Hours Of Ventilation Research Articles

Impact of under-assisted ventilation on diaphragm function and structure in a porcine model.

Long-term controlled mechanical ventilation (CMV) in intensive care unit (ICU) induces ventilatory-induced-diaphragm-dysfunction (VIDD). The transition from CMV to assisted mechanical ventilation is a challenge that requires clinicians to balance over-assistance and under-assistance. While the effects of over-assistance on the diaphragm are well known, we aimed to assess the impact of under-assistance on diaphragm function and structure in piglet model with pre-existing VIDD (after long-term CMV) or without VIDD (short-term CMV). Twenty-two Large-White female piglets were anesthetized, ventilated, and separated into two groups: a VIDD group (n=10) with long-term 72-hour CMV, and a no-VIDD group (n=12) with short-term 2-hour CMV. After sedation reduction at the end of CMV period, each piglet was switched to under-assisted ventilation for 2 hours. Diaphragm function (supramaximal diaphragm pressure-generating capacity assessed by negative tracheal pressure after transvenous phrenic nerve stimulation) and diaphragm structure (mini-invasive in vivo biopsies) were assessed before and after under-assisted ventilation. In VIDD group, supramaximal diaphragm pressure-generating capacity decreased by 22% from 69.9±12.7 to 54.9±19.7 cmH2O (p=0.04) after 72 hours of CMV evidencing VIDD, then dropped by a further 29% from 54.9±19.7 to 38.9±15.5 cmH2O (p<0.01) after 2 hours of under-assisted ventilation. Diaphragm pressure-generating capacity remains stable from 55.3±22.7 to 58.2±24 cmH2O (p=0.24) in no-VIDD group. Diaphragm structure showed sarcomeric injuries increase from 13±10% to 24±19% (p<0.01) and lipid droplets decrease from 14±8% to 11±6% (p=0.03) of the total micrograph area after 2 hours of under-assisted ventilation in the VIDD group. Sarcomeric injuries and lipid droplets accounted respectively for 17±16% and 2±3% of the total micrograph area after under-assisted ventilation in the no-VIDD group. In this porcine model, a short two-hour exposure of under-assisted ventilation induces impairment of diaphragm function with damage to the diaphragm structure in ICU condition with pre-existing VIDD.

A high fraction of inspired oxygen does not mitigate atelectasis-induced lung tissue hypoxia or injury in experimental acute respiratory distress syndrome

Although alveolar hyperoxia exacerbates lung injury, clinical studies have failed to demonstrate the beneficial effects of lowering the fraction of inspired oxygen (FIO2) in patients with acute respiratory distress syndrome (ARDS). Atelectasis, which is commonly observed in ARDS, not only leads to hypoxemia but also contributes to lung injury through hypoxia-induced alveolar tissue inflammation. Therefore, it is possible that excessively low FIO2 may enhance hypoxia-induced inflammation in atelectasis, and raising FIO2 to an appropriate level may be a reasonable strategy for its mitigation. In this study, we investigated the effects of different FIO2 levels on alveolar tissue hypoxia and injury in a mechanically ventilated rat model of experimental ARDS with atelectasis. Rats were intratracheally injected with lipopolysaccharide (LPS) to establish an ARDS model. They were allocated to the low, moderate, and high FIO2 groups with FIO2 of 30, 60, and 100%, respectively, a day after LPS injection. All groups were mechanically ventilated with an 8 mL/kg tidal volume and zero end-expiratory pressure to induce dorsal atelectatic regions. Arterial blood gas analysis was performed every 2 h. After six hours of mechanical ventilation, the rats were euthanized, and blood, bronchoalveolar lavage fluid, and lung tissues were collected and analyzed. Another set of animals was used for pimonidazole staining of the lung tissues to detect the hypoxic region. Lung mechanics, ratios of partial pressure of arterial oxygen (PaO2) to FIO2, and partial pressure of arterial carbon dioxide were not significantly different among the three groups, although PaO2 changed with FIO2. The dorsal lung tissues were positively stained with pimonidazole regardless of FIO2, and the HIF-1α concentrations were not significantly different among the three groups, indicating that raising FIO2 could not rescue alveolar tissue hypoxia. Moreover, changes in FIO2 did not significantly affect lung injury or inflammation. In contrast, hypoxemia observed in the low FIO2 group caused injury to organs other than the lungs. Raising FIO2 levels did not attenuate tissue hypoxia, inflammation, or injury in the atelectatic lung region in experimental ARDS. Our results indicate that raising FIO2 levels to attenuate atelectasis-induced lung injury cannot be rationalized.

The effect of an additional pre-extubational loading dose of caffeine citrate on mechanically ventilated preterm infants (NEOKOFF trial): Study protocol for a multicenter randomized clinical trial.

