Strait catheter. Unfortunately, this complication is all too common in men, it does resolve but may take several hours. As one recovers from a spinal/epidural, the sacral nerve roots are among the last to recover. Autonomic innervation governs urine extrusion-the urinary sphincter dilating and bladder contracting. This reflex is transiently impaired in some. Catheterization may be performed if bladder overfill.