Pudendal Nerve block for anorectal and genitals surgeries скачать в хорошем качестве

Pudendal Nerve block for anorectal and genitals surgeries

Pudendal anesthesia, also known as a pudendal block, or saddle block, is a form of local anesthesia commonly used in the practice of obstetrics to relieve pain during the delivery of baby by forceps. The pudendal nerve block prevents fainting during forceps delivery which was common before pudendal nerve block use was available. The anesthesia is produced by blocking the pudendal nerves near the ischial spine of the pelvis.[1][2] The ischial spine separates the greater and lesser sciatic foramina at the exit of the bony pelvis.[citation needed] The pudendal block gets its name because a local anesthetic, such as lidocaine or chloroprocaine, is injected into the pudendal canal where the pudendal nerve is located. This allows quick pain relief to the perineum, vulva, and vagina. A pudendal block is usually given in the second stage of labor just before delivery of the baby. It relieves pain around the vagina and rectum as the baby comes down the birth canal. It is also helpful just before an episiotomy. Lidocaine is usually preferred for a pudendal block because it has a longer duration than chloroprocaine which usually lasts less than one hour.[3] Pudendal nerve block is useful in evaluating patients with perineal somatosensory pain. B. Anatomy The pudendal nerve arises from S2–S4 and courses between the sacrospinous and the sacrotuberous ligaments to reach the perineum. C. Technique This block is usually performed transperineally with the patient in the lithotomy position ( Figure 47–19) although it may be performed via a posteriorapproach in the prone position. Injection of anes-thetic is carried out percutaneously just posterior to the ischial spine at the attachment of the sacro-spinous ligament. The ischial spine can be palpated transrectally or transvaginally. Alternatively, this procedure may be performed in the prone position with a 22-gauge needle directed toward the base of the ischial spine. Patients should be advised that they may have numbness of the genitalia for hours after this procedure is performed. D. Complications Potential complications include unintentional sci-atic blockade and intravascular injection.