Thickening Fraction Research Articles

Rapid Shallow Breathing Index and Ultrasonographic Diaphragmatic Parameters as Predictors of Weaning Outcome in Critically Ill Patients on Mechanical Ventilation.

Successful weaning is a crucial element in care toward critically ill patients on mechanical ventilation. An attempt was made to propose and assess a reliable predictor of weaning outcome. A prospective observational study was conducted on 76 patients on mechanical ventilation, assessed by Acute Physiology and Chronic Health Evaluation II (APACHE II) score. For all these patients we calculate Rapid shallow breathing index (RSBI), Ultrasonographic diaphragmatic parameters namely diaphragmatic excursion (DEx), diaphragmatic thickening fraction (DTF) and diaphragmatic contraction velocity (DCV). Values were compared among patients with two groups of successful and failed weaning outcomes, respectively, and statistically analyzed. Of 76 patients included in the study, with ultrasonographic diaphragmatic parameters being measured 30 min into SBT, 71 patients tolerated spontaneous breathing test (SBT) for 2 h and were extubated. Of these, 61 patients did not require reintubation or any form of ventilatory support within 48 h after extubation. There was a statistically significant difference in APACHE II scores, duration of ventilation, oxygen saturation levels, RSBI, DEx, DTF, and DCV between groups of patients who showed successful and failed weaning from mechanical ventilation. There were a significant positive correlation between the duration of ventilation and the RSBI and a significant negative correlation between DEx, DCV, DTF, and duration of ventilation. As predictors of weaning outcome, RSBI showed the best validity, followed by DCV, DTF, and DEx. RSBI can be reliably used as a predictor of weaning outcome in critically ill patients on mechanical ventilation.

Rehabilitation effects of acupuncture on the diaphragmatic dysfunction in respiratory insufficiency: A systematic review and meta-analysis

IntroductionMechanical ventilation after respiratory insufficiency can induce diaphragm dysfunction through various hypothesized mechanisms. In this study, we evaluated the rehabilitative effect of acupuncture on diaphragm function in patients with respiratory insufficiency using meta-analysis and summarised the rules of acupoints through association rules analysis. MethodsArticles (published from January 2000 to February 2024) were retrieved from the following databases: PubMed, Cochrane Library, Embase, Web of Science, CNKI, VIP, SinoMed, and Wanfang. Two researchers conducted literature selection, data extraction, and statistical analysis independently. The risk of bias was assessed utilizing the Physical Therapy Evidence Database (PEDro) scale. The meta-analysis was performed with RevMan 5.4 software, and the quality of each outcome evidence was assessed via the online software GRADEpro GDT. The regularity of acupoint selection was summarized using association rules analysis. This study is registered on PROSPERO, number CRD42024526705. ResultsEleven articles were eventually included, all of which were of low to moderate quality. Results of the meta-analysis showed a significant increase in diaphragmatic thickening fraction (MD 3.40 [1.52, 5.27]) and diaphragmatic excursion (MD 0.95 [0.58, 1.31]) in patients with respiratory insufficiency after acupuncture treatment. Also, OI (MD 28.52 [15.93, 41.11]) and PaO2 (MD 7.18 [2.22, 12.13]) were significantly elevated and PaCO2 (MD −6.94 [-12.30, −1.59]) was decreased. Mechanical ventilation time (MD-1.86 [-2.28, −1.45]) was also significantly improved. The overall quality of the outcome evidence is deemed moderate. Association rules analysis showed that ST36, RN4, RN6, and others are core acupoints for the treatment of diaphragmatic dysfunction in patients with respiratory insufficiency by acupuncture. ConclusionAcupuncture shows potential in the rehabilitation of patients with respiratory insufficiency and may serve as a complementary and alternative therapy for related conditions. We suggest the use of ST36 as a core acupoint, in combination with other acupoints. Due to the potential publication bias and high heterogeneity of the current data, further high-quality RCTs are needed to confirm these findings.

