N Engl J Med 1997 Apr 24;336(17):1197-1201
Department of Paediatrics, Hospital for Sick Children, Toronto, ON, Canada.
BACKGROUND: Neonatal circumcision is a painful surgical procedure often performed without analgesia. We assessed the efficacy and safety of 5 percent lidocaine-prilocaine cream (Emla) in neonates undergoing circumcision. METHODS: We carried out a double-blind, randomized, controlled trial in 68 full-term male neonates: 38 were assigned to receive lidocaine-prilocaine cream, and 30 to receive placebo. One gram of lidocaine-prilocaine or placebo cream was applied to the penis under an occlusive dressing for 60 to 80 minutes before circumcision. Behavioral (facial activity and time spent crying) and physiologic (heart rate and blood pressure) responses were recorded during the procedure. Blood samples were obtained at various times after drug application for measurements of methemoglobin and plasma lidocaine, prilocaine, and o-toluidine (a metabolite of prilocaine). RESULTS: A total of 68 and 59 neonates were included in the safety and efficacy analyses, respectively. Demographic characteristics such as gestational age and birth weight did not differ between the lidocaine-prilocaine and placebo groups. During circumcision, the neonates in the lidocaine-prilocaine group had less facial activity (P= 0.01), spent less time crying (P<0.001), and had smaller increases in heart rate (P=0.007) than the neonates in the placebo group. Facial-activity scores were 12 to 49 percent lower during various steps of the procedure in the lidocaine-prilocaine group. As compared with neonates in the placebo group, infants in the lidocaine-prilocaine group cried less than half as much and had heart-rate increases of 10 beats per minute less. Blood methemoglobin concentrations (expressed as a percentage of the hemoglobin concentration) were similar (1.3 percent) in both groups. Lidocaine and prilocaine were detected in plasma in 23 (61 percent) and 21 (55 percent) of the infants treated with lidocaine-prilocaine cream, respectively. CONCLUSIONS: Lidocaine-prilocaine cream is efficacious and safe for the prevention of pain from circumcision in neonates.
J Am Board Fam Pract 1997 Jan;10(1):13-19
University of Nevada School of Medicine, Reno, USA.
BACKGROUND AND OBJECTIVES: Circumcision is the most commonly performed surgical procedure in the United States, and it is painful. Several investigators have independently documented the reliability and safety of local anesthesia in eliminating the pain associated with circumcision. Investigations have not, however, been conducted to determine which technique is most effective in reducing the pain of the procedure. This study compares the techniques of local anesthesia for circumcision to determine which technique most safely and reliably reduces pain. METHODS: Fifty-six infants being circumcised were randomly assigned to one of three groups according to anesthesia technique: (1) distal branch block, (2) root block, and (3) subpubic block. Change in heart rate and oxygen saturation, as well as cry response, were recorded. Heart rate and oxygen saturation differences were analyzed utilizing Student's t test, whereas cry response was analyzed using the chi-square test. RESULTS: We discontinued using the distal branch block technique during the study because we were concerned about possible untoward outcomes. As a result, only data from the circumcisions of the 42 infants who were assigned to the root block and subpubic block groups were analyzed. The dorsal penile nerve root block more reliably reduced the pain of circumcision than did the subpubic technique (P = 0.05). There were no serious complications with any of the techniques in this study. CONCLUSIONS: Compared with distal branch block and subpubic block techniques, nerve block at the penile root most reliably and safely eliminated the pain of circumcision.
Anaesth Intensive Care 1996 Jun;24(3):365-367
University of Hong Kong.
A randomized, prospective, blind trial was conducted comparing caudal epidural blockade (caudal block) with subcutaneous ring block of the penis (penile ring block) in fifty healthy boys between two and twelve years of age undergoing elective circumcision. Subjects receiving caudal block had a longer duration of analgesia (P = 0.003), and took longer to first micturition (P = 0.04) but there was no difference in time taken to awaken from anaesthesia or spontaneously walk unaided. There was an 8% failure rate with the penile ring block but no local or systemic complications related to either block and a very low incidence of vomiting. It is concluded that both techniques are effective. Caudal block is more reliable and produces a longer duration of analgesia but penile ring block is inherently safer and has a lower incidence of adverse effects.
Can J Anaesth 1994 Dec;41(12):1181-1184
Department of Anesthesiology, Kaplan Hospital, Rehovot, Israel.
Penile block (PB) in adults is not a well-recognized technique. The aim of this study was to compare, in a randomized prospective manner, five different techniques of PB in 250 adults undergoing circumcision with regard to anaesthetic quality, complications and postoperative analgesia. Patients were divided into five groups (50 per group) according to the technique used: Group A--"10, 30-13, 30" approach; Group B--the subpubic approach; Group C--subcutaneous ring block; Group D--a combination of frenulum infiltration and the "10, 30-13, 30" approach; Group E--a combination of frenulum infiltration and the subpubic approach. The number of failed blocks in Groups A and B (41 and 43 respectively) was greater than in Groups C, D and E (2, 3 and 5 respectively) (P < 0.001). The five groups did not differ with regard to adverse effects or time until the onset of postoperative pain when the blocks were successful. It is concluded that good surgical anaesthesia, a low rate of adverse effects and prolonged postoperative analgesia can be achieved by the use of either subcutaneous ring block or a combination of dorsal nerve block (using the "10, 30-13, 30" or the subpubic approach) and infiltration of the frenulum. These approaches to the PB are effective anaesthetic techniques for circumcision in adults.
Agressologie 1990 Jan;31(1):39-42
[Article in French]
Departement d'anesthesie-reanimation B. Centre hospitalier general Andre Boulloche-Montbeliard.
Circumcision in children is followed by severe pain. This study analysed retrospectively anesthetic techniques of 110 children from 17 months to 14 years old who had undergone ambulatory of 24 h stay circumcision. There were two groups of patients: one being operated on under locoregional techniques combined with general anesthesia (53.6%), the other one under general anesthesia alone (46.4%). Post operative analgesia was provided by the regional anesthesia (with or without additional analgesics via rectal route) for the former group whereas analgesic drugs were administered only rectally for the latter one. In this second group, pain relief assessment was insufficiently recorded and was considered poor. In the first group, dorsal nerves block of the penis (DNBP) was performed on 47 children (79.8% of the locoregional techniques), caudal block on 10 patients and ring block on 2 patients. Regional techniques offered a satisfactory, safe and reliably effective post circumcision analgesia. DNBP should be used systematically in order to shorten duration of day circumcision stay.