Jun Ueki

Size and strength of the respiratory and quadriceps muscles in patients with chronic asthma

There have been few studies of respiratory and limb muscle size and function in middle-aged patients with asthma and persistent airways obstruction. We have compared the forces generated by the respiratory and thigh muscles with their dimensions assessed by ultrasound in nine middle-aged patients with chronic asthma (mean age 56 (SD 8) yrs; functional residual capacity/total lung capacity ratio (FRC/TLC) 60 (10)%), and in nine normal subjects (aged 53 (7) yrs; FRC/TLC 55 (5)%). Diaphragm thickness was measured at the zone of apposition by B-mode ultrasound during relaxation (DiTrelax) and during a maximum-effort inspiratory manoeuvre (DiTpI,max) at FRC. Cross-sectional area of the relaxed rectus femoris muscle (ARF) was determined by ultrasound at mid-thigh level. Isometric strength of the right quadriceps muscle group was measured during maximum voluntary contraction. Asthmatic patients had preserved quadriceps strength and ARF but moderately impaired maximum inspiratory pressure (PI,max) (-52 (18) cmH2O) and thicker DiTrelax (2.2 (0.4) mm), compared to normal subjects (-73 (21) cmH2O and 1.7 (0.3) mm, respectively). Middle-aged patients with chronic asthma and a small increase in functional residual capacity/total lung capacity ratio have preserved limb muscle force and dimensions, modestly impaired inspiratory muscle strength, and slightly increased thickness of the costal diaphragm. Future studies of respiratory muscle function in asthma should be aided by measurement of diaphragm thickness and of limb muscle strength and size. Such studies are required particularly in older patients with severe hyperinflation who are most likely to have impairment of muscle function.

Oxygen and 99mTc-MAA shunt estimations in patients with pulmonary arteriovenous malformations: effects of changes in posture and lung volume.

BACKGROUND--Patients with arteriovenous malformations are routinely monitored with arterial oxygen saturation (SaO2) estimations (breathing air) from which an oxygen shunt fraction can be calculated. This simple estimation has been compared with an anatomically defined estimate of the right to left shunt using a radioisotopic method. The fall in SaO2 which occurs in patients with pulmonary arteriovenous malformations in the erect posture and at high lung volumes was used to test the ability of SaO2 alone to follow changes in right to left shunt. METHODS--Radiolabelled albumin macroaggregates (99mTc-MAA) or microspheres (MS) were injected intravenously and kidneys and lungs were imaged. The shunt fraction (QS/QTTc) in the supine position at functional residual capacity (baseline) was obtained by quantifying right kidney radioactivity. On standing or while breath holding at total lung capacity, shunt fraction was calculated from baseline QS/QTTc and from lung counts and the injected dose. Arterial oxygen saturation (SaO2) was recorded by a pulse oximeter for calculation of the oxygen shunt (QS/QTO2) (breathing air). RESULTS--In the postural study (n = 8) SaO2 decreased from a mean (SD) value of 89 (5)% supine to 80 (6)% erect, corresponding to QS/QTO2 28 (8)% and 44 (8)% respectively. QS/QTTc increased from 28.7 (10.3)% to 39 (14.3)%. In the lung volume study (n = 8) QS/QTTc increased from 16.6 (11.5)% at functional residual capacity to 23.3 (11.9)% at total lung capacity while QS/QTO2 increased from 19.5 (7.5)% to 25.9 (10.6)% respectively. When all measurements were compared for QS/QTTc% and QS/QTO2% (n = 32) the difference in the mean values was 2.5% (absolute) and the limits of agreement between the two methods were +38% to -18% (relative). In neither the postural nor the volume study did delta (QS/QTO2) reliably predict delta (QS/QTTc)%. CONCLUSIONS--In pulmonary arteriovenous malformations the simple physiological shunt calculated from SaO2 breathing air agreed well with the anatomical right to left shunt measured with 99mTc-MAA, but predicted poorly the changes in anatomical shunt induced by postural or lung volume changes.

Ultrasonographic evaluation of the diaphragm in patients with amyotrophic lateral sclerosis.

Abstract:  Real‐time diaphragmatic movement was evaluated with ultrasonography in three patients with amyotrophic lateral sclerosis (ALS). The initial complaint of two patients was weakness of the extremities followed by dyspnoea later in the disease course, while the third patient had dyspnoea as the initial symptom. Ultrasonographic analyses revealed that the contractile function of the diaphragm was not maintained during maximum inspiratory effort, with unsatisfactory diaphragmatic excursion and no change in diaphragmatic thickness during respiration, indicating diaphragmatic paralysis. Ultrasonography may be useful for the diagnosis and follow up of diaphragmatic involvement with amyotrophic lateral sclerosis and other motor‐neuron diseases.