Minimizing the duration of mechanical ventilation is one of the most important therapeutic goals during the care of preterm infants at neonatal intensive care units (NICUs). The rate of extubation failure among preterm infants is between 16% and 40% worldwide. Numerous studies have been conducted on the assessment of extubation suitability, the optimal choice of respiratory support around extubation, and the effectiveness of medical interventions. Since the Caffeine Therapy for Apnea of Prematurity (CAP) trial, caffeine has become one of the essential drugs at NICUs. However, the optimal dosage and timing for adequate effectiveness still need to be more conclusive. Previous studies suggest that higher doses of caffeine treatment increase the success rate of extubation. Therefore, we aim to determine whether using a single additional loading dose of caffeine citrate one hour prior to extubation impacts the success rate of extubation. The study is an open-label, multicenter randomized clinical trial testing the effectiveness and safety of pre-extubational loading dose of caffeine citrate. Inclusion criteria will be infants born before the 32nd gestational week, before the first extubation attempt after at least 48 hours of mechanical ventilation, and a signed parental informed consent. A total of 226 patients will be randomly allocated to either the experimental or control group. The randomization will be stratified by gestational age and antenatal steroid prophylaxis. Preterm infants in the experimental group will receive an additional intravenous (IV) loading dose (20 mg/kg) of caffeine citrate one hour before the first planned extubation, in addition to the standard dosing regimen (20 mg/kg caffeine citrate IV on the first day of life and 5 to 10 mg/kg IV or orally caffeine citrate each consecutive day). Preterm infants in the control group will receive the standard dosing regimen. The primary outcome will be reintubation within 48 hours. A pre-extubational loading dose of caffeine citrate can reduce extubation failure. Obtaining evidence on this feature has the potential to contribute to finding the optimal dosing regimen. The study protocol was approved by the Hungarian Ethics Committee for Clinical Pharmacology of the Medical Research Council and National Institute of Pharmacy and Nutrition (OGYÉI/6838-11/2023). ClinicalTrials.gov identifier NCT06401083 Registered 06. May 2024.; EudraCT number: 2022-003202-77.

Extreme nutritional neglect leading to cardiac arrest in a child: a rare presentation of severe acute malnutrition in England

This case report from England describes an 8-year-old girl who suffered severe health complications culminating in cardiac arrest due to profound neglect and malnutrition. The patient presented with cardiac arrest, which was attributed to her severe wasting. Upon admission, her body mass index measured 12.8 kg/m2 (z-score ranging between -2 and -3), indicative of severe malnutrition. The patient presented with respiratory, renal, and hepatic failure, in addition to disseminated intravascular coagulation. Resuscitative measures were administered, and she underwent 162 hours of ventilation in the paediatric intensive care unit. Despite the gravity of her initial presentation, the patient exhibited a notable recovery. Paediatric cardiac arrest stemming from extreme nutritional neglect is a rare occurrence in England. This case underscores the paramount importance of prompt intervention and comprehensive medical oversight. The patient's relatively favourable recovery underscores the potential for positive outcomes when timely and appropriate medical interventions are employed.

Risk Factors for ARDS in Hospitalized Burn Patients: An Analysis of the National Trauma Data Bank.

Acute Respiratory Distress Syndrome (ARDS) is a common complication among mechanically ventilated adult burn patients; however, the risk factors associated with its development are not well understood. Conflicting evidence also exists regarding ARDS as an independent predictor of poor hospital outcomes. The purpose of this study is to identify risk factors for ARDS in mechanically ventilated adult burn patients and characterize the impact of ARDS on hospital course. The National Trauma Data Bank (NTDB) was queried for patients >=18 years with International Classification of Diseases (ICD) codes corresponding to burn injury from 2007-2016. Hospitalized patients with at least 48 hours of mechanical ventilation were included. Multivariate logistic regression were used to identify risk factors for ARDS. Propensity score-matched analysis at a 1:3 ratio was used to determine the impact of ARDS on hospital course. This sample included 13928 patients, of which 1437 (10.3%) developed ARDS. Hypotension in the Emergency Department, alcohol use disorder, total body surface area (TBSA), Injury Severity Score (ISS), and inhalation injury were independently associated with ARDS. In the propensity score-matched cohort, ARDS patients had a significantly longer median (interquartile range) length of stay (31 [15-54] vs. 22 [9-43], p<0.001). In-hospital mortality was also significantly higher in the ARDS cohort (203 [35%] vs. 325 [24%], p<0.001). These findings highlight the impact of patient and injury characteristics on developing ARDS and support the consideration of ARDS when estimating mortality risk in burn patients.

Bilateral multiple ribs and sternum fracture causing central flail chest with respiratory failure

Bilateral thoracic blunt injuries in a patient may present with central Flail chest, and acute respiratory failure which is one of the life-threatening complications. We present a case of central flail chest caused by blunt trauma, successfully managed with operative rib and sternum fixation. A 35-year male with a central flail chest with acute respiratory failure caused by road-traffic accident who was managed initially with bilateral intercostal chest-tube drainage for significant bilateral hemopneumothorax and lung contusions. The patient was intubated and connected to mechanical ventilatory support with positive pressure ventilation for the internal pneumatic stabilization. There were multiple rib fractures anteriorly (first to seventh rib bilaterally) and fracture of the sternum - the flail chest, for which he underwent bilateral rib fixation and fixation of sternum with titanium reconstruction plate and screws on the 9th postinjury day. Tracheostomy was done along with fixation in the same sitting. Post-operatively, after 48 hours of positive pressure mechanical ventilation, the weaning was started and by the 4-5th day, the patient was on room air with a tracheostomy tube. The patient recovered uneventfully and was discharged on the eighth postoperative day.

