Simon Woods

Laparoscopic gastric banding: Safe and modestly successful

Background:  Obesity is an increasing problem in Australia. It is defined as a body mass index (BMI) >30 kg/m2. It is associated with a number of significant medical conditions, as well as psychological morbidity related to poor body image and the social stigma of obesity. Conservative management is rarely successful in patients with morbid obesity and bariatric surgery is an alternative more likely to produce sustained results.

LOCAL ANAESTHETIC REDUCES THE PAIN OF DRAIN TUBE REMOVAL

The insertion of a drain tube into the peritoneal cavity after abdominal surgery is common practice. This drain tube is usually removed on the ward by nursing staff. Removal of the drain tube can cause considerable pain. Local anaesthetic (LA) is sometimes injected into the tissues surrounding the drain tube in an attempt to reduce the pain. There is no evidence in the published work regarding the effectiveness of LA infiltration for abdominal drain tube removal. We aimed to determine whether the injection of LA into the deep tissues adjacent to the drain tube is effective in reducing the pain associated with its removal. Furthermore, we aimed to determine whether the pain associated with the injection of the LA offsets any reduction in pain when the drain tube is removed. Consecutive patients who had i.p. drain tubes inserted during abdominal surgery and who had completed an informed consent process were eligible to participate in the trial. Patients were excluded if they were unable to complete the informed consent process or if they had experienced an allergic reaction to LA in the past. We conducted a double-blinded, randomized, placebocontrolled trial, comparing an injection of 10mL of 1% lignocaine with the injection of 10mL of normal saline. Injection was into the deep tissues surrounding the drain tube immediately before the removal of their drain tube. The researcher, in a sterile fashion, filled two 5-mL syringes with either 1% lignocaine or normal saline and then attached a 23-G sterile needle to each syringe. The researcher cleaned the area around the drain tube using a 70% isopropyl alcohol sterile swab. The fluid was injected into the deep tissues adjacent to the drain tube, in each of the four quadrants approximately 1 cm from the edge of the drain. The researcher then assessed the pain experienced after each of the two injections by asking the patient to place a line on a linear analogue pain score form. The first pain score forms were then taken away. Approximately 5min later, the drain tube was removed in the standard manner by the nursing staff. Then, the nurse asked the patient to complete a second pain score form, indicating the level of pain experienced during the removal of the drain tube. The primary end-point was a significant reduction in visual analogue pain scores associated with the removal of abdominal drain tubes. Baseline variables recorded included the sex and age of the patient and the type of drain tube. Visual analogue pain scores were measured for the injections and on removal of the drain tube. Pain scores were determined using a 10-cm visual analogue pain score with indicators at 0 ‘no pain’ and 10 ‘worst pain possible’. A total of 125 patients were enrolled in the trial from October 2002 to May 2003. A computer-generated random numbers list was used to determine the substance received by each patient. As consecutive patients were enrolled into the trial they were assigned the next number on this list, which would determine if they were to receive LA or normal saline. The researcher, a medical practitioner, completed the informed consent process, enrolled and assigned the patients a trial number. The researcher then determined which intervention the patient would receive according to the randomization list. The researcher then conducted the intervention (either active or placebo) and measured the pain associated with the injections. Therefore, the researcher was not blinded to the intervention. The patient, however, was blinded to the intervention. The nurse removing the drain tube, who assessed the level of pain the patient experienced during its removal was blinded to the intervention. All analyses were carried out using a commercially available statistical software package (SAS version 8.2; SAS Institute, Cary, NC, USA). A univariate analysis of the data was carried out using a v2 test. A two-sided P-value of 0.05 or less was considered to be statistically significant. Univariate analysis of the data showed significantly less pain on removal of the drain tube in patients who received LA compared with those who received normal saline (P = 0.034) as shown in Table 1. The use of LAwas beneficial in all types of drain tubes. The pain associated with the injections was less than the pain associated with the removal of the drain tube. Injections were associated with minor pain and there was no significant difference between normal saline and LA. We have shown that the injection of LA into the deep tissues surrounding a drain tube significantly reduces the pain associated with its removal, compared to placebo. In particular, we have shown a reduction in pain scores ranging from 16.9 to 57.6% for the removal of various types of drain tubes. A Greek study comparing the use of LA versus placebo in the removal of suction drains in lower limb orthopaedic surgery showed significantly reduced pain on post-removal in the study group.1 Similar trials have also been carried out for chest drain removal in postcardiac surgical patients, which reported reduced pain with the use of local anaesthetic.2 A search of published work did not show any trials that used LA with abdominal drain tube removals. However, there is no doubt that some patients find the removal of a drain tube a distressing experience. Anecdotally