Arterial blood gas sampling“>American Journal of Emergency Medicine (2012) 30, 1100-1104

Original Contribution

Less painful arterial blood gas sampling using jet injection of 2% lidocaine: a randomized controlled clinical trial

Houman Hajiseyedjavady MD^a, Morteza Saeedi MD^a,?, Vahid Eslami^b,

Kavoos Shahsavarinia MD^c, Shervin Farahmand MD^d

^aEmergency Medicine Department, Shariati Hospital, Tehran University of Medical Science, Tehran, Iran

^bFaculty of Medicine, Tehran University of Medical Science, Tehran, Iran

^cEmergency Medicine Department, Imam Reza Hospital, Emergency Medicine of Tabriz University of Medical Science,

Tabriz, Iran

^dEmergency Medicine Department, Imam Khomeini Hospital, Tehran University of Medical Science, Tehran, Iran

Received 13 June 2011; revised 20 July 2011; accepted 21 July 2011

Abstract

Objective: The aim of this study was to compare pain levels from arterial blood gas sampling performed with or without application of lidocaine via jet injector.

Background: Pain is still a primary concern in the emergency department. Arterial blood gas sampling is a very painful procedure. No better technique for decreasing the pain of the ABG procedure has been presented. An ideal local anesthesia procedure for ABG sampling should be rapid, easily learned, inexpensive, and free of needlestick risk.

Materials and Methods: We evaluated the effectiveness of a lidocaine jet injection technique in achieving satisfactory pain control in patients undergoing ABG sampling. Forty-two patients were randomized to 2 groups: group A, which received lidocaine by jet injection (0.2 mL of lidocaine 2%), and group B, a control group that received a topical application of 1 mL of Lidocaine gel 2% 2 minutes before the ABG sampling. Pain was assessed on a 10-cm visual analog scale (0, absence of pain; 10, greatest imaginable pain).

Results: The pain visual analog scale score during ABG sampling was considerably lower in group A compared with group B (1.29 +- 0.90 vs 4.19 +- 1.43; P b .001). The number of attempts required for ABG sampling was significantly lower in group A compared with group B (1.29 +- 0.46 vs 2.1 +- 0.12; P = .009). All residents reported ease of use with the lidocaine jet injection procedure (P b .05).

Conclusion: Lidocaine jet injection provides beneficial and rapid anesthesia, resulting in less pain and a greater rate of successful ABG sampling. Therefore, it is recommended for use before ABG sampling to decrease the patient’s pain and the number of unsuccessful attempts and to enhance the patient’s satisfaction.

(C) 2012

Introduction

* Corresponding author. Tel.: +98 2166036585; fax: +98 4113352078.

E-mail address: [email protected] (M. Saeedi).

Although performing painful procedures is routine and unavoidable in an emergency department (ED) and many investigators have tried to find a solution to decrease the pain of

0735-6757/$ – see front matter (C) 2012 doi:10.1016/j.ajem.2011.07.011

patients in the ED, pain is still a main concern in the ED. In most situations and procedures, pain is not relieved system- atically and satisfactorily [1,2]. Two thirds of the trauma patients have moderate to severe pain at discharge [3]. Pain management is difficult, time-consuming, and expensive [4,5]. One of the most routine painful procedures in the ED is venous or arterial cannulation. Arterial blood gas sampling is a painful procedure because of high rates of failure involving several unsuccessful attempts before successful blood sam- pling. Another factor in the level of pain involved is the anatomical locations for ABG sampling in highly innervated places such as the wrist, elbow, or thigh. In most modern EDs, there is no protocol for local anesthetic medications before needle insertion, especially in adult patients. Therefore, it is understandable that we do not see any pain management attempts before ABG sampling even when there is a need for multiple attempts to perform the correct ABG sampling.

