Diaphragm Function Research Articles

PHRENIC NERVE RECONSTRUCTION WITH SHORT-TERM DIAPHRAGM PACING CORRECTS DIAPHRAGM PARALYSIS DUE TO INTRATHORACIC NERVE INJURY.

Symptomatic diaphragm paralysis and subsequent pulmonary debilitation has been shown to occur following phrenic nerve injury within the thoracic cavity. In this study, we investigate the effectiveness of intrathoracic reconstruction of the phrenic nerve combined with short-term diaphragm pacing in restoring diaphragm function. A retrospective review of 34 consecutive patients who underwent intrathoracic phrenic nerve reconstruction and diaphragm pacing for symptomatic diaphragm paralysis was performed. Inclusion criteria included confirmation of diaphragm paralysis on chest fluoroscopy, BMI <40, Age <75, and presence of functional motor units on EMG testing. Surgical treatment consisted of intrathoracic phrenic nerve reconstruction with simultaneous implantation of a diaphragm pacemaker. 34 patients met inclusion criteria, including: 23 males and 11 females with an average age of 46 and average BMI of 28.5 kg/m2. Thirty patients (88%) reported improvement in respiratory function. FVC and FEV1 values improved by 15% (p=0.02) and 14% (p=0.049), respectively. A 375% increase in diaphragm motor amplitude was observed, from 0.04mV to 0.19mV (p=0.02). Radiographic improvement in resting diaphragm position and contraction was demonstrated in 71% of patients. Complications included pacemaker site infection (5%), cardiac arrythmia (5%), and asymptomatic abdominal bulge (3%). Intrathoracic phrenic nerve reconstruction with short-term diaphragm pacing is a safe and effective surgical treatment that improves diaphragm function and alleviates symptoms of respiratory insufficiency in patients with diaphragmatic paralysis following intrathoracic phrenic nerve injury. This approach should be considered as part of the treatment algorithm for this patient population.

Advances in achieving lung and diaphragm-protective ventilation.

Mechanical ventilation may have adverse effects on diaphragm and lung function. Lung- and diaphragm-protective ventilation is an approach that challenges the clinician to facilitate physiological respiratory efforts, while maintaining minimal lung stress and strain. Here, we discuss the latest advances in monitoring and interventions to achieve lung- and diaphragm protective ventilation. Noninvasive ventilator maneuvers (P0.1, airway occlusion pressure, pressure-muscle index) can accurately detect low and excessive respiratory efforts and high lung stress. Additional monitoring techniques include esophageal manometry, ultrasound, electrical activity of the diaphragm, and electrical impedance tomography. Recent trials demonstrate that a systematic approach to titrating inspiratory support and sedation facilitates lung- and diaphragm protective ventilation. Titration of positive-end expiratory pressure and, if available, veno-venous extracorporeal membrane oxygenation sweep gas flow may further modulate neural respiratory drive and effort to facilitate lung- and diaphragm protective ventilation. Achieving lung- and diaphragm-protective ventilation may require more than a single intervention; it demands a comprehensive understanding of the (neuro)physiology of breathing and mechanical ventilation, along with the application of a series of interventions under close monitoring. We suggest a bedside-approach to achieve lung- and diaphragm protective ventilation targets.

Endobronchial valve treatment improves diaphragm function in severe emphysema patients

Rationale and aimDiaphragm dysfunction is common in severe emphysema patients, primarily due to hyperinflation, placing the diaphragm at a mechanical disadvantage. Endobronchial valve (EBV) treatment is a bronchoscopic procedure to reduce hyperinflation, and thus potentially restore diaphragm function in this patient population. Our aim was to investigate the effect of EBV treatment on diaphragm function.Patients and methodsA prospective cohort study was performed in which diaphragm function was measured at baseline and 6 weeks after EBV treatment by ultrasonic assessment to measure diaphragm motion and diaphragm thickening fraction (dTF), surface electromyography (sEMG) to quantify diaphragm activity, and maximal inspiratory pressure (MIP) to assess diaphragm strength.ResultsTwenty-five patients were included, with a mean age of 64±7 years. Residual volume (−0.85±0.49 Liter, p&lt;0.001) decreased significantly post EBV treatment, with a significant increase in MIP (+0.6 kPa, range −1.2–2.8, p=0.001). Diaphragm motion on the treated side during tidal breathing significantly decreased (−3.3 mm, range −24.7–14.6, p=0.023). There were no significant changes in dTF on the treated side. Diaphragm activity (sEMG) for tidal breathing (−1.7 µV, p=0.004, range −8.8–5.8), maximal inspiration (−4.1 µV, p=0.004, range −42.3–16.0), and sniff manoeuvre (−6.1 µV, p=0.027, range −42.2–24.2) all significantly decreased.ConclusionOur results show that diaphragm function significantly improves after EBV treatment in severe emphysema patients. This emphasizes the physiological interaction between hyperinflation and diaphragm function, suggesting that reducing hyperinflation can at least partially reverse diaphragm dysfunction.

