This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Simhi, E. Articles by Katz, J. Search for Related Content PubMed PubMed Citation Articles by Simhi, E. Articles by Katz, J. Related Collections Ambulatory Pediatrics Technology

---

PEDIATRIC ANESTHESIOLOGY

A Vein Entry Indicator Device for Facilitating Peripheral Intravenous Cannulation in Children: A Prospective, Randomized, Controlled Trial

Eliahu Simhi, MD^*, Ludmyla Kachko, MD^*, Elhanan Bruckheimer, MD, and Jacob Katz, MD^*

From the *Department of Anesthesia, Schneider Children’s Medical Center of Israel, Petah Tiqwa and Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; Department of Anesthesiology and Critical Care Medicine, Children’s Hospital of Pittsburgh, Pittsburgh, Pennsylvania; and Department of Pediatric Cardiology, Schneider Children’s Medical Center of Israel, Petah Tiqwa and Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.

Address correspondence and reprint requests to Ludmyla Kachko, MD, Department of Anesthesia, Schneider Children’s Medical Center of Israel, 14 Kaplan Street, Petah Tiqwa 49202, Israel. Address e-mail to kachko_l{at}hotmail.com.

Abstract

BACKGROUND: Vascular access is often technically difficult in children because of the small caliber and impalpability of the veins. In this study, we sought to determine if use of the Vein Entry Indicator Device (VEID^TM) in children facilitates peripheral venous access.

METHODS: Two-hundred-two healthy (ASA grade I and II) children scheduled for same-day surgery at a major tertiary hospital in Israel were randomly allocated to undergo VEID-assisted or standard peripheral venous cannulation. All cases involved the insertion of a 22-gauge cannula into an upper limb vein. Primary outcome measures were number of attempts to successful cannulation, rate of success at first attempt, and time required for insertion. The data were presented as mean (sd). Analyses of variance and Pearson ² test or Fisher’s exact test were used to compare the groups; forward stepwise logistic regression was used to identify the three variables (age, vein assessment category, use of the VEID) significantly associated with a successful first attempt. A P value of 0.05 was considered significant.

RESULTS: Successful cannulation was achieved at the first attempt in the majority of patients in both groups. Two attempts were needed in 8% of the VEID group and 28% of the control group, and 3 attempts were needed in 1% and 3%, respectively (P < 0.01). Analysis by vein assessment category yielded a similar rate of successful first-attempt cannulations in the two groups for easy veins. However, for the difficult and intermediate categories, the rate was 89.7% in the VEID group compared to 23.3% in the control group (P < 0.001). The fewer number of attempts in the study group was associated with a shorter time from the start of the search for an appropriate vein to successful cannulation (9.1 s versus 22.5 s in the control group).

CONCLUSIONS: The VEID facilitates the insertion of peripheral venous cannulas in healthy children with intermediate/difficult veins undergoing same-day surgery, reducing the number of attempts and the overall time required.

Vascular access in infants and children can be technically challenging because of the small size of the veins and their location deep in the subcutaneous tissue which makes them difficult to palpate or visualize. The interventions currently in use in both routine and emergency settings to improve vascular access include local warming, transillumination, epidermal nitroglycerine, peripheral venous cutdown, ultrasonographic guidance, and intraosseous infusions. Nevertheless, in pediatric patients, the task of acquiring venous access often remains frustrating and time-consuming.

The Vein Entry Indicator Device (VEID; Vascular Technologies, Nes Ziona, Israel) was designed to facilitate peripheral IV cannulations (PIVC). The aim of the study was to evaluate its benefit in healthy children.

METHODS

Patients
The study group included otherwise healthy children aged 3 mo to 17 yr, with an ASA physical status I or II, who were scheduled for elective same-day surgery at a major tertiary pediatric medical center. Written informed consent was obtained from the parent(s) or legal guardian of all participants. Exclusion criteria were: need for emergency surgery, evidence of infection or congenital malformations at the place of puncture, in situ IV catheter, and parental refusal.

Study Design
The Ethics Committee of Schneider Children’s Medical Center of Israel approved the study protocol. The patients were randomly divided into two groups according to the last digit of their 9-digit identification number (issued to all residents in the country): patients with an odd number were allocated to undergo PIVC with the VEID, and patients with an even number were allocated to undergo standard PIVC. In all cases, a 22 gauge cannula was inserted into an upper limb vein. Background data (age, weight) were derived from the medical files. One senior pediatric anesthesiologist evaluated the veins, a second performed the cannulation, and a third recorded the results. Primary outcome measures for the study were number of attempts required for cannulation, rate of success at first attempt, and total time required for cannulation.

