Pain-less injection: principles and pearls.

There has been an exponential growth in the number of dermatologic procedures performed over the past two decades. This surge in procedural volumes is accompanied by increasing utilization of local anesthetics. A proper technique in administering local anesthesia is necessary to minimize pain and promote comfort, as it is often regarded as the most painful part of cutaneous procedures. Pain is a psychophysiological phenomenon that involves attention, cognitive appraisal, and emotion. Sensory feedback and anxiety are two important aspects of pain perception. This article aims to introduce a novel way that minimizes pain and discomfort associated with local anesthetics. It is the authors' experience that painless injection is achievable by keeping syringes/needles out of sight, proceeding with injection without pre-procedure warning, and engaging patients in a conversation or simple tasks.

Immunostimulatory effects on THP-1 cells by peptide or protein pharmaceuticals associated with injection site reactions.

Injection site reaction (ISR) is a common side-effect associated with the use of peptide or protein pharmaceuticals. These types of pharmaceuticals-induced activation of antigen-presenting cells is assumed to be a key step in the pathogenesis of immune-mediated ISR. The present study was designed to evaluate the immunostimulatory properties of peptide or protein pharmaceuticals using human monocytic THP-1 cells. Here, THP-1 cells, with or without phorbol-12-myristate-13-acetate (PMA) pretreatment, were exposed to enfuvirtide and glatiramer acetate (positive controls) or evolocumab (negative control) for 6 or 24 h. PMA treatment differentiated non-adherent monocytic THP-1 (nTHP-1) cells into adherent macrophagic THP-1 (pTHP-1) cells that highly express CD11b and CD36. Enfuvirtide increased the release of cytokines, e.g. TNFα, MIP-1ß, and MCP-1, and expression of CD86 and CD54 on nTHP-1 cells at 24 h. Similar immunostimulatory properties of glatiramer acetate were observed both in the nTHP-1 and pTHP-1 cells at 6 h, but the responses were very weak in the pTHP-1 cells. Evolocumab did not affect cytokine secretion or cell surface marker expression in either cell type. Taken together, these in vitro THP-1 cell assays revealed the immunostimulatory properties of enfuvirtide and glatiramer acetate. This assay platform thus could serve as a powerful tool in evaluating potential immune-related ISR risks of peptide or protein pharmaceuticals in humans.

Residual strain effects in needle-induced cavitation.

Needle-induced cavitation (NIC) locally probes the elastic and fracture properties of soft materials, such as gels and biological tissues. Current NIC protocols tend to overestimate properties when compared to traditional techniques. New NIC methods are needed in order to address this issue. NIC measurements consist of two distinct processes, namely (1) the needle insertion process and (2) the cavitation process. The cavitation process is hypothesized to be highly dependent on the initial needle insertion process due to the influence of residual strain below the needle. Retracting the needle before pressurization to a state in which a cylindrical, tube-like fracture is left below the needle tip is experimentally demonstrated to reduce the impact of residual strain on NIC. Verification of the critical cavitation pressure equation in this new geometry is necessary before implementing this retraction NIC protocol. Complementary modeling shows that the change in initial geometry has little effect on the critical cavitation pressure. Together, these measurements demonstrate that needle retraction is a viable experimental protocol for reducing the influence of residual strain, thus enabling the confident measurement of local elastic and fracture properties in soft gels and tissues.

Treatment of skin soft tissue embolism after hyaluronic acid injection for injection rhinoplasty in Asian patients.

INTRODUCTION: The purpose of this manuscript is to investigate the treatment of skin soft tissue embolization or vascular occlusion after the injection of hyaluronic acid (HA) for Injection Rhinoplasty (IR) in Asians with a special interest in the time occurrence of the occlusion. METHODS: A total of 35 cases were evaluated after receiving HA injections for IR who presented with a vascular occlusive event. They were divided into three stages based on the time to embolization. Immediate, ≤5 hours; early, ≤3 days; and late, >3 days. There were two cases of immediate, 28 deemed early, and five late. Methods to prevent tissue necrosis are reviewed in the manuscript based on these stages. RESULTS: Skin color gradually recovered to normal after 11 treatments in 11 patients with mild embolization. No ischemic aggravation or skin necrosis was observed in 19 patients with moderate embolization; red scarring was seen in two and hypertrophic scar with uneven skin color in one patient. The five patients in the severe category had longer healing, more red scars, and more hypertrophic scarring. CONCLUSION: The treatment of skin soft tissue embolization or vascular occlusion after HA IR in Asians can be effected by identifying the stage and degree of embolization and treating appropriately with the outlines presented in this manuscript.

