Statistically significant but clinically unimportant: a systematic review and meta-analysis of the analgesic benefits of erector spinae plane block following breast cancer surgery

Abstract

The novel erector spinae plane block (ESPB) has been reported to provide important postoperative analgesic benefits following a variety of truncal and abdominal surgical procedures. However, evidence of its analgesic efficacy following breast cancer surgery, compared with parenteral analgesia, is unclear. This meta-analysis evaluates the analgesic benefits of adding ESPB to parenteral analgesia following breast cancer surgery.Databases were searched for breast tumor resection trials comparing ESPB to parenteral analgesia. The two co-primary outcomes examined were 24-hour postoperative oral morphine equivalent consumption and area-under-curve of rest pain scores. We considered reductions equivalent to 3.3 cm.h and 30 mg oral morphine in the first 24 hours postoperatively for the two co-primary outcomes, respectively, to be clinically important. We also assessed opioid-related side effects and long-term outcomes, including health-related quality of life, persistent postsurgical pain and opioid dependence. Results were pooled using random effects modeling.Twelve trials (699 patients) were analyzed. Moderate quality evidence suggested that ESPB decreased 24-hour morphine consumption and area-under-curve of rest pain by a mean difference (95% CI) of −17.60 mg (−24.27 to −10.93) and -2.74 cm.h (−3.09 to −2.39), respectively; but these differences were not clinically important. High-quality evidence suggested that ESPB decreased opioid-related side effects compared with parenteral analgesia by an OR (95% CI) of 0.43 (0.28 to 0.66). None of the studies evaluated long-term block benefits.Adding ESPB to parenteral analgesia provides statistically significant but clinically unimportant short-term benefits following breast cancer surgery. Current evidence does not support routine use of ESPB. Given the very modest short-term benefits and risk of complications, the block should be considered on a case-by-case basis.

Use of ultrasound guided single shot costotransverse block (intertransverse process) in breast cancer surgery: a prospective, randomized, assessor blinded, controlled clinical trial

“…It is thought that the effect mechanism of ESPB in breast surgery is spread of the LA anteriorly [ 5 ]. Although studies have reported that ESPB is almost as effective as PVB for analgesia in this patient group [ 12 ], the statistically significant effect of ESPB on reducing postoperative opioid requirement has been deemed as “clinically non-important” by authors of a meta analysis [ 13 ]. Studies demonstrating the opposite have also been reported [ 14 ].…”

Erector spinae plane block for spinal surgery: a systematic review and meta-analysis

“…We evaluated the analgesic effect of ESPB in this study in a more comprehensive way in terms of multiple metrics, including pain scores in different states, cumulative perioperative opioid consumption, time to first rescue analgesic, and number of patients requiring rescue analgesia. Moreover, to boost validity and perform an accurate and less-biased assessment of the effect of ESPB [ 28 ], we only compared the ESPB group with the unblocked control group.…”

Does Inhaled Methoxyflurane Implement Fast and Efficient Pain Management in Trauma Patients? A Systematic Review and Meta-Analysis

“…The strengths of this meta-analysis include a pre-registered protocol, the comprehensive search strategy, and conservative GRADE assessment of certainty of evidence. The results were cautiously interpreted in the context of clinically important differences [32,55,56], allowing a meaningful estimate of the efficacy of methoxyflurane. Additionally, the adjusted statistical threshold for primary outcomes served to reduce the risk of type I error and multiple testing bias [32,38].…”

“…The results were cautiously interpreted in the context of clinically important differences [32,55,56], allowing a meaningful estimate of the efficacy of methoxyflurane. Additionally, the adjusted statistical threshold for primary outcomes served to reduce the risk of type I error and multiple testing bias [32,38]. Finally, the sensitivity analysis, by excluding a study with potential multiple risks (e.g., industry-sponsored), revealed that the effect estimates were robust, as the excluded data did not significantly influence the initial analysis.…”

“…There were two types of pain score definitions: visual analogue scale (VAS) that ranged from 0 to 100, 0 corresponding to no pain and 100 representing the worst imaginable pain; numeric rating scale (NRS) that ranged from 0 to 10, 0 = no pain and 10 = unbearable pain. Pain intensities of all included studies were presented as a 10-point scale (0, no pain; 10, worst pain) by simple transformations [31,32].…”