Optimization of lidocaine application in tumescent local anesthesia

Anatomic Location Influences Duration of Local Lidocaine Anesthesia in Dermatologic Surgery

BACKGROUND

Although the onset and duration of local anesthetics are well-defined, how the anatomic site influences the duration of local anesthetics has not been well characterized in dermatology.

OBJECTIVE

To define the duration of local anesthesia by anatomic site.

MATERIALS AND METHODS

This was a prospective study. Adult healthy volunteers and patients undergoing Mohs micrographic surgery were invited to participate. The nose and the shin were chosen to represent highly and poorly vascularized anatomic sites, respectively. A total of 0.5 mL of buffered 1% lidocaine hydrochloride with 1:100,000 epinephrine was injected subcutaneously into each anatomic site of each participant. A pinprick test was used to assess adequate anesthesia until return of baseline sensation or visit completion.

RESULTS

This study enrolled 25 participants. Time to return of sensation was significantly shorter on the nose compared with the shin ( p < .0001). On the nose, there was an association between male sex and shorter time to return of sensation.

CONCLUSION

Time to return of sensation is significantly shorter on the nasal ala compared with the shin, suggesting that patients may regain sensation sooner on highly vascularized sites. Defining the duration of local anesthetics based on anatomic regions is important for treatment planning in dermatologic procedures.

Clinical Application of Pre-Expanded Perforator Flaps

Background: Challenging large soft tissue defects are typically treated with microvascular free tissue transfer; however, success has been noted with pre-expanded perforator flaps. Objective: To report outcomes and complications from pre-expanded perforator flaps. Methods: A retrospective chart review of patients undergoing tissue reconstruction with pre-expanded perforator flaps between 2014 and 2020. Data collection included flap type, defect characteristics, and complications. Results: All 29 patients had successful flap reconstruction without major complication. The median area of tissue defect was 17 × 13 cm² (range 7 × 4 to 27 × 24 cm²). Mean tissue expansion period was 15.2 weeks (range 9-26 weeks). The most common flap was the pre-expanded internal mammary artery perforator flaps. Conclusion: The findings of this study suggest that combining tissue expansion with a perforator flap for large tissue reconstruction can be successful with limited complications. This technique may allow a larger pliable skin flap that deserves further investigation.

Local anesthesia in oral and maxillofacial surgery: A review of current opinion

Local anesthesia (LA) is the most important pain management process in oral and maxillofacial surgery. Safe and effective LA not only enable patients to obtain high-quality treatment, but also relieve the anxiety of patients when they come to the clinic. The choices of local anesthetic and injection methods determine the success of LA to a great extent. At present, in most countries or regions, common local anesthetics used in oral and maxillofacial surgery belong to amides and they are injected into patients' body mainly through block or infiltration anesthesia. In addition, the operators' technique level, patient's subjective psychology and anatomical variation of maxillofacial structure also have a strong influence on LA in dental clinic. Due to the existence of above factors, the worldwide success rates of LA in oral and maxillofacial surgery is very different. There are no specific LA methods that ensure 100% successful LA rates. Fortunately, the development of new local anesthetic and injection technology are providing us with new ideas to solve this problem. This review mainly report the new research progress on LA in oral and maxillofacial surgery in recent decades and help clinicians with dental LA operation.

A study on reducing the absorption of lidocaine from the airway in cats

Purpose:

To determine if the combination of lidocaine with epinephrine or gamma globulin would decrease the rate or reduce the amount of local absorption of lidocaine through the airway.

Methods:

Twenty adult male cats were randomly and evenly distributed into four groups: 1) Group LG: lidocaine administered with gamma globulin; 2) Group LS: lidocaine administered with physiological saline); 3) Group LE: lidocaine administered with epinephrine; 4) Group C: control group. Invasive blood pressure, heart rate, and concentration of lidocaine were recorded before and after administration.

