LidocaineLidocaine, the first amino amide-type local anesthetic, was first synthesized under the name Xylocaine by Swedish chemist Nils Löfgren in 1943.
Indications Rapid acting local anesthetic for procedures ranging from infiltration to regional nerve block Antiarrhythmic in the treatment of vent. arrhythmias Treatment of status epilepticus (INVESTIGATIONAL) Treatment of pain Operative Neuropathic pain
Pharmacology Half life: 90-120 min. Time to steady state: 8-10 hours Distribution: Lipo-philic, widely distributed into body Protein binding: 60-80 % Metabolism: 90% metabolite in the liver, 10 % unchanged drug excreted by kidney. Mao & Chen, 2000
PharmacologyActive metabolites: Active metabolites: 90% in the liver monoethylglycinexylidide(MEDX), half life 2 hrs, 60-80% as potent as lidocaine glycinexylidine(GX), half life 10 hrs Half-life of lidocaine is approximately 90–120 min. hepatic impairment (average 343 min.) or Congestive heart failure (average 136 min.)
Mechanism of action:Intravenous lidocaine is analgesic, antihyperalgesic, and antiinflammatory.These properties are mediated by a variety of mechanisms, including sodium channel blockade,as well as inhibition of G protein–coupled receptors and N-methyl-D-aspartate receptors. * *In sub-anesthetic dose, it blocks spontaneous ectopic discharge of the injured nerve without blocking normal nerve conduction** * Acta Anaesthesiol Scand.2006 * * Int Anesthesiol Clin. 2003 * Mao & Chen, 2000
Contraindications for the use of lidocaine • Heart block, second or third degree (without pacemaker) • Severe sinoatrial block (without pacemaker) • Serious adverse drug reaction to amide local anaesthetics • Concurrent treatment with quinidine, flecainide, disopyramide, procainamide (Class I agents) • Prior use of Amiodarone hydrochloride • Hypotension not due to Arrhythmia • Bradycardia • Accelerated idioventricular rhythm • Pacemaker • Porphyria, especially acute porphyria (AIP);
Sodium Channel• The sodium channel is a voltage gated channel (Nav) is grouped into 9 classifications dependant upon there location and action.• The therapeutic goal would be to develop one that could specifically block the four channels (1.3, 1.7, 1.8 and 1.9) that have been shown to be in use for the proliferation of neuropathic and other pain signals.
Sodium Channels role in neuropathic pain A Theory suggests that the fast activation, inactivation and rapid re-priming kinetics and persistent current component of The sodium channel 1.3 contribute to the development of spontaneous ectopic discharges and sustained firing characteristics of injured sensory nerves, leading to neuropatheic pain. Rogers M, et al.2006
Its mode of action is the attenuation of peripheral nociceptors sensitisation and CNS hyperexcitability, it achieves this by stablaising the open state of the sodium channel, this will lead to the sodium channel effectively being deactivated. Rogers M, et al., Semin Cell Dev Biol (2006)
Lidocaine Bartlett et al. 1961 First study suggesting there is a role for systemic lidocaine for relief of post-op pain Boas et al. 1982 Clinical role for lidocaine for treatment of peripheral and central pain
Inhibition of Postoperative Pain by Continuous Low- Dose intravenous Infusion of Lidocaine Jean Cassuto, Anesthesia and Analgesia low-dose continuous infusion of lidocaine is devoid of side effects and can be used to decrease the severity of postoperative pain, thus reducing the need for potent morphinomimetic drugs in the postoperative period
Treatment of Postoperative Paralytic ileus by Intravenous Lidocaine Infusion Gunnar Rimback, Md, Anesth Analg,1990 lidocaine or saline placebo. Thirty patients scheduled for elective cholecystectomy were studiedContinuous IV infusion of lidocaine during the first postoperative day after cholecystectomy can reduce the need for narcotics and shorten the period of postoperative colonic inhibition in patients undergoing major abdominal surgery.Secondary to the inhibition of peritoneal irritation followed by reduced activation of inhibitory gastrointestinal reflexes.
Intravenous Lidocaine Infusion Facilitates Acute Rehabilitation after Laparoscopic Colectomy Abdourahamane Kaba, M.D.,*Anesthesiology 2007 45 patients enrolledConclusions: Intravenous lidocaine improves postoperative analgesia, fatigue, and bowel function after laparoscopic colectomy. These benefits are associated with a significant reduction in hospital stay.
Perioperative Intravenous Lidocaine Has Preventive Effects on Postoperative Pain and Morphine Consumption After Major Abdominal Surgery Wolfgang Koppert, Germany ,Anesth Analg 2004 A prospective, randomized, and double-blinded study of 40 patients undergoing major abdominal surgeryThe perioperative administration of systemic lidocaine is most effective in surgery associated with the development of pronounced central hyperalgesia, i.e., intestinal and bowel surgery.The pain experience after these types of surgery can be attenuated by lidocaine in a clinically relevant manner.
Intravenous Lidocaine for Ambulatory Anesthesia Christopher L. Wu, MD ,Inter Anes Research Society,Dec. 2009Using 1.5–3 mg kg h lidocaine significantly reduced the incidence of nausea and vomiting (32% vs 52%), Marginally reduced pain scores , Decreased duration of postoperative ileus (8.4 h) and hospital stay (0.84 days).
