Compositions and treatment method for brain and spinal cord injuries

Abstract

Cerebral edema is the final common pathway for all CNS tissue injuries. The CSF is the major player for cerebral edema and the resultant blood perfusion deficit. A composition and method for treating injured central nervous tissue, or preventing injury to central nervous system tissue is provided. The composition includes two washing solutions, a first solution comprising an emulsion of oil, water, at least one osmotic agent and at least one emulsifier; the second solution comprising a pre-emulsion comprising water, oil, at least one osmotic agent, and at least one emulsifier. The method provides for withdrawing a volume of cerebrospinal fluid from the subarachnoid space and flushing the subarachnoid space with one or both washing solutions. Other materials may be added to the solutions to treat or prevent injury to nerve tissue resulting from injury or interruption of circulation.

Description

RELATED APPLICATIONS

[0001] This application is a continuation in part of application Ser. No. 09/962,009, filed Sep. 24, 2001, the disclosure of which is hereby incorporated by reference.

BACKGROUND OF THE INVENTION

FIELD OF THE INVENTION

[0002] This invention is related to medical formulations used to treat and protect the brain and spinal cord and methods of using those formulations. In particular, the invention relates to neuroprotective formulations and methods using those formulations to protect the brain and spinal cord or minimize lasting damage.

BACKGROUND INFORMATION

[0003] Central Nervous System (CNS) tissue including brain and spinal cord is very vulnerable to injuries. For example, the brain is believed to tolerate complete interruption of blood flow (such as cardiac arrest) for a maximum of about 5 to 10 minutes.

[0004] Most CNS injuries, including stroke, trauma, hypoxia-ischemia, multiple sclerosis, seizure, infection, and poisoning directly or indirectly involve a disruption of blood supply to the CNS, and share the same common pathologic process, that is: rapid cerebral edema leading to irreversible brain damage, and eventually to brain cell death.

[0005] It has been known that after cardiac arrest and global ischemia, the brain suffers a “no-reflow” phenomenon. In the 1960s, Ames produced global cerebral ischemia for 6 minutes in rabbits followed by carbon black ink infusion. He found that a large amount of the brain suffered from perfusion deficits. Similar to the “no-reflow’ phenomenon, post-ischemic or post-traumatic “hypoperfusion” has also been documented after spinal cord and brain injuries.

[0006] Our scientific community is familiar with hydrocephalus and cytotoxic, vasogenic cerebral edema, yet the CSF itself, the huge water resource, has seldom been linked with cerebral edema and the vulnerability of the brain and spinal cord to injuries. In an adult human, the CSF volume ranges from about 52 to 160 ml (mean 140 ml), occupying 10 percent of the intra-cranial and intra-spinal volume. The average rate of CSF formation is about 21 to 22 ml/hr. To date, there is no definite evidence suggesting that the CSF is actively involved in the metabolism of the cells of the brain and spinal cord. The known primary function of CSF appears to be a mechanical one; it serves as a kind of water jacket for the spinal cord and brain, protecting them from potentially injurious blows to the spinal column and skull and acute changes in venous pressure. It also serves as a buoyancy so that the brain and spinal cord virtually float in a CSF jacket with weight being greatly reduced. The potential influence of the CSF during the CNS injuries has not been fully investigated.

[0007] Clinical treatment for CNS injury induced edema including intravenous administration of osmotic agent, diurtic, removal of cerebrospinal fluid, coticosterroids, however, the efficacy is temporary and limited. Current search for a neuroprotective treatment has yielded a disappointing result including oxygen free radical scavengers, calcium channel blockers and glutamate receptor antagonists to monoclonal antibodies that attempt to curtail inflammatory cascades occurring in cerebral injuries.

[0008] Current treatments for stroke include recombinant tissue plasminogen activator (rt-PA), a thrombolytic agent, that has been shown to be effective dissolving clots to restore blood flow to injured areas of the brain if used within 3 hours after the onset of the stroke.

[0009] U.S. Pat. No. 5,755,237 to Rodriguez discloses acetazolamide for the treatment of brain edema. Acetazolamide can inhibit cerebrospinal fluid production, but administering of acetazolamide alone does not have a neuroprotective effect.

[0010] A series of patents, U.S. Pat. Nos. 4,981,691, 4,758,431, 4,445,887, 4,445,500, and 4,393,863 to Osterholm disclose a fluorocarbon solution for treatment of hypoxic-ischemic neurologic tissue.

[0011] U.S. Pat. No. 6500,809 to Frazer Glenn discloses a hyperoncotic artificial cerebrospinal fluid and method of treating neural tissue edema.

SUMMARY OF THE INVENTION

[0012] Cerebral edema is a common pathway for all CNS injuries. Clinical treatment for CNS injury induced edema including intravenous administration of osmotic agent, diurtic, removal of cerebrospinal fluid, coticosterroids, however, the efficacy is temporary and limited. Current search for a neuroprotective treatment has yielded a disappointing result.

