Inadvertent Intra-arterial Injection Research Articles

Possible Brainstem Anaesthesia in a Cat after Ultrasound-Guided Retrobulbar Block

A 13-year-old neutered, blue-eyed female Siamese cat with a bodyweight of 4.8 kg was admitted for enucleation of the right eye. An ultrasound guided retrobulbar block with 1 mL of ropivacaine was performed under general anaesthesia. When the tip of the needle was visualised inside the intraconal space, negative aspiration of the syringe before injection and no obvious resistance during injection were confirmed. Instantly, after ropivacaine was administered, the cat became apnoeic, and its heart rate and the blood pressure increased significantly for a short period of time. During surgery, the cat needed cardiovascular support to maintain blood pressure and was under continuous mechanical ventilation. Spontaneous breathing returned 20 min after the end of anaesthesia. Brainstem anaesthesia was suspected, and after recovery, the contralateral eye was examined. A reduced menace response, horizontal nystagmus, mydriasis, and absence of the pupillary light reflex were present. The following day, mydriasis was still present, but the cat was visual and was discharged. The inadvertent intra-arterial injection of ropivacaine was suspected to be the cause of the spread into the brainstem. To the current authors' knowledge, possible brainstem anaesthesia has only been reported in a cat 5 min after a retrobulbar block but never instantly.

Intra-arterial injection of particulate corticosteroids: mechanism of injury.

Mechanism of neurologic complications after epidural spinal injections (ESI) of particulate steroids at the cervical spine include intrathecal injection, epidural hematoma, direct spinal cord injury, and brain stem or cord infarction due to an arterial spasm or inadvertent intra-arterial injection of particulate steroids. At the lumbar spine, there is evidence that a spinal cord infarction secondary to an inadvertent intra-arterial injection of particulate steroids through a transforaminal approach is the leading mechanism.Variations in the arterial supply of the spinal cord help to understand how a lumbar ESI may lead to a spinal cord infarction at the thoracic level. A radiculomedullary artery arising from the lumbar or sacral spine may participate to the supply of the spinal cord. All radicular and radiculomedullary arteries penetrate the spinal canal through the intervertebral foramen. Therefore, its catheterization carries a risk of inadvertent intraarterial injection. An ex vivo animal study has shown that particulate steroids injected in the blood stream produce an immediate and unexpected change of red blood cells into spiculated cells which aggregate and cause arterioles obstruction, while no particulate steroid macroaggregates or vascular spasm were observed. Rare instances of neurologic complications also occurred after ESI performed through a posterior approach. All occurred in previously operated on patients suggesting a pathologic role for the epidural scar.

Healthcare Associated Inadvertent Intra-Arterial Injection as a Cause of Acute Limb Ischemia

Background: The present study aimed to determine the outcome of healthcare related inadvertent intra-arterial injection as a cause of acute upper limb ischemia in terms of limb function and salvageability. Methods: A retrospective observational study was undertaken at the Department of Vascular and Endovascular Surgery, Shaheed Mohtarma Benazir Bhutto Institute Of Trauma, Karachi between 1st January 2020 to 31st December 2021. All patients who presented with ischemia secondary to inadvertent intra-arterial injection between the ages 18-70 years were included in the study. Files of the patients were reviewed and data was gathered to fill proformas. Follow up of the patients was reviewed for up to four months. Acute limb ischemia, limb salvageability, and limb function was assessed post-treatment. Results: In 14 (46.67%) no amputation occurred, 5 (16.67%) had minor amputation while 11 (36.67%) had major amputation. Seriousness of presenting symptoms was significantly associated with major amputation (p = 0.022). The majority of the patients who presented with pain, discoloration, sensory loss, motor loss, and gangrene had major amputations i.e. 4 (36.4%). memory loss was significantly associated with major amputation [8 (72.7%); p<0.0001]. Gangrene was also significantly associated with major amputation [8 (72.7%); p=0.002]. Conclusion: A number of mechanisms, including direct artery damage, arterial spasm, toxicity from the drug, embolism can result in ischemia following intra-arterial drug injection. In order to avoid such incidents and to make prompt diagnosis, healthcare providers should broaden their awareness of typical local injection practices, phases of injection drug use and the hazards connected with it. Keywords: Acute limb ischemia, gangrene, Injections, Intra-Arterial, Ischemia

Skin necrosis following sclerotherapy. Part 2: Risk minimisation and management strategies.