Acute Histopathologic Findings Related to Needle Puncture Trauma during Subcutaneous Injection in the Sprague-Dawley Rat Model.

It is important to detect injection site reactions during the nonclinical phases of drug development. However, differentiating between normal changes following needle trauma and changes due to the toxicity of injected drugs can be challenging. Therefore, we used the Sprague-Dawley rat model to evaluate the pathological findings expected following a single subcutaneous injection of normal saline. Rats were subcutaneously administered with normal saline, and the injection sites were examined microscopically. Inflammation was evident in most of the injection sites, mostly in minimal severity. Parakeratosis/epithelial crust was also seen in several sites, and necrosis was observed in a minority of the cases. These findings indicate that needle puncture trauma can present with some degree of inflammation and necrosis. Although limited to a specific time point and strain, this study shows that inflammation following subcutaneous injection can be attributed in part to the needle trauma and not necessarily to the drug itself.

Post Filler Ecchymosis Resolution With Intense Pulsed Light

Bruising after dermal filler and neuromodulator injections is a common side effect and can have durations of 1 to 2 weeks. While it ultimately resolves, faster resolution can produce better outcomes for patients and also make patients more likely to return for future treatments. We report the successful reduction in bruising following injections of fillers with an intense pulsed light source. We also documented the onset of action of bruising resolution with serial photographs. Resolution started within the first hour of treatment and continued rapidly over 48 hours. This is the first-time reported study of resolution of bruising from injectables with intense pulsed light. Patient satisfaction is improved when such adverse events are minimized.

Differentiating Nonpermanent Injectable Fillers: Prevention and Treatment of Filler Complications.

Though the incidence of complications and adverse events with dermatological fillers is inherently low, practitioners should be well versed in both prevention of filler complications and the treatment algorithms for addressing "granulomas," nodules, infection, and vascular compromise. Appropriate preventative measures, coupled with timely and effective treatment, are critically important for patient safety and satisfaction. In addition to the preventive measures and treatment algorithms outlined here, the authors emphasize that the broad classification and treatment of nodules as "granulomas" is likely to lead to ineffective treatment, or worse, unnecessary exposure to incorrect treatment. In practice, nodules are classified and treated based on clinical manifestation (eg, late vs early or noninflammatory vs inflammatory) rather than on histology. Indeed, classification of a nodule as a granuloma requires a histological examination, rarely available (or necessary) in clinical practice to guide treatment. Thus, the apparent inflammatory nature of the nodule and the time of onset should drive treatment approach. The treatment algorithms presented here are based on these clinically meaningful parameters.

Pre-emptive ice cube cryotherapy for reducing pain from local anaesthetic injections for simple lacerations: a randomised controlled trial.

OBJECTIVE: Subcutaneous local anaesthetic injection can be painful to patients in the ED. We evaluated the effect of cryotherapy by application of an ice cube to the injection site prior to injection in patients with simple lacerations. METHODS: We conducted a prospective, randomised, controlled trial in consented patients with simple lacerations needing primary repair at a single emergency centre from April to July 2016. We randomly assigned patients undergoing repair for simple lacerations to either the cryotherapy group or the control group (standard care; no cryotherapy or other pretreatment of the injection site). In cryotherapy group subjects, we applied an ice cube (size: 1.5×1.5×1.5 cm) placed inside a sterile glove on the wound at the anticipated subcutaneous lidocaine injection site for 2 min prior to injection. The primary outcome was a subjective numeric rating (0-10 scale) of the perceived pain from the subcutaneous local anaesthetic injections. Secondary outcomes were (a) perceived pain on a numeric scale for cryotherapy itself, that is, pain from contact of the ice cube/glove with the skin and (b) the rate of complications after primary laceration repair. RESULTS: Fifty patients were enrolled, consented and randomised, with 25 in the cryotherapy group and 25 in the control group. The numeric rating scale for subcutaneous anaesthetic injections was median, IQR, 95% CI 2.0 (1 to 3.5), 1.81 to 3.47, respectively, in the cryotherapy group and 5.0 (3 to 7), 3.91 to 6.05 in the control group (Mann-Whitney U=147.50, p=0.001). No wound complications occurred in either group. The numeric rating scale for cryotherapy itself was median, IQR, 95% CI: 2.0 (1 to 3.5), 1.90 to 3.70. CONCLUSION: Pre-emptive topical injection site cryotherapy lasting 2 min before subcutaneous local anaesthetic injections can significantly reduce perceived pain from subcutaneous local anaesthetic injections in patients presenting for simple laceration repair. TRIAL REGISTRATION NUMBER: KCT0001990.

