Treatment of spontaneous intracranial hypotension with epidural blood patch: is a complex approach necessary or better than a simple one?

Spontaneous intracranial hypotension (SIH) is a condition that has come to be recognized more frequently in recent years. The incidence is estimated at 2–5/100,000/year or about 50% of the incidence of subarachnoid hemorrhage. As it is a treatable condition, SIH has generated a great deal of interest in the last several years. The major symptom of SIH is orthostatic headache; however, the more serious problems relate to loss of buoyancy of the brain with ‘sagging’ toward the foramen magnum. These problems include subdural hematoma, cranial nerve palsies, and compression of the pons with obtundation, coma or focal brainstem signs. The condition usually results from leaks developing at the reflection of the pia mater to dura mater at the root exit zones in the cervical region or cervicothoracic junction. The leaks may also develop in the thoracic, lumbar and even sacral regions. Other sites of leaks may be the cribriform plate with rhinorrhea or the mastoid region with otorrhea, but these are less common. In most reports, a definite location of the leak is not established in a significant number of the cases. Nevertheless, the symptomatology can relate to the leak of cerebrospinal fluid from the subarachnoid space with subsequent brain sagging. For the leaks developing along the spinal column and for the leaks of undetermined origin, the epidural blood patch (EBP) has been the mainstay of treatment with a relatively high degree of success. The EBP appears to seal the leak by tamponade of the extradural space and promoting closure of the leak. It would appear that the major physiological change is to restore competence and volume to the subarachnoid compartment. The volume of blood employed for the EBP must be adequate to presumably provide the tamponade and seal. Usually, this will require more than 10 cc of blood and may require up to 40 cc. The usual volume limitations, increasing injection pain, should of course be adhered to. A second or even third blood patch may be required at times but should initiate a renewed pain analysis even if repeated blood patches are usually tolerated well. The success rates for EBP have ranged from around 33% to 90%. Schievink reported that one third of his patients responded well to single EBP, and he preferred to use two sites for delivery of the blood for the patch. The first blood patch would be done at the thoracolumbar region and the second in the lower lumbar region. Repeat patches could be done in 5 days. Berrior et al. presented a series of 30 subjects treated with blind lumbar EBP and noted that 27 had immediate relief, with 17 showing no relapse 1–4 years later. Nine subjects had repeat EBP of which six had sustained relief giving an overall good result for ‘blind’ EBP of 77%. Ferrante et al., in a more detailed report on 42 patients with SIH who underwent lumbar EBP, noted that 41 (97%) had immediate relief and 37 (88%) remained pain-free at follow-up 6–60 months later. Their approach involved placing the patient in a 30-degree Trendelenburg position for 1 h before and 24 h after the EBP along with pre-treatment with acetazola-