Megadose corticosteroid therapy following experimental traumatic spinal injury

A review of associated controversies surrounding glucocorticoid use in veterinary emergency and critical care

OBJECTIVE

To review the literature in human and veterinary medicine regarding the indications for, efficacy of, and controversies surrounding glucocorticoid (GC) administration in the emergency and critical care (ECC) setting, and to provide an overview of the most commonly used synthetic GC formulations.

MEDICATIONS

Synthetic GCs vary in GC and mineralocorticoid potency, hypothalamic pituitary axis suppression, duration of action, route of administration, and clinical indication for use. Some of the GC compounds commonly used in human and veterinary ECC include hydrocortisone, prednisone, methylprednisolone, and dexamethasone.

INDICATIONS FOR USE

GCs are used in human and veterinary ECC for a variety of disorders including anaphylaxis, acute lung injury/acute respiratory distress syndrome, septic shock, and spinal cord injury. Evidence for morbidity or mortality benefit with administration of GC within these populations exists; however, data are sparse and often conflicting.

ADVERSE EFFECTS AND CONTRAINDICATIONS

Routine use of GC in some conditions such as trauma, hemorrhagic shock, and traumatic brain injury is likely contraindicated. GC use has been associated with hyperglycemia, pneumonia, urinary tract infection, gastrointestinal ulceration, or increased mortality in some populations.

Animal studies in spinal cord injury: a systematic review of methylprednisolone

The objective of this study was to examine whether animal studies can reliably be used to determine the usefulness of methylprednisolone (MP) and other treatments for acute spinal cord injury (SCI) in humans. This was achieved by performing a systematic review of animal studies on the effects of MP administration on the functional outcome of acute SCI. Data were extracted from the published articles relating to: outcome; MP dosing regimen; species/strain; number of animals; methodological quality; type of injury induction; use of anaesthesia; functional scale used; and duration of follow-up. Subgroup analyses were performed, based on species or strain, injury method, MP dosing regimen, functional outcome measured, and methodological quality. Sixty-two studies were included, which involved a wide variety of animal species and strains. Overall, beneficial effects of MP administration were obtained in 34% of the studies, no effects in 58%, and mixed results in 8%. The results were inconsistent both among and within species, even when attempts were made to detect any patterns in the results through subgroup analyses. The results of this study demonstrate the barriers to the accurate prediction from animal studies of the effectiveness of MP in the treatment of acute SCI in humans. This underscores the need for the development and implementation of validated testing methods.

An Appraisal of Ongoing Experimental Procedures in Human Spinal Cord Injury

Clinicians and scientists in the field of spinal cord injury research and medicine are poised to begin translating promising new experimental findings into treatments for people. Advances in experimental regeneration research have led to several transplantation strategies that promote axonal regrowth and partial functional recovery in animal models of injury. In this review, we summarize current knowledge regarding various invasive experimental treatments that have been or are now being applied clinically. Various questions about the timeliness, safety, and benefits of the procedures are under discussion within the spinal cord injury (SCI) research community. We also describe guidelines for carrying out optimal clinical trials and efforts to establish specific international guidelines to translate preclinical treatment strategies into clinical trials in SCI. The clinical trial process and the role that clinical professionals have in advising individuals regarding participation in experimental procedures also is discussed.

Effects of methylprednisolone on the neural conduction of the motor evoked potentials in spinal cord injured rats

Methylprednisolone(MP), a glucocorticoid steroid, has an anti-inflammatory action and seems to inhibit the formation of oxygen free radicals produced during lipid peroxidation in a spinal cord injury(SCI). However, the effects of MP on the functional recovery after a SCI is controversial. The present study was conducted to determine the effects of MP on the recovery of neural conduction following a SCI. A SCI was produced using the NYU spinal cord impactor. A behavioral test was conducted to measure neurological disorders, and motor evoked potentials (MEPs) were recorded. According to the behavioral test, using BBB locomotor scaling, MP-treated animals showed improved functional recoveries when compared to saline-treated animals. MEP latencies in the MP-treated group were shortened when compared to those in the control group. Peak amplitudes of MEPs were larger in the MP-treated group than those in the control group. The thresholds of MEPs tended to be lower in the MP-treated group than those in the control group. These results suggest that MP may improve functional recovery after a SCI.

