Effects of levobupivacaine on wound healing

Evaluation of primary wound healing and potential complications after perioperative infiltration with lidocaine without adrenaline in surgical incisions in dogs and cats

BACKGROUND

Pre-emptive local analgesia with the use of lidocaine is practised increasingly in veterinary medicine as part of applied multimodal analgesia, despite its controversial impact on wound healing. The purpose of this prospective, randomised, double-blinded, placebo-controlled clinical study was to evaluate if preoperative subcutaneous infiltration of lidocaine has a negative impact on primary wound healing of surgical incisions. Fifty-two companion animals (3 cats and 49 dogs) were enrolled in the study. The inclusion criteria were as follows: American Society of Anaesthesiologists (ASA) score I or II, a minimum body weight of 5 kg, and a planned incisional length of at least 4 cm. Surgical incisions were infiltrated subcutaneously with lidocaine without adrenaline or NaCl (placebo). Follow-up questionnaires for owners and veterinarians and thermography of the surgical wound were used to assess wound healing. Antimicrobial use was documented.

RESULTS

There was no significant difference in either the total score or the individual assessment points between the treatment and the placebo group on the owner or the veterinary questionnaires in regard to primary wound healing (P > 0.05 for all comparisons). No significant difference was found between the thermography results of the treatment and placebo group (P = 0.78), and there was no significant correlation between the total score from the veterinary protocol and thermography results (Spearman's correlation coefficient - 0.10, P = 0.51). Surgical site infections developed in 5/53 (9.4%) surgeries and its occurrence varied significantly between the treatment and the placebo group as all cases of infection were in the placebo group (P = 0.05).

CONCLUSION

The results of this study indicate that lidocaine used as a local anaesthetic did not affect wound healing in patients with ASA scores I-II. The results suggest that lidocaine infiltration in surgical incisions can be safely used to reduce pain.

Outcomes following single, caudally based bilateral versus unilateral frontonasal sinusotomy for treatment of equine paranasal sinus disease

Background

Bilateral sinus disease is relatively uncommon in horses, accounting for 3%–4.5% of horses with sinonasal disease, but may require bilateral paranasal surgery for complete resolution. Complications and recurrence following bilateral sinusotomy have not been reported or compared to those following unilateral procedures.

Objective

To describe clinical features and outcomes in horses undergoing standing single, caudally based bilateral frontonasal sinusotomy compared to unilateral frontonasal surgery.

Methods

Records of horses (n = 37) undergoing surgical treatment for sinus disease (five bilateral, 32 unilateral) were retrospectively reviewed (2010–2017) for signalment, presenting complaint, duration of signs preoperatively, diagnostic imaging, treatments administered, duration hospitalization, complications, and owner satisfaction with the procedure. Mann–Whitney testing was used to compare age, duration of hospitalization, and follow‐up time in horses undergoing unilateral or bilateral procedures. Fisher's exact testing was used to determine if sex predilection was present for unilateral or bilateral disease. Survival time and time to recurrence were compared by Kaplan–Meier survival curves and log‐rank curve comparison testing. Significance was assessed at p < 0.05.

Results

Length of signs prior to admission did not differ between horses with unilateral and bilateral disease (p = 0.09), but there was a tendency for horses with bilateral disease to have clinical signs for longer. Age (p = 0.19) and hospitalization duration (p = 0.53) did not differ between horses undergoing unilateral versus bilateral procedures. Recurrence or failure to resolve signs was reported in 11/32 (34%) of unilateral and 0/5 bilateral cases (p = 0.07).

Conclusions

The bilateral single, caudally based sinusotomy approach may be considered to effectively treat bilateral paranasal sinus disease without concern for increased risk of life‐threatening complications or longer hospitalization duration than would be typical for unilateral sinusotomy procedures.

Topical application of lidocaine or bupivacaine in the healing of surgical wounds in dogs

Purpose:

To analyze the anesthetic drugs interference with wound healing when used in the surgical bed.

