Plastic Cannula Research Articles

Effect of Early Cannulation with Plastic Cannula on Arteriovenous Fistula Patency in Hemodialysis Patients

Introduction: Plastic cannulas have been used to cannulate arteriovenous fistulas (AVFs) for hemodialysis (HD) in Japan for many years. However, the effect of early cannulation with plastic cannulas on AVF patency is not known. Objective: We analyzed the relationship between first cannulation time (FCT) and patency rates for AVFs cannulated with plastic cannulas and investigated whether early cannulation with plastic cannulas affects AVF patency. Methods: In total, 122 patients who underwent primary AVF construction were divided into an early cannulation group (FCT <10 days) and a late cannulation group (FCT ≥10 days). The Kaplan-Meier method and multivariable Cox regression models were used to investigate AVF patency. Results: Median FCT was 6 days. There was no statistically significant between-group difference in primary (p = 0.643) or secondary (p = 0.453) patency rates. Early or late cannulation was not significantly associated with primary patency (hazard ratio [HR] 1.21; 95% CI 0.71–2.05) or secondary patency (HR 0.46; 95% CI 0.08–2.77) after adjustment for age, sex, presence of diabetes mellitus or hypertension, and HD at baseline. Conclusions: Early AVF cannulation (<10 days from creation) with plastic cannulas does not affect access patency, and it may be possible to cannulate AVFs earlier than 10 days to decrease the need for use of a central venous catheter.

Adjustable and Rigid Fixation of Brain Tissue Oxygenation Probe (Licox) in Neurosurgery: From Bench to Bedside

Multimodal neuromonitoring has become a fundamental part of management for many neurosurgical disorders such as subarachnoid hemorrhage and severe traumatic brain injury. Brain tissue oxygen tension monitoring requires insertion of a probe into the brain parenchyma through a single multiple lumen bolt, or in a subcutaneously tunneled fashion. As those patients often require early magnetic resonance imaging, typically using bolts is disadvantageous due to massive metal artifact. Similarly, subcutaneous tunneling is often problematic as suture fixation can loosen over time. We hereby report a new method of fixation of the Licox brain tissue oxygenation probe with 1 or 2 3-way taps that are attached to a standard plastic cannula, resulting in a stable connection with no need for further direct sutures around the probe and above all with no metal artifacts, which negates magnetic resonance imaging. The extended fixation system was first tested with cardiopulmonary resuscitation in a brain injured porcine model. It was thereafter adopted in our daily clinical practice.

Beyond the bedside.

His small body lies there. Limp. Lifeless. Limbs assume a flopped out, semi-flexed position, without strength to resist the pull of gravity below. His fontanelle, normally flush with the surrounding skull, creates a diamond-shaped depression at his vertex. Skin, doughy from lack of fluid hardly retracts when I pinch it between my two fingers. His small heart beats vigorously. Half-closed, sunken eyes show he is fast losing a desperate fight for life. He has a name, but it could be Deng, or Lual, or Dut, such is the frequency we see patients in this condition. His family have travelled by foot from a village several hours away. They have come late. Almost too late. His peripheries are cold, blood vessels constricted in an effort to maintain perfusion to his vital organs. Tourniquet-ed limbs are pulled into position seeking a small vein. He bears several puncture marks over his scalp. But there is not enough blood flowing to feed the small plastic cannula that could save his life. We have no time. He barely flinches as I drive a large needle through his skin and into the bone in his leg. Pushing and twisting until a ‘pop’ indicates that I am in the marrow below. Fluid flows through bone into venous tributaries to feed his thirsty tissues. Several hours later, he shows signs of improvement – his eyes start to glisten, he stirs when he is handled, his skin and lips appear plumper. His heart has slowed. A bag of fluid has saved his life. Six years later, I still often think of the Dengs and the Duts. They have defined my career path – from the remote, dusty walls of our hospital in South Sudan to our Paris-based Médecins Sans Frontières (MSF) headquarters. Every year 5.9 million children under 5 die.1 Over half of hospital deaths occur within 24 h of admission, highlighting the importance of rapid, effective evaluation and treatment.2 Most of these deaths could be averted with simple, affordable interventions: in the case of Deng, a bag of fluid to treat hypovolaemic shock. But getting the right treatment to the right person at the right time requires functioning systems, co-ordinated logistics and trained health personnel – often severely lacking in the settings in which MSF works. Caring for a critically ill child requires a holistic approach, evaluating and responding to all needs with the available resources and contextual constraints. The majority of those working in our projects are national staff and investing in their professional development is crucial to improve patient outcomes. Standardised trainings based on locally relevant guidelines provide consistency, increase staff capacity and improve standards of care. The MSF Paediatric Emergency Hospital Care course was first introduced last year. Throughout 5 days of exercises, case studies, skills stations and simulations, it is a joy to witness participants expand their knowledge as nurse–doctor teams work together to manage their patients. In the process, I am a facilitator rather than instructor (Figs 1, 2). They learn from me, but – more importantly – they learn from each other, and from themselves. By fostering a culture of construction, rather than instruction, this process continues beyond the training as they pass on their new skills and knowledge to their colleagues. After all, it is they who will be looking after Deng long after I am gone.

