Pain following controlled cutaneous insertion of needles with different diameters

Evaluating nurse preferences for a novel on-body delivery system vs. manual syringes for large-volume subcutaneous drug administration: a survey study

While nurses report challenges with the manual administration of large-volume subcutaneous drugs, these challenges and potential solutions are not captured in the literature. In this cross-sectional study, 45 nurses with experience administering large-volume subcutaneous biologics completed an 18-item survey about preferences for syringes vs. on-body delivery systems. 100% responded that an on-body delivery system seemed easy to learn and use and preferable to syringes. In a drug delivery scenario including comprehensive administration details and assuming equivalent safety and efficacy, 97.78% preferred the on-body delivery system to a daratumumab/hyaluronidase syringe. In the total sample, this preference was primarily attributed to (1) reduced nurse effort due to hands-free delivery, (2) decreased patient pain due to a thinner needle, (3) elimination of needlestick injuries due to a hidden needle, and (4) increased clinic efficiency due to hands-free delivery. 95.56% felt that the on-body delivery system would improve clinic throughput better than syringes. Nurses reported that an on-body delivery system would be easy to learn and use and would improve clinic efficiency and safety. They underscored the importance of decreasing nurse physical burden, needlestick injuries, and patient needle phobia. Contrary to the assumption that speed is paramount, nurses prioritized reducing effort, enhancing administration safety, and improving patient comfort over injection speed.

Advance Insulin Injection Technique and Education With FITTER Forward Expert Recommendations

Injectable insulin therapy is a valuable therapeutic option for millions of people with diabetes worldwide. However, many people with diabetes undergoing insulin therapy experience suboptimal outcomes and/or have complications because of inadequate injection technique and training. Practical, current, evidence-based recommendations are mandatory for primary care practitioners and diabetes specialists alike to address unmet needs in insulin injection technique, education, and consequent outcomes. The most recent global insulin injection technique best practices were published in 2016 by the Forum for Injection Technique and Therapy Expert Recommendations (FITTER). While injection technique efforts in different regions have reflected some developments since 2016, a global effort was warranted to comprehensively capture new evidence and modern expert perspectives. In this article, we share the output of the "FITTER Forward" initiative, authored by 16 diabetes specialists from 13 countries who met virtually in 2023-2024. FITTER Forward provides an updated rationale for the importance of proper injection technique training and its impact on diabetes management. The FITTER Forward recommendations are organized for use in clinical practice and include 4 sections describing (1) the foundational science informing injection device design, experiences, and outcomes, (2) proper injection technique procedures for insulin pens and syringes from insulin storage to needle disposal, (3) lipodystrophy risk reduction, with a focus on lipohypertrophy, and (4) structured injection technique training programs for people with diabetes. Overall, FITTER Forward aims to better equip health care professionals to advance diabetes care by empowering people with diabetes and their caregivers to correctly and safely deliver insulin.

Novel Robust Needle Tip Design Enables Needle Reuse and Reduced Skin Trauma in Combination With Autoinjector Needle Shields

BACKGROUND

Pen needles and autoinjectors are necessary for millions of patients needing injectable drug treatment but pose economic and environmental burdens. A durable device with a multiuse needle could reduce cost and improve user experience. This study explores a novel robust needle tip (EXP) designed for multiple uses and durability against hooking.

METHOD

Needle robustness was investigated through a structural analysis. Furthermore, EXP and control needles (NF30, NF28) were evaluated in an in-vivo porcine model as pen needles or embedded in autoinjectors to study the resulting increase in skin blood perfusion (SBP). The SBP was assessed by laser speckle contrast analysis (LASCA) of 192 randomized and blinded needle insertions.

RESULTS

Forming a 33 µm hook against a hard surface requires 0.92 N for the NF30 control needle and 5.38 N for EXP. The EXP did not induce more tissue trauma than the NF30. There was a positive relation between needle diameter and SBP (P < .05). Furthermore, the presence of an autoinjector shield and applied force of 10 N was found to significantly reduce SBP for worn EXP needles (P < .05) compared to insertions without autoinjector shield.

CONCLUSIONS

The investigated robust needle EXP is on par with the single-use needle NF30 in terms of tissue trauma, which is further reduced by combining the needle with a needle shield. These results should encourage the innovation and development of durable, reusable injection systems with pharmacoeconomic and environmental value and a simplified and enhanced user experience for patients.

International Society for Pediatric and Adolescent Diabetes Clinical Practice Consensus Guidelines 2024: Insulin and Adjunctive Treatments in Children and Adolescents with Diabetes

The International Society for Pediatric and Adolescent Diabetes (ISPAD) guidelines represent a rich repository that serves as the only comprehensive set of clinical recommendations for children, adolescents, and young adults living with diabetes worldwide. This chapter builds on the 2022 ISPAD guidelines, and updates recommendations on the principles of intensive insulin regimens, including more intensive forms of multiple daily injections with new-generation faster-acting and ultra-long-acting insulins; a summary of adjunctive medications used alongside insulin treatment that includes details on pramlintide, metformin, glucagon-like peptide-1 (GLP-1) receptor agonists (GLP-1RA) and sodium-glucose cotransporter inhibitors; and key considerations with regard to access to insulin and affordability to ensure that all persons with diabetes who need insulin can obtain it without financial hardship.

[Evaluation of local anesthesia with buffered Xylocaine in pleural procedures: The DOULAPLUX study]

INTRODUCTION

Pleural procedures are painful interventions. While there exist recommendations aimed at preventing pain induced by local anesthesia, they have never been evaluated with regard to the thoracic wall. The objective of this study was to evaluate the effectiveness of buffered lidocaine local anesthesia in pleural procedures.

METHODS

Descriptive, monocentric, prospective study, including all initial pleural procedures performed in our unit. Pain was assessed 20minutes after the procedure using the VAS (Visual Analog Scale) or the NRS (Numerical Rating Scale).

RESULTS

Two hundred and fifty-one patients were included. The procedures included thoracocentesis (58%), pleural or pulmonary biopsy (28%), or drainage (14%). Average pain intensity was 0.6 on a scale of 10. Over two thirds (68%) of patients had a VAS or NRS score of 0, and 91%≤2. Infectious pleuritis, pneumothorax, and drainage were associated with more pain. The pain levels were acceptable (average VAS/NRS scores of 1.3, 1.8, 1.7 respectively).

CONCLUSION

Buffered lidocaine local anesthesia provides excellent pain control for pleural procedures, regardless of their nature. Recommendations regarding local anesthesia apply to the thoracic wall, and their dissemination is essential to reduction of the pain induced by pleural procedures.

Strategies to minimize procedure-related pain and anxiety: lessons from pediatric dermatology

PURPOSE OF REVIEW

Recent studies have suggested that prolonged or repeated episodes of general anesthesia early in childhood may adversely affect neurodevelopment. This, combined with rising healthcare costs and decreasing access, has sparked interest in performing pediatric procedures in the office setting when possible. It is essential to address the physical and psychological discomfort that often accompany this experience, particularly in children.

RECENT FINDINGS

Healthcare providers performing procedures on children can draw from a spectrum of established techniques, new technology, and novel use of medications to decrease peri-procedural pain and anxiety. These techniques include distraction, optimization of local anesthesia, and mild to moderate sedation.

SUMMARY

We recommend using a combination of techniques to minimize pain and anxiety to improve safety, decrease healthcare costs, improve patient experience, and prevent childhood trauma and persistent negative perception of the healthcare system.