Lung ultrasound score and diaphragm ultrasound in weaning from mechanical ventilation: are they different in patients with and without COVID-19?

Objective: To compare pre-extubation physiological characteristics and ultrasound variables between patients intubated for COVID-19 compared to a clinical population and those intubated for other reasons. Methods: This was a secondary analysis of a prospective cohort study of patients undergoing invasive mechanical ventilation (IMV) for more than 48 h. Patients were divided into two groups: those intubated for COVID-19-induced ARDS and those intubated for other clinical reasons. Ultrasound assessment of lung and diaphragm function was performed before extubation. The results were compared between the two groups of patients. Results: In comparison with the patients without COVID-19, those with the disease were younger (a median age of 58 [46-76] years vs. a median age of 75 [69-85] years; p = 0.01), had fewer comorbidities (a median Charlson Comorbidity Index of 2 [1-4] vs. a median Charlson Comorbidity Index of 5 [4-6]; p &lt; 0.01), and were less severely ill at admission (a median APACHE II score of 9 [8-14] vs. a median APACHE II score of 18 [13-22]; p &lt; 0.01). In addition, the median duration of IMV was longer in the COVID-19 patients (11 [9-23] days vs. 6 [3-8] days; p &lt; 0.01). Although extubation success rates were similar between the COVID-19 and non-COVID-19 groups (22 [71%] vs. 35 [77.8%]), median lung ultrasound score differed between the two groups (23 [18-25] vs. 15 [11-18]; p &lt; 0.01), as did median diaphragmatic excursion (2.1 [1.7-2.4] vs. 1.7 [1.2-2.0]; p &lt; 0.01). Conclusions: Although patients with COVID-19 requiring ventilatory support are younger and have fewer comorbidities than those intubated for other clinical reasons, they experience longer hospital stays. Although lung ultrasound score can differ between patients with and without COVID-19, these differences do not significantly translate into extubation success rates. Therefore, the utility of ultrasound scores in weaning COVID-19 patients from IMV needs further study.

Poor correlation between diaphragm ultrasound and invasive gold standard technique derived respiratory muscle strength assessment in patients after hospitalization for COVID-19.

Individuals who survive acute coronavirus disease 2019 (COVID-19) might experience diaphragm muscle weakness. Diaphragm ultrasound may be an easy-to-obtain bedside tool for determining diaphragm function. However, twitch transdiaphragmatic pressure (twPdi) following magnetic stimulation (MS) of the phrenic nerves is the gold standard for non-volitional assessment of diaphragm strength. This study investigated whether diaphragm thickening ratio (DTR) measured on diaphragm ultrasound reflects diaphragm strength as measured by twPdi following MS of the phrenic nerves or other (volitional) invasively obtained pressure values and could therefore be used to accurately diagnose diaphragm weakness. One year after discharge, 50 individuals (14 female, age 58±12 years) who had been hospitalised and treated for moderate-severe COVID-19 underwent standard spirometry and diaphragm ultrasound. TwPdi following cervical MS of the phrenic nerve and volitional inspiratory manoeuvres (Sniff and Mueller manoeuvre) were measured using oesophageal and gastric balloon catheters after transnasal placement. At follow-up, no clinically meaningful restrictive lung function impairment was evident on spirometry. On diaphragm ultrasound, diaphragm dysfunction, i. e. an impaired diaphragm thickening ratio was detected in 24% (12/50) of participants. An objective diagnosis of diaphragm dysfunction, defined as twPdi <16 cmH2O, was made in 60% (30/50) of participants. The measurement results of the two methods did not agree, given that there were many false negative, but also false positive results, so diaphragm ultrasound diagnosed in parts other patients with diaphragm dysfunction than TwPdi. Diaphragm ultrasound had a sensitivity of 26.67% and a specificity of 80.0% in the detection of diaphragm dysfunction (Positive predictive value 66.67%, negative predictive value 42.10%). Diagnosis of diaphragm weakness in individuals who have recovered from COVID-19 cannot be made accurately on diaphragm ultrasound (via DTR), but requires twPdi as the gold standard for assessment of diaphragm strength.