Computational Fluid Dynamic Analysis of the Hemodialysis Plastic Cannula.

The jet of fluid returning to the patient through a hemodialysis venous needle has previously been reported as a potential source of endothelial damage which can lead to intimal hyperplasia (IH) in arteriovenous fistulae (AVF). Metal needles are the current standard practice for accessing the vascular system in hemodialysis. However, plastic cannulae have been used in Japan for 30 years. This study utilized computational fluid dynamics to analyze the hemodynamics of blood exiting a plastic cannula and determined the optimal placement and blood flow rate. Transient simulations were run using a 15G Argyle Safety Fistula Cannula with Anti-Reflux Valve inserted into an idealized cephalic vein. The cannula tip was fixed at three different locations within the vein (upper third, middle, and lower third) with blood flow rates of 200 mL/min, 300 mL/min, and 400 mL/min imposed. The high degree of jet break down immediately after exiting the cannula was attributed to the staggered side hole arrangement, position of the cannula in the vein, and the imposed blood flow rate. Elevated levels of wall shear stress which may lead to IH were identified at the site of jet impingement on the vein floor as well as regions of high residency time. The risk of IH may be minimized by enhancing the breakdown of the jet through the use of optimal blood flow rates between 300 and 400 mL/min and ensuring the cannula tip is placed away from the walls of the vein.

Plastic Cannula use in Hemodialysis Access

Successful cannulation of arteriovenous fistula (AVF) or arteriovenous graft (AVG) is an important concept in hemodialysis. Metal needles have been used for cannulation in dialysis for over 50 years. Plastic cannula for dialysis is currently being introduced into Australia. To identify if the implementation of plastic cannula could decrease the amount of miscannulations and adverse events in AVFs at first cannulation. Train all staff in the Barwon Health renal department in the new technique of plastic cannula insertion and implement a new protocol for cannulation of AVFs in the first two weeks of dialysis. The training process took 12 months longer than anticipated due to issues with 'expert' to 'novice' reservations from staff, but initial results are positive with the statewide key performance indicator of new patients using AVF at first dialysis rising from 50% in 2013 to 78% in 2015. Staff were significantly more successful cannulating with plastic cannula in patients who had AVF only (67% success) than those who had a CVC alternative (24% success). Plastic cannulas offer a new and innovative way to cannulate AVFs and with time, expertise and training can be utilized to provide a successful cannulation program for patients starting hemodialysis with AVFs.

Evaluation of a modified in-plane ultrasound technique for routine arterial catheterisation

Evaluation of a modified in-plane ultrasound technique for routine arterial catheterisation

Critérios clínicos utilizados por profissionais para liberação de dieta via oral em pacientes adultos hospitalizados

