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Abstract Background Endotracheal intubation and mechanical ventilation are prevalent interventions in the operating room and intensive care unit. Recently, the complications of endotracheal tube cuff pressure have been a topic of interest. Therefore, this study compared the effect of pressure control and volume control ventilation modes on the endotracheal cuff pressure rate in patients undergoing general anesthesia and mechanical ventilation. Methods In this triple-blinded randomized clinical trial, 50 patients undergoing open limb surgery and inguinal hernia were allocated to two groups of 25 based on inclusion criteria. After intubation, one group underwent ventilation on the pressure control ventilation mode, and the other underwent ventilation on the volume control ventilation mode. In both groups, using a manometer, the cuff’s pressure was first adjusted in the range of 25–30 cm of water. Then, the cuff pressure was measured at 10, 20, and 30 min intervals. The data were statistically analyzed using independent t-test, and two-way repeated measures ANOVA. Results The present study’s findings showed that cuff pressure has significantly decreased over time in both study groups (F = 117.7, P

Background: Endotracheal intubation and mechanical ventilation are prevalent interventions in the operating room and intensive care unit. Recently, the complications of endotracheal tube cuff pressure have been a topic of interest. Therefore, this study compared the effect of pressure control and volume control ventilation modes on the endotracheal cuff pressure rate in patients undergoing general anesthesia and mechanical ventilation. Methods: In this triple-blinded randomized clinical trial, 50 patients undergoing open limb surgery and inguinal hernia were allocated to two groups of 25 based on inclusion criteria. After intubation, one group underwent ventilation on the pressure control ventilation mode, and the other underwent ventilation on the volume control ventilation mode. In both groups, using a manometer, the cuff's pressure was first adjusted in the range of 25–30 cm of water. Then, the cuff pressure was measured at 10, 20, and 30 min intervals. The data were statistically analyzed using independent t-test, and two-way repeated measures ANOVA. Results: The present study's findings showed that cuff pressure has significantly decreased over time in both study groups (F = 117.7, P < 0.001). However, a repeated measures ANOVA with a Greenhouse-Geisser correction showed no interaction between time and groups (F = 0.019, P = 0.98). The two groups had no significant difference in cuff pressure (F = 0.56, P = 0.458). Conclusion: Since the cuff pressure has been significantly reduced in both groups over time, continuous monitoring of endotracheal tube cuff pressure in patients undergoing mechanical ventilation is essential. Therefore, it is suggested to keep the cuff pressure within the recommended range to prevent complications resulting from cuff pressure reduction, such as aspiration and ventilation decrease. Trial registration: The study was registered in the Iranian Registry of Clinical Trial on 23/02/2019 (trial registration number: IRCT20181018041376N1). [ABSTRACT FROM AUTHOR]

Background: Mechanical power (MP) applied to the respiratory system (MP RS ) is associated with ventilator-induced lung injury (VILI) and ARDS mortality. Absent automated ventilator MP RS measurements, the alternative is clinically unwieldy equations. However, simplified surrogate formulas are now available and accurately reflect values produced by airway pressure-volume curves. This retrospective, observational study examined whether the surrogate pressure -control equation alone could accurately assess mortality risk in subjects with ARDS managed almost exclusively with volume control (VC) ventilation. Methods: Nine hundred and forty-eight subjects were studied in whom invasive mechanical ventilation and implementation of ARDS Network ventilator protocols commenced ≤ 24 h after ARDS onset and who survived > 24 h. MP RS was calculated as 0.098 x breathing frequency x tidal volume x (PEEP + driving pressure). MP RS was assessed as a risk factor for hospital mortality and compared between non-survivors and survivors across Berlin definition classifications. In addition, mortality was compared across 4 MP RS thresholds associated with VILI or mortality (ie, 15, 20, 25, and 30 J/min). Results: MP RS was associated with increased mortality risk: odds ratio (95% CI) of 1.06 (1.04-1.07) J/min ( P  < .001). Median MP RS differentiated non-survivors from survivors in mild (24.7 J/min vs 18.5 J/min, respectively, P  = .034), moderate (25.7 J/min vs 21.3 J/min, respectively, P  < .001), and severe ARDS (28.7 J/min vs 23.5 J/min, respectively, P  < .001). Across 4 MP RS thresholds, mortality increased from 23-29% when MP RS was ≤ threshold versus 38-51% when MP RS was > threshold ( P  < .001). In the > cohort, the odds ratio (95% CI) increased from 2.03 (1.34-3.12) to 2.51 (1.87-3.33). Conclusion: The pressure control surrogate formula is sufficiently accurate to assess mortality in ARDS, even when using VC ventilation. In our subjects when MP RS exceeds established cutoff values for VILI or mortality risk, we found mortality risk consistently increased by a factor of > 2.0.