There are some limitations for choosing a method of pain control before cannulation. It should be fast, accurate, inexpensive and easily learned and nonpainful itself; however, no such advantageous technique has yet been presented for decreasing ABG pain. Some studies have reported the efficiency of the needle-free jet injector device in vaccinations, venous catheterization, and other adminis- trations [6-9]. Furthermore, jet injectors are widely used in local anesthesia for minor procedures and biopsies [10], digital blocks [11], and fine Needle aspirations [12]. The jet injector can be called a safe device because it does not contain any sharp components. Therefore, there is no threat of needlestick injury or any difficulty in discarding them. Moreover, because the jet injector has a disposable syringe, there is no concern about transmitting infection.

Studies have shown that injection of lidocaine via jet injector would provide more effective anesthesia compared with placebo injection via jet injector during needle insertion for peripheral intravenous cannula insertion [8,13,14]. Studies also have shown that anesthesia using a jet injector with lidocaine compared with other Topical anesthetics such as ELA-Max (since renamed LMX; Ferndale Laboratories, Ferndale, Michigan) [15] or eutectic mixture of local anesthesia (EMLA) [16] has a better or at least equal anesthesia effect for intravenous cannula insertion. No study has reported on the use of jet-injected lidocaine in patients undergoing ABG sampling. This study aimed to compare the pain level during ABG sampling in patients experiencing lidocaine injection using the jet injection device with that of patients receiving lidocaine gel before ABG sampling.

Methods

Study design

The study was conducted between June 2010 and January 2011 in the Imam-Reza Hospital in Tabriz, Iran, with local

research ethics committee approval and informed consent from the patients.

In our study, to ensure that the procedure was performed accurately, experienced postgraduate year-3 ED residents performed the ABG procedures and pain scoring. All scores were recorded separately and without having access to other scores. Pain score was measured at the end of the procedure by asking the patients about Pain severity using a visual pain score.

Grouping the patients was done randomly by using a number for each patient attending the ED. After grouping, attending physicians of the ED applied either 0.2 mL of lidocaine 2% via jet injector with a 2-cm distance from the skin and perpendicular to the site of ABG sampling 5 minutes before ABG attempts (group A) or lidocaine gel to the site of ABG sampling 5 minutes before ABG attempts (group B).

Patient selection

Two groups with 21 patients each were selected based on a projected difference of 20% in the success of ABG between the 2 groups and a power (1 – ?) of 0.8 at the .05 level of significance (?). Patients who needed ABG and were alert and cooperative were eligible for the study. We undertook a prospective study in 42 volunteers requiring ABG as part of their management in the ED. Patients were excluded if they met any of the following criteria: (a) history of analgesic medication used within 6 hours of enrollment (except for nonsteroidal anti-inflammatory drugs and acetaminophen),

(b) any sign of decreased consciousness, (c) history of skin hypersensitivity or lidocaine allergy, (d) inability to report a pain score, (e) history of a known neurological problem that changes pain perception, (f) history of methemoglobinemia, or (g) language barrier.

Materials

Standardized 29-gauge needles were used for ABG sampling in both groups. The needle-free injector device consists of the following parts: (a) stainless steel jet injector,

(b) sterile ampul, and (c) sterile adapter for transferring the medication from the vial into the ampul for injection.

Measures

Pain after the ABG sampling was recorded according to the Visual analog scale scoring method, where scores range from 0 to 10. The 0 end of the scale was represented visually as no pain, and the 10 end of the scale was visually represented as worst imaginable pain. The patient’s mark on the line represented the pain intensity experienced during the procedure, and the VAS was scored by measuring the distance from the “no pain” end to the patient’s mark. The resident skilled in performing ABG

sampling reported the number of attempts at ABG sampling and ease of the procedure using a dichotomous scale (easy or difficult).

Table 2 Comparing pain and number of tries in the group using jet injector and the group using conventional method
Variable	Using jet injector (n = 21)	Conventional method (n = 21)	P
VAS score, mean +- SD	1.29 +- 0.90	4.19 +- 1.43	.001
No. of tries	1.29 +- 0.46	2.10 +- 1.26	.011

