Clinical mechanisms of continuous stellate ganglion block in improving postoperative anxiety and depression after thoracoscopic lung cancer surgery

Abstract

BACKGROUND

To investigate the effects of continuous stellate ganglion block (CSGB) on anxiety and depression in patients after thoracoscopic lung cancer surgery, and to analyze its potential clinical mechanisms and relationship with postoperative pain, sleep quality, and recovery progress.

AIM

To assess the effect of CSGB on postoperative anxiety and depression after thoracoscopic lung cancer surgery.

METHODS

A retrospective analysis included 135 patients who underwent thoracoscopic lung cancer resection at a tertiary hospital from January 2021 to December 2023. The CSGB group (n = 65) received CSGB treatment postoperatively, while the control group (n = 70) did not receive CSGB intervention. Self-Rating Anxiety Scale (SAS) and Self-Rating Depression Scale (SDS) scores were collected preoperatively and on postoperative days 1, 3, and 7. Visual Analog Scale (VAS) for pain, Pittsburgh Sleep Quality Index, time to first ambulation, chest tube removal time, postoperative hospital stay, and complications were recorded. Logistic regression analyzed independent risk factors for anxiety and depression, and Pearson correlation assessed the relationship between pain and emotional states.

RESULTS

SAS and SDS scores on postoperative days 3 and days 7 were significantly lower in the CSGB group compared to controls (P < 0.01). VAS scores were also markedly reduced, Pittsburgh Sleep Quality Index scores improved, and time to first ambulation, chest tube removal time, and hospital stay were significantly shortened (P < 0.05). Logistic regression showed that poor postoperative pain control was an independent risk factor for anxiety and depression (odds ratio = 2.34, P < 0.05). Pearson analysis revealed positive correlations between VAS scores and SAS/SDS scores (r = 0.62, P < 0.01). The CSGB group also had lower incidence of complications such as nausea, vomiting, and arrhythmias compared to controls (P < 0.05).

CONCLUSION

CSGB effectively alleviates anxiety and depression in patients after thoracoscopic lung cancer surgery. The mechanisms may involve improved postoperative pain control, regulation of sympathetic nervous system function, and enhanced sleep quality. CSGB has potential dual physical and psychological intervention value in postoperative rapid recovery and warrants further clinical promotion.

Key Words: Stellate ganglion block; Thoracic surgery; Video-assisted; Lung neoplasms; Postoperative anxiety; Postoperative pain

Core Tip: In this study, we demonstrated that continuous stellate ganglion block (CSGB) was more effective than sham-CSGB in reducing postoperative anxiety and depression in patients with thoracoscopic lung cancer surgery. In summary, CSGB has dual physical-psychological benefits through the modulation of sympathetic nervous system, surgical pain relief, sleep quality improvement and early mobilization. CSGB emerges as a potential adjunct within enhanced recovery pathways, providing an innovative opportunity for optimal physiological and emotional outcomes and earlier postoperative recovery.

INTRODUCTION

Lung cancer is one of the most common and deadly types of malignant tumor in the world, especially in Asian countries where it incurs a rising incidence each year[1,2]. Recently, lung cancer is leading in both incidence and mortality among all malignant tumors in China according to epidemiological data[2], with non-small cell lung cancer (NSCLC) comprising more than 80% of total lung cancers[3]. Due to its minimal trauma, short recovery and fewer postoperative complications, video-assisted thoracoscopic surgery has become the standard method for early NSCLC resection[4,5]. Nevertheless, although thoracoscopic surgery has matured with technological advancements leading to reduced postoperative pain, sleep disorders and psychosocial factors still play a significant role in determining the quality of recovery after surgery[6]. These undesirable responses result in extended hospital stay, amplified health-care expenditure but they can also influence patients' long-term quality of life and prognosis[7].

Psychiatric illness, especially anxiety and depression, is common after thoracic surgery in general but most clear-cut among patients with lung cancer. Research indicates that nearly 30%-50% of patients who undergo thoracic surgery have varying degrees of anxiety and depression, which is closely related to chronic pain, weakened immune function, extended hospitalization period and quality of life downgrade in the postoperative stage[8,9]. Postoperative pain, a physiological stressor, is also an important inciter of both anxiety and depression[10]. Not only does effective analgesia facilitate recovery of the physiologic response, but it also has benefits for psychological resilience. Surgical trauma, anesthetic agents, interruption of normal metabolism, postoperative complications such as alarm pain[6], worries of tumor recurrence or metastasis, and economic burden can increase psychological pressure on patients and cause and sustain anxiety[7,8] or depression[9-11].