Analysis of Pain and Effectiveness in Digital Block of the First Toe Using Syringe vs. Carpule: Frost's H vs. Modified Frost's H Randomized Clinical Trial

Background: Currently, there is no scientific evidence regarding pain in the anesthetic block of the first toe according to the method of application. However, clinical evidence has highlighted the use of the carpule due to the low pain it causes during the administration of the anesthetic. Most studies on anesthesia and pain, especially using the carpule and distraction methods, belong to the field of dentistry. Objective: To compare the pain and effectiveness between the anesthetic block of the first toe using a carpule and syringe with Frost's H technique and the modified Frost's H technique. Method: A total of 564 subjects were selected and divided into four groups. Subjects were subjected to experimental conditions (randomization through the Random Allocation Software program 2.0), and divided into group 1 = 138 subjects, corresponding to the block with syringe and Frost's H, group 2 = 141 subjects, corresponding to the syringe group and modified Frost's H, group 3 = 141 subjects, corresponding to the carpule group and modified Frost's H, and group 4 = 144 subjects, corresponding to the carpule group and Frost's H. The same researcher generated the random allocation sequence, enrolled the participants, and assigned them to the interventions. Each subject was unaware of the anesthetic procedure assigned by the researcher. Outcome parameters were pain after anesthetic infiltration and its effectiveness. Results: The anesthetic block with carpule showed a lower pain score compared to the anesthetic block with syringe (2.8 vs. 5.3; p < 0.001). However, when analyzing effectiveness, a higher efficacy rate was obtained in the anesthetic blocks performed using the modified Frost's H technique (97.5% vs. 88.1%; p < 0.001). Conclusions: The anesthetic block with carpule and the modified Frost's H technique is less painful and more effective than the traditional anesthetic block.

An Investigation Into Local Infusion Site Pain After Infusion of Ultra Rapid Lispro Excipients Across Sites and Depths

BACKGROUND

This phase 1, randomized, one-day, five-period crossover study in adults with type 1 diabetes on continuous subcutaneous insulin infusion investigated local infusion site pain following infusion of the excipients of ultra rapid lispro (URLi; without insulin) across infusion sites and depths.

METHODS

Forty participants (mean age, 40.5 years; body mass index [BMI], 27.5) were randomized to one of five infusion site sequences consisting of the arm, thigh, buttock (6 mm cannula depth), and abdomen (6 and 9 mm depth). Basal infusion of sodium citrate and treprostinil in diluent with magnesium chloride was initiated (10 μL/h) and at three, six, and nine hours after basal initiation, 15 unit-equivalent boluses (150 μL) were given. Participants rated their pain on a 0 to 100 mm validated visual analog scale (VAS) at 5 minutes pre-bolus and 1 and 15 minutes post-bolus.

RESULTS

At one minute post-bolus, increased VAS scores were occasionally reported. Most one minute post-bolus scores were ≤10 mm (little to no discomfort) while 7 of 577 were >45 mm (generally considered clinically meaningful pain). Painful infusions were reported more frequently for the arm, and mean VAS scores were higher for the arm compared with the thigh and abdomen. The VAS score distributions were similar between cannula depths. By 15 minutes post-bolus, VAS scores returned to pre-bolus levels.

CONCLUSIONS

Local infusion site discomfort after infusion of URLi excipients was reported by a small subset of participants; it was transient, tolerable, and dependent on infusion site but not infusion depth. Given differences within individuals, patients may consider using a different infusion site if they experience discomfort.

CLINICALTRIAL.GOV IDENTIFIER

NCT05067270.

Subjective Discomfort during Botulinumtoxin Injections Dependent on Injection Site and Needle Size: A Comparison Between 30G, 33G and 34G Needles

BACKGROUND

Botulinumtoxin application in the face is amongst the most common aesthetic procedures in the head and neck region. It also has numerous medical uses. One of the main reasons for patients to refrain from it is the subjective discomfort that is experienced during injections.

OBJECTIVES

The study at hand aimed to determine whether needles with 33G and 34G offer an advantage in terms of individual pain perception during botulinumtoxin injections.

METHODS

We conducted a prospective study where patients were asked to grade subjective discomfort on a visual analogue scale for each region (forehead, glabella, temple) that was treated directly after treatment and 15 minutes after. Patients were treated with 30G, 33G or 34G needles, respectively.

RESULTS

Ninety-nine patients that underwent treatment of 189 regions were included in the study. Patients were evenly distributed amongst the different needle sizes and regions. Subjective discomfort was greatest in all regions for 30G needles (3.9  ± 1.6 forehead, 4.3 ± 1.7 glabella and 4.0 ± 1.6 temple) followed by 33G (2.7 ± 1.5 forehead, 2.7 ± 1.9 glabella and 2.2 ± 1.2 temple) and 34G (1.7 ± 1.2 forehead, 1.6 ± 1.4 glabella and 1.6 ± 1.4 temple). All differences between needle size were statistically significant (p < 0.05) CONCLUSION: 33G and 34G needles seem to offer smaller discomfort during BTX treatments of the head and neck, with 34G being superior to 33G.

LEVEL OF EVIDENCE III

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Optimizing pediatric periprocedural pain management part II-Adjunct therapies to support the use of infiltrative anesthetics

Pediatric procedure-related pain management is often incompletely understood, inadequately addressed, and critical in influencing a child's lifelong relationship with the larger healthcare community. We present a comprehensive review of infiltrative anesthetics, including a comparison of their mechanisms of action and relative safety and efficacy data to help guide clinical selection. We also describe the multimodal utilization of adjunct therapies-in series and in parallel-to support the optimization of pediatric periprocedural pain management, enhance the patient experience, and provide alternatives to sedation medication and general anesthesia.

Efficacy of Local Anesthesia for Radial Artery Puncture Pain: A Systematic Review and Network Meta-Analysis

We performed a systematic review and network meta-analysis (NMA) to assist clinicians in determining the optimal patient-specific method of analgesia during radial artery puncture by comparing radial artery puncture procedural pain. We included randomized controlled trials that assessed the prophylactic efficacy of local anesthesia for radial artery puncture-associated pain. We searched the Medical Literature Analysis and Retrieval System Online in January 2023, the Cochrane Central Register of Controlled Trials in January 2023, the Excerpta Medica Database in December 2022, the World Health Organization International Clinical Trials Platform Search Portal in January 2023, and ClinicalTrials.gov in January 2023. We synthesized the pain scores (0-100 scale) using the frequentist random-effects NMA model. We evaluated the confidence in each outcome using the CINeMA tool (https://cinema.ispm.unibe.ch/). We conducted an NMA of 1,619 patients across 14 studies on pain scores during radial artery puncture-related procedures for 12 interventions. Compared with placebo, mepivacaine infiltration and lidocaine spray probably reduce pain (mean difference (MD): -47.67, 95% confidence interval (CI): -61.45 to -33.89, confidence rating (CR): moderate; MD: -27.38, 95% CI: -37.53 to -17.22, CR: moderate). Of the 32 studies included, none reported systemic adverse events, such as anaphylaxis or local anesthetic systemic toxicity, or severe local adverse events. In conclusion, mepivacaine infiltration and lidocaine spray probably reduce the pain associated with radial artery puncture more than other local anesthesia.

Towards more tolerable subcutaneous administration: Review of contributing factors for improving combination product design

Subcutaneous (SC) injections can be associated with local pain and discomfort that is subjective and may affect treatment adherence and overall patient experience. With innovations increasingly focused on finding ways to deliver higher doses and volumes (≥2 mL), there is a need to better understand the multiple intertwined factors that influence pain upon SC injection. As a priority for the SC Drug Development & Delivery Consortium, this manuscript provides a comprehensive review of known attributes from published literature that contribute to pain/discomfort upon SC injection from three perspectives: (1) device and delivery factors that cause physical pain, (2) formulation factors that trigger pain responses, and (3) human factors impacting pain perception. Leveraging the Consortium's collective expertise, we provide an assessment of the comparative and interdependent factors likely to impact SC injection pain. In addition, we offer expert insights and future perspectives to fill identified gaps in knowledge to help advance the development of patient-centric and well tolerated high-dose/high-volume SC drug delivery solutions.