Systemic Lidocaine Shortens Length of Hospital Stay After Colorectal Surgery A Double-blinded, Randomized, Placebo-controlled Trial Susanne Herroeder, MD Annals of Surgery, August 200760 patients of ASA physical status I to III, between 18 and 75 years of age, scheduled for elective colorectal surgery
Study Drug AdministrationPatients in the lidocaine group received 1.5 mg/kglidocaine intravenously as a loading dose before induction of general anesthesia.Immediately after tracheal intubation, a continuous systemic lidocaine infusion (2 mg/min) was initiated and terminated 4 hours after skin closure.Patients in the control group were treated likewise using NaCl 0.9% in a double-blinded fashion.
Outcome Measures The primary outcome measure • length of hospital stay. Secondary outcome measures • Length of PACU stay, • Time until return of bowel function, • Postoperative pain and opioid consumption, • Plasma levels of several pro- and anti- inflammatory interleukins .
Conclusions:Systemic lidocaine may thus provide a convenient and inexpensive approach to improve outcome for patients not suitable for epidural anesthesia.
Comparison of the effects of thoracic epiduralanalgesia and i.v. infusion with lidocaine on cytokine response, postoperative pain and bowel function in patients undergoing colonic surgery C. P. Kuo ,British Journal of Anaesthesia Sept, 2006Conclusions The TEA lidocaine had better pain relief, lower opioid consumption, earlier return of bowel function and lesser production of cytokines than IV lidocaine during 72 h after colonic surgery; IV group was better than the control group.
Systemic administration of local anesthetics to relieve neuropathic pain : a systemic review and meta-analysis Tremont-Lukats, 2005
conclude“Lidocaine and mexiletine produced no major adverse events in controlled clinical trials, were superior to placebo to relieve neuropathic pain, and were as effective as other analgesics used for this condition.” Tremont-Lukats, 2005
The Analgesic Response to IntravenousLidocaine in the Treatment of Neuropathic Pain F. Michael Ferrante, Anesth A nalg 199613 patients were enrolled in the study,with neuropathic pain for at least 6 months .Lidocaine was administered IV at a rate of 8.35 mg/min over 60 min.In conclusion, the results of this study suggest that the analgesic response to IV lidocaine is best characterized by a precipitous ‘break in pain” over a narrow dosage and concentration range.
Topical Lidocaine Patch Relieves a Variety of Neuropathic Pain Conditions Devers, Clinical Journal of Pain: Sept 2000Results:Moderate or better pain relief was reported by 13 of the 16 participants (81%).Patients had a mean duration of patch use of 6.2 weeks with continued relief.
Chronic pain treatment with intravenous lidocaine Petersen P, Neurol Res., Sep,1986 18 patients with severe chronic pain states due neurological diseases. After the infusion of lidocaine 14 patients (78%) had significant pain relief ranging from 2 hours to 25 days.
Efficacy of 5-Day Infusion Continuous Lidocaine for the Treatment of Refractory C R P S Robert . schwartzman, md,pain medicine, 2009The majority of patients demonstrated a significant decrease in pain parameters and other symptoms and signs of CRPS. The pain reduction lasted an average of 3 months.Lidocaine may be particularly effective for thermal and mechanical allodynia. Less clinically significant effects were documented on the motor aspects of the syndrome.
Diabetic Polyneuropathy (DPN) Viola et al., Journal of Diabetes and Complications, 2006 15 pat. with intractable painful DPN Double-blind, placebo-controlled crossover trial Two doses: 5mg/kg and 7.5mg/kg vs. saline Infusion during 4h and every 4 weeks Both doses ↓↓ severity of pain Dose-response effect ! Reduction present at 14 and 28 days after Decrease in qualitative nature of pain up to 28d
Guidelines Pre infusion assessment and preperation Lidocaine test Lidocaine infusion Home infusion
Pre infusion assessment Complete history and physical examination Quantitative pain assessment Any history of allergy from lidocaine Any history of Heart or liver diseases ECG Ferrini& Paice, 2004
Patient preperation Patients are required to have nothing by mouth for 4 hours prior to the procedures Written consent Vital signs are monitored including heart rhythm, heart rate, blood pressure and oxygen saturation
Lidocaine test Dose: 1-3 mg/kg (average 100 mg) Concentration: 8 mg/ml IV over 20-30 min. OR 40 mg/ml SC over 30-60 min (2-3 ml/hr) Monitor pain relief, vital signs and side effects q15 min. 50% of the dose in elderly patients >70 year, patients with heart or liver disease Ferrini& Paice, 2004
Lidocaine infusion If pain relief > 50% and no side effects Dose 0.5 -2 mg/kg/hr IV OR SC Monitor pain, V/S and side effect after 15 min then 60 min then q 8 hr then prn Titrate up based on pain relief If any side effects occurred, stop infusion, reassess after 30-60 min then resume with 20% Or last safe dose
Home infusion Patient must have a stable caregiver situation, with 24-hour supervision by a competent adult Patient must consent to being visited by a registered nurse 2–7 times a week Patient/caregiver should be provided with a lidocaine patient information sheet
Home Massages• Lidocaine infusion is safe and effective intervention for operative and chronic pain• Lidocaine infusion has narrow therapeutic index. So, it needs clear guidelines to demonstrate how we use it safely