Effect of Lidocaine and Epinephrine on Staphylococcus aureus in a Guinea Pig Model of Surgical Wound Infection

Abstract

Postoperative wound infection, most often with, is of ubiquitous concern in surgical practice, occurring in an average of 1.5 to 5 percent of all procedures. The antimicrobial properties of local anesthetics have been documented over the past 25 years by in vitro studies. This study evaluates the effects of lidocaine preparations on in an in vivo setting. In a wound infection model using live albino guinea pigs, inoculum was introduced for the reproducible bacterial colonization of clean surgical wounds. One of two sites on the dorsum of each animal was infiltrated with a commercial lidocaine preparation (with and without epinephrine) prior to inoculation with (10 cfu/ml). The other site, inoculated with without preinfiltration with lidocaine, served as the control. Cultures from the sites treated with lidocaine were then compared with cultures from the control sites. All control sites had a consistent presence >or=10 cfu/ml, the threshold for bacterial inhibition of wound healing. Infiltration of the wound with 2 ml of 2% lidocaine prior to inoculation was associated with an average decrease in bacterial count of >70 percent ( n= 19). On the other hand, the addition of epinephrine (1:100,000) to lidocaine was associated with a 20-fold in bacterial counts compared with control values ( n= 10). This is the first study to demonstrate inhibition of by a local anesthetic agent in an in vivo model of a surgical wound. This information suggests a possible role for local anesthetics in prophylaxis against surgical wound infection.

Comparison of continuous local anaesthetic and systemic pain treatment after axillary lymphadenectomy in breast carcinoma patients – a prospective randomized study

“…The rates of inflammation or hematomas were not higher after the use of local anaesthetics compared to the placebo or standard analgesia treatment groups 2,5,9,13,15,24–26,28,29,33,34. On the contrary, local anaesthetics seem to reduce the occurrence of inflammation 35,36,37. Like other authors, we also did not notice any toxic side effects of local anaesthetics.…”

Prevention of Surgical Site Infections and Biofilms: Pharmacokinetics of Subcutaneous Cefazolin and Metronidazole in a Tumescent Lidocaine Solution

“…69–72 The lidocaine in a TAAD solution may act synergistically with TAAD antibiotics to kill bacteria. Antibacterial effects of lidocaine have been attributed to disruption of microbial cell membrane permeability by transmembrane anion (Na + , K + , Ca ++ ) channel blockade.…”

Infected animal models for tissue engineering

“…Attention to detail in surgical protocol design is necessary. Seemingly minor decisions can alter infection in an animal model- for example, the choice of local anesthetic can impact the course of infection [12]. External drugs may need to be delivered to create metabolic imbalances [13] or immune suppression [14, 15].…”