Stellate ganglion block (SGB) is a kind of regional block that perfused local anesthetics to the cervical sympathetic ganglia, which allows modulating the balance between the sympathetic and parasympathetic nervous system. This technique was originally mainly performed to treat head and neck pain, complex regional pain syndrome and peripheral vascular diseases[12]. In consecutive years SGB has been shown to be effective for postoperative analgesia, sleep and emotional regulation, with further indications reported in other psychiatric conditions such as post-traumatic stress disorder, anxiety disorders, and depression[13,14]. Continuous sympathetic block provides prolonged duration of sympathetic blockade with infusion of local anesthetics, whereas continuous SGB (CSGB) seems to be involved more actively in the early postoperative setting.

There are few mechanisms and studies on thoracoscopic lung cancer surgical colonization of the effect of CSGB on anxiety and depression. This study retrospectively analyzed the ameliorative effects of CSGB on not only the level of postoperative anxiety but also depression and preliminary clinical mechanisms to provide new ideas and evidence for rapid recovery and postoperative psychological intervention. We hypothesize that CSGB, by inhibiting sympathetic conduction, diminishes sympathetic excitability and stress responses explaining favorable postoperative pain outcomes related to anxiety. Meanwhile, CSGB may modulate hypothalamic-pituitary adrenal (HPA) axis function, decrease cortisol levels and ameliorate emotional states[15]. Besides, CSGB might indirectly affect central nervous system function by increasing carotid blood flow and thus by enhancing sleep quality and emotional stability.

These results may offer novel approaches for psychological intervention in patients with lung cancers who will undergo thoracoscopic procedures. Postoperative rapid recovery and quality of life can be facilitated through optimal analgesic protocols, which could improve emotional states. CSGB may play a vital role in multimodal analgesia and psychological intervention for thoracic surgery in the future, providing more effective treatment experiences and prognosis for patients with lung cancer.

MATERIALS AND METHODS

Study design

This is a retrospective study according to the patients who underwent thoracoscopic lung cancer surgery in single-center thoracic surgery department from January 2021 to December 2023. Clinical data were collected through the electronic medical record system and patients were divided into CSGB and control groups depending on whether they received CSGB postoperatively. The study was registered after following the STROBE retrospective study reporting standards and approved by the ethics committee of the hospital (approval No. K2025129) with waiver of patient informed consent.

Study subjects

Inclusion criteria: Age 18-75; American Society of Anesthesiologists grade I-III; pathologically and cytological confirmed NSCLC; elective thoracoscopic lobectomy/segmentectomy; preoperative Self-Rating Anxiety Scale (SAS) and Self-Rating Depression Scale (SDS) scores within normal range; complete clinical data.

Exclusion criteria: Preoperative history of psychiatric disorders (e.g., anxiety, depression) or medication use that could lead to confounding; intraoperative conversion to open thoracotomy; postoperative severe complication (e.g., respiratory failure; atelectasis); neck surgery or radiation therapy history; coagulation disorder and localized infection or puncture contraindication.

Sample size and grouping

A total of 135 patients meeting inclusion criteria were included, with 65 in the CSGB group and 70 in the control group. In order to reduce the influence of the confounding factors at baseline, 1:1 propensity score matching (PSM) was applied, by matching age, gender, body mass index (BMI), tumor stage, surgical method and operative time with a caliper of 0.02. Each variable compared between groups showed no statistical difference (P > 0.05) establishing comparability.

Intervention measures

Patients in the CSGB group who underwent ultrasound-guided CSGB immediately after surgery. Patients were placed in a supine position head turned to the side of intervention with routine sterile preparation and draping. In the left lateral position, a high-frequency linear array probe (6-13 MHz) was placed to locate the space between carotid sheath and thyroid on C6-C7. A 22G puncture needle was advanced under real-time ultrasound guidance to the location on surface of longus colli muscle. Following negative aspiration for blood and fluid, a loading 5 mL of 0.2% ropivacaine was injected at L3-4, followed by insertion of a 20G epidural catheter. After fixation, the catheter was linked to an analgesic pump that permitted continuous infusion of 0.2% ropivacaine at 2 mL/hour for a total of 48 hours. Control: No nerve block; routine postoperative analgesia included patient-controlled intravenous analgesia and non-steroidal anti-inflammatory drugs.

