Comprehensive ocular and systemic pharmacokinetics of dexamethasone after subconjunctival and intravenous injections in rabbits.

Even though subconjunctival injections are used in clinics, their quantitative pharmacokinetics has not been studied systematically. For this purpose, we evaluated the ocular and plasma pharmacokinetics of subconjunctival dexamethasone in rabbits. Intravenous injection was also given to enable a better understanding of the systemic pharmacokinetics. Dexamethasone concentrations in plasma (after subconjunctival and intravenous injections) and four ocular tissues (iris-ciliary body, aqueous humour, neural retina and vitreous) were analysed using LC-MS/MS. Population pharmacokinetic modelling for plasma data from both injection routes were used, and for first time the constant rate of absorption of dexamethasone from the subconjunctival space into plasma was estimated (ka,plasma = 0.043 min-1, i.e. absorption half-life of 17.3 min). Non-compartmental analysis was used for the ocular data analysis and resulting in ocular drug exposure of iris-ciliary body (AUC0-∞= 41984 min·ng/g) > neural retina (AUC0-∞= 25511 min·ng/g) > vitreous (AUC0-∞= 7319 min·ng/mL) > aqueous humour (AUC0-∞= 6146 min·ng/mL). The absolute bioavailability values after subconjunctival injection, reported for the first time, were 0.74 % in aqueous humour (comparable to topical dexamethasone suspensions), and 0.30 % in vitreous humour (estimated to be higher than in topical administration). These novel and comprehensive pharmacokinetic data provide valuable information on the potential for exploiting this route in ocular drug development for treating both, anterior and posterior segment ocular diseases. Moreover, the new generated dexamethasone-parameters are a step-forward in building predictive pharmacokinetic models to support the design of new subconjunctival dexamethasone formulations, which may sustain drug effect for longer period of time.

Physical compatibility of Xuebijing injection with 53 intravenous drugs during simulated Y-site administration.

OBJECTIVE: Xuebijing injection (XBJ) is a commonly used herbal medicine injection in China. However, the physical compatibility of XBJ with other intravenous drugs remains unclear. The purpose of this research is to evaluate physical compatibility of Xuebijing injection (XBJ) with 53 intravenous drugs (including 31 Chinese medicine injections and 22 chemicals) during simulated Y-site administration. METHODS: Y-site administration was simulated in vitro by admixing 0.33 ml/ml XBJ with an equal volume of other diluted 53 intravenous drugs, respectively. Physical compatibility including visual inspection, Tyndall beam, particle limits, turbidity, pH, chromacity value, spectroscopic absorption of 550 nm and 420 nm (A550 nm and A420 nm) were observed and assessed at 0, 1, 2, and 4 h. Physical compatibility was defined as all solutions with no color changes, no gas evolution, particulate formation and no Tyndall beam within 4 hours, turbidity changes <0.5 nephelometric turbidity unit (NTU) compared to 0 h, particle limits allowed by the Chinese Pharmacopoeia (Ch.P) 2020 edition, pH changes <10% compared to 0, chromacity value changes <200 compared to 0 h, or photometrical changes of A420 nm <0.0400 or A550 nm <0.0100 compared to 0 h. RESULTS: XBJ was physically incompatible with 27 of the 53 intravenous drugs tested, 26 were compatible with XBJ for 4 h. CONCLUSIONS: XBJ should not be simultaneously co-administered with 27 of the 53 intravenous drugs during simulated Y-site. If coadministration was inevitable, flushing tube with NS or D5W before and after infusion of XBJ was needed. Assessment included visual inspection, Tyndall beam, turbidity measurement, particle counts, pH measurement, chromacity value measurement and absorption of A550 nm were proved to be valid and robust for the quality control of infusion and compatibility of Chinese herbal injection.

Amelioration of diabetic nephropathy in mice by a single intravenous injection of human mesenchymal stromal cells at early and later disease stages is associated with restoration of autophagy.