Tissue necrosis is a serious but rare complication of sclerotherapy. Early detection and targeted management are essential to prevent progression and minimise serious complications. In the first instalment of this paper, we reviewed the pathogenic mechanisms of post-sclerotherapy necrosis. Here, we describe risk minimisation and management strategies.Risk factors must be addressed to reduce the chance of necrosis following sclerotherapy. These may be treatment-related including poor choice of sclerosant type, concentration, volume or format, poor injection technique, suboptimal ultrasound visualisation and treatment of vessels in high-risk anatomical areas. Risk factors specific to individual patients should be identified and optimised pre-operatively.Tissue necrosis is more likely to occur with extravasation of irritant sclerosants such as absolute alcohol, sodium iodide, bleomycin and hypertonic saline, whereas extravasation of foam detergent sclerosants rarely results in tissue loss. Proposed treatments for extravasation of irritant sclerosants include infiltration of an isotonic fluid and hyaluronidase. Management of inadvertent intra-arterial injections may require admission for neurovascular observation and monitoring for ischaemia, intravenous systemic steroids, anticoagulation, thrombolysis and prostanoids infusion when required. Treatment of veno-arteriolar reflex vasospasm (VAR-VAS) necrosis follows the same protocol involving systemic steroids but rarely requires hospital admission and may not require anticoagulation.In general, treatment of post-sclerotherapy necrosis is challenging and most proposed treatment measures are not evidence-based and only supported by anecdotal personal experience of clinicians. Despite all measures, once the necrosis has set in, it is very difficult to reverse the process and all measures described here may only be useful in prevention of progression and extension of the ulceration.Mid to long-term measures include addressing exacerbating factors, management of medical and psychosocial comorbidities, treatment of secondary infections and referrals to relevant specialists. All ulcers should be managed with compression and prescribed dressing regimes in line with the healing stage of the ulcer.

Skin necrosis following sclerotherapy. Part 1: Differential diagnosis based on classification of pathogenic mechanisms.

Background: Tissue necrosis is a significant but uncommon complication of sclerotherapy. The pathogenic mechanisms of this often-debilitating complication have been poorly described in the literature.Purpose: To elucidate the pathological mechanisms, we propose a morphological approach to classify sclerotherapy-induced skin necrosis into two categories of round and stellate (star-like) necrosis.Research Design: Comprehensive literature review was conducted.Results: Round necrosis is typically caused by extravasation of sclerosants. It typically presents as an ulcer with smooth and non-geographic borders. Historically, extravasation has been cited as the main cause of sclerotherapy-related necrosis. While this may be the case with osmotic or irritant sclerosants, it is far less likely with the use of detergent agents particularly in the foam format.The more commonly encountered pattern of stellate necrosis is an ischaemic ulcer secondary to arterial/arteriolar occlusion. In contrast to round necrosis, stellate necrosis follows an intra-vascular injection of sclerosants such as an inadvertent intra-arterial injection. But more frequently, stellate necrosis may follow a perfectly executed intra-venous or intra-telangiectatic delivery of sclerosants. Several pathogenic pathways can be considered. The physiologic response of veno-arteriolar reflex vasospasm (VAR-VAS) is possibly the most frequent pathway. It follows a high-pressure injection of the sclerosant in a target vein resulting in a rapid rise of intravenous pressures which in-turn would trigger a sympathetic neuronal reflex vasospasm of the pre-capillary sphincters and a corresponding opening of the normally closed arterio-venous anastomoses(AVAs). This communication would allow entry of the sclerosing agent into the arteriolar side of the circulation resulting in arteriolar occlusion and infarction of the corresponding skin. Similarly, an intravenous administration of sclerosants in the vicinity of defective boundary valves or persistently open AVAs can result in the entry of detergent agents into the arteriolar side of the microvasculature causing an ischemic stellate ulcer.Conclusions: In this first instalment of these two-part series, we review the pathogenic mechanisms of post-sclerotherapy necrosis. In the second instalment, we describe risk minimisation and management strategies.