Data collection

The following data were collected through the hospital electronic medical record system and postoperative follow-up records: (1) General information: Age, sex, BMI, smoking history, comorbidities, tumor stage, surgical method, operative time, intraoperative blood loss; (2) Emotional assessment: Zung SAS and SDS were performed 1 day preoperatively and on postoperative days 1, 3, and 7, with scores ≥ 50 indicating anxiety/depression; (3) Pain assessment: Visual Analog Scale (VAS) on a 0-10 scale, recording pain intensity at rest and during movement on postoperative days 1, 3, and 7; (4) Sleep quality: Pittsburgh Sleep Quality Index (PSQI) assessed preoperatively and on postoperative day 7, with total score ≥ 7 suggesting poor sleep quality; (5) Recovery indicators: Time to first ambulation, chest tube removal time, postoperative hospital stay; and (6) Complications: Occurrence of postoperative nausea and vomiting, arrhythmias, pulmonary infections, subcutaneous emphysema.

Statistical analysis

Statistical analysis was conducted using the software SPSS 26.0. Normally distributed continuous data were presented as mean ± SD and compared using independent samples t-test between the groups values of non-normally distributed data were expressed as median (interquartile range), and Mann-Whitney U test was used. Categorical data were presented as n (%), and compared between groups with the use of χ² test or Fisher’s exact test when appropriate. The intergroup differences of SAS, SDS, and VAS scores across different time points were compared with repeated measures analysis of variance. Methods logistic regression was performed to identify independent risk factors for postoperative anxiety and depression, including analysis of variables such as age, gender, operative time, intraoperative blood loss and VAS scores results. Utilizing Pearson correlation analysis, VAS scores among SAS/SDS scores were assessed. All tests were two-tailed and a P < 0.05 was considered statistically significant.

RESULTS

Baseline characteristics comparison

After PSM, 65 patients were included in the CSGB group and 70 in the control group. No statistical differences existed between groups in baseline characteristics including age, gender, BMI, smoking history, comorbidities, tumor stage, surgical method, operative time, and intraoperative blood loss (P > 0.05), indicating good comparability. Mean age was 58.3 ± 8.7 years in the CSGB group and 59.1 ± 9.2 years in controls; male proportions were 56.9% and 58.6%; mean BMI was 23.8 ± 3.2 kg/m² and 24.1 ± 3.5 kg/m²; patients with stage I-II tumors comprised 81.5% and 78.6%, respectively (Table 1).

Table 1 Baseline characteristics comparison, n (%)/mean ± SD.

Variable	CSGB group (n = 65)	Control group (n = 70)	Statistics	P value
Age (year)	58.3 ± 8.7	59.1 ± 9.2	t = 0.521	0.603
Gender (male)	37 (56.9)	41 (58.6)	χ2 = 0.041	0.840
BMI (kg/m2)	23.8 ± 3.2	24.1 ± 3.5	t = 0.521	0.603
Smoking history (yes)	29 (44.6)	33 (47.1)	χ2 = 0.092	0.762
Comorbidities (yes)	25 (38.5)	28 (40.0)	χ2 = 0.035	0.851
Tumor stage (I-II)	53 (81.5)	55 (78.6)	χ2 = 0.180	0.671
Surgical method (lobectomy)	50 (76.9)	54 (77.1)	χ2 = 0.002	0.964
Operative time (minute)	142.5 ± 28.3	145.2 ± 30.1	t = 0.541	0.590
Intraoperative blood loss (mL)	92.4 ± 21.7	95.3 ± 23.5	t = 0.741	0.460

CSGB: Continuous stellate ganglion block; BMI: Body mass index.

