Lidocaine chemical structure
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Xylocaine

Lidocaine (INN) or lignocaine (former BAN) is a popular local anesthetic and a derivative of cocaine (without its stimulant properties) that is often used in dentistry or topically. The most commonly encountered lidocaine preparations are marketed by AstraZeneca under the brand names Xylocaine and Xylocard, though lidocaine is also found in many other proprietary preparations. more...

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History

Lidocaine, the first amide-type local anesthetic, was developed by Nils Löfgren and Bengt Lundqvist in 1943 and first marketed in 1948.

Also used in pet medications.

Pharmacology

Lidocaine is metabolized in the liver to pharmacologically active breakdown products which are excreted by the kidneys. It is faster acting and longer lasting than procaine (Novocain).

When given intravenously, lidocaine is a class Ib antiarrhythmic agent and will block the sodium channel of the cardiac action potential, which decreases automaticity by reducing the slope of phase 4 depolarization with little effect on the PR interval, QRS complex or QT interval.

This drug is used in the treatment of ventricular cardiac arrhythmias and cardiac arrest with ventricular fibrillation, especially with acute ischemia, though it is not useful in the treatment of atrial arrhythmias.

The elimination half life of intravenous lidocaine is about 109 minutes, but because it is metabolized in the liver (which depends on liver blood flow), dosage should be reduced in patients with low cardiac output or who are in shock. In patients with cardiogenic shock, the half life may exceed ten hours.

Toxicity

Toxicity is most often seen when there has been an inadvertent intravascular injection of lidocaine when being used as a local anesthetic. Central nervous system toxicity manifests as tinnitus, dizziness, paresthesia (pins and needles), confusion and – in more severe cases – seizures or coma. Severe toxicity may also result in cardiovascular system collapse or ventricular fibrillation.

Related Information

  • Benzocaine
  • Bupivacaine
  • Procaine
  • Cocaine


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Management of epistaxis
From American Family Physician, 1/15/05 by Corry J. Kucik

Epistaxis, or nasal bleeding, has been reported to occur in up to 60 percent of the general population. (1-3) The condition has a bimodal distribution, with incidence peaks at ages younger than 10 years and older than 50 years. Epistaxis appears to occur more often in males than in females. (1,4)

Epistaxis is common, and affected persons usually do not seek medical attention, particularly if the bleeding is minor or self-limited. In rare cases, however, massive nasal bleeding can lead to death. (5-7)

Anatomy

The rich vascular supply of the nose originates from the ethmoid branches of the internal carotid arteries and the facial and internal maxillary divisions of the external carotid arteries. (5) Although nasal circulation is complex (Figure 1), epistaxis usually, epistaxis usually is described as either anterior or posterior bleeding. This simple distinction provides a useful basis for management.

Most cases of epistaxis occur in the anterior part of the nose, with the bleeding usually arising from the rich arterial anastomoses of the nasal septum (Kiesselbach's plexus). Posterior epistaxis generally arises from the posterior nasal cavity via branches of the sphenopalatine arteries. (8) Such bleeding usually occurs behind the posterior portion of the middle turbinate or at the posterior superior roof of the nasal cavity.

In most cases, anterior bleeding is clinically obvious. In contrast, posterior bleeding may be asymptomatic or may present insidiously as nausea, hematemesis, anemia, hemoptysis, or melena. Infrequently, larger vessels are involved in posterior epistaxis and can result in sudden, massive bleeding.

Etiology

Most causes of nasal bleeding can be identified readily through a directed history and physical examination. The patient should be asked about the initial presentation of the bleeding, previous bleeding episodes and their treatment, comorbid conditions, and current medications, including over-the-counter medicines and herbal and home remedies. Although the differential diagnosis should include both local and systemic causes (Table 1), (1,5,9) environmental factors such as humidity and allergens also must be considered. (5,10) Often, no cause for the bleeding is identified.

Management

GENERAL APPROACH

Initial management includes compression of the nostrils (application of direct pressure to the septal area) and plugging of the affected nostril with gauze or cotton that has been soaked in a topical decongestant. Direct pressure should be applied continuously for at least five minutes, and for up to 20 minutes. Tilting the head forward prevents blood from pooling in the posterior pharynx, thereby avoiding nausea and airway obstruction. Hemodynamic stability and airway patency should be confirmed. Fluid resuscitation should be initiated if volume depletion is suspected.

