The learning curve for ultrasound-guided peripheral intravenous cannulation in adults: a multicenter study

Aims: To lower the threshold for applying ultrasound (US) guidance during peripheral intravenous cannulation, nurses need to be trained and gain experience in using this technique. The primary outcome was to quantify the number of procedures novices require to perform before competency in US-guided peripheral intravenous cannulation was achieved. Materials and methods: A multicenter prospective observational study, divided into two phases after a theoretical training session: a hands-on training session and a supervised life-case training session. The number of US-guided peripheral intravenous cannulations a participant needed to perform in the life-case setting to become competent was the outcome of interest. Cusum analysis was used to determine the learning curve of each individual participant. Results: Forty-nine practitioners participated and performed 1855 procedures. First attempt cannulation success was 73% during the first procedure, but increased to 98% on the fortieth attempt (p<0.001). The overall first attempt success rate during this study was 93%. The cusum learning curve for each practitioner showed that a mean number of 34 procedures was required to achieve competency. Time needed to perform a procedure successfully decreased when more experience was achieved by the practitioner, from 14±3 minutes on first proce-dure to 3±1 minutes during the fortieth procedure (p<0.001). Conclusions: Competency in US-guided peripheral intravenous cannulation can be gained after following a fixed educational curriculum, resulting in an increased first attempt cannulation success as the number of performed procedures increased.

Comparison of Bolus and Continuous Infusion of Adrenocorticotropic Hormone During Adrenal Vein Sampling

BackgroundAdrenocorticotropic hormone (ACTH) is widely used in adrenal vein sampling (AVS) and can be administered as a bolus injection or continuous infusion. The optimal administration method has not been determined. We aimed to compare the effects of ACTH bolus with infusion on cannulation success, lateralization assessment and adverse events (AEs).MethodsRetrospectively collected data from patients with primary aldosteronism who underwent AVS with ACTH at a tertiary hospital in China. Rate of successful cannulation, lateralization index (LI), complete biochemical remission and AEs related to AVS were analyzed.ResultsThe study included 80 patients receiving ACTH bolus and 94 receiving infusions. The rate of successful cannulation was comparable between bolus and infusion groups (75/80, 93.4% vs 88/94, 93.6%). In those with successful cannulation, the bolus group had a higher selectivity index than the infusion group, while LI [6.4(1.8-17.5) vs. 7.6(2.0-27.8), P=0.48] and rate of complete biochemical remission (43/44, 97.7% vs 53/53, 100%, P=0.45) did not significantly differ between the two groups. One in the bolus and one patient in the infusion group had adrenal vein rupture but they recovered with conservative treatment. The bolus group reported more transient AEs such as palpitation (52.9% vs 2.2%) and abdominal discomfort (40.0% vs 2.2%) than the infusion group.ConclusionsDue to their similar effects on cannulation success and lateralization, but a lower rate of transient AEs in the infusion group, the continuous infusion method should be recommended for ACTH stimulation in AVS.

Performing central venous catheters in neonates and small infants undergoing cardiac surgery using a wireless transducer for ultrasound guidance: a prospective, observational pilot study

Background Neonates and small infants with congenital cardiac disease undergoing cardiac surgery represent major challenges facing paediatric anaesthesia and perioperative medicine. Aims. We here aimed to investigate the success rates in performing ultrasound (US) guided central venous catheter insertion (CVC) in neonates and small infants undergoing cardiac surgery, and to evaluate the practicability and feasibility of thereby using a novel wireless US transducer (WUST). Methods Thirty neonates and small infants with a maximum body weight of 10 kg and need for CVC before cardiac surgery were included in this observational trial and were subdivided into two groups according to their weight: < 5 kg and ≥ 5 kg. Cannulation success, failure rate, essential procedure related time periods, and complications were recorded and the clinical utility of the WUST was assessed by a 5-point Likert scale. Results In total, CVC-insertion was successful in 27 (90%) of the patients and the first attempt was successful in 24 (78%) of patients. Success rates of CVC were 80% < 5 kg and 100% ≥5 kg. Comparing the two groups we found a clear trend towards longer needle insertion time in patients weighing < 5 kg (33 [28–69] vs. 24 [15–37]s, P = .07), whereas, the total time for catheter insertion and the duration of the whole procedure were similar in both groups (199 [167–228] vs. 178 [138–234] and 720[538–818] vs. 660 [562–833]s. In total, we report 3 (10%) cases of local hematoma as procedure-related complications. Assessments of the WUST revealed very good survey results for all parameters of practicability and handling (all ratings between 4.5 and 5.0). Conclusion Although difficulties in CVC-placement seem to relate to vessel size and patient’s weight, US guided CVC-insertion represents a valuable, fast, and safe intervention in neonates and small children undergoing cardiac surgery. Using the WUST is feasible for this clinical application and may aid in efforts aiming to optimize perioperative care. Trial registration Wireless US-guided CVC placement in infants; Clinicaltrials.gov: NCT04597021; Date of Registration: 21October, 2020; retrospectively registered.

