Laser-assisted anesthesia reduces the pain of venous cannulation in children and adults: a randomized controlled trial

Laser-Assisted Drug Delivery: A Systematic Review of Safety and Adverse Events

Laser-assisted drug delivery (LADD) is an increasingly studied and applied methodology for drug delivery. It has been used in a wide variety of clinical applications. Given the relatively low barrier to entry for clinicians as well as ongoing research in this area, the authors aimed to review outcomes relating to safety in laser-assisted drug delivery. A systematic review was conducted, with the databases PubMed, Medline and Embase searched in September 2022. Included articles were those that mentioned laser-assisted drug delivery in human subjects that also reported adverse effects or safety outcomes. There were no language-based exclusions. Conference abstracts and literature reviews were excluded. The results were then tabulated and categorized according to the application of LADD. In total, 501 articles were obtained. Following deduplication, screening, and full text review 70 articles of various study designs were included. Common findings were erythema, oedema, pain, and crusting following LADD. Several notably more severe adverse effects such as generalized urticaria, infection, scarring and dyspigmentation were noted. However, these events were varied depending on the clinical use of LADD. Relevant negatives were also noted whereby no studies reported life-threatening adverse effects. Limitations included limited details regarding the adverse effects within the full texts, lack of follow-up, and risk of bias. In conclusion, there were multiple adverse effects that clinicians should consider prior to carrying out LADD, where treatment goals and patient tolerability should be considered. Further evidence is needed to quantitatively determine these risks.

Lessons Learned from the First Decade of Laser-Assisted Drug Delivery

Laser-assisted drug delivery augments the distribution and penetration of topically applied treatments, leading to enhanced delivery and bioavailability. We discuss the therapeutic application of laser-assisted drug delivery in clinical practice in cases of non-melanoma skin cancer, vitiligo, melasma, scarring, and alopecia (female pattern hair loss, male pattern hair loss, alopecia areata) as well as for vaccination, local anaesthesia, analgesia, viral warts, infantile haemangiomas and cosmetic uses, and we review clinical studies that have used this technique over the last decade. Our review shows that the application of laser-assisted drug delivery enhances topical agent efficacy, potentially reducing the agent concentration and duration of topical treatment required. Future research into the use of laser-assisted drug delivery before topical therapies is needed to establish the optimal techniques to enhance drug delivery and thus improve patient outcomes.

The Effectiveness of Local Hot and Cold Applications on Peripheral Intravenous Catheterization: A Randomized Controlled Trial

PURPOSE

This study was conducted to examine the effect of local hot and cold applications on pain, anxiety level, insertion time, and vein evaluation before peripheral venous catheter (PVC) insertion.

DESIGN

This randomized controlled trial was conducted with 90 patients who were hospitalized in the cardiology department of a university hospital.

METHODS

All the data were collected using a patient information form, the Numeric Rating Scale, and Vein Assessment Scale for the assessment of pain and anxiety. Before PVC was inserted, the researcher applied a hot application or a cold application to the catheter insertion site for 1 minute.

FINDINGS

Pain level was found to be significantly lower in the hot and cold application groups than the control group, and no difference was determined between the hot and cold application groups. The anxiety levels of the patients were significantly lower in the hot application group than the cold application and control groups (P < .05).

CONCLUSIONS

Applying local hot and cold application before inserting the PVC reduced both pain and anxiety levels of the patients. However, hot application increased vein visibility and patient satisfaction and shortened the insertion time, whereas cold application decreased vein visibility, prolonged the insertion time, and decreased patient satisfaction.

Efficacy of Er,Cr:YSGG laser-assisted delivery of topical anesthesia in the oral mucosa

OBJECTIVE

Lasers which can reduce epithelium thickness will enhance the penetration of topical drugs. To date, no study has assessed the efficacy of this technique in the oral mucosa. The aim of this study was the evaluation of efficacy of this technique in increasing the effect of topical anesthesia in the oral mucosa.

MATERIALS AND METHODS

On 20 volunteers, half of the lower lip mucosa was irradiated with Er,Cr:YSGG laser with 2780 nm wavelength and 1.3 J/cm² energy for 1 min; then, topical lidocaine was applied on the entire lower lip mucosa. After 5 min, a 27-gauge needle was inserted to each half of the lip mucosa, and the length of the needle inserted into the mucosa without feeling pain was considered the depth of insertion. This measurement was repeated every 15 min for 1 h.

