Reducing bleeding and pain during epidural catheter insertion

AORN Journal,  Sept, 2007  by George Allen

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International Journal of Obstetric Anesthesia

April 2007

Epidural catheter insertion, which is commonly used for administering epidural analgesia during labor, is associated with superficial bleeding. In a number of surgical settings, epinephrine-containing local anesthetic solution has been shown to reduce perioperative bleeding from surgical wound sites. No studies, however, have determined whether adding epinephrine to the lidocaine used for local infiltration reduces the amount of superficial bleeding at the site of the epidural needle insertion. Additionally, some investigators have reported more painful skin and subcutaneous infiltration with epinephrine-containing lidocaine and that the addition of sodium bicarbonate to the lidocaine attenuates the pain on skin infiltration.

The primary purpose of this randomized, double-blinded study was to determine whether infiltrating the skin with epinephrine-containing lidocaine rather than plain lidocaine reduces superficial bleeding after placement of an epidural catheter. Secondary objectives were to determine whether an epinephrine-containing solution results in more pain during local infiltration and whether this pain is attenuated by the addition of sodium bicarbonate.

At a labor and deliver suite in Stanford, California, 80 healthy women aged 18 to 45 years with an American Society of Anesthesiologists Physical Status Classification of 1 or 2 who requested epidural analgesia during labor were randomly assigned to have local anesthetic infiltration using one of four methods. Twenty patients were assigned to each group. Participants in group I received 1.5% plain lidocaine, those in group II received plain lidocaine with sodium bicarbonate, participants in group III received lidocaine with epinephrine, and those in group IV received lidocaine with epinephrine and sodium bicarbonate. Exclusion criteria were any conditions that may lead to difficult catheter insertions, including

* maternal weight greater than 100 kg,

* scoliosis,

* previous back surgery,

* a history of prior difficult epidural placement, and

* any significant medical or obstetric condition.

Clinical endpoints included the amount of superficial bleeding at the catheter site, pain during local anesthetic infiltration, and epidural catheter movement during labor. The amount of superficial skin bleeding was rated by the study investigators using a 4-point Likert-type categorical rating scale with possible answers of none, mild, moderate, and heavy superficial bleeding compared to the investigators' previous experience with superficial bleeding during epidural placement. Additionally, a visual analogue investigators' satisfaction score (ie, zero to 100, in which zero equals extremely dissatisfied and 100 equals extremely satisfied) with the amount of superficial bleeding was obtained, and the number of times the site was dabbed with a gauze sponge before the superficial bleeding was stopped were counted.

Pain was evaluated by the patient using a numerical verbal pain score (ie, zero to 10, in which zero equals no pain and 10 equals worst pain imaginable) and a 4-point Likert-type categorical rating scale with possible answers of none, mild, moderate, and severe pain. Maternal blood pressure and heart rate were recorded before and up to five minutes after subcutaneous infiltration of the local anesthetic. The degree of movement of the epidural catheter was measured at the time of catheter removal after delivery. Common statistical techniques, including the Student t test, Kruskal-Wallis test, and analysis of variance, were used to analyze the differences between the groups.

FINDINGS. All the epinephrine-containing local anesthetic solutions were well tolerated without any side effects. There was significantly less superficial bleeding after epidural catheter insertion with epinephrine-containing lidocaine versus plain lidocaine (P > .01). Additionally, there was a trend toward lower pain scores when the local anesthetic contained bicarbonate. Pain scores among patients in the groups that received bicarbonate were 2.6 [+ or -] 1.8 compared to 3.6 [+ or -] 2.2 in the groups in which patients did not receive bicarbonate (P = .04). None of the epidural catheters became dislodged during the study, and there was no difference among the groups in the movement of the epidural catheters relative to the skin at the time of catheter removal.

CLINICAL IMPLICATIONS. The results of this study revealed that there is less superficial bleeding after epidural catheter insertion with an epinephrine-containing lidocaine solution and that the epinephrine-containing solution did not result in more painful skin infiltration. Perioperative nurses should understand that the results of this study suggest that lidocaine 1.5% with epinephrine 1:200,000 and 8.4% sodium bicarbonate is an effective local anesthetic mixture for skin infiltration before the placement of an epidural catheter for labor. Consequently, nurses should be prepared to have lidocaine with epinephrine and sodium bicarbonate readily available when an epidural catheter for labor is planned.