[0013] I have discovered that the cerebrospinal fluid (CSF) is one of the major reasons why CNS tissue is so vulnerable to injuries. Elimination of this CSF induced cerebral edema prevents the onset of the ‘no-reflow” phenomenon or “hypoperfision”, enabling blood to reperfuse the damaged CNS tissue. Therefore, Eliminating the CSF can protect the CNS tissue making it resistant to injuries, and lengthening the therapeutic window for all other therapies. I have invented two washing solutions. The first washing solution is water in oil emulsion with higher osmotic pressure. It can act as a hook to pull out edematous CSF fluids away from the CNS tissue into the oil. The second solution is a pre-emulsion comprising oil and emulsifiers, while further removing the water from the first washing solution, it also provides insulation in case of new CSF coming back. I have found that the invented washing solutions is effective to protect and prevent the CNS tissue damage when it is applied to the subarachnoid spaces

[0014] This invention provides compositions and methods for protecting brain and spinal cord from injuries. Compositions according to this invention may be used to treat neurological disorders, such as stroke, hypoxia-ischemia, hemorrhage, trauma, multiple sclerosis, seizure, infection, or poisoning. The compositions are also useful during open-heart surgery, aortic surgery, neurosurgery, shock, or other procedures where blood flow to the CNS is interrupted.

[0015] There are many advantages to the compositions and method I have discovered.

[0016] One advantage is it provides an effective treatment and prevention for CNS tissue injuries.

[0017] It also improves the efficacy of existing treatments for stroke, head trauma, and other invasive procedures. Administering an effective solution according to this invention will increase the therapeutic window, the period of time in which any other treatment, including thrombolytic agents can be used. For example, tPA, the only FDA approved medication for stroke, is a thrombolytic agent targeted on dissolving the blood clots that led to the stroke. tPA is now only approved for use within 3 hours after onset of ischemia. When used in combination with the instant composition and method, the therapeutic window for all known treatments now used for supporting CNS tissue will be much longer.

[0018] This invention, if combined with other known techniques such as controlled hypothermia, may significantly increase the length of time a patient can tolerate cerebral ischemia. A patient treated according to this invention may survive invasive procedures performed on any part of the CNS without injury, including areas of the brain that have not been surgically accessible prior to this invention. Additionally, procedures that require interruption of the blood flow, such as heart surgery, repair of aortic aneurysm, or any other surgery where systemic blood circulation is interrupted can be performed with increased safety.

[0019] The compositions and methods I have invented extend the therapeutic window for successfully recovering from a stroke or cardiac arrest from mere minutes to hours.

[0020] In addition, this compositions and method are useful for screening neuroprotective agents developed based on other mechanisms. The compositions and methods also can enhance the effectiveness of other neuroprotective agents.

DETAILED DESCRIPTION OF AN ILLUSTRATIVE EMBODIMENT

[0021] In ischemic injury, CSF has a toxic effect of facilitating cerebral edema. While intracellularly excessive water content is directly toxic to the CNS cells, the cerebral edema can also block cerebral blood flow and collateral circulation to damaged nerve tissue, causing the “no-reflow” phenomenon or “hypoperfusion”. This failure of circulation results in continuing damage to CNS tissue after the interruption of blood flow is reversed leading to irreversible damage. Restoration of blood flow to the affected area of the CNS after a period of complete ischemia as short as six minutes does not result in blood re-flow to the affected CNS tissue. After the CNS tissue is injured by an initiating insult, such as ischemia, trauma, the CSF infiltrates the CNS tissue through water channels on the injured cell membrane to cause edema. Swelling of the tissue makes the Virchow-Robin space (also known as the perivascular space or extracellular space) smaller and may even cause it to collapse, thereby compressing the small blood vessels and resulting in a obstruction of the blood flow, such as a “hypoperfusion” or even “no-reflow” phenomenon, which prolongs the original ischemic duration, blocks collateral circulation and induces a feedback loop. As the duration of blood flow interruption increases, the edema spreads throughout the CNS tissue causing additional damage in an ischemic cascade.

[0022] In the adult human, the average intra-cranial volume is about 1700 ml. The volume of the brain is approximately 1400 ml; CSF volume ranges from about 52 to about 160 ml (mean 140 ml), and blood volume is about 150 ml. Thus, the CSF occupies about 10 percent of the intra-cranial and intra-spinal volume.

[0023] The choroid plexuses are the main sites of CSF formation. The average rate of CSF formation is about 21 to 22 ml/hr, or approximately 500 ml/day. The CSF as a whole is renewed four or five times daily. CSF formation is related to intracranial pressure. When the intracranial pressure is below about 70 mm H2O, CSF is not absorbed, and production increases. CSF is a very dilute aqueous solution with a low colloidal osmotic pressure.

[0024] The CSF has a mechanical function. It serves as a kind of water jacket for the spinal cord and brain, protecting them from trauma and acute changes in venous blood pressure. The CSF provides buoyancy and shock absorption, so that brain and spinal cord float in a CSF pool. CSF does not appear to be necessary to brain or spinal cord metabolism. However, during ischemic episodes, CFS has a toxic effect by facilitating cerebral edema and the resulting in no-reflow phenomenon after disruption of blood flow to CNS tissue.

[0025] The mechanism of injury leading to brain edema is not fully understood. The recent discovery of water channels in the CNS provides a better explanation. Aquapprin-1 (AQP1), Aquapprin-4 (AQP4), Aquapprin-5 (AQP5), Aquapprin-9 (AQP9) water channels have been identified in CNS, and believed to play an important role in the development of cerebral edema. The subarachnoid space is just like a reservoir containing the CSF water providing endless water supply for the CNS tissue. When injury occurs, CSF readily available to penetrate CNS tissues through water channels, while intracellular water unbalance exert direct toxicity to cells, swelling of the tissue around the Virchow-Robin space results in “hypoperfusion” or even “no-reflow” phenomenon, which prolongs the original ischemic duration, blocks collateral circulation and induces a feedback loop. The CNS injuries may be either global, in the case of general failure of blood circulation after a cardiac arrest, or local over an area of any size after for example, a head trauma, an intra-cerebral hemorrhage, or a stroke. Whatever the causes, the CNS edema is the final common pathway and should be controlled in the first place.

