was considered safe even though it caused side effects but it could still be done with good monitoring from health providers.

Awake prone positioning for COVID-19 acute hypoxemic respiratory failure in Tunisia.

In this study, we explored whether awake prone position (PP) can impact prognosis of severe hypoxemia coronavirus disease 2019 (COVID-19) patients. This was a prospective observational study of severe, critically ill adult COVID-19 patients admitted to the intensive care unit. Patients were divided into two groups: group G1, patients who benefited from a vigilant and effective PP (>4 hours minimum/24) and group G2, control group. We compared demographic, clinical, paraclinical and evolutionary data. Three hundred forty-nine patients were hospitalized during the study period, 273 met the inclusion criteria. PP was performed in 192 patients (70.3%). The two groups were comparable in terms of demographic characteristics, clinical severity and modalities of oxygenation at intensive care unit (ICU) admission. The mean PaO2/ FIO2 ratios were 141 and 128 mm Hg, respectively (P=0.07). The computed tomography scan was comparable with a critical >75% in 48.5% (G1) versus 54.2% (G2). The median duration of the daily PP session was 13±7 hours per day. The average duration of spontaneous PP days was 7 days (4-19). Use of invasive ventilation was lower in the G1 group (27% vs. 56%, P=0.002). Healthcare-associated infections were significantly lower in G1 (42.1% vs. 82%, P=0.01). Duration of total mechanical ventilation and length of ICU stay were comparable between the two groups. Mortality was significantly higher in G2 (64% vs. 28%, P=0.02). Our study confirmed that awake PP can improve prognosis in COVID-19 patients. Randomized controlled trials are needed to confirm this result.

Reduced pulmonary oxygen diffusion at 36 weeks of postmenstrual age in small-for-gestational-age preterm infants of less than 32 weeks without bronchopulmonary dysplasia.

Small-for-gestational-age (SGA) preterm infants are at increased risk of developing bronchopulmonary dysplasia (BPD). There is limited information on pulmonary oxygen diffusion of SGA preterm infants, particularly in those without BPD. To compare the pulmonary oxygen diffusion of SGA to that of appropriate-for-gestational-age (AGA) preterm infants without BPD. Preterm infants with a gestational age (GA) between 24.0 and 31.6 weeks were studied. The oxygen saturation (SpO2 ), fraction to inspired oxygen (FiO2 ), and the SpO2 to FiO2 ratio (SFR) were compared between SGA and AGA infants. The association between SGA and SFR at 36 weeks was assessed using a multiple regression analysis. In the subgroup without BPD, SGA were match-paired for GA and gender with AGA infants. We analyzed 1189 infants surviving at 36 weeks: 194 (16%) were SGA and 995 (84%) AGA. The incidence of BPD was significantly higher in SGA than AGA infants (32% vs. 13%; p = .000). Out of the 995 infants without BPD, 132 (13%) were SGA and 863 (87%) AGA. SGA was negatively associated with the SFR value at 36 weeks, independently from BPD. SGA infants without BPD had significantly higher (better) SFR at birth, but lower (worse) SpO2 and SFR and from 33 to 36 weeks than their matched AGA counterpart. At 36 weeks, median SpO2 and SFR values were 97.7 versus 98.4 (p = .006) and 465 versus 468 (p = .010) in match-paired SGA and AGA, respectively. Among preterm infants of less than 32 weeks and without BPD, SGA infants had a reduced pulmonary oxygen diffusion at 36 weeks in comparison with AGA infants.

Vitamin D Deficiency in COVID-19 Patients and Role of Calcifediol Supplementation.

Hypovitaminosis D has been associated with worse outcome in respiratory tract infections, with conflicting opinions regarding its role in Coronavirus-19 disease (COVID-19). Our study aimed to evaluate the possible relationship between 25-OH vitamin D (25OHD) values and the following conditions in patients hospitalized for COVID-19: prognosis, mortality, invasive (IV) and non-invasive (NIV) mechanical ventilation, and orotracheal intubation (OTI). A further objective was the analysis of a possible positive effect of supplementation with calcifediol on COVID-19 severity and prognosis. We analyzed 288 patients hospitalized at the San Giovanni di Dio Hospital in Florence and the Santa Maria alle Scotte Hospital in Siena, from November 2020 to February 2021. The 25OHD levels correlated positively with the partial pressure of oxygen and FiO2 (PaO2/FiO2) ratio (r = 0.17; p < 0.05). Furthermore, when we analyzed the patients according to the type of respiratory support, we found that 25OHD levels were markedly reduced in patients who underwent non-invasive ventilation and orotracheal intubation (OTI). The evaluation of the length of hospitalization in our population evidenced a longer duration of hospitalization in patients with severe 25OHD deficiency (<10 ng/mL). Moreover, we found a statistically significant difference in the mortality rate between patients who had 25OHD levels below 10 ng/mL and those with levels above this threshold in the total population (50.8% vs. 25.5%, p = 0.005), as well as between patients with 25OHD levels below 20 ng/mL and those with levels above that threshold (38.4% vs. 24.6%, p = 0.04). Moreover, COVID-19 patients supplemented with calcifediol presented a significantly reduced length of hospitalization (p < 0.05). Interestingly, when we analyzed the possible effects of calcifediol on mortality rate in patients with COVID-19, we found that the percentage of deaths was significantly higher in patients who did not receive any supplementation than in those who were treated with calcifediol (p < 0.05) In conclusion, we have demonstrated with our study the best prognosis of COVID-19 patients with adequate vitamin D levels and patients treated with calcifediol supplementation.

Discordance Between Invasive and NonInvasive Oxygen Saturation in Critically Ill COVID-19 Patients.

