Biomedical subjects

C J Kelsey

Publications and source records attributed to C J Kelsey.

3 recordsLinked to original sources

PubMed1992

Changes in ventilation in response to ramp changes in treadmill exercise load.

These experiments examined the changes in ventilation during a 40-s ramp increase in exercise load, produced by increasing either the speed of the treadmill or the grade, to equivalent end-points of oxygen uptake. Six subjects underwent five trials each for grade and speed, while ventilation was monitored breath-by-breath. For each subject, ventilation versus time for all five of the speed trials was plotted on a single graph and fitted by linear regression. The data for the grade trials were similarly treated. For all subjects, the slope of the regression line for the speed plots was found to be significantly (P < 0.05) greater than that for the grade plots. We concluded that these experimental results support the hypothesis that the neural drive to ventilation persists as exercise continues and is proportionately related to the frequency of limb movement.

Adult↗

PubMed1987

The effect of treadmill speed on ventilation at the start of exercise in man.

1. The change in ventilation at the start of exercise was determined during both hyperoxic rebreathing and air breathing in four volunteers. 2. In order to differentiate between the effects of limb-movement frequency and exercise load in terms of oxygen uptake, three treadmill exercises were tested: E1, at an oxygen uptake of 1 l/min on a level treadmill; E2, at 2 l/min on an inclined treadmill at the same speed as E1; E3, at 2 l/min on a level treadmill at a higher speed. All of the exercises were performed at a walking pace. 3. Prior to rebreathing, hyperventilation for 5 min to 20 mmHg was used to reduce carbon dioxide to below the central chemoreceptor threshold. From eleven to fourteen rebreathing experiments were done on each volunteer for each of the three exercises, with the treadmill started at carbon dioxide levels which ranged from 36 (below threshold) to 58 mmHg (above threshold). 4. Ten experiments were performed on each volunteer for each of the three exercises during air breathing, with the treadmill started after 5 min of rest. 5. In both the rebreathing experiments and the air breathing experiments it was found that the change in ventilation at the start of exercise was the same for exercises E1 and E2, and significantly greater for exercise E3. 6. It was concluded that the frequency of limb movement, rather than exercise load (oxygen consumption) is a determinant of the change in ventilation at the start of exercise.

Adult↗

PubMedDate not supplied

Clinical practice guidelines for suctioning the airway of the intubated and nonintubated patient.

OBJECTIVE: To provide physicians, physiotherapists, nurses and respiratory therapists with guidelines for the application of airway suctioning. DESIGN: This clinical practice guideline was developed using the model by Browman and colleagues. A working group of representatives from four professional colleges (nurses, physicians and surgeons, physiotherapists and respiratory therapists) and research experts was formed to conduct a systematic review, develop evidence-based recommendations and generate clinical practice guidelines. MEDLINE (1966 to 1998), CINAHL (1982 to 1997) and EMBASE (1974 to 1996) as well as the reference lists of identified articles were searched. Inclusion of articles was determined by at least two group members, and studies were classified according to type. Randomized, controlled; randomized; and nonrandomized crossover and comparative cohort trials were grouped by type of intervention and population for use in the development of recommendations. Other observational and animal studies dealing with adverse effects of suctioning were included in the review but were not used in the development of recommendations. Input on the evidence-based recommendations was sought and incorporated from members of all four professions and from experts on content and methodology. SETTING: Any setting (hospital or home) where suctioning is performed. POPULATION: Intubated and nonintubated adults, infants and children. RESULTS AND CONCLUSIONS: An attempt was made to develop recommendations in each of the subcategories of suctioning techniques addressed by at least one study. In some subcategories, definite recommendations were made (13 in adults, and three in children and infants); in other subcategories, insufficient evidence precluded recommendations. The recommendations addressed the following aspects of suctioning: preoxygenation, hyperinflation, insufflation, hyperoxygenation, hyperventilation, saline instillation, adaptor use, medication use, open and closed systems, and various types of catheters.

Adult↗