Method

Altogether, 42 patients were enrolled and screened for participation and evenly distributed to 2 groups: group A, patients who received 0.2 mL of lidocaine 2% via jet injector, and group B (control group), patients who received 1 mL of lidocaine gel 2% applied topically. The procedure is designed for taking the ABG sample in less than 6 minutes. The jet injector cartridge is loaded with 0.2 mL of lidocaine 2%. Then, it is connected to the injector. To ensure that this injection would anesthetize the skin, the lidocaine was shot 2 cm above the skin. The ABG procedure was performed 5 minutes after administering lidocaine in both groups. Arterial blood gas samplings were performed by ED residents all in their third year of residency. The residents were trained in and had previous experience with ABG sampling. They recorded the patient’s pain score after the ABG sampling. The researcher chose the patient’s group randomly and applied the jet injector in group A or 1 mL of lidocaine gel 2% in group B without the resident’s or patient’s knowledge. Then, the residents were asked to take ABG samples from those patients. Therefore, neither residents nor patients knew which kind of intervention had been performed.

Statistical analysis

More than 1 unit of difference in the VAS score was considered clinically relevant and statistically significant. The 2 groups were compared on continuous variables with the Mann-Whitney U test or an independent-samples t test. For categorical variables, Fisher exact tests were used. P b

.05 was considered statistically significant.

Results

There was no significant difference between the mean ages in groups A and B (58.62 +- 19.15 vs 50.90 +- 20.66 years; P = .217, Mann-Whitney U test). There was also no significant difference between the sex ratios in groups A and

Table 1 Characteristics of the study population in the group using jet injector and the group using conventional method

Variable Using jet

injector (n = 21)

52 (19-85)

6 (35)

Conventional method

(n = 21)

60 (21-89)

11 (65)

P

Age (y), median (range) Female sex, n (%)

.217

.208

B (15 male and 6 female vs 10 male and 11 female; P = .208, Fisher exact tests; Table 1). Visual Analog Scale score during ABG sampling was considerably lower in group A compared with group B (1.29 +- 0.90 vs 4.19 +- 1.43; P b

.001, Mann-Whitney U test). The number of attempts required for ABG sampling was significantly lower in group A compared with group B (1.29 +- 0.46 vs 2.1 +- 0.12;

P = .009; Table 2).

All the residents reported that ABG sampling was easy using the lidocaine jet injection procedure (group A; P b .05).

Discussion

This is the first study conducted analyzing the use of lidocaine needleless injection before ABG sampling; how- ever, studies on other procedures such as intravenous cannulation using jet injection have reported the useful role of the lidocaine jet injector for controlling pain [6,8,9,15,16]. Our study showed that using the lidocaine jet injector device before ABG sampling reduces pain remarkably. It also showed that use of the jet injector significantly reduced the average number of unsuccessful attempts at sampling. The pain of ABG sampling is difficult for the patient, especially when the procedure must be performed mul- tiple times due to indication or sampling failure. Further- more, the patient’s pain makes the practitioner uneasy while performing the procedure. Therefore, the more the patient’s pain is relieved, the more likely successful ABG

sampling would seem.

The jet injector device has many benefits, including no needle involvement, rapid onset of action, affordability, and absence of vasoconstriction. In addition, this device has no complication for the patients such as hematoma formation. All of these advantages may explain why there is an increasing tendency for practitioners to use jet injection technology [7,9,17-19]. In our study, after using the jet injection technique and informing the residents about the procedure that was done before ABG, the residents entirely approved simplicity during ABG. Moreover, they requested to use it in the routine ABG sampling in our crowded ED.

Lightowler and Elliot [20] recommended using a subcutaneous bolus of lidocaine before Arterial puncture.

They observed that infiltration with lidocaine was not more painful than the placebo group in their study. Their finding is in agreement with some other studies [21]. Sado and Deakin [22] in their study showed that 40% of anesthetists and 98% of ward doctors do not use local anesthesia before ABG sampling.

One of the anesthetic techniques that can be used before unpleasant procedures is using lidocaine creams such as tetracaine, EMLA, or LMX [23-26]. However, it seems that creams are not useful in reducing pain during ABG procedures. Aaron et al [27] reported that tetracaine gel is not valuable for decreasing patient pain during the ABG procedure. Tran et al [28] showed that topical use of 4% amethocaine gel did not reduce the pain of ABG sampling. Giner et al [29] concluded that using EMLA anesthetic cream is not helpful against pain caused by ABG sampling. These creams are also expensive, and they can take 30 minutes or more to take effect, which is a major limitation in a busy ED surgical system needing swift diagnosis and treatment [16,30]. Despite the fact that vasodilation of the lidocaine would increase the amount of bleeding [31], no obvious bleeding was seen, as the needle for ABG sampling is so thin (29-gauge needle in our study).