Specific pattern of bone scan as a result of unintentional-intraarterial injection into the ulnar artery.

Background:Bone scintigraphy with 99mTc labeled radiopharmaceuticals is a valuable method in nuclear medicine for assessing the bony structure. In clinical setting, bone scintigraphy is accomplished after the injection of 99mTc labeled diphosphonate complexes into a peripheral vein. Inadvertent intra-arterial injection on the antecubital region may cause a special form of artifacts leading to problems inaccurately interpreting these studies as functional images.Case Presentation:We present a 44-year-old man with history of chest wall pain for bone scintigraphy as part of a work-up for determining the pain source. The patient received an injection of 740MBq 99mTc-methylene diphosphonate (MDP) into a blood vessel at the right forearm. Two hours later, an increased uptake of activity was observed on the right forearm and ulnar half of the wrist-hand in the whole body and spot images. The scan findings were consistent with the anatomical and physiological expectations of the ulnar arterial perfusion range. This case displays that an incidental injection with a 99mTc labeled diphosphonate into the ulnar artery results in a hot ulnar half of the palm and ulnar-sided three digits, because these areas are directly exposed to radiopharmaceutical, therefore more radiopharmaceutical is deposited.Conclusion:It is important for the physician, and especially for the nuclear medicine technician, to know the specific appearance created in the bone scan due to such an event so that they do not make a diagnostic mistake.

Management of vascular complications following calcium hydroxylapatite filler injections: a systemic review of cases and experimental studies

Aim: Dermal fillers are increasingly popular procedures. Inadvertent intraarterial injection of fillers, particularly with calcium hydroxylapatite (CaHA), can result in devastating consequences. A systemic review was performed to summarize management strategies to treat CaHA-associated vascular complications. Methods: The methodology of this review was derived from The Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). In addition, this paper presents a previously unreported case of a CaHA-associated vascular complication. Results: There were 32 articles describing 42 cases, plus our case included in this review. There were 15 cases of vision complications, 23 cases of non-vision complications, and 5 experimental studies. The most common injection sites reported were nasal region for vision complications (45%) and nasolabial folds for non-vision complications (40%). Of the 38 human cases, the most prevalent treatment choice was steroids (24 cases, 63%). Complete or near complete improvement was reported in 83% of non-vision complications and 40% of vision complications. There was no noticeable homogeneity in the management strategies and outcomes of the patients. Of the 5 experimental studies, no clear consensus on treatments was found. Conclusion: Vascular complications of CaHA are seemingly uncommon, but it is widely suspected that this is due to underreporting. While best management is prevention, preparation for a potential complication is equally important. Derived from CaHA literature, hyaluronic acid filler complication protocols, findings of this review, and personal experiences, this report proposes management strategies for CaHA-associated vascular complications. We hope these strategies provide a much-needed framework for injectors to refer to and utilize as needed.

Standardized approach to treatment of retinal artery occlusion after intraarterial injection of soft tissue fillers: EYE-CODE

Inadvertent intraarterial injection of soft tissue fillers during facial aesthetic procedures can result in serious adverse events including visual impairment and blindness. Once the retinal artery has been occluded, only a short window of opportunity exists before blindness becomes irreversible. All physicians should be prepared for the eventuality of intraarterial injection, despite its rarity. The aim of this document is to provide a simple and evidence-based protocol using the easy to remember acronym EYE-CODE: EYE (I call retinal referral center), C (check vision), O (optic nerve function), D (decrease intraocular pressure), and E (erase filler). The EYE-CODE acronym incorporates 2 key components: (1) a systematic office-based protocol to first determine whether vision loss is present and to what extent and (2) a treatment strategy that can be started in the acute office setting and continued by an emergency ophthalmologist. The protocol incorporates a crash kit of treatments readily available to an aesthetic physician combining measures to rapidly reduce intraocular pressure to allow the emboli to dislodge downstream with measures to improve retinal perfusion. EYE-CODE provides an up-to-date, one-stop reference for appropriate management of retinal artery occlusion induced by injection of soft tissue fillers.

