Central Sensitization, Chronic Postsurgical Pain, Lung Resection, Mechanical Hyperalgesia, Postoperative Pain, Thoracic Surgery
Conditions
Keywords
Quantitative sensory testing, QST, Incision pain mapping, Thoracoscopic surgery, Perioperative pain phenotype
Brief summary
Postoperative pain remains a common and clinically important burden after thoracic surgery and may progress to chronic postsurgical pain. Conventional pain assessment mainly relies on patient-reported pain intensity and analgesic consumption, which may not fully capture peri-incisional sensory abnormalities, mechanical hyperalgesia, or central sensitization. This prospective observational pilot cohort study aims to evaluate the feasibility and acceptability of perioperative quantitative sensory testing (QST) and incision pain mapping in adult patients undergoing elective thoracoscopic or robotic-assisted lung resection. Participants will undergo baseline assessment before surgery, serial postoperative pain assessments during the first 72 hours, QST and mechanical hyperalgesia pain mapping at 48-72 hours after surgery, and follow-up assessments at discharge, 1 month, and 3 months after surgery. The primary feasibility outcomes include recruitment rate, QST completion rates, follow-up completion rates, QST-related discontinuation rate, study-related adverse events, and data completeness. The main clinical mechanistic outcome is the area of peri-incisional mechanical hyperalgesia at 48-72 hours after surgery. Secondary outcomes include acute postoperative pain intensity, pain burden over 72 hours, opioid consumption, quality of recovery, QST changes, pain-map characteristics, and chronic postsurgical pain at 3 months. This study will not assign or modify therapeutic interventions. All anesthetic, surgical, and analgesic management will be determined by the routine clinical care team. The study is expected to provide feasibility data, preliminary effect estimates, and mechanistic information for future larger perioperative pain studies.
Detailed description
This is a single-center, prospective, observational pilot cohort study conducted in adult patients scheduled to undergo elective thoracoscopic or robotic-assisted lung resection. The study is designed to characterize perioperative pain phenotypes using standardized quantitative sensory testing (QST), incision-centered mechanical hyperalgesia pain mapping, serial pain intensity assessments, analgesic exposure, psychological and sleep-related questionnaires, and exploratory inflammatory or plasma biomarker measurements. Eligible participants will provide written informed consent before surgery. Baseline assessments will be performed 1-3 days before surgery and will include demographic and clinical data collection, baseline pain history, psychological and sleep-related questionnaires, preoperative QST, and blood sampling. QST will assess sensory function in the surgical-side thoracic region, contralateral mirror region, and a remote control site where applicable. During the first 72 hours after surgery, resting and movement-related numeric rating scale pain scores will be collected at prespecified time points, together with perioperative anesthetic, regional block, surgical, analgesic, and recovery-related information. Opioid consumption will be converted to morphine milligram equivalents. At 48-72 hours after surgery, participants will undergo core postoperative QST and incision-centered mechanical pain mapping. The pain map will be generated around the incision or main port site in eight radial directions. Standardized mechanical stimulation will be applied from normal surrounding skin toward the incision, and boundary points will be marked when the participant reports a transition from normal sensation to increased pain, sharpness, burning, or abnormal discomfort. These boundary points will be connected to estimate the area of mechanical hyperalgesia. Additional assessments will be performed before discharge, at 1 month, and at 90 ± 14 days after surgery. Follow-up assessments will evaluate persistent pain, pain intensity, pain interference, neuropathic pain features, QST changes, pain-map characteristics, quality of recovery, and exploratory blood biomarkers. Chronic postsurgical pain will be assessed at 3 months after surgery and defined as new or worsened pain related to the surgical area, persisting for at least 3 months after surgery, and not better explained by other causes. The study will not assign any therapeutic intervention. Surgical technique, anesthetic management, regional analgesia, postoperative analgesia, chest tube management, and perioperative care will follow routine clinical practice. Key perioperative variables will be prospectively collected and considered as potential confounders in statistical analyses.
Interventions
OTHERPerioperative QST and incision pain mapping assessment
Participants will undergo non-invasive perioperative quantitative sensory testing and incision-centered mechanical pain mapping at prespecified time points. These assessments are observational and will not determine or modify clinical anesthesia, analgesia, or surgical management.
Sponsors
Tongji Hospital
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
MALE
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
1. Male 2. Scheduled to undergo elective thoracoscopic or robotic-assisted lung resection. 3. American Society of Anesthesiologists physical status I to III. 4. Able to understand and communicate adequately and to complete study questionnaires independently or with assistance from study staff. 5. Willing to undergo QST assessment, perioperative venous blood sampling, and postoperative follow-up. 6. Able and willing to provide written informed consent.
