Lithotomy Position
The lithotomy position is used frequently in gynecologic and urologic
surgery. The simultaneous elevation of the legs while the person is in the supine
position provides the advantages of reducing torsion on the pelvis and lower back.
Translocation of the vascular volume is promoted centrally. However, the areas
that support the weight of the legs provide points of potential nerve and muscle
injury (see Fig. 28-2
).
The goal is to suspend or support the legs so that they are flexed at the hips perpendicular
to the torso and spread far enough apart to allow appropriate access to the perineum
and abdomen. Sometimes, less flexion of the hips is required. There are several
devices to support the legs, with vertical bars common to all of them. The support
from the bars may be by built-in concave metal supports or by straps ( Fig.
28-2
and Fig. 28-4
).
Both of these positions usually require additional padding.
There is risk of injury to the peroneal nerve if it is compressed
between the head of the fibula and the bar or the support structures. Pressure over
the medial tibial condyle may result in saphenous nerve injury (see Fig.
28-2
). More common nerve injuries associated with the lithotomy position
are discussed in "Lower Extremity Neuropathies."
Figure 28-4
Lithotomy position with less hip flexion for endoscopic
procedures such as transurethral resection of the prostate. (Adapted Martin
JT. Lithotomy positions. In Martin JT, Warner MA
[eds]: Positioning in Anesthesia and Surgery, 3rd ed. Philadelphia, WB Saunders,
1997, p 50.)
Lower extremity compartment syndrome is a recognized complication
of the lithotomy position. A review of 572,498 surgical procedures done between
1989 and 1999 at the Mayo Clinic found 13 cases of compartment syndrome requiring
fasciotomy.[28]
The complication was not limited
to the lithotomy position (1 per 8720), occurring almost as frequently in the lateral
position (1 per 9711) and in some supine patients (1 per 92,441). Surgical procedures
in which compartment syndromes developed were longer (7.2 hours) on average than
the mean length of procedures for all patents (2.7 hours) during the study period.
A devastating injury in this position, which is fortunately uncommon,
is hand and finger injury. As the foot of the bed is being rolled to a vertical
position, care must be taken that the fingers are not caught in the gap and
Figure 28-5
Lithotomy position with straps instead of stirrups for
leg support. Inset shows the risk to the fingers
when the lower portion of the operating table is lowered. (Adapted from
Martin JT: Lithotomy positions. In Martin JT, Warner
MA [eds]: Positioning in Anesthesia and Surgery, 3rd ed. Philadelphia, WB Saunders,
1997, p 67.)
crushed ( Fig. 28-5
). Compartment
syndrome of the hand can occur if it is compressed between the buttocks and the operating
table. In the lithotomy position, pooling of the preparation solution under the
buttocks and lower back can result in a chemical burn; it is wise to remove all drapes
in this area after preparation so that puddles of residual solution can be removed.
