Sinus bradycardia is defined as a HR
Under 60 BPM
Heart rate is increased by approximately 10 BPM for every _____ increase in *F of body temperature.
Explain SNS mediated tachycardia.
Due to blood loss or other shock states, the SNS attempts to maintain perfusion/B.P. by releasing catecholamines, which produce tachycardia
Explain the almost constant stroke volume in endogenously mediated sinus tachycardia.
Due to catecholamines, contractility is increased; skeletal muscle pump also increases venous return to the heart
Explain the decreased cardiac output in pathologically induced tachycardia.
Decreased blood volume; lack of skeletal muscle pump decreases preload (often, ill people aren't moving around)
Explain physiology of respiratory induced sinus arrhythmia.
The respiratory control centers in the medulla lie next to the cardiac vasomotor centers. With deep inspiration, there is "spillover," which changes heart rate.
Sinus tachycardia is defined as a heart rate greater than _____
2*, Type I
Progressive PRI until dropped beat
2* Type II
Multiple dropped beats
Complete dissociation of SA/AV
Regular P-P interval
Regular R-R interval
No 1:1 P:QRS