Traditional Landmark Approach Research Articles

The anatomical location of the great saphenous vein at the thigh and ankle: a neonatal cadaver study

Providing critically ill neonatal patients with parenteral nutrition, medication, fluids, and access to blood sampling is essential in intensive care units. One option for blood sampling is the great saphenous vein within the proximal thigh, and near the medial malleolus in neonates via ‘conventional’ landmark and ultrasound techniques. Practitioners in many countries still use the traditional landmark approach to locate the great saphenous vein in neonates, regardless of access to ultrasound. We aim to provide measurements that accurately describe the anatomy of the great saphenous vein in neonates to aid in cannulation success. The great saphenous vein was exposed in the proximal thigh and near the medial malleolus by reflecting the skin in 31 and 30 formalin-fixed neonate cadavers, respectively. Pins were placed at essential bony landmarks and soft tissue structures. The termination of the great saphenous vein within the proximal thigh can be located 6.8 ± 1.5 mm inferior to the inguinal ligament. The average shortest distance from the medial malleolus to the great saphenous vein was 4.3 mm, 2.0 mm anterior, and 3.1 mm superiorly. The diameter of the great saphenous vein in the proximal thigh and at the medial malleolus ranged between 1.4 mm and 1.6 mm, and 0.9 mm and 1.1 mm, respectively with a 95% confidence level. Our results provide a more accurate description to gain venous access through the great saphenous vein. However, if available, ultrasound should be used to locate and confirm the diameter of the great saphenous vein in the lower limb.

A Prospective Cohort Study to Evaluate Needle Passes Using a Portable Ultrasound Device versus Traditional Landmark Approach for Epidural Anesthesia in a Busy Obstetric Tertiary Care Center

Despite its many cited benefits, ultrasound guidance for neuraxial procedures is not widespread in anesthesiology. Some cited limitations include device cost and accessibility. We test the hypothesis that a handheld and relatively inexpensive ultrasound can improve neuraxial proficiency (e.g., decreased needle manipulations and block time). This prospective study compared the number of needle passes, redirections, and procedural time between epidural placed with a handheld ultrasound versus landmarks. Needle passes and attempts were defined as the number of times the Tuhoy needle was redirected, and the times skin was punctured (re-insertion). Procedural time was defined as the time from local anesthetic infiltration until loss of resistance was obtained. The impact of level of training and accuracy of the device were also analyzed. 302 patients receiving labor epidural were included in the study. No difference in body mass index (BMI) nor distribution of level of training was noted between the groups. Regression analysis adjusted for BMI demonstrated a decrease in needle passes (-1.75 (95% CI -2.62, -0.89), p < 0.001), needle attempts (-0.51 (95% CI -0.97, -0.04), p = 0.032) and procedural time (-154.67s 95% CI -303.49s, -5.85s), p = 0.042) when a handheld ultrasound was utilized. The mean (95% Confidence interval) difference between needle depth and ultrasound depth was 0.39 cm (0.32, 0.46), p < 0.001. The use of a handheld device resulted in statistically significant decrease of needle manipulations and block time. More research is needed to evaluate the impact of and increase in accessibility of ultrasound technology.

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

BackgroundIntravenous 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.MethodsThis 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%.ResultsIn 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).ConclusionThis 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.

Ultrasound-Guided Cannulation: Time to Bring Subclavian Central Lines Back.

Despite multiple advantages, subclavian vein (SCV) cannulation via the traditional landmark approach has become less used in comparison to ultrasound (US) guided internal jugular catheterization due to a higher rate of mechanical complications. A growing body of evidence indicates that SCV catheterization with real-time US guidance can be accomplished safely and efficiently. While several cannulation approaches with real-time US guidance have been described, available literature suggests that the infraclavicular, longitudinal “in-plane” technique may be preferred. This approach allows for direct visualization of needle advancement, which reduces risk of complications and improves successful placement. Infraclavicular SCV cannulation requires simultaneous use of US during needle advancement, but for an inexperienced operator, it is more easily learned compared to the traditional landmark approach. In this article, we review the evidence supporting the use of US guidance for SCV catheterization and discuss technical aspects of the procedure itself.