Tissue expression of 165-aa vascular permeability factor after spinal cord injury is not influenced by dexamethasone administration in rats

Using immunohistochemistry, RT-PCR, and Western Blot techniques, we studied the tissue expression of the 165-aa Vascular permeability factor (VPF) after spinal cord injury (SCI) in adult Wistar rats. The results were compared according to that the animals received or non-dexamethasone, at the dose of 1mg/kg and day after trauma. Furthermore, the different functional recovery between treated and non-treated animals was recorded. Although the administration of dexamethasone showed a beneficial effect on the functional recovery of the animals, the tissue expression of VPF after SCI is not influenced by dexamethasone administration. Therefore, the neuroprotective effect of the dexamethasone after experimental SCI is not mediated through an interference on the biological effects of the 165-aa vascular permeability factor.

Early induction of secondary injury factors causing activation of calpain and mitochondria-mediated neuronal apoptosis following spinal cord injury in rats

To investigate a potential relationship between calpain and mitochondrial damage in spinal cord injury (SCI), a 40 gram-centimeter force (g-cm) injury was induced in rats by a weight-drop method and allowed to progress for 4 hr. One-centimeter segments of spinal cord tissue representing the adjacent rostral, lesion, and adjacent caudal areas were then removed for various analyses. Calcium green 2-AM staining of the lesion and penumbra sections showed an increase in intracellular free calcium (Ca(2+)) levels following injury, compared with corresponding tissue sections from sham-operated (control) animals. Western blot analysis showed increased calpain expression and activity in the lesion and penumbra segments following SCI. Double-immunofluorescent labeling indicated that increased calpain expression occurred in neurons in injured segments. Western blot analysis also showed an increased Bax:Bcl-2 ratio, indicating the induction of the mitochondria-mediated cell death pathway in the lesion and penumbra. The morphology of mitochondria was altered in lesion and penumbra following SCI: mostly hydropic change (swelling) in the lesion, with the penumbra shrunken or normal. At 4 hr after induction of injury, a substantial amount of cytochrome c had been released into the cytoplasm, suggesting a trigger for apoptosis through caspase 3 activation. Neuronal death after 4 hr of injury was detected by a combined TUNEL and double-immunofluoresence assay in the lesion and penumbra sections of injured cord, compared with sham controls. These results suggest that an early induction of secondary factors is involved in the pathogenesis of SCI. The increased Ca(2+) levels could activate calpain and mediate mitochondrial damage leading to neuronal death in lesion and penumbra following injury. Thus, secondary injury processes mediating cell death are induced as early as 4 hr after the injury, and calpain and caspase inhibitors may provide neuroprotection.

Spinal cord contusion models

Most human spinal cord injuries involve contusions of the spinal cord. Many investigators have long used weight-drop contusion animal models to study the pathophysiology and genetic responses of spinal cord injury. All spinal cord injury therapies tested to date in clinical trial were validated in such models. In recent years, the trend has been towards use of rats for spinal cord injury studies. The MASCIS Impactor is a well-standardized rat spinal cord contusion model that produces very consistent graded spinal cord damage that linearly predicts 24-h lesion volumes, 6-week white matter sparing, and locomotor recovery in rats. All aspects of the model, including anesthesia for male and female rats, age rather than body weight criteria, and arterial blood gases were empirically selected to enhance the consistency of injury.

Prognostic indicators for time to ambulation after surgical decompression in nonambulatory dogs with acute thoracolumbar disk extrusions: 112 cases

OBJECTIVES

To determine prognostic indicators for time to ambulation after surgical decompression in nonambulatory dogs with intact pain sensation and acute Hansen type-1 disk extrusions.