Exclusion criteria
1. Definite chronic chest wall, shoulder, back, or upper limb pain with an average 2. Numeric Rating Scale score of 3 or higher during the preceding week. 3\. Definite painful neuropathic disease or long-term use of opioids or other analgesics for more than 2 weeks. 4\. Peripheral neuropathy, spinal cord disease, or other neurological disease that may substantially interfere with interpretation of QST results. 5\. Severe cognitive impairment, psychiatric disorder, communication disorder, or inability to complete questionnaires and QST assessments. 6\. Active infection, active autoimmune disease, or other disease condition that may substantially affect inflammatory protein measurements. 7\. Emergency surgery, conversion to open thoracotomy, extensive chest wall resection, or severe intraoperative complications. 8\. Any condition that, in the opinion of the investigator, makes the participant unsuitable for continued participation in the study.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Recruitment Rate | Baseline | Proportion of eligible patients who provide written informed consent and are enrolled in the study. |
| Completion Rate of Baseline Quantitative Sensory Testing | Preoperative period, 1 to 3 days before surgery | Proportion of enrolled participants who complete the planned baseline QST assessment before surgery. |
| Completion Rate of Postoperative QST and Incision Pain Mapping | 48 to 72 hours after surgery | Proportion of enrolled participants who complete the core postoperative QST assessment and incision-centered mechanical hyperalgesia pain mapping. |
| Completion Rate of 1-month Follow-up | 1 month after surgery | Proportion of enrolled participants who complete the planned 1-month postoperative follow-up assessment. |
| Completion Rate of 3-month Pain Outcome Follow-up | 90 ± 14 days after surgery | Proportion of enrolled participants who complete the primary 3-month postoperative pain outcome assessment. |
| QST-related Discontinuation Rate | From baseline assessment to 3 months after surgery | Proportion of participants who discontinue QST or pain mapping prematurely because of pain intolerance, fatigue, anxiety, or other participant-related reasons. |
| Study-related Adverse Event Rate | From baseline assessment to 3 months after surgery | Proportion of participants with study-related adverse events, including marked discomfort, transient pain exacerbation, local discomfort related to QST or pain mapping, or adverse events related to blood sampling. |
| Data Completeness of Key Study Variables | From baseline assessment to 3 months after surgery | Proportion of missing data for key variables |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Movement-related Pain Intensity During the First 72 Hours After Surgery | 1, 6, 12, 18, 24, 32, 40, 48, 60, and 72 hours after surgery | Movement-related pain intensity measured using an 11-point Numeric Rating Scale during turning in bed or active mobilization, where 0 indicates no pain and 10 indicates the worst imaginable pain. |
| Resting Pain Intensity During the First 72 Hours After Surgery | 1, 6, 12, 18, 24, 32, 40, 48, 60, and 72 hours after surgery | Resting pain intensity measured using an 11-point Numeric Rating Scale, where 0 indicates no pain and 10 indicates the worst imaginable pain. |
| Area of Peri-incisional Mechanical Hyperalgesia | 48 to 72 hours after surgery | Area of mechanical hyperalgesia around the surgical incision or main port site, measured in square centimeters using standardized incision-centered mechanical pain mapping. |
| Area Under the Curve of Resting Pain Scores | 0 to 72 hours after surgery | Cumulative resting pain burden calculated as the area under the curve of serial resting Numeric Rating Scale pain scores during the first 72 postoperative hours. |
| Area Under the Curve of Movement-related Pain Scores | 0 to 72 hours after surgery | Cumulative movement-related pain burden calculated as the area under the curve of serial movement-related Numeric Rating Scale pain scores during the first 72 postoperative hours |
| Cumulative Opioid Consumption | 0 to 72 hours after surgery | Total postoperative opioid consumption during the first 72 hours after surgery, converted to morphine milligram equivalents. |
| Quality of Recovery-15 Score | 72 hours after surgery and before discharge | Postoperative recovery quality assessed using the 15-item Quality of Recovery questionnaire. Higher scores indicate better recovery. |
| Analgesia-related Adverse Effects | 0 to 72 hours after surgery | Incidence of analgesia-related adverse effects, including postoperative nausea and vomiting, excessive sedation, dizziness, or other analgesia-related symptoms. |
| Time to First Ambulation | Perioperative | Time from the end of surgery to the first documented postoperative ambulation. |
| Chest Tube Duration | Perioperative | Duration of postoperative chest tube drainage, measured in hours or days. |
| Postoperative Length of Hospital Stay | Perioperative | Number of days from surgery to hospital discharge. |
| Perioperative Complications | Perioperative | Incidence of perioperative complications recorded during hospitalization |
| Change in Quantitative Sensory Testing Parameters | Baseline, 48 to 72 hours after surgery, 1 month after surgery, and 90 ± 14 days after surgery | Changes in QST parameters measured at the surgical-side thoracic region, contralateral mirror region, and remote control site when applicable. |
| Maximum Radius of Peri-incisional Pain Map | 48 to 72 hours after surgery, 1 month after surgery, and 90 ± 14 days after surgery | Maximum radial distance from the incision or main port site to the boundary of mechanical hyperalgesia. |
| Minimum Radius of Peri-incisional Pain Map | 48 to 72 hours after surgery, 1 month after surgery, and 90 ± 14 days after surgery | Minimum radial distance from the incision or main port site to the boundary of mechanical hyperalgesia. |
| Incidence of Persistent Pain at 1 Month | 1 month after surgery | Proportion of participants reporting pain related to the surgical area at 1 month after surgery. |
| Incidence of Chronic Postsurgical Pain at 3 Months | 90 ± 14 days after surgery | Proportion of participants with new or worsened pain related to the surgical area persisting at 3 months after surgery and not better explained by other causes. |
| Pain Interference at 3 Months | 90 ± 14 days after surgery | Pain-related interference with daily activity, sleep, and function assessed using the Brief Pain Inventory-short form. |
| Neuropathic Pain Features at 3 Months | 90 ± 14 days after surgery | Neuropathic pain symptoms, such as numbness, burning pain, electric shock-like pain, or touch-evoked pain, assessed using the DN4 questionnaire and symptom interview. |
Countries
China
Contacts
CONTACTNi Zhang, Dr
Outcome results
None listed