Emotional score changes

Preoperative SAS and SDS scores were within normal range for both groups, with no statistical differences (P > 0.05). On postoperative day 1, both groups showed markedly elevated SAS and SDS scores compared to preoperative levels, but no between-group differences. On postoperative day 3, the CSGB group’s SAS score was 42.8 ± 6.3, significantly lower than the control group’s 49.2 ± 7.1 (P < 0.01); SDS scores were 41.5 ± 5.9 and 48.7 ± 6.8, respectively, also showing statistical significance (P < 0.01). On postoperative day 7, CSGB group SAS and SDS scores further decreased to 38.2 ± 5.4 and 37.1 ± 5.2, while controls scored 45.3 ± 6.5 and 44.8 ± 6.1, with persistent between-group differences (P < 0.01). Repeated measures analysis of variance showed significant time-by-group interaction (P < 0.01), suggesting superior anxiety and depression improvement trends in the CSGB group (Table 2).

Table 2 Emotional score changes, mean ± SD.

Scale	Time point	CSGB group (n = 65)	Control group (n = 70)	Statistics	P value
SAS	Preoperative	38.4 ± 5.2	38.9 ± 5.5	t = 0.541	0.590
	Postoperative day 1	46.1 ± 6.0	47.3 ± 6.4	t = 1.130	0.261
	Postoperative day 3	42.8 ± 6.3	49.2 ± 7.1	t = 5.620	< 0.01
	Postoperative day 7	38.2 ± 5.4	45.3 ± 6.5	t = 6.930	< 0.01
SDS	Preoperative	37.8 ± 4.9	38.2 ± 5.1	t = 0.471	0.639
	Postoperative day 1	45.3 ± 5.7	46.5 ± 6.0	t = 1.210	0.229
	Postoperative day 3	41.5 ± 5.9	48.7 ± 6.8	t = 6.480	< 0.01
	Postoperative day 7	37.1 ± 5.2	44.8 ± 6.1	t = 7.840	< 0.01

CSGB: Continuous stellate ganglion block; SAS: Self-Rating Anxiety Scale; SDS: Self-Rating Depression Scale.

Pain control efficacy

The CSGB group demonstrated clear advantages in postoperative pain control. On postoperative day 1, CSGB group resting VAS score was 3.2 ± 0.8, significantly lower than the control group’s 4.1 ± 0.9 (P < 0.05); movement VAS scores were 4.3 ± 1.0 and 5.4 ± 1.2, respectively, also showing statistical significance (P < 0.05). On postoperative day 3, CSGB group resting and movement VAS scores decreased to 2.1 ± 0.6 and 3.0 ± 0.7, while controls remained at 3.2 ± 0.8 and 4.2 ± 0.9 (P < 0.05). On postoperative day 7, CSGB group VAS scores continued at lower levels, with resting and movement states at 1.3 ± 0.4 and 2.1 ± 0.5, compared to controls at 2.3 ± 0.6 and 3.4 ± 0.8 (P < 0.05, Table 3).

Table 3 Comparison of Visual Analog Scale scores at different postoperative time points, mean ± SD.

State	Time point	CSGB group (n = 65)	Control group (n = 70)	Statistics	P value
Resting VAS	Postoperative day 1	3.2 ± 0.8	4.1 ± 0.9	t = 6.12	< 0.05
	Postoperative day 3	2.1 ± 0.6	3.2 ± 0.8	t = 8.93	< 0.05
	Postoperative day 7	1.3 ± 0.4	2.3 ± 0.6	t = 11.34	< 0.05
Movement VAS	Postoperative day 1	4.3 ± 1.0	5.4 ± 1.2	t = 5.71	< 0.05
	Postoperative day 3	3.0 ± 0.7	4.2 ± 0.9	t = 8.54	< 0.05
	Postoperative day 7	2.1 ± 0.5	3.4 ± 0.8	t = 11.07	< 0.05

CSGB: Continuous stellate ganglion block; VAS: Visual Analog Scale.

Sleep quality improvement

Preoperative PSQI scores showed no statistical differences between groups (P > 0.05), with mean scores around 5, indicating acceptable preoperative sleep quality. On postoperative day 7, the CSGB group PSQI score was 6.8 ± 1.5, which was significantly lower than the control group’s 9.2 ± 1.8 (P < 0.05). Further analysis of PSQI dimensions revealed significant improvements in the CSGB group for subjective sleep quality, sleep latency, sleep efficiency, sleep disturbances, and daytime dysfunction (P < 0.05). Notably, the proportion of patients with “poor” sleep quality (PSQI ≥ 7) on postoperative day 7 was 32.3% in the CSGB group, significantly lower than 61.4% in controls (P < 0.01, Table 4).

