Esophageal Pressure Research Articles

The impact of a lung-protective ventilation mode using transpulmonary driving pressure titrated positive end-expiratory pressure on the prognosis of patients with acute respiratory distress syndrome.

This study aimed to assess the impact of a lung-protective ventilation strategy utilizing transpulmonary driving pressure titrated positive end-expiratory pressure (PEEP) on the prognosis [mechanical ventilation duration, hospital stay, 28-day mortality rate and incidence of ventilator-associated pneumonia (VAP), survival outcome] of patients with Acute Respiratory Distress Syndrome (ARDS). A total of 105 ARDS patients were randomly assigned to either the control group (n = 51) or the study group (n = 53). The control group received PEEP titration based on tidal volume [A tidal volume of 6 mL/kg, flow rate of 30-60L/min, frequency of 16-20 breaths/min, constant flow rate, inspiratory-to-expiratory ratio of 1:1 to 1:1.5, and a plateau pressure ≤ 30-35 cmH2O. PEEP was adjusted to maintain oxygen saturation (SaO2) at or above 90%, taking into account blood pressure], while the study group received PEEP titration based on transpulmonary driving pressure (Esophageal pressure was measured as a surrogate for pleural pressure using an esophageal pressure measurement catheter connected to the ventilator. Tidal volume and PEEP were adjusted based on the observed end-inspiratory and end-expiratory transpulmonary pressures, aiming to maintain a transpulmonary driving pressure below 15 cmH2O during mechanical ventilation. Adjustments were made 2-4 times per day). Statistical analysis and comparison were conducted on lung function indicators [oxygenation index (OI), arterial oxygen tension (PaO2), arterial carbon dioxide tension (PaCO2)] as well as other measures such as heart rate, mean arterial pressure, and central venous pressure in two groups of patients after 48h of mechanical ventilation. The 28-day mortality rate, duration of mechanical ventilation, length of hospital stay, and ventilator-associated pneumonia (VAP) incidence were compared between the two groups. A 60-day follow-up was performed to record the survival status of the patients. In the control group, the mean age was (55.55 ± 10.51) years, with 33 females and 18 males. The pre-ICU hospital stay was (32.56 ± 9.89) hours. The mean Acute Physiology and Chronic Health Evaluation (APACHE) II score was (19.08 ± 4.67), and the mean Murray Acute Lung Injury score was (4.31 ± 0.94). In the study group, the mean age was (57.33 ± 12.21) years, with 29 females and 25 males. The pre-ICU hospital stay was (33.42 ± 10.75) hours. The mean APACHE II score was (20.23 ± 5.00), and the mean Murray Acute Lung Injury score was (4.45 ± 0.88). They presented a homogeneous profile (all P > 0.05). Following intervention, significant improvements were observed in PaO2 and OI compared to pre-intervention values. The study group exhibited significantly higher PaO2 and OI compared to the control group, with statistically significant differences (all P < 0.05). After intervention, the study group exhibited a significant increase in PaCO2 (43.69 ± 6.71 mmHg) compared to pre-intervention levels (34.19 ± 5.39 mmHg). The study group's PaCO2 was higher than the control group (42.15 ± 7.25 mmHg), but the difference was not statistically significant (P > 0.05). There were no significant differences in hemodynamic indicators between the two groups post-intervention (all P > 0.05). The study group demonstrated significantly shorter mechanical ventilation duration and hospital stay, while 28-day mortality rate and incidence of ventilator-associated pneumonia (VAP) showed no significant differences. Kaplan-Meier survival analysis revealed a significantly better survival outcome in the study group at the 60-day follow-up (HR = 0.565, 95% CI: 0.320-0.999). Lung-protective mechanical ventilation using transpulmonary driving pressure titrated PEEP effectively improves lung function, reduces mechanical ventilation duration and hospital stay, and enhances survival outcomes in patients with ARDS. However, further study is needed to facilitate the wider adoption of this approach.

Comprehensive analysis of nutritional parameters in patients with idiopathic achalasia: A prospective study in India.