BACKGROUND AND AIMS: Mesenchymal stromal cells (MSCs) a potentially effective disease-modulating therapy for diabetic nephropathy (DN) but their clinical translation has been hampered by incomplete understanding of the optimal timing of administration and in vivo mechanisms of action. This study aimed to elucidate the reno-protective potency and associated mechanisms of single intravenous injections of human umbilical cord-derived MSCs (hUC-MSCs) following shorter and longer durations of diabetes. METHODS: A streptozotocin (STZ)-induced model of diabetes and DN was established in C57BL/6 mice. In groups of diabetic animals, human (h)UC-MSCs or vehicle were injected intravenously at 8 or 16 weeks after STZ along with vehicle-injected non-diabetic animals. Diabetes-related kidney abnormalities was analyzed 2 weeks later by urine and serum biochemical assays, histology, transmission electron microscopy and immunohistochemistry. Serum concentrations of pro-inflammatory and pro-fibrotic cytokines were quantified by ELISA. The expression of autophagy-related proteins within the renal cortices was investigated by immunoblotting. Bio-distribution of hUC-MSCs in kidney and other organs was evaluated in diabetic mice by injection of fluorescent-labelled cells. RESULTS: Compared to non-diabetic controls, diabetic mice had increases in urine albumin creatinine ratio (uACR), mesangial matrix deposition, podocyte foot process effacement, glomerular basement membrane thickening and interstitial fibrosis as well as reduced podocyte numbers at both 10 and 18 weeks after STZ. Early (8 weeks) hUC-MSC injection was associated with reduced uACR and improvements in multiple glomerular and renal interstitial abnormalities as well as reduced serum IL-6, TNF-α, and TGF-ß1 compared to vehicle-injected animals. Later (16 weeks) hUC-MSC injection also resulted in reduction of diabetes-associated renal abnormalities and serum TGF-ß1 but not of serum IL-6 and TNF-α. At both time-points, the kidneys of vehicle-injected diabetic mice had higher ratio of p-mTOR to mTOR, increased abundance of p62, lower abundance of ULK1 and Atg12, and reduced ratio of LC3B to LC3A compared to non-diabetic animals, consistent with diabetes-associated suppression of autophagy. These changes were largely reversed in the kidneys of hUC-MSC-injected mice. In contrast, neither early nor later hUC-MSC injection had effects on blood glucose and body weight of diabetic animals. Small numbers of CM-Dil-labeled hUC-MSCs remained detectable in kidneys, lungs and liver of diabetic mice at 14 days after intravenous injection. CONCLUSIONS: Single intravenous injections of hUC-MSCs ameliorated glomerular abnormalities and interstitial fibrosis in a mouse model of STZ-induced diabetes without affecting hyperglycemia, whether administered at relatively short or longer duration of diabetes. At both time-points, the reno-protective effects of hUC-MSCs were associated with reduced circulating TGF-ß1 and restoration of intra-renal autophagy.

A Neonatal Rodent Model of Retroorbital Vein Injection.

Intravenous (iv) injection is the most used route of drug administration in neonates in the clinical setting. Therefore, retroorbital vein injection is an important method for compound administration in research, where successful proof-of-concept studies can progress into much-needed neonatal clinical trials. Most intravenous studies in neonatal rodents use the superficial temporal/facial vein. However, retroorbital injection becomes unreliable in neonatal rodents older than 2 days after the skin darkens and the vein is no longer visible. In the present protocol, we describe the retroorbital injection of the venous sinus in both the neonatal mouse and rat at ages when the superficial temporal vein is no longer visible, but the eyes have not opened yet. Eye-opening facilitates retro-orbital injection by enabling the researcher to clearly see that they are not perforating the eye when inserting the needle. We demonstrate that this technique can be performed in a reliable and reproducible manner without adverse effects. Additionally, we show that it can be used in many studies, such as administering compounds to study neonatal brain injury.

Late/delayed gadolinium enhancement in MRI after intravenous administration of extracellular gadolinium-based contrast agents: is it worth waiting?