Every attempt should be made to locate the source of bleeding that does not respond to simple compression and nasal plugging. The examination should be performed in a well-lighted room, with the patient seated and clothing protected by a sheet or gown. The physician should wear gloves and other appropriate protective equipment (e.g., surgical mask, safety glasses). A headlamp or head mirror and a nasal speculum should be used for optimal visualization.

An epistaxis tray can be created using common supplies and a few specialized instruments (Figure 2). Clots and foreign bodies in the anterior nasal cavity can be removed with a small (Frazier) suction tip, irrigation, forceps, and cotton-tipped applicators.

[FIGURE 2 OMITTED]

When posterior bleeding is suspected, the general location of the source should be determined. This step is important because different arteries supply the floor and roof of the posterior nasal cavity; therefore, selective ligation may be required. (5,11)

Diffuse oozing, multiple bleeding sites, or recurrent bleeding may indicate a systemic process such as hypertension, anticoagulation, or coagulopathy. In such cases, a hematologic evaluation should be performed. Appropriate tests include a complete blood count, anticoagulant levels, a prothrombin time, a partial thromboplastin time, a platelet count and, if indicated, blood typing and crossmatching. (9,12)

Although most patients with epistaxis can be treat-ed as outpatients, hospital admission and close observation should be considered for elderly patients and patients with posterior bleeding or coagulopathy. Admission also may be prudent for patients with complicating comorbid conditions such as coronary artery disease, severe hypertension, or significant anemia.

ANTERIOR EPISTAXIS

If a single anterior bleeding site is found, vasoconstriction should be attempted with topical application of a 4 percent cocaine solution or an oxymetazoline or phenylephrine solution. For bleeding that is likely to require more aggressive treatment, a local anesthetic, such as a 4 percent cocaine solution or tetracaine or lidocaine (Xylocaine) solution, should be used. Adequate anesthesia should be obtained before treatment proceeds.

Intravenous access should be obtained in difficult cases, especially when anxiolytic medications are to be used.

Cotton pledgets soaked in vasoconstrictor and anesthetic should be placed in the anterior nasal cavity, and direct pressure should be applied at both sides of the nose for at least five minutes. Then the pledgets can be removed for reinspection of the bleeding site. If this measure is unsuccessful, chemical cautery can be attempted using a silver nitrate stick applied directly to the bleeding site for approximately 30 seconds. (5) Other treatment options include hemostatic packing with absorbable gelatin foam (Gelfoam) or oxidized cellulose (Surgicel). Use of desmopressin spray (DDAVP) may be considered in a patient with a known bleeding disorder. (5,13)

Larger vessels generally respond more readily to electrocautery. However, electrocautery must be performed cautiously to avoid excessive destruction of healthy surrounding tissues. Note that use of electrocautery on both sides of the septum may increase the risk of septal perforation. (9) Interestingly, at least one study (14) found no difference in efficacy or complication rate between chemical cautery (silver nitrate stick) and electrocautery.

If local treatments fail to stop anterior bleeding, the anterior nasal cavity should be packed, from posterior to anterior, with ribbon gauze impregnated with petroleum jelly or polymyxin B-bacitracin zinc-neomycin (Neosporin) ointment. Nonadherent gauze impregnated with petroleum jelly and 3 percent bismuth tribromophenate (Xeroform) also works well for this purpose. (5,9) Bayonet forceps and a nasal speculum are used to approximate the accordion-folded layers of the gauze, which should extend as far back into the nose as possible. Each layer should be pressed down firmly before the next layer is inserted (Figure 3). Once the cavity has been packed as completely as possible, a gauze "drip pad" may be taped over the nostrils and changed periodically.

Alternatively, a preformed nasal tampon (Merocel or Doyle sponge) may be used. (12) The tampon is inserted carefully along the floor of the nasal cavity, where it expands on contact with blood or other liquid. Application of lubricant jelly to the tip of the tampon facilitates placement. After the nasal tampon has been inserted, wetting it with a small amount of topical vasoconstrictor may hasten effectiveness. It may be necessary to drip saline into the nostril to achieve full expansion of the tampon if the bleeding has decreased at the time of insertion. Although one study (15) found no significant difference in patient comfort or efficacy with nasal tampons or ribbon gauze packing, simplicity of placement makes the tampons highly useful in primary care settings. When applied in the outpatient setting, nasal packing may be left in place for three to five days to ensure formation of an adequate clot. (12)

