Anesthesiology Update, Perioperative Use Of Intravenous Lidocaine

The current article is an update in the field of anesthesiology, adopted from the clinical findings published in the renowned journal “Anesthesiology”. A number of studies and meta-analyses have indicated that perioperative lidocaine infusion is effective in decreasing postoperative pain and improve other outcomes. The authors of this article have reported the findings relevant for the practicing anesthesiologist when using lidocaine infusion in different clinical settings.

Surgery affects both pro- and anti-inflammatory systems in the body. Anti-inflammatory components tend to contribute to infections, whereas pro-inflammatory components are involved in post-operative complication and sometimes leading to organ failure. However, some of these complications can be alleviated by perioperative lidocaine infusion. Many studies have reported the benefits of perioperative lidocaine infusion with respect to reduction in pain, nausea, ileus duration, opioid requirement, and length of hospital stay. The benefits have been observed with infusion rates of IV lidocaine which mimics plasma lidocaine concentrations obtained during epidural administration.

This article provides an overview of the findings in the context relevant for practicing anesthesiologist in different clinical settings as discussed below.

Abdominal Surgery

Following are some of the observations made when perioperative lidocaine was administered in patients undergoing open or laparoscopic abdominal surgery.

• Lidocaine infusion in doses ranging from 1.5 to 3 mg ∙ kg−1 ∙ h−1 (after a bolus of 0 to 1.5 mg/kg), has shown to improve postoperative pain scores in patients undergoing open or laparoscopic abdominal surgery.
• Opioid requirements in the post-anesthesia care unit were reduced by an average of 4.2mg morphine equivalents. Total analgesic consumption has been reduced by 35% when lidocaine continued for 0 to 1h postoperatively.
• During colorectal surgery, lidocaine infusion was as effective as epidural administration of local anesthetics with respect to pain scores, opioid consumption, and other outcomes.
• In bariatric surgery patients, lidocaine infusion reduced opioid consumption which improved recovery scores.
• Lidocaine Infusion shortened the duration of postoperative ileus by an average of 8 hours and decreases the incidence of postoperative nausea and vomiting by 10 to 20%
• Toxicity from perioperative lidocaine infusion (e.g. neurologic changes—lightheadedness, dizziness and visual disturbances, and cardiac dysrhythmias) is very rare.

Perioperative lidocaine infusion may be an effective alternative for patients whom neuraxial analgesia is contraindicated.

Breast Surgery

Studies noted no difference between perioperative lidocaine infusion compared to placebo infusion, on total morphine consumption, pain scores, duration of hospital stay, postoperative nausea and vomiting (PONV), a return of bowel function, and patient satisfaction in the immediate postoperative period. However, some studies have shown that lidocaine infusion has reduced incidence of chronic postsurgical pain at 3 and 6 months after mastectomy

Gynecologic And Obstetric Surgery

No difference was observed between lidocaine and placebo in the primary outcomes (length of the hospital stay or 6-min walk) or secondary outcomes (pain scores, opioid consumption, PONV, recovery, and fatigue scores in patients undergoing a total abdominal hysterectomy. Hence these studies do not support the use of perioperative lidocaine infusion for the patient undergoing total abdominal hysterectomy.

In obstetrics, the inclusion of lidocaine did not affect the Apgar score or acid base status, suggesting that the infusion may reduce the maternal stress due to surgery without ill effects on neonates. However, additional studies are warranted in this regard.

Cardiothoracic Surgery

Studies have not shown any difference in a postoperative pain or in opioid or benzodiazepines consumption after coronary artery bypass grafting (CABG) in patients who received lidocaine infusion (at 1.5 mg/kg bolus followed by an infusion rate of 30μg / kg∙ min until 48 h postoperatively). As the lidocaine was not added to the cardiopulmonary bypass pump volume, effective doses may not have been achieved during bypass. The available evidence does not support the use of perioperative lidocaine infusion for cardiac surgery patients.

Spine Surgery

Perioperative lidocaine infusion was found to reduce pain scores and was non-inferior to postoperative opioid consumption in major spine surgery patients. Also, postoperatively (at 1 and 3 months after surgery, patients reported improved quality of life in the survey. Based on the short- and long- term benefits, perioperative lidocaine infusion may provide value for patients undergoing major spine surgery.

Perioperative lidocaine infusion is indeed beneficial but in some surgical procedures. So far, no mechanism can provide the explanation for the differences in the outcomes between relatively similar procedures. One of the reasons can be differences in the study design, sample size, infusion rate etc.

In short, perioperative lidocaine infusion may be useful adjunct analgesic in enhanced recovery protocols.

Reference

Dunn, Lauren K., and Marcel E. Durieux. "Perioperative Use of Intravenous Lidocaine" The Journal of the American Society of Anesthesiologists 126.4 (2017): 729-737'.