Anesthesia injectable

Regional nerve block anesthesia— injection of a small amount of local anesthetic into the tissue immediately surrounding a nerve supplying the region to be anesthetized... 

Intravenous regional anesthesia—injection of local anesthetic into a suitable vein supplying the limb to be anesthetized the blood flow from this limb is then restricted by a tourniquet... 

Epidural anesthesia—injection of local anesthetic into the space external to the dural sac that encloses the spinal cord, enabling nerves to the pelvis to be selectively anesthetized during obstetrical labor and delivery... 

Spinal anesthesia Injection of local anesthetic into the cerebrospinal fluid in the lumbar space. In most adults, the spinal cord terminates above the second lumbar vertebra. Therefore, in this region there is a relatively large space to accommodate injected drug. Various specific gravity preparations can be used to manage the height up the spinal cord that the drug will travel... 

The onset of action is fast (within 60 seconds) for the intravenous anesthetic agents and somewhat slower for inhalation and local anesthetics. The induction time for inhalation agents is a function of the equiUbrium estabUshed between the alveolar concentration relative to the inspired concentration of the gas. Onset of anesthesia can be enhanced by increasing the inspired concentration to approximately twice the desired alveolar concentration, then reducing the concentration once induction is achieved (3). The onset of local anesthetic action is influenced by the site, route, dosage (volume and concentration), and pH at the injection site. 

Another injectable anesthetic widely used in feline and primate practice is ketamine hydrochloride [1867-66-9]. Ketamine, a derivative of phencychdine, can be chemically classified as a cyclohexamine and pharmacologically as a dissociative agent. Analgesia is produced along with a state that resembles anesthesia but in humans has been associated with hallucinations and confusion. For these reasons, ketamine is often combined with a tranquilizer. The product is safe when used in accordance with label directions, but the recovery period may be as long as 12—24 h. 

Injection shock, bronchospasm during anesthesia, cardiac standstill and arrhythmias Inhalation acute bronchial asthma, emphysema, bronchitis, bronchiectasis... 

Injection shock 2 mcg/mL diluted solution IV bronchospasm during anesthesia ... 

Topical anesfliesia involves die application of die anes-flietic to die surface of the skin, open area, or mucous membrane The anesthetic may be applied wifli a cotton swab or sprayed on the area This type of anesthesia may be used to desensitize the skin or mucous membrane to the injection of a deeper local anesthetic. In some instances, topical anesthetics may be applied by the nurse ... 

Local infiltration anesthesia is die injection of a local anesthetic druginto tissues. This type of anesfliesia may be used for dental procedures, die suturing of small wounds, or making an incision into a small area, such as that required for removing a superficial piece of tissue for biopsy. 

Regional anesthesia is the injection of a local anesthetic around nerves so that the area supplied by these nerves will not send pain signals to the brain. The anesthetized area is usually larger than the area affected by... 

Spinal anesthesia is a type of regional anesthesia that involves the injection of a local anesthetic drug into the subarachnoid space of die spinal cord, usually at the level of the second lumbar vertebra There is a loss of feeling (anesdiesia) and movement in the lower extremities, lower abdomen, and perineum. 

A conduction block is a type of regional anesthesia produced by injection of a local anesthetic drug into or near a nerve trunk. Examples of a conduction block include an epidural block (injection of a local anesthetic into the space surrounding the dura of the spinal cord) a trails sacral (caudal) block (injection of a local anesthetic into the epidural space at the level of the sacrococcygeal notch) and brachial plexus block (injection of a local anesdietic into the brachial plexus). Epidural, especially, and trailssacral blocks are often used in obstetrics. A brachial plexus block may be used for surgery of the arm or hand. 

For recreational use, ketamine is often snorted or smoked with marijuana or tobacco products, but it may also be injected intramuscularly (Weiner et al. 2000). The typical street dose of ketamine ranges from 30 to 300 mg. These amounts are in contrast to the chnical doses used for anesthesia, which range from 2 to 10 mg/kg. Ketamine has a half-life of less than 2 hours and is metabohzed by the cytochrome P450 en2yme system (Koesters et al. 2002 Reich and SUvay 1989). 

