Conventional Ventilation Research Articles

VENO-VENOUS EXTRACORPOREAL MEMBRANE OXYGENATION IMPROVES OUTCOMES IN TRAUMA PATIENTS SUFFERING RESPIRATORY FAILURE.

Veno-venous extracorporeal membrane oxygenation (VV ECMO) improves hypoxemia and carbon dioxide clearance in patients with severe respiratory derangements. A greater understanding of the potential benefits of VV ECMO in trauma patients could lead to broader adoption. We hypothesize that trauma patients who receive VV ECMO have improved mortality outcomes when compared to those receiving conventional ventilator management given the rapid stabilization VV ECMO promotes. We performed a single center, propensity score matched cohort study. All trauma patients from January 1, 2014, to October 30, 2023, who were placed on VV ECMO or who would have met institutional guidelines for VV ECMO but were managed with conventional ventilator strategies were matched 1:1. The primary outcome analysis was survival at hospital discharge. Significance was defined as p < 0.05. Eighty-one trauma VV ECMO patients and 128 patients who received conventional management met criteria for inclusion. After matching, VV ECMO and conventional treatment cohort characteristics were similar in age and MOI. Matched ISS, SI, lactate levels, and frequency of TBI were also similar. Finally, respiratory parameters including pre-intervention, pH, partial pressure of carbon dioxide (PaCO2), lactate levels, and oxygen saturation were similar between matched groups. VV ECMO patients had higher survival rates at discharge when compared to the matched conventional treatment group (70% v 41%, p < 0.001). Corresponding hazard ratio for VV ECMO use was 0.31 (95%CI 0.18-0.52; p < 0.001). The odds ratio of mortality in matched trauma patients who receive VV ECMO versus conventional treatment was 0.29 (95%CI 0.14-0.58; p < 0.001). VV ECMO may represent a safe, alternative treatment approach for appropriately screened trauma patients with acute respiratory failure, however further studies are warranted.

Design and Implementation of a Computer-Controlled Hybrid Oscillatory Ventilator.

During mechanical ventilation, lung function and gas exchange in structurally heterogeneous lungs may be improved when volume oscillations at the airway opening are applied at multiple frequencies simultaneously, a technique referred to as multifrequency oscillatory ventilation (MFOV). This is in contrast to conventional high-frequency oscillatory ventilation (HFOV), for which oscillatory volumes are applied at a single frequency. In the present study, as a means of fully realizing the potential of MFOV, we designed and tested a computer-controlled hybrid oscillatory ventilator capable of generating the flows, tidal volumes, and airway pressures required for MFOV, HFOV, conventional mechanical ventilation (CMV), as well as oscillometric measurements of respiratory impedance. The device employs an iterative spectral feedback controller to generate a wide range of oscillatory waveforms. The performance of the device meets that of commercial mechanical ventilators in volume-controlled mode. Oscillatory modes of ventilation also meet design specifications in a mechanical test lung, over frequencies from 4 to 20 Hz and mean airway pressure from 5 to 30 cmH2O. In proof-of-concept experiments, the oscillatory ventilator maintained adequate gas exchange in a porcine model of acute lung injury, using combinations of conventional and oscillatory ventilation modalities. In summary, our novel device is capable of generating a wide range of conventional and oscillatory ventilation waveforms with potential to enhance gas exchange, while simultaneously providing less injurious ventilation.

Non-Invasive Ventilation with Neurally Adjusted Ventilatory Assist (NAVA) Improves Extubation Outcomes in Extremely Low-Birth-Weight Infants.

Objective: This study investigates the effectiveness of extubation from conventional mechanical ventilation using an endotracheal tube (MVET) compared to synchronized non-invasive positive-pressure ventilation (sNIPPV) using neurally adjusted ventilatory assist (NAVA) and conventional non-invasive positive-pressure ventilation (NIPPV) in extremely low-birth-weight (ELBW) infants. Methods: An institutional review board (IRB) approved this study (#12175) to conduct a single-center randomized control trial including 60 ELBW infants assigned in a one-to-one computer-generated scheme to either sNIPPV using NAVA or NIPPV. The primary outcome involved the need for reintubation, and the secondary outcome involved the assessment of moderate/severe BPD, defined as an oxygen requirement at 36 weeks, as in #NCT03613987 (clinicaltrials.gov). Results: There were 60 ELBW infants enrolled and randomized. The overall gestational age was 26 (1.5) weeks, and the birth weight was 773 (157) g [mean (SD)]. There were no statistically significant differences between the NAVA and NIPPV patient characteristics. There was a 41% extubation failure rate in the NIPPV group and 35% in the NAVA group (p = NS). The NAVA group had less moderate and severe BPD (p = 0.03), a shorter oxygen therapy duration (p = 0.002), a decreased length of stay (p = 0.03), and less need for home oxygen (0, 43%; p = 0.0004). Conclusions: This study found similar extubation failure rates among ELBW infants as in prior studies. However, the NAVA group had lower rates of moderate/severe BPD and need for oxygen at discharge, as well as shorter oxygen therapy duration and length of stay. The use of NAVA may be a reasonable alternative mode of non-invasive ventilation in the ELBW population.