Effect of five different body positions on lung function in stroke patients with tracheotomy

ABSTRACT Background In stroke patients with tracheotomy, reduced lung function heightens pulmonary infection risk. Body position can affect lung function; however, its impact in stroke patients with tracheostomy remains unclear. Objective To investigate the influence of five body positions on pulmonary function in stroke patients with tracheotomy. Methods Pulmonary function was assessed in five body positions (supine, supine 30°, supine 60°, sitting, and prone) in 47 stroke patients who underwent tracheotomy. Diaphragmatic excursion during quiet breathing (DEQ), diaphragmatic thickening fraction during quiet breathing (DTFQ), and diaphragmatic excursion during coughing (DEC) were measured using ultrasound. Peak cough flow (PCF) was measured using an electronic peak flow meter. Results Different positions had a significant impact on DEQ, DEC, and PCF in stroke patients with tracheotomy, although not on DTFQ. DEQ showed no significant differences between supine 60°, sitting, and prone positions. Both DEC and PCF reached their maximum values in the sitting position. In the sub-group analysis, DEQ in females did not show significant differences across different positions. Both males and females exhibited significantly higher PCF in the sitting compared to supine position. The lung function of obese patients was significantly better in the sitting than in the supine and supine 30° position. Regardless of the patient’s level of consciousness and whether the brainstem was injured, lung function in the sitting position was significantly higher than in the supine position. Conclusions Body posture influences lung function in stroke patients with tracheotomy. Patients should adopt a sitting position to enhance pulmonary function.

Assessment of Diaphragmatic Dysfunction in Mechanically Ventilated Patients with Ultrasonography.

The reliability of the diaphragm thickening fraction in predicting weaning failure in mechanically ventilated patients in the intensive care unit (ICU), as well as the relationship between the patients' diaphragmatic inspiratory excursion and diaphragmatic thickness. Fifty mechanically ventilated patients participated in this hospital-based cross-sectional prospective study in a tertiary care teaching hospital. Patients who had been on a mechanical ventilator for at least 7 days and whose legal guardian was willing to provide consent were also included in the research. People with hemodynamic instability and those whose legal guardians were reluctant to comply were excluded. Using diaphragmatic thickening fraction as a diagnostic criterion, the weaning failure group consisted of 24 patients, out of which we predicted diaphragmatic dysfunction (DD) in 19 patients. The weaning success group consisted of 26 patients, of which we predicted no DD in 21 patients. Weaning success or failure was predicted by diaphragmatic thickening fraction with a sensitivity of 79.16% and a specificity of 80.76%, diaphragm excursion with a sensitivity of 70.8% and an 80.7%, and diaphragmatic thickness with a sensitivity of 66.66% and a specificity of 73.91%, respectively. Diagnosing DD in mechanically ventilated, figuring out if extubation would be effective or not, monitoring respiratory effort, and assessing atrophy in ICU patients, ultrasonography may be an effective and accurate technique for mechanical ventilation patients, and it provides a convenient, noninvasive, affordable, and secure way to assess DD.

Effects of cardiopulmonary rehabilitation on lung and respiratory muscle function of patients with post-COVID-19 syndrome: a controlled and randomized study

Purpose: Thus, this study aimed to evaluate the effects of cardiopulmonary rehabilitation on lung and respiratory muscle function of patients with post-COVID-19 syndrome. Patients and methods: We conducted a randomized controlled trial with 34 patients with post-COVID-19 syndrome (> 18 years) who were symptomatic for more than four weeks. The evaluators were blinded. Participants were randomized into two groups: cardiopulmonary rehabilitation group or biweekly lectures (control group) regarding health education. We assessed lung function (forced vital capacity [FVC], forced expiratory volume in the first second [FEV1], FEV1/FVC ratio, and peak expiratory flow [PEF]), respiratory muscle strength and endurance, diaphragmatic thickening fraction and mobility, and dyspnea (modified Borg scale). Results: The intervention improved FVC, FEV1, and PEF of patients after six weeks of rehabilitation. The rehabilitation group also showed lower dyspnea and respiratory muscle strength and endurance than the control group. Conclusion: The cardiopulmonary rehabilitation protocol improved lung and respiratory muscle function and reduced dyspnea in patients with post-COVID-19 syndrome.

The ratio of parasternal intercostal muscle-thickening fraction-to-diaphragm thickening fraction for predicting weaning failure

BackgroundDiaphragm dysfunction is associated with weaning outcomes in mechanical ventilation patients, in the case of diaphragm dysfunction, the accessory respiratory muscles would be recruited. The main purpose of this study is to explore the performance of parasternal intercostal muscle thickening fraction in relation to diaphragmatic thickening fraction ratio (TFic1/TFdi2) for predicting weaning outcomes, and compare its accuracy with D-RSBI in predicting weaning failure. Materials and methodsWe prospectively enrolled consecutive patients from 7/2022–5/2023. We measured TFic, TFdi, and diaphragmatic excursion (DE3) by ultrasound and calculated the TFic/TFdi ratio and diaphragmatic rapid shallow breathing index (D-RSBI4). Receiver-operator characteristic (ROC5) curves evaluated the accuracy of the TFic/TFdi ratio and D-RSBI in predicting weaning failure. Results161 were included in the final analysis, 114 patients (70.8%) were successfully weaned from mechanical ventilation. The TFic/TFdi ratio (AUROC = 0.887 (95% CI: 0.821–0.953)) was superior to the D-RSBI (AUROC = 0.875 (95% CI: 0.807–0.944)) for predicting weaning failure. ConclusionsThe TFic/TFdi ratio predicted weaning failure with high accuracy and outperformed the D-RSBI.