STUDY DESIGN

Retrospective clinical study.

ANIMALS

One-hundred twelve dogs with Hansen type-I disk extrusions that had decompressive hemilaminectomy or dorsal laminectomy.

METHODS

All dogs had thoracolumbar disk extrusion and were nonambulatory with intact pain sensation at admission. Variables considered included age, weight, voluntary motor function at time of anesthetic induction, glucocorticoid use, times from onset of nonambulatory status to admission and surgical decompression, time in hospital to surgical decompression, anesthetic time, surgical time, number of contrast injections required to perform a diagnostic myelogram, postoperative pain sensation, and postoperative voluntary motor function. Time to ambulation was defined as the number of days from surgical decompression until the dog was able to stand and take a series of steps without assistance.

RESULTS

One-hundred seven dogs (96%) were able to ambulate within 3 months. The mean time to ambulation was 12.9 days and was significantly shorter if dogs had postoperative voluntary motor function (7.9 days v 16.4 days, P <.0001). No other variable had a significant association with time to ambulation.

CONCLUSIONS

Few perioperative variables have prognostic value for return to ambulation. Nonambulatory dogs with intact pain sensation and Hansen type-1 disk extrusions in the thoracolumbar spine that are treated with surgical decompression have a favorable prognosis.

CLINICAL RELEVANCE

The presence of postoperative voluntary motor function is a favorable prognostic indicator for early return to ambulation.

Methylprednisolone and interleukin-10 reduce gray matter damage in the contused Fischer rat thoracic spinal cord but do not improve functional outcome

The effects of two antiinflammatory and neuroprotective agents, methylprednisolone (MP) and interleukin-10 (IL-10), singly and in combination on tissue damage, axonal preservation and functional recovery were studied in the contused adult Fischer rat thoracic spinal cord 12 weeks after injury. MP (30 mg/kg at 5 min, and 2 and 4 h after injury) was administered intravenously and IL-10 (15 or 30 microg/kg at 30 min after injury), intraperitoneally. MP, IL-10, or the combination significantly reduced the volume of damaged tissue (including cavities) compared to control animals. The loss of spinal tissue (cavities) was reduced after treatment with MP alone or combined with IL-10, but not with IL-10 alone. The reduction in tissue damage was confined to spinal gray matter; at the level of the lesion epicenter, the thickness of the lateral white matter columns was similar in all groups. Retrograde tracing using fast blue revealed that the number of spared propriospinal and supraspinal projections was similar in all groups at 12 weeks after the contusion. The open-field BBB-test showed no significant difference in hindlimb locomotion between groups. Our results demonstrate that all tested antiinflammatory treatments significantly increase the volume of spared spinal gray matter 3 months after a moderate contusion of the Fischer rat thoracic spinal cord, but none of the treatments improved axonal preservation or functional recovery.

The early protective effects of L-arginine and Ng-nitro-L-arginine methyl ester after experimental acute spinal cord injury. A light and electron microscopic study

The purpose of this study was to investigate the early protective effects of L-arginine and Ng-nitro-L-arginine methyl ester (L-NAME) after acute spinal cord injury. Acute spinal cord injury was performed by epidural application of an aneurysm clip at thoracic (T) 7 - 11 level. L-arginine at a dose of 750 microg/kg/min was administered 10 min before acute spinal cord injury and continued for 30 min to 10 animals (Group II). L-NAME at a dose of 250 microg/kg/min was administered 10 min before acute spinal cord injury and continued for 30 min to 10 animals (Group III). No drug was administered to 10 animals after acute spinal cord injury (Group I). Light and electron microscopic analysis were performed in all of the groups. Oedema of perineural, axoplasm or white matter in the L-arginine-treated group was less than in Group I and Group III. Thickening in the walls of the arterioles and venules in the L-arginine-treated group was much milder than in Group I and Group III. Degeneration of myelinated axons in the L-arginine-treated group was milder than in the control group. But there was no different between Group II and Group III.