Evaluating unmet needs in large-volume subcutaneous drug delivery: U.S. payer perspectives on a novel, large-volume on-body delivery system

OBJECTIVE

Existing healthcare systems face finite resource allocation and budgetary constraints, resulting in a substantial need for innovative solutions to enhance service delivery at reduced costs. A novel, user-friendly on-body delivery system (OBDS) was developed which enables administration of large-volume subcutaneous (SC) drugs in both clinical and home-based settings (at-home healthcare professional [HCP] administration or at-home self-administration).

METHODS

This research sought to evaluate the potential economic impact of at-home self- or HCP- administration with the OBDS through a comprehensive review of published literature and semi-structured interviews with 17 US payers representing approximately 227 million covered lives.

RESULTS

Published literature on OBDS remains limited, but available research highlights the cost-savings of SC administration due to reduced healthcare resource utilization, particularly with home-based care, and improved patient compliance. In interviews, payers identified several attributes that would help address unmet clinical and economic needs. Clinically, the hidden needle and ease-of-use compared to SC syringe pumps was deemed valuable to improve patient compliance and, as OBDS required minimal training, reduce the risk of administration errors. The flexibility to administer drugs at home (self-administration or HCP-administration) or in-clinic was identified as the most impactful attribute on coverage decision making as it has the greatest potential to reduce costs associated with HCP administration for several therapeutic areas.

CONCLUSIONS

Given the ability to help address critical unmet needs for the patient and healthcare system, a large proportion of the payers stated that the novel OBDS would warrant a price premium versus the cost of the standalone SC vial and certainly over the IV counterpart. Future research to quantify the value that OBDS efficiencies could bring to healthcare delivery are warranted.

Relevance of Adalimumab Product Attributes to Patient Experience in the Biosimilar Era: A Narrative Review

Adalimumab (ADL, Humira®, reference product), an anti-TNF-α biologic, has transformed the treatment of chronic, immune-mediated inflammatory diseases. However, the high cost of ADL therapy has driven the development of more affordable ADL biosimilars, agents with no clinically meaningful differences from the reference product. This review summarizes the product attributes of reference ADL and the nine ADL biosimilars approved and available in the USA in relation to patient experience of injection-site pain (ISP). Product formulation, delivery volume and device features (e.g., type and needle gauge size) influence patient experience of ISP with potential clinical consequences. Citrate-free formulations generally cause less ISP; injection volumes of > 1.5 ml may be associated with increased ISP. Reference ADL and all ADL biosimilars offer a citrate-free formulation, and reference ADL and four ADL biosimilars offer a high-concentration solution that allows a smaller injection volume. All available ADL products are injected subcutaneously using either a pre-filled pen (PFP) or pre-filled syringe (PFS). Patients prefer the PFP, but the PFS permits better control over the speed and duration of injection. Smaller (29-gauge) needle outer diameter is associated with less ISP; reference ADL and seven ADL biosimilars offer a device with a 29-gauge needle. In the USA, an approved biosimilar can be designated "interchangeable," allowing pharmacy-level substitution, where state law permits. In the USA, two ADL biosimilars have received interchangeability designation; others are seeking interchangeability designation from the Food and Drug Administration (n = 2), are being evaluated in clinical studies to support interchangeability (n = 2), or do not have/are not seeking interchangeability designation (n = 3). Product-related attributes influence patient experience of ISP caused by subcutaneous ADL injection. Reference ADL and ADL biosimilar products differ in their attributes, so discussion with patients about treatment options is essential to optimize adherence and outcomes.

Clinical Investigation of Large Volume Subcutaneous Delivery up to 25 mL for Lean and Non-Lean Subjects

PURPOSE

To evaluate the clinical feasibility and tolerability of large volume subcutaneous delivery at different injection depths for lean and non-lean subjects.

METHODS

A single-center, randomized, subject-blinded, crossover study in 62 healthy subjects was conducted to evaluate delivery of a 10-cP solution containing hyaluronic acid. Subjects were separated into lean and non-lean cohort by SC thickness. A syringe pump was used to study the effect of different volumes (5, 12, 25 mL) of a viscous placebo solution and needle lengths (6, 9 and 12 mm) delivered at 0.5 mL/min.

RESULTS

Across all treatments, injection sites were observed to have negligible leakage, ~34 kPa of back pressure, and VAS of mild pain with higher pain from needle insertion than during injection. While mild to moderate erythema was the most frequently reported ISR and edema was most prominent for 25 mL injections, all ISRs were resolved within 4 hours post injection. Subjects were unbothered by ISRs across all treatments and rated them as low distress scores (average 1.0-1.5 out of 6).

CONCLUSION

SC injection of 25 mL is feasible and tolerable using a low-pain formulation for abdomen injection irrespective of subcutaneous thickness and injection depths at a delivery rate of 0.5 mL/min.

Navigating adalimumab biosimilars: an expert opinion

The patent expiry of Humira® in 2018 opened up the current European market to eight adalimumab biosimilars - (in alphabetical order) Amgevita®, Amsparity®, Hulio®, Hukyndra®, Hyrimoz®, Idacio®, Imraldi® and Yuflyma® - for the treatment of various immune and inflammatory conditions. Amjevita, Hadlima®, Hyrimoz and Yuflyma have recently become available in the USA, with others expected to reach this market in 2023 as the US patent protection for Humira ends. Although adalimumab biosimilars demonstrate efficacy, safety and immunogenicity similar to the originator, they may differ in product excipient(s) and preservatives, along with their device type(s). Physicians may find it both difficult and time consuming to navigate their way among the array of available adalimumab biosimilars when they need to make a treatment decision. This article explores the characteristics of various adalimumab biosimilars to help clinicians navigate the various options available across Europe and the USA. In addition to drug selection, effective patient-physician communication is needed to nurture realistic patient expectations and minimise potential nocebo effects when prescribing biosimilars.

Insulin syringe for anesthesia in ptosis surgery: a randomized, fellow eye-controlled clinical study

PURPOSE

Unlike ordinary 30-gauge needles, insulin syringe needles are thinner and shorter and have a comparatively blunt tip. Therefore, insulin syringes may reduce injection discomfort, bleeding, and edema by minimizing tissue damage and vascular penetration. This study aimed to evaluate the potential benefits of using insulin syringes for local anesthesia in ptosis surgery.

METHODS

This randomized, fellow eye-controlled study included 60 patients (120 eyelids), conducted at a university-based hospital. An insulin syringe was used on one eyelid, and a conventional 30-gauge needle was used on the other. Patients were instructed to score pain in both eyelids using a visual analog scale (VAS) ranging from 0 (no pain) to 10 (unbearable pain). Ten minutes after the injection, two observers scored degrees of hemorrhage and edema in both eyelids on five- and four-pointing grading scales (0-4 and 0-3) for each value, and the average score between the two observers was calculated and compared.

RESULTS

The VAS score was 5.17 in the insulin syringe group and 5.35 in the 30-gauge needle group (p = 0.282). Ten minutes after the anesthesia, the median hemorrhage scores were 1.00 and 1.75 (p = 0.010), and the median eyelid edema scores were 1.25 and 2.00 (p = 0.007) in the insulin syringe and 30-gauge needle groups, respectively (Fig. 1).