Transpulmonary Pressure-Guided Mechanical Ventilation in Severe Acute Respiratory Distress Syndrome in PICU: Single-Center Retrospective Study in North India, 2018–2021

Objectives: In this study, we have reviewed the association between esophageal pressure-guided positive end-expiratory pressure (PEEP) setting and oxygenation and lung mechanics with a conventional mechanical ventilation (MV) strategy in patient with moderate to severe pediatric acute respiratory distress syndrome (PARDS). Design: Retrospective cohort, 2018–2021. Setting: Tertiary PICU. Patients: Moderate to severe PARDS patients who required MV with PEEP of greater than or equal to 8 cm H2O. Interventions: Esophageal pressure (i.e., transpulmonary pressure [PTP]) guided MV vs. not. Measurements and Main Results: We identified 26 PARDS cases who were divided into those who had been managed with PTP-guided MV (PTP group) and those managed with conventional ventilation strategy (non-PTP). Oxygenation and lung mechanics were compared between groups at baseline (0 hr) and 24, 48, and 72 hours of MV. There were 13 patients in each group in the first 24 hours. At 48 and 72 hours, there were 11 in PTP group and 12 in non-PTP group. On comparing these groups, first, use of PTP monitoring was associated with higher median (interquartile range) mean airway pressure at 24 hours (18 hr [18–20 hr] vs. 15 hr [13–18 hr]; p = 0.01) and 48 hours (19 hr [17–19 hr] vs. 15 hr [13–17 hr]; p = 0.01). Second, use of PTP was associated with higher PEEP at 24, 48, and 72 hours (all p &lt; 0.05). Third, use of PTP was associated with lower Fio 2 and greater Pao 2 to Fio 2 ratio at 72 hours. Last, there were 18 of 26 survivors, and we failed to identify an association between use of PTP monitoring and survival. Conclusions: In this cohort of moderate to severe PARDS cases undergoing MV with PEEP greater than or equal to 8 cm H2O, we have identified some favorable associations of oxygenation status when PTP-guided MV was used vs. not. Larger studies are required.

Justification of the possibility of using liquid artificial lung ventilation for the treatment of acute respiratory distress syndrome of toxic genesis

Introduction. Pulmonotoxicants are chemicals that cause bronchospasm and damage to the alveolar capillary membrane. Lesions of the respiratory system with pulmonotoxicants in industrial accidents are especially relevant at the present time. Existing methods of treatment for the defeat of pulmonotoxicants and the development of acute respiratory distress syndrome (ARDS) are becoming ineffective, therefore, one of the tasks of modern medicine is to develop new methods of treating ARDS. One of these methods may be the creation of a "therapeutic window" by using perfluorocarbon (PFC) liquids. This article will present an experimental assessment of the use of liquid artificial lung ventilation (LALV) PFC liquids on the ARDS lung model. The study aims to explore the possibility of using liquid artificial lung ventilation to create a therapeutic window in the treatment of acute respiratory distress syndrome of a chemical nature. Materials and methods. The authors conducted a study on male Wistar rats aged 4 months, weighing 180–190 g. Toxic pulmonary edema was caused by endotracheal administration of 0.1 m HCl solution. The anesthetized patients were intubated using a cannula, after which the researchers intratracheally injected 0.1 M HCl solution at a dose of 2 ml/kg, a decrease in saturation below 80 was expected. Then the experts randomized the animals by weight into groups of 6 individuals each. They connected the animals of the control group to a ventilator. The animals of the experimental group were treated with PFC liquids for an hour, then transferred to a ventilator. Perfluorodecalin was used as a PFC liquid. The scientists recorded heart rate, blood oxygen saturation, rectal temperature, life expectancy and overall survival by group. Results. In the control group, after instillation of 0.1 M HCl solution and connection to a ventilator during the first 25–30 minutes, there was a gradual decrease in SpO2 to 74.0±5.6% (background — 95.0±3.5%) and an increase in heart rate to 182.0±8.6 beats/min., (background — 278.0±14.8 beats/min.) after which there was decompensation of the animal condition. In animals of the experimental group, after connecting to the LALV device, a sharp decrease in heart rate was recorded during the first 5 minutes to 61.0±8.5 beats/min. In turn, saturation did not change significantly throughout the LALV and was in the range from 95 to 100%. As a result of the experiments, it was noted that the average survival time in the experimental group was 256.0±34.5 minutes, which was significantly (p&lt;0.001) more than 5 times higher than this indicator in the control animals — 45.3±4.3 minutes. There were no significant changes in the study of rectal temperature in the animals of the control group. In turn, the animals of the experimental group showed a sharp decrease in rectal temperature during the first 30 minutes from the beginning of LALV, on average by 5.8±1.60°С. As a result of the pathoanatomic autopsy, differences in lung mass coefficients were revealed in different groups. Thus, in the control group and the experimental groups, it was 1.67±0.06 and 2.4±0.045%, respectively. Conclusion. On the model of ARDS caused by endotracheal administration of 0.1M hydrochloric acid solution, it was shown that living with the use of PFC of low temperature liquids, unlike conventional mechanical ventilation, allows for a long time to maintain a stable condition of animals; evacuate a significant amount of edematous fluid from the lungs and thereby increase the duration of their survival. The data presented above indicate that the use of hypothermic LALV can be used to create a "therapeutic window" for ARDS, including its most severe form — the alveolar stage of toxic pulmonary edema. Ethics. Studies involving laboratory animals were conducted in compliance with the following regulations: the Helsinki Declaration of 2000 "On humane treatment of animals", Order No. 755 of the Ministry of Health of the USSR dated 08/12/1977 "Rules for carrying out work using experimental animals", Order No. 199n of the Ministry of Health of the Russian Federation dated 04/01/2016 "On approval of the rules of laboratory practice". The protocol of the study was approved by the Ethics Committee of the Izmerov Research Institute of Occupational Health. Protocol No. 4 dated May 25, 2022.