Achalasia cardia, a primary motility disorder of the esophagus, poses significant malnutrition risks. This study aims at comprehensively assessing the nutritional status in untreated achalasia patients, contrasting it with functional gastrointestinal disorders (FGIDs) cases and impact of per-oral endoscopic myotomy (POEM) on nutrition at one-year. We conducted a prospective study, including consecutive achalasia cases, from December 2021 to April 2022 at a tertiary care centre. Biochemical parameters, anthropometry, subjective global assessment (SGA) and malnutrition universal screening tool were used for nutritional assessment. Cases diagnosed with FGIDs served as controls. As many as118 cases (41.2 ± 13.9years, 61% males) with achalasia and 200 controls (43.4 ± 11.9years, 69% males) were included in the study. Sub-types of achalasia included type I (16.9%), II (76.3%) and III (6.8%). Overall, 38.1% and 6.8% cases were moderately and severely malnourished, respectively. As compared to controls, cases with achalasia had lower pre-albumin (19.4 vs. 25.2; p = 0.001), serum calcium (p = 0.012), vitamin D (p = 0.001), serum iron (p = 0.001), triceps fold thickness (p = 0.002) and hand-grip strength (p = 0.001). On univariate analysis, type-I achalasia, body mass index, % weight loss, lower esophageal sphincter pressures and Eckardt scores were predictors of malnourishment (SGA). On multivariate analysis, type of achalasia, mid arm circumference and low body mass index were significant predictors of malnourishment in cases with achalasia. There was significant improvement in the nutritional status after POEM at one-year follow-up. Achalasia patients demonstrate a notably higher risk of malnutrition compared to individuals with FGIDs. Nutritional status significantly improves after POEM. (NCT05161923).

Efficacy and Safety of "Vacuum Swallowing" Based on a Strong Negative Esophageal Pressure in Healthy Individuals.

Vacuum swallowing is a unique method for improving the pharyngeal passage of a bolus by creating subatmospheric negative pressure in the esophagus. However, whether healthy individuals and other patients with dysphagia can reproduce vacuum swallowing remains unclear. Therefore, this study aimed to assess whether healthy individuals verified using high-resolution manometry (HRM) could reproduce vacuum swallowing and evaluate its safety using a swallowing and breathing monitoring system (SBMS). Two healthy individuals who mastered vacuum swallowing taught this method to 12 healthy individuals, who performed normal and vacuum swallowing with 5 mL of water five times each. The minimum esophageal pressure and the maximum pressure of the lower esophageal sphincter (LES) were evaluated during each swallow using the HRM. Additionally, respiratory-swallowing coordination was evaluated using the SBMS. Ten individuals reproduced vacuum swallowing, and a total of 50 vacuum swallows were analyzed. The minimum esophageal pressure (-15.0 ± 4.9 vs. -46.6 ± 16.7 mmHg; P < 0.001) was significantly lower, and the maximum pressure of the LES (25.4 ± 37.7 vs. 159.5 ± 83.6 mmHg; P < 0.001) was significantly higher during vacuum swallowing. The frequencies of the I-SW and SW-I patterns in vacuum swallowing were 38.9% and 0%, respectively, using the SBMS. Vacuum swallowing could be reproduced safely in healthy participants with instruction. Therefore, instructing exhalation before and after vacuum swallowing is recommended to prevent aspiration.

Phrenic Ampulla Emptying Dysfunction in Patients with Esophageal Symptoms.

Pharyngeal pump, esophageal peristalsis, and phrenic ampulla emptying play important roles in the propulsion of bolus from the mouth to the stomach. There is limited information available on the mechanism of normal and abnormal phrenic ampulla emptying. The goal of our study is to describe the relationship between bolus flow and esophageal pressure profiles during the phrenic ampulla emptying in normal subjects and patient with phrenic ampulla dysfunction. Pressure (using topography) and bolus flow (using changes in impedance) relationship through the esophagus and phrenic ampulla were determined in 15 normal subjects and 15 patients with retrograde escape of bolus from the phrenic ampulla into esophagus during primary peristalsis. During the phrenic ampulla phase, 2 high pressure peaks (proximal, related to lower esophageal sphincter and distal, related to crural diaphragm) were observed in normal subjects and patients during the phrenic ampulla emptying phase. The proximal was always higher than the distal one in normal subjects; in contrast, reverse was the case in patients with the retrograde escape of bolus from the phrenic ampulla into the esophagus. We propose that a strong after-contraction of the lower esophageal sphincter plays an important role in the normal phrenic ampullary emptying. A defective lower esophageal after-contraction, along with high crural diaphragm pressure are responsible for the phrenic ampulla emptying dysfunction.