Validation of a novel point-of-care ultrasound method to assess diaphragmatic excursion

IntroductionPoint-of-care ultrasound can assess diaphragmatic function and rule in or rule out paresis of the diaphragm. While this is a useful bedside tool, established methods have significant limitations. This study...

Diaphragm Function in Elite Weightlifters With and Without Chronic Low Back Pain and its Impacts on Sports Performance.

Zhou, EFM, Wong, AYL, Peng, J, Lin, G, Wen, T, Fang, J, Zhou, C, and Fu, SN. Diaphragm function in elite weightlifters with and without chronic low back pain and its impacts on sports performance. J Strength Cond Res XX(X): 000-000, 2024-The aim of this study was to compare diaphragm function between elite weightlifters with and without chronic low back pain (LBP) and to explore the associations between diaphragm function and sports performance. Forty-nine elite weightlifters aged 16-26 years were recruited, including 29 women (16-25 years, mean ± SD = 19.93 ± 2.70 years) and 20 men (16-26 years, mean ± SD = 20.95 ± 2.68 years). Of these, 23 subjects had chronic LBP. Diaphragm thickness and excursion were assessed using ultrasonography, and maximal inspiratory pressure (MIP), measured with POWERbreathe KH2, served as indicators of diaphragm contractility and strength, respectively. Sports performance was gauged through maximal snatch and clean and jerk lifts. Group differences and performance correlations were analyzed with consideration for confounders. The significance was set at p ≤ 0.05. Weightlifters with chronic LBP demonstrated significantly lower diaphragmatic contractility: diaphragm thickening fraction (by 21%; mean difference [MD] = 0.09, p = 0.04, Cohen's d = 0.69) and diaphragm excursion (by 18%; MD = 0.99, p < 0.01, Cohen's d = 0.89) compared with non-LBP controls. In addition, MIP was positively related to snatch (r = 0.34, p = 0.02) and clean and jerk (r = 0.43, p < 0.01) lifts. This study revealed that elite weightlifters with chronic LBP exhibit reduced diaphragm contractility, and inspiratory muscle force output (primary diaphragm) was associated with lifting performance. Incorporating diaphragm strengthening into training and rehabilitation might enhance performance and aid in LBP management, offering a dual benefit for athletes.

Impact of COVID-19 on Diaphragmatic Function: Understanding Multiorgan Involvement and Long-Term Consequences.

The COVID-19 pandemic has brought significant attention to the respiratory system, with much focus on lung-related disorders. However, the diaphragm, a crucial component of respiratory physiology, has not been adequately studied, especially in the context of long COVID. This review explores the multipotential role of the diaphragm in both respiratory health and disease, emphasizing its involvement in long-term complications following SARS-CoV-2 infection. The diaphragm's fundamental role in respiratory physiology and its impact on balance and posture control, breathing patterns, and autonomic nervous system regulation are discussed. This review examines complications arising from COVID-19, highlighting the diaphragm's involvement in neurological, musculoskeletal, and inflammatory responses. Particular attention is given to the neuroinvasive impact of SARS-CoV-2, the inflammatory response, and the direct viral effects on the diaphragm. The diaphragm's role in long COVID is explored, with a focus on specific symptoms such as voice disorders, pelvic floor dysfunction, and sleep disturbances. Diagnostic challenges, current methods for assessing diaphragmatic dysfunction, and the complexities of differentiating it from other conditions are also explored. This article is the first to comprehensively address diaphragmatic dysfunction resulting from COVID-19 and long COVID across various physiological and pathological aspects, offering a new perspective on its diagnosis and treatment within a multisystem context.