Magnetic Resonance Imaging as a Noninvasive Method for Longitudinal Monitoring of Infusion Site Reactions Following Administration of a Novel Apomorphine Formulation.

Infusion site reactions are common following subcutaneous infusion of drugs. Such reactions can lead to discontinuation of the treatment. Therefore, assessment of such reactions is essential during preclinical safety studies, and magnetic resonance imaging (MRI) can assist in evaluation. Here, in vivo and ex vivo MRI evaluations were used in addition to classical histopathology to assess the infusion site reaction to ND0701, a novel formulation of apomorphine base developed for the treatment of Parkinson's disease, in comparison to the commercial apomorphine hydrochloride (HCl) formulation. Both formulations, each at two concentrations, were continuously administered subcutaneously for 20 hr to each of 3 male and 3 female domestic pigs. Based on MRI evaluations, there was a gradual decrease in the volume of the subcutaneous lesions over 4 weeks, with smaller lesions and quicker resolution with ND0701 at concentrations 2.5- to 5-fold higher when compared to the commercial apomorphine HCl formulation. Histopathological evaluation of ND0701 revealed only minimal inflammation at the sites of infusion, whereas the commercial apomorphine HCl caused persistent inflammatory reactions and necrosis. This study provides support to the use of MRI in preclinical testing of subcutaneous drugs when evaluating local site reactions.

Prevention and Management of Injection-Related Adverse Effects in Facial Aesthetics: Considerations for ATX-101 (Deoxycholic Acid Injection) Treatment.

ATX-101 (deoxycholic acid injection; Kythera Biopharmaceuticals, Inc. [an affiliate of Allergan plc, Dublin, Ireland]) was approved in 2015 in the United States (Kybella) and Canada (Belkyra) for submental fat reduction. As expected, injection-site reactions such as pain, swelling, and bruising, which were mostly mild or moderate and transient, were common adverse events (AEs) reported in clinical trials. An exploratory Phase 3b study investigating interventions for management of injection-site AEs associated with ATX-101 treatment was recently completed. Based on its results, literature review, and our clinical experiences, we have put forward considerations for management of AEs associated with ATX-101 treatment in clinical practice. Pretreatment with oral ibuprofen and/or acetaminophen an hour before treatment and preinjection with epinephrine-containing buffered lidocaine 15 minutes before treatment can help with management of pain and bruising. Cold application to the treated area before and immediately after the procedure may help to reduce pain (if local anesthetic preinjection is not performed) and swelling. Discontinuing medications/supplements that result in increased anticoagulant or antiplatelet activity 7 to 10 days before ATX-101 treatment, when possible, can reduce the risk of bruising. In summary, injection-site AEs associated with ATX-101 treatment can be effectively managed with commonly used interventions.

Local pathology and systemic serum bupivacaine after subcutaneous delivery of slow-releasing bupivacaine microspheres.