Physiological effects and safety of bed verticalization in patients with acute respiratory distress syndrome

BackgroundTrunk inclination in patients with Acute Respiratory Distress Syndrome (ARDS) in the supine position has gained scientific interest due to its effects on respiratory physiology, including mechanics, oxygenation, ventilation distribution, and efficiency. Changing from flat supine to semi-recumbent increases driving pressure due to decreased respiratory system compliance. Positional adjustments also deteriorate ventilatory efficiency for CO2 removal, particularly in COVID-19-associated ARDS (C-ARDS), indicating likely lung parenchyma overdistension. Tilting the trunk reduces chest wall compliance and, to a lesser extent, lung compliance and transpulmonary driving pressure, with significant hemodynamic and gas exchange implications.MethodsA prospective, pilot physiological study was conducted on early ARDS patients in two ICUs at CHU Clermont-Ferrand, France. The protocol involved 30-min step gradual verticalization from a 30° semi-seated position (baseline) to different levels of inclination (0°, 30°, 60°, and 90°), before returning to the baseline position. Measurements included tidal volume, positive end-expiratory pressure (PEEP), esophageal pressures, and pulmonary artery catheter data. The primary endpoint was the variation in transpulmonary driving pressure through the verticalization procedure.ResultsFrom May 2020 through January 2021, 30 patients were included. Transpulmonary driving pressure increased slightly from baseline (median and interquartile range [IQR], 9 [5–11] cmH2O) to the 90° position (10 [7–14] cmH2O; P < 10–2 for the overall effect of position in mixed model). End-expiratory lung volume increased with verticalization, in parallel to decreases in alveolar strain and increased arterial oxygenation. Verticalization was associated with decreased cardiac output and stroke volume, and increased norepinephrine doses and serum lactate levels, prompting interruption of the procedure in two patients. There were no other adverse events such as falls or equipment accidental removals.ConclusionsVerticalization to 90° is feasible in ARDS patients, improving EELV and oxygenation up to 30°, likely due to alveolar recruitment and blood flow redistribution. However, there is a risk of overdistension and hemodynamic instability beyond 30°, necessitating individualized bed angles based on clinical situations.Trial registration ClinicalTrials.gov registration number NCT04371016, April 24, 2020.

Use of pressure muscle index to guide pressure support ventilation setting: a study protocol and statistical plan for a prospective randomised controlled proof-of-concept trial

IntroductionAlthough pressure support ventilation is one of the most commonly used assisted ventilation modes in intensive care units, there is still a lack of precise strategies for setting pressure support....

The effectiveness and safety of the anti gastroesophageal reflux system in the treatment of gastroesophageal reflux disease: a single center study of 23 cases