Visual Patterns of Diaphragmatic Motion in Acute Respiratory Failure: A Prospective Pilot Study.

Right diaphragmatic excursion is a reliable and reproducible technique used in intensive care to assess diaphragmatic function. The aim of this study was to investigate the relationship between the appearance of diaphragmatic motion and the etiological diagnosis of patients admitted to the emergency department with acute respiratory failure (ARF). A prospective, observational, and multicenter pilot study was conducted. All adult patients admitted in the emergency department with ARF were included. The different visual patterns of diaphragmatic motion were analyzed according to the three main etiologies of ARF encountered in emergency departments. A total of 39 adult patients were included. We observed a different visual pattern in patients with pneumonia. A sum of plateau times of less than 0.2 s predicted that the main diagnosis was pneumonia, with sensitivity = 89% 95%CI [52%; 100%], specificity = 87% 95%CI [69%; 96%]. Our study seems to show that the shape of diaphragmatic motion in patients with ARF secondary to pneumonia is different from that in patients with exacerbation of chronic obstructive pulmonary disease or acute heart failure. ClinicalTrials.gov: NCT04591509.

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.

Ultrasound guided transcutaneous phrenic nerve stimulation in critically ill patients: a new method to evaluate diaphragmatic function.

Diaphragm dysfunction is common in intensive care unit and associated with weaning failure and mortality. Diagnosis gold standard is the transdiaphragmatic or tracheal pressure induced by magnetic phrenic nerve stimulation. However, the equipment is not commonly available and requires specific technical skills. We aimed to evaluate ultrasound guided transcutaneous phrenic nerve stimulation for daily bedside assessment of diaphragm function by targeted electrical phrenic nerve stimulation. In this randomized cross-over study we compared a new method of ultrasound guided transcutaneous electrical phrenic nerve stimulation (SONOTEPS method) using a peripheral nerve stimulator, with the magnetic phrenic nerve stimulation. Intensive care unit adult patients under mechanical ventilation with a Richmond-Agitation-Sedation-Scale score of -4 or -5 were included. Each patient received the two methods of stimulation, in a randomized order. The primary outcome was the tracheal pressure (Ptrach) induced by stimulation. We analyzed 232 measures of Ptrach from 116 patients of whom 77 presented a diaphragm dysfunction (Ptrach < 11 cmH2O) and 50 a severe diaphragm dysfunction (Ptrach < 8 cmH2O). The Passing-Bablok regression showed no significant differences (intercept A of -0.03 [CI95:-0.83-0.52] and slope B of 0.98 [CI95:0.90-1.05]) between SONOTEPS method and magnetic stimulation which were positively correlated (R²=0.639). The mean bias was -1.08 (CI95 5.02, -7.18) cmH2O. The receiver operating curves showed an excellent performance for the diagnosis of diaphragm dysfunction and severe diaphragm dysfunction with respectively an area under curve of 0.90 (CI95 0.83-0.97) and 0.88 (CI95 0.82-0.95). This performance was not significantly affected by the body mass index or the presence of a neck catheter. The SONOTEPS method is a simple and accurate tool for bedside assessment of diaphragm function with ultrasound guided transcutaneous phrenic nerve stimulation in sedated patients with no or minimal spontaneous respiratory activity.

Early diaphragm dysfunction assessed by ultrasonography after cardiac surgery: a retrospective cohort study.