[0026] In order to prevent cerebral edema, and the irreversible effects that occur after the CNS injuries, the CSF is withdrawn from the affected area of the CNS. It is preferred to completely remove all CSF from the injured area. It is advantageous to completely remove all CSF from the CNS. However, it is very difficult, almost impossible, mechanically to remove CSF completely from the subarachnoid spaces because the CNS (i.e. brain and spinal cord) contour is very complex with many sulci, gyri and pools. Even if the intra cranial pressure is mechanically reduced below zero, surface tension and capillary forces retain CSF in the spaces between the dura and the cerebral surface. Most importantly, the CSF is retained in the Virchow-Robin space, surrounding smaller vessels that penetrate into the brain from the periphery.

[0027] Mechanically withdrawing CSF alone is not sufficient enough to achieve the neuroprotective effect. This residual aqueous CSF after manual withdrawal can still cause edema and resultant “hypoperfusion” or “no-reflow” phenomenon, significantly decreasing the protective effect because it is a continued source of edematous fluid that can cause delayed or recurring injury. Removing the residual CSF is necessary to maximize the neuroprotective effect.

[0028] In this method, the CSF is withdrawn from the cerebral circulation through one or more cannulas. For maximum CNS tissue protection, two small holes are drilled on the skull, the dura is punctured, and a cannula is placed in through the dura into the subarachnoid spaces. Additional cannulas may be inserted into the lateral cerebral ventricles, the lumbar theca, and the cistema magna. The CSF can be removed from any or all of these locations to remove edematous fluid.

[0029] For the treatment or prevention of a spinal cord injury, a cannula may be placed through a puncture in the lumbar theca or cisterna magna. Optionally, two cannulas may be used.

[0030] CSF pressure control has been used for protecting spinal cord during aortic surgery. It is said that controlling the pressure of CFS, in particular, maintaining a pressure lower than the central venous pressure could be advantageous in protecting the spinal cord from injury during aortic surgery. However, such pressure control does not achieve the neuroprotective effect in the case of more general ischemia. Removing CSF from the spinal cord's subarachnoid space is relatively easier (compared with from brain) because of spinal cord's simpler contour. However, simple withdrawal of CSF even under controlled conditions in thoracoaortic surgery, is not predictably effective protecting CNS tissue.

[0031] As discussed above, the CSF performs a support and shock absorbing function, accordingly some liquid medium is necessary to support the CNS tissues in the body. In addition to provide a support media for the CNS tissues, the liquid should be able to exert function of absorbing and pulling water from the edematous tissue, particularly in sulci, gyri, pools and the Virchow-Robin space.

[0032] In the instant method, the CSF (usually 5-200 ml) is withdrawn from the cranium and spinal cord. As discussed above, it is necessary to remove the CSF as completely as possible for a general CNS injury such as cardiac arrest or for prevention form CNS injury during the cardiac surgery, but for a localized injury, or for prevention of a localized injury during neurosurgery or aortic surgery, beneficial effects can be achieved upon removal of a lesser volume of the CSF.

[0033] After the CSF has been withdrawn, the injured CNS tissue is washed with washing solutions.

[0034] The first washing solution is an emulsion. It should contain oil, an osmotic agent, water and at least one emulsifier. Typically, the emulsion contains up to about 31-80% oil. Generally a water in oil emulsion is preferred. However, oil in water emulsions have also been effective. Intralipid solutions (10%, 20% and 30%), used clinically for parental nutrition, such as those manufactured and distributed by Baxter, Fresenius Kabi, Pharmacia & Upjohn etc may also be effective. The first washing solution acts as a hook to pull out edematous CSF fluids away from the CNS tissue into the oil. The oil can be any non-toxic, organic liquid. Hydrocarbon oils and silicone oils are effective. Any hydrocarbon oils from plant, animal sources and mineral oil such as soybean oil, cod liver oil, vitamin E oil, olive oil, canola oil, corn oil, and mixtures of these oils in any concentration ratio may be used.

[0035] Monoglycerides are oily emulsifiers that can be used alone or with additional emulsifiers. An emulsifier is generally any organic molecule having both a polar functional group, such as a carbonic acid, phosphate, or other polar functional group at one end, and a non-polar, hydrocarbon functional group at another end. Examples of the emulsifiers used in this composition include, but not limited to, amphipathic lipids, such as phosphoglycerides, sphingomyelins, glycolipids, cholesterol, cholesterol hemisuccinate, sphingolipids, cerebrosides and fatty acids. Emulsifiers used in this composition can also include surface active agents such as polyoxyethylene sorbitan fatty acid esters (Tween), Sorbitan Monostearate (Span), Octylphenoxypolyethoxy (Triton), monoglycerides. Many osmotic agents can be chosen, such as glucose, mannitol, glycerin, saccharide, polysaccharide, starch (amylose, amylopectin), protein (both from vegetable and animal sources). Clinically available osmotic agents are preferred.