RESULTS

The mean depth of anesthesia at the control side was 6.95 ± 2.43, 8.45 ± 4.05, 6.5 ± 3.00, and 3.85 ± 2.08 mm at 5, 20, 35, and 60 min, respectively. These values at the test side were 12.25 ± 5.42, 13.25 ± 5.02, 11.4 ± 5.03, and 9.10 ± 5.84 mm, respectively. According to repeated-measures ANOVA, the effect of the type of the treatment on the depth of insertion was significant (P < 0.001).

CONCLUSIONS

The results showed that irradiation of Er,Cr:YSGG laser before the topical application of the anesthetic agents on the oral mucosa increases their efficacy.

CLINICAL RELEVANCE

Topical anesthesia is used to enhance dental procedures painlessly, but there is controversy in their efficacy. Laser-assisted drug delivery to the oral mucosa can enhance their efficacy.

Randomized, double-blind, phase III clinical study of a novel nanotechnological topical anesthetic formulation containing lidocaine 25 mg/g and prilocaine 25 mg/g (nanorap) in skin phototypes I-III patients with ablative fractional CO2 laser treatment indication in the forehead

BACKGROUND AND OBJECTIVES

Nanotechnology may increase the speed of penetration into the skin. This study evaluated the efficacy, safety, and pharmacokinetics of a novel topical anesthetic nanocapsule formulation (2 g) containing 2.5% lidocaine and 2.5% prilocaine (nanorap-test formulation) compared to placebo (control formulation) in skin types I-III patients of both sexes submitted to the ablative fractional CO₂ laser treatment.

METHODS

The patients (n = 120) included in this double-blind, single-center, randomized trial, received topical application of 2 g of the test formulation (50 mg lidocaine + 50 mg prilocaine) and placebo on the forehead region. Efficacy was assessed as pain sensation in four quadrants of each side of the forehead using a visual analogue scale immediately (0 min) and at 30, 60, and 90 minutes after laser application compared to placebo. The safety and tolerability of the test product were evaluated based on the occurrence of systemic adverse events as well as the occurrence of immediate and late skin reactions. Pharmacokinetic evaluation was performed in plasma of eight patients using a validated LC-MS/MS method for drugs quantification.

RESULTS

Nanorap induced a clinically significant reduction in the pain assessment at all evaluated times (57.2%, 41.6%, 38.6%, and 37.3% at 0, 30, 60, and 90 minutes after drug application, respectively. Mean values of C_max were 14.20 and 5.36 ng/ml and t_max were 3.5 and 1.8 hour for lidocaine and prilocaine, respectively. No systemic adverse events were observed.

CONCLUSION

The nanorap formulation demonstrated a clinically and statistically significant efficacy providing analgesia after the ablative fractional CO₂ laser therapy in the investigated patients, when compared to placebo. The product also presented good safety and tolerability. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.

Does low-level laser therapy enhance the efficacy of intravenous regional anesthesia?

BACKGROUND

The use of intravenous regional anesthesia (IVRA) is limited by pain resulting from the application of tourniquets and postoperative pain.

OBJECTIVE

To assess the efficacy of low-level laser therapy added to IVRA for improving pain related to surgical fixation of distal radius fractures.

METHODS

The present double-blinded, placebo-controlled, randomized clinical trial involved 48 patients who were undergoing surgical fixation of distal radius fractures. Participants were randomly assigned to either an intervention group (n=24), who received 808 nm laser irradiation as 4 J⁄point for 20 s over ipsilateral three nerve roots in the cervical region corresponding to C5-C8 vertebrae, and 808 nm laser irradiation as 0.1 J⁄cm2 for 5 min in a tangential scanning mode over the affected extremity; or a control group (n=24), who underwent the same protocol and timing of laser probe application with the laser switched off. Both groups received the same IVRA protocol using 2% lidocaine.