Performance and safety of volume guarantee ventilation in neonates using the fabian ventilator, a multicenter study.

To evaluate the performance (i.e., agreement between set and measured parameters) and safety (adverse events, device malfunctions, and ventilator alarms) of the fabian HFOi neonatal ventilator in volume guaranteed (VG) mode during conventional ventilation. To analyze the impact of leakage around the endotracheal tube and the set maximum allowed inflating pressure (Pmax). Prospective multicenter observational study. Clinical and ventilator data were collected from 71 infants receiving VG ventilation for ≥12 h in four neonatal intensive care units (NICUs). Ventilator settings, parameters, and alarms were downloaded with 0.5 Hz sampling rate. Data from 4,341 h of ventilation were analyzed. The median (interquartile range, IQR) of the absolute difference between the target and measured expired tidal volume was 0.76 (0.51-1.16) mL/kg. It was less when leak was <50% (median 0.36, IQR: 0.25-0.64 mL/kg, p < .001) and even less when the required peak inflating pressure (PIP) was also below Pmax (median: 0.09 mL/kg, IQR: 0.00-0.16 mL/kg, p < .001). On NICUs setting Pmax higher, tidal volume was maintained significantly closer to target. In 56 patients VG was continued until extubation. Two ventilator malfunctions were reported, none of them resulting in patient harm. "Tidal volume not reached" alarm occurred 32 times hourly, usually lasting for <10 s. The fabian HFOi ventilator maintains tidal volume close to its target, particularly when leak is <50% and when PIP is below Pmax. In most patients VG can be continued until extubation. Despite frequent ventilator alarms, ventilator malfunctions occur very rarely.

A nationwide survey on the management of neonatal respiratory distress syndrome: insights from the MUNICH survey in 394 Chinese hospitals

BackgroundAt present, preterm infants with respiratory distress syndrome (RDS) in China present higher mortality and morbidity rates than those in high-income countries. The aim of this nationwide survey was to assess the clinical management of RDS in China.MethodsA nationwide cross-sectional survey to assess adherence to RDS management recommendations was performed. One neonatologist per hospital was randomly selected. The primary outcome was the key care of RDS management.ResultsAmong the 394 participating hospitals, 88·3% were birthing centres. The number of doctors and nurses per bed were 0·27 and 0·72, respectively. Antenatal corticosteroids (any dose) were administered to 90% of the women at risk of preterm birth at < 34 weeks of gestation (90·0% inborn vs. 50·0% outborn, p < 0·001). The median fraction of inspired oxygen (FiO2) for initial resuscitation was 0·30 for babies born at ≤ 32 weeks of gestation and 0·25 for those born at > 32 weeks. T-piece resuscitators were available in 77·8% of delivery rooms (DRs) (tertiary hospitals: 82·5% vs. secondary hospitals: 63·0%, p < 0·001). Surfactant was used in 51·6% of the DRs. Less invasive surfactant administration (LISA) was used in 49·7% of the hospitals (tertiary hospitals: 55·3% vs. secondary hospitals: 31·5%, p < 0·001). Primary non-invasive ventilation was initiated in approximately 80·0% of the patients. High-frequency oscillation ventilation was primarily reserved for rescue after conventional mechanical ventilation (MV) failure. Caffeine was routinely used during MV in 59·1% of the hospitals. Bedside lung ultrasonography was performed in 54·3% of the health facilities (tertiary hospitals: 61·6% vs. secondary hospitals: 30·4%, p < 0·001). Qualified breast milk banks and Family Integrated Care (FICare) were present in 30·2% and 63·7% of the hospitals, respectively.ConclusionsSignificant disparities in resource availability and guidelines adherence were evident across hospitals. Future strategies should address DR facilities and medication access, technical training, staff allocation, and ancillary facility development for a better management of RDS patients in China.

