Relationship between injectate volume and disposition in erector spinae plane block: a cadaveric study

Programmed intermittent bolus versus continuous infusion for catheter-based erector spinae plane block on quality of recovery in thoracoscopic surgery: a single-centre randomised controlled trial

BACKGROUND

Regional anaesthesia techniques, including the erector spinae fascial plane (ESP) block, reduce postoperative pain after video-assisted thoracoscopic surgery (VATS). Fascial plane blocks rely on spread of local anaesthetic between muscle layers, and thus, intermittent boluses might increase their clinical effectiveness. We tested the hypothesis that postoperative ESP analgesia with a programmed intermittent bolus (PIB) regimen is better than a continuous infusion (CI) regimen in terms of quality of recovery after VATS.

METHODS

We undertook a prospective, double-blinded, randomised, controlled trial involving 60 patients undergoing VATS. All participants received ESP block catheters and were randomly assigned to CI or PIB of local anaesthetic regimen for postoperative analgesia. The primary outcome was Quality of Recovery-15 (QoR-15) score 24 h after surgery. Secondary outcomes included postoperative respiratory function, opioid consumption, verbal rating pain score, time to first mobilisation, nausea, vomiting, and length of hospital stay.

RESULTS

Overall QoR-15 scores at 24 h after VATS were similar (PIB 115.5 [interquartile range 107-125] vs CI 110 [93-128]; Δ<6, P=0.29). The only quality of recovery descriptor showing a significant difference was nausea and vomiting, which was favourable in the PIB group (10 [10-10] vs 10 [7-10]; P=0.03). Requirement for rescue antiemetics up to 24 h after surgery was lower in the PIB group (4 [14%] vs 11 [41%]; P=0.04). There were no differences in other secondary outcomes between groups.

CONCLUSIONS

Delivering ESP block analgesia after VATS via a PIB regimen resulted in similar QoR-15 at 24 h compared with a CI regimen.

Differential nerve blockade to explain anterior thoracic analgesia without sensory blockade after an erector spinae plane block may be wishful thinking

Ultrasound-guided erector spinae plane block (ESPB) is currently used as a component of multimodal analgesic regimen in a multitude of indications but the mechanism by which it produces anterior thoracic analgesia remains a subject of controversy. This is primarily the result of ESPB's failure to consistently produce cutaneous sensory blockade (to pinprick and cold sensation) over the anterior hemithorax. Nevertheless, ESPB appears to provide 'clinically meaningful analgesia' in various clinical settings. Lately, it has been proposed that the discrepancy between clinical analgesia and cutaneous sensory blockade could be the result of differential nerve blockade at the level of the dorsal root ganglion. In particular, it is claimed that at a low concentration of local anesthetic, the C nerve fibers would be preferentially blocked than the Aδ nerve fibers. However, the proposal that isolated C fiber mediated analgesia with preserved Aδ fiber mediated cold and pinprick sensation after an ESPB is unlikely, has never been demonstrated and, thus, without sufficient evidence, cannot be attributed to the presumed analgesic effects of an ESPB.

Paravertebral and erector spinae plane blocks decrease length of stay compared with local infiltration analgesia in autologous breast reconstruction

BACKGROUND

Autologous breast reconstruction is associated with significant pain impeding early recovery. Our objective was to evaluate the impact of replacing surgeon-administered local infiltration with preoperative paravertebral (PVB) and erector spinae plane (ESP) blocks for latissimus dorsi myocutaneous flap reconstruction.

METHODS

Patients who underwent mastectomy with latissimus flap reconstruction from 2018 to 2022 were included in three groups: local infiltration, PVB, and ESP blocks. Block effect on postoperative length of stay (LOS) and the association between block status and pain, opioid consumption, time to first analgesic, and postoperative antiemetic administration were assessed.

RESULTS

122 patients met the inclusion criteria for this retrospective cohort study: no block (n=72), PVB (n=26), and ESP (n=24). On adjusted analysis, those who received a PVB block had a 20-hour shorter postoperative stay (95% CI 11 to 30; p<0.001); those who received ESP had a 24-hour (95% CI 15 to 34; p<0.001) shorter postoperative stay compared with the no block group, respectively. Using either block was associated with a reduction in intraoperative opioids (23 morphine milligram equivalents (MME)), 95% CI 14 to 31, p<0.001; ESP versus no block: 23 MME, 95% CI 14 to 32, p<0.001).

CONCLUSIONS

Replacing surgical infiltration with PVB and ESP blocks for autologous breast reconstruction reduces LOS. The comparable reduction in LOS suggests that ESP may be a viable alternative to PVB in patients undergoing latissimus flap breast reconstruction following mastectomy. Further research should investigate whether ESP or PVB have better patient outcomes in complex breast reconstruction.