Table 4 Sleep quality improvement, mean ± SD.

Indicator	Time point	CSGB group (n = 65)	Control group (n = 70)	Statistics	P value
PSQI total score	Preoperative	5.1 ± 1.2	5.0 ± 1.3	t = 0.46	0.646
	Postoperative day 7	6.8 ± 1.5	9.2 ± 1.8	t = 8.52	< 0.05
Subjective sleep quality	Postoperative day 7	1.1 ± 0.3	1.6 ± 0.4	t = 8.06	< 0.05
Sleep latency	Postoperative day 7	1.0 ± 0.2	1.5 ± 0.4	t = 8.96	< 0.05
Sleep efficiency	Postoperative day 7	0.9 ± 0.2	1.4 ± 0.3	t = 10.81	< 0.05
Sleep disturbances	Postoperative day 7	1.2 ± 0.3	1.7 ± 0.4	t = 7.96	< 0.05
Daytime dysfunction	Postoperative day 7	1.1 ± 0.3	1.6 ± 0.4	t = 8.06	< 0.05
PSQI ≥ 7, n (%)	Postoperative day 7	21 (32.3)	43 (61.4)	χ2 = 11.22	< 0.01

CSGB: Continuous stellate ganglion block; PSQI: Pittsburgh Sleep Quality Index.

Accelerated recovery progress

Early postoperative recovery indicators were markedly superior in the CSGB group compared to controls. Time to first ambulation was 18.5 ± 4.2 hours in the CSGB group, significantly shorter than 26.3 ± 5.1 hours in controls (P < 0.05). For chest tube removal time, the CSGB group averaged 3.2 ± 0.8 days vs 4.1 ± 0.9 days in controls (P < 0.05). Hospital stay was 6.8 ± 1.3 days in the CSGB group and 8.5 ± 1.6 days in controls, with statistical significance (P < 0.05). Additionally, CSGB group patients’ independent walking distance on postoperative day 3 was 82.5 ± 15.3 m, which was significantly longer than controls’ 63.2 ± 12.7 m (P < 0.05), suggesting that CSGB may promote early mobilization by improving pain and emotional states. Compared to controls, CSGB group patients not only had shorter times to first ambulation, tube removal, and hospital discharge, but also faster gastrointestinal function recovery (flatus and defecation), approximately 30% increased walking distance on postoperative day 3, 8.4 points higher activities of daily living scores, and significantly higher serum albumin levels, indicating that CSGB comprehensively accelerated postoperative recovery by reducing stress and promoting early mobilization(Table 5).

Table 5 Accelerated recovery progress, mean ± SD.

Indicator	CSGB group (n = 65)	Control group (n = 70)	Statistics	P value
Time to first ambulation (hour)	18.5 ± 4.2	26.3 ± 5.1	t = 9.51	< 0.05
Chest tube removal time (day)	3.2 ± 0.8	4.1 ± 0.9	t = 6.07	< 0.05
Postoperative hospital stay (day)	6.8 ± 1.3	8.5 ± 1.6	t = 6.71	< 0.05
Postoperative day 3 walking distance (m)	82.5 ± 15.3	63.2 ± 12.7	t = 7.92	< 0.05
Time to first flatus (hour)	28.4 ± 5.6	34.7 ± 6.2	t = 6.27	< 0.05
Time to first defecation (hour)	48.3 ± 8.1	56.9 ± 9.4	t = 5.67	< 0.05
Postoperative day 3 ADL score (Barthel Index)	85.2 ± 8.7	76.8 ± 10.3	t = 5.21	< 0.05
Postoperative day 3 serum albumin (g/L)	38.6 ± 3.4	35.9 ± 3.8	t = 4.41	< 0.05

CSGB: Continuous stellate ganglion block; ADL: Activities of daily living.

Reduced complications

Postoperative complication rates were significantly lower in the CSGB group compared to controls. CSGB group postoperative nausea and vomiting incidence was 13.8%, markedly lower than controls’ 28.6% (P < 0.05). For arrhythmias, CSGB group incidence was 4.6% vs controls’ 12.9% (P < 0.05). Pulmonary infection rates were 6.2% in CSGB group and 15.7% in controls (P < 0.05). Other complications such as subcutaneous emphysema and atelectasis showed no statistical differences between groups (P > 0.05). Total complication rate was 24.6% in CSGB group, significantly lower than controls’ 42.9% (P < 0.05). Further analysis found that complication reduction may relate to CSGB’s improvements in patient pain, early mobilization promotion, and stress response reduction (Table 6).

