Programmed intermitent bolus infusion in paravertebral catheter for the control of pain after thoracic surgery: a systematic review and meta-analysis

Position du problème et objectif(s) de l’étude

Thoracic surgery, including thoracotomy and video-assisted thoracoscopic surgery (VATS), is associated with significant postoperative pain, which may progress to chronic pain in some patients. Paravertebral block (PVB) is a recognized alternative to thoracic epidural analgesia, offering comparable efficacy with fewer adverse effects. While continuous infusion of local anesthetics via a paravertebral catheter is the most common technique, programmed intermittent bolus infusion (PIBI) may enhance drug spread and dermatomal coverage, as shown in obstetric anesthesia. Objectif : To compare the analgesic efficacy of PIBI with that of continuous infusion (CI) via a paravertebral catheter in thoracic surgery, through a meta-analysis of randomized controlled trials.

Matériel et méthodes

A systematic review was conducted in accordance with PRISMA guidelines (PROSPERO: CRD42024581623). PubMed and Cochrane databases were searched without date restrictions. Randomized controlled trials comparing PIBI and CI in thoracic surgery were included. The primary outcome was pain intensity (Numeric Rating Scale, 0–10) at 24 hours postoperatively, at rest and during coughing. Secondary outcomes included pain scores at 1, 12, and 48 hours, and the number of dermatomes anesthetized at 24 hours. Statistical analysis was performed using RevMan 5.4 with a random-effects model. Heterogeneity was assessed using the I² statistic. When necessary, medians were converted to means ± standard deviations according to Cochrane methods.

Résultats & Discussion

Of 607 references screened, eight studies were included. At 24 hours, no significant difference in pain scores was observed between PIBI and CI, either at rest (weighted mean difference [WMD]: –0.04; 95% CI: –0.53 to 0.44) or during coughing (WMD: 0.18; 95% CI: –0.71 to 1.08). Similarly, no differences were found at 1, 12, or 48 hours. However, PIBI was associated with significantly greater dermatomal spread at 24 hours (WMD: +1.53 dermatomes; 95% CI: 0.72 to 2.34; p = 0.0002). This finding, although not directly correlated with pain scores, is consistent with experimental data suggesting that intermittent bolus injections can generate transiently higher pressures that favor wider spread along the paravertebral gutter. Substantial heterogeneity was present across studies (I² > 80%), mainly due to differences in local anesthetic protocols, including the type of drug (ropivacaine, bupivacaine, levobupivacaine), concentrations, infusion rates, bolus volumes, and use of patient-controlled boluses. Additionally, none of the included studies clearly reported or standardized the timing of chest drain removal, despite the fact that thoracic drains are a major source of postoperative pain, particularly during coughing or deep breathing. The lack of this information represents a potential confounding factor that may have influenced pain assessments. Finally, most studies focused solely on subjective pain scores, without evaluating functional recovery or patient satisfaction, thus limiting the overall interpretation of analgesic efficacy.

Conclusion

This meta-analysis did not demonstrate superior postoperative analgesia with PIBI compared to continuous infusion. Nonetheless, the broader dermatomal distribution observed with PIBI suggests enhanced anesthetic spread, though its clinical relevance remains uncertain. Well-designed multicenter trials with standardized protocols and recovery-focused endpoints are needed to better define the role of PIBI in thoracic analgesia.

Auteurs

Berengere BORRELLY, Philippe GUERCI, Emmanuel NOVY, Nicolas VAUTRIN, Joseph SEITLINGER, Stéphane RENAUD, Arthur STREIT - (1)Chru Nancy-Hopital De Brabois, Nancy, France

Orateur(s)

Berengere BORRELLY (Nancy)