Which of the following structures is the primary pacemaker of the heart?
a. Ventricular tissue c. Sinoatrial node
b. Atrioventricular node d. Purkinje fibers
C
With an intrinsic rate of 60 to 100 beats/min, the sinoatrial node is the primary pacemaker in a healthy heart. The atrioventricular node beats 40 to 60 beats/min. Ventricular tissue must have an electrical impulse to contract. Purkinje fibers beat 15 to 40 beats/min.
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The nurse is monitoring the client's ability to tolerate the tube feeding through a new g-tube. The client's gastric residual is currently 315 milliliters
Which of the following nursing interventions should be performed at this time? (Select all that apply.) 1. Increase the head-of-bed to a 45-degree angle 2. Change tube feeding setup 3. Hold tube feeding formula 4. Add blue food dye to formula 5. Consider bolus tube feeding
The nurse is assessing a client's muscle tremors associated with Parkinson's disease. Which clinical finding does the nurse anticipate?
A. Fasciculations. B. Athetoid movements. C. Chorea. D. Rhythmic shaking.
Which of the following symptoms is a known side effect of antibiotics?
A) Diarrhea B) Constipation C) Fecal impaction D) Abdominal bloating
Pyridostigmine is useful in treating patients with myasthenia gravis because:
A. it causes the reversible inhibition of acetylcholinesterase, thereby increasing the levels of acetylcholine at the skeletal neuromuscular junction. B. it causes the irreversible inhibition of acetylcholinesterase, thereby increasing the levels of acetylcholine at the parasympathetic postganglionic nerve endings. C. it increases the secretion of acetylcholine from cholinergic nerve endings. D. it binds to nicotinic-muscle receptors and produces the same effects as those of acetylcholine.