Approximately 10%-70% of patients may develop diaphragmatic dysfunction after cardiac surgery, which may lead to delayed weaning from mechanical ventilation, increased ICU stays, postoperative hospitalization stays, and respiratory complications. However, its impact on prognosis and risk factors remain controversy. Therefore, we conducted a retrospective cohort study in which we evaluated diaphragmatic dysfunction in patients who underwent cardiac surgery via bedside diaphragm ultrasound to investigate its prognosis and possible risk factors. Data from the electronic medical records system included case records and ultrasound images of the diaphragm for 177 consecutive patients admitted to the ICU following cardiac thoracotomy surgeries performed between June and September 2020. Diaphragmatic dysfunction was defined as a diaphragmatic excursion of less than 9 mm in women and less than 10 mm in men at rest, with an average thickening fraction of less than 20%. SPSS 25.0 software was used to analyse the relationships between patients' general information, intraoperative and postoperative factors and diaphragmatic dysfunction, as well as the impact on patients' hospitalization days, mechanical ventilation time and respiratory system complications. The incidence of early postoperative diaphragmatic dysfunction after cardiac surgery was 40.7%. Patients with diaphragmatic insufficiency were more likely to sequentially use noninvasive ventilation within 24 h after weaning off mechanical ventilation (3.8% vs. 12.5%, P = 0.029) and to require more oxygen support (23.8% vs. 40.3%, P = 0.019). Although there was no significant difference, the diaphragmatic dysfunction group tended to have longer ICU stays and postoperative hospital stays than did the normal diaphragmatic function group (P = 0.119, P = 0.073). Univariate and multivariate logistic regression analyses both revealed that chest tube drainage placed during surgery accompanied by bloody drainage fluid was an independent risk factor for diaphragmatic dysfunction (univariate analysis: 95% CI: 1.126-4.137, P = 0.021; multivariate analysis: 95% CI: 1.036-3.897, P = 0.039). Eearly diaphragmatic dysfunction after cardiac surgery increased the proportion of patients who underwent sequential noninvasive ventilation after weaning from mechanical ventilation and who required more oxygen. Chest tube drainage placed during surgery accompanied by bloody drainage fluid was an independent risk factor for diaphragmatic dysfunction, providing evidence-based guidance for respiratory rehabilitation after cardiac surgery.

Perioperative assessment of diaphragmatic dysfunction in cardiac surgery patients and its effect on outcome; a prospective observational study

Objectives: While the assessment of the diaphragm in different clinical scenarios is quite frequent, there remains a scarcity of studies focused on assessing diaphragm dysfunction using ultrasound in cardiac surgery patients. We investigated the impact of cardiopulmonary bypass (CPB) surgery on diaphragm function and evaluated its effects on mechanical ventilation. Methodology: A prospective cohort study, on 100 consecutive adult cardiac surgery patients, was conducted at National Heart Institute. Diaphragmatic displacement (DD) or excursion and diaphragmatic thickening fraction (DTF) were measured using motion-mode ultrasound during quite normal breathing pre-operatively (the day before surgery) and post-operatively on mechanical ventilation, while the patient was fully conscious and spontaneously breathing on continuous positive airway pressure (CPAP) mode + pressure support 10 cmH2O. Then, the results were correlated to CBP time and important patient outcomes. Results: Post-operative DD was significantly less as compared to the pre-operative reading; (1.39 ± 0.42 cm vs. 2.3 ± 0.52 cm; P &lt; 0.001), as was DTF (23% ± 10% vs. 40% ± 13%; P &lt; 0.001). The incidence of diaphragmatic dysfunction post-cardiac surgery was 17% by the definition of DD &lt; 1 cm, and 49% by the definition of DTF ≤ 20%. DD was positively correlated with CBP time, as well as total ventilation time and ICU stay, indicating a negative impact on overall patient outcomes. Conclusion: The results suggest that diaphragmatic dysfunction is positively correlated with CPB time, total ventilation time and ICU stay, underscoring the importance of monitoring diaphragmatic function in post-operative patients, who are difficult to wean from mechanical ventilation with apparently normal chest X-ray, particularly those with prolonged CPB time. Keywords: cardiac surgery; cardiopulmonary bypass; diaphragm dysfunction; diaphragmatic displacement; diaphragm ultrasound; mechanical ventilation. Citation: Omara ISM, Nagi HK, Mohamed KAA, Abd El Haq HH, Awdallah FF. Perioperative assessment of diaphragmatic dysfunction in cardiac surgery patients and its effect on outcome; a prospective observational study. Anaesth. pain intensive care 2024;28(5):816−823; DOI: 10.35975/apic.v28i5.2555 Received: June 28, 2024; Reviewed: September 04, 2024; Accepted: September 06, 2024

Double-Chamber Underwater Thruster Diaphragm with Flexible Displacement Detection Function.