CONCLUSION

Injecting local anesthesia using an insulin syringe significantly reduces hemorrhage and eyelid edema, but not injection pain, before skin incision. Insulin syringes are useful in patients at high risk of bleeding because they can reduce the penetrative tissue damage caused by needle insertion.

The Usefulness of a Three-Microneedle Device for Indocyanine Green Fluorescence Lymphography

Background: Indocyanine green (ICG) fluorescence lymphography is widely used to diagnose lymphedema. There is little consensus on the appropriate injection method for ICG fluorescence lymphangiography. We used a three-microneedle device (TMD) for skin injection of ICG solution and investigated its usefulness. Methods and Results: Thirty healthy volunteers were injected with ICG solution using a 27-gauge (27G) needle in one foot and a TMD in the other foot. Injection-related pain was evaluated using the Numerical Rating Scale (NRS) and Face Rating Scale (FRS). The skin depth of the injected ICG solution was evaluated by injecting the solution into the skin of amputated lower limbs using a 27G needle or TMD using ICG fluorescence microscopy. The median and interquartile range of the NRS scores was 3 (3-4) and 2 (2-4) in the 27G needle and TMD groups, respectively; that of the FRS scores was 2 (2-3) and 2 (1-2) in the 27G needle and TMD groups, respectively. Injection-related pain was significantly lower with the TMD than with the 27G needle. The lymphatic vessels were similarly visible using both needles. The depth of the ICG solution varied for each injection with a 27G needle (400-1200 μm) and was consistent at ∼300-700 μm below the skin surface using the TMD. Injection depth was significantly different between the 27G needle and the TMD. Conclusions: Injection-related pain decreased using the TMD, and ICG solution depth was consistent on fluorescence lymphography. A TMD may be useful for ICG fluorescence lymphography. Clinical Trials Registry (UMIN-CTR; ID: UMIN000033425).

Needle Technology for Insulin Administration: A Century of Innovation

Innovations in syringe and pen needle (PN) technology over the last 100 years have led to important advances in insulin delivery for people with diabetes, paralleling the strides made in developing recombinant DNA human insulin and insulin analogs with varying onset and duration of action. In this review, the history of advances in insulin delivery is described, focusing on progress in syringe, needle, and PN technologies. The early glass and metal syringes that required sterilization by boiling have been replaced by disposable, single-use syringes or pens with clear labeling for precise insulin dosing. The early needles ranging in length from 19 to 26 mm that required manual sharpening against a whetstone have been replaced by syringe needles of 6 mm and PNs of 4 mm in length as slender as 34 gauge. Imaging studies using ultrasound and computed tomography measured the thickness of skin and subcutaneous tissue layers to show feasibility of targeted insulin administration with shorter needles. These developments, coupled with innovations in needle/PN wall and tip structure, have led to improved injection experience for people with diabetes. It is also important to acknowledge the role of injection technique education, together with these advances in injection technology, for improving clinical outcomes and patient satisfaction. With continued projected growth of diabetes prevalence, particularly in developing countries where expensive and complex insulin delivery systems may not be practical, insulin syringes and pens will continue to serve as reliable and cost-effective means of insulin delivery for people with diabetes.

Monoclonal antibody and protein therapeutic formulations for subcutaneous delivery: high-concentration, low-volume vs. low-concentration, high-volume

Biologic drugs are used to treat a variety of cancers and chronic diseases. While most of these treatments are administered intravenously by trained healthcare professionals, a noticeable trend has emerged favoring subcutaneous (SC) administration. SC administration of biologics poses several challenges. Biologic drugs often require higher doses for optimal efficacy, surpassing the low volume capacity of traditional SC delivery methods like autoinjectors. Consequently, high concentrations of active ingredients are needed, creating time-consuming formulation obstacles. Alternatives to traditional SC delivery systems are therefore needed to support higher-volume biologic formulations and to reduce development time and other risks associated with high-concentration biologic formulations. Here, we outline key considerations for SC biologic drug formulations and delivery and explore a paradigm shift: the flexibility afforded by low-to-moderate-concentration drugs in high-volume formulations as an alternative to the traditionally difficult approach of high-concentration, low-volume SC formulation delivery.

Drug Product Characterization of High Concentration Non-Aqueous Protein Powder Suspensions

High concentration protein formulations for subcutaneous injection represent a substantial number of development projects in the pharmaceutical industry. Such concentrated aqueous protein solutions face some specific challenges such as increased viscosity and aggregation propensity. Protein powder suspensions in non-aqueous vehicles could be an alternative providing lower viscosity than the respective aqueous solution. The choice of potential suspension vehicles is limited as traditional non-aqueous liquids, such as oils, show an inherent high viscosity. We studied suspensions prepared by dispersing spray-dried protein powder in different vehicles including sesame oil and medium chain triglycerides, as well as fluorinated and semifluorinated alkanes. We found, that semifluorinated alkanes enable formulations with high concentrations up to 280 mg/ml monoclonal antibody with a low viscosity of less than 10 mPa·s and low injection forces. The glide force of suspensions containing 210 mg/ml protein was not affected by the particle size of the spray-dried powders with medians ranging from 1 to 14 µm. In contrast, suspensions prepared with cryo-milled powder showed markedly higher viscosities and were not injectable at the same concentration. Protein powder suspensions were syringeable using a 25G needle. Vial filling using a peristaltic pump was possible and lead to a uniform filling. Sedimentation of the suspension was slow and does not lead to challenges upon vial filling during manufacturing or transfer of the suspension into syringes. Thus, we could show that dispersions of spray-dried protein powders in non-aqueous vehicles, such as semifluorinated alkanes, are a promising alternative to aqueous protein solutions at high concentrations.

Effect of local anesthesia on pain scale and specimen adequacy in fine-needle aspiration biopsy of thyroid nodules for liquid-based cytology

Fine-needle aspiration biopsy (FNAB) is a routine diagnostic test for thyroid nodules. The use of local anesthesia (LA) before the procedure is still controversial. This prospective study aimed to evaluate the degree of pain and specimen adequacy in liquid-based cytology (LBC) for FNAB of thyroid nodules with and without LA. A total of 100 consecutive patients with thyroid nodules who underwent FNAB with and without LA between January and December 2020 were included. Patients who received LA had a significantly lower immediate pain scale score (P = 0.01). Multivariate analysis demonstrated that no use of LA (odds ratio [OR] = 3.48, 95% confidence interval [CI] = 1.50-8.10, P = 0.004) and lesion abutting the trachea (OR = 6.14, 95% CI = 1.56-24.12, P = 0.009) were independently and significantly associated with pain degree immediately after FNAB. A higher proportion of patients who previously underwent FNAB thought that LA was helpful and should be performed prior to FNAB. However, the use of LA did not improve the specimen adequacy (P = 0.075). The results showed that administration of LA with a proper technique before ultrasound-guided FNAB might reduce immediate pain after the procedure, and patients may experience more pain when the aspirated nodules abut the trachea.

Gonadotropin-releasing hormone analog therapies for children with central precocious puberty in the United States

Gonadotropin-releasing hormone agonists (GnRHa's) are the standard treatment for children with central precocious puberty (CPP). We aim to present data on available GnRHa options with an easy-to-review table and discuss factors that influence treatment selection. Five GnRHa's are currently FDA-approved and prescribed in the US and published data suggest similar safety and efficacy profiles over the first year of treatment. One- and 3-month intramuscular (IM) leuprolide acetate (LA) have long-term safety and efficacy data and allow for flexible dosing. Six-month IM triptorelin pamoate offers a longer duration of treatment, but without long-term efficacy and outcome data. Six-month subcutaneous (SQ) LA combines a SQ route of injection and long duration of action but lacks long-term efficacy and outcome data. The 12-month SQ histrelin acetate implant avoids injections and offers the longest duration of action, but requires a minor surgical procedure with local or general anesthesia. Factors in treatment selection include route of administration, needle size, injection volume, duration of action, and cost. The current GnRHa landscape provides options with varying benefits and risks, allowing physicians and caregivers to select the most appropriate therapy based on the specific needs and concerns of the child and the caregiver. Agents have different advantages and disadvantages for use, with no one agent displaying superiority.