Table 6 Reduced complications, n (%).

Complication	CSGB group (n = 65)	Control group (n = 70)	χ2 value	P value
Nausea and vomiting	9 (13.8)	20 (28.6)	4.57	< 0.05
Arrhythmias	3 (4.6)	9 (12.9)	3.89	< 0.05
Pulmonary infection	4 (6.2)	11 (15.7)	4.23	< 0.05
Subcutaneous emphysema	5 (7.7)	7 (10.0)	0.29	0.592
Atelectasis	2 (3.1)	4 (5.7)	0.64	0.424
Pleural effusion	3 (4.6)	8 (11.4)	3.32	< 0.05
Incisional infection	1 (1.5)	6 (8.6)	3.91	< 0.05
Deep vein thrombosis	0 (0.0)	4 (5.7)	4.21	< 0.05
Urinary retention	2 (3.1)	7 (10.0)	3.12	< 0.05
Total complications	16 (24.6)	30 (42.9)	5.60	< 0.05

CSGB: Continuous stellate ganglion block.

Logistic regression results

Logistic regression showed that after controlling for confounding factors such as age, gender, tumor stage, and operative time, each 1-point increase in resting VAS score on postoperative day 3 increased the risk of anxiety (SAS ≥ 50) by 72% [odds ratio (OR) = 1.72, 95% confidence interval (CI): 1.37-2.16, P < 0.01]; each 1-point increase in movement VAS score increased anxiety risk by 62% (OR = 1.62, 95%CI: 1.31-2.01, P < 0.01). Additionally, female patients had approximately twice the anxiety risk of males (OR = 2.05, 95%CI: 1.17-3.59, P = 0.013). When resting VAS ≥ 4 points, anxiety risk increased significantly by 2.34-fold (OR = 2.34, 95%CI: 1.25-4.38, P < 0.05), suggesting postoperative pain is an independent and modifiable risk factor for anxiety (Figure 1).

Figure 1 Forest plot of risk factors for postoperative anxiety (Self-Rating Anxiety Scale ≥ 50). Logistic regression analysis showing odds ratios (ORs) and 95% confidence intervals (CIs) for independent risk factors associated with postoperative anxiety in thoracoscopic lung cancer surgery patients. Blue bars represent point estimates of OR values, with horizontal lines indicating 95%CIs. The red dashed vertical line marks OR = 1 (no effect). All confidence intervals exclude 1, indicating statistical significance (P < 0.05). After adjusting for confounding variables including age, gender, tumor stage, and operative time, resting Visual Analog Scale (VAS) ≥ 4 points demonstrated the highest risk (OR = 2.34, 95%CI: 1.25-4.38), followed by female gender (OR = 2.05, 95%CI: 1.17-3.59). Each 1-point increase in resting VAS and movement VAS scores increased anxiety risk by 72% and 62%, respectively. These findings highlight postoperative pain as an independent and modifiable risk factor for anxiety development. OR: Odds ratios; VAS: Visual Analog Scale.

DISCUSSION

This is the first study to fully investigate CSGB in thoracoscopic lung cancer surgery through a “pain-emotion-recovery” framework. The results have shown clinically significant benefits in anxiety and depression outcomes with an acceptable number needed to treat estimates vs these traditional regional techniques as epidural analgesia or paravertebral block[16,17]. Such reductions in length of stay and complications would also represent major cost savings from a health economics perspective (not only avoiding secondary surgical interventions but also treatment of hospital-acquired emotional disorders[18]). These advantages justify multi-center validation, including cost-effectiveness data in specific payment models. While previous evidence suggests a link between early postoperative functional mobility and survival outcomes[19], as well as nutritional status related to recurrence risk, further confirmative study with long-term follow up is needed however this works suggest potential long term benefits in functional mobility, activities of daily living and nutritional markers.

