Local cooling for traumatic spinal cord injury: outcomes in 20 patients and review of the literature

Abstract

<jats:sec> <jats:title>Object</jats:title> <jats:p>In this prospective study, the authors offered protocol-selected patients a combination of parenteral steroids, decompression surgery, and localized cooling to preserve viable spinal cord tissue and enhance functional recovery.</jats:p></jats:sec> <jats:sec> <jats:title>Methods</jats:title> <jats:p>After acquiring informed consent, the authors offered this regimen with localized deep cord cooling (dural temperature 6°C) to 20 patients with a neurologically complete spinal cord injury to begin within 8 hours of injury. After decompression, the cord was locally cooled through the intact dura using a suspended extradural saddle at the site of injury for up to 4 hours, during which time spinal fusion was performed. Sensation and motor function were evaluated directly after the injury and again over a year later. The patients were evaluated using the 2011 amendment to the American Spinal Injury Association (ASIA) Impairment Scale.</jats:p></jats:sec> <jats:sec> <jats:title>Results</jats:title> <jats:p>Eighty percent of the 20 patients (12 with cervical and 4 thoracic injuries) with an initial neurologically complete cord injury had some recovery of sensory or motor function. All patients initially had ASIA Grade A impairment. Of 14 patients with quadriplegia, 5 remained ASIA Grade A, 5 improved to ASIA Grade B, 3 to ASIA Grade C, and 1 to ASIA Grade D. The remaining 6 patients had suffered a thoracic spinal cord injury, and of these 2 remained ASIA Grade A, 1 recovered to ASIA Grade B, 2 to ASIA Grade C, and 1 ASIA Grade D. All considered, of 20 patients, 35% remained ASIA Grade A, 30% improved to ASIA Grade B, and 25% to ASIA Grade C. Impairment in 2 (10%) of 20 patients improved to ASIA Grade D. The mean improvement in neurological level of injury in all patients was 1.05, the mean improvement in motor level was 1.7, and the mean improvement in sensory level was 2.8. Two patients recovered the ability to walk, 2 could extend their legs, 5 could sense bladder fullness, and 3 had partial ability to void voluntarily. Four males recovered subnormal ability to have voluntary erection sufficient for limited sexual activity.</jats:p></jats:sec> <jats:sec> <jats:title>Conclusions</jats:title> <jats:p>The authors present here results of 20 patients with neurologically complete spinal cord injury treated with a combination of surgical decompression, glucocorticoid administration, and regional hypothermia. These patients experienced a better recovery than might have been expected had traditional forms of treatment been used. The benefit of steroid treatment for cord injury has been debated in the last decade, but the authors feel that research into the effects of cord cooling should be expanded. Given that the optimal neuroprotective temperature after acute trauma has not yet been defined, and may well be below that which is considered safely approachable through systemic cooling, methods that allow for the early attainment of such a temperature locally should be further explored. The results are encouraging enough to suggest the undertaking of controlled clinical trials of treatment using localized spinal cord cooling, where such treatment can be instituted within hours following injury.</jats:p></jats:sec>

Clinical therapeutic guideline for neurorestoration in spinal cord injury (Chinese version 2016)

“…Understanding these variables can maximize the safety of injections and avoid injury to spared structure. 23 …”

“…Local hypothermia treatment can decrease the metabolism of the injury site, reducing oxygen consumption, which could be performed in an open or a closed environment through an epidural or subdural coolant lavage (6°C) 23 or an intravascular route (at 34°C). 24 …”

Letters to the Editor: Hypothermia for spinal cord injury

“…7 Local spinal cord cooling was more popular in 1970s and early 1980s when several groups had used local cooling in humans and animals with variable but generally good results. 3,4,8,10,11,16,18,20,21 The potential benefits of providing hypothermia directly to the injured region obviated many of the risks of deep systemic hypothermia and resulted in many studies in large animals, leading to application in humans. Local cooling trials for SCI in humans in that era were facilitated by the common performance of laminectomy as part of the treatment regimen.…”

“…Conversely, Dididze and colleagues 2 systemically and modestly (33°C) cooled patients for 48 hours. This duration was informed 7 by findings from a meta-analysis 10 of controlled trials studying systemic hypothermia for traumatic brain injury. Perhaps the optimal duration of cooling is different for modest hypothermia than for deep hypothermia, with the more profound hypothermia possible in local cooling requiring a shorter duration for maximal effect.…”

Beneficial effects of local profound hypothermia and the possible mechanism after experimental spinal cord injury in rats

“…Of all the methods, hypothermia has been used to protect the central nervous system (CNS) after cardiac arrest hypoxic ischemic encephalopathy, 3 aortic aneurysm surgery, [4][5][6] and spinal cord injury, in many experimental and clinical studies. [7][8][9] However, some controversial issues need to be resolved, such as the temperature range, detrimental consequences, the method of introduction, and the duration of hypothermia. The pathophysiology of SCI is complex and involves both primary and secondary mechanisms.…”