Resumo:OBJETIVO:identificar critérios clínicos utilizados por profissionais para liberação de alimentação via oral em pacientes hospitalizados que apresentam risco para disfagia.MÉTODOS:participaram do estudo 48 profissionais que atuam em dois hospitais gerais de uma cidade do interior do Paraná. Os dados foram coletados por meio da aplicação de um questionário.RESULTADOS:100% dos profissionais consideram o nível de consciência importante para a deglutição, apenas 52,2% vê a importância da presença de deglutição salivar antes que se inicie via oral. Destes, 95,8% elencam Acidente vascular cerebral e Traumatismo cranioencefálico como principais doenças relacionadas a disfagia, porém nenhum apontou a Doença Pulmonar Obstrutiva Crônica. Além disso, somente 47,9% reconhecem a importância da avaliação fonoaudiológica após extubação orotraqueal independente do motivo da intubação ou patologia de base. E, 45,8% considera necessária oclusão do orifício da traqueostomia no momento da oferta alimentar, mostrando que não fazem a relação entre fisiologia da deglutição e uso da traqueostomia. Sobre alimentar um paciente com cânula plástica e balonete insuflado, 52,1% dos profissionais consideram ser possível e 47,9% dizem que não. Observa-se que 77,1% dos profissionais considera que a retirada da traqueostomia melhora e facilita o processo de deglutição, sendo este um percentual estatisticamente significante.CONCLUSÃO:há um conhecimento regular dos profissionais sobre o manejo das disfagias em âmbito hospitalar. Verifica-se a necessidade de um programa de formação continuada a equipe para melhoria do atendimento de pacientes disfágicos.

PWE-235 Long term subcutaneous saline and magnesium administration in patients with a short bowel. 10 year outcomes

<h3>Introduction</h3> Subcutaneous administration of water, sodium and magnesium is a treatment for patients with a short bowel and an adequate nutritional status, but with sodium and magnesium depletion. This study aimed to determine the long-term outcomes of patients treated with subcutaneous fluid (SCF). <h3>Method</h3> 10 year retrospective review of medical, dietetic and pharmacy records of patients identified as receiving home SCF administration from an ‘Intestinal Failure’ database. All patients selected had had an inpatient assessment in which bowel function was optimised and a subcutaneous regimen established. All patients were taught to self-administer fluids via gravity through a 22 Gauge plastic cannula inserted prior to each infusion into the subcutaneous tissue of the upper leg or abdomen. Patients were reviewed 3–6 monthly. <h3>Results</h3> 26 patients (19F:7M) were identified). Mean BMI 23.1 ± 4.7 (18.1–41.4). Mean time receiving SCF was 22 ± 34 (0.5–139) months. Underlying condition was Crohn–s/ulcerative colitis (n = 10), surgical complications (n = 8), mesenteric infarction (n = 5), other (n = 3). Mean infusion volume was 4 ± 2.1 (0.5–7) litre/week. 4(15%) patients had &lt;100cm small bowel to stoma, mean duration of SCF was 11 ± 6.9 (3–18) months. 9 (35%) patients had 100–150cm small bowel to stoma, mean duration 16 ± 23 (2–74) months. 11(42%) patients had more than 150cm small bowel to stoma, mean duration 32 ± 47 (0.5–139) months. 2(8%) patients had small bowel to colon, mean duration 19.5 ± 2.1 (18–21) months. There was no difference between patients with &lt;150cm small bowel vs those with &gt;150cm, p = 0.25. 21(81%) patients had magnesium in their infusions, mean 21 ± 9.8 (8–40) mmol per week; 16(76%) having 4mmol and 5(24%) having 8mmol per infusion. Patients on 4mmol magnesium were on treatment 17.4 ± 34 (3–139) months, those on 8mmol 10 ± 8.5 (2–24) months. The difference between these was not significant p = 0.4. Most patients 20(77%) had no complications. 5(19%) patients had leaking at the infusion site after a mean time of 50 ± 56 (8–139) months. Failure of treatment was most commonly due to an infusion taking too long to go in (more than 14 h ± fluid leaking (n = 6). In 2 patients the treatment did not correct magnesium, 2 patients had weight loss requiring parenteral nutrition. 6 patients stopped after corrective surgery. 2 patients were transferred elsewhere. 8 patients are still on treatment. <h3>Conclusion</h3> SCF are well tolerated in patients with a short bowel and sodium and magnesium depletion. Most patients continue with no complications for more than a year. Stopping SCF did not relate to small bowel length or the presence of magnesium but most commonly to the failure of the subcutaneous tissues to accept the infusion fluid. <h3>Disclosure of interest</h3> None Declared.

Surgical importance of arterial segments of human kidneys: an angiography and corrosion cast study.