The purpose of this paper is to develop a self-detecting diaphragm integrated with a flexible sensor, which is utilized in an underwater thruster. Resistive strain sensors are easy to manufacture and integrate due to their advantages in reliable stretchability and ductility. Inspired by the structure of neurons, we fabricated resistive flexible sensors using silica gel as the matrix with carbon black and carbon nanotubes as additives. All fabricated sensors demonstrated positive resistance characteristics under 60% strain conditions, with the sensor containing a mass ratio of 9 wt % carbon black and carbon nanotubes exhibiting the best resistance-strain linearity. To verify the anti-interference capability of sensors with silica gel substrates of varying hardness values under changing environmental pressure, we tested the pressure sensitivity of the sensors by altering the hardness of the silica gel. The results indicate that silica gel with the highest hardness value provides the best resistance to environmental pressure interference. To detect the motion and deformation of the internal functional components of the thruster, we combined strain detection with the movement operation function of a silica gel diaphragm, resulting in a new integrated diaphragm with sensor detection capabilities. The integrated diaphragm was evaluated by using a tensile testing machine and an LCR tester. The results demonstrate that the mechanical properties of the diaphragm are stable, exhibiting reliable resistance characteristics and a sensitive response during underwater operation. This research can also be applied to the detection of motion amplitudes of other types of soft robots.

Efficacy of ultrasonographic diaphragmatic parameters in distinguishing diaphragmatic dysfunction in cats.

Diaphragmatic dysfunction (DD) is often underdiagnosed in veterinary medicine. Various ultrasonographic diaphragmatic parameters, including diaphragmatic excursion (DE), diaphragmatic thickness (Tdi) and diaphragmatic thickening fraction (DTF), can be used to identify DD. We aimed to establish normal reference intervals in healthy cats, examine the effects of intrinsic factors on diaphragmatic parameters and evaluate the efficacy of these parameters in identifying DD in healthy and diseased cats. This prospective observational study was conducted on 22 healthy cats and 12 diseased cats using ultrasonographic techniques to evaluate DE, Tdi and DTF. The correlation between diaphragmatic parameters and intrinsic factors, including sex, age, body weight and body condition score, was analysed using Pearson correlation analysis. Cut-off values for healthy and diseased cats were established using receiver operating characteristic curve analysis. The mean DEs of the left and right hemidiaphragms were 0.66 ± 0.16 and 0.64 ± 0.18 cm, respectively. The mean Tdis in the end-inspiration phase were 0.13 ± 0.03 and 0.12 ± 0.03 cm for the left and right hemidiaphragms, respectively, whereas in the end-expiration phase the mean Tdi was 0.07 ± 0.03 cm for both hemidiaphragms. The DTF ranges for the left and right hemidiaphragms were 23.90-122.1% and 38.80-107%, respectively. Intrinsic factors had no significant impact on DE, Tdi and DTF. The DE measurements for the left hemidiaphragm were more accurate for evaluating diaphragmatic function. To distinguish between healthy and diseased cats, the cut-off value, sensitivity and specificity were 0.458 cm (area under the curve [AUC] 0.846), 75.00% and 86.36%, respectively, for the left hemidiaphragm and 0.423 cm (AUC 0.704), 41.67% and 100%, respectively, for the right hemidiaphragm. Normal reference values for DE, Tdi and DTF were established for healthy cats. DE, particularly in the left hemidiaphragm, obtained using routine ultrasonography, improves the efficacy of identifying DD and assists clinicians in the diagnosis and treatment of cats with cardiorespiratory disease.

Lung Ultrasound in Neonates: A Narrative Review Along With Diagnostic Insights and Early Postnatal Applications.

