Cardiorespiratory Index Research Articles

Influences of Cardiorespiratory Fitness and Body Mass Index on All-Cause Mortality

Influences of Cardiorespiratory Fitness and Body Mass Index on All-Cause Mortality

Sub-Tenon's local anaesthesia for the treatment of retinopathy of prematurity with diode laser

To evaluate the safety and efficacy of sub-Tenon's local anaesthesia (LA) for laser treatment of threshold retinopathy of prematurity (ROP). A cohort of 18 eyes of 10 neonates with threshold ROP was treated with diode laser peripheral retinal ablation over 14 treatment sessions using oral sedation and sub-Tenon's anaesthesia. Treatment was performed in a neonatal unit. The heart and respiratory rate, trans-cutaneous oxygen saturation, and physical activity were continuously monitored for signs of neonatal distress. Cardio-respiratory stability during and after the procedure was scored for each eye treated using a Cardio-respiratory index described previously. In all cases, the planned dose of laser was delivered. One out of 18 eyes developed stage 4b tractional retinal detachment over a follow-up of at least 6 months for all babies. Systemic complications during treatment included transient bradycardia and apnoea requiring stimulation in two babies and excessive head mobility in three babies. Treatment duration varied between 20 and 80 min. Ocular complications were conjunctival haemorrhage and chemosis. The mean cardio-respiratory index was 1.13, which compared favourably with the standard published. Sub-Tenon's LA with oral sedation appears to be a safe and effective alternative to general anaesthesia for laser treatment of ROP, with the potential for lower morbidity.

Altered cardiorespiratory transfer in hypertension.

The effect of continuously slowing respiration (from 0.46 to 0.05 Hz, eg, from 30 to 3 breaths per minute) on cardiovascular variables was studied in 14 hypertensive patients and 16 normotensive subjects. Beat-to-beat time-frequency (Wigner) distributions were used for dynamic analysis of RR interval and systolic and diastolic pressures. Dominant breathing frequency at rest did not differ in hypertensive patients from the control group (0.21 versus 0.19 Hz). However, in the hypertensive group it was disturbed 34.4% of the time by slow breathing and apneas, which evoked transient blood pressure instability and increased spectral powers at low frequencies (range, 0.01 to 0.1 Hz). The nonrespiratory fluctuations (NONRFs) and respiratory fluctuations (RFs) in RR interval and NONRFs in systolic pressure were smaller in hypertensive patients (P < .001). In both groups, slowing of respiratory frequency from 0.46 to 0.05 Hz entrained RFs in the RR interval and systolic and diastolic pressures. RFs in the RR interval remained diminished in hypertensive patients (P < .001), but RFs in systolic pressure increased higher at maximum, corresponding to breathing frequencies from 0.07 to 0.09 Hz (P < .001). A dynamic cardiorespiratory index (ratio of RFs in RR interval and systolic pressure) was smaller (P < .01) in hypertensive patients than in normotensive subjects. Irregular breathing at rest was found in hypertensive patients. The transfer from respiration into RR interval was diminished, suggesting an impaired parasympathetic responsiveness in mild hypertension.

Effect of swimming on increasing of cardiorespiratory capacity in paraplegics

The aim of this paper was to study the effect of swimming training on the cardio-respiratory system of paraplegics. The observation of 60 paraplegics (34 males and 26 females) was carried out during the three years experiment. To measure a cardio-respiratory efficiency level we used Skibinski's cardio-respiratory index (SCRI). After three years of the swimming training programme the SCRI value increased four times.