Local Anesthesia in Interventional Radiology

Interventional radiology is an evolving field that treats a variety of diseases. Local anesthetics is an important component of pain management during interventional radiologic procedures. It is highly effective and generally safe for routine procedures. However, local anesthetics can be associated with painful initial injection, allergic reactions, and rare but potentially devastating systemic toxicities. Recent evidence has shown that buffered solution and warm local anesthetics may reduce injection discomfort and improve clinical efficacy. Sensible safety practices and prompt recognition/treatment of the systemic toxicity are of paramount importance to provide safe local anesthesia. Interventional radiologists should be familiar with the basic pharmacology, common local anesthetics, optimizing strategies, complications, and management to provide safe and effective local anesthesia for patients.

Magnetic Resonance Imaging Used to Define the Optimum Needle Length in Pigs of Different Ages

Intramuscular injections result in tissue destruction and alteration. Therefore, it is necessary to evaluate the optimum injection point for intramuscular injections. As animals—especially pigs—vary in size and explicit information about injection depth is not available. To determine the predicted optimum injection depth, magnetic resonance imaging was used in pigs of different ages and weight groups. In total, 730 magnetic resonance images of 136 pigs were used to calculate the optimum injection depth for intramuscular injections. Four age groups were evaluated: <29 days of age, 29−70 days of age, 71−117 days of age and >170 days of age. For fattening pigs (71−117 days of age), the present study recommends a needle length of 20 mm (range: 40−58 mm). For younger pigs (<70 days of age), a needle length of 12 to 14 mm (range: 10−18 mm), and for older pigs (>170 days of age), a needle length of 30 mm (range: 25−37 mm) is recommended. However, more data are needed. Therefore, further studies are necessary, especially in the youngest (suckling pigs) and oldest (sows) age groups, as these are the groups mainly injected/vaccinated. Additionally, age and weight should be examined in more detail compared to fat distribution in the neck, genetics and the sex of the animal.

Comparison of pain and extent of anesthesia in digital blocks for isolated finger lacerations: A randomized controlled trial

OBJECTIVES:

Digital injuries are among the most common presentations to the emergency department. In order to sufficiently examine and manage these injuries, adequate, prompt, and predictable anesthesia is essential. In this trial, we aim to primarily compare the degree of pain and anesthesia onset time between the two-injection dorsal block technique (TD) and the single-injection volar subcutaneous block (SV) technique. Further, we describe the temporal and anatomical effects of both techniques for an accurate delineation of the anesthetized regions.

METHODS:

This is a single-center prospective randomized controlled trial involving patients presenting with isolated wounds to the fingers requiring primary repair under local anesthesia. Patients were randomized to either the SV or TD blocks. The primary outcome was procedure-related pain (Numerical Rating Scale). Further, we assessed the extent of anesthesia along with the anesthesia onset time.

RESULTS:

A total of 100 patients were included in the final analysis, 50 on each arm of the study. The median pain score during injection was significantly higher in patients who received TD block than patients who received SV block (median [interquartile range] = 4 [2.25, 5.00] vs. 3.00 [2.00, 4.00], respectively, P = 0.006). However, anesthesia onset time was not statistically different among the groups (P = 0.39). The extent of anesthesia was more predictable in the dorsal block compared to the volar block.

CONCLUSION:

The single-injection volar subcutaneous blocks are less painful with a similar anesthesia onset time. Injuries presenting in the proximal dorsal region may benefit from the two-injection dorsal blocks, given the anatomical differences and timely anesthesia of the region.

Recent advances in pain management based on nanoparticle technologies

BACKGROUND

Pain is a vital sense that indicates the risk of injury at a particular body part. Successful control of pain is the principal aspect in medical treatment. In recent years, the advances of nanotechnology in pain management have been remarkable. In this review, we focus on literature and published data that reveal various applications of nanotechnology in acute and chronic pain management.

METHODS

The presented content is based on information collected through pain management publications (227 articles up to April 2021) provided by Web of Science, PubMed, Scopus and Google Scholar services.

RESULTS

A comprehensive study of the articles revealed that nanotechnology-based drug delivery has provided acceptable results in pain control, limiting the side effects and increasing the efficacy of analgesic drugs. Besides the ability of nanotechnology to deliver drugs, sophisticated nanosystems have been designed to enhance imaging and diagnostics, which help in rapid diagnosis of diseases and have a significant impact on controlling pain. Furthermore, with the development of various tools, nanotechnology can accurately measure pain and use these measurements to display the efficiency of different interventions.

CONCLUSIONS

Nanotechnology has started a new era in the pain management and many promising results have been achieved in this regard. Nevertheless, there is still no substantial and adequate act of nanotechnology in this field. Therefore, efforts should be directed to broad investigations.

Injectable Biodegradable Silica Depot: Two Months of Sustained Release of the Blood Glucose Lowering Peptide, Pramlintide

Diabetes mellitus is a major healthcare challenge. Pramlintide, a peptide analogue of the hormone amylin, is currently used as an adjunct with insulin for patients who fail to achieve glycemic control with only insulin therapy. However, hypoglycemia is the dominant risk factor associated with such approaches and careful dosing of both drugs is needed. To mitigate this risk factor and compliance issues related to multiple dosing of different drugs, sustained delivery of Pramlintide from silica depot administered subcutaneously (SC) was investigated in a rat model. The pramlintide-silica microparticle hydrogel depot was formulated by spray drying of silica sol-gels. In vitro dissolution tests revealed an initial burst of pramlintide followed by controlled release due to the dissolution of the silica matrix. At higher dosing, pramlintide released from subcutaneously administered silica depot in rats showed a steady concentration of 500 pM in serum for 60 days. Released pramlintide retained its pharmacological activity in vivo, as evidenced by loss of weight. The biodegradable silica matrix offers a sustained release of pramlintide for at least two months in the rat model and shows potential for clinical applications.

The Effect of Needle Reuse on Piglet Skin Puncture Force

The study investigated whether the repeat use of needles used to inject piglets with iron, influences the force required to puncture into piglet cadaver skin. Pig units (n = 31) were surveyed on needle reuse and injection practices, and these findings informed subsequent laboratory-based experiments on needle puncture force into piglet cadaver tissues. A 21 G 5/8” needle was reported as the most used needle type (67.7%), with 80.6% reporting needle reuse; 38.7% changed the needle between litters or earlier if damaged, 16.1% every three litters and 22.5% when it felt blunt or damaged, after each injection session or when changing the bottle of iron solution. There was a significant difference in puncture force between the 1st and 36th use (p < 0.05), and between the 1st and 100th use (p = 0.0015), but not between the 1st and 12th or 36th use (p > 0.999 and p = 0.8313, respectively). Scanning electron microscopy (SEM) imaging showed appreciable damage to the needle tip after 12 uses. The repeat use of needles in piglet cadavers increased the force of needle puncture compared to first-time use. When extrapolated to live animals, the use of blunt needles has the potential to cause pain and distress.