The acquisition of images minutes or even hours after intravenous extracellular gadolinium-based contrast agents (GBCA) administration ("Late/Delayed Gadolinium Enhancement" imaging; in this review, further termed LGE) has gained significant prominence in recent years in magnetic resonance imaging. The major limitation of LGE is the long examination time; thus, it becomes necessary to understand when it is worth waiting time after the intravenous injection of GBCA and which additional information comes from LGE. LGE can potentially be applied to various anatomical sites, such as heart, arterial vessels, lung, brain, abdomen, breast, and the musculoskeletal system, with different pathophysiological mechanisms. One of the most popular clinical applications of LGE regards the assessment of myocardial tissue thanks to its ability to highlight areas of acute myocardial damage and fibrotic tissues. Other frequently applied clinical contexts involve the study of the urinary tract with magnetic resonance urography and identifying pathological abdominal processes characterized by high fibrous stroma, such as biliary tract tumors, autoimmune pancreatitis, or intestinal fibrosis in Crohn's disease. One of the current areas of heightened research interest revolves around the possibility of non-invasively studying the dynamics of neurofluids in the brain (the glymphatic system), the disruption of which could underlie many neurological disorders.

Effects of Halloysite Nanotubes and Multi-walled Carbon Nanotubes on Kruppel-like Factor 15-Mediated Downstream Events in Mouse Hearts After Intravenous Injection.

Halloysite nanotubes (HNTs) are nanomaterials (NMs) derived from natural clays and have been considered as biocompatible NMs for biomedical uses. However, the cardiovascular toxicity of HNTs has not been thoroughly investigated. In this study, we compared the cardiotoxicity of HNTs and multi-walled carbon nanotubes (MWCNTs), focusing on the changes in Kruppel-like factor (KLF)-mediated signaling pathways. Mice were intravenously injected with 50 µg NMs, once a day, for 5 days, and then mouse hearts were removed for experiments. While HNTs or MWCNTs did not induce obvious pathological changes, RNA-sequencing data suggested the alterations of KLF gene expression. We further confirmed an increase of Klf15 positive cells, accompanied by changes in Klf15-related gene ontology (GO) terms. We noticed that most of the changed GO terms are related with the regulation of gene expression, and we confirmed that the NMs increased myoneurin (Mynn) but decreased snail family transcriptional repressor 1 (Snai1), two transcription factors (TFs) related with Klf15. Besides, the changed GO terms also include metal ion binding and positive regulation of glucose import, and we verified an increase of phosphoenolpyruvate carboxykinase 1 (Pck1) and insulin receptor (Insr). However, HNTs and MWCNTs only showed minimal impact on cell death signaling pathways, and no increase in apoptotic sites was observed after NM treatment. We concluded that intravenous administration of HNTs and MWCNTs activated a protective TF, namely Klf15 in mouse aortas, to alter gene expression and signaling pathways related with metal ion binding and glucose import.

Pharmacokinetics of intravenous and topical lidocaine in patients undergoing thoracoscopic pulmonary resection: a comparative study.

OBJECTIVE: Lidocaine was the commonly used local anesthetic. The present study aimed to compare the pharmacokinetics of intravenous and topical lidocaine in patients undergoing thoracoscopic pulmonary resection. PATIENTS AND METHODS: Sixty patients who were scheduled for thoracoscopic pulmonary resection were screened and randomly assigned to the intravenous lidocaine group and topical lidocaine group. After induction, the patient in the intravenous group was given an intravenous bolus of 1.5 mg/kg lidocaine, while the patient in the topical group was given 3.0 mg/kg lidocaine via the "spray-as-you-go" method. Arterial blood was sampled at preset intervals, and plasma concentrations of lidocaine and its metabolites [monoethylglycinexylidide (MEGX) and glycinexylidide (GX)] were measured by ultra-performance liquid chromatography-tandem mass spectrometry. RESULTS: Following intravenous administration, plasma lidocaine concentration reached its peak with a time to reach Cmax (Tmax) of 0.05 h and then decreased in a biphasic manner with a very short half-life time (T1/2) of 1.85 h. After topical administration, lidocaine was well absorbed, with Tmax of 0.21 h and bioavailability of 71.02%. The mean Tmax, Cmax, and area under the curve from the time (AUC0-t) of MEGX and GX were higher in the topical group than in the intravenous group. There were no obvious differences in the Cmax, T1/2, clearance, or apparent volume of distribution of lidocaine between the two groups. No obvious adverse events were observed. CONCLUSIONS: Topical administration of 3 mg/kg lidocaine via the "spray-as-you-go" method is an effective and safe technology for patients undergoing thoracoscopic pulmonary resection.