Ultrasound examination in assessing the functional state of the diaphragm in patients with respiratory failure requiring respiratory support

Diaphragm dysfunction (DD) is diagnosed in 60% patients 24 hours after intubation. Diaphragm ultrasound (DU) facilitates non-invasive assessment of excursion and thickness of the diaphragm throughout the breathing cycle. Sonographically measured excursion and thickening fraction (TF) of the diaphragm show moderate correlation with reference methods for diaphragm dysfunction detection. Both increase and decrease in diaphragm thickness in mechanically ventilated patients are associated with prolonged mechanical ventilation. TF exceeding 25% increases probability of successful weaning. Maintaining TF within 15–40 % might shorten the duration of mechanical ventilation.

Role of diaphragmatic ultrasound in predicting weaning success from mechanical ventilation in pediatric intensive care unit

BackgroundWeaning off mechanical ventilation (MV) is a critical step in pediatric ICU; however, it lacks standardized criteria. Diaphragmatic ultrasound parameters like diaphragm thickening fraction (DTF), diaphragmatic excursion (DE) and time to peak inspiratory amplitude (TPIA) can be used to assess diaphragmatic muscle strength and to predict weaning success.Aim of studyIs to assess the validity of diaphragmatic ultrasonography as a predictor of weaning outcome from mechanical ventilation in pediatric age group.MethodsProspective cohort study including 30 pediatric patients aged 0–18 years on mechanical ventilation. Ultrasound measurements of diaphragmatic thickening fraction, diaphragmatic excursion and time to peak inspiratory amplitude were taken during the spontaneous breathing trial (SBT) and compared between successful and failed weaning groups.ResultsOut of the included 30 patients (50% male), 19 patients (63.3%) were successfully weaned. Mechanical ventilation duration was significantly longer in the failed weaning group (P = 0.017). There was significant difference between both groups regarding right DE (P = 0.032) and left DE (P = 0.022) with cutoff values of > 4.1 mm and > 5.5 mm with AUC (Area under curve) of 0.737 and 0.831, respectively. There was no statistically significant difference between both groups regarding DTF or TPIA.ConclusionWe have found that DE is a predictor of weaning success, while DTF and diaphragmatic TPIA had no correlation with weaning outcome.

Diaphragmatic Ultrasound in Children With Asthma Exacerbations.

Asthma is a leading cause of pediatric emergency department visits, yet few tools exist to objectively measure asthma severity. Diaphragmatic ultrasound (DUS) is a novel method of assessing respiratory distress; however, data are lacking for children.Our primary aim was to determine if diaphragmatic excursion (DE), diaphragmatic thickening (DT), or diaphragmatic thickening fraction (TF) correlated with asthma severity as determined by the Pediatric Respiratory Assessment Measure (PRAM) score. Secondarily, we examined if these parameters correlated with need for respiratory support and evaluated interrater reliability. We conducted a prospective study of children 5-18 years presenting to a pediatric emergency department with an asthma exacerbation. Diaphragmatic ultrasound was performed by a trained pediatric emergency medicine sonologist in subcostal (DE) and midaxillary (DT). Thickening fraction was calculated from DT values as previously described in literature. To evaluate interrater reliability, a subset of subjects had DUS performed by a second sonologist. We enrolled 47 subjects for a total of 51 encounters. The mean age was 9.1 ± 3.7 years. Twenty-five (49%) had mild, 24 (47%) had moderate, and 2 (4%) had severe asthma. There was a significant difference in midaxillary DT and TF between children with mild and moderate asthma ( P = 0.02; mean difference, 0.2 mm; 95% confidence interval [CI], 0.03-0.4 and P = 0.02; mean difference, 0.11 mm; 95% CI, 0.02-0.2, respectively). No difference was found in subcostal DE ( P = 0.43; mean difference, 1.4 mm; 95% CI, -2.1 to 4.8). No association was found between use of positive pressure and DUS parameters. Fourteen encounters had 2 sonologists perform DUS, with strong interrater reliability found for midaxillary DT (Pearson correlation, 0.56) and poor association for subcostal DE (Pearson correlation, 0.18). In this pilot study, we conclude that DUS may be helpful in assessing severity of asthma. The midaxillary view assessment for DT and TF had the best correlation with asthma severity and the best interrater reliability. Future studies may benefit from focusing on the midaxillary view for DT and TF.

