A nurse discourages a patient from straining excessively when attempting to have a bowel movement. What physiological response primarily may be prevented by avoiding straining on defecation?

Correct Answer: B. Dysrhythmias

Straining on defecation requires the person to hold the breath while bearing down. This maneuver increases the intrathoracic and intracranial pressures, which can precipitate dysrhythmias, brain attack, and respiratory difficulties; all of these can be life threatening. Strain at stool causes blood pressure rise, which can trigger cardiovascular events such as congestive heart failure, arrhythmia, acute coronary disease, and aortic dissection.

• Option A: The loss of the voluntary ability to control the passage of fecal or gaseous discharges through the anus is caused by impaired functioning of the anal sphincter or its nerve supply, not straining on defecation. Fecal incontinence is the inability to control bowel movements, causing stool (feces) to leak unexpectedly from the rectum. Also called bowel incontinence, fecal incontinence ranges from an occasional leakage of stool while passing gas to a complete loss of bowel control.
• Option C: Fecal impaction is caused by prolonged retention and the accumulation of fecal material in the large intestine, not straining on defecation. Fecal impaction is a severe bowel condition in which a hard, dry mass of stool becomes stuck in the colon or rectum. This immobile mass will block the passage and cause a buildup of waste, which a person will be unable to pass.
• Option D: Although straining on defecation can contribute to the formation of hemorrhoids, this is not the primary reason straining on defecation is discouraged. Hemorrhoids, although painful, are not life-threatening. Hemorrhoids are rich in vascular supply and have a tendency to engorge and prolapse. Symptoms can vary from mild itching, bleeding to severe pain. Unfortunately, because of the location, many patients never seek treatment for fear of embarrassment.