Cardiovascular effects of lithotomy positioning are also similar to those in the supine position. However, with leg elevation, there is a transient rise in cardiac output secondary to an increased return of in venous blood from the legs augmenting preload. Nearly all types of anesthesia can be provided with the patient in the lithotomy position.
Patient body habitus and exact leg height must be determined prior to the procedure when contemplating MAC or the use of LMA. The physiologic changes as well as the comfort of the patient might make these techniques unsuitable or unsafe. Peripheral nerve injury has been reported after surgery in the lithotomy position. Injury to the common peroneal nerve appears to be the most common nerve injured.
Symptoms include motor weakness in ankle extension, ankle eversion, and foot dorsiflexion. This can be accompanied by variable sensory loss of the dorsal foot and lateral leg. The mechanism of injury appears to be related to stretch and compression of the peroneal nerve. Overall, the risk of peroneal nerve injury increases with the length of surgery. Reports indicate a fold increase in injury risk per hour spent in the lithotomy position.
This can be minimized by intraoperative position changes of the legs to limit the time spent in lithotomy. Recent evidence suggests a decreasing incidence of common peroneal nerve injury due to better awareness and proper surgical positioning.
Other potential nerve injuries include compression of the lateral femoral cutaneous nerve leading to lateral thigh pain or meralgia paresthetica. The femoral nerve can be injured via compression beneath the inguinal ligament with extreme thigh abduction and external rotation of the hip.
Femoral nerve injury leads to quadriceps muscle weakness, loss of knee jerk reflex, and sensory loss over the thigh and medial leg.
Sciatic nerve injury has been reported after lithotomy with excessive hip flexion. Compartment syndrome is another potential serious complication related to the lithotomy position.
The exact mechanism is not completely understood. Overall, arterial pressure of the lower extremity decreases proportionately with the height of leg raise in the lithotomy position. Also, lower extremity compartment pressures increase predictability for unknown reasons when placed in the lithotomy position. The combination of a lower arterial pressure and elevated compartment pressure potentially lead to ischemia of the lower extremity musculature and soft tissue.
Of all standard surgical positions, lithotomy, followed by the lateral decubitus position, puts the patient at the greatest risk for compartment syndrome. Length of time spent in the lithotomy position is the only established evidence-based risk factor and 2 hours appears to be the point at which this risk substantially increases.
Other potential risk factors include obesity, blood loss, vascular disease, and intraoperative hypotension. Intermittent pneumatic compression devices used to increase lower extremity circulation have not been implicated in the development of compartment syndrome in the lithotomy position. A more detailed discussion of arm position can be found in the chapter on the supine position.
When the foot section of the operating room table is brought back to the normal position at the conclusion of the procedure, the table can impinge the hand or fingers leading to serious crush injury. Careful attention must be paid to the hands prior to raising the foot of the table.
As previously stated, the lithotomy position is associated with several lower extremity nerve injuries, including the common peroneal, lateral femoral cutaneous, femoral, and sciatic nerves. In the lithotomy position, the legs are positioned into maneuverable supports, allowing the surgeon the freedom to move either leg in nearly all planes of motion.
Specific care must be paid to the position of the knee. Proper positioning does not allow external compression or fixation of the lateral leg at the fibular head to avoid pressure on the peroneal nerve. The risk of nerve injury increases with every hour spent in the lithotomy position. Intraoperative position changes of the legs can minimize the time spent in lithotomy and potentially limit nerve injuries.
To limit the risk of injury to the lateral femoral cutaneous, femoral, and sciatic nerves, excess hip flexion and abduction should be avoided. Another complication of the lithotomy position is lower extremity compartment syndrome. These data suggest that lower-extremity systolic pressures may be reduced significantly in some patients and that the lower extremities may be at risk for ischemia.
Prolonged ischemia during surgical procedures performed on patients in lithotomy positions probably increases the risk of compartment syndrome. Therefore, our findings suggest that duration of time in the lithotomy position should be minimized when the lithotomy position is necessary for only a portion of a lengthy procedure.
Careful planning may allow the remainder of the procedure to take place before establishing the lithotomy position or the position to be changed to an alternative when it is no longer needed. Sign In or Create an Account. Advanced Search. Sign In. Skip Nav Destination Article Navigation. Close mobile search navigation Article navigation. Volume 89, Issue 6. Previous Article Next Article.
Article Navigation. Clinical Science December Halliwill, PhD ; John R. Halliwill, PhD. This Site. Google Scholar. Scott A. Hewitt, BS ; Scott A. Hewitt, BS. Michael J. Joyner, MD ; Michael J. Joyner, MD. Mark A. Warner, MD Mark A. Warner, MD. Author and Article Information. Hewitt Graduate Student, Department of Anesthesiology. Warner Professor, Department of Anesthesiology. Anesthesiology December , Vol. Get Permissions. View large Download slide. Table 1. Group Means for Systolic Pressure.
View large. View Large. Surgery ; This same study, as well as another from , found that a squatting position was less painful and more effective during the second stage of labor. Having to push the baby up works against gravity. In a squatting position, gravity and the weight of the baby help open the cervix and facilitate delivery. In addition to making it harder to push during labor, the lithotomy position is also associated with some complications.
One study found that the lithotomy position increased the likelihood of needing an episiotomy. This involves cutting the tissue between the vagina and anus, also called the perineum, making it easier for the baby to pass through. A study similarly found a higher risk of perineal tears in the lithotomy position. Another study linked the lithotomy position with an increased risk of injury to the perineum when compared with squatting lying on your side.
Another study comparing the lithotomy position to squatting positions found that women who gave birth in the lithotomy position were more likely to need a Caesarian section or forceps to remove their baby.
Sphincter injuries can have lasting effects, including:. Keep in mind that giving birth is a complex process with many potential complications , regardless of the position used. As you go through your pregnancy, talk to your doctor about possible birthing positions. They can help you come up with options that balance your personal preferences with safety precautions. In addition to childbirth, the lithotomy position is also used for many urological and gynecological surgeries, including:.
Similar to using the lithotomy position for childbirth, undergoing surgery in the lithotomy position also carries some risks. The two main complications of using the lithotomy position in surgery are acute compartment syndrome ACS and nerve injury. ACS happens when pressure increases within a specific area of your body.
This increase in pressure disrupts blood flow, which can hurt the function of your surrounding tissues. The lithotomy position increases your risk of ACS because it requires your legs to be raised above your heart for long periods of time.
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