This review compares the safety and effectiveness of volume control ventilation (VCV) and pressure control ventilation (PCV) during laparoscopic surgery. Nine studies were chosen for in-depth examination following the application of stringent inclusion and exclusion criteria to the 184 publications that the literature search turned up. PCV is well-known for its capacity to preserve lower peak airway pressures during laparoscopic procedures, lowering the risk of volutrauma and barotrauma and enhancing oxygenation under these conditions of elevated intra-abdominal pressures. On the other hand, VCV guarantees a constant tidal volume and offers accurate ventilation management, both of which are essential for preserving stable carbon dioxide levels. VCV, however, may result in higher peak airway pressures, raising the risk of lung damage brought on by a ventilator. Research indicates that PCV provides better respiratory mechanics management during laparoscopic surgery, but VCV consistent tidal volume delivery is useful in some clinical situations. When choosing between PCV and VCV, the anesthesia team's experience, the demands of each patient, and the surgical circumstances should all be taken into consideration. Real-time monitoring tools and sophisticated ventilatory technology are essential for maximizing ventilation techniques. Further improving patient outcomes can be achieved by incorporating multimodal anesthesia approaches, such as the use of muscle relaxants and customized intraoperative fluid management. Muscle relaxants optimize conditions for mechanical ventilation by ensuring adequate muscle relaxation, reducing the risk of ventilator-associated lung injury, and enabling more precise control of ventilation parameters. Tailored intraoperative fluid management helps maintain optimal lung mechanics by avoiding fluid overload, which can lead to pulmonary edema and compromised gas exchange, necessitating adjustments in ventilation strategy. While both ventilation modalities can be utilized efficiently, the research suggests that PCV may be more advantageous in controlling oxygenation and airway pressures. In the dynamic and demanding world of laparoscopic surgery, ongoing research and clinical innovation are crucial to improving these tactics and guaranteeing the best possible treatment. In order to obtain the best possible patient outcomes during laparoscopic surgeries, this review emphasizes the significance of customized breathing techniques., Competing Interests: Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Sawant et al.)

Non-invasive ventilation is increasingly used in children for acute and chronic respiratory failure. Ventilators available for clinical use have different levels of complexity, and clinicians need to know in detail their characteristics, setting variables, and performances. A wide range of ventilators are currently used in non-invasive ventilation including bi-level ventilators, intermediate ventilators, and critical care ventilators. Simple or advanced continuous positive airway pressure devices are also available. Differences between ventilators may have implications on the development of asynchronies and air leaks and may be associated with discomfort and poor patient tolerance. Although pressure-targeted (controlled) mode is preferable in children because of barotrauma concerns, volume-targeted (controlled) ventilators are also available. Pressure support ventilation represents the most used non-invasive ventilation mode, as it is more physiological. The newest ventilators allow the clinicians to use the hybrid modes that combine the advantages of volume- and pressure-targeted (controlled) ventilation while limiting their drawbacks. The use of in-built software may help clinicians to optimize the ventilator setting as well as to objectively monitor patient adherence to the treatment. The present review aims to help the clinician with the choice of the ventilator and its ventilation modalities to ensure a successful non-invasive ventilation program.