Somatosensory spinal cord evoked potentials in the evaluation of the effect of dexamethasone in experimental spinal cord injury

We studied the effects of high-dose dexamethasone on amplitude and latency values of spinal cord evoked potentials. Thirty-three rabbits were divided into three equal groups. The first group served as the control group, the others received high-dose (2.5 mg/kg) dexamenthasone, the second group 1 hour prior to and the third group immediately after the induction of a spinal cord trauma in segment T12. The spinal cord evoked potentials were recorded epidurally from T12 segment 5 min before and 5, 30, 60, 90, 120 and 150 min after trauma. Pretreatment with dexamethasone (group II) prevented the latency delay, and later treatment with dexemethasone (group III) prevented the latency delay partially. Our results suggest that when dexamethasone is given prophylactically it prevents latency alteration, while treatment with dexamethasone after lesioning prevents latency alteration partially. From our results we conclude that pretreatment with dexamethasone may involve different mechanisms than were activated in the posttreatment group.

The effects of chronic alpha-tocopherol administration on lipid peroxidation in an experimental model of acute spinal cord injury

Most of the numerous experimental studies to research pathophysiological changes following acute spinal cord injury suggest a two-step mechanism of damage to the spinal cord in which the primary (direct) or mechanical injury caused by the trauma initiates secondary (indirect) or progressive autodestructive injury of the cord. During recent years, free oxygen radical generation and lipid peroxidation have been considered to be responsible for secondary autodestructive injury. Alpha tocopherol occupies an important and unique position in the overall antioxidant defense. Alpha tocopherol-depleted animals are generally more susceptible to the adverse effects of environmental agents than are supplemented animals. This study was planned to study the effectiveness in counteracting this autodestructive process by supplementing alpha-tocopherol in rats maintained on a nutritionally adequate diet, and also to evaluate whether it will provide additional protection or not. Eighty healthy Wistar rats (treatment and controls) were included. The treatment group received 100 mg/kg alpha tocopherol each day, intraperitoneally for seven days. Using a standard acute spinal cord trauma model in Wistar rats trauma was applied, an malondialdehyde (MDA) which is a lipid peroxidation product was measured in the traumatized spinal cord at various times following the trauma in order to indirectly evaluate the lipid peroxidation and generation of free oxygen radicals in a time sequence. Statistical analysis of the values demonstrated that malondialdehyde formation in the alpha-tocopherol administered group was significantly lower than in the control group. These findings indicate that longterm administration of alpha-tocopherol may be useful to decrease lipid peroxidation following acute spinal cord trauma.

Use of methylprednisolone as an adjunct in the management of patients with penetrating spinal cord injury: outcome analysis

OBJECTIVE

Since the results of the Second National Acute Spinal Cord Injury Study were published in 1990, methylprednisolone has become a mainstay in the treatment of nonpenetrating spinal cord injury. Although potential significant relationships between the prompt administration of high-dose methylprednisolone after blunt spinal cord injury and outcome have recently been addressed, the relationship between the prompt administration of high-dose methylprednisolone after penetrating spinal cord injury and outcome remain unanswered.

METHODS

To explore this relationship, we performed a retrospective nonrandomized study on a series of 252 patients with penetrating missile injuries to the spine who presented to our institution from March 1980 to July 1993. One hundred eighty-one patients (71%) were treated conventionally without adjunctive steroid therapy before 1990. Sixteen patients followed up during the 13-year study period received steroid protocols that were not consistent with the Second National Acute Spinal Cord Injury Study protocol and were excluded from the study. Since 1990, 55 patients (21%) were treated with intravenous methylprednisolone according to the Second National Acute Spinal Cord Injury Study protocol. All patients were subsequently transferred for rehabilitative care, and prospective evaluations of their neurological status were performed at admission and discharge.

