ObjectiveTo evaluate the predictive value of diaphragmatic rapid shallow breathing index (D-RSBI) for weaning outcome prediction.MethodsThis was a prospective observation study. Respiratory rate (RR) and tidal volume (Vt) were recorded at the end of spontaneous breathing trial, and both M-Mode and B-Mode ultrasonography were used to assess the right diaphragmatic displacement (DD). In parallel, outcome of the weaning attempt, length of mechanical ventilation, length of stay in intensive care unit (ICU) and mortality of ICU were recorded. According to the weaning outcome, the patients were grouped into the successful group and the failed group. The receiver operator characteristic (ROC) curve was used to assess the value of rapid shallow breathing index (RSBI, RR/Vt) and D-RSBI (RR/DD) in predicting weaning failure for ICU patients with mechanical ventilation.ResultsA total of 110 patients recruited in this study. Of them, 73 (66.4%) patients were successfully liberated from mechanical ventilation, and 37 patients failed (33.6%) weaning procedure. The RSBI and D-RSBI of the patients in the failed group were higher than those in the success weaning group (P<0.01). The area under the ROC curves of RSBI and D-RSBI for predicting weaning failure was 0.78 (95% confidence interval 0.69 - 0.87), 0.91 (95% confidence interval 0.85 - 0.97), respectively, a cutoff of RSBI>69 breaths/(L·min) yielded sensitivity of 55% and specificity of 89%, and a cutoff of D-RSBI>1.5 breaths/(min·mm) yielded sensitivity of 87% and specificity of 80%.ConclusionD-RSBI is more accurate than traditional RSBI in predicting the weaning outcome.
Objective To explore the application value of shear wave elastography (SWE) combined with diaphragmatic thickening fraction (DTF) and rapid shallow breathing index (RSBI) in predicting the results of weaning of patients with mechanical ventilation. Methods Fifty-two patients with severe illness who were hospitalized in this hospital from January 2022 to September 2022 were treated with mechanical ventilation. After meeting the conditions for weaning, they underwent spontaneous breathing test, and the diaphragm function of patients was evaluated by measuring DTF using ultrasound technology and shear modulus (SM) using SWE technology. According to the weaning results, they were divided into weaning success group and weaning failure group, The differences of mechanical ventilation time, acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) score, respiratory rate, RSBI, oxygenation index, DTF, SM and other parameters between the two groups were compared. Multivariate logistic regression was used to analyze the factors affecting the withdrawal results. The receiver operator characteristic (ROC) curve was used to evaluate the predictive value of potential influencing factors on the withdrawal results. Results There were 39 cases of successful withdrawal and 13 cases of failure. There were significant differences in mechanical ventilation time, respiratory rate, RSBI, DTF and SM between the successful weaning group and the failure group (P<0.05). Through multivariate logistic regression analysis, RSBI [area under the ROC curve (AUC)=0.771, 95% confidence interval (CI) 0.589 - 0.953], DTF (AUC=0.806, 95%CI 0.661 - 0.951), SM (AUC=0.838, 95%CI 0.695 - 0.981) were independent factors that affected the results of withdrawal. The single parameter AUC was smaller than the combined index with RSBI≤70.48 times·min–1L–1, DTF≥30.0%, SM≥10.0 kPa as the cutoff value (AUC=0.937, 95%CI 0.714 - 1.0, diagnostic sensitivity, specificity and accuracy were 94.9%, 84.6% and 92.3% respectively). Conclusions SWE technology provides a new quantitative index for evaluating diaphragm function by evaluating diaphragm stiffness. Diaphragm stiffness combined with DTF and RSBI can better predict the successful withdrawal in patients with mechanical ventilation.
ObjectiveTo clarify the risk factors of diaphragmatic dysfunction (DD) after cardiac surgery with extracorporeal circulation. MethodsA retrospective analysis was conducted on the data of patients who underwent cardiac surgery with extracorporeal circulation in the Department of Cardiovascular Surgery of Peking University People's Hospital from January 2023 to March 2024. Patients were divided into two groups according to the results of bedside diaphragm ultrasound: a DD group and a control group. The preoperative, intraoperative, and postoperative indicators of the patients were compared and analyzed, and independent risk factors for DD were screened using multivariate logistic regression analysis. ResultsA total of 281 patients were included, with 32 patients in the DD group, including 23 males and 9 females, with an average age of (64.0±13.5) years. There were 249 patients in the control group, including 189 males and 60 females, with an average age of (58.0±11.2) years. The body mass index of the DD group was lower than that of the control group [(18.4±1.5) kg/m2 vs. (21.9±1.8) kg/m2, P=0.004], and the prevalence of hypertension, chronic obstructive pulmonary disease, heart failure, and renal insufficiency was higher in the DD group (P<0.05). There was no statistical difference in intraoperative indicators (operation method, extracorporeal circulation time, aortic clamping time, and intraoperative nasopharyngeal temperature) between the two groups (P>0.05). In terms of postoperative aspects, the peak postoperative blood glucose in the DD group was significantly higher than that in the control group (P=0.001), and the proportion of patients requiring continuous renal replacement therapy was significantly higher than that in the control group (P=0.001). The postoperative reintubation rate, tracheotomy rate, mechanical ventilation time, and intensive care unit stay time in the DD group were higher or longer than those in the control group (P<0.05). Multivariate logistic regression analysis showed that low body mass index [OR=0.72, 95%CI (0.41, 0.88), P=0.011], preoperative dialysis [OR=2.51, 95%CI (1.89, 4.14), P=0.027], low left ventricular ejection fraction [OR=0.88, 95%CI (0.71, 0.93), P=0.046], and postoperative hyperglycemia [OR=3.27, 95%CI (2.58, 5.32), P=0.009] were independent risk factors for DD. ConclusionThe incidence of DD is relatively high after cardiac surgery, and low body mass index, preoperative renal insufficiency requiring dialysis, low left ventricular ejection fraction, and postoperative hyperglycemia are risk factors for DD.
