Surgery · Medical Literature
Perioperative 24-Hour Lidocaine Infusion Does Not Prevent Chronic Postthoracotomy Pain: A Triple-Blinded Randomized Controlled Trial.
Abstract
Managing chronic postsurgical pain is challenging. Evidence supporting the use of perioperative lidocaine to prevent it is inconsistent, potentially due to insufficient infusion duration. To determine the effect of extending lidocaine infusion to 24 hours for treating chronic postsurgical pain in patients undergoing video-assisted thoracoscopic surgery. Triple-blind, controlled randomized trial. A tertiary center in a university hospital. Seventy-one patients undergoing elective video-assisted thoracoscopic surgery were randomized 1:1 to receive either 2% lidocaine or placebo infusion at a speed of 4 mL/h started after anesthesia induction and continued for 24 hours. Primary outcomes were chronic postsurgical pain at 3 months defined as present pain score > 0 on an 11-point Numeric Rating Scale. Secondary outcomes included acute pain and opioid use during the first postsurgical 48 hours, and chronic postsurgical pain for up to 6 months. The incidences of chronic postsurgical pain at either 3 or 6 months did not differ significantly between the placebo and lidocaine groups (50% vs 50%, P = 1.0; 27% vs 32%, P = 0.63, respectively). There were no significant differences in acute pain scores or opioid consumption between the groups. Dizziness was more frequent during lidocaine infusion (47% vs 14% in the placebo group, P < 0.01). No serious adverse events were reported. The follow-up period was limited to 6 months and there was a small number of patients. A perioperative lidocaine infusion for 24 hours added to multimodal analgesia did not prevent chronic postthoracotomy pain.
Clinical relevance
Does extending perioperative intravenous lidocaine infusion to 24 hours, compared with placebo, reduce the incidence of chronic postsurgical pain at 3 and 6 months in patients undergoing video-assisted thoracoscopic surgery (VATS)? __SNAPSHOT__ {"studyDesign":"Triple-blind, parallel-group, randomized controlled trial (1:1 allocation)","setting":"Single tertiary university hospital; country not specified in the abstract","sampleSize":"n = 71 (lidocaine: ~36, placebo: ~35; exact per-arm allocation not stated in abstract)","population":"Adults undergoing elective video-assisted thoracoscopic surgery (VATS); specific inclusion/exclusion criteria beyond elective VATS not reported in the abstract","intervention":"2% lidocaine intravenous infusion at 4 mL/h (approximately 80 mg/h), initiated after anesthesia induction and continued for 24 hours postoperatively","comparator":"Matching placebo (presumed normal saline) infusion at 4 mL/h for 24 hours","primaryOutcome":"Incidence of chronic postsurgical pain (CPSP) at 3 months, defined as a Numeric Rating Scale (NRS, 0–10) score > 0","followUp":"6 months (CPSP assessed at 3 and 6 months; acute pain and opioid use assessed over the first 48 hours postoperatively)","fundingSource":"Not reported"}
Key findings
The primary outcome — incidence of CPSP at 3 months — was identical between groups: 50% in both the placebo and lidocaine arms (P = 1.0). At 6 months, CPSP incidence was 27% (placebo) vs. 32% (lidocaine), which was also not statistically significant (P = 0.63). The absolute risk difference for the primary outcome was 0 percentage points (calculated), and the NNT is not calculable given no observed benefit. The abstract reports no significant differences in acute pain scores or opioid consumption during the first 48 postoperative hours, although specific numeric values (means, standard deviations, confidence intervals) for these secondary outcomes were not reported in the available abstract text. Adverse event data were not reported in the provided abstract. The CPSP incidence of 50% at 3 months in both groups is consistent with reported rates following VATS and thoracotomy procedures.
Practice implications
This RCT provides direct evidence that extending perioperative intravenous lidocaine infusion to 24 hours does not reduce the incidence of chronic postsurgical pain at 3 or 6 months following VATS, nor does it appear to reduce acute postoperative pain or opioid use within the first 48 hours. The study's rationale was based on the hypothesis that shorter infusion durations in prior trials may have been responsible for inconsistent results; this trial refutes that specific hypothesis for the 24-hour duration in the VATS context. However, several important caveats apply: (1) Only an abstract was available for full review — complete outcome data, adverse event profiles, per-protocol analyses, and sensitivity analyses cannot be evaluated. (2) The sample size (n = 71) is small and may have been underpowered to detect modest but clinically meaningful differences; the study's power calculations and target effect size are not reported in the abstract. (3) Findings apply specifically to elective VATS patients; generalizability to open thoracotomy, higher-risk populations, or patients with preoperative pain is uncertain. (4) The CPSP definition (NRS > 0) is a low threshold with high sensitivity but potentially poor specificity for clinically meaningful chronic pain — it may inflate CPSP incidence and reduce between-group discrimination. (5) The 6-month CPSP rate numerically favored placebo (27% vs. 32%), which, although not significant, does not suggest a trend toward benefit. Taken together, the results do not support the use of 24-hour perioperative intravenous lidocaine infusion for CPSP prevention in this surgical population. __LIMITATIONS__ Small sample size (n = 71): likely underpowered to detect clinically modest but important differences; power calculations not reported in the abstract.,Single-center design limits generalizability to other institutions and health systems.,CPSP defined as NRS > 0 — an extremely low threshold that may misclassify trivial or transient discomfort as chronic pain, potentially inflating overall CPSP rates and reducing the ability to detect between-group differences.,Only an abstract is available; full outcome data, covariate adjustment, per-protocol analyses, dropout rates, and adverse event reporting cannot be assessed.,The abstract is truncated — secondary outcome results (acute pain NRS scores, opioid consumption data) are incompletely reported, preventing full effect size assessment.,Single infusion regimen tested (4 mL/h of 2% lidocaine for 24 hours); results may not generalize to different dosing strategies, infusion rates, or durations.,No multimodal analgesia context is specified — the background analgesic regimen, use of regional techniques, or other co-interventions are not described, which could significantly confound results.,Funding source not reported, precluding assessment of potential conflicts of interest.,Country not reported; contextual factors such as baseline opioid use patterns and standard of care may affect generalizability.,6-month CPSP data numerically favored placebo (27% vs. 32%), raising the possibility of a signal in the unexpected direction, though this is not statistically significant and may reflect chance in a small sample. __BOTTOM_LINE_CATEGORY__ not_ready_for_clinical_application __BOTTOM_LINE__ A 24-hour perioperative intravenous lidocaine infusion did not reduce chronic postsurgical pain incidence at 3 or 6 months, nor acute postoperative pain or opioid use within 48 hours, in patients undergoing elective VATS. Given the small sample size, single-center design, low-threshold CPSP definition, and availability of only the abstract, definitive conclusions cannot be drawn and this strategy cannot be recommended for routine CPSP prevention in VATS patients on the basis of this trial alone. Larger, adequately powered, multicenter trials with more precise CPSP definitions are needed before clinical practice is modified.