Variations in the arterial supply of human kidney have been observed frequently, either in routine dissections or surgical practice. The main objective of the present study was to describe the arterial segmental pattern of human kidneys and its variation by angiography and corrosion cast techniques. Forty kidneys were washed and a plastic cannula was inserted into renal artery and the omnipaque dye was injected into it and X-ray was taken. The corrosion casts were prepared by injecting coloured acetate butyrate (CAB) granules solution. Five vascular segments of kidney were seen based on the branching pattern of the renal artery by angiography and corrosion cast techniques. The renal artery was divided into anterior and posterior branches. The anterior branch further divided into four branches viz. apical segmental artery (ASA), Upper segmental artery (USA), middle segmental artery (MSA), lower segmental artery (LSA) while the posterior branch continue as posterior segmental artery. The origins of segmental arteries were variable. In 60% cases apical segmental artery (ASA) had common origin with upper segmental artery (USA) while in 40% cases it took origin directly from the main renal artery. Similarly the variations in the origin of the other branches of anterior division of renal artery were observed. The posterior segmental artery (PSA) however was single and comparatively small and supplied the posterior surface of the kidney. The knowledge of the vascular pattern of the kidney is thus important for the purpose of angiography and surgical procedures especially for nephrectomy and kidney transplantation.

Broken Tip of Karman Cannula Removed at Hysteroscopy

gled cutting loop. A 22-year-old woman underwent suction curettage of a missed abortion at 6 weeks of gestation. The tip of the Karman cannula, a 6-mm flexible plastic cannula, broke during the procedure. After multiple unsuccessful attempts to remove the cannula tip via mechanical means under ultrasound guidance, the patient was ultimately referred to us for hysteroscopic intervention. Hysteroscopic view from

Long-term results of probing guided with soft cannula in children with congenital nasolacrimal duct obstruction

To report the results of soft probing in children with congenital nasolacrimal duct obstruction (CNLDO). A prospective, non-randomised interventional study included 158 eyes of 122 children aged 2 months-5 years, with CNLDO. A plastic intravenous catheter sheath supported intraluminally with a guiding metal probe was introduced through the superior canaliculus. During intubation, the plastic cannula was gently introduced through the nasolacrimal system, while the metal probe inside was withdrawn concurrently. After the complete withdrawal of the metal probe, the duct was irrigated with a high pressure saline solution through the plastic cannula. Once the obstruction was totally dissolved and a patent passage was observed, the plastic cannula was withdrawn and the procedure was completed with a nasolacrimal lavage with a gentamycin and dexamethasone combination. Clinically successful results were achieved in 142 eyes (89.8 %). No significant complications occured intraoperatively or postoperatively. In children under age 5, our technique has a high success rate with no significant complications. This method allows probing in a more controlled way. This method may be particularly suitable for surgeons during training, when the most false lumen formation is observed.

Migration of Bakri balloon through an unsuspected uterine perforation during the treatment of secondary postpartum hemorrhage

The current case describes an unreported complication of Bakri balloon placement: the migration of the Bakri balloon to the broad ligament through an unsuspected uterine rupture. Finally, a hysterectomy had been required. The Bakri balloon may be involuntary introduced in an unexpected uterine rupture, even if the balloon is placed with ultrasound guidance.

Cannot cannulate

Cannot cannulate

A healthy volunteer study to investigate trace element contamination of blood samples by stainless steel venepuncture needles

Context. The trace elements cobalt (Co), chromium (Cr), manganese (Mn) and nickel (Ni) are normally present at low concentrations in blood. There has been a concern that stainless steel venepuncture needles typically used for collection of blood samples may contaminate these samples, leading to the masking of deficiency states or causing potential clinical confusion as to whether an individual has a “toxic” concentration. Objective. To determine whether there is any difference between the concentrations of the trace elements obtained by different methods of blood sampling. Methods. We took blood samples using a standard venepuncture needle, a “butterfly” winged infusion needle (three consecutive samples) and a plastic intravenous cannula (three consecutive samples) from 10 healthy volunteers. We measured the concentrations of Co, Cr, Mn and Ni in the samples using Inductively Coupled Plasma Mass Spectrometry, and used analysis of variance (ANOVA) to investigate if there was any difference between the methods of blood sampling. Results. The mean ± standard deviation blood metal concentrations were: Co 0.33 ± 0.2 μg/l, Cr 2.43 ± 1.55 μg/l, Mn 8.07 ± 7.74 μg/l and Ni 10.4 ± 4.69 μg/l. There was considerable variation between blood metal concentrations of individual subjects and a few sporadic high values. By ANOVA, there was no significant difference between the metal concentrations measured using different methods of blood collection. Conclusions. It is not necessary to routinely use a plastic cannula for blood sampling for trace element analysis. However, it is possible that sporadic contamination due to stainless steel needles may occur, so we would recommend that unexpected high concentrations are verified by taking a second sample taken through a plastic cannula.