In severe respiratory insufficiency, neonatal and pediatric patients should be ventilated artificially by a ventilator. Aim of this experimental study was to evaluate whether the newly developed ventilator Chirana Aura V may effectively ventilate the lungs of animals with two different models of acute lung injury: acute respiratory distress syndrome (ARDS) induced by repetitive saline lavage and meconium aspiration syndrome (MAS) induced by intratracheal instillation of neonatal meconium. The experiments were performed on 10 adult rabbits (New Zealand white). In ARDS group (n=5), the lungs were repetitively lavaged with saline (30 ml/kg) until partial pressure of oxygen (PaO2) in arterial blood was under 26.7 kPa at inspiratory fraction of oxygen FiO2=1.0. In MAS group (n=5), animals were instilled 4 ml/kg of suspension of human meconium (25 mg/ml). When the model of acute lung injury was developed, animals were ventilated for additional 2 hours with pressure control ventilation (PCV) regime by ventilator Chirana Aura V. Ventilatory parameters, blood gases, acid-base balance, end-tidal CO2, O2 saturation of hemoglobin, oxygenation indexes, ventilation efficiency index, dynamic lung compliance, and right-to-left pulmonary shunts were measured and calculated in regular time intervals. In both experimental groups, used ventilatory settings provided acceptable gas exchange within the period of observation. Thus, the results indicate that ventilator Chirana Aura V might be suitable for ventilation of animal models of acute lung injury. However, further pre-clinical investigation is needed before its use may be recommended in neonatal and/or pediatric patients with acute lung injury.

Aim: To observe the 28 and 90 days mortality associated with prone position and assist control-pressure control (with inverse ratio) ventilation (ACPC-IRV). Materials and Methods: All patients who were admitted to our medical Intensive Care Unit (ICU) who are positive for H1N1 viral infection with severe acute respiratory distress syndrome (ARDS) and requiring invasive mechanical ventilation in prone position were included in our prospective observational study. Six patients who are positive for H1N1 required invasive ventilation in prone position. These patients were planned to ventilate in prone for 16 h and in supine for 8 h daily until P/F ratio >150 with FiO2 of 0.6 or less and positive end-expiratory pressure <10 cm of H2O. Results: At admission, among these six patients the mean tidal volume generated was about 376.6 ml which was in the range of 6-8 ml/kg predicted body weight. The mean lung injury score was 3.79, mean PaO2/FiO2 ratio was 52.66 and mean oxygenation index was 29.83. The mean duration of ventilation was 9.4 days (225.6 h). The ICU length of stay was 11.16 days. There was no mortality at 28 and 90 days. Conclusion: Early prone combined with ACPC-IRV in H1N1 patients having severe ARDS can be used as a rescue therapy and it should be confirmed by large observational studies. [ABSTRACT FROM AUTHOR]

Background: Atelectasis and pneumonia are highly prevalent in patients under mechanical ventilation. Studies indicate that using ventilation with an open lung concept improves recovery, decreases ventilator-related pneumonia, decreases mortality and leads to faster weaning from the ventilator. Therefore, this study investigated the effect of higher airway pressure on ventilator-associated pneumonia., Methods: This randomized clinical trial was conducted on 120 patients under mechanical ventilation. The patients were divided into two groups based on ventilator pressure: the control group (pressure level 20) and the intervention group (pressure level 30). Demographic data, disease severity, the incidence of ventilator-associated pneumonia, organ damage, days connected to the ventilator, length of hospitalization in ICU, and mortality were compared between the two groups., Results: There was no significant difference in demographic data and disease severity between the two groups. The average Clinical Pulmonary Infection Score in the intervention group was significantly lower than the control group (P = 0.02). The intervention group's average Sequential Organ Failure Assessment score was significantly lower than the control group (p = 0.016)., Conclusions: High-pressure levels can decrease ventilator-associated pneumonia and organ failure. It is recommended that the study be repeated with a larger, more diverse population., Competing Interests: Declaration of Competing Interest There is no conflict of interest in this article., (Copyright © 2022 Southern Society for Clinical Investigation. Published by Elsevier Inc. All rights reserved.)