RESULTS

The study included 236 men and 16 women (mean age, 25.6 yr). The mean duration of stay for initial hospitalization was 94.6 days, and the mean duration of stay in rehabilitation was 78.6 days. Frankel scores were used to assess outcome (P < 0.05) and were assessed at admission and at the time of definitive discharge from the Spinal Cord Injury Care System. The hypothesis that methylprednisolone therapy significantly improves functional outcomes in patients with gunshot wound injuries to the spine was rejected. Only the total number of days in rehabilitation and the degree of neurological injury at admission contributed significantly to explaining outcome at discharge.

CONCLUSION

The administration of methylprednisolone did not significantly improve functional outcomes in patients with gunshot wound injuries to the spine or increase the number of complications experienced by patients during their hospitalizations.

Treatment of patients with severe head injury by triamcinolone: a prospective, controlled multicenter clinical trial of 396 cases

The present studies were conducted to test whether the outcome of severe head injury is improved by early administration of the synthetic corticosteroid triamcinolone. In a prospective, double-blind, multicenter clinical trial, 396 patients with severe head injury were randomized to a steroid group (n = 187) receiving 200 mg triamcinolone acetonide (Volon A soluble) i.v. within 4 h after trauma, followed by 3 x 40 mg/day i.v. for 4 days, and 3 x 20 mg/day i.v. for a further 4 days, and a placebo group (n = 209) receiving injections which did not contain any active drug. The placebo group was subjected to the same standard treatment procedures. Clinical features were not different between the groups upon admission to hospital. Subdural hematoma, epidural hematoma, and focal supratentorial contusion were among the most frequent diagnoses. The result of treatment with triamcinolone was assessed at discharge from the hospital and at 1 year after trauma, using the Glasgow Outcome Scale. Differences in favor of steroid treatment could be detected with regard to the patients' condition at discharge (P = 0.0634). More patients with steroids had a good recovery (49.2% vs 40.7%), and fewer died (16.0% vs 21.5%). Differences in outcome were even more pronounced (P < 0.0145) in patients with a focal lesion and a Glasgow Coma Score on admission of < 8 (n = 93). In this group, 34.8% of the patients made a good recovery, as against 21.3% of the placebo group; mortality was also lower in the verum group (19.6% vs 38.3%). The results indicate that a major subgroup of patients with severe head injury benefits from early administration of triamcinolone. Efficacy of the treatment can be expected, in particular, in patients with a focal cerebral lesion and a Glasgow Coma Score of < 8 on admission. Administration of steroids beginning at the scene of an accident would therefore be beneficial in these cases.

Traumatic optic neuropathy

Knowledge concerning the pathophysiologic mechanisms of traumatic optic neuropathy is limited. The optic nerve is a tract of the brain. Therefore, the cellular and biochemical pathophysiology of brain and spinal cord trauma and ischemia provide insight into mechanisms that may operate in traumatic optic neuropathy. The dosage of methylprednisolone (30 mg/kg/6 hours) which was successful in the National Acute Spinal Cord Injury Study 2 (NASCIS 2) evolved from the unique pharmacology of corticosteroids as antioxidants. The management of traumatic optic neuropathy rests on an accurate diagnosis which begins with a comprehensive clinical assessment and appropriate neuroimaging. The results of medical and surgical strategies for treating this injury have not been demonstrated to be better than those achieved without treatment. The spinal cord is a mixed grey and white matter tract of the brain in contrast to the optic nerve which is a pure white matter tract. The treatment success seen with methylprednisolone in the NASCIS 2 study may not generalize to the treatment of traumatic optic neuropathy. Conversely, if the treatment does generalize to the optic nerve, NASCIS 2 data suggests that treatment must be started within eight hours of injury, making traumatic optic neuropathy one of the true ophthalmic emergencies. Given the uncertainties in the treatment, ophthalmologists involved in the management of traumatic optic neuropathy are encouraged to participate in the collaborative study of traumatic optic neuropathy.