Ultrasound (US) has become a useful, bedside, noninvasive imaging techniquein diagnosing pulmonary diseases, particularly in Neonatology, due to its non-invasive nature, lack of ionizing radiation, and high-quality imaging. This study explores current methodologies, applications, and benefits of thoracic US in neonatal care, highlighting its application in assessing pleural morphology, pulmonary consolidations, and diaphragmatic function. Key ultrasound findings, such as A-lines, B-lines, and the pleural sliding sign, are instrumental in diagnosing various lung conditions, including pneumothorax and respiratory distress syndrome. The present review emphasizes the growing importance of lung ultrasound (LUS) in predicting neonatal intensive care needs, reducing reliance on X-rays, and improving the early diagnosis of conditions like transient tachypnea of the newborn. The use of ultrasound scoring systems enhances diagnostic accuracy, making thoracic ultrasound a valuable addition to neonatal care protocols for real-time, radiation-free assessment from birth.

Association of diaphragmatic dysfunction with duration of mechanical ventilation in patients in the pediatric intensive care unit: a prospective cohort study

BackgroundMechanical ventilation (MV) can cause diaphragmatic injury and ventilator induced diaphragmatic dysfunction (VIDD). Diaphragm ultrasonography (DU) is increasingly used to assess diaphragmatic anatomy, function and pathology of patients receiving MV in the pediatric intensive care unit (PICU). We report the poor contractile ability of diaphragm during ventilation of critically ill patients in our PICU and the association to prolonged length of MV and PICU stay.MethodsPatients who received MV within 24 h of admission to the PICU, expected to undergo continuous MV for more than 48 h and succeeded to extubate were included in the study. DU monitoring was performed daily after the initiation of MV until extubation. Diaphragm thickening fraction (DTF) measured by DU was used as an indicator of diaphragmatic contractile activity. Patients with bilateral DTF = 0% during DU assessment were allocated into the severe VIDD group (n = 26) and the rest were into non-severe VIDD group (n = 29). The association of severe VIDD with individual length of MV, hospitalization and PICU stay were analyzed.ResultsWith daily DU assessment, severe VIDD occurred on 2.9 ± 1.2 days after the initiation of MV, and lasted for 1.9 ± 1.7 days. Values of DTF of all patients recovered to > 10% before extubation. The severe VIDD group had a significantly longer duration (days) of MV [12.0 (8.0-19.3) vs. 5.0 (3.5–7.5), p < 0.001] and PICU stay (days) [30.5 (14.9–44.5) vs. 13.0 (7.0-24.5), p < 0.001]. The occurrence of severe VIDD, first day of severe VIDD and length of severe VIDD were significantly positively associated with the duration of MV and PICU stay. The occurrence of severe VIDD on the second and third days after initiation of MV significantly associated to longer PICU stay (days) [43.0 (9.0–70.0) vs. 13.0 (3.0–40.0), p = 0.009; 36.0 (17.0-208.0) vs. 13.0 (3.0–40.0), p = 0.005, respectively], and the length of MV (days) was significantly longer in those with severe VIDD on the third day after initiation of MV [16.5 (7.0–29.0) vs. 5.0 (2.0–22.0), p = 0.003].ConclusionsDaily monitoring of diaphragmatic function with bedside ultrasonography after initiation of MV is necessary in critically ill patients in PICU and the influences and risk factors of severe VIDD need to be further studied. (355 words)

Effect of low-volume ropivacaine in ultrasound-guided superior trunk block on diaphragmatic movement in patients undergoing shoulder arthroscopy: a randomized controlled trial

ObjectivesThe incidence of hemidiaphragmatic paresis (HDP) in superior trunk block (STB) usually depends on the dose of local anesthetic. This study aimed to further evaluate the impact of a lower volume (10 mL) of the same low concentration (0.25%) ropivacaine compared to a conventional volume (15 mL), on diaphragmatic function and analgesic efficacy under a multimodal analgesia regimen for shoulder arthroscopy.MethodsPatients scheduled to undergo shoulder arthroscopy were randomized allocated to receive either 10 mL or 15 mL of 0.25% ropivacaine in the STB under ultrasound guidance prior to general anesthesia. The primary outcome was the percentage reduction in diaphragm excursion (ΔDE) between baseline and 30 min after block. Secondary outcomes included DE and diaphragm thickening fraction (DTF) before and after block, incidence of HDP, onset of sensory/motor block, duration of analgesia/motor block, dermatomal coverage area of the block, postoperative pain severity, pre- and post-block respiratory function and intraoperative hemodynamic parameters, the use of other anesthetic and analgesic drugs, post-block complications, and adverse events post-surgery.ResultsCompared with 15 mL volume, 10 mL ropivacaine significantly reduced the incidence of post-block HDP (as measured by ΔDE: 39.47% vs. 64.10%; and by post-block DTF: 13.16% vs. 33.33%). There was no significant difference in onset of sensory block, duration of analgesia/motor block, dermatomal coverage area of the block, postoperative pain severity between the two groups, except that the onset of motor block was significantly slower in the 10 mL group than in the 15 mL group. Pre- and post-block respiratory function and intraoperative hemodynamic parameters, the use of other anesthetic and analgesic drugs, post-block complications, or postoperative adverse events were not significantly different between the two groups.ConclusionIn shoulder arthroscopy, STB with 10 mL of ropivacaine can reduce the incidence of HDP with no significant difference in analgesic effects under a multimodal analgesia regimen compared with 15 mL.Trial registration: We registered the study at chictr.org (ChiCTR2200057543 , 14/03/2022.https://www.chictr.ogr.cn