Complications of nasal packing procedures include septal hematomas and abscesses from traumatic packing, sinusitis, neurogenic syncope during packing, and pressure necrosis secondary to excessively tight packing. Because of the possibility of toxic shock syndrome with prolonged nasal packing, use of a topical antistaphylococcal antibiotic ointment on the packing materials has been recommended. (10,12)

POSTERIOR EPISTAXIS

Posterior bleeding is much less common than anterior bleeding (16) and usually is treated by an otolaryngologist. Posterior packing may be accomplished by passing a catheter through one nostril (or both nostrils), through the nasopharynx, and out the mouth (Figure 4). A gauze pack then is secured to the end of the catheter and positioned in the posterior nasopharynx by pulling back on the catheter until the pack is seated in the posterior choana, sealing the posterior nasal passage and applying pressure to the site of the posterior bleeding. (5) Although this procedure is not outside the scope of family practice, it requires special training and usually is performed by an otolaryngologist.

Various balloon systems are effective for managing posterior bleeding and are less complicated than the packing procedure. The double-balloon device (Figure 2) is passed into the affected nostril under topical anesthesia until it reaches the nasopharynx. The posterior balloon then is inflated with 7 to 10 mL of saline, and the catheter extending out of the nostril is withdrawn carefully so that the balloon seats in the posterior nasal cavity to tamponade the bleeding source. Next, the anterior balloon is inflated with roughly 15 to 30 mL of saline in the anterior nasal cavity to prevent retrograde travel of the posterior balloon and subsequent airway obstruction. An umbilical clamp or other device can be placed across the stalk of the balloon adjacent to the nostril to further prevent dislodgement; the clamp should be padded to prevent pressure necrosis of the nasal skin. Balloon packs generally are left in place for two to five days. As with anterior packing, tissue necrosis can occur if a posterior pack is inserted improperly or balloons are overinflated.

If a specialized balloon device is not available, a Foley catheter (10 to 14 French) with a 30-mL balloon may be used. The catheter is inserted through the bleeding nostril and visualized in the oropharynx before inflation of the balloon. (18) The balloon then is inflated with approximately 10 mL of saline, and the catheter is withdrawn gently through the nostril, pulling the balloon up and forward. The balloon should seat in the posterior nasal cavity and tamponade a posterior bleed. With traction maintained on the catheter, the anterior nasal cavity then is packed as previously described. Traction is maintained by placing an umbilical clamp on the catheter beyond the nostrils, which should be padded to prevent soft tissue damage. As with anterior epistaxis, topical antistaphylococcal antibiotic ointment may be used to prevent toxic shock syndrome. However, use of oral or intravenous antibiotics for posterior nasal packing most likely is unnecessary. (19)

PERSISTENT BLEEDING

Patients with anterior or posterior bleeding that continues despite packing or balloon procedures may require treatment by an otolaryngologist. Endoscopy may be used to locate the exact site of bleeding for direct cauterization.

Hot water irrigation, a technique described more than 100 years ago, has been reexamined recently. This technique has shown promise in reducing discomfort and length of hospitalization in patients with posterior epistaxis. (20,21) More invasive alternatives include arterial ligation and angiographic arterial embolization.

REFERENCES

(1.) Pollice PA, Yoder MG. Epistaxis: a retrospective review of hospitalized patients. Otolaryngol Head Neck Surg 1997;117:49-53.

(2.) Petruson B. Epistaxis. A clinical study with special reference to fibrinolysis. Acta Otolaryngol Suppl 1974;317:1-73.

(3.) Schaitkin B, Strauss M, Houck JR. Epistaxis: medical versus surgical therapy: a comparison of efficacy, complications, and economic considerations. Laryngoscope 1987;97:1392-6.

(4.) Rubin Grandis J, et al. The management of epistaxis. 3d ed. Alexandria, Va.: American Academy of Otolaryngology-Head and Neck Surgery Foundation, 1999.

(5.) Tan LK, Calhoun KH. Epistaxis. Med Clin North Am 1999;83:43-56.

(6.) Cassisi NJ, Biller HF, Ogura JH. Changes in arterial oxygen tension and pulmonary mechanics with the use of posterior packing in epistaxis: a preliminary report. Laryngoscope 1971;81:1261-6.

(7.) Lucente FE. Thanatology: a study of 100 deaths. Trans Am Acad Ophthalmol Otolaryngol 1972;76:334-9.

