Dialysis Disequilibrium Syndrome and Intracranial Pressure Fluctuations in Neurosurgical Patients Undergoing Renal Replacement Therapy: Systematic Review and Pooled Analysis.

BACKGROUND: Dialysis disequilibrium syndrome is a rare, well-known, potentially life-threatening complication of renal replacement therapy (RRT), often involving cerebral edema and increased intracranial pressure (ICP). However, the impact of RRT on ICP and rate of dialysis disequilibrium syndrome in neurosurgical patients have not been systematically assessed. METHODS: In February 2022, a systematic review following PRISMA guidelines was conducted using various combinations of 9 keywords in the MEDLINE database. Eleven papers were selected. Individual patient data were extracted, pooled, and analyzed. RESULTS: Fifty-eight patients, 44 men and 14 women with a mean age of 48 years (6-78 years), were analyzed. Neurosurgical conditions included the following: spontaneous intracranial hemorrhage (n = 27), traumatic brain injury (n = 16), ischemic stroke/anoxic brain injury (n = 6), intracranial tumor (n = 6), and others (n = 3). Neurosurgical interventions included the following: craniotomy/craniectomy (n = 23), external ventricular drain or ICP monitor placement (n = 16), and burr hole or twist drill craniostomy (n = 4). Intermittent dialysis was used in 33 patients, continuous RRT in 20, and a combination thereof in 4. During RRT, ICP increased in 35 patients (60.3%), remained unchanged in 20, and decreased in 3. Thirty-four patients (65.4%) died. Intermittent dialysis was associated with increased ICP (73% vs. 37.5%, P = 0.01) and mortality (75% vs. 39.1%, P = 0.01). CONCLUSIONS: In neurosurgical patients, ICP increases during RRT are common, affecting up to 60%, and potentially life-threatening, with mortality rates as high as 65%. The use of a continuous rather than intermittent RRT technique may reduce the risk of this complication. Prospective studies are warranted.

Through-and-through stab wound of the cervical spinal canal with retained weapon but no neurological repercussions: an exceptionally rare injury and the case for direct withdrawal. Illustrative case.

BACKGROUND: Nonmissile penetrating spinal injuries are rare and potentially debilitating. Such injuries can sometimes be complicated by the retention of a foreign body, which is usually part of the assailant's weapon, making their management even more problematic. OBSERVATIONS: We present a unique case of stab wound to the neck with a retained ice pick, traversing the spinal canal from one intervertebral foramen to the other, yet with no ensuing neurological damage to the patient. After carefully analyzing the weapon's trajectory on computed tomography and ruling out vertebral artery injury via catheter angiography, the ice pick was successfully withdrawn under general anesthesia and intraoperative neurophysiological monitoring, averting the need for a more invasive surgical procedure. LESSONS: Stab wounds of the spinal canal with a retained foreign body can occasionally be managed by direct withdrawal. Whether this simple technique is a safe alternative to open surgical exploration should be determined on a case-by-case basis after careful review of spinal and vascular imaging. The absence of significant neurological or vascular injury is an absolute prerequisite for attempting direct withdrawal. Moreover, preparations should be made for possible conversion to open surgical exploration in the rare event of active hemorrhage, expanding hematoma, or acute neurological deterioration.

Sinking bullet syndrome: A unique case of transhemispheric migration.

BACKGROUND: Spontaneous migration of retained intracranial bullet fragments is an increasingly recognized phenomenon. However, such migration is usually limited in extent, since it occurs along the bullet tract or cerebrospinal fluid (CSF) spaces. Transhemispheric migration through an intact cerebral hemisphere has not been previously reported. OBSERVATIONS: A 20-year old man sustained a gunshot wound (GSW) to the head with a left parieto-occipital entry point, resulting in retained bullet fragments within the anterior right frontal lobe. The patient developed medically refractory intracranial hypertension, necessitating a left decompressive hemicraniectomy. He exhibited a favorable postoperative course, with gradual neurologic recovery, and was ultimately discharged to a rehabilitation facility. Notwithstanding, serial head CT scans during the first 2 weeks revealed gradual transhemispheric migration of bullet fragments from the right frontal pole to the right occipital pole, traveling through largely intact, uninjured brain tissue. LESSONS: Transhemispheric migration of bullet fragments via intact brain tissue may rarely occur. While the exact mechanisms underlying this phenomenon remain unclear, potential factors may include: bullet weight, CSF pulsations, dissection through white matter tracts, and biomechanical effects of large skull defects. Bullet migration does not necessarily delay or prevent neurologic recovery.