Tsilibary and Wissig, 1977 Bettendorf, 1979). Abnormal respiration (as a result of anesthesia) affects the retention time of intraperitoneally injected particles. Anesthesia which stimulates respiration results in a decrease of retention time while respirationsuppressing anesthesia results in the opposite effect (Courtice and Simmonds, 1954). 

In rabbits under light amytal anesthesia, chlordan has no direcr effect on the blood pressure, but produces a type of respiration having many characteristics in common with Cheyne-Stokes type. The generalized tremors, opisthotonus, tonic and clonic convulsions, produced by chlordan were decreased or abolished and respiration restored to normal by suitable injections of the sodium salts of amytal, phenobarbital, and pentothal. The LD60 of chlordan, which was about 20 mg. per kg. on intravenous administration to intact rabbits, was increased to about 60 mg. per kg. through the antidotal action of the barbiturates. An unidentified chlorine-containing degradation product with acidic properties was recovered from the urine of rabbits treated with chlordan. Approximately one third of its chlorine content was set free on hydrolysis at 100° C. with sodium hydroxide in either absolute alcohol or in water. 

Injecting a local form of anesthetic into the cerebrospinal fluid surrounding the spinal cord causes spinal anesthesia. This injection is made below the level of the second lumbar vertebra in order to minimize direct nerve trauma. Spinal anesthesia is... 

Epidural anesthesia is administered by injecting local anesthetic into the epidural space. Located outside the spinal cord on its dorsal surface, the epidural space contains fat and is highly vascular. Therefore, this form of anesthesia can be performed safely at any level of the spinal cord. Furthermore, a catheter may be placed into the epidural space, allowing for continuous infusions or repeated bolus administrations of anesthetic. 

An important difference between epidural anesthesia and spinal anesthesia is that agents injected into the epidural space may readily enter the blood due to the presence of a rich venous plexus... 

Similar to Voltaren" Emulgel, oily droplets of an eutectic mixture of lidocaine and prilocaine are dispersed in a hydrogel to provide local anesthesia to the skin for injections and siugical treatment (Emla cream). A further possibility is the dermal administration of a liposome dispersion as a spray (Heparin PUR ratiopharm Spriih-gel "). After administration, water and isopropylic alcohol evaporate partially resulting in an increase of concentration and in a transition from the initial liposome dispersion into a lamellar liquid crystal [32]. The therapeutic effect appears to be influenced favorably by the presence of lecithins rather than by the degree of liposome dispersion. 

Forms of local anesthesia. Local anesthetics are applied via different routes, including infiltration of the tissue (infiltration anesthesia] or injection next to the nerve branch carrying fibers from the region to be anesthetized (conduction anesthesia of the nerve, spinal anesthesia of segmental dorsal roots), or by application to the surface of the skin or mucosa (surface anesthesia]. In each case, the local anesthetic drug is required to diffuse to the nerves concerned from a depot placed in the tissue or on the skin. 

Injectable anesthetics (p. 220) are frequently employed for induction. Intravenous injection and rapid onset of action are clearly more agreeable to the patient than is breathing a stupefying gas. The effect of most injectable anesthetics is limited to a few minutes. This allows brief procedures to be carried out or to prepare the patient for inhalational anesthesia (intubation). Administration of the volatile anesthetic must then be titrated in such a manner as to counterbalance the waning effect of the injectable agent. 

Increasing use is now being made of injectable, instead of inhalational, anesthetics during prolonged combined anesthesia (total intravenous anesthesia—TIVA). 

TIVA has become feasible thanks to the introduction of agents with a suitably short duration of action, including the injectable anesthetics propofol and etomidate, the analgesics alfentanil und remifentanil, and the muscle relaxant mivacurium. These drugs are eliminated within minutes after being adminster-ed, irrespective of the duration of anesthesia. 

Ketamine has analgesic activity that persists beyond the period of unconsciousness up to 1 h after injection. On regaining consciousness, the patient may experience a disconnection between outside reality and inner mental state (dissociative anesthesia). Frequently there is memory loss for the duration of the recovery period however, adults in particular complain about dis-Ltillmann, Color Atlas of Pharmacology... 

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