Gingival-derived mesenchymal stem cell therapy regenerated the radiated salivary glands: functional and histological evidence in murine model.

BACKGROUND: Radiotherapy in head and neck cancer management causes degeneration of the salivary glands (SG). This study was designed to determine the potential of gingival mesenchymal stem cells (GMSCs) as a cell-based therapy to regenerate irradiated parotid SG tissues and restore their function using a murine model. METHODS: Cultured isolated cells from gingival tissues of 4 healthy guinea pigs at passage 3 were characterized as GMSCSs using flow cytometry for surface markers and multilineage differentiation capacity. Twenty-one Guinea pigs were equally divided into three groups: Group I/Test, received single local irradiation of 15 Gy to the head and neck field followed by intravenous injection of labeled GMSCs, Group II/Positive control, which received the same irradiation dose followed by injection of phosphate buffer solution (PBS), and Group III/Negative control, received (PBS) injection only. Body weight and salivary flow rate (SFR) were measured at baseline, 11 days, 8-, 13- and 16-weeks post-irradiation. At 16 weeks, parotid glands were harvested for assessment of gland weight and histological and immunohistochemical analysis. RESULTS: The injected GMSCs homed to degenerated glands, with subsequent restoration of the normal gland histological acinar and tubular structure associated with a significant increase in cell proliferation and reduction in apoptotic activity. Subsequently, a significant increase in body weight and SFR, as well as an increase in gland weight at 16 weeks in comparison with the irradiated non-treated group were observed. CONCLUSION: The study provided a new potential therapeutic strategy for the treatment of xerostomia by re-engineering radiated SG using GMSCs.

An Explanation of Why Dose-Corrected Area Under the Curve for Alternate Administration Routes Can Be Greater than for Intravenous Dosing.

It is generally believed that bioavailability (F) calculated based on systemic concentration area under the curve (AUC) measurements cannot exceed 1.0, yet some published studies report this inconsistency. We teach and believe, based on differential equation derivations, that rate of absorption has no influence on measured systemic clearance following an oral dose, i.e., determined as available dose divided by AUC. Previously, it was thought that any difference in calculating F from urine data versus that from systemic concentration AUC data was due to the inability to accurately measure urine data. A PubMed literature search for drugs exhibiting F > 1.0 and studies for which F was measured using both AUC and urinary excretion dose-corrected analyses yielded data for 35 drugs. We show and explain, using Kirchhoff's Laws, that these universally held concepts concerning bioavailability may not be valid in all situations. Bioavailability, determined using systemic concentration measurements, for many drugs may be overestimated since AUC reflects not only systemic elimination but also absorption rate characteristics, which is most easily seen for renal clearance measures. Clearance of drug from the absorption site must be significantly greater than clearance following an iv bolus dose for F(AUC) to correctly correspond with F(urine). The primary purpose of this paper is to demonstrate that studies resulting in F > 1.0 and/or greater systemic vs urine bioavailability predictions may be accurate. Importantly, these explications have no significant impact on current regulatory guidance for bioequivalence testing, nor on the use of exposure (AUC) measures in making drug dosing decisions.

Dose-response relationships of intravenous and perineural dexamethasone as adjuvants to peripheral nerve blocks: a systematic review and model-based network meta-analysis.