Effect of body position during weaning from total liquid ventilation in piglets

ObjectiveTo determine if change in body position improves oxygen requirements and respiratory mechanics during the transition from total liquid ventilation (TLV) to gas ventilation. MethodsFourteen piglets underwent TLV, followed by a 2-hour weaning period under conventional gas ventilation. Subjects were randomized to the experimental group (Rotating – R), that was in prone position between the 10th and 30th minute of weaning, or to the static control group (Supine – S). ResultsOxygenation index was lower in the R group at 30 minutes in prone position than that in the S group (1.9 [1.6; 2.8] vs 3.5 [3.1; 5.1], p = 0.001). This difference disappeared when subjects resumed the supine position (4.2 [3.8; 4.7] and 4.7 [3.8; 5.4], p = 0.4, for the R and S groups, respectively). The change in body position did not affect respiratory system compliance or inspiratory capacity. ConclusionProne position improved oxygenation during weaning from TLV. The effect disappeared once piglets returned to the supine position.

Effect of perioperative sigh ventilation on postoperative hypoxemia and pulmonary complications after on-pump cardiac surgery (E-SIGHT): study protocol for a randomized controlled trial

BackgroundPostoperative hypoxemia and pulmonary complications remain a frequent event after on-pump cardiac surgery and mostly characterized by pulmonary atelectasis. Surfactant dysfunction or hyposecretion happens prior to atelectasis formation, and sigh represents the strongest stimulus for surfactant secretion. The role of sigh breaths added to conventional lung protective ventilation in reducing postoperative hypoxemia and pulmonary complications among cardiac surgery is unknown.MethodsThe perioperative sigh ventilation in cardiac surgery (E-SIGHT) trial is a single-center, two-arm, randomized controlled trial. In total, 192 patients scheduled for elective cardiac surgery with cardiopulmonary bypass (CPB) and aortic cross-clamp will be randomized into one of the two treatment arms. In the experimental group, besides conventional lung protective ventilation, sigh volumes producing plateau pressures of 35 cmH2O (or 40 cmH2O for patients with body mass index > 35 kg/m2) delivered once every 6 min from intubation to extubation. In the control group, conventional lung protective ventilation without preplanned recruitment maneuvers is used. Lung protective ventilation (LPV) consists of low tidal volumes (6–8 mL/kg of predicted body weight) and positive end-expiratory pressure (PEEP) setting according to low PEEP/FiO2 table for acute respiratory distress syndrome (ARDS). The primary endpoint is time-weighted average SpO2/FiO2 ratio during the initial post-extubation hour. Main secondary endpoint is the severity of postoperative pulmonary complications (PPCs) computed by postoperative day 7.DiscussionThe E-SIGHT trial will be the first randomized controlled trial to evaluate the impact of perioperative sigh ventilation on the postoperative outcomes after on-pump cardiac surgery. The trial will introduce and assess a novel perioperative ventilation approach to mitigate the risk of postoperative hypoxemia and PPCs in patients undergoing cardiac surgery. Also provide the basis for a future larger trial aiming at verifying the impact of sigh ventilation on postoperative pulmonary complications.Trial registrationClinicalTrials.gov NCT06248320. Registered on January 30, 2024. Last updated February 26, 2024.

Accuracy and Interpretation of Transcutaneous Carbon Dioxide Monitoring in Critically Ill Children.