Comparison of Ultrasound-Assisted and Classic Approaches to Continuous Paravertebral Block for Video-Assisted Thoracoscopic Surgery: a Prospective Randomized Trial

Background: Continuous paravertebral blocks (PVBs) are an established means of providing postoperative analgesia in thoracic surgery. While PVBs can be administered using multiple methods, no randomized clinical trial comparing the relative advantages of the ultrasound-assisted approach to the traditional landmark approach, the two most commonly-used approaches in our hospital, has been conducted to date. Our study thus sought to compare the efficacy of these two methods of PVB placement. Methods: From July 1, 2013 to June 5, 2014, 45 patients scheduled for thoracic surgery consented to participate in the study. Each patient was randomized into a group receiving PVB placed with either the classic landmark-based (CL) or ultrasound-assisted (US) approach. Each group received 20 ml of ropivacaine 0.5% as the local anesthetic (LA). Onset time and spread of the block were then assessed by a blind observer. The main outcome was hydromorphone consumption 24 hours after initiation of patient-controlled analgesia (PCA). Secondary outcomes were the following: Pain Numeric Rating Scale (NRS) score after 24 hours at rest and during deep inspiration; requested PCA boluses in 24 hours; total LA consumption and number of boluses through the catheter; and changes between pre-and post-operative (24 hours after surgery) tidal volume, forced vital capacity, forced expiatory volume in 1 sec, and peak expiatory flow. Results: Mean opiate consumption during the 24 hours after PCA initiation was 5.75 mg (4.23-7.26) for the CL group and 6.38 mg (4.51-8.25) for the US group (p= 0.643). None of the secondary outcomes statistically differed between the two groups. Conclusions: Our data supports the concept that choice of continuous PVB approach does not affect the outcome. The expertise of the anesthesiologist performing the block remains a key factor in choosing which approach to use.

Novel Educational Module for Subclavian Central Venous Catheter Insertion Using Real-Time Ultrasound Guidance

Given increasing evidence supporting a real-time ultrasound (US)-guided approach for subclavian vein (SCV) central venous catheter (CVC) insertion as compared with the traditional landmark approach, we sought to develop a standardized curriculum to offer healthcare providers a means to attain increased competency and confidence in US-guided SCV CVC insertion. Retrospective review of prospectively collected data. Single institution's American College of Surgeons Level 1 Accredited Education Institute within an academic tertiary care center. A total of 77 residents and midlevel providers working in our surgical intensive care unit. Providers participated in a tiered educational module designed to teach safe US-guided SCV CVC insertion. The education consisted of a multimedia didactic presentation and a hands-on simulation session, including US anatomy on live subjects and anatomical model-based SCV CVC insertion. Assessment of the effect of education included a written examination and confidence survey, administered pre- and postintervention, and videotaped simulation session graded by blinded expert evaluators. Of the 77 participants, 70 participants completed a posttest with a median 5-point increase in score compared with that of the pretest score (p < 0.0001). Confidence ratings based on a 5-point Likert scale demonstrated an increase in confidence in SCV CVC insertion (p < 0.0001), using the landmark approach (p < 0.0001), using US-guided approach (p < 0.0001), and in use of US to image the SCV (p < 0.0001). Postgraduate year-1 residents had lower mean global rating score (p = 0.010) than any other participants. This comprehensive hands-on teaching module-based curriculum enhanced learner knowledge of and confidence in US-guided SCV CVC insertion. This module can be implemented in simulation centers for teaching safe and successful SCV CVC insertion.

368 Sonographic Assessment of Inadvertent Vascular Puncture During Paracentesis Using the Traditional Landmark Approach

368 Sonographic Assessment of Inadvertent Vascular Puncture During Paracentesis Using the Traditional Landmark Approach

Using multiple timescale models for the evaluation of a time-dependent treatment.

In survival analysis, the absolute measure of cumulative risk provided by the Kaplan-Meier estimator is still the most used quantity for its easy calculation and direct interpretability. However, for describing the survival after an intervention that may occur at different times from baseline observation, the Kaplan-Meier estimator generally yields to biased results if intervention is considered as fixed at baseline. The main focus of the present paper is to extend the use of a multiple timescale model in the presence of a time dependent intervention. The aim is to obtain 1) an estimate of treatment effect in terms of hazard ratios by flexible modeling, 2) a valid prediction tool, i.e. estimate of prognosis for a patient who changes treatment later in time, and 3) an appropriate graphical representation of survival in the presence of a time dependent treatment change, accounting for different timescales. We will show the advantages of this approach on the comparison of chemotherapy versus transplant in children with high-risk acute lymphoblastic leukemia in first remission. We considered a model with two timescales that accounts for the change in treatment at different times in the disease course. An alternative approach to survival estimates is also proposed which has some advantages over the traditional landmark approach: it uses all the data available to plot survival from the date of remission, it avoids the arbitrary choice of a landmark time and explicitly models the change in hazard due to transplant.

Traditional landmark versus ultrasound guided tracheal puncture during percutaneous dilatational tracheostomy in adult intensive care patients: a randomised controlled trial.

