Long-term profiles of sleep-related hemodynamic changes in the postoperative chronic cat

The long-term postoperative changes in mean arterial pressure (MAP) and heart rate (HR) during sleep in cats (n = 4) were observed. In the first or second week after surgery, MAP and HR in slow wave sleep (SS) just prior to paradoxical sleep (PS) were higher than those in PS as described in previous reports. In the fourth or fifth week after surgery, the above relationships of MAP and HR between SS and PS were inverted as demonstrated in the present study. The results show that getting true physiological control data is not so simple but a complex task.