Transcutaneous carbon dioxide (Tc co2 ) monitoring can noninvasively assess ventilation by estimating carbon dioxide ( CO2 ) levels in the blood. We aimed to evaluate the accuracy of Tc co2 monitoring in critically ill children by comparing it to the partial pressure of arterial carbon dioxide (Pa co2 ). In addition, we sought to determine the variation between Tc co2 and Pa co2 acceptable to clinicians to modify patient care and to determine which patient-level factors may affect the accuracy of Tc co2 measurements. Retrospective observational cohort study. Single, quaternary care PICU from July 1, 2012, to August 1, 2020. Included participants were admitted to the PICU and received noninvasive ventilation support (i.e., continuous or bilevel positive airway pressure), conventional mechanical ventilation, or high-frequency oscillatory or percussive ventilation with Tc co2 measurements obtained within 15 minutes of Pa co2 measurement. None. Three thousand four hundred seven paired arterial blood gas and Tc co2 measurements were obtained from 264 patients. Bland-Altman analysis revealed a bias of -4.4 mm Hg (95% CI, -27 to 18.3 mm Hg) for Tc co2 levels against Pa co2 levels on the first measurement pair for each patient, which fell within the acceptable range of ±5 mm Hg stated by surveyed clinicians, albeit with wide limits of agreement. The sensitivity and specificity of Tc co2 to diagnose hypercarbia were 93% and 71%, respectively. Vasoactive-Infusion Score (VIS), age, and self-identified Black/African American race confounded the relationship between Tc co2 with Pa co2 but percent fluid overload, weight-for-age, probe location, and severity of illness were not significantly associated with Tc co2 accuracy. Tc co2 monitoring may be a useful adjunct to monitor ventilation in children with respiratory failure, but providers must be aware of the limitations to its accuracy.

Low-Frequency Ventilation May Facilitate Weaning in Acute Respiratory Distress Syndrome Treated with Extracorporeal Membrane Oxygenation: A Randomized Controlled Trial.

Although extracorporeal membrane ventilation offers the possibility for low-frequency ventilation, protocols commonly used in patients with acute respiratory distress syndrome (ARDS) and treated with extracorporeal membrane oxygenation (ECMO) vary largely. Whether strict adherence to low-frequency ventilation offers benefit on important outcome measures is poorly understood. Background/Objectives: This pilot clinical study investigated the efficacy of low-frequency ventilation on ventilator-free days (VFDs) in patients suffering from ARDS who were treated with ECMO therapy. Methods: In this single-center randomized controlled trial, 44 (70% male) successive ARDS patients treated with ECMO (aged 56 ± 12 years, SAPS III 64 (SD ± 14)) were randomly assigned 1:1 to the control group (conventional ventilation) or the treatment group (low-frequency ventilation during first 72 h on ECMO: respiratory rate 4-5/min; PEEP 14-16 cm H2O; plateau pressure 23-25 cm H2O, tidal volume: <4 mL/kg). The primary endpoint was VFDs at day 28 after starting ECMO treatment. The major secondary endpoint was ICU mortality, 28-day mortality and 90-day mortality. Results: Twenty-three (52%) patients were successfully weaned from ECMO and were discharged from the intensive care unit (ICU). Twelve patients in the treatment group and five patients in the control group showed more than one VFD at day 28 of ECMO treatment. VFDs were 3.0 (SD ± 5.5) days in the control group and 5.4 (SD ± 6) days in the treatment group (p = 0.117). Until day 28 of ECMO initiation, patients in the treatment group could be successfully weaned off of the ventilator more often (OR of 0.164 of 0 VFDs at day 28 after ECMO start; 95% CI 0.036-0.758; p = 0.021). ICU mortality did not differ significantly (36% in treatment group and 59% in control group; p = 0.227). Conclusions: Low-frequency ventilation is comparable to conventional protective ventilation in patients with ARDS who have been treated with ECMO. However, low-frequency ventilation may support weaning from invasive mechanical ventilation in patients suffering from ARDS and treated with ECMO therapy.

Novel High-tech, Low-cost Ventilation for Military Use, Mass Casualty Incidents, Stockpiling, and Underserved Communities.