Diaphragm ultrasound in patients with prolonged weaning from mechanical ventilation.

Several publications have examined diaphragmatic ultrasound using two-dimensional (2D) parameters in the context of weaning from mechanical ventilation (MV) and extubation. However, the studied cohorts had rather short duration of ventilation. Examinations on patients with prolonged weaning after long-term ventilation were missing. It was the aim of this study to assess of the diaphragm and peripheral musculature of patients undergoing prolonged weaning creating a chronological sequence of ultrasonic parameters during the course of weaning. This study was carried out as a monocentric, prospective observational cross-sectional study. Patients in prolonged weaning who were transferred to a specialized weaning unit were eligible for inclusion if they were ventilated invasively by means of an endotracheal tube or tracheal cannula and if their expected treatment period was at least 5 days. Diaphragmatic function and one representative peripheral muscle were examined in 50 patients between March 2020 and April 2021. The 2D sonographic parameters of diaphragm and diaphragmatic function consisted of diaphragmatic thickness (Tdi) at the end of inspiration and expiration, the fractional thickening (FT) and the diaphragmatic excursion. Additionally, the M. quadriceps femoris was sonographically assessed at two locations. The difference of measurements between the first and the last measuring timepoint were examined using the Wilcoxon signed-rank test. For a longer chronological sequence, the Friedman's rank sum test with subsequent Wilcoxon-Nemenyi-McDonald-Thompson test for multiple comparisons was carried out. Fifty patients with prolonged weaning were included. The median duration of MV before transfer to the weaning unit was 11.5 [interquartile range (IQR) 10] days. Forty-one patients could be assessed over the full course of weaning, with 38 successfully weaned. Within these 41 patients, the sonographic parameters of the diaphragm slightly increased over the course of weaning indicating an increase in thickness and mobility. Especially parameters which represented an active movement reached statistical significance, i.e., inspiratory Tdi when assessed under spontaneous breathing [begin 3.41 (0.99) vs. end 3.43 (1.31) mm; P=0.01] and diaphragmatic excursion [begin 0.7 (0.8) vs. end 0.9 (0.6) cm; P=0.01]. The presence of positive end-expiratory pressure (PEEP) and pressure support did not influence the sonographic parameters significantly. The M. quadriceps femoris, in contrast, decreased slightly but constantly over the time [lower third: begin 1.36 (0.48) vs. end 1.28 (0.36) cm; P=0.054]. The present study is the first one to longitudinally analyse diaphragmatic ultrasound in patients with prolonged weaning. Sonographic assessment showed that Tdi and excursion increased over the course of prolonged weaning, while the diameter of a representative peripheral muscle decreased. However, the changes are rather small, and data show a wide dispersion. To allow a potential, standardized use of diaphragm ultrasound for diagnostic decision support in prolonged weaning, further studies in this specific patient group are required.

Intercostal Muscle Function During Noninvasive Ventilation and Acute Hypercapnic Respiratory Failure.

Noninvasive ventilation (NIV) is a widely used and well-established treatment modality for respiratory failure. In patients with increased respiratory work of breathing, accessory muscles are commonly activated along with the diaphragm. Whereas diaphragm ultrasound has been utilized to assess outcomes of mechanical ventilation, the data on intercostal muscle ultrasound remain limited. We aimed to investigate the association between intercostal muscle thickening fraction (TF) and NIV failure in critical care patients with hypercapnic respiratory failure. Critical care subjects receiving NIV for hypercapnic respiratory failure were enrolled in the study. The intercostal muscle TF was measured on admission day (day 0) and the following day (day 1). NIV failure was defined as the need for invasive mechanical ventilation or death during NIV therapy. A total of 158 subjects were enrolled, and 30 experienced NIV failure. Age, sex, and body mass index (BMI) were similar in the NIV success and failure groups. Acute Physiology And Chronic Health Evaluation II (APACHE II) and the Sequential Organ Failure Assessment (SOFA) scores were higher in the NIV failure group. In terms of causes of respiratory failure, the COPD exacerbation rate was higher in the NIV success group. TF was higher in the NIV failure group on both day 0 and day 1. The increased TF on the ICU admission day, with a cutoff value of 12%, was associated with NIV failure after adjusting for age, sex, BMI, APACHE II, and SOFA. Persistence of a higher TF value on both day 0 and day 1 was also associated with NIV failure risk. There was a positive relation between intercostal muscle TF measured by ultrasound and NIV failure, even after adjusting for APACHE II and SOFA scores.

