Priapism describes a prolonged erection lasting at least four hours, occurring without sexual stimulation or after it has ended. This condition is a medical emergency. Immediate medical attention is necessary to prevent irreversible damage to penile tissues.
Understanding Priapism Types
Priapism is categorized into two types: ischemic and non-ischemic. Ischemic priapism, also known as low-flow priapism, is the more common type, accounting for over 95% of cases. It occurs when blood becomes trapped within the penis, preventing fresh, oxygenated blood from circulating. This lack of blood flow requires urgent intervention.
Non-ischemic priapism, or high-flow priapism, is less common and usually results from an injury to the penis or surrounding area. This type involves unregulated arterial blood flow into the penis, often due to a fistula or pseudoaneurysm. Unlike ischemic priapism, the blood in non-ischemic cases remains oxygenated, making it less immediately damaging to tissues.
The Progression of Untreated Ischemic Priapism
When ischemic priapism goes untreated, damaging physiological events occur within penile tissues. The trapped blood quickly becomes deprived of oxygen, leading to tissue hypoxia. As oxygen levels drop, metabolic waste products build up, causing the tissue to become acidic, a condition known as acidosis. This acidic, oxygen-poor environment compromises the health of the smooth muscle cells within the penis.
Prolonged hypoxia and acidosis cause cellular damage and, eventually, cell death (necrosis) within the erectile tissue. Microscopic tissue damage can begin as early as six hours, with permanent structural changes developing after about 12 hours. As the duration extends beyond 24 hours, significant cellular damage and the formation of scar tissue (fibrosis) become more likely. This process can lead to the penis becoming rigid.
Visually, the penis may initially appear bruised, then progressively change color, becoming bluish or even black as tissue necrosis advances. This discoloration indicates severe lack of blood flow and dying tissue. The glans penis (tip) remains soft, while the shaft is rigid and often tender. Extensive scar tissue permanently impairs the penis’s ability to achieve or maintain an erection, resulting in irreversible erectile dysfunction. If priapism lasts longer than 24 hours, the risk of permanent erectile dysfunction is very high.
The Necessity of Immediate Treatment
Immediate medical intervention is the only way to prevent the irreversible damage caused by untreated ischemic priapism. Seeking emergency medical care within the first few hours is important for preserving erectile function. Delaying treatment significantly increases the likelihood of permanent tissue damage and erectile dysfunction.
Emergency treatment aims to drain the stagnant blood from the penis and restore normal blood circulation. A common procedure involves corporal aspiration, where a healthcare provider uses a needle to draw out the trapped, deoxygenated blood from the penis. This may be followed by or combined with the injection of sympathomimetic drugs, such as phenylephrine, directly into the penis. These medications help to constrict blood vessels, allowing the trapped blood to drain and fresh blood to flow in, thereby alleviating the erection.