RESULTS

The mean visual analogue scale scores were significantly lower in the laser-assisted group than in the lidocaine-only group on all measurements during and after operation (P<0.05). The mean time to the first need for fentanyl administration during the operation was longer in the laser group (P=0.04). The total amount of fentanyl administered to patients was significantly lower in the laser-assisted group (P=0.003). The laser group needed significantly less pethidine for pain relief (P=0.001) and at a later time (P=0.002) compared with the lidocaine-only group. There was no difference between the groups in terms of mean arterial pressure and heart rate.

CONCLUSION

The addition of gallium-aluminum-arsenide laser irradiation to intravenous regional anesthesia is safe, and reduces pain during and after the operation.

The effect of SonoPrep® on EMLA® cream application for pain relief prior to intravenous cannulation

The aim the study was to determine the effect of SonoPrep® on the delivery and analgesic effects of EMLA® cream prior to intravenous (iv) cannulation in a tertiary pediatric emergency department. Children aged between 5 and 10 years were enrolled. Patients were randomized to receive either sonophoresis with SonoPrep® or sham sonophoresis followed by application of EMLA® cream for 5 min prior to iv cannulation. The primary outcome measurement was the child's rating of pain immediately after iv placement, using a 10-cm visual analog scale (VAS). Parents or guardians and blinded researchers were additionally asked to rate their perception of the child's pain using the 10-cm VAS and the Wong-Baker Face scale. A total of 42 patients completed the study (21 in the study group, 21 in the control group). The baseline characteristics between the groups were similar. The VAS pain score was significantly lower in children treated with sonophoresis compared with the sham sonophoresis (median (percentiles 25th-75th), 20.0 (10.0-22.5) vs. 60.0 (31.0-87.5); p < 0.001). The parent's perception of the child's pain was significantly lower in the study group vs. the control group by the VAS (median (percentiles 25th-75th), 10.0 (10.0-20.0) vs. 50.0 (15.0-80.0); p < 0.001) and Wong-Baker Face scale (median (percentiles 25th-75th), 2.0 (2.0-2.0) vs. 4.0 (2.5-4.5); p < 0.001). The researcher's evaluation of the child's discomfort was also significantly lower in the study group (2.0 (1.0-3.0) vs. 4.0 (2.5-4.5); p < 0.001). The application of sonophoresis using SonoPrep® followed by the 5-min application of EMLA® cream showed significant benefit in young children in terms of pain reduction and patient satisfaction.

Can fractional lasers enhance transdermal absorption of topical lidocaine in an in vivo animal model?

BACKGROUND AND OBJECTIVE

It has been shown in vitro that pretreatment of skin with fractional lasers enhances transdermal delivery of drugs. The aim of this study is to demonstrate in vivo firstly that laser enhances transdermal drug absorption and secondly that this can be manipulated by altering laser settings.

STUDY DESIGN/MATERIALS AND METHODS

Four pigs were used in the IACUC approved animal study. On day 0, 5 g of 4% topical lidocaine was applied under occlusion for 60 minutes to a 400 cm(2) area on the abdomen. Blood was drawn at 0, 60, 90, 120, 180, and 240 minutes. On day 7, the Er:YAG laser was used at 500, 250, 50, and 25 µm ablative depth, respectively, over a 400 cm(2) area on the abdomen. Five grams of 4% topical lidocaine was applied immediately with occlusion for 60 minutes, and then removed. Blood was drawn at 0, 60, 90, 120, 180, and 240 minutes. The serum was extracted and analyzed for lidocaine and its metabolite monoethylglycinexylidide (MEGX).

RESULTS

Serum levels of lidocaine and MEGX were undetectable in untreated skin. Following laser treatment both lidocaine and MEGX were detectable. Peak levels of lidocaine were significantly higher (P = 0.0002) at 250 µm (0.62 mg/L), compared to 500 µm (0.45 mg/L), 50 µm (0.48 mg/L), and 25 µm (0.3 mg/L). Peak levels of MEGX were significantly higher (P ≤ 0.0001) at 250 µm (0.048 mg/L), compared to 500 µm (0.018 mg/L), 50 µm (0.036 mg/L), and 25 µm (0.0144 mg/L).

CONCLUSIONS

This study demonstrates that laser pretreatment significantly increases absorption of topical lidocaine so that it is detectable in the blood and that manipulating laser settings can affect drug absorption. Future work will look at translating this effect into clinical benefit.