Risk Factors for Increased Opioid Use During Postoperative Intensive Care.

In the ICU, opioids treat pain and improve ventilator tolerance as part of an analgosedation approach. Identifying predictors of opioid consumption during the ICU course might highlight actionable items to reduce opioid consumption. To identify risk factors for opioid use during a postoperative ICU course. Patients enrolled in the Michigan Genomics Initiative single-center prospective observational cohort study completed baseline preoperative sociodemographic and mental/physical health questionnaires and provided blood samples for genetic analysis. Included patients were 18 years old and older, admitted to ICU postoperatively, and received opioids postoperatively. The primary outcome was ICU mean daily oral morphine equivalent (OME) use. The association between OME and phenotypic risk factors and genetic variants previously associated with pain were analyzed through univariable and multivariable linear regression models. The cohort consisted of 1865 mixed-surgical patients with mean age of 56 years (sd, 15 yr). Preoperative opioid users were more likely to continue to receive opioids throughout their ICU stay than opioid-naive patients. OME (log10 scale) was most strongly associated with ICU mechanical ventilation (β = 0.27; 95% CI, 0.15-0.38; p < 0.0001; effect size 1.85 for receiving > 24 hours of mechanical ventilation), preoperative opioid use (β = 0.22; 95% CI, 0.16-0.29; p < 0.0001; effect size 1.67 for receiving preoperative opioids), major surgery (β = 0.21; 95% CI, 0.12-0.30; p < 0.0001; effect size 1.62 compared with minor surgery), and current/former illicit drug use (β = 0.12; 95% CI, 0.01-0.23; p = 0.04; effect size 1.30 for drug use). Younger age, centralized pain, and longer anesthetic duration were also significantly associated with OME but with smaller effect sizes. Selected genetic variants (FKBP5, COMT, and OPRM1) were not associated with OME use. Mechanical ventilation and preoperative opioids were the strongest risk factors for postoperative ICU opioid consumption, whereas psychologic factors and genetic variants were not associated.

Impact of mechanical power on ICU mortality in ventilated critically ill patients: a retrospective study with continuous real-life data

BackgroundOver the past decade, numerous studies on potential factors contributing to ventilation-induced lung injury have been carried out. Mechanical power has been pointed out as the parameter that encloses all ventilation-induced lung injury-contributing factors. However, studies conducted to date provide data regarding mechanical power during the early hours of mechanical ventilation that may not accurately reflect the impact of power throughout the period of mechanical ventilatory support on intensive care unit mortality.MethodsRetrospective observational study conducted at a single center in Spain. Patients admitted to the intensive care unit, > o = 18 years of age, and ventilated for over 24 h were included. We extracted the mechanical power values throughout the entire mechanical ventilation in controlled modes period from the clinical information system every 2 min. First, we calculate the cutoff-point for mechanical power beyond which there was a greater change in the probability of death. After, the sum of time values above the safe cut-off point was calculated to obtain the value in hours. We analyzed if the number of hours the patient was under ventilation with a mechanical power above the safe threshold was associated with intensive care unit mortality, invasive mechanical ventilation days, and intensive care unit length of stay. We repeated the analysis in different subgroups based on the degree of hypoxemia and in patients with SARS CoV-2 pneumonia.ResultsThe cut-off point of mechanical power at with there is a higher increase in intensive care unit mortality was 18 J/min. The greater the number of hours patients were under mechanical power > 18 J/min the higher the intensive care unit mortality in all the study population, in patients with SARS CoV-2 pneumonia and in mild to moderate hypoxemic respiratory failure. The risk of death in the intensive care unit increases 0.1% for each hour with mechanical power exceeding 18 J/min. The number of hours with mechanical power > 18 J/min also affected the days of invasive mechanical ventilation and intensive care unit length of stay.ConclusionsThe number of hours with mechanical power > 18 J/min is associated with mortality in the intensive care unit in critically ill patients. Continuous monitoring of mechanical power in controlled modes using an automated clinical information system could alert the clinician to this risk.

Association between PaO2/(FiO2*PEEP) ratio and in-hospital mortality in COVID-19 patients: A reanalysis of published data from Peru using PaO2/(FiO2*PEEP) ratio in place of PaO2/FaO2 ratio.

