Lidocaine-epinephrine Solution Research Articles

Topical Anaesthesia in Flexible Nasofibrolaryngoscopy

IntroductionThe emergence of flexible nasofibrolaryngoscopy in recent decades has facilitated the development of Otolaryngology and the nasofibrolaryngoscope has become an essential diagnostic tool for the otolaryngologist. However, its use is not without discomfort for the patient, which is why various options for topical anaesthesia have been proposed during the development of the technique. Materials and methodsThis was a prospective, double blind, crossover study in patients with no history of nasal disease, through which we compared the use of topical anaesthetic (Lidocaine)+epinephrine, oxymetazoline and placebo. Using a visual analogue scale, the degree of discomfort was assessed during each scan. ResultsWe evaluated 18 patients, 10 women (55.6%) and 8 men (44.4%), with a mean age of 28±4 years. The degree of disturbance generated by the scan with the application of lidocaine–epinephrine was 1.94; with oxymetazoline it was 3.78, and with placebo, 4.61. When the lidocaine–epinephrine solution was compared with oxymetazoline, there was a statistical significance in favour of lidocaine–epinephrine (P<.05). When we compared the use of lidocaine–epinephrine with the placebo, the result was also statistically significant in favour of lidocaine–epinephrine (P<.05). ConclusionsIn this study we demonstrated that using lidocaine associated with epinephrine as a topical anaesthetic prior to flexible nasofibrolaryngoscopy decreases pain and feeling of discomfort for the patient. Consequently, we can recommend the use of topical nasal anaesthesia when performing this exploration.

Anestesia tópica en la nasofibrolaringoscopia flexible

IntroductionThe emergence of flexible nasofibrolaryngoscopy in recent decades has facilitated the development of Otolaryngology and the nasofibrolaryngoscope has become an essential diagnostic tool for the otolaryngologist. However, its use is not without discomfort for the patient, which is why various options for topical anaesthesia have been proposed during the development of the technique. Material and methodsThis was a prospective, double blind, crossover study in patients with no history of nasal disease, through which we compared the use of topical anaesthetic (Lidocaine) + epinephrine, oxymetazoline and placebo. Using a visual analogue scale, the degree of discomfort was assessed during each scan. ResultsWe evaluated 18 patients, 10 women (55.6%) and 8 men (44.4%), with a mean age of 28±4 years. The degree of disturbance generated by the scan with the application of lidocaine-epinephrine was 1.94; with oxymetazoline it was 3.78, and with placebo, 4.61. When the lidocaine-epinephrine solution was compared with oxymetazoline, there was a statistical significance in favour of lidocaine-epinephrine (P<0.05). When we compared the use of lidocaine-epinephrine with the placebo, the result was also statistically significant in favour of lidocaine-epinephrine (P<0.05). ConclusionsIn this study we demonstrated that using lidocaine associated with epinephrine as a topical anaesthetic prior to flexible nasofibrolaryngoscopy decreases pain and feeling of discomfort for the patient. Consequently, we can recommend the use of topical nasal anaesthesia when performing this exploration.

Is Clonidine an Adequate Alternative to Epinephrine as a Vasoconstrictor in Patients With Hypertension?

To evaluate the safety and efficacy of an admixture of lidocaine with clonidine with regard to the anesthetic abilities, hemodynamic parameters, and postoperative pain control and to compare the results with those obtained with a lidocaine-epinephrine solution. A total of 50 patients with poorly controlled, moderate hypertension (American Society of Anesthesiologists class II) who presented for uncomplicated upper third molar extraction were included in a double-blind study. The time of onset of action, duration, and intensity of anesthesia and the vasoconstrictor properties were evaluated. The hemodynamic changes (ie, systolic blood pressure, diastolic blood pressure, mean arterial pressure, heart rate, ST-segment depression of 1 mm or greater, and cardiac arrhythmias) were recorded. The presence of postoperative pain and analgesic requirements were also compared. The results were analyzed using an unpaired, type sample equal-variance t test with the Bonferroni correction. Of the 50 patients with hypertension (American Society of Anesthesiologists class II), 25 received 2 mL of 2% lidocaine with clonidine (15 μg/mL) and 25 received lidocaine with epinephrine (12.5 μg/mL). There were no significant differences between the 2 agents with regard to the time of onset of action, duration or intensity of anesthesia, or the vasoconstrictor properties. The clonidine group showed better hemodynamic parameters compared with the epinephrine group. The clonidine group showed significantly lesser postoperative pain and, therefore, had lesser analgesic consumption. Clonidine could be a useful and safe alternative to epinephrine for intraoral block anesthesia with lidocaine in patients with hypertension and American Society of Anesthesiologists class II.