Results:

The peak of plasma concentrations appeared difference (Group LG: 1.39 ± 0.23 mg/L; Group LS: 1.47 ± 0.29 mg/L and Group LE: 0.99 ± 0.08 mg/L). Compared to Group C, there were significant differences in the average heart rate of Groups LG, LS, and LE (P < 0.05). The average systolic blood pressures were significantly different when each group was compared to Group C (P < 0.05). The biological half-life, AUC0-120, peak time, and half-life of absorption among the three groups have not presented statistically significant differences (P > 0.05).

Conclusion:

Administering lidocaine in combination with gamma globulin through airway causes significant decrease the rate and reduce the amount of local absorption of lidocaine in cats.

The in vitro and in vivo effects of a fast-dissolving mucoadhesive bi-layered strip as topical anesthetics

To overcome pain on injection, the dentist can apply a topical anesthetic spray. Despite the convenience, it is not easy to apply it locally. So, we developed an oral mucoadhesive bi-layer film containing an anesthetic. We used polyvinylpyrrolidone (PVP)/hydroxypropyl methylcellulose (HPMC) and HPMC-only layer as the drug-containing layer and ethyl cellulose (EC) as the backing layer. The lidocaine released was tested in vitro together with the adhesion time and cytotoxicity of the film. Mucosa permeability was tested in vivo. Statistical analysis was performed, with p at 0.05 taken to be significant. The lidocaine was released significantly faster in the PVP/HPMC than HPMC-only group and 80% of the drug was released within 1 min (p<0.05) and they attached at least 3 h. The test groups showed no toxicity and the drug effectively permeated the mucosa (p<0.05). We suggest this new mucoadhesive anesthetic may reduce dental phobia.

Surgical Procedures in Hidradenitis Suppurativa

Hidradenitis suppurativa is difficult to treat owing to its complex pathomechanism; beside the extensive inflammation with abscesses and inflammatory nodules, there is also an architectural loss with sinus tract formation and in severe cases with extensive scarring. Therefore, surgery is mandatory in moderate and severe HS.

Guidelines for the use of local anesthesia in office-based dermatologic surgery

There are an increasing number and variety of dermatologic surgical procedures performed safely in the office setting. This evidence-based guideline addresses important clinical questions that arise regarding the use and safety of local anesthesia for dermatologic office-based procedures. In addition to recommendations for dermatologists, this guideline also takes into account patient preferences while optimizing their safety and quality of care. The clinical recommendations presented here are based on the best evidence available as well as expert opinion.

Comparing cold and warm tumescent anesthesia for pain perception during and after the endovenous laser ablation procedure with 1470 nm diode laser

Objective:

The aim of this study was to compare the pain perception and side effects during and after endovenous laser ablation with a 1470 nm diode laser using cold or room temperature tumescence anesthesia.

Methods:

One hundred and one patients were randomly assigned in two groups. Group A received room temperature (+24℃) and Group B received cold (+4℃) tumescence fluid, which was used for local anesthesia in the track of great saphenous vein. A visual analog score was recorded immediately after the procedure. Patients were asked to register pain scores and the amount of pain medication consumed during the week.

Results:

There was no significant difference concerning gender, age, Clinical Etiological Anatomical Pathological Classification, body mass index, or diameter of the treated vein. In Group A, the mean linear endovenous energy density was 59.5 J/cm and in Group B, it was 60.4 J/cm. The average visual analog score after the endovenous laser ablation procedure in Group A was 5 and in Group B was 2. Third day after the procedure, the average visual analog score in Group A was 3 and in Group B was 1. Patients in Group B needed significantly less analgesics compared with patients in Group A ( p<0.05). The most frequent side effects in both groups were ecchymosis, induration, and minor paraesthesia, all of which were more common in Group A ( p < 0.001).

Conclusions:

To date, most published endovenous laser ablation series describe the use of room temperature tumescence fluid infiltration of the perivenous stroma for tumescent analgesia and protection against thermal injury to the nearby structures. We describe an alternative technique using cold tumescence fluid infiltration, which is equally effective as, but safer than, room temperature tumescence fluid infiltration, and which yields better visual analog scores.