Vein Entry Indicator Device
VEID (Vascular Technologies, Nes Ziona, Israel) is designed to facilitate PIVC. The VEID is composed of a small plastic box containing a pressure sensor, processing unit, signal generator, and battery (Fig. 1) that is attached via an adapter to the distal end of the IV cannula after removing the flashback chamber cap. It can be used with any IV cannula that has a standard (female) Luer connection. The technical specifications of the device are presented in Table 1. The VEID is automatically activated on correct attachment to the cannula. After it identifies a change in pressure in the needle, indicating penetration of the vessel and entry of blood into the needle, it emits a continuous beep in <0.1 s reducing the likelihood of exiting the back wall of the vein. The beeping continues until the catheter is fully inserted and the needle is removed. If the needle punctures the distal wall during the procedure, the device identifies the decrease in pressure and the beeping stops, warning the clinician to reposition the cannula. Complete filling of the flash chamber does not affect the performance of the VEID. On completion of the procedure, the stylet and adapter are detached and discarded. The prototype used in the present study is safe for repeated application because the adapter prevents the sensor unit from contact with the blood. Disposable single-use VEID has since become available as well. The VEID has been approved by the Israel Ministry of Health (501-0000) and by the United States Food and Drug Administration (K993995), and it has a safety certificate from the European Union (0473).

View larger version (41K): [in this window] [in a new window]   Figure 1. Vein Entry Indicator Device (VEID). VA = VEID adapter.

Procedure
After preanesthesia evaluation and premedication with oral midazolam 0.5 mg/kg (maximum 15 mg), the patient was brought to the operating room. Using standard monitoring, anesthesia was induced via facemask with a halothane in oxygen/nitrous oxide 50% mixture. Before cannulation was attempted, a senior pediatric anesthesiologist who was blinded to the group allocation categorized the veins as follows: difficult (neither visible nor palpable), intermediate (barely visible and/or palpable), or easy (clearly visible and/or easily palpable). The same physician evaluated all patients. A second senior pediatric anesthesiologist, with experience of more than 15 yr in pediatric cannulation and several months in VEID use, performed all the cannulations. A 22-gauge, 25-mm long, IV cannula (BD Venflon, Becton Dickinson, Helsingborg, Sweden) was inserted into an upper limb vein in all patients.

A third pediatric anesthesiologist measured the time (in seconds) from the start of the search for an appropriate vein (after skin preparation and application of the tourniquet) to successful insertion of the cannula. Successful cannulation was confirmed by the absence of signs of infiltration after a crystalloid solution administration. The anesthesiologist also recorded the number of venipuncture attempts until successful cannulation. An attempt was defined as any withdrawal of the needle with a subsequent forward movement, regardless of whether a second skin puncture was performed. In both groups of patients, we ended the study after successful IV insertion.

Statistical Analysis
The data were analyzed with BMDP (BMDP Statistical Software1993. Chief Editor: W.J. Dixon, University of California Press, Los Angeles). Findings are presented as means and standard deviations in parenthesis. Continuous variables were compared using one-way and two-way analysis of variance. Log transformation was applied to data with a non-Gaussian distribution. Discrete variables were assessed with Pearson ² test or Fisher’s exact test, as appropriate. The dichotomous vein assessment (easy versus intermediate/difficult) was entered into the model as "0" for easy and "1" for "intermediate/difficult." Forward stepwise logistic regression model was used to identify the three variables (age, vein assessment category, use of the VEID) significantly associated with a successful first attempt. A P value of 0.05 was considered statistically significant.

RESULTS

The study sample included 202 patients (101 in the study group and 101 in the control group). Eight children were excluded before the randomization because their parents/guardians did not agree to participate in the study. There were no statistically significant differences in demographic data or vein assessment scores between the two groups (Table 2).

The mean time elapsed from the start of the search for an appropriate vein to successful cannulation was 9.1 s in the VEID group and 22.5 s in the control group (P = 0.003, Table 3). To determine the degree to which the vein assessment category contributed to this difference, we assessed each category separately. In patients with easy veins, the time needed for IV insertion was 7.5 s in the VEID group and 7.7 s in the control group. This difference was not statistically significant. However, in patients with intermediate veins, the time to successful cannulation was 6.4 s in the VEID groups and 46.1 s in the control group; corresponding values in patients with difficult veins were 22.2 s and 97.1 s. A Two-way analysis of variance applied to these data, showed a significant difference between VEID and control (P < 0.001) and significant effect of vein assessment on time reduction (P < 0.001). There was also a highly significant interaction (P < 0.001) between vein assessment categories and VEID/control groups (There was a major impact of the vein assessment in the control group, and a minor effect with the use of the VEID. The worst combination was difficult vein assessment without the use of the VEID, Table 3).