• A physiologically relevant, predictive lung mechanics virtual patient model. • Nonlinear elastance evolution is captured and predicted with the newly proposed function. • Pressure–volume loops and peak pressures/volumes are accurately predicted. • The model is validated for both pressure controlled and volume controlled mechanical ventilation modes. • The basis function approach used is computationally fast and can be implemented for real-time. Mechanical ventilation (MV) is a core treatment for patients suffering from respiratory disease and failure. However, MV settings are not standardized due to significant inter- and intra- patient variability in response to care, leading to variability in outcome. There is thus a need to personalize MV settings. This research significantly extends a single compartment lung mechanics model with physiologically relevant basis functions, and uses it to identify patient-specific lung mechanics and predict response to changes in MV settings. Nonlinear evolution of pulmonary elastance over positive end expiratory pressure (PEEP) is modelled by a newly proposed, physiologically relevant and simplified compensatory function to enable prediction of pulmonary response for both volume-controlled ventilation (VCV) and pressure-controlled ventilation (PCV), and identified as patient-specific using each patient's data at a baseline PEEP. Predictions at higher PEEP levels test the validity of the proposed models based on errors in predicted peak inspiratory pressure (PIP) in two VCV trials and volume (PIV) in one PCV trial. A total of 210 prediction cases over 36 patients (22 VCV; 14 PCV) yielded absolute predicted PIP errors within 1.0 cmH 2 O (2.3%) and 3.3 cmH 2 O (7.3%) for 90% cases in VCV, while predicted PIV errors are within 0.073 L (16.8%) for 85% cases in PCV. In conclusion, a novel deterministic virtual patient model is presented, able to offer accurate prediction of pulmonary response across a wide range of PEEP changes for the two main MV modes used clinically, enabling predictive decision support in real-time to safely personalize and optimize care. [ABSTRACT FROM AUTHOR]

Objective: To demonstrate in experimental animals with respiratory insufficiency that under well-defined conditions, commercially available ventilators allow settings which are as effective as high frequency oscillatory ventilators (HFOV), with respect to the levels of gas exchange, protein infiltration, and lung stability. Design: Prospective, randomized, animal study. Setting: Experimental laboratory of a university. Subjects: 18 adult male Sprague-Dawley rats. Interventions: Lung injury was induced by repeated whole-lung lavage. Thereafter, the animals were assigned to pressure-controlled ventilation (PCV) plus The Open Lung Concept (OLC) or HFOV plus OLC (HFOOLC). In both groups, an opening maneuver was performed by increasing airway pressures to improve the arterial oxygen tension/fractional inspired oxygen (PaO2/FIO2) ratio to L 500 mm Hg; thereafter, airway pressures were reduced to minimal values, which kept PaO2/FIO2 L 500 mm Hg. Pressure amplitude was adjusted to keep CO2 as close as possible in the normal range. Measurements and results: Airway pressure, blood gas tension, and arterial blood pressure were recorded every 30 min. At the end of the 3-h study period, a pressure-volume curve was recorded and bronchoalveolar lavage was performed to determine protein content. After the recruitment maneuver, the resulting mean airway pressure to keep a PaO2/FIO2 L 500 mm Hg was 25 ± 1.3 cm H2O during PCVOLC and 25 ± 0.5 cm H2O during HFOVOLC. Arterial oxygenation in both groups was above L 500 mm Hg and arterial carbon dioxide tension was kept close to the normal range. No differences in mean arterial pressure, lung mechanics and protein influx were found between the two groups. Conclusions: This study shows that in surfactant-deficient animals, PCV, in combination with a recruitment maneuver, opens atelectatic lung areas and keeps them open as effectively as HFOV. [ABSTRACT FROM AUTHOR]

Objective . The measurement of the static compliance of the respiratory system ( C stat ) during mechanical ventilation requires zero end-inspiratory flow. An inspiratory pause maneuver is needed if the zero end-inspiratory flow condition cannot be satisfied under normal ventilation. Approach ) under pressure control ventilation mode without the inspiratory pause maneuver. First, a screening strategy was applied to filter out breaths affected strongly by spontaneous breathing efforts or artifacts. Then, we performed a virtual extrapolation of the flow-time waveform when the end-inspiratory flow was not zero, to allow for the calculation of C qstat ) under pressure control ventilation mode without the inspiratory pause maneuver. First, a screening strategy was applied to filter out breaths affected strongly by spontaneous breathing efforts or artifacts. Then, we performed a virtual extrapolation of the flow-time waveform when the end-inspiratory flow was not zero, to allow for the calculation of C qstat for each kept cycle. Finally, the output C qstat was obtained as the average of the smallest 40 C qstat measurements. The proposed method was validated against the gold standard C stat measured from real clinical settings and compared with two reported algorithms. The gold standard C stat was obtained by applying an end-inspiratory pause maneuver in the volume-control ventilation mode. Main results . Sixty-nine measurements from 36 patients were analyzed. The Bland-Altman analysis showed that the bias of agreement for C qstat versus the gold standard measurement was -0.267 ml/cmH 2 O (95% limits of agreement was -4.279 to 4.844 ml/cmH 2 O). The linear regression analysis indicated a strong correlation ( R 2  = 0.90) between the C qstat and gold standard. Significance . The results showed that the C qstat can be accurately estimated from continuous ventilator waveforms, including spontaneous breathing without an inspiratory pause maneuver. This method promises to provide continuous measurements compliant with mechanical ventilation., (© 2021 Institute of Physics and Engineering in Medicine.)