P/FP [PaO2/(FiO2*PEEP)] is associated with in-hospital mortality in patients with acute respiratory distress syndrome (ARDS). However, to the best of our knowledge, the association between P/FP after 24 hours of invasive mechanical ventilation (IMV) and in-hospital mortality in patients with ARDS due to Coronavirus Disease 2019 (COVID-19) remained unclear. This study aimed to evaluate the relationship between the P/FP after 24 hours of IMV and in-hospital mortality in patients with ARDS due to COVID-19. We reanalyzed previously published data from Peru. Hueda-Zavaleta et al conducted a retrospective cohort study between April 2020 and April 2021 in southern Peru. A total of 200 hospitalized COVID-19 patients requiring IMV were included in this analysis. We used Cox proportional hazard regression models and Kaplan-Meier survival analysis to investigate the effect of P/FP after 24 hours of IMV on in-hospital mortality. We used a restricted cubic spline regression and a two-piecewise Cox proportional hazards model to explore the relationship between P/FP after 24 hours of IMV and in-hospital mortality in patients with ARDS due to COVID-19. Of the 200 patients, 51 (25.50%) died in hospital. The median P/FP was 20.45 mm Hg/cmH2O [interquartile range 15.79-25.21 mm Hg/cmH2O], with a range of 5.67 mm Hg/cmH2O to 51.21 mm Hg/cmH2O. Based on the P/FP ratio, patients were equally divided into 2 groups (low group [P/FP < 20.50 mm Hg/cmH2O] and high group [P/FP ≥ 20.50 mm Hg/cmH2O]). In-hospital mortality was lower in the high P/FP group than in the low P/FP group (12 [12%] vs 39 [39%]; unadjusted hazard ratio [HR]: 0.33, 95% confidence interval [CI]: 0.17-0.63; adjusted HR: 0.10, 95% CI: 0.02-0.47). We also found a nonlinear relationship between P/FP and in-hospital mortality. After adjusting for potential confounders, the HR was 0.67 (95% CI: 0.56-0.79) for P/FP ≤ 22 mm Hg/cmH2O and 1.10 (95% CI: 0.83-1.47) for P/FP > 22 mm Hg/cmH2O. In addition, lymphocytes ≤ 1 × 109/L and acute kidney failure had a higher risk of death. After adjusting for potential confounders, the P/FP after 24 hours of IMV was nonlinearly associated with in-hospital mortality in patients with ARDS due to COVID-19.

Extended versus Standard Proning Duration for COVID-19-associated Acute Respiratory Distress Syndrome: A Target Trial Emulation Study.

Rationale: Prone positioning for ⩾16 hours in moderate-to-severe acute respiratory distress syndrome (ARDS) improves survival. However, the optimal duration of proning is unknown. Objectives: To estimate the effect of extended versus standard proning duration on patients with moderate-to-severe coronavirus disease (COVID-19) ARDS. Methods: Data were extracted from a five-hospital electronic medical record registry. Patients who were proned within 72 hours of mechanical ventilation were categorized as receiving extended (⩾24 h) versus standard (16-24 h) proning based on the first proning session length. We used a target trial emulation design to estimate the effect of extended versus standard proning on the primary outcome of 90-day mortality and secondary outcomes of ventilator liberation and intensive care unit (ICU) discharge. Analytically, we used inverse probability of treatment weighted (IPTW) Cox or Fine-Gray regression models. Results: A total of 314 patients were included; 234 received extended proning, and 80 received standard-duration proning. Patients who received extended proning were older, had greater comorbidity, were more often at an academic hospital, and had shorter time from admission to mechanical ventilation. After IPTW, characteristics were well balanced. Unadjusted 90-day mortality in the extended versus standard proning groups was 39% versus 58%. In doubly robust IPTW analyses, we found no significant effects of extended versus standard proning duration on mortality (hazard ratio [95% confidence interval], 0.95 [0.51-1.77]), ventilator liberation (subdistribution hazard, 1.60 [0.97-2.64], or ICU discharge (subdistribution hazard, 1.31 [0.82-2.10]). Conclusions: Using target trial emulation, we found no significant effect of extended versus standard proning duration on mortality, ventilator liberation, or ICU discharge. However, given the imprecision of estimates, further study is justified.

A Retrospective Multicenter Study of Operating Room Extubation and Extubation Timing following Cardiac Surgery

BackgroundIn an effort to enhance recovery after cardiac surgery, intraoperative extubation has been targeted as possibly beneficial. This multi-center cohort study aimed to assess this by evaluating the outcomes of OR extubation versus extubation within six hours of intensive care unit arrival (early ICU extubation). Furthermore, we assessed time to ICU extubation and mortality and morbidity. MethodsPatients undergoing on-pump cardiac surgery across 79 hospitals between 2011-2020 were included to 1) compare outcomes among OR extubation and early ICU extubation patients, and 2) assess time to overall ICU extubation and outcomes. ResultsThe overall study cohort comprised 163,982 patients, including 95,982 patients [ [ OR extubation : n= 2,529 (2.6%)and early ICU extubation : n= 93,453 (97.4%)] who underwent comparison of OR with early ICU extubation. Following overlap weighting, OR extubation patients had longer OR times (5.6 vs. 5.1 hours, p < 0.0001), and higher rates of reintubation (5.2% vs 2.9%, p=0.003), prolonged ventilation (3% vs 2%, p = 0.021), reoperation for bleeding (1.5% vs 0.7%, p < 0,01), pneumonia (1.9% vs. 1.1% , p < 0.006), and greater in-hospital mortality on multivariable regression (OR 1.34, p < 0.001). OR extubation patients at centers with low OR extubation rates (< 10%, N=60) had higher mortality (odds ratio 1.6, p = 0.001). Beyond 22 hours of postoperative ICU ventilation, the risk of morbidity and mortality increased significantly . ConclusionsFew cardiac surgery patients are extubated in the OR, which is associated with no clinical benefit and with increased morbidity. Cardiac surgery programs should reconsider OR extubation following cardiopulmonary bypass. Additionally, increased intubation time, in particular > 22 hours, is associated with an increase in adverse outcomes.

