Effect of early intensive rehabilitation on the clinical outcomes of patients with acute stroke.

AIM: Intensive rehabilitation effectively improves physical functions in patients with acute stroke, but the frequency of intervention and its cost-effectiveness are poorly studied. This study aimed to examine the effect of early high-frequency rehabilitation intervention on inpatient outcomes and medical expenses of patients with stroke. METHODS: The study retrospectively included 1759 patients with acute stroke admitted to the Kobe City Medical Center General Hospital between 2013 and 2016. Patients with a transient ischemic attack, subarachnoid hemorrhage, and those who underwent urgent surgery were excluded. Patients were divided into two groups according to the frequency of rehabilitation intervention: the high-frequency intervention group (>2 times/day, n = 1105) and normal-frequency intervention group (<2 times/day, n = 654). A modified Rankin scale score ≤2 at discharge, immobility-related complications and medical expenses were compared between the groups. RESULTS: The high-frequency intervention group had a significantly shorter time to first rehabilitation (median [interquartile range], 19.0 h [13.1-38.4] vs. 24.7 h [16.1-49.4], P < 0.001) and time to first mobilization (23.3 h [8.7-47.2] vs. 22.8 h [5.7-62.3], P = 0.65) than the normal-frequency intervention group. Despite higher disease severity, the high-frequency intervention group exhibited favorable outcomes at discharge (modified Rankin scale, ≤2; adjusted odds ratio, 1.89; 95% confidence interval, 1.25-2.85; P = 0.002). No significant differences were observed between the two groups concerning the rate of immobility-related complications and total medical expenses during hospitalization. CONCLUSIONS: High-frequency intervention was associated with improved outcomes and decreased medical expenses in patients with stroke. Our results may contribute to reducing medical expenses by increasing the efficiency of care delivery. Geriatr Gerontol Int 2021; 21: 623-628.

Effects of increased respiratory rate on cortical oxygenated hemoglobin during low-intensity exercise.

This study aimed to examine whether the end-tidal partial pressure of CO2 (PEtCO2) affects the concentration of oxygenated hemoglobin (O2Hb) measured by near-infrared spectroscopy (NIRS). Participants were examined under the conditions of normal and increased ventilation. We measured O2Hb, mean blood pressure, skin blood flow, PEtCO2, respiratory rate, and minute volume at 30 % of the maximum oxygen uptake during exercise. ΔO2Hb and PEtCO2 during exercise were lower in the increased ventilation than in the normal ventilation condition. Pearson's product-moment correlation analysis showed a significant positive correlation between ΔO2Hb and ΔMAP, ΔSBF, and PEtCO2. Correlation coefficients were 0.249 (p < 0.001) for ΔMAP, 0.343 (p < 0.001) for ΔSBF, and 0.315 (p < 0.001) for PEtCO2. In conclusion, we identified increased ventilation during bicycle ergometer exercise as a significant factor associated with significantly low PEtCO2 and ΔO2Hb.

Low Muscle Mass is Associated with Walking Function in Patients with Acute Ischemic Stroke.

BACKGROUND: Muscle mass might be a possible predictor for walking function in patients with stroke; however, evidence is limited. OBJECTIVE: To investigate whether skeletal muscle mass is associated with walking function at discharge during the acute phase. METHODS: In this observational cohort study, we assessed skeletal muscle mass in patients with acute ischemic stroke using the noninvasive and portable multifrequency bio-impedance device. This device can easily be used in bedridden patients. Appendicular skeletal muscle mass was converted to skeletal muscle index (SMI) standardizing by height squared (kg/m2). The primary outcome was walking function assessed by the modified Rankin Scale score at acute phase hospital discharge. Logistic regression analysis was used to determine the association between skeletal muscle mass and walking function. RESULTS: Of the 107 patients enrolled, low SMI (SMI: male <7.0 kg/m2, female <5.7 kg/m2) was identified in 29.9% (19.7% in men, 48.6% in women). Logistic regression analysis showed that low SMI [OR: 4.02, 95% confidence interval (CI): 1.38-11.7, p = 0.001] independently associated with walking function at discharge. Further, patients with mild and moderate severity had significant difficulty in walking when they had low SMI (p = 0.039). CONCLUSIONS: Low skeletal muscle mass at the onset of ischemic stroke is an independent predictor of walking function at discharge during the acute phase. Our findings highlight the importance of detecting skeletal muscle mass in patients with acute ischemic stroke.

Preoperative physical performance-related postoperative delirium in patients after cardiovascular surgery.

