This patient position is necessary to perform examinations or carry out operations in the branches of urology, gynecology, or proctology.
The lithotomy position is also used as a common position for childbirth.
The term lithotomy refers to the historical techniques used in bladder stone therapy since, in the past, these were the perineal access routes to the stones in the gallbladder.
The standard lithotomy position requires patients’ legs to be separated from the midline at 30 to 45 degrees of abduction, with the hips flexed until the thighs are at an angle of 80 to 100 degrees.
The patient’s legs are placed in stirrups, with the knees bent so that the lower legs are parallel to the plane of the torso.
The lithotomy position is used for various open and endoscopic urologic procedures.
Surgery of the membranous urethra or perineal access to the prostate requires an extreme lithotomy position.
With additional flexion of the lumbar spine, lifting of the buttocks, with the help of an oblique positioning cushion, and increased flexion of the hip joint, the perineum can be aligned parallel to the floor.
The legs must be mounted on special supports. Filling all relevant pressure points is of utmost importance.
Lithotomy position procedures
- Prostate examination.
- Transurethral resection of the bladder.
- Transurethral resection of the prostate.
- Surgery of the female urethra: tension-free vaginal tape, treatment of the urethral caruncle.
- Male urethral surgery: internal urethrotomy.
- Perineal prostatectomy.
- Gynecological exams.
- Endoscopic procedures, among others.
Lithotomy positions are commonly used for urologic, gynecologic, and colorectal surgical procedures.
Lithotomy positions can be described as low, standard, high, and exaggerated.
These different lithotomy positions differ mainly by the degree of hip angulation and the height of the leg placement.
Because the hydrostatic arterial pressure gradient between the ankle and the heart in these positions can lower blood pressure in the lower extremities and contribute to hypoperfusion of the lower extremities in patients who undergo procedures in these lithotomy positions.
Contraindications to a lithotomy position
To avoid positioning and handling the lower extremities (e.g., tight compression wraps on elevated legs).
These can affect blood flow, especially in procedures where patients spend prolonged periods in lithotomy positions.
Contractures or diseases of the hip joint may prevent a lithotomy position, mainly if flexion or abduction of the hip joint is not possible.
Obstetricians have widely used the lithotomy position to allow easier access to the mother. However, this position is not based on evidence.
It carries many adverse effects, including narrowing the pelvic outlet, pressure on the coccyx, restricting the mother’s movement, excessive tension on the perineum, and increased risk of tearing.
Increased discomfort of patients, lengthening of the pushing stage, increases the risk of fetal malpresentation and causes the mother to push uphill with labor against gravity.
In addition to neurologic complications, other complications that have been reported after procedures in the lithotomy position include lower extremity compartment syndrome, venous thrombosis, and rhabdomyolysis.
The most common neuropathies of the lower extremities associated with procedures in the lithotomy position can affect the common perineum, femoral, and sciatic nerves.
Other nerves that suffer minor damage include the obturator and femoral cutaneous nerves.
Placing the mother in this position during labor can compress major blood vessels, including the vena cava, limiting blood flow to the baby and putting him at greater risk.
Lower blood flow rates cause more mothers and babies to die unnecessarily during childbirth.
Despite solid evidence that there are no benefits to this position and that it only causes complications, often leading to interventions that might otherwise have been avoided, clinicians persist in using this weak position to carry out the delivery of a baby.
Careful patient positioning is key to avoiding injury. Well, padded stirrups are necessary; the patient’s heel should be placed firmly on the stirrup foot so that the patient’s heel supports the weight of the leg.
It is also helpful to tilt the stapes back to avoid applying pressure to the posterior and lateral aspects of the lower limb, which will help prevent common peroneal nerve injury. This area can be further filled in if necessary.
To avoid brachial plexus injury, the patient’s arms should rest easily and should not be extended more than 90 °. Also, nothing should be placed between the shoulder blades that can stretch the brachial plexus by elevating the chest.
The anesthesiologist and operating personnel should also monitor the position of the arms because they can change during the procedure, especially if the patient is placed in the Trendelenburg position for additional exposure.
Finally, great care must be taken when using a self-retaining retractor to prevent femoral injury. Retractors over the groin should be used with caution, especially in lean patients.
However, if necessary, the most superficial retractor available such as the bladder, should be used because the deeper retractors are more likely to compress the femoral nerve, which runs just below the psoas muscle.
If the operation is prolonged periodically, the retractors should be released and replaced to limit the potential for protracted compression to an isolated location.
If a perineal approach is necessary at any time, be careful to remove the retractors from the abdominal wall.