Direct Aspiration Endometrial Biopsy Via Flexible Hysteroscopy

Direct Aspiration Endometrial Biopsy Via Flexible Hysteroscopy

Management of Seroma Drainage in the Community: A Further Technique for Complicated Cases

Sir: Seroma formation after lymph node surgery is an all-too-frequent complication. Management options that have included quilting sutures, suction drainage, and fibrin glue have all been associated with morbidity and lengthy hospital stays. An innovative option for the treatment of freely draining seromas was reported in a past issue of Plastic and Reconstructive Surgery, describing the simple use of a stoma bag placed over the area to aid drainage and provide a means of controlled drainage that is able to be applied, changed, and completely managed in the community.1 We have found this technique to be highly useful in this setting of seromas that are freely draining, and sought the benefit of an adjunctive technique for closed, nondraining seromas. We have since expanded the applicability of this “stoma-bag” technique to more complicated scenarios. Although closed seromas are widely treated with inpatient drainage, we describe a technique for community or outpatient drainage to aid the application of a stoma bag for drainage. The technique requires little more than a sterile environment and a disposable intravenous cannula. Under aseptic technique, a 21-gauge intravenous cannula is passed through the skin into the seroma cavity, until flashback of fluid is seen. The needle introducer is removed and the plastic cannula is left in situ for ongoing drainage. A stoma bag is placed over the cannula to collect fluid according to the previously reported technique (Fig. 1). Simple dressings can hold the cannula in place or sutures can be used if preferred.Fig. 1.: Freely draining axillary seroma, with a 21-gauge plastic cannula having been passed through the skin into the seroma cavity, and a stoma bag placed over the cannula for ongoing drainage.We have used this technique in a range of clinical settings, including seromas accumulating after lymphadenectomy, sentinel node biopsy, large flap donor or recipient sites, and other surgically created cavities. The technique is of particular utility where there is a negative-pressure dressing applied to a wound but where an adjacent cavity is not drained by the suction dressing: in such a setting, the negative-pressure dressing can remain in situ without loss of vacuum seal. The stoma bag technique is thus applicable to a range of clinical scenarios, without necessitating open drainage and its associated morbidity, operating room access, or inpatient stay. Shivam Kapila, B.Sc., M.B.B.S., M.S. Warren M. Rozen, M.B.B.S., B.Med.Sc., Ph.D. Felix C. Behan, M.B.B.S. Department of Plastic and Reconstructive Surgery Peter MacCallum Cancer Center East Melbourne, Victoria, Australia DISCLOSURE The authors declare have no financial interest to declare in relation to the content of this article. No outside funding was received.

Technical innovation: Wire guided ductography

To introduce an easy and improved technique for performing ductography using inexpensive easily available intravenous cannula. Guide wire: Prolene/Surgipro 3-0 (Polypropylene mono filament non-absorbable surgical suture). A plastic 26 G intravenous cannula. Disposable syringe 2 ml. Non-ionic contrast (low density like Omnipaque 240 mg I/I). The guide wire (Prolene 3-0) is introduced into the orifice of the duct heaving discharge and 26 G intravenous plastic cannula is then passed over the guide wire. The cannula is advanced in the duct over guide wire by spinning around it. When the cannula is in place the guide wire is removed. Any air bubbles present in the hub of the cannula can be displaced by filling the hub from bottom upwards with needle attached to contrast filled syringe. 0.2-0.4 ml non-ionic contrast is gently injected. Injection is stopped if the patient has pain or burning. Magnified cranio-caudal view is obtained with cannula tapped in place and gentle compression is applied with the patient sitting. If duct filling is satisfactory a 90* lateral view is obtained. A successful adaptation of the technique for performing ductography is presented. The materials required for the technique are easily available in most radiology departments and are inexpensive, thus making the procedure comfortable for the patient and radiologist with considerable cost effectiveness.

