Criteria For Evaluating Physical And Psychic Dependence And Overall Abuse Potential Of Drugs In Man
S.J. Mulé, Henry Brill in Chemical and Biological Aspects of Drug Dependence, 2019
Scores for accurately measurable signs of abstinence include: Fever: one point for each 0.1° C (rectal) rise.Hyperpnea: one point for each respiration/ minute increase.Systolic blood pressure: one point for each2 mm Hg rise (up to 30 mm).Weight: one point for each pound loss.
The transport and exchange systems: respiratory and cardiovascular
Nick Draper, Helen Marshall in Exercise Physiology, 2014
The onset of exercise stimulates an increase in the depth and rate of breathing, a response that is controlled by the medulla oblongata and the pons (each located in the brain stem). This increase in neural stimulation is thought to result from a combination of simultaneous activation of skeletal muscles and the respiratory centre, psychological stimuli, and signalling from the propriocepters in moving skeletal muscles and joints. The increase in ventilation allows a greater exchange of oxygen and carbon dioxide in the lungs, a crucial response as the skeletal muscle demand for oxygen, and the carbon dioxide production, are increased with exercise. This increase in ventilation due to the enhanced metabolic needs of skeletal muscle is known as hyperpnea.
Metabolic, Degenerative, and Unclassified Conditions Associated With Interstitial Lung Disease
Lourdes R. Laraya-Cuasay, Walter T. Hughes in Interstitial Lung Diseases in Children, 2019
Pathologically, the lungs feel hard and heavy. The shape is well-maintained and the lower lobes appear pale and stony-hard. The lungs are difficult to cut and may need to be sawn. Fixed lung tissue looks like sandpaper. Microscopic examination shows alveoli and bronchioles filled with psammona-like bodies called calcospherites. Electron-microscopy of these calcospherites demonstrate bodies composed of hydroxyapatite crystals. They are laminated and look like “onion skin” granules. Numerous calcifying extracellular matrix vesicles occur between the cells surrounding the mineral deposits, and these resemble the ectopic mineralization which occurs in other diseases. Less damaged parts of the lung show that the calcospherites are deposited in relation to finer blood vessels and vary in diameter from 0.1 to 0.3 mm to as large as about 1 mm. Chemical analysis reveals calcium, phosphorus, mainly phosphates, small amount of iron, and traces of magnesium. Sudanophilic and doubly refractile fatty material have appeared in frozen sections. The calcospherites have to be differentiated from corpora amylacea which occur commonly in conditions with heart failure, chronic bronchitis, and pulmonary infarction. Extrapulmonary changes include findings compatible with cor pulmonale. Hypoxemia studies demonstrate reduced vital capacity which progressively declines as the condition becomes prolonged. Arterial oxygen desaturation occurs late in the disease when more alveoli are involved. Hyperpnea is seen in the later stages at a time when lung compliance changes are more pronounced.87
Spinal cord injury and diaphragm neuromotor control
Published in Expert Review of Respiratory Medicine, 2020
Matthew J. Fogarty, Gary C. Sieck
The indefatigable requirement for tidal breathing necessitates the generation of non-fatiguing Pdi, at a high duty cycle (time active versus inactive) approaching 40% [4,5] that is sustained for the entirety of one’s life. This is achieved via the generation of small negative intrathoracic pressures (Pth) resulting from relatively moderate caudal excursions of the diaphragm muscle [6,7]. Typically, expiration is passive during eupnea, driven by the elastic recoil of the lungs and chest wall that generate a positive Pab [6]. The Pdi necessary for ventilation of the lung is generally around 15% of Pdimax during eupnea and approaches 30–40% Pdimax during maximal ventilatory efforts against an occluded airway [3–5,8]. Indeed, during maximum voluntary hyperpnea with controlled CO2, Pdi does not exceed 60% Pdimax [9,10]. Thus, ventilatory requirements for diaphragm muscle activation are submaximal with considerable reserve capacity for force generation.
The feasibility of eucapnic voluntary hyperpnoea for the diagnosis of exercise-induced bronchoconstriction in a community pulmonary practice
Published in Journal of Asthma, 2022
Brandon Temte, Jason Wells, Crystal Clark, Jordan Lauw, John Mastronarde
Baseline spirometry was performed according to the American Thoracic Society standards (15). Patients were then instructed to breathe a mixture of dry compressed gas (5.0% CO2, 21.0% O2, and N2 balance content) in timed, rapid, deep breaths. The target rate was 85% of their maximum voluntary ventilation (MVV) per minute (calculated as 30 x baseline FEV1) for six minutes. For an EVH test to be considered adequate, the average minute ventilation over the six-minute testing period had to be >60% MVV (calculated as 21 x baseline FEV1). The gaseous mixture was channeled from a tank through the reservoir bag. The gas mixture then traveled through tubing and a two-way, low-resistance Hans Rudolph valve followed by the patient’s mouthpiece. A metronome was timed for 30 cycles per minute to assist the patient in achieving their target MVV. Spirometry was then performed at 3, 5, 10, 15, and 20 min post-hyperpnea challenge. All patients were monitored with continuous pulse oximetry throughout the hyperpnea challenge with maximal, average, and minimal SpO2 and heart rate recorded.
Fat mass index and airway hyperresponsiveness in Korean adults
Published in Postgraduate Medicine, 2023
Ji-Su Shim, Sun-Sin Kim, So-Hee Lee, Min-Hye Kim, Young-Joo Cho, Heung-Woo Park
This study had a few limitations. First, the study participants underwent health checkups at single center, which may have introduced selection bias. Participants who engage in unhealthy behaviors such as smoking may choose to receive additional tests like as MBPT, which may have introduced bias into the study results. Second, we could not completely exclude reasons for a false-positive result for MBPT such as respiratory infection [40]. In addition, we measured only direct AHR based on MBPT. Indirect challenges including exercise, eucapnic voluntary hyperpnea, hypertonic saline, or mannitol could identify additional individuals with AHR, as they are complementary to direct challenges and reflect active airway inflammation [41]. Third, we did not measure the serum levels of adipokines such as adiponectin and leptin which play important roles in the pathological changes in obese patients. Finally, we include a small number of participants. Only about 4% of participants developed AHR during follow-up. Due to the scarcity of previous studies, it is unclear whether or not this conversion rate is accurate. These limitations should be considered when interpreting our results.