BACKGROUND: Superiority of perineural over intravenous dexamethasone at extending nerve block analgesia has been suggested but without considering the dose-response relationships for each route of administration. METHODS: Randomised control studies that evaluated intravenous or perineural dexamethasone as an adjuvant to unilateral peripheral nerve blocks in adults were searched up to October 2023 in MEDLINE, Central, Google Scholar, and reference lists of previous systematic reviews. The Cochrane Risk-of-Bias tool was used. A maximum effect (Emax) model-based network meta-analysis was undertaken to evaluate the dose-response relationships of dexamethasone. RESULTS: A total of 118 studies were selected (9284 patients; 35 with intravenous dexamethasone; 106 with perineural dexamethasone; dose range 1-16 mg). Studies with unclear or high risk of bias overestimated the effect of dexamethasone. Bias-corrected estimates indicated a maximum fold increase in analgesia duration of 1.7 (95% credible interval (CrI) 1.4-1.9) with dexamethasone, with no difference between perineural and intravenous routes. Trial simulations indicated that 4 mg of perineural dexamethasone increased the mean duration of analgesia for long-acting local anaesthetics from 11.1 h (95% CrI 9.4-13.1) to 16.5 h (95% CrI 14.0-19.3) and halved the rate of postoperative nausea and vomiting. A similar magnitude of effect was observed with 8 mg of intravenous dexamethasone. CONCLUSIONS: Used as an adjuvant for peripheral nerve block, intravenous dexamethasone can be as effective as perineural dexamethasone in prolonging analgesic duration, but is less potent, hence requiring higher doses. The evidence is limited because of the observational nature of the dose-response relationships and the quality of the included studies. SYSTEMATIC REVIEW PROTOCOL: PROSPERO CRD42020141689.

Practical use of the central venous access port for contrast-enhanced CT: comparison with peripheral intravenous access regarding enhancement and safety.

AIM: To evaluate the efficacy of using the central venous (CV) port compared with peripheral intravenous access for contrast-material injection for contrast enhancement during the portal venous phase. MATERIALS AND METHODS: Patients were divided into three groups: CV delay, CV routine, and peripheral access (PA) groups. Patients in the CV delay group underwent injection in the arm-down position with an additional delay, while those in the CV routine and PA groups underwent injections with the routine injection protocol for portal venous phase imaging. Contrast enhancement was evaluated by measuring the mean radiodensity (Hounsfield units) values for the aortic arch, abdominal aorta, inferior vena cava, portal vein, and spleen. The peak injection pressure was recorded and compared among the three groups. RESULTS: No complications related to power injection were observed during 119 contrast-material injections performed using the CV port device. The CV delay group showed significantly lower radiodensity values than the PA group (165.7 ± 20.1 versus 181 ± 19 HU [p<0.01] for the portal vein); however, no significant differences in mean radiodensity values were observed between the CV routine and PA groups (p>0.05). The median peak injection pressure was 73.5, 67, and 47 psi in the CV delay, CV routine, and PA groups, respectively (p<0.01). CONCLUSION: The CV port can be used for safe contrast-material injection while maintaining contrast enhancement on portal venous phase comparable to that achieved with peripheral intravenous access.

Implementation of a tier system for IVIG indications to address IVIG shortage at a tertiary care pediatric medical center.