Objective: To evaluate the safety and efficacy of domestically produced magnetic sphincter augmentation (MSA) for gastroesophageal reflux disease. Method: This study is a prospective cohort study. Patients with typical heartburn and reflux symptoms (at least partial response to proton pump inhibitors), abnormal esophageal acid exposure and normal esophageal peristalsis were included, prospectively in the Department of Gastroesophageal Surgery, Rocket Force Characteristic Medical Center from June 2019 to September 2022. Patients with hiatal hernia >2 cm and severe esophagitis were excluded. The MSA was wrapped around the distal esophagus after esophageal hiatus repair by laparoscopy. A postoperative questionnaire survey was conducted to assess the relief of symptom, complications, the discontinuation rate of proton pump inhibitor, and surgical satisfaction. Gastroscopy, high-resolution esophageal pressure measurement, and pH value impedance monitoring were also reviewed. The pre- and postoperative rates were compared using the McNeinar χ2 test. Result: Currently, 23 patients with gastroesophageal reflux disease were enrolled and underwent MSA surgery. There were 20 males and 3 females, aged (M (IQR)) 48 (14) years (range: 25 to 64 years). All cases were successfully implanted with MSA. Subjective indicators were followed for 17 (18) months (range: 14 to 53 months), while objective indicators were followed for 17 (1) months (range: 12 to 23 months). The postoperative gastrointestinal and extraesophageal symptom scores showed a significant decrease compared to preoperative levels as follows: the degree of subjective relief of overall digestive symptoms was 90 (20)% (range:0~100%), the degree of subjective relief of overall respiratory symptoms was 100(10)% (range: 10%~100%), the overall satisfaction rate was 83% (19/23), the proton pump inhibitor discontinuation rate was 70% (16/23). The proportion of esophagitis has decreased from 44% (10/23) to 9% (2/23) (κ=0.169, P=0.039), The Hill grade of gastroesophageal valve morphology improved from 1 case of grade Ⅰ, 5 cases of grade Ⅱ, 10 cases of grade Ⅲ, and 7 cases of grade Ⅲ preoperative to 22, 1, 0, and 0 cases postoperative. The proportion of lower esophageal sphincter pressure below normal has decreased from 70% (16/23) to 35% (8/23) (κ=0.170, P=0.012). There were 21 patients who restored normal esophageal acid exposure. Eleven patients had mild long-term dysphagia, but it didn't affect their daily life. No postoperative device migration, erosion, or secondary surgical removal occurred. Conclusions: Laparoscopic implantation of the MSA device was safe and well tolerated. It can effectively control the symptoms of gastroesophageal reflux disease, reduce medication, restore normal cardia morphology and function, and esophageal acid exposure. The main postoperative complication was dysphagia, but it was relatively mild.

Airway mechanics alters generation of cough motor pattern.

Effects of sequential increase in airway resistance: no, low (5 kPa.s/l), high (24 kPa.s/l), and complete block in the inspiratory or expiratory phase of mechanically induced cough on the cough motor pattern were studied in 16 anesthetized (pentobarbital) spontaneously breathing cats (3.70±0.15 kg, 11♂, 5♀). Esophageal pressure and electromyographic activities of the diaphragm during inspiration and abdominal muscles during expiration were analyzed. No significant changes in the number of coughs occurred. Inspiratory occlusion caused a prolongation of cough inspiratory phase, cough inspiratory diaphragm activity, and all cough-related activity. Inspiratory occlusion along with high resistance increased inspiratory esophageal pressure amplitude, total cough cycle duration and the time between maximum activity of the diaphragm and abdominal muscles. High expiratory resistance and occlusion resulted in increased cough expiratory esophageal pressure amplitude, a longer active portion of cough expiration, and cough abdominal activity. Expiratory occlusion also prolonged cough expiratory phase, all cough activity, and total cough cycle. Significantly increased airway resistance and occlusion induce secondary, in addition to mechanical, changes in cough by significantly modulating the generated cough motor pattern. A certain level of resistance appears to be successfully compensated, resulting in minimal changes in coughing characteristics, including expiratory airflow and the rising time of the airflow. Afferent feedback from the respiratory tract, particularly volume feedback, represents a significant factor in modulating cough, mainly under various pathological conditions in the respiratory system.

