Possibilities of ultrasound research of the diaphragm

Ultrasonography Comparison of Diaphragm Morphological Structure and Function in Young and Middle-Aged Subjects with and without Non-Specific Chronic Low Back Pain: A Case-Control Study

Background

It is reported that impaired postural control in patients with non-specific chronic low back pain (NCLBP) was associated with "core" trunk muscle incoordination. However, as the diaphragm is an important component of the "core" deep trunk muscle group, we still know little about the potential relationship between diaphragm dysfunction and NCLBP.

Objectives

This case-control study is intended to investigate the changes of diaphragm morphological structure and function in young and middle-aged subjects with and without NCLBP by ultrasound evaluation and its possible validity in predicating the occurrence of NCLBP.

Methods

31 subjects with NCLBP (NCLBP group) and 32 matched healthy controls (HC group) were enrolled in this study. The diaphragm thickness at the end of inspiration (T ^ins) or expiration (T ^exp) during deep breathing was measured through B-mode ultrasound, and the diaphragm excursion (T ^exc) was estimated at deep breathing through M-mode ultrasound. The diaphragm thickness change rate (T ^rate) was calculated by the formula: T ^rate=(T ^ins - T ^exp)/T ^exp × 100%.

Results

Compared with the HC group, the NCLBP group had a significant smaller degree of T^ins (t = -3.90, P < 0.001), T ^exp (Z = -2.79, P=0.005), and T ^rate (t = -2.03, P=0.047). However, there was no statistical difference in T ^exc between the two groups (t = -1.42, P=0.161). The binary logistic regression analysis indicated that T ^rate (OR = 16.038, P=0.014) and T ^exp (OR = 7.714, P=0.004) were potential risk factors for the occurrence of NCLBP.

Conclusions

The diaphragm morphological structure and function were changed in young and middle-aged subjects with NCLBP, while the diaphragm thickness change rate (T ^rate) and diaphragm thickness at the end of expiration (T ^exp) may be conductive to the occurrence of NCLBP. Furthermore, these findings may suggest that abnormal diaphragm reeducation is necessary for the rehabilitation of patients with NCLBP.

Diyafram ultrasonografisinin weaning başarısını tahmin etmedeki gücü

Amaç: Bu çalışmada amaç; diyafram kalınlığının weaning üzerine etkilerini ultrasonografi (USG) ile değerlendirmektir. Gereç ve Yöntem: Prospektif olarak yapılan bu çalışmada; hastaların demografik özellikleri, yoğun bakıma yatış ve mekanik ventilasyon endikasyonları, ek hastalıkları, diyafram kalınlığı, Sıralı Organ Yetmezliği Değerlendirmesi (SOFA) skoru ve Basitleştirilmiş Akut Fizyoloji Skoru (SAPS) II, mortalite oranı, periferik oksijen satürasyonu (SpO2), IMV süresi, dakika hacmi, solunum sayısı (RR), ekspiratuar hacimleri, RSBI değerleri kaydedildi.Hastalar invaziv mekanik ventilatör (IMV) basınç desteği (PS) modunda 30 dakika boyunca spontan olarak ventile edildi . Diyafram kalınlığı (DT), B moduna ayarlanmış 7-10 MHz lineer ultrason probu kullanılarak ölçüldü. Sağ hemidiyafram, 8. ve 10. interkostal boşluklar arasındaki midaksiller çizgide diyafram ve göğüs kafesinin birleştiği bölgede görüntülendi. Ölçümler sonrasında hastalar stabil hale geldikten sonra 1 saat boyunca T-tüpe alındı. T-tüpte spontan solunum denemeleri (SBT)'ni başarıyla tamamlayan hastalar ekstübe edildi. Hastalar başarılı ve başarısız weaning olmak üzere 2 gruba ayrıldı. Bulgular: Toplam 72 hasta çalışmaya dahil edilme kriterlerini sağlayarak değerlendirilmeye alındı. Hastaların 4 tanesi 24 saatten daha kısa süre IMV desteği aldığı için çalışma dışı bırakıldı. Diyafram kalınlık indeksi (DTI) ve diyafram kalınlaşma fraksiyonu (DTF) oranlarında gruplar arasında bir farklılık gözlenmedi. İnspirasyon sonunu diyafram kalınlığı (DTV) ve ekspirasyon sonunu diyafram kalınlığı (DFRV) olarak tanımlanan diyaframın kalınlık ölçümleri başarılı weaning grubunda daha yüksekti. Weaning başarısını tahmin etmek için DTV'nin en iyi eşik değeri 0.72, DFRV değeri 0.669 olarak bulundu. Sonuç: Weaning başarısı diyafram fonksiyonları, diyafram kalınlık parametreleri ve akciğer kapasiteleri ile yakından ilişkilidir. USG, diyaframı değerlendirmek için kullanılabilecek pratik, hasta başı uygulanabilen, noninvaziv bir yöntemdir. DTV ve DFRV weaning sürecinde başarıyı tahmin edebilecek parametreler arasındadır. DTF ve DTI weaning başarısını öngörmede yetersiz bulundu.