Contribution of a heating element to topical anesthesia patch efficacy prior to vascular access: results from two randomized, double-blind studies

CONTEXT

Pain associated with superficial procedures, including intravenous (IV) access procedures, should be prevented when possible, especially in children.

OBJECTIVES

To evaluate a topical local anesthetic patch containing lidocaine 70 mg/tetracaine 70 mg with a heating element designed to warm the skin and facilitate rapid delivery of local anesthetics into the skin. The pilot study was designed to provide data to inform the design of the definitive study to evaluate the impact of controlled heat on the efficacy of the lidocaine/tetracaine patch (patch) when applied before IV cannulation.

METHODS

Subjects in the pilot study were randomized to eight groups that varied by heated vs. unheated patch, 20 vs. 30 minute application, and 16 vs. 18 G catheter. Subjects in the definitive study were randomized in a double-blind manner to receive either the heated or unheated patch, 20 minutes before vascular access, using a 16 G catheter in the antecubital space of the arm. In both studies, the primary efficacy measure was subject-reported pain intensity using a visual analog scale.

RESULTS

Pilot study: Subjects who received the heated patch (n=43) vs. the unheated patch (n=37) had lower mean pain intensity scores (14.7 vs. 23.5mm, P=0.04). Pain intensity scores did not differ significantly by application time, but the difference between the 16 and 18 G catheter groups approached statistical significance (22.8 vs. 14.9 mm, P=0.05). Definitive study: Mean pain intensity scores for the heated patch group (n=124) vs. the unheated patch group (n=126) were 14.2 and 20.5mm, respectively (P=0.006).

CONCLUSION

Heated patches provided significantly better pain relief compared with unheated patches. All the subjects tolerated the patches well, with few adverse effects.

Ultrasound-enabled topical anesthesia for pain reduction of phlebotomy for whole blood donation

BACKGROUND

Ultrasound-facilitated delivery of topical anesthetics has been used to achieve effective anesthesia within 5 minutes for venipuncture and the insertion of intravenous access devices, but has never been studied for blood donation.

STUDY DESIGN AND METHODS

This study was a single-center, prospective, randomized, sham treatment-controlled, single-blinded clinical evaluation. Repeat donors were randomly assigned to undergo treatment with ultrasound and topical anesthetic or sham ultrasound and placebo anesthetic before phlebotomy for whole blood donation. The primary outcome measures were pain assessments using the Verbal Categorical Scale (VCS) and the Visual Analogue Scale and the assessment of skin irritation at the target site.

RESULTS

One-hundred subjects were enrolled and all completed the study. Compared to the sham/placebo control group, donors receiving ultrasound/anesthetic had lower pain scores on the VCS (1.81 +/- 0.67 vs. 2.17 +/- 0.68; p = 0.01) and Visual Analog Scale (17.2 +/- 15.5 vs. 27.6 +/- 19.5; p = 0.006). The proportion of subjects in the treatment group who experienced skin irritation (8%) was similar to that in the control group (2%; p = 0.20).

CONCLUSION

Ultrasound-enhanced delivery of topical anesthetic was demonstrated to be a safe means of quickly achieving clinically meaningful reduction in the pain of phlebotomy for whole blood donation compared to sham/placebo treatment.

A Comparison of Laser-Assisted Drug Delivery at Two Output Energies for Enhancing the Delivery of Topically Applied LMX-4® Cream Prior to Venipuncture

BACKGROUND

Laser-assisted drug delivery (LAD) has the potential for facilitating topical anesthesia with reduced onset time.

METHODS

In this randomized, double-blind, crossover study we compared the efficacy and adverse event profile of LAD for topical anesthesia before venipuncture using two output energies (2.0 and 3.5 J/cm2).

RESULTS

Mean Visual Analog Scale pain scores were not statistically different (P = 0.57) between the low-energy (mean = 6.7) and high-energy (mean = 8.1) lasers.

CONCLUSIONS

LAD at an energy of 2.0 J/cm2 (570 mJ) is as effective, with similar adverse events, as an energy of 3.5 J/cm2 (1000 mJ) in facilitating topical anesthesia.

Procedural sedation and analgesia research: state of the art

The authors review the current state of procedural sedation and analgesia research and clinical practice in adults and children, discuss the limitations in research methodology, and propose future areas of investigation.