Restoring Functional Status: A Long-Term Case Report of Severe Lung and Ventilatory Muscle Pump Dysfunction Involving Recurrent Bacterial Pneumonias

Background and Purpose: Prolonged mechanical ventilation contributes to immobility and deconditioning making efforts to safely discontinue ventilator support desirable. This case report documents how implementing physical therapy treatment interventions, based on the Guide to Physical Therapist Practice, can help to restore a person’s functional status even after multiple years of mechanical ventilation dependency. Case Description: A patient (female; aged 63 years) with severe restrictive and obstructive ventilatory impairment has survived 34 recurrent pneumonias involving 6 bacterial pathogens while being mechanically ventilated at home. A 3-year study was approved and informed consent obtained for a home exercise program of resistive extremity and inspiratory muscle training along with exercise reconditioning. Tolerable distances walked, maximal inspiratory and expiratory pressures, hours spent on versus off mechanical ventilation, activities performed within and around her home, and community excursions taken were charted. Outcomes: Daily time tolerated off the ventilator improved from less than one to 12 hours, distance walked in 6 minutes increased 33%, and maximal inspiratory and expiratory pressures improved 62% and 9.6% respectively. These improvements made out-of-home social excursions possible. Discussion and Conclusions: This patient’s functional status improved following multiple physical therapy interventions dictated by the evaluation of initial physical therapy examination findings according to the Guide to Physical Therapist Practice. Long term mechanical ventilator dependency in the home environment did not exclude this patient from achieving clinically significant gains in functional status even when having severe restrictive and obstructive ventilator impairment

Inspiratory muscle warm-up does not improve cycling time-trial performance

Purpose: This study examined the effects of an active cycling warm-up, with and without the addition of an inspiratory muscle warm-up (IMW), on 10-km cycling time-trial performance

Sub-cortical and brainstem sites associated with chemo-stimulated increases in ventilation in humans

We investigated the neural basis for spontaneous chemo-stimulated increases in ventilation in awake, healthy humans. Blood oxygen level dependent (BOLD) functional MRI was performed in nine healthy subjects using T2weighted echo planar imaging. Brain volumes (52 transverse slices, cortex to high spinal cord) were acquired every 3.9 s. The 30 min paradigm consisted of six, 5-min cycles, each cycle comprising 45 s of hypoxic-isocapnia, 45 s of isooxic-hypercapnia and 45 s of hypoxic-hypercapnia, with 55 s of non-stimulatory hyperoxic-isocapnia (control) separating each stimulus period. Ventilation was significantly (p < 0.001) increased during hypoxic-isocapnia, isooxic-hypercapnia and hypoxic-hypercapnia (17.0, 13.8, 24.9 L/min respectively) vs. control (8.4 L/min) and was associated with significant (p < 0.05, corrected for multiple comparisons) signal increases within a bilateral network that included the basal ganglia, thalamus, red nucleus, cerebellum, parietal cortex, cingulate and superior mid pons. The neuroanatomical structures identified provide evidence for the spontaneous control of breathing to be mediated by higher brain centres, as well as respiratory nuclei in the brainstem

Noninvasive prediction of Blood Lactate through a machine learning-based approach.

We hypothesized that blood lactate concentration([Lac]blood) is a function of cardiopulmonary variables, exercise intensity and some anthropometric elements during aerobic exercise. This investigation aimed to establish a mathematical model to estimate [Lac]blood noninvasively during constant work rate (CWR) exercise of various intensities. 31 healthy participants were recruited and each underwent 4 cardiopulmonary exercise tests: one incremental and three CWR tests (low: 35% of peak work rate for 15 min, moderate: 60% 10 min and high: 90% 4 min). At the end of each CWR test, venous blood was sampled to determine [Lac]blood. 31 trios of CWR tests were employed to construct the mathematical model, which utilized exponential regression combined with Taylor expansion. Good fitting was achieved when the conditions of low and moderate intensity were put in one model; high-intensity in another. Standard deviation of fitting error in the former condition is 0.52; in the latter is 1.82 mmol/liter. Weighting analysis demonstrated that, besides heart rate, respiratory variables are required in the estimation of [Lac]blood in the model of low/moderate intensity. In conclusion, by measuring noninvasive cardio-respiratory parameters, [Lac]blood during CWR exercise can be determined with good accuracy. This should have application in endurance training and future exercise industry

