Association of Diaphragm Thickness and Respiratory Muscle Strength With Indices of Sarcopenia.

OBJECTIVE: To evaluate the relationship between respiratory muscle strength, diaphragm thickness (DT), and indices of sarcopenia. METHODS: This study included 45 healthy elderly volunteers (21 male and 24 female) aged 65 years or older. Sarcopenia indices, including hand grip strength (HGS) and body mass index-adjusted appendicular skeletal muscle (ASM/BMI), were measured using a hand grip dynamometer and bioimpedance analysis, respectively. Calf circumference (CC) and gait speed were also measured. Maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) were obtained using a spirometer, as a measure of respiratory muscle strength. DT was evaluated through ultrasonography. The association between indices of sarcopenia, respiratory muscle strength, and DT was evaluated using Spearman's rank correlation test, and univariate and multiple regression analysis. RESULTS: ASM/BMI (r=0.609, p<0.01), CC (r=0.499, p<0.01), HGS (r=0.759, p<0.01), and gait speed (r=0.319, p<0.05) were significantly correlated with DT. In the univariate linear regression analysis, MIP was significantly associated with age (p=0.003), DT (p<0.001), HGS (p=0.002), CC (p=0.013), and gait speed (p=0.026). MEP was significantly associated with sex (p=0.001), BMI (p=0.033), ASM/BMI (p=0.003), DT (p<0.001), HGS (p<0.001), CC (p=0.001) and gait speed (p=0.004). In the multiple linear regression analysis, age (p=0.001), DT (p<0.001), and ASM/BMI (p=0.008) showed significant association with MIP. DT (p<0.001) and gait speed (p=0.050) were associated with MEP. CONCLUSION: Our findings suggest that respiratory muscle strength is associated with DT and indices of sarcopenia. Further prospective studies with larger sample sizes are needed to confirm these findings.

Development and Evaluation of a New Chest Compression Technique for Cardiopulmonary Resuscitation in Infants.

We designed the newly developed flexed two-finger chest compression technique for cardiopulmonary resuscitation (CPR) in infants to increase the quality of chest compression by considering the advantages and disadvantages of the two-thumb encircling hand technique and conventional two-finger technique. The aim of the study is to compare the performance of the flexed two-finger technique and the currently used two-thumb technique or two-finger technique for infant CPR. A total of 42 doctors conducted 2-min single-rescuer CPR on a cardiac arrest infant model using the two-thumb technique followed, in a random order, by the two-finger technique and the flexed two-finger technique. Although the ratio of the adequate compression depth was highest in the two-thumb technique, followed by the flexed two-finger technique and two-finger technique (100% [98-100] vs. 99% [80-100] vs. 76% [42-95], respectively, P < 0.001), the hand-off time of the two-thumb technique was significantly longer than in the two-finger technique and flexed two-finger technique (31 s [28-35] vs. 29 s [27-32] vs. 29 s [26-32], respectively, P < 0.001). The number of total chest compressions of the two-thumb technique was significantly lower than in the two-finger technique and flexed two-finger technique (150 [148-159] vs. 159 [149-173] vs. 162 [150-172], respectively, P < 0.001). The newly developed chest compression technique could provide adequate compression depth without increasing the hand-off time during single-rescuer infant CPR.Trial registration: Clinical Research Information Service, KCT0002730.

Sustained disconnection in sensorimotor pathways results in poor motor function outcome in a term infant after severe white matter injury: A case report.

INTRODUCTION: We report a case of an infant with severe white matter injury (WMI), which was serially evaluated using diffusion tensor imaging (DTI). CASE PRESENTATION: A male infant showed decreased muscle tone and weak breathing. A brain magnetic resonance imaging (MRI) 10 days after birth (first study) revealed diffuse microhemorrhages and encephalomalacia. DTI revealed lack of reconstruction of corticospinal tract (CSTs), minimal reconstruction of medial lemniscus, and related thalamocortical pathways (MLs) from the brain stem to the internal capsule level on the left side. The spinothalamic tract and related thalamocortical pathways (STTs) were reconstructed from the brain stem to the internal capsule level bilaterally. The second study one year later showed the absence of reconstruction of CSTs, but reconstruction of MLs and STTS from the brain stem to above the internal capsule showed increased visualization. The third study 3 years later still showed the absence of CSTs reconstruction and MLs and STTs showed no changes from the second study. During this 3-year observation period, the patient showed minimal motor development, and was unable to walk independently, although Gross Motor Function Measure (GMFM) scores were slightly increased. LESSONS: Sustained disconnection of major sensorimotor pathways after WMI confirmed by DTI was used to predict motor function outcome.

The superiority of the two-thumb over the two-finger technique for single-rescuer infant cardiopulmonary resuscitation.

OBJECTIVES: The two-finger technique (TFT) using the index-middle fingers of the right hand (TFT-R23) was recently confirmed to produce deeper chest compression depth (CCD) compared with the TFT using any other fingers. This study was carried out to confirm whether the TFT-R23 would be as effective as the two-thumb technique (TTT). In addition, individual finger strengths were measured to identify the reasons why the TTT and TFT-R23 produced deeper CCD than any other methods. METHODS: This prospective randomized cross-over trial compared TTT with TFT-R23. A total of 37 doctors conducted 2 min single-rescuer cardiopulmonary resuscitation using TTT and TFT-R23 in a random order using a 3-month-old sized infant manikin laid on the floor. The chest compression to ventilation ratio was set to 15 : 2. In addition, finger strengths were measured using a pinch meter. RESULTS: The actual CCD of the TTT was significantly deeper than that of the TFT-R23 (41.3±1.3 vs. 39.8±1.5 mm, P<0.001). Although the hands-off time of the TTT was significantly longer than that of the TFT-R23 (55.6±5.7 vs. 53.6±5.8 s, P=0.002), the mean difference was only 2.0±3.7 s (95% confidence interval: 0.755-3.245). The finger strength of the TTT was significantly higher than that of TFT-R23 (23.8±10.1 vs. 13.7±5.1 kg, P<0.001). CONCLUSION: The TTT produced deeper CCD compared with that of the TFT-R23 because the finger strength of the TTT was significantly higher than that of the TFT-R23.

Relation Between Respiratory Muscle Strength and Skeletal Muscle Mass and Hand Grip Strength in the Healthy Elderly.

OBJECTIVE: To evaluate sarcopenic indices in relation to respiratory muscle strength (RMS) in elderly people. METHODS: This study included 65 volunteers over the age of 60 (30 men and 35 women). The skeletal muscle mass index (SMI) was measured using bioimpedance analysis. Limb muscle function was assessed by handgrip strength (HGS), the Short Physical Performance Battery (SPPB), and gait speed. RMS was addressed by maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) using a spirometer. The relationships between RMS and other sarcopenic indices were investigated using the Pearson correlation coefficients and multiple regression analysis adjusted for age, HGS, and SPPB. RESULTS: Both MIP and MEP were positively correlated with SMI (r=0.451 and r=0.388, respectively, p<0.05 in both). HGS showed a significant correlation with both MIP and MEP (r=0.560, p<0.01 and r=0.393, p<0.05, respectively). There was no significant correlation between gait speed and either MIP or MEP. The SPPB was positively correlated with MEP (r=0.436, p<0.05). In the multiple regression analysis, MIP was significantly associated with HGS and SMI (p<0.001 and p<0.05, respectively), while MEP was related only with HGS (p<0.05). CONCLUSION: This study suggests that respiratory muscles, especially inspiratory muscles, are significantly related to limb muscle strength and skeletal muscle mass. The clinical significance of MIP and MEP should be further investigated with prospective studies.