Anesthesia catheter

Baboons were surgically prepared with chronically indwelling silastic catheters implanted in either femoral or jugular veins under pentobarbital or halothane anesthesia using methods described in detail by Lukas et al. 

A large-diameter multihole urethral catheter should be inserted to facilitate saline lavage and evacuation of blood clots. Surgical removal of blood clots under anesthesia may be required if saline lavage is ineffective. Active bleeding from isolated areas may be cauterized with an electrode or laser. In severe cases that are unresponsive to local or systemic pharmacologic intervention,... 

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. 

The primary site of action of epidurally administered agents is on the spinal nerve roots. As with spinal anesthesia, the choice of drug to be used is determined primarily by the duration of anesthesia desired. However, when a catheter has been placed, short-acting drugs can be administered repeatedly. Bupivacaine is typically used when a long duration of surgical block is needed. Lidocaine is used most often for intermediate length procedures chloroprocaine is used when only a very short duration of anesthesia is required. 

Neuraxial anesthesia and postoperative indwelling epidural catheter use Spinal or epidural hematomas, which may result in long-term or permanent paralysis, can occur with the use of anticoagulants and neuraxial (spinal/epidural) anesthesia or spinal puncture. The risk of these events may be higher with postoperative use of indwelling epidural catheters or concomitant use of other drugs affecting hemostasis, such as NSAIDs. 

May be introduced directly into a particular segment of the bronchopulmonary tree by inserting (under local anesthesia and direct vision) a plastic catheter into the trachea. Instill 2 to 5 mL of the 20% solution by a syringe connected to the catheter. 

Increased risk of spinal/epidural hematomas with neuraxial anesthesia or spinal puncture. Risk is further increased by use of indwelling spinal catheters, repeated/ traumatic epidural/spinal puncture, or use of drugs affecting hemostasis (NSAIDs, anticoagulants, platelet inhibitors). 

Administration of local anesthetics via iontophoresis can also be used to produce topical anesthesia prior to certain dermatologic procedures. For example, lidocaine iontophoresis can adequately anesthetize a small patch of skin for performing a minor surgical procedure (placement of an intravenous catheter, laser treatment of port-wine stains, and so forth).18,50,66 Ion-tophoretic application of local anesthetics offers... 

Finally, therapists may work with patients who are receiving central neural blockade in the form of an epidural or spinal injection. These procedures are common during natural and caesarean childbirth and in some other surgical procedures. Administration of local anesthetics into the spaces around the spinal cord are also used to treat individuals with severe and chronic pain—that is, patients recovering from extensive surgery, patients who have cancer, or patients with other types of intractable pain. In these situations, therapists may notice that an indwelling catheter has been placed in the patient s epidural or subarachnoid space to allow repeated or sustained administration of the spinal anesthesia. 

The surgical placement of vascular catheters and the instillation of bacteria, either intratracheally or intraperitoneally, require general anesthesia. Anesthesia is induced with a combination of ketamine and xylazine and maintained with additional doses of ketamine as needed. During the surgical procedure the rabbit breathes spontaneously through an endotracheal tube (3.0 mm ID, 4.2 mm OD, Kendall/Sheridan, Argyle, NY). 

A 24-gauge catheter (Angiocath, Becton-Dickinson, Sandy, UT) is placed in the marginal ear vein for induction and maintenance of anesthesia. 

Normal Wistar rat kidneys are fully perfused with physiologic saline through a catheter placed in the aorta. Renal cortical tissue is removed, homogenized and diluted with physiological saline at about 20% suspension. Two ml of renal cortical homogenate are emulsified with an equal volume of Freund s complete adjuvant. This emulsion is injected subcutaneously into rabbits twice a month for two months. Seven days after the last injection, the rabbits are bled from the carotid artery under anesthesia. The sera are decomple-mented for 30 min at 56 °C and absorbed with freshly harvested rat erythrocytes. 

The rats are fasted for about 4 h and are anesthetized with 80 mg/kg bw Ketamin plus 5 mg/kg Midazolam administered intravenously into the tail vein via an indwelling venous catheter. The amount corresponds to a volume of about 0.3 mL. Anesthesia is monitored by checking the reflexes and is maintained by repeat dosing of ketamine/midazolam. 

When properly performed this method can be very effective in rupturing Hasner s membrane. In cases resistant to the massage technique, the clinician may attempt forceful lacrimal irrigation, probing with a flexible lacrimal probe, balloon catheter dilation, or silicone intubation. These procedures, especially the latter two, are done under general anesthesia and are typically considered only after the child reaches at least 3 to 4 months of... 

Latex is present in many medical devices, including surgical and examination gloves, catheters, intubation tubes, anesthesia masks, and dental fillers. Reported allergic reactions range from contact urticaria to anaphylaxis (1). 

A 48-year-old obese woman had a 22G interscalene catheter inserted under local anesthesia via a short-bevel stimulating needle. Anesthesia was achieved using 0.6% ropivacaine 40 ml followed by an infusion of ropivacaine 0.2% for effective analgesia. On day 3, she reported blurred vision and a painful neck swelling. She had developed a hematoma around the catheter insertion site (confirmed by ultrasound) and had an ipsilateral Homer s syndrome including myosis, ptosis, enophthalmos, ipsUateral anhidrosis, and conjunctival hyperemia. 

The accidental transformation of epidural to subarachnoid block can be dramatic, and tracheal intubation and ventilatory support may be necessary (102). Severe hypotension can result after inadvertent intrathecal local anesthesia (SEDA-21, 131). In women in labor, fetal bradycardia can occur. Postdural puncture headache can also be a sign of catheter migration. 

A 68-year-old man developed total spinal anesthesia after the administration of 20 ml of ropivacaine 1% without a prior test dose via an epidural catheter, which was inadvertently placed intrathecally (83). Initial aspiration of both the Touhy needle and the catheter failed to identify the intrathecal position of the catheter. The patient noted weakness in his right leg immediately after the end of the injection. This was followed by weakness in his right arm, asystole, apnea, and loss of consciousness. Ventricular escape beats were noted and sinus rhythm returned after mask ventilation with 100% oxygen and the administration of atropine 1 mg and ephedrine 50 mg. He was able to open his eyes, but remained apneic and was therefore intubated and ventilated. Cardiovascular stabihty was maintained with incremental boluses of ephedrine to a total of 60 mg. He regained consciousness and was successfully extubated 145 minutes later. AH sensory and motor deficits had resolved within 8 hours and no neurological deficit or transient neurological symptoms were detected 5 days later. 

Horner s syndrome (miosis, ptosis, anhidrosis, and vasodilatation, with increased temperature of the affected side) can result from epidural anesthesia. A report of Horner s syndrome due to a thoracic epidural catheter has highlighted the fact that small doses of local anesthetic can block the sympathetic fibers to the face, particularly when the catheter tip is close to T2 (142). The same symptoms have been reported after obstetric epidural anesthesia (143). 

The possibility of increased maternal mortality is a topic of debate. In 1979 there were 150 maternal deaths (0.27 per 1000 births) in Germany, of which 15-25% were apparently related to regional anesthesia, with such complications as hypotension, systemic toxicity, total spinal block, hematoma, catheter rupture, and uterine injury (SED-12, 253) (154). However, obstetric regional... 

Holst D, Mollmaim M, Karmaim S, Wendt M. Kreislaufverhalten unter Spmalanasthesie. Kathetertechnik versus Smgle-dose-Verfahren. [Circulatory reactions under spmal anesthesia. The catheter techmque versus the single dose procedure.] Anaesthesist 1997 46(1) 38 2. 

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