Hemi-diaphragm detection of chest X-ray images based on convolutional neural network and graphics.

Chest X-rays (CXR) are widely used to facilitate the diagnosis and treatment of critically ill and emergency patients in clinical practice. Accurate hemi-diaphragm detection based on postero-anterior (P-A) CXR images is crucial for the diaphragm function assessment of critically ill and emergency patients to provide precision healthcare for these vulnerable populations. Therefore, an effective and accurate hemi-diaphragm detection method for P-A CXR images is urgently developed to assess these vulnerable populations' diaphragm function. Based on the above, this paper proposes an effective hemi-diaphragm detection method for P-A CXR images based on the convolutional neural network (CNN) and graphics. First, we develop a robust and standard CNN model of pathological lungs trained by human P-A CXR images of normal and abnormal cases with multiple lung diseases to extract lung fields from P-A CXR images. Second, we propose a novel localization method of the cardiophrenic angle based on the two-dimensional projection morphology of the left and right lungs by graphics for detecting the hemi-diaphragm. The mean errors of the four key hemi-diaphragm points in the lung field mask images abstracted from static P-A CXR images based on five different segmentation models are 9.05, 7.19, 7.92, 7.27, and 6.73 pixels, respectively. Besides, the results also show that the mean errors of these four key hemi-diaphragm points in the lung field mask images abstracted from dynamic P-A CXR images based on these segmentation models are 5.50, 7.07, 4.43, 4.74, and 6.24 pixels,respectively. Our proposed hemi-diaphragm detection method can effectively perform hemi-diaphragm detection and may become an effective tool to assess these vulnerable populations' diaphragm function for precision healthcare.

Time course of electrical activity of the diaphragm (EAdi) in the peri extubation period and its role as predictor of extubation failure in difficult to wean patients

IntroductionWeaning patients from mechanical ventilation is crucial in the management of acute respiratory failure (ARF). Spontaneous breathing trials (SBT) are used to assess readiness for extubation, but extubation failure remains a challenge. Diaphragmatic function, measured by electrical activity of the diaphragm (EAdi), may provide insights into weaning outcomes.Materials and methodsThis prospective, observational study included difficult-to-wean patients undergoing invasive mechanical ventilation. EAdi was recorded before, during, and after extubation. Patients were categorized into extubation success and failure groups based on reintubation within 48 h. Statistical analysis assessed EAdi patterns and predictive value.ResultsThirty-one patients were analyzed, with six experiencing extubation failure. Overall, EAdi increased significantly between the phases before the SBT, the SBT and post-extubation period, up to 24 h (p < 0.001). EAdi values were higher in the extubation failure group during SBT (p = 0.01). An EAdi > 30 μV during SBT predicted extubation failure with 92% sensitivity and 67% specificity. Multivariable analysis confirmed EAdi as an independent predictor of extubation failure.ConclusionsIn difficult-to-wean patients, EAdi increases significantly between the phases before the SBT, the SBT and post-extubation period and is significantly higher in patients experiencing extubation failure. An EAdi > 30 μV during SBT may enhance extubation failure prediction compared to conventional parameters. Advanced monitoring of diaphragmatic function could improve weaning outcomes in critical care settings.