The jet injector is a cheap device that is approved by the Food and Drug Administration. It will inject a drug to a depth of 5 to 8 mm of epidermis in 0.2 seconds [16]. Thicker subcutaneous tissue in pediatric patients allows the local anesthetic to penetrate deeper [8]. Therefore, it seems that the same, if not better, results in analgesia would be seen in pediatrics; however, more double-blinded studies on the use of the jet injector before ABG sampling in the hand and the femoral artery in children and adults are necessary.

Conclusion

This is the first study, as far as we know, demonstrating that the needle-free injection of lidocaine is an effective, useful, and noninvasive method for making ABG sampling easier. This study demonstrates that jet injection of 2% lidocaine provides beneficial and rapid anesthesia, which results in less pain and fewer procedure failures. Lidocaine jet injection is recommended for use before ABG sampling to decrease patient pain and the number of sampling attempts and to improve the patient’s quality of service in the ED.

References

1. Gaakeer MI, Veugelers R, Houser CM, Berben SA, Bierens JJ. Acute pain at the emergency department: better treatment required. Ned Tijdschr Geneeskd 2011;155(2):A2241.
2. Martin JS, Spirig R. pain prevalence and patient preferences concerning pain management in the emergency department. Pflege 2006;19(6):326-34.
3. Berben SA, Meijs TH, van Dongen RT, van Vugt AB, Vloet LC, Mintjes-de Groot JJ, et al. Pain prevalence and pain relief in trauma patients in the accident & emergency department. Injury 2008;39(5): 578-85.
4. Tanabe P, Buschmann M. A prospective study of ED pain management practices and the patient’s perspective. J Emerg Nurs 1999;25(3):171-7.
5. Downey LV, Zun LS. Pain management in the emergency department and its relationship to patient satisfaction. J Emerg Trauma Shock 2010;3(4):326-30.
6. Cooper JA, Bromley LM, Baranowski AP, Barker SG. Evaluation of a needle-free injection system for local anaesthesia prior to venous cannulation. Anaesthesia 2000;55(3):247-50.
7. Bennett J, Nichols F, Rosenblum M, Condry J. Subcutaneous administration of midazolam: a comparison of the Bioject jet injector with the conventional syringe and needle. J Oral Maxillofac Surg 1998;56(11):1249-54.
8. Lysakowski C, Dumont L, Tramer MR, Tassonyi E. A needle-free jet-injection system with lidocaine for peripheral intravenous cannula insertion: a randomized controlled trial with cost-effectiveness analysis. Anesth Analg 2003;96(1):215-9 table of contents.
9. Koenig HM, Paisansathan C, Albrecht II RF, Zsigmond EK. Jet injection of local anesthetic decreases pain of arterial cannulation in awake neurosurgical patients. J Neurosurg Anesthesiol 2004;16(2): 156-9.
10. Florentine BD, Frankel K, Raza A, Cobb CJ, Greaves T, Carriere C, et al. Local anesthesia for fine-needle aspiration biopsy of palpable breast masses: the effectiveness of a jet injection system. Diagn Cytopathol 1997;17(6):472-6.
11. Ellis GL, Owens A. The efficacy and acceptability of using a jet injector in performing digital blocks. Am J Emerg Med 1993;11(6): 648-50.
12. Gursoy A, Ertugrul DT, Sahin M, Tutuncu NB, Demirer AN, Demirag NG. Needle-free delivery of lidocaine for reducing the pain associated with the fine-needle aspiration biopsy of thyroid nodules: time-saving and efficacioUS procedure. Thyroid 2007; 17(4):317-21.
