Spinal administration route

The availability of new routes of administration have led to increased utility and decreased opioid adverse drug reaction risk. Epidural and intrathecal administration through spinal catheters produces adequate regional analgesia at relatively low total doses compared with intravenous or oral routes. As such, spinal administration can thus minimize somnolence, nausea, vomiting, and respiratory depression associated with these medications. Other alternative routes include intranasal administration of butorphanol, and rectal and transdermal administration of fentanyl [28]. Availability of such options provides not only a decreased risk of adverse reactions, but also more comfortable measures for patients who would otherwise require continued intravenous administration, or for those who are unable to receive oral medication [28,29]. 

Intrathecal Management of severe spasticity of spinal cord origin in patients who are unresponsive to oral baclofen therapy or experience intolerable CNS side effects at effective doses. Intended for use by the intrathecal route in single bolus test doses (via spinal catheter or lumbar puncture) and, for chronic use, only in implantable pumps approved by the FDA specifically for the administration of baclofen into the intrathecal space. 

Opioid analgesics can also be used at low doses by the epidural and spinal routes of administration to produce excellent postoperative analgesia. 

As indicated in Table 2.1, drugs may be injected into veins, muscles, subcutaneous tissue, arteries, or into the subarachnoid space of the spinal canal (intrathecal). For obvious reasons, intraarterial and intrathecal injections are reserved for specialized drug administration requirements, such as regional perfusion of a tumor with a toxic drug or induction of spinal anesthesia, respectively. Therefore, the more routine injection routes are intravenous (IV), intramuscular (IM), and subcutaneous (SC). Because these three modalities involve skin puncture, they carry the risks of infection, pain, and local irritation. 

The more novel routes of administration of opioids, including oral, nasal, rectal, transdermal, spinal, and by patient-controlled methods, have been outlined (SEDA-17, 78). Oral transmucosal fentanyl administration, avoiding first-pass metabolism, produces analgesia and sedation in both adults and children undergoing short, painful outpatient procedures. The quality of analgesia is good, and the adverse effects are those typical of the opioids. 

Compared with conventional routes, spinal opioid administration carries potentially greater morbidity and can only be justified if it produces equal or superior pain relief compared with conventional methods, with fewer unwanted effects (SED-11, 139). 

Many injections are formulated as aqueous solutions, with Water for Injections as the vehicle. Their formulation depends upon several factors including the aqueous solubility of the active ingredient, the dose, its thermal stability, the route of administration, and whether the product is to be offered as a multiple-dose product (i.e. with doses removed on different occasions) or as a single-dose form (as the term suggests, only one dose per container). Most injections are prepared as a single-dose form but this is mandatory for certain routes, e.g. spinal injections where the intrathecal route is used, and large volume intravenous infusions. Multiple-dose... 

RNase (RNAse ribonuclease) An enzyme that cleaves RNA. routes of administration of drugs There are many different routes but common ones include intravascular injection or infusion (into the blood vessels, e.g. by drip, mainly intravenous (into veins) but sometimes intra-arterial (into arteries) intramuscular (injection into muscles) subcutaneous (injection beneath the dermis of the skin) intradermal (injection into the skin) transdermal (across the skin. e.g. from skin patches) topical (application to the skin or mucous membranes) per rectum (by an ointment or suppository into the rectum) intravaginally (by an ointment or pessary into the vagina) intrathecal (by injection into the subarachnoid space of the spinal cord) intranasally (often as a spray) orally (by mouth) inhalation. rRNA ribosomal RNA. 

Effective in the management of severe postoperative, chronic, or cancer pain. Spinal opioids can be administered by a single bolus injection into the epidural or subarachnoid space or by continuous infusion via an indwelling catheter. Dosage requirement by these routes is significantly less than with IV administration (epidural opioid doses 10-fold lower than IV doses intrathecal opioid doses 100-fold lower than IV doses). Morphine, hydromorphone, fentanyl, and sufentanil are effective when administered intrathecally. The most commonly used local anesthetic in continuous epidural infusions is bupivacaine. Fentanyl, morphine, or hydromorphone is usually combined with bupivacaine for epidural infusions. 

The formulation of parenteral products involves careful consideration of the proposed route of administration and the volume of the injection. Injections are administered to the body by many routes into various layers of the skin, the subcutaneous and muscle tissue, into arteries or veins, into or around the spinal cord, or directly into various organs (e.g., the heart or the eye). The volume to be injected can range from microliters, typically diagnostic agents administered intradermally or insulin administered subcutaneously, to several liters administered intravenously as infusions. The route of administration and the volume to be injected affect the composition of the formulation. 

As stated earlier, the drug is affected by esterases and since the spinal-fluid virtually contains little or no esterase therefore, when given by this route of administration it remains active till such time it gradually gets absorbed into the general circulation. 

A lumbar puncture was carried out successfully and samples of cerebro spinal fluid taken for analysis. Dr Mitchell then read out aloud the name of the patient, the drug and the dose from the label on the first syringe and then handed it to Dr North. Dr Mitchell did not, however, read out the route of administration. Dr North, having received the syringe, now asked if the drug was Cytosine, which Dr Mitchell confirmed. Dr North then removed the cap at the bottom of the syringe and screwed it onto the spinal needle after which he injected the contents of the syringe. 

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