CSGB likely exerts its effects through multiple connected pathways. At the neurochemical level, sustained sympathetic blockade might improve monoaminergic neurotransmission in areas of the brain regulating emotion, as animal models show prolonged elevations of serotonin and dopamine[20] and potentiation of inhibitory prefrontal-amygdala circuits[21]. At the level of the neuroendocrine system, disruption of sympathetic afferents inhibits HPA axis activity, leading to reductions in corticotropin-releasing hormone and normalization of diurnal cortisol dynamics[22], which may break a pathologic cycle wherein dysfunctional activation of the HPA axis is linked to an emotional disorder. On the level of immune-inflammatory, attenuation of inflammatory responses due to surgical trauma decreases pro-inflammatory cytokine production[23], which suppresses both microglial activation and central sensitization. Vagal afferents or blood-brain barrier transport of peripheral inflammatory mediators trigger central nervous system production of microglial inflammatory molecules that inhibit serotonergic transmission and mediate “inflammatory depression”[24]. Future work with functional neuroimaging, molecular imaging, and microbiome analysis can define a comprehensive mechanistic framework.

CSGB was shown to restore gastrointestinal function more effectively compared with epidural analgesia when integrated into enhanced recovery after surgery (ERAS) protocols[25], a mechanism likely due to prevention of opioid-mediated intestinal inhibition, the reduction of sympathetic suppression of the enteric nervous system, and diminished inflammatory interference. Enhanced early ambulation and functional independence have crossed clinically important thresholds[26], thereby establishing a beneficial “analgesia-activity-recovery” feedback loop that diminishes the rates of thromboembolism, infections, and muscle atrophy. Improved protein metabolism indicates modulation of stress response, decline in pro-inflammatory catabolism and facilitated intestinal absorption. The changes for functional complications with CSGB reflect the ERAS message of ‘comprehensive optimization with functional focus’, which promotes patients’ reported outcome and quality of life improvements beyond pain scores. Future studies should include CSGB in pillar ERAS frameworks that have designated and standardized protocols for facilitating pathway harmonization.

Key vulnerability factors were identified using logistic regression. An increased risk in female patients is attributed to estrogen-enhanced amygdala and pain pathways, maternal care paradigms, or sex-based variations in emotional regulation and coping skills[27]. Increased age, greater neuroticism measures[28] and pre-surgery chronic pain[29] are other risk factors. CSGB should be prioritized for those at high risk in combination with non-pharmacological interventions such as cognitive behavioral therapy, mindfulness-based stress reduction, and music therapy to provide “bio-psycho-social” comprehensive management. CSGB’s opioid-sparing effects make it especially beneficial in older patients, who are at greater risk of respiratory depression and other complications associated with opioids including cognitive dysfunction and delirium. Preoperative risk stratification models would allow for stepped intervention strategies ultimately allowing one to reach precision anesthetic management.

The lack of serious complications is a reflection of the standardized ultrasound-guided technique and appropriate dosing[30]. Key practise points included using ultrasound for preoperative anatomical assessment, in-plane needle visualisation, low volume with diluted drug infusion and confirming post-placement. The contraindications include the local infection, coagulopathy, local anesthetic hypersensitivity and severe cardiac conduction abnormality. Technical safety is ensured by operator competence and QA system. Special populations require protocol modifications. Further studies should optimize local anesthetic protocols and explore its combinations with other regional techniques.

Study limitations

This study has the following limitations: Single-center retrospective design may have unmeasured confounding despite PSM; plasma cortisol, interleukin-6 indicators not tested; lacks 6-month chronic pain and quality of life data; only single dose regimen used. Future plans include a 3-center, 260-patient randomized controlled trial detecting inflammatory and neurotransmitter indicators, tracking 12-month chronic postoperative pain and mental health status, with different dose gradients (0.15%, 0.2%, 0.25%) to explore minimum effective concentration and duration. Additionally, combining functional near-infrared spectroscopy to observe prefrontal oxygenation changes, directly verifying “sympathetic-prefrontal-limbic” pathways.

CONCLUSION

CSGB, by blocking sympathetic afferents, inhibiting HPA axis overactivation, and reducing inflammatory burden, significantly alleviates postoperative pain and anxiety/depression after thoracoscopic lung cancer surgery while accelerating gastrointestinal function recovery and improving early mobility, representing a safe and feasible “dual physical-psychological intervention” approach. With ultrasound popularization and ERAS philosophy promotion, CSGB is poised to upgrade from “analgesic supplement” to “standard emotional management component”, ultimately achieving thoracic surgery postoperative “pain-free, anxiety-free, rapid recovery” triple zero goals.