2.
Anaphylactic reactions to local anesthetics.
Ring, J, Franz, R, Brockow, K
Chemical immunology and allergy. 2010;:190-200
Abstract
Local anesthetics (LA) are common elicitors of adverse reactions and the clinical symptoms often correspond to anaphylaxis with tachycardia, hypotension and subjective feelings of weakness, heat or vertigo. The pathomechanism of immediate hypersensitivity reactions to LA is largely unknown -they are commonly regarded as 'pseudo-allergic' or 'non-immune type' anaphylaxis. Immunologically mediated reactions have rarely been observed with positive skin prick tests. Other ingredients in LA preparations have to be considered as elicitors, e.g. preservatives like benzoates or sulfites or latex contaminants in injection bottles. Practical management of patients with a history of LA reaction includes a careful allergy history, skin-prick and intradermal tests. Undiluted LA solutions may elicit false-positive intradermal test reactions. If prick and intradermal tests are negative, the procedure of subcutaneous provocation testing is applied in a placebo-controlled manner. When patients are constantly reacting to placebo, a regimen of 'reverse placebo provocation' with injection of a LA (verum) is applied while the patient is informed about receiving placebo in order to 'rule out psychosomatic involvement'. With this regimen it is possible to eliminate anxiousness and fear, and the patient has proof that he has tolerated the respective LA substance.
3.
The effect of perioperative intravenous lidocaine on postoperative pain and immune function.
Yardeni, IZ, Beilin, B, Mayburd, E, Levinson, Y, Bessler, H
Anesthesia and analgesia. 2009;(5):1464-9
Abstract
BACKGROUND Surgery-associated tissue injury leads to nociception and inflammatory reaction, accompanied by increased production of proinflammatory cytokines. These cytokines can induce peripheral and central sensitization, leading to pain augmentation. Recently, a frequently used local anesthetic, lidocaine, was introduced as a part of a perioperative pain management technique. In addition to its analgesic effects, lidocaine has an antiinflammatory property, decreasing the upregulation of proinflammatory cytokines. We focused on the effects of preincisional and intraoperative IV lidocaine on pain intensity and immune reactivity in the postoperative period. METHODS Sixty-five female patients (ASA physical status I-II) scheduled for transabdominal hysterectomy were recruited to this randomized, placebo-controlled study. Thirty-two patients in the treatment group received IV lidocaine starting 20 min before surgery, whereas the control group (33 patients) received a matched saline infusion. Both groups received patient-controlled epidural analgesia during the postoperative period. Blood samples were collected before, 24, 48, and 72 h after surgery to measure ex vivo cytokine production of interleukin (IL)-1 receptor antagonist (IL-1ra) and IL-6, as well lymphocyte mitogenic response to phytohemagglutinin-M. A 10-cm visual analog scale was used to assess pain intensity at rest and after coughing. RESULTS Patients in the lidocaine + patient-controlled epidural analgesia group experienced less severe postoperative pain in the first 4 and 8 h after surgery (visual analog scale 4/3.7 at rest and 5.3/5 during coughing versus 4.5/4.2 and 6.1/5.3, respectively, in the placebo group). There was significantly less ex vivo production of IL-1ra and IL-6, whereas the lymphocyte proliferation response to phytohemagglutinin-M was better maintained than in the control group. CONCLUSION The present findings indicate that preoperative and intraoperative IV lidocaine improves immediate postoperative pain management and reduces surgery-induced immune alterations.