Manometric Abnormalities in Patients With and Without Chronic Cough

PurposeThis study examines the relationship between chronic cough and vagal hypersensitivity by measuring baseline esophageal motility, with interest in the upper esophageal sphincter (UES). Materials and methodsPatients undergoing workup for dysphagia were assigned to a chronic cough or control group based on self-reported symptoms. Differences in demographics, medical comorbidities, and high resolution esophageal manometry findings were obtained retrospectively. Results62.5% of our cohort had chronic cough (30/48). There were no significant differences between the two groups with respect to sex, age, and race/ethnicity. Laryngopharyngeal reflux (LPR) was the only statistically significant predictor of CC (OR 74.04, p = 0.010). Cough patients had upper esophageal sphincter relaxation duration (734 ms) significantly longer than the non-cough patients (582 ms; p = 0.03), though both groups had similar upper esophageal mean basal pressure, mean residual pressure, relaxation time-to-nadir, and recovery time. No significant difference was found in the median intrabolus pressure and UES motility mean peak pressure between groups. ConclusionSubtle differences in high-resolution manometry between patients with and without cough suggest, in line with previous studies, baseline alterations of upper esophageal function may manifest in patients with chronic cough through an undetermined mechanism that may include underlying vagal hypersensitivity. These findings encourage further manometric study examining the relationship between UES dysfunction and chronic cough.

Feasibility of synchronized high flow nasal cannula.

A high-flow nasal cannula (cHFNC) delivers flow continuously (during inspiration and expiration). Using the diaphragm electrical activity (Edi), synchronizing HFNC could be an alternative (cycling high/low flow on inspiration/expiration, respectively). The objective of this study was to demonstrate the feasibility of synchronized HFNC (sHFNC) and compare it to cHFNC. Different levels of cHFNC and sHFNC (4, 6, 8, and 10 liters per minute [LPM], with 2 LPM on expiration for sHFNC) were compared in eight rabbits (mean weight 3.16 kg), before and after acute lung injury (pre-ALI and post-ALI). Edi, tracheal pressure (Ptr), esophageal pressure (Pes), flow, and arterial CO2 were measured. In addition to the animal study, one 3.52 kg infant received sHFNC and cHFNC using a Servo-U ventilator. In the animal study, there were more pronounced decreases in Edi, reduced Pes swings and reduced PaCO2 at comparable flows during sHFNC compared to cHFNC both pre and post-ALI (p < .05). Baseline (pre-inspiratory) Ptr was 2-7 cmH2O greater during cHFNC (p < .05) indicating more dynamic hyperinflation. In one infant, the ventilator performed as expected, delivering Edi-synchronized high/low flow. Synchronizing high flow unloaded breathing, decreased Edi, and reduced PaCO2 in an animal model and is feasible in infants.

A correlation of computed tomographic esophageal hiatal cross-sectional surface area between brachycephalic and nonbrachycephalic cats.

In humans and dogs, especially brachycephalics, enlargement of the esophageal hiatus and insufficiency have been correlated with decreased lower esophageal sphincter pressure and increased frequency of gastroesophageal reflux. In cats, it has been suggested that gastroesophageal reflux occurs frequently with upper airway obstruction, including brachycephalics. Therefore, the purpose of the study was to determine whether the esophageal hiatal cross-sectional surface area (EH-CSA) differs between brachycephalic and nonbrachycephalic cats. Clinical records and CT images of cats that underwent thoracic, abdominal, and entire skull CT at multiple centers between January 2015 and September 2022 were retrospectively reviewed. Esophageal hiatal parameters (EH-CSA, EH-long axis diameter, and EH-short axis diameter) and craniometric indices (cranial index, skull index, and facial index) were measured by using multiplanar reconstruction, and the correlation of craniometry with EH-CSA was investigated. Ninety-eight cats (group 1: 42 brachycephalic cats and group 2: 56 nonbrachycephalic cats) were included. Esophageal hiatal cross-sectional surface area in brachycephalic cats was significantly larger than that in nonbrachycephalic cats. The EH-CSA significantly increased with the craniometric indices tending to increase with brachycephalism. The present study contributes to the veterinary literature by providing the EH-CSA as anatomical evidence that could likely correlate to gastroesophageal reflux predisposition in brachycephalic cats.

Oesophageal pressure topographic metrics in refractory gastroesophageal reflux disease: An Indian perspective

Oesophageal pressure topographic metrics in refractory gastroesophageal reflux disease: An Indian perspective

The Effect of Positive End-Expiratory Pressure on Pulmonary Vascular Resistance Depends on Lung Recruitability in Patients with Acute Respiratory Distress Syndrome.