BACKGROUND: Drug shortages are a common issue that healthcare systems face and can result in adverse health outcomes for patients requiring inferior alternate treatment. The United States recently experienced a national drug shortage of intravenous immunoglobulin (IVIG). Several reported strategies to address the IVIG and other drug shortages have been proposed; however, there is a lack of evidence-based methods for protocol development and implementation. OBJECTIVE: To evaluate the efficacy of introducing a multidisciplinary task force and tier system of indications and to minimize adverse effects during a shortage of IVIG. METHODS: Faculty members across disciplines with expertise in IVIG use were invited to participate in a task force to address the shortage and ensure adequate supply for emergent indications. A tier system of IVIG indications was established according to the severity of diagnosis, urgency of indication, and quality of supporting evidence. Based on inventory, indications in selected tiers were auto-approved. Orders that could not be automatically approved were escalated for task force review. RESULTS: Overall, there were 342 distinct requests for IVIG during the study period (August 1, 2019 to December 31, 2019). All Tier 1 indications were approved. Of all requests, only 2.6% (9) of requests were denied, none of which resulted in adverse effects based on retrospective chart review. Seven patients who regularly receive IVIG had possible adverse effects due to dose reduction or spacing of treatment; however, each complication was multifactorial and not attributed to the shortage or tier system implementation alone. CONCLUSION: Implementation of a multidisciplinary task force and tier system to appropriately triage high-priority indications for limited pharmaceutical agents should be considered in health institutions faced with a drug shortage.

Pharmacokinetics of intranasal and intramuscular flunixin in healthy grower pigs.

Flunixin meglumine is a nonsteroidal anti-inflammatory drug approved to manage pyrexia associated with swine respiratory disease. In the United States, no analgesic drugs are approved for use in swine by the FDA, although they are needed to manage painful conditions. This study evaluated the pharmacokinetics and relative bioavailability of intranasal versus intramuscular flunixin in grower pigs. Six pigs received 2.2 mg/kg flunixin either intranasally via atomizer or intramuscularly before receiving flunixin via the opposite route following a 5-day washout period. Plasma samples were collected over 60 h and analysed using ultra-performance liquid chromatography and tandem mass spectrometry to detect flunixin plasma concentrations. A non-compartmental pharmacokinetic analysis was performed. The median Cmax was 4.0 µg/mL and 2.7 µg/mL for intramuscular and intranasal administration, respectively, while the median AUCinf was 6.9 h µg/mL for intramuscular administration and 4.9 h µg/mL for intranasal administration. For both routes, the median Tmax was 0.2 h, and flunixin was detectable in some samples up to 60 h post-administration. Intranasal delivery had a relative bioavailability of 88.5%. These results suggest that intranasal flunixin has similar, although variable, pharmacokinetic parameters to the intramuscular route, making it a viable route of administration for use in grower swine.

Comparison of the Effectiveness and Side Effects of Intravenous TPA Injection in Acute Stroke Patients Between 0 and 4.5 Hours and the First 4.5 to 6 Hours From the Onset of Symptoms (P7-5.018).

In the American Academy of Neurology Annual Meeting Abstract "Comparison of the Effectiveness and Side Effects of Intravenous TPA Injection in Acute Stroke Patients Between 0 and 4.5 hours and the First 4.5 to 6 hours From the Onset of Symptoms (P7-5.018)" by Maghbooli et al.,1 Mohammad Bagher Abar should have been included as the second author. The Abstract has been replaced by a corrected version. The authors regret the omission.

Effect of a single intravenous injection of branched chain amino acids on body temperature of cats undergoing general anesthesia.

OBJECTIVE: To evaluate the effect of a single intravenous injection of branched chain amino acids (BCAAs) on body temperature in cats undergoing general anesthesia. STUDY DESIGN: Prospective, blinded, randomized, crossover, experimental study. ANIMALS: A total of 10 healthy adult cats (five female and five male). METHODS: Cats were anesthetized three times with three different treatments in a random order: 3 mL kg-1 lactated Ringer's solution (LRS), 100 mg kg-1 BCAAs (B100) or 200 mg kg-1 BCAAs (B200) solution immediately before induction of anesthesia. After induction, rectal temperature was measured every 5 minutes. Blood samples were collected for the measurement of blood glucose (BG) just before induction, at the end of the 90 minute period of anesthesia, and 24 hours after anesthesia induction. The differences between baseline and each subsequent rectal temperature, and BG measurements were analyzed. Areas under the curve (AUCs) for temperature differences were calculated for each animal for the anesthetic period (AUCT0-90). Parametric or nonparametric data were analyzed by one-way repeated measures anova or Friedman test. A value of p < 0.05 was considered significant. RESULTS: There were no significant differences in AUCT0-90 between groups: 41.6 ± 7.7 for LRS, 43.4 ± 6.9 for B100 and 42.9 ± 7.5 for B200 (p = 0.368). No significant differences were observed in BG between groups at 90 minutes and 24 hours after anesthesia induction (p = 0.283 and p = 0.089, respectively). The incidence of hypoglycemia [BG ≤ 3.17 mmol L-1 (57 mg dL-1)] after anesthesia tended to be higher in both B100 (4/10 cats) and B200 groups (3/10 cats) than in LRS group (1/10 cats). CONCLUSIONS AND CLINICAL RELEVANCE: A single, preanesthetic intravenous injection of BCAAs did not attenuate heat loss during anesthesia. More cats were hypoglycemic in the BCAA groups than in the LRS group.