Transoesophageal ultrasonography in the staging of lung cancer

In primary lung cancer, tumour extent is generally the most important determinant in the selection of therapy [6,42]. There is a growing tendency to stage this disease with the TNM classification, in which “T” means location and size of the primary lesion, “N”, lymph node involvement of the hilum and mediastinum, and “M”, the presence or absence of distant metastasis [6,35]. Epidemiological surveys based on the TNM classification show an excellent correlation between this staging and survival rate [20,35]. Most patients who have T4, N3 and/or Ml lesions are usually not considered surgical candidates [6,19]. With N2 lesions, it is reported that radical node dissection can cure a significant percentage of patients or prolong their survival rate [19,21,30,39]. T3 patients may be resectable, but surgical management of these lesions is controversial [19,25,30]. In summary, lung resection should not be performed in patients in whom the tumour cannot be completely removed; however, it is also essential not to preclude potentially curative surgery due to overstaging. Therefore the selection of the correct treatment in each patient depends on exact staging [ 13,421. High resolution and real-time sonographic scanning not only permits observation of relative movement of lesions and neighbouring structures, but also provides information about the characteristics of tissues such as differentiation of the vessels from solid masses [11,24,29,33,37,38]. However, the value of ultrasonography for the evaluation of the mediastinum is limited by bones and air. To solve this problem, transoesophageal endoscopic

Efficacy of tiotropium/olodaterol on lung volume, exercise capacity, and physical activity

Purpose This study evaluated the efficacy of tiotropium/olodaterol vs tiotropium on lung function, exercise capacity, and physical activity in patients with COPD. Patients and methods A total of 184 patients aged ≥40 years with COPD (Global Initiative for Chronic Obstructive Lung Disease stage II–IV) received tiotropium/olodaterol for 6 weeks, then tiotropium for 6 weeks, or vice versa. The primary endpoint was inspiratory capacity (IC) at peak post-dose. Results Adjusted mean IC after 6-week treatment was 1.990 L with tiotropium/olodaterol vs 1.875 L with tiotropium (difference: 115 mL; 95% CI: 77, 153; p<0.0001). Forced expiratory volume in 1 s (difference: 105 mL; 95% CI: 88, 123), forced vital capacity (difference: 163 mL; 95% CI: 130, 197), and slow vital capacity (difference: 134 mL; 95% CI: 91, 176) improved with tiotropium/olodaterol (all p<0.0001). Adjusted mean 6-min walk distance was similar between treatments in the overall population but was significantly increased with tiotropium/olodaterol in the subgroup with Global Initiative for Chronic Obstructive Lung Disease stage III/IV at baseline (difference: 18.1 m; 95% CI: 2.3, 33.9; p=0.0254). In a post hoc analysis, tiotropium/olodaterol improved the values for ≥2.0 metabolic equivalents (difference: 5.0 min; 95% CI: 0.4, 9.7; p=0.0337). Conclusion Tiotropium/olodaterol significantly improved IC compared with tiotropium and potentially enhanced the exercise capacity in COPD patients. A slight improvement in physical activity of relatively more than moderate intensity was also seen with tiotropium/olodaterol.

Toward the harmonization of work with treatment and prevention for patients with chronic respiratory failure

Home oxygen therapy (HOT), also known as long-term oxygen therapy, is prescribed to patients with chronic respiratory failure (CRF) due to advanced respiratory diseases, as it has been shown to improve the prognosis of patients with chronic obstructive pulmonary disease (COPD). However, the therapeutic impact of HOT does not fully reflect the “socialization” of patients, which is one of the final goals of “comprehensive pulmonary rehabilitation”, proposed by the Japanese Respiratory Society. Since working is one form of socialization, we evaluated a 55-yr-old worker prescribed with HOT for the management of advanced COPD to elucidate and assess the social barriers experienced by HOT users. This case demonstrates a variety of factors affecting patients, respiratory physicians, occupational physicians, and management teams, which prevents patients from working. By elucidating these factors and seeking solutions, the promotion of the “harmonization of work with treatment and prevention” will both improve working environments and encourage CRF patients to continue working, leading to better socialization. Thus, the “harmonization of working with treatment and prevention” for CRF patients is a core goal for the promotion of both “health and productivity management” and “comprehensive pulmonary rehabilitation.”