Rationale: A U-shaped relationship should exist between lung volume and pulmonary vascular resistance (PVR), with minimal PVR at FRC. Thus, positive end-expiratory pressure (PEEP) in patients with acute respiratory distress syndrome (ARDS) should increase PVR if it induces significant lung distension compared with recruitment. However, this has never been proved in patients. Objectives: To study the effects of PEEP on PVR according to lung recruitability, evaluated by the recruitment-to-inflation (R/I) ratio. Methods: In patients with ARDS, we measured hemodynamic (pulmonary artery catheter), echocardiographic, and ventilatory variables (including esophageal pressure) at both low PEEP and higher PEEP by 10 cm H2O. Preload responsiveness was assessed by the passive leg-raising test at high PEEP. Measurements and Main Results: We enrolled 23 patients, including 10 low recruiters (R/I <0.5) and 13 high recruiters (R/I ⩾0.5). Raising PEEP from 4 (2-5) to 14 (12-15) cm H2O increased PVR in low recruiters (from 160 [120-297] to 243 [166-380] dyn·s/cm5; P < 0.01), whereas PVR was unchanged in high recruiters (from 224 [185-289] to 235 [168-300] dyn·s/cm5; P = 0.55). Right-to-left ventricular end-diastolic area ratio simultaneously increased in low recruiters (from 0.54 [0.50-0.59] to 0.64 [0.56-0.70]; P < 0.01) while remaining stable in high recruiters (from 0.70 [0.65-0.79] to 0.68 [0.58-0.80]; P = 0.48). Raising PEEP decreased cardiac index only in preload responsive patients. Conclusions: PEEP increases PVR only when it induces significant lung distension compared with recruitment according to the R/I ratio. Tailoring PEEP on this recruitability index should mitigate its hemodynamic effects.

Difficulties in Extracting Dentures Stuck in The Esophagus

Foreign bodies in the esophagus are one of the common problems that ENT doctors often face. One of them is a foreign body with dentures in the esophagus. The diagnosis of a foreign body of dentures in the esophagus is established based on anamnesis, physical examination, radiological examination, and esophagoscopy. The act of esophagoscopy is performed as diagnostic and therapeutic. If not handled immediately and adequately, foreign bodies in the esophagus can cause complications such as esophageal perforation, blockage, and pressure of the foreign body into the airway and other complications. Patient readiness, availability of tools, and the presence of experienced experts are significant factors in overcoming this case. Prompt treatment using esophagoscopy is a safe and effective way to perform foreign body extraction in most cases. Thoracotomy to esophagectomy is performed in cases of foreign bodies in the esophagus that experience difficulties or failure in extracting by esophagoscopy. It was reported that two cases of foreign bodies with dentures in the esophagus were removed by thoracotomy accompanied by esophagectomy.

Correlation of diaphragm thickening fraction and oesophageal pressure swing in non-invasive ventilation of healthy subjects

IntroductionThe diaphragm thickening fraction (DTF) may be a valuable tool for estimating respiratory effort in non-invasive ventilation. The primary aim of this physiological study is the investigation of the correlation of DTF with oesophageal pressure swings (ΔPoes). A secondary aim is to assess the discriminatory capacity of the index tests for different exercise loads.MethodsHealthy volunteers underwent spontaneous breathing and non-invasive ventilation with a sequence of different respirator settings. The first sequence was carried out at rest. The same sequence was repeated twice, with additional ergometry of 25 and 50 Watts, respectively. DTF and ΔPoes were measured during each ventilation configuration.Results23 individuals agreed to participate. DTF was moderately correlated with ΔPoes (repeated measures correlation ρ = 0.410, p < 0.001). Both ΔPoes and DTF increased consistently with exercise loading in every ventilation configuration, however ΔPoes showed greater discriminatory capacity.ConclusionDTF was moderately correlated with ΔPoes and could discriminate reasonably between exercise loads in a small cohort of non-invasively ventilated healthy subjects. While it may not accurately reflect the absolute respiratory effort, DTF might help titrating individual non-invasive respiratory support. Further investigations are needed to test this hypothesis.Trial RegistrationThis study was not prospectively registered.