BACKGROUND: Prolonged local anesthesia, particularly desirable to minimize acute and chronic postoperative pain, has been provided by microspheres that slowly release bupivacaine (MS-Bup). In this study, we report on the systemic drug concentrations and the local dermatopathology that occur after subcutaneous injection of MS-Bup. METHODS: Rats (approximately 300 g) were injected under the dorsolumbar skin with MS-Bup containing 40 mg of bupivacaine (base) or with 0.4 mL of 0.5% bupivacaine-HCl (BupHCl; 1.78 mg bupivacaine). Blood was drawn, under sevoflurane anesthesia, at 10 minutes to 144 hours, and the serum analyzed for total bupivacaine by liquid chromatography-tandem mass spectrometry. In different animals, skin punch biopsies (4 mm) were taken at 1, 3, 7, 14, and 30 days after the same drug injections, sectioned at 5 µm, and stained with hematoxylin-eosin. Samples from skin injected with BupHCl, with MS-Bup suspended in carboxymethyl cellulose (MS-Bup.CMC), or in methyl cellulose (MS-Bup.MC) were compared with their respective drug-free controls (placebos). RESULTS: Serum bupivacaine reached a maximal average value (n = 8) of 194.9 ng/mL at 8 hours after injection of MS-Bup (95% upper prediction limit = 230.2 ng/mL), compared with the maximal average (n = 6) serum level of 374.9 ng/mL (95% prediction limit = 470.6 ng/mL) at 30 minutes after injection of BupHCl. Serum bupivacaine decreased to undetectable levels (<3.23 ng/mL) at 8 hours after BupHCl and was detectable at approximately 20% of the maximal value at 144 hours after MS-Bup injection. BupHCl injection resulted in moderate lymphocytic infiltration of skeletal muscle at 1 and 3 days. MS-Bup.CMC and placebo-CMC caused extensive infiltration of macrophages, lymphocytes, and some neutrophils at 1 to 7 days, whereas MS-Bup.MC and placebo-MC caused only mild inflammation. CONCLUSIONS: Subcutaneous administration of microspheres releasing bupivacaine results in lower blood levels lasting for much longer times than those from bupivacaine solution.

Minimizing the pain of local anesthesia injection.

BACKGROUND: Local anesthetic injection is often cited in literature as the most painful part of minor procedures. It is also very possible for all doctors to get better at giving local anesthesia with less pain for patients. The purpose of this article is to illustrate and simplify how to inject local anesthesia in an almost pain-free manner. METHODS: The information was obtained from reviewing the best evidence, from an extensive review of the literature (from 1950 to August of 2012) and from the experience gained by asking over 500 patients to score injectors by reporting the number of times they felt pain during the injection process. RESULTS: The results are summarized in a logical stepwise pattern mimicking the procedural steps of an anesthetic injection-beginning with solution selection and preparation, followed by equipment choices, patient education, topical site preparation, and finally procedural techniques. CONCLUSIONS: There are now excellent techniques for minimizing anesthetic injection pain, with supporting evidence varying from anecdotal to systematic reviews. Medical students and residents can easily learn techniques that reliably limit the pain of local anesthetic injection to the minimal discomfort of only the first fine needlestick. By combining many of these conclusions and techniques offered in the literature, tumescent local anesthetic can be administered to a substantial area such as a hand and forearm for tendon transfers or a face for rhytidectomy, with the patient feeling just the initial poke.

Mesotherapy for local fat reduction.

Mesotherapy, which is the injection of substances locally into mesodermally derived subcutaneous tissue, developed from empirical observations of a French physician in the 1950s. Although popular in Europe for many medical purposes, it is used for local cosmetic fat reduction in the United States. This paper reviews manuscripts indexed in PubMed/MEDLINE under 'mesotherapy', which pertains to local fat reduction. The history of lipolytic mesotherapy, the physiology of body fat distribution, the mechanism of action of different lipolytic stimulators and their increased efficacy in combination are reviewed. Mesotherapy falls into two categories. Lipolytic mesotherapy using lipolytic stimulators requires more frequent treatments as the fat cells are not destroyed and can refill over time. Ablative mesotherapy destroys fat cells with a detergent, causes inflammation and scarring from the fat necrosis, but requires fewer treatments. The historic and empiric mixing of sodium channel blocking local anaesthetics in mesotherapy solutions inhibits the intended lipolysis. Major mesotherapy safety concerns include injection site infections from poor sterile technique. Cosmetic mesotherapy directs the area from which fat is lost to improve self-image. Studies were of relatively small number, many with limited sample sizes. Future research should be directed towards achieving a Food and Drug Administration indication rather than continuing expansion of off-label use.

Enzyme-replacement therapy in life-threatening hypophosphatasia.