[0036] The emulsifier may include: soaps, conventional cationic surfactants, or nonionic surfactants, fatty acids, fatty acid salts, monoglycerides, didodecyldimethylammonium bromide, benzalkonium chloride, Amine alkylbenzene sulfonate (Trade Name: NINATE 411), Poly(oxyethylene-co-oxypropylene) block polymer (Trade Name: Pluorinic F68), Telomer B monoether with polyethylene glycol (Trade name: Zonyl FSN 100), Sodium dioctylsulfosuccinate (Trade name: Aerosol OT 100%), Sodium N-oleyl-N-methyltaurate (Trade name GEROPON T-77), Sodium olefin(C(14)-C(16)) sulfonate (Trade name BIO-TERGE AS-40), Sodium polyoxyethylene(1) lauryl sulfate (Trade name STANDAPOLES-1), Benzalkonium (C(8)-C(18)) chloride Ethylenediamine alkoxlate block copolymer (Trade name, Tetronic 1307), 2,4,7,9-Tetramethyl-5-decyne-4,7-diol ethoxylate (10) (Trade name: Surfynol 465), 2.4.7.9-Tetramethyl-5-decyne-4,7-diol ethoxylate (30) (Trade name: Surfynol) 485), Octylphenol ethoxylate (1.2) (Trade name: IGEPAL CA210), Sodium Alkylaryl Ether Sulfate (Trade name: TRITON W-30), Polyethylene glycol 260 mono(hexadecyl/octadecyl) ether and 1-Octadecanol (trade name: Triton RW-75), Octylphenoxypolyethoxy (5)ethanol (Trade name: TRITON X-45), Octylphenoxypolyethoxy(9-10)ethanol (Trade name: TRITON X-100), Polyethylene glycol tert-octylphenyl ether (1,1,3,3-Tetramethylbutyl) phenyl-polyethylene glycol (Trade name: Triton X-114), Octylphenoxypolyethoxy(30)ethanol (Trade Name: TRITON X305), Polydimethylsiloxane methylethoxylate (Trade name: SILWET L7600), Polyethoxylated(20) oleyl alcohol (Trade name: RHODASURF ON-870), Polyethoxylated(35) castor oil (Trade name: Cremophor EL), Polyoxyetheene(20)sorbitan monolaurate (Trade name: TWEEN 20), Polyoxyethelene(20)sorbitan monolaurate (Trade name: TWEEN 21), Polyoxyethe ene(20)sorbitan monolaurate (Trade name: TWEEN(40), Polyoxyethelene(20)sorbitan monolaurate (Trade name: TWEEN 41), Polyoxyethelene(20)sorbitan monolaurate (Trade name: TWEEN 60), Polyoxyethelene(20)sorbitan monolaurate (Trade name: TWEEN 65), Polyoxyethelene(20)sorbitan monooleate (Trade name: TWEEN 80), Polyoxyethelene(20)sorbitan monooleate (Trade name: TWEEN 81), Polyoxyethelene(20)sorbitan monooleate (Trade name: TWEEN 85), Polyoxyethylene(23) dodecyl ether (Trade name: BRIJ 35), Polyoxyethylene(9) lauryl alcohol (Trade name: CHEMAL LA-9), Poly(oxyethylene-co-oxypropylene) block copolymer (Trade name: Pluranic L64), p-[sonomylphenoxypoly(glycidol) (Trade name: SURFACTANT 10 G), Sorbitan Monostearate (Trade name: SPAN 20), Sorbitan Monostearate (Trade name: SPAN 40), Sorbitan Monostearate (Trade name: SPAN 60), Sorbitan Monostearate (Trade name: SPAN 65), Sorbitan Monostearate (Trade name: SPAN 80), or Sorbitan Monostearate (Trade name: SPAN 83). NINATE(tm) and BioTerge(tm) are registered trademarks of Stephen Co. Aerosol(tm) is a registered trademark of American Cyanamide Co. Geropon(tm) and Igepal(tm) are registered trademarks of Rhone-Poulenc, Inc. Pluronic(tm), Tetronic(tm), and Cremophor(tm) are registered trademarks of BASF Corp. Surfynol(tm) is a registered trademark of Air Products and Chemicals Inc. TRITON(tm) and SILWET(tm) are registered trademarks of Union Carbide. TWEEN(tm), BRU(tm), and SPAN(tm) are registered trademarks of ICI Americas, Inc. Zonyl(tm) is a registered trademark of Du Pont Chemicals.

[0037] The osmolarity generated by the osmotic agent should be, between 310 to about 450 mOsm/L. Glucose has been found to be effective. Polyethylene glycol or propylene glycol may be added to optimize the emulsion. Lecithin, a phospholipid that is a constituent of cell membranes, has been shown to be effective as an emulsifier. Because of the limited solubility of lecithin, an additional emulsifier can be added to increase the water holding capacity of the soloution. Tween 80 has been shown to be effective as an additional emulsifier. However, any emulsifier added is effective. Polyethylene glycol (molecular weight 400) in amounts of up to about 1% has been shown to enhance the efficacy.

[0038] In one example, to make the first washing solution, lecithin is dissolved in oil. Additional emulsifiers may be added, The glucose is dissolved in water. The oil/lecithin and water/glucose solutions are mixed with the homogenizer at 100-50,000 rpm for 1 minutes-1 hour or with a colloidal mill. The oil and water ratio is about 6:4.0.1% polyethylene glycol (molecular weight 400) can be added to improve the emulsion. The concentration of glucose should be between 1-10%. Concentrations of from about 1 g to about 10 grams of Lecithin per 100 ml of can be prepared. Tween 80 can be served as an additional emulsifier, its concentration should be between about 0.1 to about 10 grams per 100 ml oil.