Spinal cord blood flow and evoked potential responses after treatment with nimodipine or methylprednisolone in spinal cord-injured rats

This study examined the effect of nimodipine or methylprednisolone on spinal cord blood flow (SCBF) and electrophysiological function after spinal cord injury in rats. Three groups of male rats (n = 10 per group) were injured by compression of the cord at T1 for 1 minute with a 52-g clip. The hydrogen clearance technique was used to measure SCBF at the T1 segment. Motor and somatosensory evoked potentials were recorded. SCBF and evoked potentials were measured before injury and again at approximately 1 and 2.5 hours after injury. The methylprednisolone group received a bolus of methylprednisolone (30 mg/kg) at 5 minutes after injury and then at 15 minutes after injury, the group received an infusion of methylprednisolone at 5.4 mg/kg per hour. The nimodipine group received placebo at 5 minutes and then received an infusion of nimodipine at 0.02 mg/kg per hour at 15 minutes. The placebo group received placebo at both times. Physiological parameters were closely monitored and maintained within the normal range. Albumin was administered after injury to maintain mean arterial blood pressure at or above 80 mm Hg. The infusions were continued for approximately 3 hours after spinal cord injury. SCBF was not significantly different between the experimental groups at either 1 or 2.5 hours postinjury (P = 0.16 and 0.71, respectively), and evoked potential responses did not return in any rat at any time after injury. Thus, this experiment failed to demonstrate an improvement in SCBF or electrophysiological function with either drug.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of methylprednisolone on motor function and spinal cord blood flow after spinal cord compression in rats

The effect of methylprednisolone (MP) on neurologic recovery and spinal cord blood flow (SCBF) was investigated up to 4 days after a spinal cord compression injury in rats. The injury was produced at midthoracic level by applying a load of 35 g on a 2.2 x 5.0 mm compression plate for 5 min, which resulted in transient paraparesis. MP was given as a bolus dose of 30 mg/kg i.v. 60 min after injury (n = 20) and controls were given saline (n = 10). The motor performance was assessed daily as the capacity angle on the inclined plane and SCBF was measured by 14C-iodoantipyrine autoradiography on Days 1 or 4. On Day 1 the capacity angle was reduced from about 63 degrees preoperatively to 33 +/- 2 degrees (mean +/- SEM) in the control group and to 50 +/- 1 degrees in the group treated with MP (p less than 0.05). Thereafter there was a slight improvement in both groups, but the difference persisted throughout the observation period. On Day 4 both gray and white matter SCBF was better preserved in MP-treated animals than in the control group (59 +/- 4 versus 49 +/- 3 ml/min/100 g tissue for gray matter and 13.6 +/- 0.6 versus 10.7 +/- 0.8 ml/min/100 g tissue for white matter). Posttraumatic treatment with MP, thus, improved both the neurologic recovery during the first 4 days and SCBF as measured on Day 4. It is speculated that the effect of MP is at least partly exerted on the vascular bed.

Dose- and time-dependent effects of dexamethasone on rat brain following cold-injury oedema

Experiments were carried out with a rat model of brain-injury oedema to establish the most efficacious dose and administration schedule for dexamethasone treatment. The results indicate that there are statistically significant dose- and time-dependent effects for dexamethasone treatment of cold-injury oedema. The equivalent of a 500 mg dose of dexamethasone had the highest anti-oedematous effect. With higher doses no further improvement could be achieved and the potential of hazardous effects increased. As expected, pretraumatic drug treatment had the greatest therapeutic effect. Dexamethasone administration up to about 30 min after cold injury led to measurable beneficial results. Drug injection from 90 min or longer after injury only slightly reduced cerebral oedema. No therapeutic effects were found when dexamethasone was administered more than 21 hours after inducing cerebral oedema. If similar results are obtained in corresponding clinical studies, the recommended dexamethasone dose and schedule for treating traumatic cerebral oedema would be: 1) high doses of drug (e.g. 500 mg); 2) drug administration to begin as early as possible, preferably within the first 2-3 hours after head injury; and 3) treatment should be terminated within 2-3 days to avoid major side effects.