Mechanical ventilation in a conscious male during exercise: a case report.

We recently explored the cardiopulmonary interactions during partial unloading of the respiratory muscles during exercise. Expanding upon this work, we present a noteworthy case study whereby we eliminated the influence of respiration on cardiac function in a conscious but mechanically ventilated human during exercise. This human was a young healthy endurance-trained male who was mechanically ventilated during semi-recumbent cycle exercise at 75 Watts (W) (∼30% Wmax). During mechanically ventilated exercise, esophageal pressure was reduced to levels indistinguishable from the cardiac artefact which led to a 94% reduction in the power of breathing. The reduction in respiratory pressures and respiratory muscle work led to a decrease in cardiac output (-6%), which was due to a reduction in stroke volume (-13%), left ventricular end-diastolic volume (-15%), and left-ventricular end-systolic volume (-17%) that was not compensated for by heart rate. Our case highlights the influence of extreme mechanical ventilation on cardiac function while noting the possible presence of a maximal physiological limit to which respiration (and its associated pressures) impacts cardiac function when the power of breathing is maximally reduced.

Investigating the Esophageal Pressure Measurement to Adjust NIPPV to Prevent Pulmonary Barotrauma in Patients with COVID- 19 under Respiratory Support Admitted to the ICU

Background: Respiratory failure following COVID-19 can lead to the death of COVID patients. Monitoring these patients during their ventilation is essential. The present study investigated the effect of measuring esophageal pressure in preventing barotrauma while receiving Noninvasive Positive Pressure Ventilation (NIPPV) in patients with COVID-19. Methods: The present study is a single-blind clinical trial conducted on patients with COVID-19 hospitalized in the Intensive Care Unit (ICU). The patients were divided into two groups; one group had their esophageal pressure measured while receiving NIPPV, their ventilation was adjusted based on this pressure, and the second group was only ventilated according to anesthesia protocols. Finally, the data was entered into SPSS V.23 software and analyzed according to the study’s objectives. Results: The results of the present study showed that the incidence of subcutaneous emphysema-type barotrauma in the Esophageal Pressure (EP) monitoring group was lower than in the non-Esophageal Pressure (nEP) monitoring group. Also, the IPAP level in the EP group was lower than in NEP. The incidence of complications such as abdominal bloating and gavage intolerance was lower in EP than in NEP. The blood oxygen level in NEP was higher than in EP, but there was no significant difference between them. Conclusion: Esophageal pressure measurement in patients with COVID-19 receiving NIPPV can reduce barotrauma in the patients.

The Relationship of Diaphragmatic Ultrasound-Based and Manometric Indices With Difficult Weaning in Tracheostomized Patients.

Patients with a tracheostomy and difficult weaning from invasive mechanical ventilation constitute a challenging problem in critical care. An increased duration of ventilation may lead to diaphragmatic dysfunction and a noninvasive assessment of the diaphragm, such as ultrasound, attracts interest in the clinical practice. We evaluated the relationship of ultrasound-derived indices with weaning outcome and with established indices of respiratory strength and load in subjects who are tracheostomized and undergoing weaning. This prospective study was conducted at an academic ICU in Greece. Twenty subjects with tracheostomy and difficult weaning, during a spontaneous breathing trial, underwent time synchronous diaphragmatic sonography and esophageal manometry, to assess diaphragmatic excursion and thickening fraction, esophageal and transdiaphragmatic pressures, pressure-time product of the esophageal pressure, and maximum inspiratory pressure. The primary outcome was liberation from mechanical ventilation at 48 h. The relationship of diaphragmatic ultrasound with esophageal pressure-derived indices was also evaluated. Weaning from invasive ventilation failed in 10 subjects. Diaphragmatic excursion exhibited a significant difference between weaning success and failure (1.34 ± 0.56 versus 0.79 ± 0.44; P = .044), a strong correlation with transdiaphragmatic pressure (r = 0.7, P = .02), and a moderate correlation with the pressure-time product of the esophageal pressure (r = 0.65, P = .02) and the maximum inspiratory pressure (r = 0.66, P = .02). Transdiaphragmatic pressure presented the highest area under the curve (0.97). However, when transdiaphragmatic pressure was compared with diaphragmatic excursion (area under the curve, 0.84) for predictive accuracy, no significant difference was found. Diaphragmatic excursion is a valuable tool for the assessment of diaphragmatic strength, respiratory load, and weaning prediction.

