Hormonal shifts during pregnancy, especially the increase in relaxin and progesterone, along with weight gain, bring about significant changes in the musculoskeletal system. One of the most noticeable changes is the exaggeration of lumbar lordosis as the body adjusts to the growing fetus. This shift in posture causes the neck to flex forward, the shoulders to move downward, and the center of gravity to change. These adaptations help with balance but can also lead to back pain and discomfort. Additionally, in preparation for childbirth, joint laxity increases, particularly in the pelvis, allowing for greater flexibility during delivery.
These musculoskeletal changes can make anesthesia management more challenging, particularly when performing neuraxial techniques like epidurals and spinal anesthesia. The exaggerated lumbar lordosis reduces the space between the vertebrae, making it harder to properly flex the spine for needle placement. The widening of the pelvis, especially when the patient is in a lateral position, may lead to a head-down tilt, which can cause the local anesthetic to spread higher than intended. This can result in complications like low blood pressure or respiratory issues. To manage these risks, anesthesia providers can place a pillow under the dependent shoulder to counter the head-down tilt and better control the spread of the anesthetic, ensuring a safer and more effective administration.