Early rehabilitation relieves diaphragm dysfunction induced by prolonged mechanical ventilation: a randomised control study

BACKGROUND

Prolonged mechanical ventilation (MV) induces diaphragm dysfunction in patients in the intensive care units (ICUs). Our study aimed to explore the therapeutic efficacy of early rehabilitation therapy in patients with prolonged MV in the ICU.

METHODS

Eighty eligible patients who underwent MV for > 72 h in the ICU from June 2019 to March 2020 were enrolled in this prospective randomised controlled trial. The patients were randomly divided into a rehabilitation group (n = 39) and a control group (n = 41). Rehabilitation therapy included six levels of rehabilitation exercises. Diaphragm function was determined using ultrasound (US).

RESULTS

Diaphragmatic excursion (DE) and diaphragm thickening fraction (DTF) were significantly decreased in all patients in both groups after prolonged MV (p < 0.001). The rehabilitation group had significantly higher DTF (p = 0.008) and a smaller decrease in DTF (p = 0.026) than the control group after 3 days of rehabilitation training. The ventilator duration and intubation duration were significantly shorter in the rehabilitation group than in the control group (p = 0.045 and p = 0.037, respectively). There were no significant differences in the duration of ICU stay, proportion of patients undergoing tracheotomy, and proportion of recovered patients between the two groups.

CONCLUSIONS

Early rehabilitation is feasible and beneficial to ameliorate diaphragm dysfunction induced by prolonged MV and advance withdrawal from the ventilator and extubation in patients with MV. Diaphragm US is suggested for mechanically ventilated patients in the ICU. Trial registration Chinese Clinical Trial Registry, ID: ChiCTR1900024046, registered on 2019/06/23.

A Novel Normalized Cross-Correlation Speckle-Tracking Ultrasound Algorithm for the Evaluation of Diaphragm Deformation

Objectives: To develop a two-dimensional normalized cross-correlation (NCC)-based ultrasonic speckle-tracking algorithm for right diaphragm deformation analysis.

Methods: Six healthy and eight mechanical ventilation patients were enrolled in this study. Images were acquired by a portable ultrasound system in three sections. DICOM data were processed with NCC to obtain the interframe/cumulative vertical and horizontal displacements, as well as the global strain of the right diaphragm, with continuous tracking and drift correction.

Results: The NCC algorithm can track the contraction and relaxation of the right diaphragm by following the respiratory movement continuously. For all three sections, the interframe and accumulated horizontal displacements were both significantly larger than the corresponding vertical displacements (interframe p values: 0.031, 0.004, and 0.000; cumulative p values: 0.039, 0.001, and <0.0001). For the global strain of the right diaphragm, there was no significant difference between each pair of sections (all p > 0.05), regardless of whether the horizontal interval of the initial diaphragm point was 1, 3, 5, or 10 times in the sampling interval.

Conclusions: This study developed a novel diaphragm deformation ultrasound imaging method. This method can be used to estimate the diaphragm interframe/accumulated displacement in the horizontal and vertical directions and the global strain on three different imaging planes, and it was found that the strain was not sensitive to the imaging plane.