Methods:

Macro and microscopic aspects of healing of surgical wounds were evaluated after instillation of topical anesthetics without vasoconstrictor or saline solution 0.9% as control in the transsurgical period. Thirty dogs, males and females were divided into two experimental groups. In both groups, two circular punch lesions of 6 mm diameter were performed in the abdomen. In group 1, lidocaine was instilled in one of the lesions and saline solution in the contralateral lesion. In group 2 the procedure was repeated with the use of bupivacaine. The macroscopic assessment of the lesions was performed on the first, third and tenth postoperative day. The excisional biopsy was performed on the tenth day and the samples were submitted for histopathological examination.

Results:

The macroscopic analysis had a significant difference between groups. Microscopic analysis was not significant between groups.

Conclusions:

The topical application of lidocaine and bupivacaine in the surgical wound is feasible and it does not influence skin healing. The benefit of such a practice, which has been the subject of other studies, seems to outweigh the risks.

The Effect of Dexmedetomidine Added to Preemptive Ropivacaine Infiltration on Postoperative Pain After Lumbar Fusion Surgery: A Randomized Controlled Trial

STUDY DESIGN

A prospective and controlled study of dexmedetomidine added to preemptive ropivacaine infiltration in lumbar fusion surgery.

OBJECTIVE

Assessment of dexmedetomidine added to preemptive ropivacaine infiltration for the relief of postoperative pain after lumbar fusion surgery.

SUMMARY OF BACKGROUND DATA

Single local anesthetic preemptive wound infiltration for the relief of postoperative pain does not translate into major or consistent clinical benefits after lumbar fusion surgery. Dexmedetomidine added to local anesthetics prolonged the duration of blockade and enhanced the analgesic in peripheral nerve block. The effect of dexmedetomidine added to preemptive ropivacaine infiltration in lumbar fusion surgery for the relief of postoperative pain has yet not been studied.

METHODS

Fifty-seven patients with elective posterior lumbar fusion were randomly divided into two groups. Five minutes before incision, the skin and subcutaneous tissues were injected with 20 mL 0.5% ropivacaine in group R (n = 28) and 20 mL 0.5% ropivacaine and 1 ug/kg of dexmedetomidine in group RD (n = 29) in two divided doses (i.e., 10 mL per side of the incision line). After the operation, all patients received intravenous morphine for analgesia. The total morphine consumption, the time of first analgesic demand, numbers of PCA analgesia, Visual Analog Scale, and postoperative adverse effects were collected.

RESULTS

In group RD, cumulative morphine dose and numbers of PCA analgesia in group RD were significantly reduced, the time of first analgesic demand was significantly delayed compared to the group R. Visual Analog Scale in group RD showed a marked reduction at 8 hours, 12 hours, 16 hours after operation and less patients in group RD experienced postoperative nausea or vomiting compared to the group R.

CONCLUSION

The addition of dexmedetomidine to preemptive ropivacaine wound infiltration provided a superior analgesic effect, reduced postoperative morphine consumption, and prolonged the time of the first analgesic demand with no serious side effects.

LEVEL OF EVIDENCE

2.

Antimicrobial effects of local anaesthetics

After the introduction of cocaine to the medical practice, local anaesthetics (LA) became essential in pain control. LA infiltration along the incision may be used to provide surgical anaesthesia or postoperative analgesia. This study aimed to compare the antimicrobial effects of the topical antimicrobial agent mupirocine with those of the LA lidocaine and the combination of lidocaine and adrenalin. In our study, the in vitro antimicrobial effects of 1 mL sterile saline, 20 mg/mL mupirocine, 20 mg/mL Lidocaine, and 20 mg/mL Lidocaine and Adrenaline were tested against Staphylococcus aureus American type culture collection (ATCC) 29213, Pseudomonas aeruginosa ATCC 27853, and Escherichia coli ATCC 25922 as Group C (Control), Group M (Mupirocine), Group L (Lidocaine), and Group LA (Lidocaine + adrenaline), respectively. S aureus ATCC 29213, P aeruginosa ATCC 27853, and E coli ATCC 25922 were cultured onto Mueller-Hinton agar (Oxoid, UK) plates for 18 to 24 hours at 37°C. Colonies from these plates were suspended in sterile saline and a 0.5 McFarland turbidity standard suspension (corresponding to 1.5 × 10⁸  CFU/mL) of each isolate was prepared. S Aureus ATCC 29213 inhibition zone diameter values of Group M, Group LA, and Group L were significantly higher compared with the group C (P ˂ 0.05). P aeruginosa ATCC 27853 inhibition zone diameter values of Group M and Group LA were significantly higher compared with the group C (P ˂ 0.05). E coli ATCC 25922 inhibition zone diameter values of Group M, Group LA, and Group L were significantly higher compared to the group C (P ˂ 0.05). LA infiltration along the incision may be used to provide surgical anaesthesia or postoperative analgesia. Considering that LAs show antimicrobial effects besides their analgesic effects, they may contribute to preventing the development and reducing the rate of surgical infections, decreasing the requirement to administer antibiotics. However, caution should be exercised not to antagonise the effective treatment of surgical infections, remembering that controversy on the antimicrobial effects of LAs remains in the literature. Therefore, further comprehensive studies with larger patient populations are warranted to demonstrate the antimicrobial effects of LAs.