Subcutaneous Administration: Evolution, Challenges, and the Role of Hyaluronidase

BACKGROUND

The subcutaneous (SC) route has evolved significantly. More than two dozen chemotherapy and supportive therapies have been approved for use in the oncology setting. Several IV therapies have been approved for the SC route and require a significantly higher volume than historical maximum limits. Differences exist in how these drugs are administered as compared to older chemotherapy agents.

OBJECTIVES

The purpose of this article is to provide a brief history of the SC route and describe its role in cancer treatment. The use of recombinant hyaluronidase is reviewed within the context of SC monoclonal antibodies. Proper administration techniques and interventions for reducing patient discomfort are discussed.

METHODS

Sentinel medical texts, pharmacokinetic studies, manufacturer's recommendations, and peer-reviewed articles were examined.

FINDINGS

The SC route offers several advantages over the oral and IV routes. A clear understanding of anatomical site selection and injection techniques is beneficial for providing requisite patient education.

Updates on Wound Infiltration Use for Postoperative Pain Management: A Narrative Review

Local anesthetic wound infiltration (WI) provides anesthesia for minor surgical procedures and improves postoperative analgesia as part of multimodal analgesia after general or regional anesthesia. Although pre-incisional block is preferable, in practice WI is usually done at the end of surgery. WI performed as a continuous modality reduces analgesics, prolongs the duration of analgesia, and enhances the patient’s mobilization in some cases. WI benefits are documented in open abdominal surgeries (Caesarean section, colorectal surgery, abdominal hysterectomy, herniorrhaphy), laparoscopic cholecystectomy, oncological breast surgeries, laminectomy, hallux valgus surgery, and radical prostatectomy. Surgical site infiltration requires knowledge of anatomy and the pain origin for a procedure, systematic extensive infiltration of local anesthetic in various tissue planes under direct visualization before wound closure or subcutaneously along the incision. Because the incidence of local anesthetic systemic toxicity is 11% after subcutaneous WI, appropriate local anesthetic dosing is crucial. The risk of wound infection is related to the infection incidence after each particular surgery. For WI to fully meet patient and physician expectations, mastery of the technique, patient education, appropriate local anesthetic dosing and management of the surgical wound with “aseptic, non-touch” technique are needed.

How to Minimize the Pain of Local Anesthetic Injection for Wide Awake Surgery

After reading this article, the participant should be able to (1) almost painlessly inject tumescent local anesthesia to anesthetize small or large parts of the body, (2) improve surgical safety by eliminating the need for unnecessary sedation in patients with multiple medical comorbidities, and (3) convert many limb and face operations to wide awake surgery. We recommend the following 13 tips to minimize the pain of local anesthesia injection: (1) buffer local anesthetic with sodium bicarbonate; (2) use smaller 27- or 30-gauge needles; (3) immobilize the syringe with two hands and have your thumb ready on the plunger before inserting the needle; (4) use more than one type of sensory noise when inserting needles into the skin; (5) try to insert the needle at 90 degrees; (6) do not inject in the dermis, but in the fat just below it; (7) inject at least 2 ml slowly just under the dermis before moving the needle at all and inject all local anesthetic slowly when you start to advance the needle; (8) never advance sharp needle tips anywhere that is not yet numb; (9) always inject from proximal to distal relative to nerves; (10) use blunt-tipped cannulas when tumescing large areas; (11) only reinsert needles into skin that is already numb when injecting large areas; (12) always ask patients to tell you every time they feel pain during the whole injection process so that you can score yourself and improve with each injection; (13) always inject too much volume instead of not enough volume to eliminate surgery pain and the need for "top ups."

Multiphysics Modeling and Simulation of Subcutaneous Injection and Absorption of Biotherapeutics: Sensitivity Analysis

PURPOSE

A multiphysics simulation model was recently developed to capture major physical and mechanical processes of local drug transport and absorption kinetics of subcutaneously injected monoclonal antibody (mAb) solutions. To further explore the impact of individual drug attributes and tissue characteristics on the tissue biomechanical response and drug mass transport upon injection, sensitivity analysis was conducted and reported.

METHOD

Various configurations of injection conditions, drug-associated attributes, and tissue properties were simulated with the developed multiphysics model. Simulation results were examined with regard to tissue deformation, porosity change, and spatiotemporal distributions of pressure, interstitial fluid flow, and drug concentration in the tissue.

RESULTS

Injection conditions and tissue properties were found influential on the mechanical response of tissue and interstitial fluid velocity to various extents, leading to distinct drug concentration profiles. Intrinsic tissue porosity, lymphatic vessel density, and drug permeability through the lymphatic membrane were particularly essential in determining the local absorption rate of an mAb injection.

CONCLUSION

The sensitivity analysis study may shed light on the product development of an mAb formulation, as well as on the future development of the simulation method.

Preparation of high concentration protein powder suspensions by milling of lyophilizates

Pharmaceutical formulations utilizing protein drugs as powders can be used as drug delivery systems in various ways. Besides powders for inhalation, another promising approach is their use as suspensions in non-aqueous liquids for subcutaneous administration providing high protein stability and good injectability. In this study protein powder suspensions were prepared using a swing-mill. Milling of lyophilizates containing a model monoclonal antibody in presence of the suspension vehicle was compared to cryogenic dry milling. Wet media milling led to injectable suspensions, but resulted in monomer loss and increase in protein aggregation. When the lyophilizates were cryogenic dry ball milled less aggregation and monomer loss were detected. Differences related to protein integrity were found for different process parameters, which were successfully optimized. If not cooled with liquid nitrogen, dry milling resulted in increased damage to the mAb. The type of polyol stabilizer, as well as the protein to stabilizer ratio, did not affect the preservation of protein integrity. As finding the right milling duration is time and resource intensive, a correlation between lyophilizate cake hardness and milling duration was established. Based on this approach high concentration lyophilizates were successfully micronized. Suspensions of cryogenic milled powders lead to clogging of 25G needles, which could be prevented by an additional sieving step. Depending on the suspension vehicle, low viscosity formulations (<10 mPa·s) even at high concentrations (≥100 mg/ml protein concentration) were obtained featuring good injectability.

Comparison of the injection-site experience of the starting doses with semaglutide and dulaglutide: A randomized, double-blind trial in healthy subjects

This double-blind, randomized, single-site, crossover trial compared the injection-site experience with the starting doses of semaglutide and dulaglutide. Healthy subjects (aged 18-75 years; body mass index ≥ 25 kg/m² ; n = 104) were randomized 1:1, using a pregenerated list, to semaglutide 0.25 mg as the first injection and dulaglutide 0.75 mg as the second injection or vice versa; each was administered using their proprietary pen-injectors, according to instructions for use. The primary endpoint was intensity of injection-site pain, measured using a visual analogue scale (VAS; 0 mm = no pain, 100 mm = unbearable pain). Exploratory endpoints included intensity category, duration and quality of injection-site pain, and comparative assessment of injection-site pain with the two injections. The point estimate of the VAS score for injection-site pain intensity was 11.5 mm with dulaglutide versus 5.6 mm with semaglutide; mean (95% confidence interval) estimated treatment difference 5.9 (3.6; 8.2) mm; p < .0001. Other endpoints corroborated a less painful injection experience with semaglutide versus dulaglutide. Safety was consistent with reported data for the drugs. In conclusion, the injection-site experience with semaglutide was rated as less painful than that with dulaglutide.

A Novel Diagnostic Test for End-Stage Sensory Failure Associated With Diabetic Foot Ulceration: Proof-of-Principle Study

BACKGROUND

Diabetic foot ulceration (DFU) affects only a subgroup of patients with diabetic neuropathy, that is, those with pain-insensitivity due to end-stage sensory failure. Pain perception failure develops insidiously and remains asymptomatic until first DFU. As loss of pain perception is clinically significant, timely detection is mandatory.