OBJECTIVES: This investigation clarified the relationship between a short physical performance battery (SPPB) that can comprehensively and safely evaluate balance function, walking ability, lower limb muscle strength, and postoperative delirium. METHODS: This was a retrospective observational study performed at Kobe City Medical Center General Hospital. Patients who underwent surgery at the Kobe City Medical Center General Hospital Cardiovascular Surgery from August 1, 2016 to July 31, 2017 were included. Preoperative physical functions were obtained. Those showing positive results using the confusion assessment method for intensive care unit (ICU) during the ICU stay were considered as the delirium group, and the postoperative and non-postoperative delirium groups were compared. A multiple logistic regression analysis was performed with the presence or absence of onset of delirium as the dependent variable and the SPPB total score and age as dependent variables. RESULTS: There were 193 subjects in this study (120 males and 73 females). Sixteen patients (8.4 %) had postoperative delirium. The age in the postoperative delirium group was significantly higher than in the postoperative delirium group (77.8 (7.0) years vs. 70.0 (11.1) years). BMI and SPPB total score were significantly lower in the postoperative delirium group. From the multiple logistic regression, the SPPB total score (OR: 0.754, 95 % CI: 0.643-0.883, p < 0.001) was extracted as a factor related to postoperative delirium onset. CONCLUSION: It was illuminated that in patients with cardiovascular surgery, preoperative low physical function was not affected by age and became a risk factor of postoperative delirium onset.

Correlation Between the Cerebral Oxyhaemoglobin Signal and Physiological Signals During Cycling Exercise: A Near-Infrared Spectroscopy Study.

Near-infrared spectroscopy (NIRS) is a widely used noninvasive method for measuring human brain activation based on the cerebral haemodynamic response. However, systemic changes can influence the signal's parameters. Our study aimed to investigate the relationships between NIRS signals and skin blood flow (SBF) or blood pressure during dynamic movement. Nine healthy volunteers (mean age, 21.3 ± 0.7 years; 6 women) participated in this study. The oxyhaemoglobin (O2Hb) signal, SBF, and mean arterial pressure (MAP) were measured while the volunteers performed multi-step incremental exercise on a bicycle ergometer, at workloads corresponding to 30, 50, and 70 % of peak oxygen consumption (VO2peak) for 5 min. The Pearson's correlation coefficients for the O2Hb signal and SBF at 50 and 70 % VO2peak were 0.877 (P < 0.01) and -0.707 (P < 0.01), respectively. The correlation coefficients for O2Hb and MAP during warm-up, 30 % VO2peak, and 50 % VO2peak were 0.725 (P < 0.01), 0.472 (P < 0.01), and 0.939 (P < 0.01), respectively. Changes in the state of the cardiovascular system influenced O2Hb signals positively during low and moderate-intensity exercise, whereas a negative relationship was observed during high-intensity exercise. These results suggest that the relationship between the O2Hb signal and systemic changes is affected by exercise intensity.

Effect of Locomotor Respiratory Coupling Induced by Cortical Oxygenated Hemoglobin Levels During Cycle Ergometer Exercise of Light Intensity.

This study aimed to clarify the effects of locomotor-respiratory coupling (LRC) induced by light load cycle ergometer exercise on oxygenated hemoglobin (O2Hb) in the dorsolateral prefrontal cortex (DLPFC), supplementary motor area (SMA), and sensorimotor cortex (SMC). The participants were 15 young healthy adults (9 men and 6 women, mean age: 23.1 ± 1.8 (SEM) years). We conducted a task in both LRC-inducing and LRC-non-inducing conditions for all participants. O2Hb was measured using near-infrared spectroscopy. The LRC frequency ratio during induction was 2:1; pedaling rate, 50 rpm; and intensity of load, 30 % peak volume of oxygen uptake. The test protocol included a 3-min rest prior to exercise, steady loading motion for 10 min, and 10-min rest post exercise (a total of 23 min). In the measurement of O2Hb, we focused on the DLPFC, SMA, and SMC. The LRC frequency was significantly higher in the LRC-inducing condition (p < 0.05). O2Hb during exercise was significantly lower in the DLPFC and SMA, under the LRC-inducing condition (p < 0.05). The study revealed that even light load could induce LRC and that O2Hb in the DLPFC and SMA decreases during exercise via LRC induction.

Effect of Transcranial Direct Current Stimulation over the Primary Motor Cortex on Cerebral Blood Flow: A Time Course Study Using Near-infrared Spectroscopy.

Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique that is applied during stroke rehabilitation. The purpose of this study was to examine diachronic intracranial hemodynamic changes using near-infrared spectroscopy (NIRS) during tDCS applied to the primary motor cortex (M1). Seven healthy volunteers were tested during real stimulation (anodal and cathodal) and during sham stimulation. Stimulation lasted 20 min and NIRS data were collected for about 23 min including the baseline. NIRS probe holders were positioned over the entire contralateral sensory motor area. Compared to the sham condition, both anodal and cathodal stimulation resulted in significantly lower oxyhemoglobin (O2Hb) concentrations in the contralateral premotor cortex (PMC), supplementary motor area (SMA), and M1 (p<0.01). Particularly in the SMA, the O2Hb concentration during anodal stimulation was significantly lower than that during the sham condition (p<0.01), while the O2Hb concentration during cathodal stimulation was lower than that during anodal stimulation (p<0.01). In addition, in the primary sensory cortex, the O2Hb concentration during anodal stimulation was significantly higher than the concentrations during both cathodal stimulation and the sham condition (p<0.05). The factor of time did not demonstrate significant differences. These results suggest that both anodal and cathodal tDCS cause widespread changes in cerebral blood flow, not only in the area immediately under the electrode, but also in other areas of the cortex.