A comparative study of the efficacy of endovenous laser treatment of the incompetent great saphenous under general anesthesia with external air cooling with and without tumescent anesthesia

BACKGROUND

This clinical study reports our experience with endovenous laser treatment (ELT) in which external air cooling is used without classic tumescent anesthesia.

METHODS

Two hundred thirty-two patients underwent ELT under general sedation. In group A (n = 192), ELT was performed with air cooling but without the concurrent use of tumescent anesthesia. In group B (n = 40), patients were treated using the traditional tumescent technique. The parameters were similar for both groups: 980-nm diode laser, power of 15 W, and pulse duration of 1 second. The laser fiber and catheter were manually withdrawn in 3-mm increments. Ultrasound was performed to reevaluate vein closure at the end of surgery and 2 and 8 weeks and 1 year after. During follow-up, complications such as burns, dyschromia, pain, and dysesthesia, as well as time used for surgery were recorded.

RESULTS

A 96% closure rate was obtained in groups A and B at 2 and 8 weeks. This rate remained stable 1 year after the ELT procedure. Except for a higher percentage of ecchymoses in group B (55%) than in group A (0%) (p < 0.001), no significant differences were observed for complications. With external air cooling, ELT took 17.5 minutes to perform for the whole leg, compared with 38.5 minutes when using tumescent anesthesia (p < 0.05).

CONCLUSION

ELT surgery for the great saphenous vein can be safely performed using the air cooling method and is as efficacious as ELT done with tumescent anesthesia but takes significantly less time to perform.

Numerical simulation of endovenous laser treatment of the incompetent great saphenous vein with external air cooling

Endovenous laser treatment (ELT) has been proposed as an alternative in the treatment of reflux of the great saphenous vein. Before the procedure, peri-saphenous subcutaneous tumescent saline solution infiltration is usually performed. However, diffusion of this tumescent fluid is rapidly observed and can potentially reduce the efficacy as a heat sink. External skin cooling with cold air was proposed as an alternative solution. The objective of this study is to compare endovenous laser treatment without and with air cooling by realistic numerical simulations. An optical-thermal damage model was formulated and implemented using finite element modeling. The general model simulated light distribution using the diffusion approximation of the transport theory, temperature rise using the bioheat equation, and laser-induced injury using the Arrhenius damage model. Parameters, used in clinical procedures, were considered: power, 15 W; pulse duration, 1 s; fiber pull back, 3-mm increments every second; cold air applied in continuous mode during ELT; and no tumescent anesthesia. Simulations were performed for vein locations at 5, 10, and 15 mm in depth, with and without air cooling. For a vein located at 15 mm in depth, no significant difference was observed with and without cooling. For a vein located at 10 mm in depth, surface temperature increase up to 45 °C is observed without cooling. For a vein located at 5 mm, without cooling, temperature increase leads to irreversible damage of dermis and epidermis. Conversely, with air cooling, surface temperature reaches a maximum of 38 °C in accordance with recordings performed on patients. ELT of the incompetent great saphenous vein with external air cooling system is a promising therapy technique. Use of cold air on the skin continuously flowing in the area of laser shot decreased significantly the heat extent and the thermal damage in the perivenous tissues and the skin.

Evaluation of the pain in varicose vein surgery under tumescent local anaesthesia using sodium bicarbonate as excipient without any intravenous sedation

Objective

In order to simplify varicose vein surgery, we studied the possibility of tumescent local anaesthesia (TLA) using sodium bicarbonate 1.4% as excipient without any intravenous sedation.

Methods

For three months, 215 patients were included in two centres for ambulatory varicose vein surgery performed without any intravenous sedation. Clinical results and pain were evaluated according to the type and duration of surgery.

Results

Mean perioperative pain was evaluated at 2.7 on a visual scale (0–10). In 91% of the cases, surgery was deemed to be slightly painful. Preoperative pain was not linked to the technical means of surgery but to the psychological and organizational environment of the centre.

Conclusions

In many of the cases, varicose vein surgery could be performed under TLA without any intravenous sedation. Ambulatory varicose vein surgery without any intravenous sedation could be highly cost-effective.