Endovascular management of critical hand ischemia by 'palmar arch loop' technique.

Critical hand ischemia with advancing gangrene of digits requires urgent intervention to salvage as much tissue as possible. The purpose of this study was to evaluate the efficacy of "palmar arch loop" technique for endovascular management of critical hand ischemia by establishing inline flow to the palmar arch via both radial artery and ulnar artery, in patients with failed antegrade recanalization. To the best of our knowledge, this is the first case series evaluating the efficacy of "palmar arch loop" technique, with retrograde percutaneous transluminal angioplasty of the involved radial artery and/or ulnar artery. We retrospectively investigated 10 patients (60% female; mean age 42 ± 18 years; mean time of presentation post-acute event 24 ± 11 days) with critical hand ischemia undergoing endovascular intervention using "palmar arch loop" technique at a single center in northern India between April 2017 and March 2019. All patients were followed up at regular intervals (weekly for a month, fortnightly for 3 months, and then at 6 and 12 months) with clinical assessment and SpO2 measurement. Study end points were technical success rate, hand healing, and primary patency rate at one year. Causes for critical hand ischemia were iatrogenic injuries due to inadvertent intra-arterial injection in 50% (n = 5) and thromboembolic events in 50% patients (n = 5). Vessels involved were: both radial artery and ulnar artery along with the PA in 50%; radial artery and palmar arch in 30%; ulnar artery and palmar arch in 20%. All of them had total occlusion of the involved vessel (>2/3rd of total length) with occlusion/diffuse disease of palmar arch as well; 70% technical success rate was achieved ensuring inflow to palmar arch via both the arteries with improved flow distally to the common and proper digital arteries. Retrograde percutaneous transluminal angioplasty of radial artery in 50% (n = 5) and ulnar artery in 20% (n = 2) was done successfully by looping the guidewire across the palmar arch; 90% showed subjective improvement in pain with healing of the lesions and/or formation of clear line of demarcation with reversal of pregangrenous changes proximally. Out of the eight patients with gangrene of fingers, three underwent minor amputation of the gangrenous digits and five underwent auto-amputation of the gangrenous tissue with complete healing of the stump. Primary patency rate was 85.7% at one year. There was no access site-related complication or mortality in the follow-up period. Endovascular management of critical hand ischemia by "palmar arch loop" technique is an efficient technique to deal with occluded forearm vessels, particularly when antegrade recanalization fails. This technique, with good technical success and patency rates, is potentially a unique tool in the endovascular armamentarium for salvaging hand.

The safety and efficiency of performing cervical transforaminal epidural steroid injections under fluoroscopic control on an ambulatory/outpatient basis

PurposeCervical transforaminal epidural steroid injections (CTFESIs) have become an increasingly utilised means of treating radicular pain over recent decades, although a number of reports have brought their safety into question. Much of this has been attributed to the use of particulate steroids and the theoretical risk of embolic complications with inadvertent intra-arterial injection. This study documents the complications encountered at our centre when performing CTFESI over a more than 10-year study period with predominant use of particulate steroid. Our procedural technique is also described. This study aims to highlight the importance of operator technique first and foremost and how, with safe and reproducible technique that confidently avoids intra-arterial injection, CTFESI can be performed safely irrespective of the choice of steroid.MethodsAll patients undergoing CTFESI between January 2008 and August 2018 at our centre were prospectively recruited to the study, documenting total number of injections/procedures per patient, presence of/description of complications and severity and type of steroid administered.ResultsFive hundred and twenty-seven patients underwent 1047 procedures (1753 individual cervical levels injected) over the study period: 1011 procedures performed with particulate steroid (triamcinolone acetonide) and 36 performed with non-particulate (dexamethasone). Only six complications were encountered, all spontaneously self-resolving without intervention and considered minor (grade 1).ConclusionsWith fastidious safe technique, CTFESI can be safe, efficacious and cost-effectively administered on an outpatient basis. Predominant use of particulate steroids did not lead to any significant complications.Graphic abstractThese slides can be retrieved under Electronic Supplementary Material.