13. Peter DJ, Scott JP, Watkins HC, Frasure HE. Subcutaneous lidocaine delivered by jet-injector for pain control before IV catheterization in the ED: the patients’ perception and preference. Am J Emerg Med 2002;20(6):562-6.
14. Zsigmond EK, Darby P, Koenig HM, Goll EF. Painless intravenous catheterization by intradermal jet injection of lidocaine: a randomized trial. J Clin Anesth 1999;11(2):87-94.
15. Spanos S, Booth R, Koenig H, Sikes K, GRACEly E, Kim IK. Jet injection of 1% buffered lidocaine versus topical ELA-Max for anesthesia before peripheral intravenous catheterization in children: a randomized controlled trial. Pediatr Emerg Care 2008;24(8): 511-5.
16. Jimenez N, Bradford H, Seidel KD, Sousa M, Lynn AM. A comparison of a needle-free injection system for local anesthesia versus EMLA for intravenous catheter insertion in the pediatric patient. Anesth Analg 2006;102(2):411-4.
17. Greenberg RS, Maxwell LG, Zahurak M, Yaster M. Preanesthetic medication of children with midazolam using the Biojector jet injector. Anesthesiology 1995;83(2):264-9.
18. Zsigmond EK, Darby P, Koenig HM, Goll EV. A new route, jet injection of lidocaine for skin wheal for painless intravenous catheterization. Int J Clin Pharmacol Ther 1999;37(2):90-9.
19. Fine B, Castillo R, McDonald T, Paisansathan C, Zsigmond E, Hoffman WE. Jet injector compared with oral midazolam for preoperative sedation in children. Paediatr Anaesth 2004;14(9): 739-43.
20. Lightowler JV, Elliott MW. Local anaesthetic infiltration prior to arterial puncture for blood gas analysis: a survey of current practice and a randomised double blind placebo controlled trial. J R Coll Physicians Lond 1997;31(6):645-6.
21. Giner J, Casan P, Belda J, Gonzalez M, Miralda RM, Sanchis J. Pain during arterial puncture. Chest 1996;110(6):1443-5.
22. Sado DM, Deakin CD. Local anaesthesia for venous cannulation and arterial blood gas sampling: are doctors using it? J R Soc Med 2005; 98(4):158-60.
23. Valdovinos NC, Reddin C, Bernard C, Shafer B, Tanabe P. The use of Topical anesthesia during intravenous catheter insertion in adults: a comparison of pain scores using LMX-4 versus placebo. J Emerg Nurs 2009;35(4):299-304.
24. Guardiano RA, Norwood CW. Direct comparison of EMLA versus lidocaine for pain control in Nd:YAG 1,064 nm laser hair removal. Dermatol Surg 2005;31(4):396-8.
25. Smith DP, Gjellum M. The efficacy of LMX versus EMLA for pain relief in boys undergoing office meatotomy. J Urol 2004;172(4 Pt 2): 1760-1.
26. Lullmann B, Leonhardt J, Metzelder M, Hoy L, Gerr H, Linderkamp C, et al. pain reduction in children during port-a-cath catheter puncture

using local anaesthesia with EMLA. Eur J Pediatr 2010;169(12): 1465-9.

1. Aaron SD, Vandemheen KL, Naftel SA, Lewis MJ, Rodger MA. Topical tetracaine prior to arterial puncture: a randomized, placebo- controlled clinical trial. Respir Med 2003;97(11):1195-9.
2. Tran NQ, Pretto JJ, Worsnop CJ. A randomized controlled trial of the effectiveness of topical amethocaine in reducing pain during arterial puncture. Chest 2002;122(4):1357-60.
3. Giner J, Casan P, Belda J, Litvan H, Sanchis J. Use of the anesthetic cream EMLA in arterial punction. Rev Esp Anestesiol Reanim 2000; 47(2):63-6.
4. Cordoni A, Cordoni LE. Eutectic mixture of local anesthetics reduces pain during intravenous catheter insertion in the pediatric patient. Clin J Pain 2001;17(2):115-8.
5. Newton DJ, McLeod GA, Khan F, Belch JJ. Mechanisms influencing the vasoactive effects of lidocaine in human skin. Anaesthesia 2007; 62(2):146-50.