IntroductionLong-term ventilated intensive care patients frequently require tracheostomy. Although overall risks are low, serious immediate and late complications still arise. Real-time ultrasound guidance has been proposed to decrease complications and improve the accuracy of the tracheal puncture. We aimed to compare the procedural safety and efficacy of real-time ultrasound guidance with the traditional landmark approach during percutaneous dilatational tracheostomy (PDT).MethodsA total of 50 patients undergoing PDT for clinical indications were randomly assigned, after obtaining informed consent, to have the tracheal puncture procedure carried out using either traditional anatomical landmarks or real-time ultrasound guidance. Puncture position was recorded via bronchoscopy. Blinded assessors determined in a standardised fashion the deviation of the puncture off midline and whether appropriate longitudinal position between the first and fourth tracheal rings was achieved. Procedural safety and efficacy data, including complications and number of puncture attempts required, were collected.ResultsIn total, 47 data sets were evaluable. Real-time ultrasound guidance resulted in significantly more accurate tracheal puncture. Mean deviation from midline was 15 ± 3° versus 35 ± 5° (P = 0.001). The proportion of appropriate punctures, defined a priori as 0 ± 30° from midline, was significantly higher: 20 (87%) of 23 versus 12 (50%) of 24 (RR = 1.74; 95% CI = 1.13 to 2.67; P = 0.006). First-pass success rate was 20 (87%) of 23 in the ultrasound group and 14 (58%) of 24 in the landmark group (RR = 1.49; 95% CI = 1.03 to 2.17; P = 0.028). The observed decrease in procedural complications was not statistically significant: 5 (22%) of 23 in the ultrasound group versus 9 (37%) of 24 in the landmark group (RR = 0.58; 95% CI = 0.23 to 1.47; P = 0.24).ConclusionsUltrasound guidance significantly improved the rate of first-pass puncture and puncture accuracy. Fewer procedural complications were observed; however, this did not reach statistical significance. These results support wider general use of real-time ultrasound guidance as an additional tool to improve PDT.Trial registrationAustralian New Zealand Clinical Trials Registry ID: ACTRN12611000237987 (registered 4 March 2011)Electronic supplementary materialThe online version of this article (doi:10.1186/s13054-014-0514-0) contains supplementary material, which is available to authorized users.

Systematic review: is real-time ultrasonic-guided central line placement by ED physicians more successful than the traditional landmark approach?

IntroductionThe superiority of ultrasonic-guided compared with landmark-guided central venous catheter (CVC) placement is not well documented in the Emergency Department.ObjectiveTo systematically review the literature comparing success rates between ultrasonic- and...

Systematic Review: Is Real-Time Ultrasonic-Guided Central Line Placement by ED Physicians more Successful Than the Traditional Landmark Approach?

Systematic Review: Is Real-Time Ultrasonic-Guided Central Line Placement by ED Physicians more Successful Than the Traditional Landmark Approach?

Comparison of Infection Rates Among Ultrasound-Guided Versus Traditionally Placed Peripheral Intravenous Lines

The purpose of this study was to compare infection rates of peripheral intravenous (IV) lines placed under ultrasound guidance with traditionally placed IV lines. We conducted a retrospective review of emergency department (ED) and hospital records of adult patients who had a peripheral IV line placed in the ED and were admitted to the hospital over a 1-year period. This study took place at a level I academic urban ED with an annual census of 75,000. All admitted patients with a peripheral IV placed under ultrasound guidance in the ED were identified. Control patients had a traditional landmark approach. Emergency department nurses followed standard aseptic precautions when inserting both ultrasound-guided as well as traditionally placed IV lines. Researchers reviewed all parts of the medical record, including ED and inpatient notes. Descriptive statistics and chi(2) and Fisher exact tests were used in data evaluation. A total of 402 patients who had peripheral IV lines placed under ultrasound guidance were compared with 402 matched control patients. In the ultrasound-guided IV group, the mean time between insertion to catheter removal was 2.6 days compared with 2.4 days in the traditional group (P = .03). There were 2 documented infections in the ultrasound group and 3 in the traditional group, yielding infection rates of 5.2 per 1000 in the ultrasound-guided IV group and 7.8 per 1000 in the traditional approach group. There was no statistically significant difference between infection rates in the two groups (P = .68). Both traditional and ultrasound-guided approaches had low infection rates, suggesting that there is no increased risk of infection with ultrasound guidance for peripheral IV lines.

Ultrasound-guided central venous access

Central venous catheterization is a critical component of management for the critically ill patient in the operating room and intensive care unit. When using ultrasound techniques for central venous access, access is achieved with fewer attempts, a reduced incidence of carotid artery punctures or ‘hits’, an increased success rate, and a decreased duration of procedure compared to the traditional landmark approach.

