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J A Purcell

Publications and source records attributed to J A Purcell.

10 recordsLinked to original sources
PubMed1990

Advances in the treatment of dilated cardiomyopathy.

The nursing care of the patient with dilated cardiomyopathy focuses on (1) improving right and left heart function, i.e., titrating vasoactive drugs to maintain acceptable cardiac index with minimum side effects (and/or monitoring the operation of a left ventricular assist device when left heart function is refractory to vasoactive drugs), (2) reducing cardiac filling pressures with diuretics, vasodilators, and/or restriction of dietary sodium, oral and IV fluids, (3) maintaining optimum oxygenation, (4) preventing complications associated with either the disease or treatment, and (5) assisting the patient/family to maintain hope during the often lengthy and crisis-filled wait for a donor heart. The critical care nurse is challenged, often for weeks or months at a time, by the complexity of this patient's physical and emotional needs and functions in a collaborative role with the entire health team in an attempt to maintain both cardiovascular and psychological stability until a donor heart is available.

Cardiomyopathy, Dilated↗
PubMed1989

Cardiomyopathy.

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Arrhythmias, Cardiac↗
PubMed1985

A pacemaker primer.

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Arrhythmias, Cardiac↗
PubMedDate not supplied

Provoking vasodepressor syncope with head-up tilt-table testing.

Head-up tilt testing has proven effective in identifying individuals prone to vasodepressor syncope (VDS). VDS refers to the transient loss of consciousness/cerebral anoxia seen with hypotension produced by autonomic imbalance. In this case, the hypotension is the result of parasympathetic domination. Most episodes appear to be triggered by reduced venous return which stimulates the cardiac mechanoreceptors in the inferior-posterior left ventricle. Once activated, these receptors send out afferent signals along the unmyelinated C of the vagus nerve and cause vasodilation. Once venous return is restored, the usual sympathetic compensations (increased heart rate/force of contraction and vasoconstriction) overcome the parasympathetic domination. A tilt-study allows one to passively tilt the patient up to 40-80 degrees and abruptly reduce venous return in a controlled environment. One can then determine which mechanism will dominate--the usual sympathetic vasoconstriction or the parasympathetic reflex (Bezold-Jarisch)--by frequent observations of blood pressure and ECG. Bradycardia/ventricular standstill may also occur during parasympathetic domination. Once susceptibility to vasodepressor syncope is identified by a tilt study, medications to expand the blood volume and/or minimize venous pooling are often needed. Other drugs to block the parasympathetic pathway and/or the effects of excessive catecholamine levels may also be ordered. Dual chamber pacing may be required for malignant episodes of bradycardia or ventricular standstill.

Electrocardiography↗