A durable repair of a broken silastic catheter using a topical skin adhesive

A break in the external portion of a tunneled silastic catheter due to wear is a frequent event. We describe an easy yet durable fix for catheters with a break on the external portion of the catheter. The repair is achieved by cutting the catheter proximal to the breakage point and attaching with a topical skin adhesive, a readily available blunt metal or plastic cannula.

Emergency cricothyrotomy in infants – evaluation of a novel device in an animal model

According to different algorithms of airway management, emergency cricothyrotomy is the final step in managing an otherwise not accessible airway. As an alternative to an open surgical procedure, minimally invasive approaches exist. Quicktrach baby™ is a commercially available set for a minimal invasive cricothyrotomy in infants. The set consists of a plastic cannula over a metal needle for direct placement in the trachea. So far, this device has not been evaluated for its intended use. We hypothesize that Quicktrach baby™ allows the establishment of an emergency airway. The aim was to prove that the device is easy to handle and the cricothyrotomy fast to perform. After approval of the local ethics committee, the study was performed on the cadavers of 10 adult rabbits. Cricothyrotomy was performed with Quicktrach baby™. Successful placement, performance time, and complication rate were documented. Possible ventilation with a breathing bag was evaluated. Data are reported as mean and interquartile range. Successful placement of Quicktrach baby™ was possible in all attempts. The placement took 31 [23-43] s. In two cases, a fracture of the cricoid's cartilage was seen. In one animal, damage to the posterior wall mucosa was observed. In all cases, sufficient ventilation was possible. Quicktrach™ baby proved to be a reliable technique. In the animal model, it is easy and fast to perform. Only a few minor complications occurred. Sufficient ventilation was possible in all attempts.

Evaluation of Gadodiamide Versus Gadobutrol for Contrast-Enhanced MR Imaging in a Rat Brain Glioma Model at 1.5 and 3 T

To compare equivalently-dosed (0.1 mmol/kg) gadobutrol (Gadovist) and gadodiamide (Omniscan) in a rat brain glioma model with respect to lesion signal-to-noise (SNR), contrast-to-noise (CNR), and contrast enhancement (CE) at 1.5 and 3 T. Lesion enhancement with standard-dose gadobutrol in scans performed at 1.5 T was also compared with that of half-dose gadobutrol in scans performed at 3 T. Fifty-four rats were injected with glioma cells via a plastic brain cannula and divided into 3 groups. In the first group, each animal was studied using gadodiamide and gadobutrol, with 24 hours separating injections. The 2 agents were administered in random order at a dose of 0.1 mmol/kg. Each animal was scanned using a 3 T MR system. The procedure for the second group was similar, but scanning was performed at 1.5 T. For the third group, rats were given standard or half-dose gadobutrol and scanned at 1.5 and 3 T, respectively. For all MR examinations, T1-weighted images were obtained precontrast and at 1, 3, 5, 7, and 9 minutes postcontrast administration. At 3 T improvements in SNR, CNR, and CE with gadobutrol ranged from 11.8% to 16.0%, 30.5% to 35.4%, and 27.1% to 31.5%, respectively, and at 1.5 T from 7.0% to 11.1%, 27.1% to 35.8%, and 23.8% to 29.5%, respectively. Differences between these parameters with gadobutrol and gadodiamide were statistically significant (P < 0.0001-0.05) at all time points following contrast administration. In group 3, no significant differences in CNR or CE were found between full dose gadobutrol at 1.5 T and half-dose at 3 T, although SNR was significantly greater (28.5%-35.1%; P < 0.0008) at 3 T. Gadobutrol (Gadovist) demonstrates superior lesion enhancement to equivalently-dosed gadodiamide (Omniscan) in the rat brain glioma model. These results are complemented by the improved observed and theoretical safety profile of the first agent, in particular with regard to nephrogenic systemic fibrosis. The ability to image with half-dose gadobutrol at 3 T without a statistically significant decrease in lesion enhancement, compared with 1.5 T, offers an additional theoretical safety margin and potential cost-savings.