CT contrast extravasation in children: a single-center experience and systematic review.

BACKGROUND: Extravasation of iodinated contrast material during computed tomography (CT) is a rare complication. A few patients may develop severe complications such as compartment syndrome. OBJECTIVE: The purpose of this study was to retrospectively assess the prevalence, severity, management, and outcome of contrast extravasations in our institution and to perform a comparison to what has been reported in the existing literature. MATERIALS AND METHODS: This is a research ethics board (REB)-approved retrospective study comprising 11 patients who had intravenous contrast-enhanced CT between 2019 and 2022 in a tertiary pediatric center, and experienced extravasation of iodinated contrast as a complication. Age, weight, sex, co-morbidities, angiocatheter size, venous access location, total contrast volume, flow rate, patient's symptoms, severity of injury, and management were collected. For the systematic review, PRISMA guidelines were followed. RESULTS: Only 11 (0.3%) (0.17-0.54 (95%CI)) contrast extravasations occurred in a total of 3638 CTs performed with intravenous contrast during the same period in children. The median age (IQR) was 12.5 (10.0, 15.0) years. In our cohort, 1/11 patients developed compartment syndrome and required fasciotomy. The systematic review assessed 12 articles representing a population of 110 children with extravasations. Pooled prevalence from articles stratified by age was 0.32% (0.06-0.58% (95%CI)). Only three children experienced moderate to severe complications. CONCLUSIONS: We confirm that severe complications of contrast extravasation are rare and can occur at any age. No strong associations were seen with the need for surgical consultation (including age, sex, weight, flow rate, injection site, catheter size, and type of contrast).

Exploring the implementation of role extension for Namibian radiographers: Perspectives on intravenous injection of contrast media.

INTRODUCTION: Role extension to include intravenous (IV) injection of contrast media has been formally embraced by radiographers and their regulatory bodies in developed countries. The revised scope of practice, in our Namibian context, has formalised IV injection as an extended role for radiographers. This study aimed to explore the perspectives of radiographers regarding this new role of IV injection of contrast media. METHODS: A qualitative design with a descriptive phenomenological approach was employed to collect data from 15 radiographers working in both public and private radiology facilities. Participants were purposively selected to participate in focus group discussions and individual interviews. An interview guide was used to facilitate the discussions and interviews, and a voice recorder was used for recording. Data were transcribed verbatim and analysed using Tesch's 8-step method. RESULTS: From the 15 participants, three themes were developed: enhanced service delivery with two subthemes (improved departmental workflow and patient care), training needs with two subthemes (inadequate contrast media reaction training and standardised training requirement), and medical-legal issues with two subthemes (regulatory blurriness and role conflict distress). CONCLUSION: The participants expressed mixed perceptions towards the IV injection role of radiographers, emphasising the benefits for the department and patients while raising concerns regarding standardisation of training and associated medico-legal issues. Furthermore, a large-scale evaluation is necessary to uncover the challenges and barriers to the successful adoption of this new role. IMPLICATIONS FOR PRACTICE: The role extension for radiographers to include IV injections is a long-awaited development, but it should be accompanied by the necessary training and guidelines to fully realise its benefits.