[0039] To use the first washing solution, the injured CNS tissue is washed by repeatedly injecting and withdrawing the solution through one or more cannula in subarachnoid spaces as describe above. The washing process can also be accomplished by injecting the solution to one location of subarachnoid spaces and withdrawing the solution from the other location of subarachnoid spaces. After the washing, the solution may stay inside the subarachnoid spaces for certain period of time to allow the solution to absorb water form the brain tissue depending on the patient's condition, then removed partially or as completely as possible and discarded.

[0040] The second washing solution is a pre-emulsified solution which contain one or more emulsifiers in an oil. It can further emulsify the diluted first washing solution inside the subarachnoid space. Although there are many emulsifiers and oil can be chosen. Lecithin and Tween 80 in soybean oil have been effective.

[0041] To make the second solution, lecithin and additional emulsifier(s) are added in an oil and mixed with the homogenizer at 100-50,000 rpm for 1 minutes 1 hour or with a colloidal mill. The lecithin and additional emulsifier(s) can be the same as the first washing, their concentration can be the same or lower.

[0042] To use the second washing solution, similar to the first washing process, the injured CNS tissue is washed by the second washing solution. Discarding part of the emulsified second washing solution and washing again with new washing solution till it becomes clear. The part of the second washing solution stay inside the subarachnoid spaces to maintain the intracranial pressure and to coat the surface of the injured CNS tissue forming a lipid barrier that inhibits the penetration of CSF into the CNS tissues. This provides insulation in case of new CSF coming back. The second wash solution may also be removed completely according to the patient condition. The washing solution may be used to maintain the intracranial pressure. It is advantageous to maintain the intracranial pressure at a low level, preferably at the minimum sustainable level during cases of CNS tissue injuries.

[0043] Because the density of the second washing solution is less than that of the CSF, rotating the body about an axis, or elevating the head, will allow the oil to cover injured CNS tissue surfaces.

[0044] The first or the second washing process alone is effective. The treatment process with first and second washing solution can be repeated if required.

[0045] The treatment effects can be enhanced if CSF production suppressing medications are used. The CSF production suppressing medications may be added to the first or the second washing solution.

[0046] There are many known agents that inhibit production of CSF including diuretics, such as Furosemide (20-200 mg every 4-6 hours), and acetazolamide (0.25-2 g every 4-12 hours). Other agents known to suppress formation of CSF include: beta blocking agents such as isopranolol, and timolol maleate; and calcium channel blockers such as brinzolamide, dorzolamide, methazolamide, sezolamide, lantanoprost, and bis (carbonyl) amidothiadiazole sulfonamides; and carbonic acid anhydrase inhibitors such as triamterene, spironolactone, thiazides, and, Na and K-ATPase inhibitors. This CSF inhibiting agent can be administered intravenously or orally in cases where circulation to the brain has not been impaired, or by direct injection to subarachnoid space, either in combination with the treatment oil, or alone to inhibit new CSF production.

[0047] The treatment effects can be enhanced if the following agents given in a regular route or added to the first or second washing solution. These agents used to treat stroke or other neurological deficiencies including: calcium channel blockers such as Nimodipine, and Flunarizine; calcium chelators, such as DP-b99; potassium channel blockers; Free radical scavengers-Antioxidants such as Ebselen, porphyrin catalytic antioxidant manganese (III) meso-tetrakis (N-ethylpyridinium-2-yl) porphyrin, (MnTE-2-PyP (5+)), disodium 4-[(tert-butylimino) methyl] benzene-1,3-disulfonate N-oxide (NXY-059), Nt-butyl-phenylnitrone or Tirilazad; GABA agonists including Clomethiazole; GABA receptor antagonists, glutamate antagonists, including AMPA antagonists such as GYKI 52466, NBQX, YM90K, YN872, ZK-200775 MPQX, Kainate antagonist SYM 2081, NMDA antagonists, including competitive NMDA antagonists such as CGS 19755 (Selfotel); NMDA channel blockers including Aptiganel (Cerestat), CP-101,606, Dextrorphan, destromethorphan, magnesium, metamine, MK-801, NPS 1506, and Remacemide; Glycine site antagonists including ACEA 1021, and GV 150026; polyamine site antagonists such as Eliprodil, and Ifenprodil; and adenosine receptor antagonists; Growth factors such as Fibroblast Growth Factor (bFGF), Glial cell line derived neurotrophic factor (GDNF), brain derived neurotrophic factor, insulin like growth factor, or neurotrophin; Nitric oxide inhibitors including Lubeluzole; opiod antagonists, such as Naloxone, Nalmefenem, Phosphatidylcholine precursor, Citicoline (CDP-coline); Serotonin agonists including Bay x 3072; Sodium channel blockers such as Fosphenyloin, Lubeluzole, and 619C89; Potassium channel openers such as BMS-204352; anti-inflamatory agents; protein kinase inhibitors, and other agents whose mechanism of action is unknown or uncertain including: Piracetam and albumin; agents that provide energy to cells, such as ATP, co-enzyme A, co-enzyme Q, or cytochrome C.

[0048] The first washing and second washing solution and methods can be combined with existing treatment, such as: recombinant tissue plasminogen activator (rtpA), streptokinase, and tenecteplase in dissolving thrombosis in management of stroke.

EXAMPLE ONE

[0049] Treatment for Spinal Cord Ischemia with Washing Solutions

[0050] The acute spinal cord ischemia was induced in thirty-four rabbits. Group one: control (6 rabbits). Group two: incomplete removal of the CSF. Group three: treatment with washing solutions (6 rabbits).