膈神经是维持呼吸功能的主要神经, 由颈3 ～5 神经组成, 在维持正常通气功能中占有重要的地位。膈肌位于胸腔和腹腔之间, 为向上膨隆呈穹窿形的扁薄阔肌, 是主要的呼吸肌, 在呼吸运动中起着非常重要的作用。膈肌起搏即通过电刺激膈神经或膈肌使膈肌收缩, 维持患有膈肌功能障碍患者的自然负压呼吸。自发现电刺激能引起膈肌收缩至今已有200 多年历史, 该技术应用于临床也已有60 余年历史[1] 。
The diaphragm is the main respiratory muscle in the body. The onset detection of the surface diaphragmatic electromyography (sEMGdi) can be used in the respiratory rehabilitation training of the hemiparetic stroke patients, but the existence of electrocardiography (ECG) increases the difficulty of onset detection. Therefore, a method based on sample entropy (SampEn) and individualized threshold, referred to as SampEn method, was proposed to detect onset of muscle activity in this paper, which involved the extraction of SampEn features, the optimization of the SampEn parameters w and r0, the selection of individualized threshold and the establishment of the judgment conditions. In this paper, three methods were used to compare onset detection accuracy with the SampEn method, which contained root mean square (RMS) with wavelet transform (WT), Teager-Kaiser energy operator (TKE) with wavelet transform and TKE without wavelet transform, respectively. sEMGdi signals of 12 healthy subjects in 2 different breathing ways were collected for signal synthesis and methods detection. The cumulative sum of the absolute value of error τ was used as an judgement value to evaluate the accuracy of the four methods. The results show that SampEn method can achieve higher and more stable detection precision than the other three methods, which is an onset detection method that can adapt to individual differences and achieve high detection accuracy without ECG denoising, providing a basis for sEMGdi based respiratory rehabilitation training and real time interaction.
Objective Exploring the correlation between intravesical pressure (IP) and diaphragm excursion (DE) in patients with severe acute pancreatitis (SAP) and acute respiratory distress syndrome (ARDS), and evaluating its predictive value for weaning outcomes. Methods A retrospective analysis was conducted on the clinical data of 144 SAP patients with ARDS admitted between 2020 and 2023. By collecting the outcome of weaning, collect data on gender, age, acute physiology and chronic health score II (APACHE II), oxygenation index, and IP and DE before weaning and extubation for all patients. Based on weaning outcomes, divide patients into successful and failed groups, and compare the differences in various indicators between the two groups; Use binary logistic regression to analyze whether IP and DE are risk factors affecting weaning in SAP patients with ARDS, and use Pearson correlation analysis to examine the correlation between IP and DE; Use receiver operating characteristic curve (ROC curve) to analyze the predictive value of IP and DE on weaning outcomes in SAP patients with ARDS. ResultsA total of 144 SAP patients with ARDS were included, of which 108 were successfully weaned and 36 were unsuccessful. There were no statistically significant differences in gender, age, and APACHE II scores between the successful and failed groups (males: 62.96% (68/108) compared to 69.44% (25/36), age (years): 41.91 ± 8.14 compared to 42.42 ± 6.22, APACHE II score (points): 18.28 ± 2.22 compared to 18.97 ± 1.83, P>0.05). The IP of the successful group was significantly lower than that of the failed group, and the DE was significantly higher than that of the failed group [IP (mmHg): 18.45 ± 3.76 compared to 23.92 ± 5.65, DE (mm): 16.18 ± 4.23 compared to 12.28 ± 4.44, all P<0.05]. All patients showed a significant negative correlation between IP and DE (r=–0.457, P<0.001). ROC curve analysis showed that the area under the curve (AUC) of IP predicting the withdrawal outcome of SAP patients with ARDS was 0.805, with a 95% confidence interval (95%CI) of 0.724-0.885 and P<0.001. When the cutoff value was 19.5 mmHg, the sensitivity was 91.57% and the specificity was 47.54%; The AUC for predicting the withdrawal outcome of SAP patients with ARDS by DE was 0.738, with a 95%CI of 0.641-0.834 and P<0.001. When the cutoff value was 11.5 points, the sensitivity was 84.82% and the specificity was 59.38%. Conclusions There is a significant negative correlation between IP and DE in SAP combined with ARDS patients, and both have certain predictive value for weaning outcomes.