Difficult Biliary Cannulation in Endoscopic Retrograde Cholangiopancreatography: An Overview of Advanced Techniques

Endoscopic retrograde cholangiopancreatography (ERCP) plays a significant role in the treatment of a vast array of pancreatobiliary diseases. However, despite significant progress in the optimisation of ERCP methods and accessories, the technical and clinical success of ERCP can vary significantly due to a variety of patient and operator factors. Over the past several decades, a number of advanced techniques have been developed to improve cannulation success rates, including the use of double-guidewire, pancreatic duct accessory-assisted, precut, and rendezvous techniques. Here, the authors provide an update and overview of the existing advanced techniques used in cases of difficult biliary cannulation, as well as the approach to their selection.

Application of Precut Papillotomy in Patients With Surgically Altered Gastrointestinal Anatomy

It is challenging to perform ERCP (endoscopic retrograde cholangiopancreatography) in patients with surgically altered gastrointestinal anatomy. The failure rate of selective bile duct cannulation by the standard method is high. To explore the application of precut papillotomy (PP) technique in patients with gastrectomy, we carried out this retrospective analysis. From January 2017 to September 2020, 107 patients with surgically altered gastrointestinal anatomy were referred to our department for ERCP examination. Among them, 11 cases were duodenal stricture or jejunal stricture, resulting in the inability to reach the duodenal papilla. Eleven patients stopped cannulation because they could not tolerate the further operation. 60 patients were intubated successfully by standard method. Finally, 25 patients using the precut papillotomy technique were included in our analysis. Of the 25 patients who used pp, 21 completed selective biliary cannulation, with a success rate of 84% (21/25). Compared with standard intubation, the PP technique increased the success rate of intubation in patients with altered anatomy by 21.9%. Among the patients we included, 2 cases had adverse events, including 1 case of acute pancreatitis and 1 case of perforation; the incidence of adverse events was 8%. All adverse events were mild and cured after conservative treatment. In patients with gastrointestinal anatomical changes, PP is effective and relatively safe to improve the selective biliary cannulation success rate.

Vein cannulation success rates by German paramedics: a single-centre study

Introduction: Gaining intravenous (IV) access is vulnerable to errors and failure, and this study analysed IV procedures by paramedics in the federal state of Hesse in Germany to examine these. Methods: This was a single-centre, observational, pilot study survey on gaining vascular access. As well as identifying the success and failure rate of IV attempts, factors associated with a higher risk of failure were analysed using logistic regression, Χ2 or Fisher's exact test. Results: A total of 207 vascular access attempts were included in the analysis, of which 90.34% were successful. Significantly associated with higher risk of failure were patients' age (OR 1.05; 95% (CI 1.02–1.10); p=0.041), or when two (OR 3.94; 95% CI (2.39–6.20); p≤0.001) or more than three attempts (OR: 3.26 [95% CI: 1.35; 5.17]; p=0.003) were needed rather than one. In contrast, risk of failure was significantly lower when patients indicate a good (OR 0.02; 95% CI (0.00–0.15); p≤0.001) or moderate (OR 0.04 (95% CI 0.01–0.17); p≤0.001) vein status compared to a bad vein status. Failure rates were higher when paramedics were working a night shift (OR 0.06; 95% CI (0.00–0.98); p=0.005) rather then during the day. Conclusion: A proportion of IV access attempts by paramedics are unsuccessful and, if paramedics are to provide invasive interventions, non-IV options for drug administration should be available.

The impact of the catheter to vein ratio on peripheral intravenous cannulation success, a post-hoc analyses

Background Intravenous cannulation is usually the first procedure performed in modern healthcare, although establishing peripheral intravenous access is challenging in some patients. The impact of the ratio between venous diameter and the size of the inserted catheter (catheter to vein ratio, CVR) on the first attempt success rate can be of added value in clinical. This study tries to give insight into the consideration that must be made when selecting the target vein and the type of catheter, and proved the null hypothesis that an optimal CVR would not be associated with increased first attempt cannulation success. Methods This was a post-hoc analyses on adult patients admitted for peripheral intravenous cannulation. Intravenous cannulation was performed according to practice guidelines, by applying the traditional landmark approach. The CVR was calculated afterwards for each individual patient by dividing the external diameter of the inserted catheter by the diameter of the target vein, which was multiplied by 100%. Results In total, 610 patients were included. The median CVR was 0.39 (0.15) in patients with a successful first attempt, whereas patients with an unsuccessful first attempt had a median CVR of 0.55 (0.20) (P<0.001). The optimal cut-off point of the CVR was 0.41. First attempt cannulation was successful in 92% of patients with a CVR<0.41, whereas as those with a CVR>0.41 had a first attempt success rate of 65% (P<0.001). Conclusion This first introduction of the CVR in relation to cannulation success should be further investigated. Although, measuring the venous diameter or detection of a vein with a specific diameter prior to cannulation may increase first attempt cannulation success.