[0051] Isoflorane was given for anesthesia. A PE-90 tubing was surgically implanted in the cisterna magna for solution out-flow, a PE-10 tubing was implanted to the lumbar thecal sac for solution in-flow in each rabbit. An abdominal incision was made and the aorta was isolated at the level of the renal artery. The aorta was cross-clamped by a clip just caudal to the left (lower) renal artery for one hour to produce spinal cord ischemic injury, then the clip was removed to resume blood supply.

[0052] For group one control, the CSF was not removed.

[0053] For group two, at 15 minutes after ischemia, the CSF was removed as completely as possible (usually 0.8-1.2 ml CSF could be withdrawn), then 0.1 ml CSF was immediately returned. the PE-10 tubing and the PE-90 tubing were closed.

[0054] For group three, at 15 minutes after ischemia, the CSF was removed as completely as possible (usually 0.8-1.2 ml CSF could be withdrawn), then 0.1 ml CSF was immediately returned. Immediately after the 0.1 ml CSF being returned, 5 ml of the first washing solution {component 100 ml of the first washing solution include: 60 ml soybean oil, 40 ml sterile water, 2.8 grams glucose, 0.6% Lecithin, 1.8% Tween 80, 0.05% Polyethylene Glycol (molecular weight 400)} was flushed from the PE-10 in-flow tubing to the PE-90 out-flow tubing, then the final 0.8-1.2 ml of the first washing solution was kept inside the subarachnoid spaces for 5 minutes then was removed as complete as possible. 0.3 ml of the first solution was returned. The 5 ml of the second washing solution (component 100 ml of the second washing solution include: 1 gram Lecithin, 1 gram Tween 80 in 100 ml soybean oil) was flushed from the PE-10 in-flow tubing to the PE-90 out-flow tubing. after the process of second washing solution, the intracranial pressure was maintained at 70 cm H2O with second washing solution druing the ischemia.

[0055] At one week after ischemic injury, the rabbits were tested for behavioral deficit (grade 0: complete recovery; grade 1: able to stand, but unable to walk normally; grade 2: good movement of the hind limbs, but unable to stand; grade 3: spastic paraplegia with slight movement of the hind limbs; grade 4: spastic paraplegia with no movement to the hind limbs).

[0056] The result was summarized as following: At one week after ischemia, in group one and group two, all rabbits showed spastic paraplegia with no movement to the hind limbs (grade 4); In group three, no apparent deficit could be observed, all of rabbits walked and moved smoothly (grade 0).

[0057] Conclusion: a small amount of CSF is toxic enough to cause the spinal cord damage; incomplete removal of the CSF is not effective enough to treat spinal cord ischemia; The wash solutions we invented can provide protection to injured spinal cord.

EXAMPLE TWO

[0058] Treatment for Brain Ischemia with Washing Solutions

[0059] The global cerebral ischemia was induced in twenty rabbits. Group one: control (10 rabbits). Group two: treatment with washing solutions (10 rabbits).

[0060] Isoflorane was given for anesthesia. The trachea was incubated and connected to mechanical intermittent positive-pressure ventilation (tidal volume 30 ml, rate 50/min, O2 concentration 30%). A cannula was surgically positioned in the cisterna magna in each rabbit. A hole of 3 mm in diameter (4 mm lateral to midline and 3 mm posterior to the bregma) was drilled on each side of the skull, a cannula were positioned in the hole on each side through puncture. An arterial line was cannulated through femoral artery for monitoring blood pressure. A femoral vein was also cannulated for withdrawing and infusing blood. Four blood vessels (two common carotid arteries and two vertebrate arteries) were isolated and occluded for one hour with arterial clips to produce ischemia. In order to produce complete global ischemia, 60-120 ml of blood was withdrawn to lower the blood pressure simultaneously. The mean blood pressure was maintained between 30-40 mmHg.

[0061] In group one, at 10 minutes after the global ischemia, 0.8-1.2 ml of CSF was withdrawn from caunnulas in cisterna magna and holes of the skull, then 0.3-0.6 ml of CSF was returned through the these caunnulas. The intracranial pressure was maintained at 70 cm H2O

[0062] In group two, at 10 minutes after the global ischemia, 0.8-1.2 ml of CSF was withdrawn from caunnulas in cistema magna and holes of the skull, then 0.3 ml of CSF was returned through these caunnulas. Immediately after the 0.3 ml CSF being returned, 10 ml of the first washing solution {component 100 ml of the first washing solution include: 70 ml soybean oil, 30 ml sterile water, 1.8 grams glucose, 0.7% Lecithin, 2.1% Tween 80, 0.05% Polyethylene Glycol (molecular weight 400)} was repeatedly injected and withdrawn for three times to wash the brain through caunnulas implanted before the ischemia, then the final 0.8-1.2 ml of the first washing solution is kept inside the subarachnoid spaces for 10 minutes then was removed as complete as possible. 0.5 ml of the first solution was returned. The 10 ml of the second washing solution (component 100 ml of the second washing solution include: 1 gram Lecithin, 1 gram Tween 80 in 100 ml soybean oil) was repeatedly injected and withdrawn for three times as it was done for the first washing solution. After the process of second washing solution, the intracranial pressure was maintained at 70 cm H2O with second washing solution druing the ischemia.