Evaluation of an intensive methylprednisolone sodium succinate dosing regimen in experimental spinal cord injury

Beginning 30 minutes after compression trauma of the upper lumbar (L-2) spinal cord, cats were treated with either a high-dose regimen of methylprednisolone (MP) administered as the sodium salt of the 21-succinate ester (Solu-Medrol sterile powder) or the MP vehicle. Animals were randomly assigned to either treatment group (10 cats per group), and all personnel were blind as to which animals received vehicle or drug. The intensive 48-hour dosing regimen was designed to maintain therapeutic tissue levels of MP and consisted of an initial 30 mg/kg intravenous bolus of MP; 2 and 6 hours later additional 15 mg/kg MP doses were administered by intravenous bolus. Immediately following the bolus given at 6 hours, a continuous MP infusion of 2.5 mg/kg/hr was started. The infusion was stopped abruptly at 48 hours with no dose tapering. Animals in the vehicle group received an equivalent volume of MP vehicle. The total MP dose administered over 48 hours was 165 mg/kg. Animals were evaluated weekly for neurological recovery based upon a 12-point functional scale which assessed general mobility, running, and stair-climbing. Mean recovery scores at 1 month after injury (+/- standard error of the mean) were: vehicle group (seven cats) 3.7 +/- 0.9, and MP group (10 cats) 8.7 +/- 0.2; (p less than 0.001). Histological evaluation of the spinal cords revealed a strong negative correlation between neurological recovery and size of the spinal cord cavity at 1 month (r = -0.88). Three of 10 animals in the vehicle group became ill and had to be dropped from the study, whereas all of the 10 MP-treated animals survived in excellent health. The results demonstrate the therapeutic effectiveness and low incidence of side effects associated with an intensive MP dose regimen for treatment of experimental spinal cord injury.

Reflections on the intensive care of 106 acute cervical spinal cord injury patients in the resuscitation unit of a general traumatology centre

This presentation deals with an 11 year survey of 106 cervical spinal cord injuries, admitted immediately after injury or during the very acute phase, to the Traumatology Resuscitation Unit of Colmar, (France). A preliminary report concerning 51 patients was published in 1979. The follow-up study concerns a further 55 cervical spinal cord injured patients admitted from January 1979 to December 1984. The emphasis of our presentation concerns the frequency of some of the main complications and their attempted prevention: the haemodynamic disturbances caused by over-hydration; the prevention of haemorrhagic stress ulcers is not only by the use of specific drugs, but mainly by immediate intravenous adequate caloric nutrition. This can be associated with, or followed as soon as possible by, an adapted caloric diet, possibly by a naso-gastric tube. For serious respiratory complications, artificial ventilation even for long periods as discussed, by nasal intubation or in some patients tracheotomy.

Acute effects of dexamethasone on normal and on posttraumatic spinal cord polysynaptic reflex activity and axonal conduction

The effects of a single intravenous injection of a high dose of dexamethasone (4 mg/kg) on polysynaptic reflex activity and axonal conduction were measured for 5 hours in the intact and in the compression-injured L-7 spinal cord segment of high spinal cats. The segment was injured by a transient compression of preset degree and duration. In the uninjured preparation, dexamethasone administration significantly reduced polysynaptic reflex size for 2 hours. Axonal conduction was unaltered. One group of injured animals was given dexamethasone 30 minutes after trauma, whereas another was not treated. The acute posttraumatic changes in both parameters did not differ significantly in treated and untreated animals. Histopathologically, differences in the amount of segmental edema and hemorrhage between untreated and treated animals were not significant.