Personalised mobile services supporting the implementation of clinical guidelines

Telemonitoring is emerging as a compelling application of Body Area Networks (BANs). We describe two health BAN systems developed respectively by a European team and an Australian team and discuss some issues encountered relating to formalization of clinical knowledge to support real-time analysis and interpretation of BAN data. Our example application is an evidence-based telemonitoring and teletreatment application for home-based rehabilitation. The application is intended to support implementation of a clinical guideline for cardiac rehabilitation following myocardial infarction. In addition to this the proposal is to establish the patient’s individual baseline risk profile and, by real-time analysis of BAN data, continually re-assess the current risk level in order to give timely personalised feedback. Static and dynamic risk factors are derived from literature. Many sources express evidence probabilistically, suggesting a requirement for reasoning with uncertainty; elsewhere evidence requires qualitative reasoning: both familiar modes of reasoning in KBSs. However even at this knowledge acquisition stage some issues arise concerning how best to apply the clinical evidence. Furthermore, in cases where insufficient clinical evidence is currently available, telemonitoring can yield large collections of clinical data with the potential for data mining in order to furnish more statistically powerful and accurate clinical evidence

Strength Training Prior to Endurance Exercise: Impact on the Neuromuscular System, Endurance Performance and Cardiorespiratory Responses

This study aimed to investigate the acute effects of two strength-training protocols on the neuromuscular and cardiorespiratory responses during endurance exercise. Thirteen young males (23.2 ± 1.6 years old) participated in this study. The hypertrophic strength-training protocol was composed of 6 sets of 8 squats at 75% of maximal dynamic strength. The plyometric strength-training protocol was composed of 6 sets of 8 jumps performed with the body weight as the workload. Endurance exercise was performed on a cycle ergometer at a power corresponding to the second ventilatory threshold until exhaustion. Before and after each protocol, a maximal voluntary contraction was performed, and the rate of force development and electromyographic parameters were assessed. After the hypertrophic strength-training and plyometric strength-training protocol, significant decreases were observed in the maximal voluntary contraction and rate of force development, whereas no changes were observed in the electromyographic parameters. Oxygen uptake and a heart rate during endurance exercise were not significantly different among the protocols. However, the time-to-exhaustion was significantly higher during endurance exercise alone than when performed after hypertrophic strength-training or plyometric strength-training (p <0.05). These results suggest that endurance performance may be impaired when preceded by strength-training, with no oxygen uptake or heart rate changes during the exercise

Effect of inspiratory pressure support on exercise performance in patients with chronic obstructive pulmonary disease

Title: Effect of inspiratory pressure support on exercise performance in patients with chronic obstructive pulmonary disease. Purpose: This study examined the effects of a non-invasive ventilator on submaximal and maximal exercise performance in patients with chronic obstructive pulmonary disease (COPD). Methods: Fourteen men (66.0 ± 7.4yr) and six women (59.0 ± 7.4yr) with a diagnosis of COPD, a forced expiratory volume! (FEVi) <40%, and the ability to tolerate 12 cmH20 of pressure on a non- invasive ventilator performed two maximal exercise tests on a cycle ergometer, with and without ventilatory assistance prior to exercise. Blood samples, respiratory metabolic measures, heart rate and rating of perceived exertion (RPE) were obtained throughout each exercise test. Results: Peak work rate (W), total exercise time, and respiratory rate were higher (p<0.05) when exercise was preceded by ventilatory support compared to no support. There was no difference in peak oxygen uptake (V02), carbon dioxide (VC02,), heart rate (HR), minute ventilation (VE), tidal volume (VT), blood lactate or RPE between the two experimental conditions. A total of 12 subjects completed at least 5 stages of the exercise protocol, and their physiological response during exercise with NIV and without NIV were compared. RPE was significantly lower during the first 3 min in the NIV condition than the no NIV condition. Circulating levels of blood lactate were lower (p<0.01) during stage 3 in the NIV than the than no NIV condition. There was no difference in RR, VT, HR, %HR, VE, V 0 2and %V02 between the two experimental conditions during sub maximal exercise. Conclusions: Application of non-invasive ventilatory support prior to exercise improves maximal exercise performance, but has no effect on cardio-metabolic response during submaximal exercise in patients with COPD