***TASK***
the task is to simplify the input abstract of a biomedical literature

***INPUT***
the input is the abstract of a biomedical literature

***OUTPUT***
the output is the simplified abstract for the input abstract of a biomedical literature

***DOCUMENTATION***

***EXAMPLES***

Input: We included four RCTs with 167 participants. Risk of bias of the included studies was high, as none of them reported method of randomization, allocation concealment or blinding. Only one trial mentioned our primary outcome of duration of anaesthesia. The mean difference in duration of anaesthesia with use of adrenaline with lidocaine was 3.20 hours (95% confidence interval (CI) 2.48 to 3.92 hours; one RCT, 20 participants; low-quality evidence). No trial reported adverse events such as ischaemia distal to the injection site, and no trial reported cost analysis. One trial mentioned the secondary outcome of duration of postoperative pain relief, but available data were insufficient for analysis of the findings. Two trials reported the secondary outcome of reduced bleeding during surgery. Bleeding during surgery was observed in nine out of 52 participants as compared with 25 out of 51 participants in the adrenaline with lidocaine and plain lidocaine groups, respectively. The risk ratio for bleeding in the adrenaline with lidocaine group was 0.35 (95% CI 0.19 to 0.65; two RCTs, 103 participants; low-quality evidence). From the limited data available, evidence is insufficient to recommend use or avoidance of adrenaline in digital nerve blocks. The evidence provided in this review indicates that addition of adrenaline to lidocaine may prolong the duration of anaesthesia and reduce the risk of bleeding during surgery, although the quality of the evidence is low. We have identified the need for researchers to conduct large trials that focus on other important outcomes such as adverse events, cost analysis and duration of postoperative pain relief.
Output:

Evidence is current to November 2014. We included studies in children (aged older than 28 days and younger than 18 years) and adult patients (aged 18 years or older) of either gender undergoing surgery on digits (fingers and toes) under nerve blocks using adrenaline with lidocaine. We found four eligible studies with 167 participants. One small study reported the duration of anaesthesia and found that adrenaline prolonged the duration of anaesthesia, but the quality of the evidence was low. No study reported on adverse events such as ischaemia distal to the injection site or cost analysis with use of adrenaline with lidocaine. Duration of postoperative pain relief was reported by one study, but available data were insufficient for analysis of the findings. Two studies reported reduced bleeding during surgery with use of adrenaline with lidocaine. In the light of our results, we would expect that 17.2 out of 100 patients who received adrenaline with lidocaine (between 8.7 and 29.8 patients) would have bleeding during surgery compared with 49 patients who would have received plain lidocaine; however, the quality of the evidence was low, and further research is very likely to impact our confidence in this estimate. The quality of evidence is low for both duration of anaesthesia and bleeding during surgery with use of adrenaline with lidocaine. Further research is needed to prove the benefits of adding adrenaline to lidocaine.