Abstract ID: A18
Abstract Title: THE EFFECT OF REGIONAL vs. GENERAL ANESTHESIA ON PARESTHESIAE ONE YEAR AFTER AMBULATORY HAND SURGERY
Poster Type: Either
ABSTRACT BODY
Introduction: Regional anesthesia (RA) is often implicated in postoperative neuropathy with insufficient evidence.[1,2] To date, there are no prospective randomized investigations of long-term postoperative neuropathy in patients receiving RA compared to general anesthesia (GA) for upper extremity surgery. The purpose of this study is to determine whether RA or GA affects the incidence of postoperative paresthesiae up to 12 months following ambulatory hand surgery.
Materials and Methods: After IRB approval and informed consent, 100 patients ASA I-III undergoing ambulatory hand surgery were randomly allocated to RA (n=50) or GA (n=50).[3] RA comprised of a transarterial axillary brachial plexus block (AXB) with lidocaine 1.5% 10 mg kg-1 and epinephrine 1:200 000 injected incrementally via a 1-inch 23-gauge non-insulated long-beveled needle. A standard balanced short-acting protocol was administered for GA. A tourniquet inflated to 100 mmHg above the systolic blood pressure was applied to the operative arm in all patients, after which the arm was padded to rest on an operating table. Patients reported the incidence of paresthesiae (“numbness” or “tingling”) in the operative extremity at 1 day, 1 week, 2 weeks, 3 months, and 12 months postoperatively. Intention-to-treat analysis was undertaken by t-test, Mann-Whitney U, or χ2 with the Bonferroni correction. Significance was considered at p<0.05. Data are presented as mean ± SD.
Results: Demographics (except weight), types of hand surgery, surgeon, duration of surgery (RA 54.4 ± 23.1, GA 62.0 ± 24.4 min; p=0.111), tourniquet inflation pressure (RA 245 ± 35.3, GA 245 ± 35.3 mmHg; p=1.00), and duration of tourniquet inflation (RA 44.6 ± 20.3, GA 51.6 ± 22.4 min; p=0.103) were similar between groups. Five patients randomized to RA required conversion to GA. During AXB administration, the median number of needle-skin punctures (i.e. attempts) was 1 (range: 1-7), and needle-skin penetration lasted 7.7 ± 5.8 min per patient, while incidental transient paresthesiae occurred in 33 patients. No patients complained of intense pain upon injection of local anesthetic suggestive of intraneural injection during AXB. Postoperatively, the incidence of reported paresthesiae in the operative extremity was similar between groups at each measured time interval (figure 1), and notably identical in both groups at 3 months (RA 11, GA 11 patients; p=0.358) and 12 months (RA 6, GA 6 patients; p=0.212) after surgery. The incidence of paresthesiae in RA patients at 12 months postoperatively was not associated with the amount of needle-skin punctures (p=0.804), duration of needle-skin penetration (p=0.274), or occurrence of incidental transient paresthesiae (p=0.339) upon AXB administration.
Discussion: Paresthesiae in the operative extremity occur frequently after ambulatory hand surgery. However, our results suggest that anesthetic type, either RA or GA, does not affect the incidence of paresthesiae up to 12 months following ambulatory hand surgery.
References: [1] Anesthesiology 1999; 90: 1062-9. [2] Anesthesiology 2004; 101: 143-52. [3] Anesthesiology 2004; 101: 461-7.
ATTACHED FILES
A18_Figure.ASRA2005.doc
Reg Anesth Pain Med 2004; 29(2):A18