CARDIOVASCULAR EFFECTS OF INTRAOSSEOUS INJECTIONS OF 2 PERCENT LIDOCAINE WITH 1:100,000 EPINEPHRINE AND 3 PERCENT MEPIVACAINE

Because a number of patients have reported an increase in heart rate with the intraosseous, or i.o., injection, it is important to evaluate changes in the cardiovascular system with this injection technique. The purpose of this study was to determine the cardiovascular effects of an i.o. injection of 2 percent lidocaine with 1:100,000 epinephrine and 3 percent mepivacaine. With the use of a repeated-measures design, the authors randomly assigned 42 subjects to receive i.o. injections of 1.8 milliliters of 2 percent lidocaine with 1:100,000 epinephrine or 1.8 mL of 3 percent mepivacaine in a double-blinded manner at two appointments. At each appointment the authors monitored electrocardiographic findings, cardiac rate, systolic and diastolic blood pressure, and mean arterial pressure before, during and after administration of anesthetic solutions. With the 2 percent lidocaine with 1:100,000 epinephrine solution, 28 (67 percent) of 42 subjects experienced an increase in heart rate that might be attributed to the effect of the epinephrine. In 22 (79 percent) of these subjects, the heart rate returned to within 5 beats of baseline values within four minutes after solution deposition. The authors found no significant increase in heart rate in subjects receiving the 3 percent mepivacaine. No significant differences (P > .05) were found in mean diastolic, mean systolic or mean arterial blood pressure values between the subjects receiving 2 percent lidocaine with 1:100,000 epinephrine and those receiving 3 percent mepivacaine. The majority of subjects receiving the i.o. injection of the 2 percent lidocaine-epinephrine solution experienced a transient increase in heart rate. No significant increase in heart rate was seen with the i.o. injection of 3 percent mepivacaine. While patients would likely notice the heart rate increase with the lidocaine-epinephrine solution, it would not be clinically significant in most healthy patients. In patients whose medical condition, drug therapies or epinephrine sensitivity suggests caution, 3 percent mepivacaine is a good alternative for i.o. injections.

Modified technique of iontophoretic anesthesia for myringotomy in children.

A modified technique is described for iontophoretic anesthesia in children who require myringotomy and insertion of a tube (tympanostomy). Principal modifications include the following procedures: (1) preoperative parenteral sedation; (2) relatively painless injection of lidocaine hydrochloride-epinephrine hydrochloride solution into the external auditory canal skin after iontophoresis alone to eliminate the extreme bony canal wall tenderness; (3) injection of lidocaine-epinephrine solution into an atelectatic middle ear to anesthetize the promontory for painless tube insertion; (4) substitution of a disposable ECG electrode for a metal plate electrode to eliminate the possibility of electrical burn from metal-to-skin contact. These modifications enhance the effectiveness and the safety of iontophoretic anesthesia, minimize the need for general anesthesia, and liberalize the indications for tympanostomy.

Circulatory Effects of Peridural Block

The influence of epinephrine on the cardiovascular effects of high (T5) peridural analgesia was studied in 19 human volunteers, each of whom received two injections. In 12, the effects of lidocaine alone were compared with those of lidocaine–epinephrine. Peridural analgesia with lidocaine alone produced small (5 to 10 per cent) changes in cardiac output (CO), total peripheral resistance (TPR) and mean arterial pressure (MAP). During peridural analgesia with Iidocaine–epinephrine a 49 per cent increase in CO and a 37 per cent decrease in TPR resulted in a 10 per cent decrease in MAP. All of these changes from control were statistically significant and were significantly greater than those produced by lidocaine alone. In another seven subjects, the effects of peridural injection of lidocaine–epinephrine were compared with those of injection of saline–epinephrine. The two solutions produced similar effects on the heart, but lidocaine–epinephrine solution caused a significantly greater decrease in TPR, and consequently in MAP, and a greater increase in leg blood flow than did saline–epinephrine solution.

THE TOXIC EFFECT OF A NEW LOCAL ANAESTHETIC OF ANILIDE TYPE (L 67) ON THE TISSUES.

The tissue irritating effect of a new local anaesthetic of anilide type (L67) in rat was judged from the tensile strength of healing wounds in tissue infiltrated with 0.5 ml of the solution.A 2% L 67 solution decreased the tensile strength by about 40% and a 3% L 67 solution by 56.7%.When a 2% L 67 solution and a 2% lidocaine solution were used the result showed that the lidocaine solution decreased the tensile strength by 21.8% compared to the L 67 solution.A comparison between a 2% lidocaine-epinephrine solution and a 3% L 67 solution with epinephrine 3.33% μg/ml showed that the tensile strength decreased with 31.6% in wounds inflicted in tissues infiltrated with 2% lidocaine-epinephrine solution. A comparison between L 67 and mepivacaine showed practically no difference in their effect on the tensile strength of the wounds.