Relationship Between Diaphragm Thickness, Thickening Fraction, Dome Excursion, and Respiratory Pressures in Healthy Subjects: An Ultrasound Study

PurposeDiaphragm ultrasonography is used to identify causes of diaphragm dysfunction. However, its correlation with pulmonary function tests, including maximal inspiratory (MIP) and expiratory pressures (MEP), remains unclear. This study investigated this relationship by measuring diaphragm thickness, thickening fraction (TF), and excursion (DE) using ultrasonography, and their relationship to MIP and MEP. It also examined the influence of age, sex, height, and BMI on these measures.MethodsWe recruited healthy Japanese volunteers and conducted pulmonary function tests and diaphragm ultrasonography in a seated position. Diaphragm ultrasonography was performed during quiet breathing (QB) and deep breathing (DB) to measure the diaphragm thickness, TF, and DE. A multivariate analysis was conducted, adjusting for age, sex, height, and BMI.ResultsBetween March 2022 and January 2023, 109 individuals (56 males) were included from three facilities. The mean (standard deviation) MIP and MEP [cmH2O] were 72.2 (24.6) and 96.9 (35.8), respectively. Thickness [mm] at the end of expiration was 1.7 (0.4), TF [%] was 50.0 (25.9) during QB and 110.7 (44.3) during DB, and DE [cm] was 1.7 (0.6) during QB and 4.4 (1.4) during DB. Multivariate analysis revealed that only DE (DB) had a statistically significant relationship with MIP and MEP (p = 0.021, p = 0.008). Sex, age, and BMI had a statistically significant influence on relationships between DE (DB) and MIP (p = 0.008, 0.048, and < 0.001, respectively).ConclusionIn healthy adults, DE (DB) has a relationship with MIP and MEP. Sex, age, and BMI, but not height, are influencing factors on this relationship.

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

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

Ultrasonographic changes and impact factors of diaphragmatic function in patients with obstructive sleep apnea-hypopnea syndrome.

Diaphragmatic impairment has been reported in obstructive sleep apnea-hypopnea syndrome (OSAHS) patients. However, the risk factors of diaphragmatic dysfunction are unclear. This study was conducted to evaluate the diaphragmatic function and to investigate impact factors of ultrasonographic changes of the diaphragm in OSAHS patients. This cross-sectional study recruited 150 snoring patients. All patients were divided into the control group (AHI < 5/h, n = 20), the mild-to-moderate OSAHS group (5/h ≤ AHI ≤ 30/h, n = 61), and the severe OSAHS group (AHI > 30/h, n = 69). Diaphragmatic thickness at function residual capacity (TFRC) and total lung capacity (TTLC) were measured by two-dimensional ultrasound, and the diaphragmatic excursion during tidal and deep breath was measured by M-mode ultrasound. The diaphragmatic thickening fraction (TF) was calculated. Spearman analysis and multiple linear stepwise regression analysis were conducted to analyze the impact factors of diaphragmatic function. TFRC in the control group, mild-to-moderate OSAHS group, and severe OSAHS group was 1.23 (1.10, 1.39) mm, 1.60 (1.43, 1.85) mm, and 1.90 (1.70, 2.25) mm; TTLC was 2.75 (2.53, 2.93) mm, 3.25 (2.90, 3.55) mm, and 3.60 (3.33, 3.90) mm, and TF was 119.23% (102.94, 155.97), 96.55% (74.34, 119.11), and 85.29% (60.68,101.22). There were across-group significant differences in TFRC, TTLC, and TF (P < 0.05). The oxygen desaturation index was the influencing factor of TFRC, TTLC, and TF (P < 0.05). The diaphragm is thickened and diaphragmatic contractility is decreased in OSAHS patients. Nocturnal intermittent hypoxia is a risk factor for diaphragmatic hypertrophy and impaired diaphragmatic contractility.