[0063] At one hours of the global ischemia, the arterial clips were removed and then followed by blood infusion. Phenylephrine (10 mg in 100 ml saline) was given to increase and maintain mean blood pressure between 80-100 mmHg. At 24 hours after ischemic injury, the rabbits were tested for behavioral deficit by the following criteria: Maximum Score=400 (meaning brain death or death); Minimum Score=0 (meaning normal brain)

[0064] 1. Level of Consciousness

[0065] 0=complete awareness of auditory stimuli.

[0066] 30=clouded: apparently conscious but drowsy or intermittently irritable on clapping hands and pinching nailbeds of hindlegs.

[0067] 60=stupor: response with movements to pinching nailbed of hindlimb, open eyes, movements may be either purposeful or reflex.

[0068] 100=coma: no movement on painful stimulation (pinching nailbed of hindlimb; should be confirmed on forelimbs as well).

[0069] 2. Respiratory Pattern

[0070] 0=normal rate and rhythm.

[0071] 50=abnormal spontaneous breathing (e.g., periodic gasps, irregular rhythm)

[0072] 75=breathing, but not enough to maintain normal arterial blood gases.

[0073] 100=apnea: complete absence of spontaneous respiratory efforts

[0074] 3. Cranial Nerve Function

[0075] Pupil size: examine in room lighting and record diameters of pupil and iris (R/L)

[0076] 0=normal: 3-7 mm diameter

[0077] 10=abnormal: greater than 7 mm

[0078] 15=severely abnormal: greater than 10, pinpoint, or new anisocoria

[0079] Papillary response to light: use flashlight (R/L)

[0080] 0=normal

[0081] 10=sluggish

[0082] 15=absent

[0083] Eyelid Reflex:

[0084] 0=normal

[0085] 10=sluggish

[0086] 15=absent

[0087] Corneal Reflex: Test with moist cotton swab, observe for eyelid closure (R/L)

[0088] 0=normal

[0089] 10=sluggish

[0090] 15=absent

[0091] Swallow Reflex:

[0092] 0=normal:

[0093] 10=absent

[0094] Auditory-Palpebral (Startle) Reflex: clap hands loudly and observe for motor response

[0095] 0=normal

[0096] 10=no response

[0097] Gag Reflex: stimulate posterior pharynx and observe contraction of the soft palate under direct vision

[0098] 0=normal

[0099] 10=absent

[0100] Carinal Cough Reflex: stimulate carina of trachea with suction catheter and observe cough

[0101] 0=normal

[0102] 10=absent

[0103] 4. Motor and Sensory Function

[0104] Muscle stretch reflex

[0105] 0=normal in all extremities

[0106] 10=increased or absent 1-3 extremities

[0107] 25=absent in all extremities

[0108] Motor Response to Painful Stimulus: Pinch each limb, observe for withdrawal response.

[0109] 0=normal 4

[0110] 10=no response

[0111] 25=coma (no test required)

[0112] Positioning: place rabbit in left lateral decubitus position and observe position assumed.

[0113] 0=normal

[0114] 10=mildly abnormal or intermittent running movements

[0115] 25=markedly abnormal: opistotonus, fixed flexion, total flaccidity, severe running movements

[0116] Muscle Tone: Pick up each extremity and release; observe

[0117] 0=normal

[0118] 10=1 or 2 extremities stiff or flaccid

[0119] 25=3 or 4 extremities stiff or flaccid

[0120] The results are as follow:

[0121] In group one, the score is 400. All rabbits died once disconnected from the ventilator.

[0122] In group two, the average score is from 30-60 (level of consciousness 0-30; respiratory pattern 0; cranial nerve function 0; motor and sensory function 0-30).

[0123] While my above description contains many specifics, these should not be construed as limitations on the scope of the invention, but rather as illustrative examples.

Claims

1. A neuroprotective medicament composition for protecting the central nervous system of a mammal comprising of at least one emulsifier, at least one osmotic agent, water, oil and at least one active ingredient know to treat stroke or other neurological deficiencies selected from the group consisting of calcium channel blockers, potassium channel blockers; free radical scavengers, GABA agonists, GABA receptor antagonists, glutamate antagonists, AMPA antagonists, NMDA antagonists, NMDA channel blockers, Glycine site antagonists, and adenosine receptor antagonists in an emulsion.

2. A neuroprotective medicament composition for protecting the central nervous system of a mammal comprising at least one emulsifier, at least one osmotic agent, water, oil and an active ingredient know to suppress CSF production in an emulsion.

3. A neuroprotective medicament composition for protecting the central nervous system of a mammal according to claim 2 wherein each of said at least one osmotic agents is selected from the group consisting of: glucose, mannitol, glycerin, saccharide, polysaccharide, starch, and protein.

4. A neuroprotective medicament composition according to claim 1 and 2 wherein said oil is selected from the group consisting of hydrocarbon oils from animal, vegetable, and mineral sources, such as soybean oil, mineral oil, cod liver oil, peanut oil, silicone oil, and Vitamin E oil.

5. A neuroprotective medicament composition according to claim 1 and 2 wherein said at least one emulsifier is selected from the group consisting of, phospholipids, phosphoglycerides, sphingomyelin, glycolipids, cholesterol, cholesterol hemisuccinate, sphingolipids, and cerebrosides.

6. A neuroprotective medicament composition according to claim 5 wherein the at least one emulsifier is lecithin and Tween-80.

7. A neuroprotective medicament composition for protecting the central nervous system of a mammal comprising an emulsion solution of at least one osmotic agent, at least one emulsifier, water, and at least 31% oil.