A survey of local opinion of NICE guidance on the use of ultrasound in the insertion of epidural catheters

In January, the National Institute for Health and Clinical Excellence (NICE) issued guidance on the use of ultrasound to facilitate catheterisation of the epidural space. In the published information, available to the public, the use of ultrasound compared with the ‘traditional landmark approach’ is quoted as being associated with fewer attempts, a decreased incidence of dural puncture and post procedure headache, and overall greater patient satisfaction [1]. These conclusions, which were based on obstetric and paediatric populations, and also on those requiring corrective back surgery, do not provide a balanced approach to the actual findings of the studies quoted. In two small studies involving neonates and children, there were no sound clinical end points that reached statistical significance [2, 3]. Further, we have reservations regarding the conclusions reached from the obstetric studies. In the three studies [4–6] where ultrasound was compared to a standard landmark technique (all cited from the same main author) there is no compelling statistical end point that favours the use of ultrasound. The decreased incidence of dural puncture quoted by NICE is based on two cases in the 150 control group (landmark) compared with one in the prepuncture ultrasound group. There are no statistical data for this [4]. In addition, whilst there were more cases of severe post-procedure headache in the control group (10% versus 2.7%) this actually grossly exceeds the number of dural punctures. Further, whilst ‘patient satisfaction with epidural space procedure’ was deemed to be higher in the ultrasound group, overall ‘patient satisfaction with general treatment’ was better in the control group. In pregnant women with a body mass index over 33 kg.m2, scoliosis, kyphosis, hyperlordosis or where there was anticipated difficulty in epidural insertion, fewer puncture attempts were required when ultrasound was used [5]. However, there were no recognised dural punctures in either group, and no statistical difference in failure rates or headaches. In a randomised control trial of 30 pregnant women comparing ultrasound and the landmark technique for the insertion of a combined spinal-epidural for Caesarean section, there was a significant reduction in the number of attempts using imaging. However, the success rate without ultrasound was unusually low, with 60% requiring more than one attempt [6]. We conducted a local email survey of anaesthetists in Wessex in light of these NICE guidelines. Of the 151 respondents, a 40% response rate, the majority being consultants, 97% have never used ultrasound to image the epidural space, although in the same geographical district it is common to use ultrasound both for regional anaesthesia and vascular access. Over 60% of respondents had received formal ultrasound teaching for the techniques that they used. In contrast, more than 90% were not aware of any courses that taught ultrasound techniques to identify the epidural space. Overwhelmingly, they concluded that without formal teaching, they would not find ultrasound guided epidural catheter insertion a useful technique. Ultrasound is an invaluable tool for anaesthetists both in vascular access and regional anaesthesia, its benefit in facilitating epidural catheter insertion is not demonstrated in the current literature referenced by the NICE guidelines. We agree that it has the potential to be a useful adjunct as a prepuncture method in those patients with difficult anatomical landmarks (obesity and back anomalies [7]). This will primarily be to obtain the level and estimated depth of the epidural space (accepting that some of the accuracy will be lost because of the probe compression, local anaesthetic infiltration and discrepancies in needle angle). In conclusion, there will need to be more evidence before most anaesthetists will be convinced of the usefulness of ultrasound for the placement of an epidural. The required infrastructure will need to be available before the NICE guidance can be adopted.

Sonographic guidance when using the right internal jugular vein for central vein access.

The intent of this study was to substantiate the advantages of the use of sonographic guidance for central venous access via the right internal jugular vein. Eighty sequential patients requiring central vein access were examined with a hand-held sonography transducer to determine the size, patency, and location of the right internal jugular vein before puncture. Access to the right internal jugular vein was subsequently performed, under sterile conditions, using sonographic guidance. Periprocedural complications were prospectively recorded. Subsequently, we compared our findings with published reports of complications when visible and palpable anatomic landmarks were used for guidance during cannulation of the internal jugular vein. Among these 80 patients, the anatomy of the right internal jugular vein was typical in only 57 (71%). In another 13 patients (16%), sonography showed a medial position of the right internal jugular vein, anterior to the common carotid artery. In three other patients (4%), the right internal jugular vein was positioned laterally by more than 1 cm. In the remaining seven patients (9%), the vein was thrombosed. Its diameter, measured without use of the Valsalva maneuver, also varied, measuring 0.5-2.0 cm. Cannulation was achieved in all 73 patients with a patent right internal jugular vein. One puncture was required in 68 patients (93%); two punctures in three other patients (4%); and three punctures in the remaining two patients (3%). In no case was the common carotid artery inadvertently punctured. Only one periprocedural complication occurred, and it was unrelated to the use of sonographic guidance. Sonographic guidance for central vein access via the right internal jugular vein is safer and more efficient than the traditional landmark approach.