BACKGROUND: Hypophosphatasia results from mutations in the gene for the tissue-nonspecific isozyme of alkaline phosphatase (TNSALP). Inorganic pyrophosphate accumulates extracellularly, leading to rickets or osteomalacia. Severely affected babies often die from respiratory insufficiency due to progressive chest deformity or have persistent bone disease. There is no approved medical therapy. ENB-0040 is a bone-targeted, recombinant human TNSALP that prevents the manifestations of hypophosphatasia in Tnsalp knockout mice. METHODS: We enrolled infants and young children with life-threatening or debilitating perinatal or infantile hypophosphatasia in a multinational, open-label study of treatment with ENB-0040. The primary objective was the healing of rickets, as assessed by means of radiographic scales. Motor and cognitive development, respiratory function, and safety were evaluated, as well as the pharmacokinetics and pharmacodynamics of ENB-0040. RESULTS: Of the 11 patients recruited, 10 completed 6 months of therapy; 9 completed 1 year. Healing of rickets at 6 months in 9 patients was accompanied by improvement in developmental milestones and pulmonary function. Elevated plasma levels of the TNSALP substrates inorganic pyrophosphate and pyridoxal 5'-phosphate diminished. Increases in serum parathyroid hormone accompanied skeletal healing, often necessitating dietary calcium supplementation. There was no evidence of hypocalcemia, ectopic calcification, or definite drug-related serious adverse events. Low titers of anti-ENB-0040 antibodies developed in four patients, with no evident clinical, biochemical, or autoimmune abnormalities at 48 weeks of treatment. CONCLUSIONS: ENB-0040, an enzyme-replacement therapy, was associated with improved findings on skeletal radiographs and improved pulmonary and physical function in infants and young children with life-threatening hypophosphatasia. (Funded by Enobia Pharma and Shriners Hospitals for Children; ClinicalTrials.gov number, NCT00744042.).

Contribution of endermology to improving indurations and panniculitis/lipoatrophy at glatiramer acetate injection site.

INTRODUCTION: Endermology is a mechanical massage therapy that enables fat mobilization and body contouring. The authors' aim was to assess the effect of endermology on indurations and panniculitis/lipoatrophy associated with subcutaneous administration of glatiramer acetate in patients with multiple sclerosis (MS). METHODS: This was a multicenter pilot experience carried out in patients with MS treated with glatiramer acetate who showed indurations and/ or panniculitis/lipoatrophy at the injection site. Patients underwent endermology and glatiramer acetate treatment according to clinical practice. The primary endpoint was the change in indurations and/or panniculitis/lipoatrophy after 12 endermology sessions. RESULTS: Between April and July 2011, a total of 13 evaluable patients were included (mean age, 40.7±3.1 years; female, 100%; white, 100%; mean MS duration, 10.1±2.3 years; previous MS treatment, 46.2%; mean glatiramer acetate treatment duration, 27.3±9.5 months). Eleven patients (84.6%) showed local indurations (mean diameter, 3.4±0.5 cm; mean number, 9.0±1.0) and six patients (46.2%) areas of panniculitis/ lipoatrophy (mean number, 5.0±1.1). After 12 endermology sessions, patients with indurations reported having experienced a reduction in size (10 patients [90.9%]; mean diameter, 0.1±0.05 cm; P<0.001) and number of indurations (nine patients [81.8%]; mean number, 2.3±1.1; P<0.005). These indurations completely disappeared from arms, thighs, buttocks, and abdomen in six (75.0%), six (75.0%), two (50.0%), and three (42.9%) patients, respectively. Three of these patients (27.3%) recovered from all indurations. Although panniculitis/lipoatrophy did not completely disappear, all patients reported improvements. Most patients with indurations (63.6%) felt very satisfied and considered endermology very useful for reducing indurations. All patients with panniculitis/lipoatrophy were satisfied and considered to be endermology useful in improving it. In addition, endermology enabled glatiramer acetate tolerance to be improved in most patients (60.0%). CONCLUSION: Endermology may contribute to improving indurations and panniculitis/ lipoatrophy at the site of subcutaneous injection of glatiramer acetate in patients with MS, enabling areas of injection to recover, and treatment tolerance to increase.