Outcomes Following Neonatal Cardiac Surgery in Cape Town, South Africa.

Neonatal Cardiac Surgery has developed significantly since its advent, with improved outcomes, survival, and physiological repair. Limited programs offer neonatal cardiac surgery in emerging economies. We report our experience with neonates undergoing cardiac surgery in our cardiac surgery program. We performed a secondary data analysis on all neonates aged ≤ 30 days undergoing congenital cardiac surgery from April 1, 2017 to March 31, 2020, including outcomes up to 30-days post-surgery. A total of 859 patients underwent cardiac surgery at our center, of these 81 (9.4%) were neonates. The proportion of neonates increased annually (8.7%, 9.6%, and 10.2%). There were 49 (60%) male patients, and 32 (40%) had surgery in the second week of life. Fourteen (17%) were premature, four (5%) had a major chromosomal abnormality, five (6%) a major medical illness, and eight (10%) a major noncardiac structural anomaly. The Risk Adjustment for Congenital Heart Surgery (RACHS) categorization of surgery was predominantly RACHS 3; n = 28 (35%) and 4; n = 23 (29%). Hours in the intensive care unit (ICU) were extensive; median 189 [interquartile range (IQR): 114-286] as were hours of ventilation; median 95 [IQR 45-163]. Almost 60% (n = 48) of procedures were complicated by sepsis, as defined in our database. The in-hospital mortality rate was 16% (n = 13); the 30-day mortality rate was 19.8% (n = 16). The proportion of neonates in our service increased over the period. Focused strategies to shorten prolonged ICU stay and decrease rates of bacterial sepsis in neonates are needed. A multidisciplinary, collaborative heart-team approach is crucial for best outcomes.

Association of Acute Systemic Inflammation with Patient-Centric Postoperative Pulmonary Complications After Elective Cardiac Surgery.

Postoperative pulmonary complications (PPCs) occur frequently after cardiac surgery. Absolute postoperative values of biomarkers of inflammation (interleukin [IL]-6, IL-8, and tumor necrosis factor-alpha [TNF-α]) and alveolar epithelial injury (soluble receptor for advanced glycation end-products [sRAGE]) have been associated with hypoxia and prolonged ventilation. However, relationships between these biomarkers and PPCs, contextualized to preoperative inflammation and perioperative lung injury risk factors, are uncertain. We aimed to determine associations between perioperative increases in biomarkers of inflammation and alveolar epithelial injury with a patient-centric PPC definition in adult cardiac surgical patients, accounting for the influence of intraoperative risk factors for lung injury. Adults undergoing elective cardiac surgery were eligible for this observational cohort study. Blood concentrations of IL-6, IL-8, TNF-α, and sRAGE were collected after anesthesia induction (baseline) and on postoperative day 1 (POD 1). The primary outcome was the occurrence of moderate or severe PPCs, graded using a validated scale, in POD 0 to 7. We estimated the association between POD 1 IL-6, IL-8, TNF-α, and sRAGE concentrations and moderate/severe PPC presence using separate logistic regression models for each biomarker, adjusted for baseline biomarker values and risk factors for postoperative lung injury (age, baseline PaO2/FiO2, left ventricle ejection fraction [LVEF], procedural type, cardiopulmonary bypass duration, and transfusions). Covariables were chosen based on relevance to lung injury and unadjusted between-group differences among patients with versus without PPCs. The secondary outcome was postoperative ventilation duration, which was log-transformed and analyzed using linear regression, adjusted using the same variables as the primary outcome. We enrolled 204 patients from 2016 to 2018. Biomarkers were analyzed in 2023 among 175 patients with complete data. In adjusted analyses, POD 1 IL-8 and IL-6 were significantly associated with moderate/severe PPCs. The odds ratio (OR) for developing a PPC for every 50 pg/mL increase in POD 1 IL-8 was 7.19 (95% confidence interval [CI], 2.13-28.53, P = .003) and 1.42 (95% CI, 1.13-1.93, P = .01) for every 50 pg/mL increase in POD 1 IL-6. In adjusted analyses, postoperative ventilation duration was significantly associated with POD 1 sRAGE; each 50 pg/mL increase in sRAGE was associated with a 25% (95% CI, 2%-52%, P = .03) multiplicative increase in hours of ventilation. TNF-α was not significantly associated with PPCs or ventilation duration. Acute systemic inflammation is significantly associated with PPCs after elective cardiac surgery in adults when taking into consideration preoperative inflammatory burden and perioperative factors that may influence postoperative lung injury.

