Newton’s third law of motion is: For every action, there is an equal and opposite reaction. Where do vacuum-producing medical devices fit into Newton’s description of the physical world? How are vacuum applications for erectile dysfunction and wound management similar?
“Vacuum” is quite simply defined as a space that is partially exhausted by artificial means, such as with an air pump. Evacuating air from a cylinder, or other confined areas, using a vacuum pump creates a pressure differential. As more air is removed from a cylinder using a pumping mechanism, the potential vacuum force becomes greater. There are several units of measurement to quantify this pressure differential, but the height of a column of mercury in inches is a commonly-used standard measurement for the force of a vacuum.
In the spirit of Newtonian physics, when a penis pump creates below-normal atmospheric conditions and a vacuum is created in a cylinder, this must be answered with an equal and opposite reaction. As atmospheric pressure is removed from the cylinder via a pumping mechanism and a vacuum is created, an equal amount of force is created, requiring an equal amount of some substance to be pulled into the cylinder.
In the case of a penis pump, the opposite reaction to the force of a created vacuum is achieved with the pull of blood from the body into the flaccid penis which rests in a vacuum cylinder or chamber. FDA design features for penile rigidity devices calculate that 16.5 to 17 inches of mercury per inch is the maximum amount of vacuum-created pressure necessary to achieve a full erection.
Blood flow is the therapeutic medical treatment produced by a vacuum device or penis pump. Specifically, oxygen-rich arterial blood flow is pulled into flaccid penile tissues. Blood flow is what results from creating a vacuum with a penis pump in a manner consistent with Newton’s third law of motion.
The therapeutic benefits of oxygen-rich blood flow to penile tissues and the prevention of the loss of penile length, are the focus of many clinical studies and thought leaders in the field of urology. Of course, we know that blood creates erections, but there is more: Oxygen-rich blood flow keeps virtually all of the tissues and cells in our body healthy.
It is estimated that in 2018 alone, 164,490 men will be diagnosed with prostate cancer. Most prostate cancer treatments will either permanently or temporarily render a man’s body incapable of creating erections. As a result, surgeons and scientists have focused on prevention and treatment of erectile dysfunction. The buzzword used by urologists and ED specialists is penile rehabilitation. Penile rehabilitation is a means of using medical interventions to create erections that use blood flow to oxygenate tissues and maintain or create penile health.
The aim of erections that bring oxygen-rich blow flow to flaccid penile tissues is to prevent penile shrinkage, programmed cell death, and penile atrophy until severed nerves heal. Penile rehabilitation following a radical prostatectomy is done with the hope of restoring natural function. The depravation of oxygen in these tissues resulting from the absence of erectile function is defined in medical literature as hypoxia.
What is a wound vac? Vacuum-assisted closure of a wound is a type of therapy that helps wounds heal. A wound vacuum device removes pressure over the area of the wound. Basic studies have shown beneficial effects on wound blood flow and proliferation of healing granulation tissue using a vacuum pump for wound healing.
There are many benefits of negative pressure therapy. By creating a controlled negative pressure condition, this type of wound therapy can:
- Accelerate wound healing times;
- Reduce the risk of pathogenic infection;
- Reduce the number of dressing changes; and
- Increase blood flow to the wound area while simultaneously drawing out excess fluids.
A clinical study published in the Annals of Thoracic Surgery concluded that “Vacuum-assisted closure therapy induces a change in microvascular blood flow that is dependent on the pressure applied.” Wound fluid, partial pressure of oxygen and lactate levels increase during vacuum-assisted closure therapy. This combination is known to promote wound healing.
A clinical study published in Reviews of Urology determined the following to be among the main points of the clinical study. “A majority of patients have arterial insufficiency and venous leakage following RP, which is associated with arterial insufficiency. This causes hypoxia and subsequently increased production of transforming growth factor-b, apoptosis, and collagen deposition, culminating in corporeal fibrosis. The concept behind penile rehabilitation is the recovery of erectile function following RP by prevention and reversal of some of the aforementioned changes. There is convincing evidence that vacuum erection devices are successful in the treatment of ED following Radical Prostatectomy.”
We don’t usually consider wound management and the treatment of erectile dysfunction as similar. However, when treatments for these seemingly unrelated conditions utilize a vacuum or negative pressure, some common themes emerge. When vacuum devices induce oxygen-rich blood to tissues that are deprived of oxygen (when hypoxia occurs), damaged by trauma, or require healing, there seems to be an apparent therapeutic benefit in the form of vacuum-assisted movement of blood to these tissues.