[Effects of local anesthetics on wound healing]

INTRODUCTION

Local anesthetic infiltration is used widely for post-operative analgesia in many situations. However the effects of local anesthetics on wound healing are not demonstrated clearly. This study planned to evaluate the effects of lidocaine, prilocaine, bupivacaine and levobupivacaine on wound healing, primarily on wound tensile strength and on collagen ultrastructure.

METHODS

This study was conducted on male Sprague Dawley rats. On days 0, 8th, 15th, and 21st, all animals were weighed and received a preincisional subcutaneous infiltration of 3mL of a solution according the group. Control saline (C), lidocaine (L) 7mg.kg^-1, prilocaine (P) 2mg.kg^-1, bupivacaine (B) 2mg.kg^-1 and levobupivacaine (LVB) 2.5mg.kg^-1. The infiltrations were done at the back region 1.5cm where incision would be performed at the upper, middle and lower part along the midline, under general anesthesia. Wound tensile strengths were measured after 0.7cm×2cm of cutaneous and subcutaneous tissue samples were obtained vertical to incision from infiltrated regions. Tissue samples were also obtained for electron microscopic examination. Evaluations were on the 8th, 15th and 21st days after infiltration.

RESULTS

There was no difference between groups in the weights of the rats at the 0th, 8th, 15th and 21st days. The collagen maturation was no statistically different between groups at the 8th and 15th days. The maturation scores of the B and L groups at the 21st day was significantly lower than the Group C (1.40, 1.64 and 3.56; respectively). The wound tensile strength was no statistically different between groups at the 8th and 15th days but at the 21st day the Groups B and LVB had significantly lower value than Group C (5.42, 5.54 and 6.75; respectively).

CONCLUSION

Lidocaine and prilocaine do not affect wound healing and, bupivacaine and levobupivacaine affect negatively especially at the late period.

Comparison of the effects of gabapentin and pregabalin on wound healing in rats

Gabapentinoids are effective adjunct drugs for reducing postoperative pain. However, the effects of gabapentinoids on wound healing have not been evaluated yet. In this study we evaluated their effects on wound healing. A total of 17 male Wistar-Albino rats, 250-350 g, were divided into three groups randomly: control group (n = 5, 2 ml saline), gabapentin group (n = 6, 20 mg/kg gabapentin) and pregabalin group (n = 6, 20 mg/kg pregabalin). Until day 13 inflammation scores were significantly lower (P < 0·05) and wound healing was significantly better in the control group when compared with gabapentin and pregabalin groups (P < 0·001). Inflammation scores were significantly lower in pregabalin group when compared with gabapentin group until day 13. But wound healing was significantly better in gabapentin group than in pregabalin group between days 13 and 21. In conclusion when gabapentin and pregabalin were compared, although pregabalin decreases inflammation scores, gabapentin has better results in wound healing.

Preperitoneal Continuous Infusion of Local Anesthetics: What Is the Impact on Surgical Wound Infections in Humans?