Septic complications of corticosteroid administration after central nervous system trauma

The records of 197 consecutive multiple trauma patients were reviewed to define the infectious complications of corticosteroids used to treat brain and spinal cord injury. An injury severity score (ISS) and a central nervous system (CNS) injury score were determined for each patient. Patients with an ISS less than 20 did well with or without steroids and were excluded from further study. All deaths that occurred 5 or more days after injury were caused by sepsis, and all occurred in steroid recipients. Twenty-nine of 61 steroid-treated early survivors developed infectious complications, compared to eight of 55 patients who did not receive steroids (47.5% vs. 14.5%, p less than 0.001). There was no correlation between severity of CNS trauma and infectious complication rate. Steroid-treated patients frequently developed multiple pathogen primary infections and multiple, simultaneous septic foci. Patients treated with steroids more often developed infections caused by Staphylococcus aureus, assorted gram negative rods, anerobic bacteria, or fungi. The study strongly suggests a significant increase in both the incidence and severity of infectious complications occurring in patients treated with corticosteroids for CNS trauma.

Current application of "high-dose" steroid therapy for CNS injury. A pharmacological perspective

Although administration of glucocorticoid steroids is one of the most widely used therapeutic modalities for the clinical management of acute trauma of the central nervous system (CNS), controversy continues regarding their effectiveness. In essence, two viewpoints concerning their use exist. Some believe that despite their poor clinical record, the steroids nevertheless have a place in the treatment of human CNS trauma. In general, this group of clinical investigators uses the steroids primarily out of tradition, feeling that steroid therapy may be of some benefit. Unfortunately, confusion remains as to what constitutes an appropriate dose or regimen. In this regard, it has been suggested that the steroid dose be increased and the regimen intensified. Others believe that steroids should not be used. They contend that in view of their poor clinical record, it is unlikely that increasing the steroid dose or changing the dosing regimen will improve clinical efficacy, since steroids have already failed at what may be considered huge doses by glucocorticoid standards. Furthermore, it is contended that the side effects associated with large steroid doses reduce the margin of safety so as to make the steroids unsafe. Complicating these arguments is a body of experimental evidence that by and large strongly supports the utility of steroids for the acute treatment of CNS trauma. The intent of this article is to evaluate the current use of steroid therapy for CNS trauma from a purely pharmacological perspective, and to compare the steroids' experimental use with their clinical application.

Prevention of postoperative facial edema with steroids after facial surgery

A one-bolus (dose) of 1 g of methylprednisolone was administered intravenously to patients undergoing facial surgery or craniofacial surgery, before the termination of the operative procedure. The degree of facial edema noted was reduced, and when it occurred, it was mild and of shorter duration. These observations were made on the experimental design first, and later in the clinical setting. No adverse effects were noted, and patients given this treatment required less pain medication in the immediate postoperative period. The mechanism of action of the steroids is multifactorial, related to decrease in the accumulation of fluid at the capillary level, and reduction of flow at the venoarterial sphincters. The use of steroids is safe when used with caution in selected patients, and by experienced surgeons.

The therapeutic effects of drugs in injured central nervous system

A variety of physiologic, neurochemical, and morphologic sequelae have been either shown or postulated to result from spinal cord injury, yet the actual pathophysiologic substrate that leads to the loss of neurologic function remains uncertain. Several treatment modalities have been investigated in spinal cord injury, but little consensus exists regarding their efficacy. Steroids in particular have been studied extensively with little agreement about their effects and possible mechanism of action. Recently naloxone has been found to improve neurologic function following spinal cord injury, and its effectiveness has not been challenged to date. In the past most attempts at therapy in cases of brain injury were directed at control of edema, and, consequently, clinically beneficial effects were usually ascribed to control of the edematous process. This was particularly so in the case of steroids. Currently, emphasis has shifted to the study of various neurochemical systems (eicosanoids, serotonin, catecholamines) that, independently from edema may underlie functional disturbances resulting from trauma. Much of the pertinent information derives from the use of drugs in freezing lesion models of brain injury.