ObjectiveTwitch transdiaphragmatic pressure is used to evaluate the diaphragm function of mechanical ventilated chronic obstructive pulmonary disease patients before weaning in the intensive care unit, and compared with healthy normal values.MethodsPatients were recruited if they were with acute exacerbation of chronic obstructive pulmonary disease, admitted between May to November in 2013 and December 2014 to February 2016 to the intensive care unit in the First Affiliated Hospital of Guangzhou Medical University, intubated and mechanical ventilated more than 72 hours, and recovered to the clinical stability states after passing the readiness to wean, getting ready for spontaneous breathing test. The newly designed esophageal electrode catheter and bilateral anterolateral magnetic phrenic nerves stimulation were utilized to detect the twitch transdiaphragmatic pressure. At the same time, the function of diaphragm was detected in 10 healthy adults for comparison.ResultsTwenty-two patients were recruited in this study. Two cases had no twitch signals. In the rest 20 cases, the twitch transdiaphragmatic pressure was (7.6±2.5) cm H2O. In 10 healthy adults, twitch transdiaphragmatic pressure was (26.7±4.9) cm H2O. There was significant difference between the patients and the health control subjects (P<0.05).ConclusionTwitch transdiaphragmatic pressure is significantly decreased in weaning chronic obstructive pulmonary disease patients compared with healthy adults.
目的报告32例膈肌破裂与创伤性膈疝的诊治体会。方法对该院收治的32例创伤性膈肌破裂进行回顾性分析。结果该32例中，开放性损伤12例，闭合性损伤20例，26例并发创伤性膈疝。经X线检查，18例有阳性发现； 16例行CT检查，结果均为阳性； 术前确诊24例（75%），治愈28例，死亡4例（12.5%）。结论CT和X线检查是诊断膈肌破裂和创伤性膈疝的主要依据。早期诊断、及时手术治疗是提高治愈率、降低死亡率的关键。
Objective To investigate the changes of respiratory mechanics in response to elevated respiratory central drive and their impacts on the inspiratory signals detection.Methods 10 normal volunteers were recruited for the study from the colleagues of the State Key Laboratory of Respiratory Disease. Rebreathing method was used to increase the end expiratory PCO2 ( PCO2 -ET) to the subject’s maximal tolerance in order to stimulate the increase of respiratory central drive. The changes of respiratory mechanics in response to elevated respiratory central drive and their impacts on the initiation signals of inspiration were observed.Results After re-breathing, the average maximal tolerated PCO2 -ET was ( 81. 2 ±6. 6) mm Hg. As the PCO2 -ET rising, electromyogram of diaphragmatic muscle ( RMSdi ) ,transdiaphragmatic pressure ( Pdi ) and tidal volume ( VT ) increased progressively while the time of respiratory cycle ( Ttot ) shorten gradually. As the PCO2 -ETlevel increased frombaseline [ PCO2 -ET( level-0) ] to the maximal level [ PCO2 -ET( level-4) ] , RMSdi increased from( 17. 17 ±12. 41) μV to ( 147. 99 ±161. 64) μV,Pdi and VT increased from ( 7. 5 ±1. 7) cmH2O and ( 0. 68 ±0. 27) L to ( 26. 13 ±11. 51) cm H2O and ( 2. 21 ±0. 37) L respectively, while Ttot shorten from ( 2. 91 ±0. 85) s to ( 1. 92 ±0. 39) s. These four parameters of respiratory mechanics, RMSdi, Pdi, VT and Ttot, were highly correlated linearly with PCO2 -ET ( r value was 0. 956, 0. 973,0. 956 and 0. 89 respectively, all P lt;0. 001) . At the start of inspiration, the first detectable signal was electromyogramof diaphragmatic muscle ( RMSdi) , followed by mouth pressure ( Pm)and inspiratory flow ( Flow) on time sequence. As the rising of PCO2 -ET, the time lag of Pmand Flow from RMSdi after the initiation of inspiration increased gradually. However, the time lag between Flow and Pm remained constant. Conclusions At the start of inspiration, the signal of RMSdi appears first as compared with Pm and Flow. As the rising of PCO2 -ET, the time lag of Pmand Flow fromRMSdi after the initiation of inspiration increased gradually, suggesting RMSdi is more sensitive inspiratory signal, which might be used for triggering of ventilator in order to improve the synchronization, especially in the situation of elevated respiratory central drive.