Cardio-Vascular Events at Defecation: Are They Unavoidable
G. A. SIKIROV
Abstract – Cardio-vascular events at defecation are to a considerable degree the consequence of an unnatural (for a human being) seating defecation posture on a common toilet bowl or bed pan. The excessive straining expressed in intensively repeated Valsalva Maneuvers is needed for emptying the bowels in sitting position. The Valsalva Maneuver adversely affecting the cardio-vascular system is the causative factor of defecation syncope and death. The cardiovascular system of a healthy man withstands the intensive and repeated straining at defecation, while the compromised cardio-vascular system may fail resulting in syncope or even death. The squatting defecation posture is associated with reduced amounts of straining and may prevent many of these tragic cases.
Introduction and Discussion
Cardio-vascular events during straining at defecation are not rare. The reports of bed pan deaths, defecation syncope and cardiac rhythm disturbances are described repeatedly. Probably every physician practicing emergency medicine has encountered tragic cases of sudden death in the lavatory. Patients with acute coronary events are especially vulnerable to excessive straining which accompany defecation. Therefore it is a routine practice in coronary care units to administer laxatives or stool softeners, hopefully to reduce straining at defecation. The defecation act results from the coordination efforts of both voluntary and reflex muscle activity. As a consequence of voluntary straining, while the glottis is closed the abdominal and intrathoracic pressures rise, a chain of events known as Valsalva Maneuver. The Valsalva Maneuver under controlled conditions is considered to be a safe procedure and used as a diagnostic and therapeutic tool. However, the Valsalva Maneuver at defecation on a common toilet bowl or bed pan is much more intensive, repeated closely and protracted. Thus, large swings in the level of arterial pressure and heart rate during straining at defecation. In some cases, blood pressure reached an alarming level. It was found that the Valsalva Maneuver induces a sharp rise of intravenous and intra-arterial pressure and reduction of coronary flow velocity and cerebral blood flow. Bradycardia, high grade A-V block, ectopic rhythm of nodal type and other types of cardiac rhythm disturbances were found in the persons performing Valsalva Maneuver.
Conclusion
There is usually common agreement that the ideal defecation posture for a human being is squatting. However, until recently the medical world has not realized the dimensions of the damage to health that may be caused by the sitting defecation posture. Both cardio-vascular and gastro-intestinal systems may undergo injury.
Additional research on the subject is necessary.