Despite the significant need for mechanical ventilation in- and out-of-hospital, mechanical ventilators remain inaccessible in many instances because of cost or size constraints. Mechanical ventilation is especially critical in trauma scenarios, but the impractical size and weight of standard mechanical ventilators restrict first responders from carrying them in medical aid bags, leading to reliance on imprecise manual bag-mask ventilation. This is particularly important in combat-related injury, where airway compromise and respiratory failure are leading causes of preventable death, but medics are left without necessary mechanical ventilation. To address the serious gaps in mechanical ventilation accessibility, we are developing an Autonomous, Modular, and Portable Ventilation platform (AMP-Vent) suitable for austere environments, prolonged critical care, surgical applications, mass casualty incidents, and stockpiling. The core system is remarkably compact, weighing <2.3 kg, and can fit inside a shoebox (23.4 cm × 17.8 cm × 10.7 cm). Notably, this device is 65% lighter than standard transport ventilators and astoundingly 96% lighter than typical intensive care unit ventilators. Beyond its exceptional portability, AMP-Vent can be manufactured at less than one-tenth the cost of conventional ventilators. Despite its reduced size and cost, the system's functionality is uncompromised. The core system is equipped with closed-loop sensors and advanced modes of ventilation (pressure-control, volume-control, and synchronized intermittent mandatory ventilation), enabling quality care in a portable form factor. The current prototype has undergone preliminary preclinical testing and optimization through trials using a breathing simulator (ASL 5000) and in a large animal model (swine). This report aims to introduce a novel ventilation system and substantiate its promising performance through evidence gathered from preclinical studies. Lung simulator testing was performed using the ASL 5000, in accordance with table201.105 "pressure-control inflation-type testing" from ISO 80601-2-12:2020. Following simulations, AMP-Vent was tested in healthy 10-kg female domestic piglets. The Children's Hospital of Philadelphia Institutional Animal Care and Use Committee approved all animal procedures. Swine received 4-min blocks of alternating ventilation, where AMP-Vent and a conventional anesthesia ventilator (GE AISYS CS2) were used to titrate to varied end-tidal carbon dioxide (EtCO2) goals with the initial ventilator switching for each ascending target (35, 40, 45, 50, 55 mmHg). During ASL 5000 simulations, AMP-Vent exhibited consistent performance under varied conditions, maintaining a coefficient of variation of 2% or less within each test. In a large animal study, AMP-Vent maintained EtCO2 and SpO2 targets with comparable performance to a conventional anesthesia ventilator (GE AISYS CS2). Furthermore, the comparison of minute ventilation (Ve) distributions between the conventional anesthesia ventilator and AMP-Vent at several EtCO2 goals (35, 40, 45, 50, and 55 mmHg) revealed no statistically significant differences (p = 0.46 using the Kruskal-Wallis rank sum test). Preclinical results from this study highlight AMP-Vent's core functionality and consistent performance across varied scenarios. AMP-Vent sets a benchmark for portability with its remarkably compact design, positioning it to revolutionize trauma care in previously inaccessible medical scenarios.

Extracorporeal membrane oxygenation as life-saving bridge for patients with airway obstruction caused by neck and chest tumors to salvage procedure: an in-depth review

Narrowed or stenotic airways are frequently encountered in emergency practice. Neck and chest tumors-caused airway obstruction usually follow a severe clinical course, necessitating urgent ventilation as a bridge to perform emergency operations. In certain cases, traditional ventilation methods may not safely address complicated airway conditions. In such instances, a special cardiopulmonary support becomes necessary to manage both hemodynamics and ventilation for patients. Extracorporeal membrane oxygenation (ECMO) is considered a last-resort treatment for respiratory failure. When dealing with emergency difficult airway situations, ECMO offers certain advantages over conventional ventilation. However, its effectiveness in managing airway obstruction due to solid tumor located in neck or chest is not well-established due to limited clinical practice. Published articles about this topic are still limited, and primarily rely on case series and reports. As a result, they offer insufficient data and illustrations to fully elucidate emergency issues. In the present article, we summarize the existing literature concerning ECMO utility in managing patients with airway obstruction due to solid tumor located in neck or chest based on PubMed, Web of Science, and other medical databases, to conduct an in-depth review. We conducted an analysis of 27 studies, including a total of 54 patients with airway obstruction caused by tumors. All patients underwent surgical relief of airway obstruction with ECMO as ventilatory support. Postoperatively, 87% of the patients (47/54) survived. 7.4% of the patients (4/54) died due to postoperative disease progression, unrelated to ECMO complications. The prognosis of 5.6% of the patients (3/54) could not be obtained. Additionally, we present an interesting case series (n=5) based on a real-world research to demonstrate the different outcomes among airway-obstructed patients due to neck and chest masses. In this series, four patients supported by ECMO successfully discharged postoperatively, while one patient on conventional ventilation died due to respiratory collapse before surgery. Meanwhile, we share novel illustrations and clinical figures to supplement the understanding of this condition. The findings presented in this article provide a basis for further studies and can be used to improve management of the patients.

Flow-controlled expiration ventilation using a piston ventilator: effects of expiration time and speed on respiratory and pulmonary mechanics with focus on hysteresis and compliance in healthy horses.

To investigate the effects of FLow-controlled EXpiration (FLEX) ventilation expiration time and speed on respiratory and pulmonary mechanics in anesthetized horses in dorsal recumbency. 6 healthy adult research horses. In this randomized crossover experimental study, horses were anesthetized 3 times and were ventilated each time for 60 minutes using conventional volume-controlled ventilation (VCV), linear emptying of the lung over 50% of the expiratory time (FLEX50), or linear emptying of the lung over 100% of the expiratory time (FLEX100) in a randomized order. The primary outcome variables were dynamic compliance (Cdyn), hysteresis, and alveolar dead space. The data was analyzed using two-factor ANOVA. Significance was set to P < .05. Horses ventilated using FLEX50 and FLEX100 showed significantly higher Cdyn and significantly lower hysteresis values compared to horses ventilated using VCV. Horses ventilated using FLEX50 had significantly lower alveolar dead space compared to horses ventilated using FLEX100 or VCV. Horses ventilated using FLEX100 had significantly lower alveolar dead space compared to VCV horses. Our results demonstrate improved Cdyn, hysteresis, and alveolar dead space in horses ventilated with either FLEX50 or FLEX100 relative to traditional VCV. The use of FLEX with a faster exhalation speed (FLEX50) offers additional respiratory advantages.