In the majority of patients, successful cannulation was achieved at the first attempt: 91% in the VEID group and 69% in the control group (P = NS). The maximum number of attempts was three in both groups. The average number of attempts per patient was 1.1 in the VEID group and 1.34 in the control group. Two attempts were required in 8% of patients in the VEID group and in 28% of the control group; 3 attempts were needed in 1% and 3% of the groups, respectively (P < 0.01).

By vein category, the success rate for first-attempt cannulation of the easy veins was similar in the VEID and control groups. Because of the small number of patients with intermediate (n = 35) and difficult veins (n = 7), these subgroups were combined for this analysis. We found that the rate of success at the first attempt was 89.7% (n = 35/39) in the VEID group compared to 23.3% (n = 7/31) in the control group (P < 0.001).

On stepwise logistic regression analysis to identify factors associated with the success of cannulation after a single attempt, the significant predictors were vein assessment category (easy versus not easy) (OR = 7.94, 95% CI, 3.28–19.1; P < 0.001), and use of the VEID (OR = 7.62, 95% CI, 2.92–19.9; P < 0.001). Patient age had no significant impact on successful IV insertion at the first attempt.

DISCUSSION

The present study demonstrated the effectiveness of the VEID in guiding vascular access before elective surgery in otherwise healthy children. PIVC are an essential part of anesthetics, and their early establishment provides a means for administering fluids and drugs. In children, because of their natural aversion to needles, anesthesia is usually administered by mask before cannulation. Nevertheless, PIVC insertion may still be difficult and time-consuming because the vessels in children are small and the percentage of subcutaneous fat may be high.1 Numerous previous venipunctures (for example, in preterm infants) pose additional difficulties. Moreover, success is often a function of practitioner experience and skill.2 A delay in PIVC may prolong the induction of anesthesia and can even be dangerous in the presence of complications, such as laryngospasm or hypotension.

The process of establishing IV access may be divided into two phases: locating the vein and inserting the catheter. Sometimes the first phase is accomplished on the basis of anatomical landmarks alone. Many techniques have been proposed in the literature to improve palpation or/and visualization of the target vein, such as tapping over the site, applying proximal tourniquets, local warming or having the arm hanging down.1,3–6 Transillumination with various devices has been used for many years in infants and neonates,7,8 and the application of glyceryl trinitrate ointment with a eutectic mixture of local anesthetics or after eutectic mixture of local anesthetics removal has been found to positively impact on venous dilation, choice of cannulation site, and ease of cannulation.9,10

Recent randomized clinical trials of more advanced technologies found ultrasound guidance to be effective in improving the success of PIVC in adults.11–14

The second phase of IV cannulation, insertion of the catheter, is more difficult to guide. The clinician identifies correct entry of the vein when he or she senses a "pop" or a change in resistance and observes blood at the back of the needle (flashback). This requires much experience and skill15 and is very difficult to teach. If the needle penetrates the back wall of the vein and the practitioner is now withdrawing the needle back, sensation can no longer serve as an indication for reentry. In addition, it takes time for the blood to enter the chamber; depending on the pressure in the vein and the size of the needle, the lag varies between 0.4 and 4.0 s (Table 4).

To the best of our knowledge, the VEID is the only currently available device for vein entry detection. An in vitro study used the Four-Vein Venipuncture Training Block Device (VATA, Canby, OR), which is equipped with an optical sensor and microphone, to compare the indication time between the VEID signal and visual flashback using different gauge needles (BD Venflon, Becton Dickinson, Helsingborg, Sweden). Entry into the blood vessel by the needletip triggered an oscilloscope signal. The findings are shown in Table 4 (Personal communication).

Chellia and Verghese16 evaluated the reliability of the VEID during peripheral vein cannulation in 52 patients aged 4 to 83 yr. However, they did not provide separate information for the pediatric patients. Their results suggested that the device could be useful for cannulation of difficult veins.

Not surprisingly, we found that the majority of our patients had easy veins, and successful cannulation was achieved at the first attempt in a major proportion of both the VEID and control groups. The VEID had a more important impact in the remaining children with intermediate and difficult veins, in whom the number of unsuccessful attempts was reduced threefold in the study group compared to controls, and the success rate for first attempts was increased fourfold. The difference in the number of attempts needed was associated with a shorter time required for the whole cannulation procedure.

We speculate that use of the VEID can at least partly eliminate both the strong dependence on practitioner skill inherent to the standard method for identifying the vessel and inserting the needle, and the use of flashback to indicate penetration, which can lead to error owing to the long lag time. Because of the continuous beep it emits, it can also help the clinician advance the needle, so that the catheter remains in the lumen of the vessel.

Our study was not designed to evaluate the learning curve either for the device or for PIVC, and the study has a few limitations.

