Newer Nerve Block Matches Standard Technique for Pain and Lung Recovery in Rib Fracture Patients

Patients with multiple broken ribs often struggle to breathe deeply and cough effectively, because every breath moves the fractured chest wall and pain suppresses the effort. Effective analgesia is therefore essential to preserve respiratory function in these injuries. A new randomized trial, published in BMC Anesthesiology, compared a newer ultrasound-guided regional anesthetic technique, the rhomboid intercostal–subserratus (RISS) plane block, against the established thoracic paravertebral block (TPVB) in adults with traumatic multiple rib fractures, and found the two approaches delivered closely similar results.

The study was a prospective, randomized, blinded trial conducted in a single emergency ICU. Fifty adults aged 18 to 60 years with unilateral fractures of three or more ribs were randomized one-to-one to receive either a continuous ultrasound-guided TPVB or a continuous RISS block with catheter infusion, in addition to standardized systemic analgesia. The primary endpoint was pulmonary function at 24 hours, assessed using forced expiratory volume in one second (FEV1). Secondary outcomes included pain scores at rest and during coughing, pulmonary function, diaphragmatic excursion, rescue opioid consumption, adverse events, and lengths of ICU and post-ICU ward stay.

The primary result showed no meaningful difference between the techniques. At 24 hours, FEV1 rose from 56.2 ± 3.2 percent to 72.8 ± 5.4 percent in the TPVB group and from 57.7 ± 3.0 percent to 73.8 ± 5.6 percent in the RISS group. The baseline-adjusted between-group difference was 0.47 percentage points, with a 95 percent confidence interval of −2.63 to 3.57 and a p value of 0.768, meaning the difference was not statistically significant. Pain control was likewise comparable: at 24 hours, median visual analogue scale pain scores at rest were 1 (interquartile range 0–2) in the TPVB group and 0 (0–2) in the RISS group, while scores during coughing were 3 (2–4) and 2 (2–4), respectively.

Opioid requirements also matched between the groups. Total rescue morphine consumption over 72 hours was 13.3 ± 3.2 mg in the TPVB group versus 11.7 ± 4.6 mg in the RISS group, a difference that was not statistically significant (p = 0.205). One technical measure did favor the newer block: needle visibility was significantly better with the RISS approach, which may matter for practitioners learning the technique or for patients in whom an easier, more clearly visualized injection is advantageous.

Complications were observed only in the TPVB group: vascular puncture and block-related pneumothorax each occurred in two TPVB patients and in no RISS patients. However, the trial’s authors are careful to note that these between-group differences were not statistically significant, and the trial was not powered to establish comparative safety. The authors conclude that continuous ultrasound-guided RISS block provided analgesia and 24-hour pulmonary-function recovery similar to TPVB in stable, spontaneously breathing patients with unilateral multiple rib fractures, while also offering better needle visibility. The findings apply to the specific population studied—stable, spontaneously breathing adults with unilateral fractures of three or more ribs treated in a single center—and the trial was retrospectively registered with ClinicalTrials.gov (NCT05898958). For clinicians weighing which block to choose at the bedside, the trial suggests the newer RISS technique is a reasonable alternative to the thoracic paravertebral approach, with comparable analgesia and respiratory recovery, though larger studies would be needed to draw firm conclusions about complication rates.

Subject of Research: Comparison of two ultrasound-guided regional nerve blocks for analgesia and respiratory recovery after multiple rib fractures

Article Title: Continuous ultrasound-guided rhomboid intercostal–subserratus plane block versus thoracic paravertebral block for analgesia and respiratory recovery in patients with multiple rib fractures: a single-center randomized trial

Article References: Ahmed El-Tohamy, S., Elharrisi, M. A., Mansour, A. R., & Elshafei, A. S. (2026). Continuous ultrasound-guided rhomboid intercostal–subserratus plane block versus thoracic paravertebral block for analgesia and respiratory recovery in patients with multiple rib fractures: a single-center randomized trial. BMC Anesthesiology. https://doi.org/10.1186/s12871-026-04339-0

Image Credits: AI Generated

DOI: 10.1186/s12871-026-04339-0

Keywords: rib fractures, regional anesthesia, rhomboid intercostal–subserratus block, thoracic paravertebral block, ultrasound-guided block, pain management, FEV1, randomized trial, respiratory function, emergency ICU, analgesia, catheter infusion