OBJECTIVE

Continuous surgical wound infusion with local anesthetics is an effective and widely used technique in postoperative pain management. Some aspects of this technique, however, require further investigation. The aim of this study was to retrospectively assess whether continuous infusion of ropivacaine delays the process of wound healing, with an increased incidence of infection.

DESIGN

In total, 244 patients aged between 18 and 75 years, American society of anesthesiology II-III, underwent hepatobiliary pancreatic surgery, were classified into two groups and retrospectively analyzed: group R (Ropivacaine) included 152 patients whose surgical incision was fitted with a preperitoneal catheter continuously infusing ropivacaine. Group C (Control) included 92 patients receiving a total intravenous postoperative analgesia. The evaluation forms of the surgical wound according to the Southampton wound assessment scale (SWAS) were collected at three time points. The main outcome was the rate of patients with surgical site infection within 30 days postoperatively.

RESULTS

Twenty-one patients (13.8%) in group R and 9 patients (9.8%) in group C (P = 0.35) presented wound infection. The rate of patients with a wound evaluation of a SWAS grade IV or V in three time frames in Group R and Group C was T0, 1 (0.7%) and 1 (1.08%) (P = 0.72); T1, 25 (16.4%) and 7 (7.6%) (P = 0.04); T2, 8 (5.3%) and 5 (5.4%) (P = 0.53), respectively.onclusions. The incidence of infection in the surgical site according to the centers for disease control definition was comparable in both groups. The description of the wound healing process according to the SWAS scale shows an initial and temporary decrease in maturation in group R which does not persist in the long-term.

Beneficial effects of levobupivacaine regional anaesthesia on postoperative opioid induced hyperalgesia in diabetic mice

Background

Diabetic neuropathy is one of the most common complications of diabetes and causes various problems in daily life. The aim of this study was to assess the effect of regional anaesthesia on post surgery opioid induced hyperalgesia in diabetic and non-diabetic mice.

Methods

Diabetic and non-diabetic mice underwent plantar surgery. Levobupivacaine and sufentanil were used before surgery, for sciatic nerve block (regional anaesthesia) and analgesia, respectively. Diabetic and non-diabetic groups were each randomly assigned to three subgroups: control, no sufentanil and no levobupivacaine; sufentanil and no levobupivacaine; sufentanil and levobupivacaine. Three tests were used to assess pain behaviour: mechanical nociception; thermal nociception and guarding behaviours using a pain scale.

Results

Sufentanil, alone or in combination with levobupivacaine, produced antinociceptive effects shortly after administration. Subsequently, sufentanil induced hyperalgesia in diabetic and non-diabetic mice. Opioid-induced hyperalgesia was enhanced in diabetic mice. Levobupivacaine associated to sufentanil completely prevented hyperalgesia in both groups of mice.

Conclusion

The results suggest that regional anaesthesia can decrease opioid-induced hyperalgesia in diabetic as well as in non-diabetic mice. These observations may be clinically relevant for the management of diabetic patients.

Clinical profile of levobupivacaine in regional anesthesia: A systematic review

The quest for searching newer and safer anesthetic agents has always been one of the primary needs in anesthesiology practice. Levobupivacaine, the pure S (−)-enantiomer of bupivacaine, has strongly emerged as a safer alternative for regional anesthesia than its racemic sibling, bupivacaine. Levobupivacaine has been found to be equally efficacious as bupivacaine, but with a superior pharmacokinetic profile. Clinically, levobupivacaine has been observed to be well-tolerated in regional anesthesia techniques both after bolus administration and continuous post-operative infusion. The incidence of adverse drug reactions (ADRs) is rare when it is administered correctly. Most ADRs are related to faulty administration technique (resulting in systemic exposure) or pharmacological effects of anesthesia; however, allergic reactions can also occur rarely. The available literary evidence in anesthesia practice indicates that levobupivacaine and bupivacaine produce comparable surgical sensory block, similar adverse side effects and provision of similar labor analgesia with good comparable maternal and fetal outcome. The present review aims to discuss the pharmacokinetic and pharmacological essentials of the safer profile of levobupivacaine as well as to discuss the scope and indications of levobupivacaine based on current clinical evidence.