Limitations of the Study

1. Although the study randomizes patients, blinding of the study was impossible.
   
2. A 22-gauge cannula was used in all patients, so we could not compare success rate by gauge size.
   
3. A third limitation is the low number of infants younger than 1 yr in the sample (4 in the control group and 10 in the study group).
   

CONCLUSION

The VEID facilitates the insertion of PIVC in healthy children with intermediate/difficult veins undergoing same-day surgery, reducing the number of attempts and the time required. We are not aware of any study that measured the success rate of PIVC under anesthesia in children. We had an overall 69% success rate in the control group with a very experienced pediatric anesthesiologist and we suspect that, with trainees, this rate might be even lower. We welcome any assistance devices in this under-studied area of pediatric anesthesia.

Footnotes

Accepted for publication June 19, 2008.

The device was provided by Vascular Technologies, Nes Ziona, Israel.

Drs. Simhi and Kachko contributed equally to this work.

REFERENCES

1. Haas NA. Clinical review: Vascular access for fluid infusion in children. Crit Care 2004;8:478–84[Web of Science][Medline]
2. Engum SA, Jeffries P, Fisher L. Intravenous catheter training system: computer-based education versus traditional learning methods. Am J Surg 2003;186:64–7
3. Mbamalu D, Banerjee A. Methods of obtaining peripheral venous access in difficult situations. Postgrad Med J 1999;75:459–62[Abstract/Free Full Text]
4. Roberge RJ. Venodilatation techniques to enhance venipuncture and intravenous cannulation. J Emerg Med 2004;27:69–73[Web of Science][Medline]
5. Lenhardt R, Seybold T, Kimberger O, Stoiser B, Sessler DI. Local warming and insertion of peripheral venous cannulas: single blinded prospective randomized controlled trial and single blinded randomized crossover trial. BMJ 2002;325:409–10[Abstract/Free Full Text]
6. Beer J. Local warming does help when inserting cannulas. BMJ 2002;325:1038[Free Full Text]
7. Bellotti GA, Bedford RF, Arnold WP. Fiberoptic transillumination for intravenous cannulation under general anesthesia. Anesth Analg 1981;60:348–51[Free Full Text]
8. Atalay H, Erbay H, Tomatir E, Serin S, Oner O. The use of transillumination for peripheral venous access in pediatric anesthesia. Eur J Anesthesia 2005;22:317–8
9. Teillol-Foo WL, Kassab JY. Topical glyceryl trinitrate and eutectic mixture of local anesthetics in children. A randomized controlled trial on choice of site and ease of venous cannulation. Anaesthesia 1991;46:881–4[Web of Science][Medline]
10. Andrew M, Barker D, Laing R. The use of glyceryl trinitrate ointment with EMLA cream for i.v. cannulation in children undergoing routine surgery. Anaesth Intensive Care 2002;30:321–5[Web of Science][Medline]
11. Keyes LE, Frazee BW, Snoey ER, Simon BC, Christy D. Ultrasound-guided brachial and basilic vein cannulation in emergency department patients with difficult intravenous access. Ann Emerg Med 1999;34:711–4[Web of Science][Medline]
12. Costantino TG, Parikh AK, Satz WA, Fojtik JP. Ultrasonography-guided peripheral intravenous access versus traditional approaches in patients with difficult intravenous access. Ann Emerg Med 2005;46:456–61[Web of Science][Medline]
13. Mills CN, Liebmann O, Stone MB, Frazee BW. Ultrasonographically guided insertion of a 15-cm catheter into the deep brachial or basilic vein in patients with difficult intravenous access. Ann Emerg Med 2007;50:68–72[Web of Science][Medline]
14. Schnadower D, Lin S, Perera P, Smerling A, Dayan P. A pilot study of ultrasound analysis before pediatric peripheral vein cannulation attempt. Acad Emerg Med 2007;14:483–5[Web of Science][Medline]
15. Treuren BC, Yusuf A, Galletly DC, Robinson BJ. A comparison of three ported cannulae available in New Zealand. Anaesth Intensive Care 1993;21:337–41[Web of Science][Medline]
16. Chelliah S, Verghese C. VEID. Vein entry indicator device. Anaesthesia 2000;55:195–6[Web of Science][Medline]

This article has been cited by other articles:

				A Novel Vein Entry Indicator Helps Pediatric IV Cannulation Journal Watch Emergency Medicine, December 5, 2008; 2008(1205): 3 - 3. [Full Text]

This Article Abstract Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Simhi, E. Articles by Katz, J. Search for Related Content PubMed PubMed Citation Articles by Simhi, E. Articles by Katz, J. Related Collections Ambulatory Pediatrics Technology