(8.) Koh E, Frazzini VI, Kagetsu NJ. Epistaxis: vascular anatomy, origins, and endovascular treatment. AJR Am J Roentgenol 2000;174:845-51.

(9.) Pond F, Sizeland A. Epistaxis. Strategies for management. Aust Fam Physician 2000;29:933-8.

(10.) Smith JA. Nasal emergencies and sinusitis. In: Tintinalli JE, Ruiz E, Krome RL, eds. Emergency medicine: a comprehensive study guide. 4th ed. New York: McGrawHill, Health Professions Division, 1996:1082-93.

(11.) Adornato SG. Epistaxis: new approach [Letter]. Otolaryngol Head Neck Surg 2000;123:524.

(12.) Frazee TA, Hauser MS. Nonsurgical management of epistaxis. J Oral Maxillofac Surg 2000;58:419-24.

(13.) Lethagen S, Ragnarson Tennvall G. Self-treatment with desmopressin intranasal spray in patients with bleeding disorders: effect on bleeding symptoms and socioeconomic factors. Ann Hematol 1993;66:257-60.

(14.) Toner JG, Walby AP. Comparison of electro and chemical cautery in the treatment of anterior epistaxis. J Laryngol Otol 1990;104:617-8.

(15.) Corbridge RJ, Djazaeri B, Hellier WP, Hadley J. A prospective randomized controlled trial comparing the use of Merocel nasal tampons and BIPP in the control of acute epistaxis. Clin Otolaryngol 1995;20:305-7.

(16.) Viducich RA, Blanda MP, Gerson LW. Posterior epistaxis: clinical features and acute complications. Ann Emerg Med 1995;25:592-6.

(17.) McFerran DJ, Edmonds SE. The use of balloon catheters in the treatment of epistaxis. J Laryngol Otol 1993;107:197-200.

(18.) Williams M, Onslow J. Airway difficulties associated with severe epistaxis. Anaesthesia 1999;54:812-3.

(19.) Derkay CS, Hirsch BE, Johnson JT, Wagner RL. Posterior nasal packing. Are intravenous antibiotics really necessary? Arch Otolaryngol Head Neck Surg 1989;115:439-41.

(20.) Stangerup SE, Dommerby H, Lau T. Hot-water irrigation as a treatment of posterior epistaxis. Rhinology 1996;34:18-20.

(21.) Stangerup SE, Dommerby J, Siim C, Kemp L, Stage J. New modification of hot-water irrigation in the treatment of posterior epistaxis. Arch Otolaryngol Head Neck Surg 1999;125:686-90.

CORRY J. KUCIK, LT, MC, USN, is a naval flight surgeon and hyperbaric medical officer with Marine Fighter Attack Squadron 251, Marine Corps Air Station, Beaufort, S.C. Dr. Kucik received his medical degree from the Uniformed Services University of the Health Sciences F. Edward Hebert School of Medicine, Bethesda, Md., and completed a family medicine internship at Naval Hospital Jacksonville, Jacksonville, Fla.

TIMOTHY CLENNEY, CDR, MC, USN, is a staff family physician at Naval Hospital, Jacksonville, as well as a naval undersea medical officer. After graduating from the University of South Florida College of Medicine, Tampa, Dr. Clenney completed a family medicine residency at Naval Hospital Jacksonville. He also completed a faculty development fellowship and earned a master of public health degree from Emory University, Atlanta.

Address correspondence to Timothy Clenney, CDR, MC, USN, 1705 Broad Water Ct., Orange Park, FL 32003 (e-mail: tclenney@msn.com. Reprints are not available from the authors.

The authors indicate they do not have any conflicts of interest. Sources of funding: none reported.

The opinions and assertions contained herein are the private views of the authors and are not to be construed as official or as reflecting the views of the U.S. Navy Medical Department or the U.S. Naval Service at large.

The authors thank James R. Phelan, CDR, MC, USN, head of otorhinolaryngology at the Naval Aerospace Medical Institute, Pensacola, Fla., for guidance and review of the manuscript.

Members of various family practice departments develop articles for "Practical Therapeutics." This article is one in a series coordinated by the Department of Family Medicine at Naval Hospital, Jacksonville, Fla. Guest editor of the series is Anthony J. Viera, LCDR, MC, USNR.

COPYRIGHT 2005 American Academy of Family Physicians
COPYRIGHT 2005 Gale Group

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