Effective Rejuvenation with Hyaluronic Acid Fillers: Current Advanced Concepts.

After studying this article, the participant should be able to: 1. Process several patient-specific factors before reaching an optimal treatment strategy with appreciation for facial balance. 2. Define the advantages and disadvantages of various hyaluronic acid preparations and delivery techniques, to achieve a specific goal. 3. Perform advanced facial rejuvenation techniques adapted to each facial zone, combining safety considerations. 4. Prevent and treat complications caused by inadvertent intraarterial injections of hyaluronic acid. The growing sophistication and diversity of modern hyaluronic acid fillers combined with an increased understanding of various delivery techniques has allowed injectable filler rejuvenation to become a customizable instrument offering a variety of different ways to improve the face: volume restoration, contouring, balancing, and feature positioning/shaping-beyond simply fading skin creases. As more advanced applications for hyaluronic acid facial rejuvenation are incorporated into practice, an increased understanding of injection anatomy is important to optimize patient safety.

The Role of Anastomotic Vessels in Controlling Tissue Viability and Defining Tissue Necrosis with Special Reference to Complications following Injection of Hyaluronic Acid Fillers.

Most target areas for facial volumization procedures relate to the anatomical location of the facial or ophthalmic artery. Occasionally, inadvertent injection of hyaluronic acid filler into the arterial circulation occurs and, unrecognized, is irreparably associated with disastrous vascular complications. Of note, the site of complications, irrespective of the injection site, is similar, and falls into only five areas of the face, all within the functional angiosome of the facial or ophthalmic artery. Retrospective and prospective studies were performed to assess the site and behavior of anastomotic vessels connecting the angiosomes of the face and their possible involvement in the pathogenesis of tissue necrosis. In vivo studies of pig and rabbit, and archival human total body and prospective selective lead oxide injections of the head and neck, were analyzed. Results were compared with documented patterns of necrosis following inadvertent hyaluronic acid intraarterial or intravenous injection. Studies showed that the location of true and choke anastomoses connecting the facial artery with neighboring angiosomes predicted the tissue at risk of necrosis following inadvertent intraarterial hyaluronic acid injection. Complications related to hyaluronic acid injections are intimately associated with (1) the anatomical distribution of true and choke anastomoses connecting the facial artery to neighboring ophthalmic and maxillary angiosomes where choke vessels define the boundary of necrosis of an involved artery but true anastomoses allow free passage to a remote site; or possibly (2) retrograde perfusion of hyaluronic acid into avalvular facial veins, especially in the periorbital region, and thereby the ophthalmic vein, cavernous sinus, and brain.

Ischemic Hand Complications From Intra-Arterial Injection of Sublingual Buprenorphine/Naloxone Among Patients With Opioid Dependency.

Sublingual buprenorphine/naloxone, a common treatment for opioid dependence, is frequently abused by intravenous injection. Inadvertent intra-arterial injection of buprenorphine/naloxone can produce acute ischemic insult to the hand due to gelatin embolism. Our purpose was to review a series of these patients in order to describe the clinical entity, review the outcomes, and propose a rational treatment algorithm. Clinical records of all patients evaluated by the hand surgery team between 2011 and 2015 for ischemia of the hand after buprenorphine/naloxone injection were reviewed. Treatment, complications, and amount of tissue loss were recorded. Patients presenting within 48 hours of the injection were treated with intravenous heparin for 5 days, followed by oral aspirin and clopidogrel for 30 days. Those presenting after 48 hours were treated with aspirin and clopidogrel only. Ten patients presented during the review period. Average follow-up time was 13 weeks. Eight had ischemia of the radial side of the hand, 1 of the ulnar side, and 1 had bilateral ischemia. Three patients were treated with intravenous heparin and 5 with oral agents. Two presented with dry gangrene and did not receive anticoagulation. All patients experienced tissue loss. There was no difference in outcome regardless of treatment. With the increasing use of sublingual buprenorphine/naloxone in opioid dependency, ischemic hand injuries will be seen with greater frequency. Whereas outcomes did not vary with treatment modality in this series, further study is needed to determine the most effective treatment of these injuries.