Lung Protective Ventilation Adherence and Outcomes for Patients With COVID-19 Acute Respiratory Distress Syndrome Treated in an Intermediate Care Unit Repurposed to ICU Level of Care.

During the COVID-19 pandemic, some centers converted intermediate care units (IMCUs) to COVID-19 ICUs (IMCU/ICUs). In this study, we compared adherence to lung protective ventilation (LPV) and outcomes for patients with COVID-19-related acute respiratory distress syndrome (ARDS) treated in an IMCU/ICU versus preexisting medical ICUs (MICUs). Retrospective observational study using electronic medical record data. Two academic medical centers from March 2020 to September 2020 (period 1) and October 2020 to May 2021 (period 2), which capture the first two COVID-19 surges in this health system. Adults with COVID-19 receiving invasive mechanical ventilation who met ARDS oxygenation criteria (Pao2/Fio2 ≤ 300 mm Hg or Spo2/Fio2 ≤ 315). None. We defined LPV adherence as the percent of the first 48 hours of mechanical ventilation that met a restrictive definition of LPV of, tidal volume/predicted body weight (Vt/PBW) less than or equal to 6.5 mL/kg and plateau pressure (Pplat) less than or equal to 30 cm H2o. In an expanded definition, we added that if Pplat is greater than 30 cm H2o, Vt/PBW had to be less than 6.0 mL/kg. Using the restricted definition, period 1 adherence was lower among 133 IMCU/ICU versus 199 MICU patients (92% [95% CI, 50-100] vs. 100% [86-100], p = 0.05). Period 2 adherence was similar between groups (100% [75-100] vs. 95% CI [65-100], p = 0.68). A similar pattern was observed using the expanded definition. For the full study period, the adjusted hazard of death at 90 days was lower in IMCU/ICU versus MICU patients (hazard ratio [HR] 0.73 [95% CI, 0.55-0.99]), whereas ventilator liberation by day 28 was similar between groups (adjusted subdistribution HR 1.09 [95% CI, 0.85-1.39]). In patients with COVID-19 ARDS treated in an IMCU/ICU, LPV adherence was similar to, and observed survival better than those treated in preexisting MICUs. With adequate resources, protocols, and staffing, IMCUs provide an effective source of additional ICU capacity for patients with acute respiratory failure.

Preoperative right ventricular strain as an early predictor of perioperative cardiac failure in patients undergoing mitral surgery: An exploratory study.

This study's primary purpose was to demonstrate the correlation of preoperative right ventricular free-wall longitudinal strain (RVFWLS) and pre-/postsurgical variation in strain (delta strain) with the clinical and echocardiographic diagnosis of right ventricular dysfunction. Its secondary purpose was to determine the correlation of RVFWLS and delta strain with length of stay (LOS) in the intensive care unit (ICU), ventilation days, trend of natriuretic peptide test. (NT-proBNP) and lactate in the first 48 h, incidence of acute renal failure, and 28-day mortality. Prospective observational study. Cardio-thoracic and Vascular Anaesthesia Department and ICU of the University Hospital Integrated Trust of Verona. Patients scheduled for mitral surgery. None. All clinical and transoesophageal echocardiographic (TEE) parameters were collected at baseline, before surgery (T1) and at admission in the ICU postsurgery (T2). During the postoperative period, the clinical and echocardiographic diagnoses of right, left, or biventricular dysfunction were evaluated. TEE parameters were evaluated by a cardiologist offline. The patients were divided into two subgroups according to the development of any type of ventricular dysfunction. No statistically significant differences emerged between the two groups. According to a logistic regression model, a T1-RVFWLS value of -15% appeared to predict biventricular dysfunction (sensitivity: 100%; specificity: 91.3%). No correlation between T1- or T2-RVFWLS and creatinine, hours of ventilation or ICU LOS was found. Our study introduces a new parameter that could be used in perioperative evaluations to identify patients at risk of postoperative biventricular dysfunction.

Differential Effects of Intra-Abdominal Hypertension and ARDS on Respiratory Mechanics in a Porcine Model.