The effect of high-flow oxygen via tracheostomy on respiratory pattern and diaphragmatic function in patients with prolonged mechanical ventilation: A randomized, physiological, crossover study

BackgroundCompared to conventional oxygen devices, high-flow oxygen treatment (HFOT) through the nasal cannulae has demonstrated clinical benefits. Limited data exist on whether such effects are also present in HFOT through tracheostomy. Hence, we aimed to examine the short-term effects of HFOT through tracheostomy on diaphragmatic function and respiratory parameters in tracheostomized patients on prolonged mechanical ventilation. MethodsA randomized, crossover, physiological study was conducted in our ICU between December 2020 and April 2021, in patients with tracheostomy and prolonged mechanical ventilation. The patients underwent a 30-min spontaneous breathing trial (SBT) and received oxygen either via T-piece or by HFOT through tracheostomy, followed by a washout period of 15-min breathing through the T-piece and receipt of 30-min oxygen with the other modality in a randomized crossover manner. At the start and end of each session, blood gasses, breathing frequency (f), and tidal volume (VT) via a Wright's spirometer were measured, along with diaphragm ultrasonography including diaphragm excursion and diaphragmatic thickening fraction, which expressed the inspiratory muscle effort. ResultsEleven patients were enrolled in whom 19 sessions were uneventfully completed; eight patients were studied twice on two different days with alternate sessions; and three patients were studied once. Patients were randomly assigned to start the SBT with a T-piece (n=10 sessions) or with HFOT (n=9 sessions). With HFOT, VT and minute ventilation (VE) significantly increased during SBT (from [465±119] mL to [549±134] mL, P <0.001 and from [12.4±4.3] L/min to [13.1±4.2] L/min, P <0.05, respectively), but they did not change significantly during SBT with T-piece (from [495±132] mL to [461±123] mL and from [12.8±4.4] mL to [12.0±4.4] mL, respectively); f/VT decreased during HFOT (from [64±31] breaths/(min∙L) to [49±24] breaths/(min∙L), P <0.001), but it did not change significantly during SBT with T-piece (from [59±28] breaths/(min∙L) to [64±33] breaths/(min∙L)); partial pressure of arterial oxygen increased during HFOT (from [99±39] mmHg to [132±48] mmHg, P <0.001), but it decreased during SBT with T-piece (from [124±50] mmHg to [83±22] mmHg, P <0.01). In addition, with HFOT, diaphragmatic excursion increased (from [12.9±3.3] mm to [15.7±4.4] mm, P <0.001), but it did not change significantly during SBT with T-piece (from [13.4±3.3] mm to [13.6±3.3] mm). The diaphragmatic thickening fraction did not change during SBT either with T-piece or with HFOT. ConclusionIn patients with prolonged mechanical ventilation, HFOT through tracheostomy compared with T-piece improves ventilation, pattern of breathing, and oxygenation without increasing the inspiratory muscle effort. Trial RegistrationClinicaltrials.gov ldentifer: NCT04758910.

Diaphragm Assessment by Multimodal Ultrasound Imaging in Healthy Subjects.

In recent years, diaphragm ultrasound (DUS) has been used to identify diaphragm dysfunction in the intensive care unit (ICU). However, there are few studies on DUS parameters to evaluate function, normal ranges, and influencing factors in population. The aim of this study is to provide a methodological reference for clinical evaluation of diaphragm function by measuring different DUS parameters in a healthy population. A descriptive study was conducted 212 (105 males, 107 females) subjects with normal spirometry underwent ultrasound imaging in this study. The diaphragm contraction and motion related parameters and shear wave velocity (SWV) were measured in the supine position. The effects of gender, age, body mass index (BMI) and lifestyle on diaphragm ultrasound parameters were analyzed. The diaphragm thickness at end-expiration (DT-exp) was 0.14 ±0.05 cm, the diaphragm thickness at end- inspiration (DT-insp) was 0.29±0.10 cm, with thickening fraction (TF) was 1.11±0.54. The diaphragm excursion (DE) was 1.68±0.37cm and diaphragm velocity was 1.45±0.41 cm/s during calm breathing. During deep breathing, the DE was 5.06±1.40cm and diaphragm velocity was 3.20±1.18 cm/s. The Diaphragm shear modulus-longitudinal view were Mean16.72±4.07kPa, Max25.04±5.58kPa, Min11.06±3.88kPa, SD2.56±0.98. The results of diaphragmatic measurement showed that the DT of males was significantly greater than that of females (P< 0.05), but there was no significant difference in TF. The DT-insp (r=0.155, P= 0.024) and the DT-exp (r=0.252, P=0.000) were positively correlated with age, and the DE during calm breathing was negatively correlated with age (r=-0.218, P= 0.001) and BMI (r=-00.280, P= 0.000). The DE (R=0.371, P=0.000) and velocity (R=0.368, P=0.000) during deep breathing were correlated with lifestyle. Our study provides normal reference values of the diaphragm and evaluates the influence of gender, age, body mass index and lifestyle on diaphragmatic morphology.