OBJECTIVES

A novel suprathreshold pinprick pain stimulus of 512 mN force made from optical glass-fiber was explored in a prospective cross-sectional diagnostic accuracy study to detect DFU-related end-stage sensory failure.

METHODS

A total of 116 participants were studied (25 healthy people, 22 patients with diabetes without relevant complications, 19 patients with previous painful foot or leg injuries, and 50 patients with previous or active painless DFU [reference standard]). Palmar and plantar surfaces were stimulated in a standardized fashion. At the feet, the second and third toe skinfolds and the middle of the plantar arch were stimulated. Participants scored stimulated pricking discomfort or pain intensity 0 to 10 on a numerical rating scale.

RESULTS

At hands, intensity was rated on average 5 (1-10) [median (range)] by 114/116 participants. Per foot, participants without DFU scored 5 (1-10), while those with DFU scored 0 (0-3) (P < .0001). At plantar toe skinfolds, the absence of pinprick pain perception detected DFU-associated sensory failure with an accuracy of 99.5% (sensitivity 99.5%, specificity 99.4%, positive likelihood ratio 248, and negative likelihood ratio 0.005).

CONCLUSION

In this pilot study, nociceptive stimulation of a plantar toe skinfold with a 512 mN optical glass-fiber pinprick accurately identified DFU-associated end-stage sensory failure.

A review of Formulations of Commercially Available Antibodies

This review identified 126 commercially available antibodies approved globally between 1986 and February 2021 including 10 antibody drug conjugates, 16 biosimilars, and 3 antibody fragments. Prior to 2014 there were ≤ 5 approved each year, but after 2014 there have been ≥ 7 approved each year with the years 2017, 2019 and 2020 having the most at 17 each. A total of 136 products were identified of which 36 are lyophilized powders and 100 are solutions. The routes of administration are mainly subcutaneous or intravenous infusion with three intravenous bolus, two intravitreal, and one intramuscular. The subcutaneous products are ready-to-use solutions or reconstituted lyophilized powders that do not require dilution while most intravenous products are concentrates that require dilution into saline or another intravenous fluid prior to infusion. Most are packaged in single-dose units and the exception of multi-use is Herceptin® and its biosimilars. The package configurations are vials, prefilled autoinjectors, or prefilled syringes. A typical antibody formulation contains an antibody, an excipient to adjust tonicity or osmolality for solutions or a lyoprotectant for lyophilized powders, a buffer, and a surfactant. The ionic tonicity-adjusting excipient is mainly sodium chloride and the non-ionic osmolality-adjusting excipients include sucrose, trehalose, mannitol, maltose, and sorbitol. The lyoprotectants are trehalose and sucrose. The pH range is 4.8-8.0 and the buffers or pH-modifying agents include histidine, citrate, succinate, acetate, phosphate, glutamate, adipic acid, aspartic acid, lactic acid, tromethamine, and 2-(N-morpholino)-ethanesulfonic acid. The surfactants include mostly polysorbate 20 or polysorbate 80, with four containing poloxamer 188, and one that does not contain a surfactant but contains PEG 3350. One product does not contain a buffer, and 12 do not contain a surfactant. The viscosity-lowering excipients are sodium chloride and the amino acids arginine, glycine, proline, and lysine. Arginine may also function to adjust ionic strength and minimize aggregation. Human serum albumin is used in 2 products for intravenous infusion. Other excipients include methionine as an anti-oxidant, and EDTA or DTPA as chelating agents. The maximum volume of subcutaneous injection is 15 mL administered over 3-5 minutes, but the typically volume is 0.5-2 mL. Five fixed-dose combinations have recently been approved and four contain hyaluronidase to assist the large volume subcutaneous injection of up to 15 mL, while one is a fixed-dose combination for intravenous with three antibodies. Prefilled autoinjectors and syringes are becoming more common and many come affixed with a needle of 27-gauge or 29-gauge, while a few have a 26-gauge or a 30-gauge needle. Recent advancements include hyaluronidase to assist the large subcutaneous injection volume of 5-15 mL, fixed-dose combinations, buffer-free formulation, and smaller subcutaneous injection volume (0.1 mL).

Managing pain associated with dermatologic procedures

Dermatologists are faced with an aging population, accompanied by an increase in the incidence of skin cancer, especially nonmelanoma skin cancer. With this increase in cutaneous malignancy comes an increase in the number of dermatologic procedures being performed. A common concern of dermatologists and dermatology patients is the attenuation and management of pain associated with dermatologic procedures. Fortunately, there are several techniques that may be used in the preoperative, intraoperative, and postoperative periods to manage patient anxiety, minimize injection pain, and safely and effectively treat postoperative pain.

Powder suspensions in non-aqueous vehicles for delivery of therapeutic proteins

Formulating biopharmaceuticals is a challenging task due to their complex and sensitive nature. Protein drugs are typically marketed either as an aqueous solution or as a lyophilizate. Usually aqueous solutions are preferred as neither drying nor reconstitution are required. But it may be unfeasible if the protein features low stability. An interesting alternative to avoid at least reconstitution are protein powder suspensions in non-aqueous vehicles. Such formulations combine the ready-to-use approach with the high protein stability in the solid state. Additionally, protein powder suspensions offer a potentially lower viscosity compared to aqueous solutions at high protein concentrations. Besides injection, other application routes might also benefit from the protein powder approach such as topical or inhalational delivery. Protein powders, which can be dispersed in the non-aqueous suspension vehicle, are usually prepared by spray-drying or freeze-drying with an additional milling step, but other techniques have also been described in literature. An ideal powder preparation technique results in minimum protein damage and yields particle sizes in the lower micrometre range and homogeneous particle size distribution enabling subcutaneous or intramuscular injection through hypodermic needles. As suspension vehicles traditional non-aqueous injectable liquids, such as plant oils, may be selected. But they show an inherent high viscosity, which can lead to unacceptable glide forces during injection. Furthermore, the vehicle should provide high product stability with respect to protein integrity and suspension resuspendability. This review will describe how proteins can be formulated as protein powder suspensions in non-aqueous vehicles for subcutaneous injection including potential vehicles, protein powder preparation techniques, protein and suspension physical stability, as well as the use in the field of high concentration protein formulations.

Effect of two methods and two anaesthetics for local anaesthesia of piglets during castration

Background

Since January 2019, surgical castration of male piglets must be performed using local anaesthesia, if farmers deliver pigs to the primary exporting slaughterhouses according to the “Danish quality scheme”; a voluntary initiative taken by the Danish pig industry. The approved procedure for local anaesthesia in Denmark is a three-step injection method with procaine. A comparison of lidocaine and procaine with the same concentration and injection methods of local anaesthetics has not previously been studied. The purpose of this study was to investigate the effect of two injection methods and two local anaesthetics on piglets’ avoidance behaviour (vocalisation and resistance movements) as well as the time spent on the procedures. The study included 203 male piglets that were randomly assigned to one of five treatments: 1. Control: Sham-handling without injection of local anaesthesia, 2. Pro3: Procaine injection using a three-step method, 3. Pro2: Procaine injection using a two-step method, 4. Lid3: Lidocaine injection using a three-step method, 5. Lid2: Lidocaine injection using a two-step method. During injection of local anaesthesia and castration, vocalisation was measured using a decibel meter and resistance movements were registrated by video recordings.