Background and Objectives: Intra-abdominal hypertension (IAH) and acute respiratory distress syndrome (ARDS) are common concerns in intensive care unit patients with acute respiratory failure (ARF). Although both conditions lead to impairment of global respiratory parameters, their underlying mechanisms differ substantially. Therefore, a separate assessment of the different respiratory compartments should reveal differences in respiratory mechanics. Materials and Methods: We prospectively investigated alterations in lung and chest wall mechanics in 18 mechanically ventilated pigs exposed to varying levels of intra-abdominal pressures (IAP) and ARDS. The animals were divided into three groups: group A (IAP 10 mmHg, no ARDS), B (IAP 20 mmHg, no ARDS), and C (IAP 10 mmHg, with ARDS). Following induction of IAP (by inflating an intra-abdominal balloon) and ARDS (by saline lung lavage and injurious ventilation), respiratory mechanics were monitored for six hours. Statistical analysis was performed using one-way ANOVA to compare the alterations within each group. Results: After six hours of ventilation, end-expiratory lung volume (EELV) decreased across all groups, while airway and thoracic pressures increased. Significant differences were noted between group (B) and (C) regarding alterations in transpulmonary pressure (TPP) (2.7 ± 0.6 vs. 11.3 ± 2.1 cmH2O, p < 0.001), elastance of the lung (EL) (8.9 ± 1.9 vs. 29.9 ± 5.9 cmH2O/mL, p = 0.003), and elastance of the chest wall (ECW) (32.8 ± 3.2 vs. 4.4 ± 1.8 cmH2O/mL, p < 0.001). However, global respiratory parameters such as EELV/kg bodyweight (-6.1 ± 1.3 vs. -11.0 ± 2.5 mL/kg), driving pressure (12.5 ± 0.9 vs. 13.2 ± 2.3 cmH2O), and compliance of the respiratory system (-21.7 ± 2.8 vs. -19.5 ± 3.4 mL/cmH2O) did not show significant differences among the groups. Conclusions: Separate measurements of lung and chest wall mechanics in pigs with IAH or ARDS reveals significant differences in TPP, EL, and ECW, whereas global respiratory parameters do not differ significantly. Therefore, assessing the compartments of the respiratory system separately could aid in identifying the underlying cause of ARF.

COMPLICATIONS OF USING A DOUBLE-LUMEN ENDOTRACHEAL TUBE AND THEIR TREATMENT

A 46-year-old woman, withheight 161 cm and weight 75 kg, underwent endoscopic resection of the esophagus with reconstruction of the gastrointestinal tract with a gastric tube (McKeown procedure). During the surgery a tracheal injury with a rupture of the membranous part revealed, which was considered as a complication regarding a double-lumen endotracheal tube installation. Clinically, the rupture remained asymptomatic during two hours of single-lung ventilation of the left lung and was visualized during the thoracoscopic stage of the surgery. The tracheal rupture was promptly repaired. In the postoperative period, the patient required prolonged lung ventilation through a laryngeal mask. Frequentbronchial fibroscopy was performed to verify the condition of the tracheal suture, its continuity, and to provide tracheobronchial sanitation in the intensive care unit. The application of a multidisciplinary approach to diagnose and treat a life-threatening complication as tracheal rupture in a short time allowed us to stabilize the patient’s condition and avoid the development of further complications.

Effects of helium-oxygen mechanical ventilation on inflammatory response of diseased lung segments and diaphragm function in patients with pneumonia

To investigate the clinical effect of helium-oxygen mechanical ventilation on inflammation of the diseased lung segment and diaphragm function in patients with acute respiratory distress syndrome (ARDS) caused by pneumonia who suffered difficulty weaning from mechanical ventilation. A prospective controlled study was conducted. A total of 40 patients with ARDS caused by pneumonia and requiring tracheal intubation with difficulty weaning from mechanical ventilation, admitted to the department of critical care medicine in Pingtan Branch of Fujian Medical University Union Hospital from October 2020 to December 2021 were enrolled. Patients were divided into nitrogen oxygen ventilation group and helium-oxygen ventilation group according to random number table, with 20 cases in each group. The nitrogen oxygen ventilation group was given 60% nitrogen and 40% oxygen ventilation treatment, and the helium-oxygen ventilation group was given 60% helium and 40% oxygen ventilation treatment. Peak airway pressure (Ppeak), plateau airway pressure (Pplat), tidal volume (VT), minute ventilation volume (MV) and pulse oxygen saturation (SpO2) were collected at 0, 1, 2, 3 hours after ventilation treatment. At the same time, the concentrations of inflammatory factors interleukin-6 (IL-6) and C-reactive protein (CRP) in epithelial lining fluid in patients with diseased lung segments were measured before and after ventilation treatment for 3 hours, and the diaphragmatic excursion and the diaphragmatic thickening fraction were measured before and after ventilation treatment for 3 hours. There were no significant differences in gender, age, oxygenation index, serum CRP, serum procalcitonin (PCT), body temperature, serum creatinine (SCr), alanine aminotransferase (ALT), fasting blood glucose (FPG), hemoglobin (Hb), and basic heart and lung diseases between the two groups. Under the condition that VT and SpO2 are relatively unchanged, the airway pressure in helium-oxygen ventilation group decreased significantly after 1 hour of ventilation [Ppeak (cmH2O, 1 cmH2O≈0.098 kPa): 22.80±4.47 vs. 28.00±5.07, Pplat (cmH2O): 19.15±3.90 vs. 23.20±3.81, both P < 0.05], and the airway pressure in the nitrogen oxygen ventilation group increased significantly after 1 hour [Ppeak (cmH2O): 22.35±2.13 vs. 19.75±1.94, Pplat (cmH2O): 18.50±1.70 vs. 16.50±1.88, both P < 0.05]. There were no significant differences in CRP and IL-6 levels in epithelial lining fluid in the diseased lung segment before and after ventilation in the nitrogen oxygen ventilation group, while the levels of these indexes in the helium-oxygen ventilation group after ventilation were significantly lower than those before ventilation, and significantly lower than those in the nitrogen oxygen ventilation group [CRP (mg/L): 10.15 (6.39, 15.84) vs. 16.10 (11.63, 18.66), IL-6 (μg/L): 1.15 (0.78, 1.86) vs. 2.67 (1.67, 4.85), both P < 0.05]. There were no statistically significant differences in the diaphragmatic excursion and the diaphragmatic thickening fraction before and after ventilation in the nitrogen oxygen ventilation group, while the above indexes in the helium-oxygen ventilation group were significantly higher than those before ventilation, and were significantly higher than those in the nitrogen oxygen ventilation group [diaphragmatic excursion (cm): 1.93 (1.69, 2.20) vs. 1.34 (1.22, 1.83), diaphragmatic thickening fraction: (48.22±8.61)% vs. (33.29±11.04)%, both P < 0.05]. Helium-oxygen ventilation can reduce the airway pressure of patients with mechanical ventilation, alleviate the inflammatory response of lung segment, improve the function of respiratory muscle, and is expected to be an important treatment for severe lung rehabilitation.

