Intraspinal injections

Some types of injections must be made iso-osmotic with blood serum. This applies particularly to large-volume intravenous infusions if at all possible hypotonic solutions cause lysis of red blood corpuscles and thus must not be used for this purpose. Conversely, hypertonic solutions can be employed these induce shrinkage, but not lysis, of red cells which recover their shape later. Intraspinal injections must also be isotonic, and to reduce pain at the site of injection so should intramuscular and subcutaneous injections. Adjustment to isotonicity can be determined by the following methods. 

Contraindications Hypersensitivity to methylene blue or any component of its formulation, glucose-6-phosphatedehydrogenase (G6PD) deficiency, intraspinal injection, severe renal insufficiency, treatment of methemoglobinemia in cyanide poisoning... 

Dosages and routes of administration Levomethadone can be given by mouth or by intravenous, intramuscular, subcutaneous or intraspinal injection. For pain treatment, intravenous doses are between 2.5 and 5 mg and oral doses between 5 and 10 mg. For maintenance treatment in addicts, much higher oral doses up to more than 100 mg are used. 

Glucocorticoids given intrathecally can cause a rise in cerebrospinal fluid protein and carry the risk of arachnoiditis (SED-8, 820). Chemical meningitis has been reported after two intrathecal injections of methylpredni-solone acetate (450) and after lumbar facet joint block (SEDA-17, 450). Intraspinal injections of hydrocortisone for multiple sclerosis apparently led in one case to a cauda equina syndrome, with subsequent ulceromutilating acro-pathy (SEDA-17, 450). Intra-discal injections of triamcinolone acetonide in a number of French cases led to disk or epidural calcification, sometimes symptomless (SEDA-17, 450). 

Water-soluble preparations should be avoided for intraspinal injections of glucocorticoids as they may cause severe chemical meningitis of short duration (133 ). 

Viral vaccines present problems of safety testing far more complex than those experienced with bacterial vaccines. With killed viral vaccines the potential hazards are those due to incomplete virus inactivation and the consequent presence of residual live virus in the preparation. The tests used to detect such live virus consist of the inoculation of susceptible tissue cultures and of susceptible animals. The cultures are examined for cytopathic effects and the animals for symptoms of disease and histological evidence of infection at autopsy. This test is of particular importance in inactivated poliomyelitis vaccine, the vaccine being injected intraspinally into monkeys. At autopsy, sections of brain and spinal cord are examined microscopically for the histological lesions indicative of proliferating poliovirus. 

Opioids maybe administered in a variety of routes including oral (tablet and liquid), sublingual, rectal, transdermal, transmucosal, intravenous, subcutaneous, and intraspinal. While the oral and transdermal routes are most common, the method of administration is based on patient needs (severity of pain) and characteristics (swallowing difficulty and preference). Oral opioids have an onset of effect of 45 minutes, so intravenous or subcutaneous administration maybe preferred if more rapid relief is desired. Intramuscular injections are not recommended because of pain at the injection site and wide fluctuations in drug absorption and peak plasma concentrations achieved. More invasive routes of administration such as PCA and intraspinal (epidural and intrathecal) are primarily used postoperatively, but may also be used in refractory chronic pain situations. PCA delivers a self-administered dose via an infusion pump with a preprogrammed dose, minimum dosing interval, and maximum hourly dose. Morphine, fentanyl, and hydromorphone are commonly administered via PCA pumps by the intravenous route, but less frequently by the subcutaneous or epidural route. 

McNeill KG, Molla MA, Harrison JE. 1973. Distribution of thorium series nuclides in beagles after intraspinal Thorotrast injection. Health Phys 24 403-409. 

Some of the dosage formulations available for protein pharmaceuticals are listed in Table 5.7. An examination of Table 5.7 reveals that no protein drug up until this time has been formulated for oral administration. Most protein drugs are administered by means of injection (parenteral administration). Parenteral administration includes intravenous, intra-arterial, intracardiac, intraspinal or intrathecal, intramuscular, intrasynovial, intracuta-neous or intradermal, subcutaneous injections, and injection directly into a dermal lesion (e.g., a wart). The parenteral route of administration requires a much higher standard of purity and sterility than oral administration. It also may require trained... 

Medico-technical instruments such as infusion pumps can be used in PCA (patient-controlled analgesia, Fig. 1) to provide patient-orientated and therapy as required, e.g. with morphine injection solutions. Depending on the patients perception of pain, they may add small doses of analgesics to the basic infusion by means of an electrically controlled infusion pump. The physician specifies the basic dose, which is infused independent of patient demands, the boluses that can be demanded, an hourly maximum dose and a refractory time that cannot be reduced between two doses. The infusion may be given intravenously, subcutaneously, epidurally or intraspinally. 

Epidural A form of intraspinal analgesia where the agent is injected into the epidural space that surrounds the dura mater, which is the membrane that contains the cerebo-spinal fluid directly outside the spinal cord. 

Intrathecal A form of intraspinal anaesthesia or analgesia in which the agent is injected through the dura mater and arachnoid membrane into the cerebro-spinal fluid which surrounds the spinal cord. 

Drugs can also be given by injection. Methods of injection include subcutaneous, intramuscular, intravenous, intra-arterial, intra-articular, intraspinal and epidural. 

Intraspinal and epidural injections are given under certain circumstances to have a local effect, either as anaesthesia or to treat infection of the central nervous system. For... 

Pruritus is a common and potentially disabling complication of opioid use. It can be caused by intraspinal or systemic injections of opioids, but it appears to be more intense after intraspinal administration. The effect appears to be mediated largely by dorsal horn neurons and is reversed by naloxone. 

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