Case report: Inadvertent intra-arterial injection during sclerotherapy may not be the disaster you think

Inadvertent intra-arterial injection is a rare and serious complication of sclerotherapy. Multiple treatments have been used in reported cases, with varying levels of success. We report a rare case of intra-arterial injection being treated with steroids and pulsed dye laser therapy and present a plan for future incidences. A 52-year-old woman presented to the clinic looking for aesthetic improvement to telangiectatic veins on the anterior aspect of the right leg. She developed cutaneous necrosis after sclerotherapy injection with 4 mL of 0.5% liquid polidocanol. After 23 months of pulsed dye laser therapy and a course of oral prednisolone, the patient made a good recovery and is left with minimal lasting tissue damage. More research is needed into the area of treating cutaneous necrosis with a pulsed dye laser, but this case report indicates a possible future therapeutic use after a successful outcome.

Inadvertent Intra-Arterial Drug Injections in the Upper Extremity: Systematic Review

To review the literature pertaining to inadvertent intra-arterial drug injection in the upper extremity, explore the various treatment options and their outcomes, and identify risk factors for limb amputation following intra-arterial injection. A systematic review of Medline, EMBASE, and Cochrane databases (inception to March 2013) was completed for patients presenting with intra-arterial drug injection of the upper extremity. Details on intervention and outcome were extracted and subjected to pooled analysis with amputation as the primary outcome. A total of 25 articles (209 patients) were included for review. Mean patient age was 31 ± 8 years (male, 71%; female, 29%). Prescription opioids (33%) were the most commonly injected substance, and the brachial artery (39%) was the most common site. The overall weighted mean amputation incidence was 29%. Anticoagulants were the most common treatment used (77%). From pooled analysis, conditions requiring antibiotic use were significantly associated with a higher incidence of amputation; whereas use of steroids was associated with a lower incidence of amputation. Patients presenting 14 hours or more after injection and those injecting crushed pills rather than pure substances had significantly higher incidences of amputation. Intra-arterial drug injection of the upper extremity carries an amputation incidence of nearly 30%. Conditions requiring adjunctive antibiotic use and delay in receiving care were both significantly associated with higher incidences of amputation. No single treatment protocol to date has established superiority. Therapeutic IV.

Accidental Intra Arterial Injection of Ephedrine: What about the Treatment with Nitroglycerin?

Accidental intra-arterial (IA) injection of drugs in the perioperative setting is fortunately a rare event, but it can cause severe extremity ischaemia, which can result in significant morbidity due to tissue necrosis. There have been many articles reported about inadvertent intra-arterial injections of various drugs over the last decades. However, we found none about the unintentional IA injection of ephedrine, so we present the following case.

Inadvertent Intra-arterial Injection of 123I-MIBG in a Patient With Metastatic Pheochromocytoma

We present an interesting image of the inadvertent arterial injection of I-MIBG (metaiodobenzylguanidine) in a 36-year-old man with hereditary, metastatic pheochromocytoma, who underwent a diagnostic whole-body scan for the evaluation of extent of disease before possible I-MIBG therapy. During the tracer injection in the left antecubital area, the patient experienced tingling and skin redness in the left forearm and hand.