Association between nutritional risk status and both diaphragmatic dysfunction and diaphragm atrophy in medical ıntensive care unit patients.

Aim: critical illness often leads to malnutrition and diaphragmatic dysfunction (DD), common in intensive care units (ICU). Ultrasonography (US) is a potent tool for detecting DD. This study examines the connection between malnutrition risk and DD in ICU patients using ultrasonographic diaphragm measurements in medical ICU patients. Methods: we assessed nutritional risk using risk screening tools and mid-upper arm circumference measurements (MUAC). Diaphragm atrophy (DA) and DD were evaluated by measuring diaphragmatic excursion (DE), thickness, and thickening fraction (TF) by US. We then compared these diaphragmatic measurements in patients based on their nutritional risk scores. Results: of the fifty patients studied, 54 % to 78 % were at risk of malnutrition, 28 % exhibited diaphragm atrophy (DA), and 24 % showed DD upon ICU admission. Malnutrition risk diagnosed by all nutritional risk screening tools was significantly more frequent in patients with DD, while diagnosed by MUAC was considerably higher in patients with DA. A total of 16 patients (32 %) died during their ICU stay, with DD, DA, and malnutrition risks (as identified by the mNUTRIC Score) being more prevalent among non-survivors (p < 0.05). Malnutrition risk (as determined by the mNUTRIC Score) was an independent risk factor for DD [OR (95 % CI): 6.6 (1.3-34), p = 0.03]. Conclusion: malnutrition risk may be significantly associated with DD and DA in medical ICU patients upon ICU admission.

Use of a combination of diaphragmatic ultrasound and muscle relaxation monitoring in predicting post-extubation adverse respiratory events among elderly patients in an anesthesia intensive care unit

ObjectiveThe purpose of this study was to examine the feasibility of using a combination of diaphragmatic ultrasound and muscle relaxation monitoring in predicting adverse respiratory events after extubation among elderly patients in an anesthetic intensive care unit (AICU).MethodsThe study participants were 120 elderly patients who were in the AICU after laparoscopic radical resection for colorectal cancer. Based on whether there were critical respiratory events (CREs) after extubation, they were divided into the adverse event group and the non-adverse event group. We used logistic regression to identify factors influencing the occurrence of CREs post-extubation in elderly patients. Using the receiver operating characteristic (ROC) curve, we analyzed the value of each indicator in predicting CREs post-extubation.ResultsWe included 109 patients in the final analysis. In the adverse event group (n = 19), the age, proportion of females, and proportion of preoperative respiratory diseases were higher than in the non-adverse event group (n = 90). The muscle relaxation value, quiet breathing diaphragmatic excursion during extubation (DE-QB), deep breathing diaphragmatic excursion during extubation (DE-DB), and deep breathing diaphragmatic thickening fraction during extubation (DTF-DB) of patients in the adverse event group were significantly lower than those in the non-adverse event group (P < 0.05). Using binary logistic regression analysis, we identified muscle relaxation value, DE-DB, and DTF-DB during extubation as significant predictors of CREs post-extubation in elderly patients (P < 0.05). The area under the curve (AUC) of the combination of the muscle relaxation value, DE-DB, and DTF-DB during extubation for predicting CREs after extubation in elderly patients was 0.949, which was higher than that of any single indicator.ConclusionThe combination of diaphragmatic ultrasound and muscle relaxation monitoring was more accurate in predicting CREs post-extubation among elderly patients in the AICU.

Evaluation of diaphragm functions with diaphragm ultrasound and pulmonary function tests in individuals with Friedreich's ataxia.