Effect of automated versus conventional ventilation on mechanical power of ventilation-A randomized crossover clinical trial.

Mechanical power of ventilation, a summary parameter reflecting the energy transferred from the ventilator to the respiratory system, has associations with outcomes. INTELLiVENT-Adaptive Support Ventilation is an automated ventilation mode that changes ventilator settings according to algorithms that target a low work-and force of breathing. The study aims to compare mechanical power between automated ventilation by means of INTELLiVENT-Adaptive Support Ventilation and conventional ventilation in critically ill patients. International, multicenter, randomized crossover clinical trial in patients that were expected to need invasive ventilation > 24 hours. Patients were randomly assigned to start with a 3-hour period of automated ventilation or conventional ventilation after which the alternate ventilation mode was selected. The primary outcome was mechanical power in passive and active patients; secondary outcomes included key ventilator settings and ventilatory parameters that affect mechanical power. A total of 96 patients were randomized. Median mechanical power was not different between automated and conventional ventilation (15.8 [11.5-21.0] versus 16.1 [10.9-22.6] J/min; mean difference -0.44 (95%-CI -1.17 to 0.29) J/min; P = 0.24). Subgroup analyses showed that mechanical power was lower with automated ventilation in passive patients, 16.9 [12.5-22.1] versus 19.0 [14.1-25.0] J/min; mean difference -1.76 (95%-CI -2.47 to -10.34J/min; P < 0.01), and not in active patients (14.6 [11.0-20.3] vs 14.1 [10.1-21.3] J/min; mean difference 0.81 (95%-CI -2.13 to 0.49) J/min; P = 0.23). In this cohort of unselected critically ill invasively ventilated patients, automated ventilation by means of INTELLiVENT-Adaptive Support Ventilation did not reduce mechanical power. A reduction in mechanical power was only seen in passive patients. Clinicaltrials.gov (study identifier NCT04827927), April 1, 2021. https://clinicaltrials.gov/study/NCT04827927?term=intellipower&rank=1.

New noninvasive modalities in long-term pediatric ventilation: a scoping review.

Long-term noninvasive ventilation modalities for the pediatric population have undergone a continuous evolution. Hybrid noninvasive ventilation modalities have been recently introduced in clinical practice. Combining the advantages of conventional ventilation, hybrid modes use algorithms that automatically adjust the ventilator's settings to achieve a predefined ventilation target. Most of the recommendations on the use and settings of hybrid noninvasive ventilation modalities in children are derived from adult experience. Therefore, there is a lack of evidence on its implementation in pediatric chronic respiratory diseases. This scoping review aims to map the existing information regarding the use of hybrid ventilation modalities in the pediatric population and identify knowledge or research gaps. We performed a literature search using MEDLINE and Pubmed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews. We included 13 studies (ten studies on average volume-assured pressure-support ventilation; two studies on intelligent volume-assured pressure-support ventilation; and one study on adaptive servoventilation). The use of new noninvasive ventilation modes in the pediatric population has been applied for the treatment of neuromuscular and hypoventilation syndromes as an alternative therapeutic option in the case of the failure of conventional noninvasive ventilation. Their widespread use has been hampered by the limited evidence available. Longitudinal studies on a larger number of patients are needed to confirm their effectiveness and evaluate their long-term clinical and functional outcomes.

Outcome of Veno-Pulmonary Extracorporeal Life Support in Lung Transplantation Using ProtekDuo Cannula: A Systematic Review and Description of Configurations.