Results

During castration, piglets treated with local anaesthesia showed significantly reduced vocalisation and resistance movements and time spent on castration was also significantly reduced compared to the control group. During injection of the local anaesthesia, the piglets had significantly increased vocalisation and resistance movements compared to the control group. Piglets injected with lidocaine had a significantly reduced resistance movement score and a tendency to reduced vocalisation compared to piglets injected with procaine. No differences in avoidance behaviour were found between the injection methods.

Conclusions

The use of local anaesthesia, irrespective of the method and local anaesthetic, was effective in reducing vocalisation and resistance movements during surgery as well as the time spent on castration.

Understanding and Minimising Injection-Site Pain Following Subcutaneous Administration of Biologics: A Narrative Review

Injection-site pain (ISP) is a subjective side effect that is commonly reported with the subcutaneous administration of biological agents, yet it may only be a concern to some. Multiple factors related to the product formulation, such as pH, volume and excipients, and/or to the injection process have the potential to contribute to ISP, while patient-related factors, such as low body weight, gender and age, can make an individual more susceptible to experiencing ISP. While total elimination of ISP remains unlikely with any subcutaneously administered agent, it can be minimised by helping the patient to develop a confident and competent injection technique via robust and effective training. Careful management of patient expectations along with open discussion regarding the potential risk of ISP may serve to minimise treatment-related anxieties and, importantly, allow the patient to remain in control of his/her treatment. Other interventions to help minimise ISP include psychological interventions, allowing biologics to reach room temperature prior to injection, using the most suitable injection device for the individual patient and selecting an alternative drug formulation, when available. Productive patient–physician communication remains important in order to support and optimise treatment experience and adherence, while also providing the opportunity for patients to discuss any ISP-related issues.

Consensus on Choice of Insulin Pen Devices in Routine Clinical Practice in India

Although insulin delivery devices are widely used by the patients, there is a paucity of published guidelines to help professionals manage their patients in insulin therapies. To provide simple and easily implementable guidelines to health care physicians on the choice of insulin delivery devices in routine clinical practice, experts in diabetes gathered together and discussed the recommendations at the National insulin Summit 2018. An ideal insulin delivery device should accurately deliver the prescribed dose of insulin and be easy to use. Recommendations are: (1) insulin should be initiated by using an insulin device if the patient seems to discontinue insulin therapy. (2) Pen devices offer accurate dosing than a syringe and vial and are associated with cost savings in the long term. (3) Switching over from syringes and vial to disposable pen devices improves adherence. (4) FlexPen® offers better accuracy, and it requires lower dose force and injection force than SoloStar® and KwikPen® (5). Durable delivery pens such as NovoPen® 4 maintain accuracy and low dose force compared with vials and syringes. (6) One pen should be used by only one patient. (7) Regular counseling on the proper use of the pen device is required regularly. This consensus-based recommendation is a useful reference tool for health care practitioners to initiate insulin therapy in patients with diabetes by using the appropriate insulin pen device.

Biocompatible near-infrared quantum dots delivered to the skin by microneedle patches record vaccination

Accurate medical recordkeeping is a major challenge in many low-resource settings where well-maintained centralized databases do not exist, contributing to 1.5 million vaccine-preventable deaths annually. Here, we present an approach to encode medical history on a patient using the spatial distribution of biocompatible, near-infrared quantum dots (NIR QDs) in the dermis. QDs are invisible to the naked eye yet detectable when exposed to NIR light. QDs with a copper indium selenide core and aluminum-doped zinc sulfide shell were tuned to emit in the NIR spectrum by controlling stoichiometry and shelling time. The formulation showing the greatest resistance to photobleaching after simulated sunlight exposure (5-year equivalence) through pigmented human skin was encapsulated in microparticles for use in vivo. In parallel, microneedle geometry was optimized in silico and validated ex vivo using porcine and synthetic human skin. QD-containing microparticles were then embedded in dissolvable microneedles and administered to rats with or without a vaccine. Longitudinal in vivo imaging using a smartphone adapted to detect NIR light demonstrated that microneedle-delivered QD patterns remained bright and could be accurately identified using a machine learning algorithm 9 months after application. In addition, codelivery with inactivated poliovirus vaccine produced neutralizing antibody titers above the threshold considered protective. These findings suggest that intradermal QDs can be used to reliably encode information and can be delivered with a vaccine, which may be particularly valuable in the developing world and open up new avenues for decentralized data storage and biosensing.

Differential rates of intravascular uptake and pain perception during lumbosacral epidural injection among adults using a 22-gauge needle versus 25-gauge needle: a randomized clinical trial

Background

Inadvertent intravascular injection has been suggested as the most probable mechanism behind serious neurological complications during transforaminal epidural steroid injections. Authors believe a smaller gauge needle may lead to less intravascular uptake and less pain. Theoretically, there is less chance for a smaller gauge needle to encounter a blood vessel during an injection compared to a larger gauge needle. Studies have also shown smaller gauge needle to cause less pain. The aim of the study was to quantify the difference between a 22-gauge needle and 25-gauge needle during lumbosacral transforaminal epidural steroid injection in regards to intravascular uptake and pain perception.

Methods

This was a prospective single blind randomized clinical trial performed at outpatient spine practice locations of two academic institutions. One hundred sixty-two consecutive patients undergoing lumbosacral transforaminal epidural injections from February 2018 to June 2019 were recruited and randomized to each arm of the study – 84 patients were randomized to the 22-gauge needle arm and 78 patients to 25-gauge arm. Each transforaminal injection level was considered a separate incidence, hence total number of incidence was 249 (136 in 22-gauge arm and 113 in 25-gauge arm). The primary outcome measure was intravascular uptake during live fluoroscopy and/or blood aspiration. The secondary outcome measure was patient reported pain during the procedure on the numerical rating scale.

Results

Fisher exact test was used to detect differences between 2 groups in regards to intravascular uptake and paired t-tests were used to detect differences in pain scores. The incidence of intravascular uptake for a 22-gauge needle was 5.9% (95% confidence interval: 1.9 to 9.8%) and for a 25-gauge needle, 7.1% (95% confidence interval: 2.4 to 11.8%) [p = 0.701]. Average numerical rating scale scores during the initial needle entry for 22-gauge and 25-gauge needle was 3.46 (95% confidence interval: 2.94 to 3.98) and 3.13 (95% confidence interval: 2.57 to 3.69) respectively [p = 0.375].

Conclusions

The study showed no statistically significant difference in intravascular uptake or pain perception between a 22-gauge needle and 25-gauge needle during lumbosacral transforaminal epidural steroid injections.

Trial registration

ClinicalTrials.gov NCT04350307. Registered 4/17/2020. (Retrospectively registered).

Fine needle insertion method for minimising deflection in lower abdomen: In vivo evaluation

BACKGROUND

Fine needle insertion in the lower abdomen is difficult because of complex deflections and few image feedbacks. We aim to develop an approach for generating a straight insertion path by minimizing the needle deflection robustly based on a preoperative computer tomography (CT) image.

METHOD

This study presents two approaches: an insertion control strategy that performs both vibration and rotation-assisted needle insertions and a preoperative insertion path planning for determining an optimal insertion path based on insertion angles at each tissue boundary. Those proposed approaches were evaluated through an in vivo experiment with a Landrace mini-pig. We compered the following: (1) the deflection with and without the insertion control strategy in different 10 insertion paths and (2) the score calculated by the path planning and the actual deflection in the 10 insertion paths.

RESULTS

The result shows that the deflection can be reduced significantly by applying the insertion control strategy in the optimal insertion path calculated by the path planning.

CONCLUSION

The proposed method can decrease fine needle deflections in the lower abdomen, which has the potential for accurate and safety procedures without real-time CT imaging.