A retrospective pooled analysis conducted at the University Medical Center of the University of Medicine and Pharmacy at Ho Chi Minh City has mapped the perioperative analgesic outcomes of two erector spinae plane block techniques against both an unblocked negative control and thoracic paravertebral block, the traditional reference technique for thoracic surgical pain. Published in Frontiers in Medicine, the investigation evaluated one hundred adult patients undergoing elective video-assisted thoracoscopic surgery lobectomy across two sequential prospective clinical trials. The researchers observed that while an ultrasound-guided postoperative single-shot erector spinae plane block substantially decreased cumulative opioid needs compared to no regional block, a preoperative catheter-based erector spinae plane block using programmed intermittent bolus delivery maintained sustained analgesia across the first postoperative day with opioid consumption only slightly higher than thoracic paravertebral block delivered via the same intermittent regimen.

Acute pain following minimally invasive thoracic procedures such as video-assisted thoracoscopic lobectomy is frequently severe and can persist for multiple days if unmanaged. Insufficient postoperative analgesia impairs ventilatory mechanics, elevates the incidence of pulmonary complications, causes profound patient discomfort, and increases susceptibility to chronic postsurgical pain syndromes.

Despite widespread clinical interest, the comparative role of the erector spinae plane block has remained ambiguous due to heterogeneous study designs and fragmented evidence. To prolong analgesic duration, clinicians developed continuous catheter-based infusions and automated programmed intermittent bolus regimens, with recent anatomic and clinical data suggesting that intermittent boluses achieve wider and more consistent spread within the fascial plane than continuous low-rate infusions. Furthermore, uncertainty has persisted regarding whether administering blocks preemptively before surgical incision produces meaningful intraoperative opioid-sparing benefits compared to blocks placed upon surgical closure.

To contextualize these differing procedural variables within a structured spectrum of care, the Vietnamese investigative team compiled per-protocol clinical datasets from two consecutive prospective non-randomized trials conducted over a four-year window from 2022 through 2025. The initial trial, executed between 2022 and 2023, allocated fifty patients to either negative control care receiving no regional block or an intervention receiving a postoperative single-shot erector spinae plane block administered immediately after surgical closure. The subsequent trial, carried out between 2024 and 2025, evaluated another fifty completed procedures allocated to either a preoperative erector spinae plane block or a preoperative thoracic paravertebral block, with both cohorts managed postoperatively using programmed intermittent boluses of local anesthetic delivered through automated ambulatory infusion pumps.

Eligible study participants were adults aged eighteen to seventy-five years with American Society of Anesthesiologists physical status classifications ranging from one to three who were scheduled for elective video-assisted thoracoscopic lobectomy. Exclusion criteria barred individuals requiring emergency or elective conversion to open thoracotomy, non-lobectomy resections, postoperative invasive mechanical ventilation, reoperation within forty-eight hours, chronic opioid therapy or chronic pain conditions persisting longer than three months preoperatively, and contraindications to percutaneous block placement such as coagulopathy or localized insertion site infections. Because surgical conversion or procedural changes altered the analgesic demands beyond the target population, twenty-three of seventy-three enrolled patients in the second prospective trial were excluded following allocation based on objective operative records, ensuring that all four analyzed groups of twenty-five patients comprised uniformly completed thoracoscopic lobectomies.

All percutaneous regional nerve blocks were executed by experienced anesthesiologists with documented procedural volumes exceeding fifty prior cases for each respective technique. Ultrasound visualization utilized a high-frequency linear transducer placed in a parasagittal plane approximately three centimeters lateral to the fifth thoracic spinous process. For erector spinae plane blocks, an eighteen-gauge Tuohy needle was advanced in-plane in a caudal-to-cephalad trajectory until bone contact was established with the transverse process, with plane entry verified by hydrodissection using saline to demonstrate muscular lifting. In the single-shot group, fifteen milliliters of 0.2 percent ropivacaine, equating to thirty milligrams, was injected at wound closure. In the intermittent bolus cohorts, twenty-gauge catheters were threaded three to four centimeters into the respective target tissue planes, receiving a pre-incisional loading dose of fifteen milliliters of 0.5 percent ropivacaine, equivalent to seventy-five milligrams, followed by automated pump-delivered boluses of fifteen milliliters of 0.2 percent ropivacaine every six hours without baseline background infusion.

General anesthesia was strictly standardized across both study cohorts using double-lumen endotracheal intubation, lung-protective mechanical ventilation with positive airway pressures maintained below clinical safety thresholds, and sevoflurane maintenance titrated to a minimum alveolar concentration of approximately 1.0. All patients received an identical multimodal analgesic foundation incorporating one gram of intravenous paracetamol every six hours alongside thirty milligrams of ketorolac every eight hours, substituting twenty milligrams of nefopam when nonsteroidal anti-inflammatory drugs were contraindicated. Rescue analgesia intraoperatively was prompted whenever mean arterial blood pressure or heart rate escalated more than thirty percent above recorded baseline, delivering identical intravenous fentanyl doses of one microgram per kilogram. Postoperatively, the early trial utilized patient-controlled intravenous fentanyl delivering ten-microgram boluses with ten-minute lockout intervals, whereas the second trial transitioned to nurse-titrated intravenous morphine boluses of one milligram for visual analog scale pain scores of four or greater, standardizing both unit dose potency and minimum redosing windows to one intravenous morphine milligram equivalent.