Iron Deficiency in Anemic Children Surviving Critical Illness: Post Hoc Analysis of a Single-Center Prospective Cohort in Canada, 2019-2022.

Many children leave the PICU with anemia. The mechanisms of post-PICU anemia are poorly investigated, and treatment of anemia, other than blood, is rarely started during PICU. We aimed to characterize the contributions of iron depletion (ID) and/or inflammation in the development of post-PICU anemia and to explore the utility of hepcidin (a novel iron marker) at detecting ID during inflammation. Post hoc analysis of a single-center prospective study (November 2019 to September 2022). PICU, quaternary center, Canada. Children admitted to PICU with greater than or equal to 48 hours of invasive or greater than or equal to 96 hours of noninvasive ventilation. We excluded patients with preexisting conditions causing anemia or those admitted after cardiac surgery. None. Hematological and iron profiles were performed at PICU discharge on 56 participants of which 37 (37/56) were diagnosed with anemia. Thirty-three children (33/56; 59%) were younger than 2 years. Median Pediatric Logistic Organ Dysfunction score was 11 (interquartile range, 6-16). Twenty-four of the 37 anemic patients had repeat bloodwork 2 months post-PICU. Of those, four (4/24; 16%) remained anemic. Hematologic profiles were categorized as: anemia of inflammation (AI), iron deficiency anemia (IDA), IDA with inflammation, and ID (low iron stores without anemia). Seven (7/47; 15%) had AI at discharge, and one had persistent AI post-PICU. Three patients (3/47; 6%) had IDA at discharge; of which one was lost to follow-up and the other two were no longer anemic but had ID post-PICU. Eleven additional patients developed ID post-PICU. In the exploratory analysis, we identified a diagnostic cutoff value for ID during inflammation from the receiver operating characteristic curve for hepcidin of 31.9 pg/mL. This cutoff would increase the detection of ID at discharge from 6% to 34%. The burden of ID in children post-PICU is high and better management strategies are required. Hepcidin may increase the diagnostic yield of ID in patients with inflammation.

Is Prone Positioning Worth the Turn in Pediatrics? Unraveling the Oxygenation Mystery in Ventilated Patients with Acute Respiratory Distress Syndrome: An Observational Study Introducing a Novel SF Ratio Method for Non-Invasive Monitoring in Children

Background: Respiratory illnesses are prevalent among children, attributed to factors such as immature immune systems, anatomical variations, and increased susceptibility to infections. Acute respiratory distress syndrome (ARDS) is a significant cause of morbidity and mortality, necessitating various forms of respiratory support in pediatric intensive care units (PICUs). Prone positioning has emerged as a strategy to improve oxygenation in ARDS, but its effectiveness and correlation with non-invasive monitoring parameters remain underexplored.&#x0D; Subjects and Methods: This prospective observational study, conducted in the PICU of Dr. B.C Roy PGIPS, Kolkata, aimed to assess the impact of prone ventilation on oxygenation in children diagnosed with ARDS. The study, spanning 18 months, included 40 patients aged 3 months to 12 years requiring mechanical ventilation. Parameters such as oxygenation index (OI), oxygen saturation index (OSI), PF ratio, and SF ratio were monitored at different time points during supine and prone ventilation. Prone positioning's effectiveness was evaluated based on improvements in these parameters.&#x0D; Results: The study revealed a significant improvement in oxygenation status after four hours of prone ventilation compared to supine ventilation. Oxygenation index, OSI, SF ratio, and PF ratio showed statistically significant changes favoring prone positioning. A strong positive correlation between SF ratio and PF ratio was observed at various time points, emphasizing the potential of SF ratio as a non-invasive alternative. Responders and non-responders to prone positioning were identified based on predefined criteria, highlighting individual variability in treatment response.&#x0D; Conclusion: Prone ventilation demonstrated significant improvements in oxygenation parameters in children with ARDS. The study supports the use of non-invasive SF ratio as a reliable substitute for PF ratio, simplifying monitoring without invasive arterial sampling. This finding has implications for improving ARDS management strategies in pediatric patients, offering a less cumbersome alternative for assessing oxygenation status.