Minimizing the Pain of Local Anesthesia Injection

Abstract

There are now excellent techniques for minimizing anesthetic injection pain, with supporting evidence varying from anecdotal to systematic reviews. Medical students and residents can easily learn techniques that reliably limit the pain of local anesthetic injection to the minimal discomfort of only the first fine needlestick. By combining many of these conclusions and techniques offered in the literature, tumescent local anesthetic can be administered to a substantial area such as a hand and forearm for tendon transfers or a face for rhytidectomy, with the patient feeling just the initial poke.

Prospective Study of a Single Treatment Strategy for Local Tumescent Anesthesia in Muller Phlebectomy

“…11 Lidocaine 1% with epinephrine has a pH of 4.2, which is 1,000 times more acidic than the physiological pH of subcutaneous tissue. 12 A Cochrane review states that increasing pH of lidocaine decreases pain associated with infiltration. 9 Moreover, it has been demonstrated that sodium bicarbonate solution may be used to alkalinize LTA, keeping in mind that alkalinization of local anesthetic may cause precipitation and loss of potency.…”

“…Proper volume ratio of sodium bicarbonate 8.4% to lidocaine 1% with 1:100.000 epinephrine for buffering and effectively raising the pH to 7.4, is approximately 1 mL: 10 mL. 12 Till date, no consensus on concentration of sodium bicarbonate has been obtained. Peterfreund et al 15 investigated 2 commercially available sodium bicarbonate precipitations of 4% and 8.4%.…”

“…Furthermore, injecting technique is also important in pain experience: use of topical anesthetic cr emes, using smaller needles, using fresh and sharp needles for every infiltration, inserting the needle perpendicular to the skin, inserting needle subdermal instead of intradermal, injecting slowly, and injecting a small subdermal bleb and then pause. 12 Drawback of our study is the unknown factor of time between injection and start of intervention. As shown previously, time can influence pain interpretation of patients treated with LTA.…”

Nail Surgery

“…Buffering to physiologic pH can be performed simply by adding 1 to 1.8 ml of 8.4% sodium bicarbonate to 10 ml of lidocaine premixed with epinephrine, producing a mixture with a near physiologic pH. [11][12][13] This practice has been supported by a recent Cochrane review and meta-analysis. 14,15 Not only is the neutral pH solution less painful during injection, but it also facilitates more efficient anesthesia.…”

Use of WALLANT technique in hand surgery, safe and advantageous. Personal experience

“…Taking into account these recommendations, in our study we used volumes of anesthetic solution of 8.5 mL to 15 mL per digital ray affected by DD, 8 mL to 20 mL for CTS, and 3 mL to 6 mL for trigger finger. Lalonde and other authors have studied the technique of injecting the anesthetic solution to produce minimal pain proposing that lidocaine and epinephrine 10:1 to be buffered with 8.4% bicarbonate; the anesthetic solution to be warmed at body temperature, the use of thin needles, insertion of the needle perpendicular to the skin with the injection of the first 0.5 mL subdermally until the patient no longer feels pain, then the anesthetic to be gradually injected, and the area of injection to be distracted with touch, pinch, or pressure (11,12). The anesthetic solution used in our study was not buffered with 8.4% bicarbonate, but we followed the recommendations regarding how to inject the anesthetic to cause less pain to the patient.…”