To investigate discordance in oxy-hemoglobin saturation measured both by pulse oximetry (SpO2) and arterial blood gas (ABG, SaO2) among critically ill coronavirus disease 2019 (COVID-19(+)) patients compared to COVID-19(-) patients. Paired SpO2 and SaO2 readings were collected retrospectively from consecutive adult admissions to four critical care units in the United States between March and May 2020. The primary outcome was the rate of discordance (|SaO2-SpO2|>4%) in COVID-19(+) versus COVID-19(-) patients. The odds each cohort could have been incorrectly categorized as having a PaO2/FiO2 above or below 150 by their SpO2: Fractional inhaled oxygen ratio (pulse oximetry-derived oxyhemoglobin saturation:fraction of inspired oxygen ratio [SF]) was examined. A multivariate regression analysis assessed confounding by clinical differences between cohorts including pH, body temperature, renal replacement therapy at time of blood draw, and self-identified race. There were 263 patients (173 COVID-19(+)) included. The rate of saturation discordance between SaO2 and SpO2 in COVID-19(+) patients was higher than in COVID-19(-) patients (27.9% vs 16.7%, odds ratio [OR] 1.94, 95% confidence interval [CI]: 1.11 to 2.27). The average difference between SaO2 and SpO2 for COVID-19(+) patients was -1.24% (limits of agreement, -13.6 to 11.1) versus -0.11 [-10.3 to 10.1] for COVID-19(-) patients. COVID-19(+) patients had higher odds (OR: 2.61, 95% CI: 1.14-5.98) of having an SF that misclassified that patient as having a PaO2:FiO2 ratio above or below 150. There was not an association between discordance and the confounders of pH, body temperature, or renal replacement therapy at time of blood draw. After controlling for self-identified race, the association between COVID-19 status and discordance was lost. Pulse oximetry was discordant with ABG more often in critically ill COVID-19(+) than COVID-19(-) patients. However, these findings appear to be driven by racial differences between cohorts.

Effects of adding the second drainage cannula in severely hypoxemic patients supported with VV ECMO due to COVID-19-associated ARDS.

Extracorporeal membrane oxygenation (ECMO) is a recognized method of support in patients with severe and refractory acute respiratory distress syndrome (ARDS) caused by SARS-CoV-2 infection. While veno-venous (VV) ECMO is the most common type, some patients with severe hypoxemia may require modifications to the ECMO circuit. In this study, we aimed to investigate the effects of adding a second drainage cannula to the circuit in patients with refractory hypoxemia, on their gas exchange, mechanical ventilation, ECMO settings, and clinical outcomes. We conducted an observational retrospective study based on a single-center institutional registry including all consecutive cases of COVID-19 patients requiring ECMO admitted to the Centre of Extracorporeal Therapies in Warsaw between March 1, 2020 and March 1, 2022. We selected patients who had an additional drainage cannula inserted. Changes in ECMO and ventilator settings, blood oxygenation, and hemodynamic parameters, as well as clinical outcomes were assessed. Of 138 VV ECMO patients, 12 (9%) patients met the inclusion criteria. Ten patients (83%) were men, and mean age was 42.2 ± 6.8. An addition of drainage cannula resulted in a significant raise in ECMO blood flow (4.77 ± 0.44 to 5.94 ± 0.81 [L/min]; p = 0.001), and the ratio of ECMO blood flow to ECMO pump rotations per minute (RPM), whereas the raise in ECMO RPM alone was not statistically significant (3432 ± 258 to 3673 ± 340 [1/min]; p = 0.064). We observed a significant drop in ventilator FiO2 and a raise in PaO2 to FiO2 ratio, while blood lactates did not change significantly. Nine patients died in hospital, one was referred to lung transplantation center, two were discharged uneventfully. The use of an additional drainage cannula in severe ARDS associated with COVID-19 allows for an increased ECMO blood flow and improved oxygenation. However, we observed no further improvement in lung-protective ventilation and poor survival.

Lung Ultrasound and Non-Invasive Ventilation Outcome in Acute Respiratory Failure

Objective: This study aimed to assess the diaphragmatic dysfunction in critically ill non-intubated patients admitted to respiratory critical care unit with acute respiratory failure.&#x0D; Methods: This was a prospective study conducted on 200 mechanically ventilated patients. The following data were collected: demographic characteristics, anthropometric measurements. Disease severity and hemodynamics. In addition, ICU length of stay, duration mechanical ventilation, outcome and duration of hospital stay. Besides, parameters of MV like (PaO2 / FiO2 Ratio), and respiratory rate were noticed. The laboratory workup included arterial blood gases, Na+, K+, Mg++, Ca++, PH, PCO2, HCO3-. The ultrasound was performed before and after weaning and included the diaphragmatic excursion and diaphragmatic thickness traction. The patients were split into two categories regarding their reaction to weaning attempts: Category A represented successful weaning. Category B represented unsuccessful weaning followed by reintubation and mechanically ventilated.&#x0D; Results: The weaning success was reported for 123 patients (61.5%) and mortality reported for 28 patients (14.0%). Weaning success was associated with male gender, younger age and slightly higher BMI. Obstructive airway disease showed significant increase in success than failure (25.2% vs 11.7% respectively). Weaning failure was significantly associated increased septic shock and pneumonia. The muscle thickness in inspiration was significantly increased in success than failure (25.56 vs 24.08 respectively). DE before weaning was the most sensitive indicator at cut-off value &gt; 15 followed by DE after weaning at cutoff value &gt;17; while DTF after weaning was more sensitive than DTF before weaning (93.55% and 80.65% respectively) at cutoff points &gt; 20.4 and &gt; 18.5, respectively.&#x0D; Conclusion: Assessment of DTF and DE by diaphragm ultrasound is an easy to obtain new weaning index that can be a bedside method in clinical practice with promising predictors of weaning success or failure before and after weaning.