Background: Refractory end-stage pulmonary failure may benefit from extracorporeal life support (ECLS) as a bridge to lung transplantation. Veno-venous (VV) extracorporeal membrane oxygenation (ECMO) has been recommended for patients who have failed conventional medical therapy and mechanical ventilation. Veno-arterial (VA) ECMO may be used in patients with acute right ventricular (RV) failure, haemodynamic instability, or refractory respiratory failure. Peripheral percutaneous approaches, either dual-site single-lumen cannulation for veno-pulmonary (VP) ECMO or single-site dual-lumen (dl)VP ECMO, using the ProtekDuo right ventricular assist device (RVAD) cannula, has made this configuration a desirable option as a bridge to transplantation. These configurations support the right ventricle, prevent recirculation by placing the tricuspid and pulmonary valve between the drainage and return cannulas, provide the direct introduction of oxygenated blood into the pulmonary artery, and have been shown to decrease the incidence of acute kidney injury (AKI), requiring continuous renal replacement therapy (CRRT) in certain disease states. This promotes haemodynamic stability, potential sedation-weaning trials, extubation, mobilisation, and pre-transplant rehabilitation. Methods: A web-based literature search in PubMed and EMBASE was undertaken based on a combination of keywords. The PICOS and PRISMA approaches were used. Results: Four case series were identified out of 323 articles, with a total of 34 patients placed on VP ECMO as a bridge to lung transplantation. All relevant data are reviewed and integrated into the Discussion. Conclusions: Despite the limited available evidence, the use of ProtekDuo has become very promising for the management of end-stage lung disease as a bridge to lung transplantation.

POStoperative INTELLiVENT-adaptive support VEntilation in cardiac surgery patients (POSITiVE) II—study protocol of a randomized clinical trial

BackgroundOne single-center randomized clinical trial showed that INTELLiVENT-adaptive support ventilation (ASV) is superior to conventional ventilation with respect to the quality of ventilation in post-cardiac surgery patients. Other studies showed that this automated ventilation mode reduces the number of manual interventions at the ventilator in various types of critically ill patients. In this multicenter study in patients post-cardiac surgery, we test the hypothesis that INTELLiVENT-ASV is superior to conventional ventilation with respect to the quality of ventilation.Methods“POStoperative INTELLiVENT-adaptive support VEntilation in cardiac surgery patients II (POSITiVE II)” is an international, multicenter, two-group randomized clinical superiority trial. In total, 328 cardiac surgery patients will be randomized. Investigators screen patients aged > 18 years of age, scheduled for elective cardiac surgery, and expected to receive postoperative ventilation in the ICU for longer than 2 h. Patients either receive automated ventilation by means of INTELLiVENT-ASV or ventilation that is not automated by means of a conventional ventilation mode. The primary endpoint is quality of ventilation, defined as the proportion of postoperative ventilation time characterized by exposure to predefined optimal, acceptable, and critical (injurious) ventilatory parameters in the first two postoperative hours. One major secondary endpoint is ICU team staff workload, captured by the ventilator software collecting manual settings on alarms. Patient-centered endpoints include duration of postoperative ventilation and length of stay in ICU.DiscussionPOSITiVE II is the first international, multicenter, randomized clinical trial designed to confirm that POStoperative INTELLiVENT-ASV is superior to non-automated conventional ventilation and secondary to determine if this closed-loop ventilation mode reduces ICU team staff workload. The results of POSITiVE II will support intensive care teams in their choices regarding the use of automated ventilation in postoperative care of uncomplicated cardiac surgery patients.Trial registrationClinicaltrials.gov NCT06178510. Registered on December 4, 2023.

Ventilator strategies in congenital diaphragmatic hernia

This review focuses on contemporary mechanical ventilator practices used in the initial management of neonates born with congenital diaphragmatic hernia (CDH). Both conventional and non-conventional ventilation modes in CDH are reviewed. Special emphasis is placed on the rationale for gentle ventilation and the current evidence-based clinical practice guidelines that are recommended for supporting these fragile infants. The interplay between CDH lung hypoplasia and other key cardiopulmonary elements of the disease, namely a reduced pulmonary vascular bed, abnormal pulmonary vascular remodeling, and left ventricular hypoplasia, are discussed. Finally, we provide insights into future avenues for mechanical ventilator research in CDH.

Association between initial ventilation mode and hospital outcomes for severe congenital diaphragmatic hernia

ObjectiveTo determine the association between initial delivery room (DR) ventilator (conventional mechanical ventilation [CMV] versus high frequency oscillatory ventilation [HFOV] and hospital outcomes for infants with severe congenital diaphragmatic hernia (CDH).Study designQuasi-experimental design before/after introducing a clinical protocol promoting HFOV. The primary outcome was first blood gas parameters. Secondary outcomes included serial blood gas assessments, ECMO, survival, duration of ventilation, and length of hospitalization.ResultsFirst pH and CO2 were more favorable in the HFOV group (n = 75) than CMV group (n = 85), median (interquartile range (IQR)) pH 7.18 (7.03, 7.24) vs. 7.05 (6.93, 7.17), adjusted p-value < 0.001; median CO2 62.0 (46.0, 82.0) vs 85.9 (59.0, 103.0), adjusted p-value < 0.001. ECMO, survival, duration of ventilation, and length of hospitalization did not differ between groups in adjusted analysis.ConclusionAmong infants with severe CDH, initial DR HFOV was associated with improved early gas exchange with no adverse differences in hospital outcomes.