8. A neuroprotective medicament composition for protecting the central nervous system of a mammal consisting of a pre-emulsion solution of at least one emulsifier in oil.

9. A neuroprotective medicament composition according to claim 7 or 8 wherein the oil is selected from the group consisting of hydrocarbon oils from animal, vegetable, and mineral sources, such as soybean oil, mineral oil, cod liver oil, peanut oil, and silicone oil.

10. A neuroprotective medicament composition according to claim 9 wherein the oil is soybean oil.

11. A neuroprotective medicament composition according to claim 7 and 8 wherein each of said at least one emulsifier is selected from the group consisting of, amphipathic lipids or surface active agents such as phospholipids, phosphoglycerides, sphingomyelin, glycolipids, cholesterol, cholesterol hemisuccinate, sphingolipids, and cerebrosides, tween, span, and triton.

12. A neuroprotective medicament composition according to claim 7 and 8 wherein said at least one emulsifier comprises lecithin and Tween 80.

13. A neuroprotective medicament composition according to claim 7 wherein each of said at least one osmotic agent is selected from the following: glucose, mannitol, glycerin, saccharide, polysaccharide, starch, and protein.

14. A neuroprotective medicament composition according to claim 13 wherein said at least one osmotic agent is glucose.

15. A method for protecting Central Nervous System tissue in need of such protection in a mammal, comprising the steps of:

a) Withdrawing a volume of cerebrospinal fluid from the subarachnoid space in spinal canal and or cranium if protection is needed for Central Nervous System tissue,

b) Washing the Central Nervous System tissue by repeatedly injecting and withdrawing or flushing a volume of a neuroprotective medicament composition for protecting the central nervous system of a mammal comprising at least one emulsifier, at least one osmotic agent, water, oil and at least one active ingredient know to treat stroke or other neurological deficiencies selected from the group consisting of calcium channel blockers, potassium channel blockers; free radical scavengers, GABA agonists, GABA receptor antagonists, glutamate antagonists, AMPA antagonists, NMDA antagonists, NMDA channel blockers, Glycine site antagonists, and adenosine receptor antagonists in an emulsion.

16. A method for protecting Central Nervous System tissue in need of such protection in a mammal, comprising the steps of:

a) Withdrawing a volume of cerebrospinal fluid from the subarachnoid space in spinal canal and or cranium if protection is needed for Central Nervous System tissue,

b) Washing the Central Nervous System tissue by repeatedly injecting and withdrawing or flushing a volume of a neuroprotective medicament composition for protecting the central nervous system of a mammal comprising at least one emulsifier, at least one osmotic agent, water, oil and an active ingredient know to suppress CSF production in an emulsion.

17. A method for protecting Central Nervous System tissue in need of such protection in a mammal, comprising the steps of:

a) Withdrawing a volume of cerebrospinal fluid from the subarachnoid space in spinal canal and or cranium if protection is needed for Central Nervous System tissue,

b) Washing the Central Nervous System tissue by repeatedly injecting and withdrawing or flushing a volume of a neuroprotective medicament composition for protecting the central nervous system of a mammal comprising a emulsion solution of at least one osmotic agent, at least one emulsifier, water, and at least 31% oil.

18. A method for protecting Central Nervous System tissue in need of such protection in a mammal, comprising the steps of:

a) Withdrawing a volume of cerebrospinal fluid from the subarachnoid space in spinal canal and or cranium if protection is needed for Central Nervous System tissue,

b) Washing the Central Nervous System tissue by repeatedly injecting and withdrawing or flushing a volume of a neuroprotective medicament composition for protecting the central nervous system of a mammal consisting of a pre-emulsion solution of at least one emulsifier in oil.

19. A method for protecting Central Nervous System tissue in need of such protection in a mammal according to claim 15, 16 or 17, comprising the an added step of:

Washing the Central Nervous System tissue by repeatedly injecting and withdrawing or flushing a volume of a neuroprotective medicament composition for protecting the central nervous system of a mammal consisting of a pre-emulsion solution of at least one emulsifier in oil.

20. A neuroprotective medicament composition for protecting the central nervous system of a mammal according to claim 2 wherein the ingredient know to suppress CSF production is selected from the group consisting of diuretics: including furosemide, acetazolamide, mersalyl, thiaxides, spironolactone, and triamterene.

21. A neuroprotective medicament composition for protecting the central nervous system of a mammal according to claim 2 wherein the ingredient to suppress CSF production is furosemide.

22. A neuroprotective medicament composition for protecting the central nervous system of a mammal according to claim 2 wherein the ingredient to suppress CSF production is acetazolamide.

23. A method for treating stroke in a mammal requiring such treatment comprising:

a) Withdrawing a volume of cerebrospinal fluid from the subarachnoid space in spinal canal and or cranium if protection is needed for Central Nervous System tissue,

b) Washing the Central Nervous System tissue by repeatedly injecting and withdrawing or flushing a volume of a said neuroprotective medicament composition according to claim 1, 2 or claim 7.

c) administering a thrombolytic agent to said mammal in an amount effective to restore blood flow to central nervous system tissue.

24. A method according to claim 23 wherein said thrombolytic agent includes recombinant tissue plasminogen activator (rt-PA).

25. A method for treating a central nervous system injury in a mammal requiring such treatment comprising:

a) Withdrawing a volume of cerebrospinal fluid from the subarachnoid space of the central nervous system of the mammal,

b) Injecting a volume of an intralipid solution into said subarachnoid space.