Intravascular Flow Detection During Transforaminal Epidural Injections: A Prospective Assessment

Background: Transforaminal epidural steroid injections (TFESI) are a mainstay in the treatment of spine pain. Though this commonly performed procedure is generally felt to be safe, devastating complications following inadvertent intra-arterial injections of particulate steroid have been reported. The use of digital subtraction angiography (DSA) has been suggested as a means of detecting intra-arterial needle placements prior to medication injection. Objective: To examine the efficacy of DSA in detecting intra-arterial needle placements during TFESI. Study Design: Prospective cohort study evaluating the impact of DSA on detecting intra-arterial needle placements during TFESI. Methods: We enrolled 150 consecutive patients presenting to a university-affiliated spine center with discogenic and/or radicular symptoms affecting the cervical, lumbar, and sacral regions. For each injection, prior to imaging with DSA, traditional methods for vascular penetration detection were employed, including the identification of blood in the needle hub (flash), negative aspiration of blood prior to injection, and live fluoroscopic injection of contrast. Once these tests were performed and negative for signs of intra-arterial needle placement, DSA imaging was utilized prior to medication administration for identification of vascular flow. Results: A total number of 222 TFESI were performed, 41 injections at the cervical levels (18.47%), 113 at the lumbar levels (50.9%), and 68 at the sacral levels (30.36%). Flash was observed in 13 injections performed (5.85% of the total number of injections): one (0.45%) in the cervical, 2 (0.9%) in the lumbar, and 10 (4.5%) in the sacral levels. In 11 TFESI blood aspiration was obtained (4.95% of all injections): 3 (1.3%) in cervical, 4 (1.8%) in lumbar, and 4 (1.8%) in sacral injections. Live fluoroscopy during contrast injection detected 46 (20.72%) intravascular flow patterns: 7 (3.1%) cervical, 17 (7.6%) lumbar, and 22 (9.9%) sacral. DSA identified an additional 5 intravascular injections after all previous steps had resulted in negative vascular penetration signs, which accounted for 2.25% of all injections. Limitations: This is a prospective, single-center study with a relatively small number of patients and no control group. Conclusion: DSA detected additional 5.26% intravascular needle placements following traditional methods. Our findings also support other studies that conclude TFESI are generally a safe procedure. We recommend that special attention should be paid to the sacral injections as vascular penetration was statistically higher than at other levels. Key words: Digital subtraction angiography, transforaminal epidural steroid injections

Introducing an arterial non-injectable connector into clinical practice

The standard arterial system for blood withdrawal provides no impediment to intra-arterial injection [1] and bacterial contamination. We assessed the probability of inadvertent intra-arterial injection, transmission of bacterial contamination and surveyed the nursing staff following introduction of a non-injectable connector (NIC).

Good Clinical Outcome After Accidental Intra-arterial Injection of Flunitrazepam Tablets in 16 Drug Abusers with Critical Limb Ischaemia

Inadvertent intra-arterial injection of flunitrazepam tablets intended for intravenous use by drug abusers has devastating effects. We report here on the clinical outcome of 16 drug abusers developing critical limb ischaemia after flunitrazepam injection. Treatment combined immediate analgesia and anticoagulation, long-lasting local thrombolysis and vasodilatation, antibiotic prophylaxis, and physical mobilization. The immediate bolus injection of 5,000 IU heparin was followed by a continuous heparin infusion up to the target partial thromboplastin time. Under arteriographic control local intra-arterial infusion with alternating 4-h cycles of 5 mg recombinant tissue plasminogen activator followed by 5 μg prostaglandinE1 (PGE1) was performed for 24-48 hours. Subsequently, 60 μg PGE1 was applied once daily. Drug abusers, having been injected with 4-30 mg flunitrazepam, were treated 3-72 hours after the accident, with six of them not being treated until after 24 hours. All showed a high tissue ischaemia score. At the time of being discharged from hospital 13 patients had a normal extremity. In one patient, first receiving treatment 72 hours after injection, minor amputation of fingers was necessary. The life of the patient who injected 30 mg flunitrazepam in the leg was saved after hip disarticulation. One patient developed neurological dysfunction in the affected toes. Intensive treatment after inadvertent intra-arterial drug injection normalized the affected extremity in most drug abusers, even after the late onset of therapy.