Respiratory and chest wall mechanics in very preterm infants.

Data on static compliance of the chest wall (Ccw) in preterm infants are scarce. We characterized the static compliance of the lung (CL) and Ccw to determine their relative contribution to static compliance of the respiratory system (Crs) in very preterm infants at 36 wk postmenstrual age (PMA). We also aimed to investigate how these compliances were influenced by the presence of bronchopulmonary dysplasia (BPD) and impacted breathing variables. Airway opening pressure, esophageal pressure, and tidal volume (VT) were measured simultaneously during a short apnea evoked by the Hering-Breuer reflex. We computed tidal breathing variables, airway resistance (R), and dynamic lung compliance (CL,dyn), inspiratory capacity (IC), and Crs, CL, and Ccw. Functional residual capacity was assessed by the multiple breath washout technique (FRCmbw). Breathing variables, compliances, and lung volumes were adjusted for body weight. Twenty-three preterm infants born at 27.2 ± 2.0 wk gestational age (GA) were studied at 36.6 ± 0.6 wk PMA. Median and interquartile range (IQR) Crs/kg is 0.69 (0.6), CL/kg 0.95 (1.0), and Ccw/kg 3.0 (2.4). Infants with BPD (n = 11) had lower Crs/kg (P = 0.013), CL/kg (P = 0.019), and Ccw/kg (P = 0.027) compared with infants without BPD. Ccw/CL ratio was equal between groups. FRCmbw/kg (P = 0.044) and IC/kg (P = 0.005) were decreased in infants with BPD. Infants with BPD have reduced static compliance of the respiratory system, the lungs, and chest wall. Decreased Crs, CL, and Ccw in infants with BPD explain the lower FRC and IC seen in these infants.NEW & NOTEWORTHY Data on chest wall compliance in very preterm infants in the postsurfactant era are scarce. To our knowledge, we are the first group to report data on static respiratory system compliance (Crs), lung compliance (CL), and chest wall compliance (Ccw) in preterm infants with and without bronchopulmonary dysplasia (BPD) in the postsurfactant era.

Analysis of the Correlation Between Dynamic Characteristics and Symptoms of Gastroesophageal Reflux Disease.

To investigate the esophageal motility characteristics of gastroesophageal reflux disease (GERD) and their relationship with symptoms. We examined 101 patients diagnosed with GERD by endoscopy and divided them into 3 groups as follows: nonerosive reflux disease (NERD), reflux esophagitis, and Barrett esophagus. Esophageal high-resolution manometry and the GERD Questionnaire were used to investigate the characteristics of esophageal dynamics and symptoms. In addition, the reflux symptom index was completed and the patients were divided into 7 groups according to symptoms. We then determined the correlation between dynamic esophageal characteristics and clinical symptoms. Upper (UES) and lower (LES) esophageal sphincter pressures and the 4-second integrated relaxation pressure in the RE group were lower than those in the NERD group. The 4-second integrated relaxation pressure in the Barrett esophagus group was also lower than that in the NERD group. In the analysis of extraesophageal symptoms, high-resolution manometry showed significant differences in UES pressures among all groups. Further subgroup analysis showed that compared with the group without extraesophageal symptoms, the UES pressure of the groups with pharyngeal foreign body sensation, throat clearing, and multiple extraesophageal symptoms was lower. As GERD severity increases, motor dysfunction of the LES and esophageal body gradually worsens, and the LES plays an important role in GERD development. Decreased UES pressure plays an important role in the occurrence of extraesophageal symptoms, which is more noticeable in patients with pharyngeal foreign body sensation and throat clearing.