Utility of Plasma Metanephrines in Adrenal Venous Sampling in Primary Aldosteronism

Introduction: Adrenal Venous Sampling (AVS) is the most reliable means of identifying surgically curable subtypes of primary aldosteronism (PA). Cortisol levels are used to determine cannulation success and lateralization. However, cortisol has a variable secretion pattern and long-half life, and can be co-secreted by adrenal adenomas, leading to misinterpretation of results. Plasma metanephrines (MN) are a possible alternative analyte. MN levels are unaffected by stress, have a short half-life of 3–6 minutes and are released continuously by the adrenals, resulting in very high concentration gradients between the adrenal veins (AV) and peripheral veins (PV), thus providing a sensitive means to determine cannulation success. Premise:The objective of this study was to see if MN can be used in lieu of cortisol in AVS. A secondary end-point was to see if the data was particularly useful in patients who are known co-secretors of cortisol. Methods: Data from AVS carried out without cosyntropin stimulation, from October 2018 to March 2020, were analysed retrospectively. Of these, 51 had additional samples drawn for MN at the time of the procedure and were recruited. Six patients were identified as having autonomous cortisol secretion as they failed an overnight dexamethasone suppression test (ONDST). The data was analysed using cortisol and MN separately and then compared with regards to their selectivity and lateralization index. Data was also analysed to see if known co-secretors had an elevated cortisol/MN ratio of more than 2 on the affected side as described in previous papers. Results: When compared to cannulation and lateralization outcomes using cortisol, similar results were obtained using, a MN AV/PV ratio of more than 12 to indicate successful cannulation and an aldosterone/MN ratios of greater than 5 to confirm lateralization. Contralateral suppression to less than 0.5 for aldosterone/MN below the PV was seen in unilateral disease. With regards to the six co-secretors, all had elevated cortisol/MN ratios of more than 2 on the affected side. Three had concordant results but the other three had discrepant results, with MN analysis suggesting unilateral disease and cortisol measurements suggesting bilateral disease. Two had undergone surgery with biopsy confirming unilateral disease that correlated with MN analysis. The third is under medical management. Conclusion: This is the first study evaluating the use of MN to determine lateralisation of aldosterone production in PA. Further studies are needed, but using MN may be a more reliable alternative to cortisol in the analysis of AVS before definitive surgery in particular in patients with cortisol co-secretion.

Comparison of three different techniques for internal jugular vein cannulation under real time ultrasound guidance

<p><strong>Background: </strong>Ultrasound (USG) guided Internal jugular venous (IJV) cannulation is preferred than traditional approach due to increase in success rate, reduction in time taken and attempts of successful cannulation and less complications. The purpose of our study was to observe and compare three different real time 2-dimensional US-guided approaches and to determine which approach improves rate of successful cannulation, decreases complications along with shorter average time taken for the procedure. Primary outcomes of the study were venous access time, catheterization time and success rate. Secondary outcomes were number of patients requiring second attempt and complications observed.</p><p><strong>Methods: </strong>120 adult patients were randomly divided into three groups according to real time US guided cannulation done with SAX-OP approach, LAX-IP approach and OAX-IP approach. Parameters like venous access time, catheterization time, number of patients requiring second attempt and complications were noted.</p><p><strong>Results: </strong>Venous access time was shortest in LAX group 21.84±3.67 seconds which was just significant statistically. Catheterization time was shortest in LAX group 241±123 seconds. Cannulation success rate was highest in LAX group 98% and was statistically significant. Patients requiring second attempt was least in LAX group 2.5%. Posterior IJV wall puncture was observed in 10% patients in SAX group and none in LAX and OAX group which was statistically significant.</p><p><strong>Conclusions:</strong> LAX-IP showed better performance in terms of higher cannulation success, lesser average venous access time and catheterization time and lesser complications. On toggling USG probe, both IJV and carotid artery can be differentiated and carotid puncture could be avoided. Hence LAX approach is safer and effective approach.</p>