The study established two co-primary endpoints: total intraoperative fentanyl consumption normalized to patient body mass in micrograms per kilogram, and cumulative twenty-four-hour postoperative intravenous morphine milligram equivalents recorded across scheduled intervals at one, two, six, twelve, and twenty-four hours. Intraoperative measurements revealed that patients in the preoperative catheter cohorts, comprising both erector spinae plane block and thoracic paravertebral block, consumed an average of 3.8 ± 1.0 micrograms per kilogram of fentanyl. This requirement was significantly lower than the combined mean of 4.5 ± 0.9 micrograms per kilogram documented among patients in the earlier trial who underwent surgical incision without a functioning regional block in place, yielding an overall statistically significant difference with a p-value of 0.001. No statistically significant divergence in intraoperative fentanyl consumption was identified between the preoperative erector spinae and paravertebral techniques.

Cumulative postoperative opioid requirements over the initial twenty-four postoperative hours demonstrated marked, progressive divergence across the four clinical strategies. The unblocked negative control group recorded a mean cumulative requirement of 35.7 milligrams of intravenous morphine equivalents, which dropped substantially to 10.6 milligrams in the postoperative single-shot erector spinae plane group, 4.2 milligrams in the preoperative intermittent bolus erector spinae plane group, and 1.9 milligrams in the thoracic paravertebral block cohort. Within the first trial, the single-shot technique reduced twenty-four-hour opioid requirements relative to no block by an unadjusted mean difference of negative 25.1 milligrams, confirming significant early opioid sparing. Within the contemporaneous second trial, patients receiving programmed intermittent erector spinae boluses required a mean of 2.4 milligrams more morphine equivalents than those receiving paravertebral boluses over twenty-four hours, an increment that reached statistical significance with a p-value of 0.003 but remained well below the ten-milligram threshold established as the minimal clinically important difference.

Secondary pain intensity assessments utilizing visual analog scales captured resting and dynamic pain scores during voluntary coughing, illustrating clear temporal differences between single-shot and intermittent catheter delivery. During the first two postoperative hours, resting pain scores were similarly low across all regional block cohorts, averaging between 2.0 and 3.1, compared to scores exceeding 4.0 in unblocked controls. However, by six hours and continuing through twelve and twenty-four hours, resting pain scores in the single-shot cohort increased significantly, averaging 3.8, while scores in the intermittent catheter cohorts remained suppressed at 2.4 for erector spinae catheters and 2.0 for paravertebral catheters. Dynamic pain during coughing displayed an analogous pattern, where pain scores converged between both catheter groups from two hours onward, having differed significantly only at the initial one-hour assessment where paravertebral block provided superior dynamic suppression.

Tertiary safety assessments revealed no occurrences of local anesthetic systemic toxicity, pneumothorax, excessive sedation, or inadvertent pleural puncture in any study participant, while two patients in the paravertebral group experienced vascular punctures without clinical sequelae. Overall postoperative adverse outcomes, including nausea, vomiting, respiratory failure, pneumonia, reoperation, and total length of hospital stay, showed no statistically significant differences across the four study arms, although the authors emphasized that small group sizes of twenty-five patients lacked statistical power to detect meaningful differences in rare complications. Nausea occurred in sixteen percent of unblocked controls, eight percent of both erector spinae groups, and four percent of the paravertebral cohort, paralleling the broader reductions observed in postoperative systemic opioid consumption.

The study authors highlighted several methodological limitations inherent to pooled retrospective analyses of sequential trials, explicitly advising against interpreting the findings as evidence of clinical noninferiority or as justification for displacing thoracic paravertebral block in standard practice. Because the two underlying trials were non-randomized, lacked allocation concealment, and incorporated open-label assessments in the initial phase, selection and performance biases cannot be excluded. Furthermore, because block timing, intermittent catheter technology, operational trial epoch, and systemic rescue drug delivery protocols shifted concurrently across the study phases, cross-trial differences reflect bundled institutional strategies rather than isolated pharmacologic or technical variables. Consequently, the researchers concluded that while programmed intermittent bolus erector spinae plane block represents a biologically plausible, opioid-sparing regional technique, formal confirmation of its therapeutic equivalence requires an adequately powered, randomized, prospective noninferiority trial utilizing identical postoperative rescue regimens across all concurrent study arms.

Subject of Research: Regional analgesia techniques and opioid consumption after video-assisted thoracoscopic lobectomy

Article Title: Positioning single-shot and programmed intermittent bolus erector spinae plane block for analgesia in video-assisted thoracoscopic lobectomy: a retrospective pooled analysis of two sequential prospective trials with negative and positive controls

Article References: Hung, H. Q., Tran, T. N. B., Phuc, L. T. N., Phat, T. T., Bang, H. T., Vu, P. T. N., & Dao, N. T. N. (2026). Positioning single-shot and programmed intermittent bolus erector spinae plane block for analgesia in video-assisted thoracoscopic lobectomy: a retrospective pooled analysis of two sequential prospective trials with negative and positive controls. Frontiers in Medicine, 13, Article 1935587. https://doi.org/10.3389/fmed.2026.1935587

Image Credits: AI Generated

DOI: 10.3389/fmed.2026.1935587

Keywords: erector spinae plane block, thoracic paravertebral block, video-assisted thoracoscopic surgery, VATS lobectomy, postoperative analgesia, opioid consumption, programmed intermittent bolus, single-shot nerve block, fentanyl, morphine milligram equivalents, multimodal analgesia, regional anesthesia, thoracic surgery, ropivacaine, visual analog scale, pain management