Objective: To evaluate pressure control ventilation (PCV) delivered through a minitracheotomy in treating severe flail chest trauma.Design: Case report.Setting: Intensive care unit of a trauma center.Patient: A 34-year-old woman affected by flail chest trauma and acute respiratory failure, who was initially treated with tracheal intubation to obtain internal pneumatic stabilization. The patient failed extubation and noninvasive mask treatment (pressure support ventilation plus PEEP) due to poor chestwall mechanics.Interventions: Minitracheotomy was performed and ventilation was achieved with high levels of inspiratory pressure (PCV or assisted PCV) to overcome the resistance of the cannula (Mini-Trach II, Portex, ID 4 mm). Esophageal and carinal pressures were monitored. Ventilatory treatment was always performed with the full cooperation of the patient; the patient's glottic function was always intact. The patient was successfully treated with pressure control ventilation delivered through the Mini-Trach. After 7 days of PCV, the patient was switched to assisted PCV. On the 20th day after admission, she was weaned from mechanical ventilation.Conclusions: We conclude that a suitable gas exchange and pneumatic stabilization in a flail chest condition can be achieved using minitracheostomic ventilation. At the same time, this treatment could reduce some side effects of traditional tracheal intubation. [ABSTRACT FROM AUTHOR]

Pressure controlled ventilation is a common mode of ventilation used to manage both adult and pediatric populations. However, there is very little evidence that distinguishes the efficacy of pressure controlled ventilation over that of volume controlled ventilation in the adult population. This gap in the literature may be due to the absence of a consistent and systematic algorithm for managing pressure controlled ventilation. This article provides a brief overview of the applications of both pressure controlled ventilation and volume controlled ventilation and proposes an algorithmic approach to the management of patients receiving pressure controlled ventilation. This algorithmic approach highlights the need for clinicians to have a comprehensive conceptual understanding of mechanical ventilation, pulmonary physiology, and interpretation of ventilator graphics in order to best care for patients receiving pressure controlled ventilation. The objective of identifying a systematic approach to managing pressure controlled ventilation is to provide a more generalizable and equitable approach to management of the ICU patient. Ideally, a consistent approach to managing pressure controlled ventilation in the adult population will glean more reliable information regarding actual patient outcomes, as well as the efficacy of pressure controlled ventilation when compared to volume controlled ventilation., (Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: We hypothesized that pressure control ventilation allows a more even distribution in the lung and better maintenance of the mean airway pressure than is achieved with volume control ventilation. We try to compare the effect of pressure control ventilation (PC) with that of volume control ventilation without an end-inspiratory pause (VC) during one-lung ventilation (OLV) in an anesthetized, paralyzed patient for performing thoracopic bullectomy of the lung., Methods: We ventilated 20 patients with VC and PC after the insertion of a thoracoscope in continual order for, at least for 15 minutes, for each, VC and PC procedure. At the end of VC and PC, the respiratory mechanics, gasometrics, and hemodynamic parameters were measured and collected., Results: We found no significant differences between VC and PC except for the peak inspiratory airway pressure (PIP), the mean airway pressure and the arterial oxygen partial pressure (PaO2). The PIP was significantly decreased from 27.0 +/- 6.0 cmH2O (VC) to 21.8 +/- 5.4 cmH2O (PC). The mean airway pressure was significantly increased from 8.6 +/- 1.6 cmH2O (VC) to 9.4 +/- 2.0 cmH2O (PC), and the PaO2 was significantly increased from 252.9 +/- 97.3 mmHg (VC) to 285.2 +/- 103.8 mmHg (PC)., Conclusions: If PC allows mechanical ventilation with the same tidal volume and respiratory rate as VC during OLV, then PC significantly increases the PaO2 but this is not clinically significant, and the PC significantly decreases the PIP, which induces barotrauma or volutrauma when the PIP is excessively high.