It is known that the correlation of pulmonary function tests (PFT) with muscle dysfunction is insufficient. Here, we aimed to evaluate the diaphragm functions in individuals with Friedreich's ataxia (FRDA) and to examine its relationship with respiratory parameters and disease severity. This prospective study, conducted between November and December 2022, at Erciyes University, included 14 individuals with genetically confirmed FRDA and an age- and gender-matched healthy control group of eight individuals. We examined pulmonary functions with spirometric methods and evaluated diaphragm excursion, and diaphragm thickness-expiratory (Tde) and - end of inspiration (Tdi) with ultrasonography during calm breathing. Thickening fraction (TF) calculated. Also, we examined PaCO2 at rest. The neurological status of individuals was assessed using the Scale for the Assessment and Rating of Ataxia (SARA). The mean values of FEV1(lt), FEV1(%), FVC (lt), and FVC (%) were higher in the control group (p; <0.001, 0.013, <0.001, and 0.009, respectively). Also, mean Tdi, Tde, excursion and TF were lower in the FRDA group compared to the control group (p = 0.005, 0.294,0.005, and 0.019, respectively). The mean excursion value was 1.13 ± 0.54cm in the FRDA group and 1.71 ± 0.49cm in the control group. There is a strong, negative, and statistically significant correlation between SARA total score with excursion and TF (r = -0.7432, p = 0.002; r = -0.697, p = 0.008). There is no statistically significant relationship between excursion and BMI, standing-to-supine decrease in FVC, FEV1, and PaCO2. Also, the relationship between maximal inspiratory pressure (PImax) and excursion was moderate. Diaphragm ultrasound may reveal respiratory dysfunction better than PFT. Diaphragm excursion and TF are associated with disease scores in individuals with FDRA. Further studies are needed regarding the detection of alveolar hypoventilation.

Predictive value of diaphragmatic thickening fraction combined with MRC score for the outcome of weaning from mechanical ventilation in ICU-acquired weakness patients

To explore the predictive value of diaphragmatic thickening fraction (DTF) combined with Medical Research Council-score (MRC score) on the outcome of weaning from mechanical ventilation in ICU-acquired weakness (ICU-AW) patients. A retrospective case-control study was conducted. The clinical data of mechanically ventilated patients with an MRC score of less than 48 admitted to the department of critical care medicine of the First Affiliated Hospital of Wannan Medical College from January 2022 to March 2023 were collected, including general information, ultrasound indicators, MRC scores, main clinical outcomes, and weaning outcomes. Patients were divided into successful weaning group and failed weaning group according to whether the patient could maintain effective autonomous breathing for at least 48 hours without using an invasive or non-invasive ventilator. The clinical data of the two groups were compared. Receiver operator characteristic curve (ROC curve) was plotted to analyze the predictive value of DTF and MRC score alone or in combination for successful weaning of patients. A total of 87 patients were enrolled, of which 58 were successful weaning and 29 were failed weaning. There were no statistically significant differences in general data such as gender, age, underlying disease, heart rate (HR), mean arterial pressure (MAP), pH value, blood lactic acid (Lac), oxygenation index (PaO2/FiO2), and severity scores between the two groups. Compared with the failed weaning group, the DTF and MRC scores of patients in the successful weaning group were significantly increased [DTF: (26.02±2.68)% vs. (22.79±5.40)%, MRC score: 38.90±2.78 vs. 33.24±3.78, both P < 0.05]. The duration of mechanical ventilation and the length of ICU stay of patients in the successful weaning group were significantly shorter than those in the failed weaning group [duration of mechanical ventilation (hours): 102.21±32.60 vs. 113.14±41.34, length of ICU stay (days): 6.48±2.18 vs. 10.11±4.01, both P < 0.05], and the re-intubation rate and ICU hospitalization cost were significantly lowered [re-intubation rate: 6.90% (4/58) vs. 27.59% (8/29), ICU hospitalization cost (10 000 RMB): 4.99±0.87 vs. 7.85±2.45, both P < 0.05]. ROC curve analysis showed that the area under the ROC curve (AUC) of DTF and MRC score for predicting successful weaning in ICU-AW mechanical ventilation patients was 0.839 [95% confidence interval (95%CI) was 0.746-0.931] and 0.799 (95%CI was 0.701-0.899), respectively. Using DTF ≥ 25.01% as the optimal cut-off value to predict successful weaning, the sensitivity was 82.76%, and the specificity was 72.41%. Predicting successful weaning based on an optimal cut-off value of MRC score of ≥ 35.50 had a sensitivity of 79.31% and a specificity of 70.69%. Based on the DTF ≥ 25.01% combined with MRC score ≥ 35.50, it was predicted that the weaning would be successful, with an AUC of 0.887 (95%CI was 0.812-0.962), sensitivity increased to 89.70%, and specificity increased to 79.30%. The DTF and MRC score have good guiding value for the selection of weaning timing and predicting the weaning outcomes in ICU-AW patients. Compared with independent DTF and MRC score, the combination of DTF and MRC score improves the predictive value of successful weaning in ICU-AW patients.