Effect of lidocaine on intraoperative blood pressure variability in patients undergoing major vascular surgery.

BACKGROUND: Dynamic fluctuations of arterial blood pressure known as blood pressure variability (BPV) may have short and long-term undesirable consequences. During surgical procedures blood pressure is usually measured in equal intervals allowing to assess its intraoperative variability, which significance for peri and post-operative period is still under debate. Lidocaine has positive cardiovascular effects, which may go beyond its antiarrhythmic activity. The aim of the study was to verify whether the use of intravenous lidocaine may affect intraoperative BPV in patients undergoing major vascular procedures. METHODS: We performed a post-hoc analysis of the data collected during the previous randomized clinical trial by Gajniak et al. In the original study patients undergoing elective abdominal aorta and/or iliac arteries open surgery were randomized into two groups to receive intravenous infusion of 1% lidocaine or placebo at the same infusion rate based on ideal body weight, in concomitance with general anesthesia. We analyzed systolic (SBP), diastolic (DBP) and mean arterial blood (MAP) pressure recorded in 5-minute intervals (from the first measurement before induction of general anaesthesia until the last after emergence from anaesthesia). Blood pressure variability was then calculated for SBP and MAP, and expressed as: standard deviation (SD), coefficient of variation (CV), average real variability (ARV) and coefficient of hemodynamic stability (C10%), and compared between both groups. RESULTS: All calculated indexes were comparable between groups. In the lidocaine and placebo groups systolic blood pressure SD, CV, AVR and C10% were 20.17 vs. 19.28, 16.40 vs. 15.64, 14.74 vs. 14.08 and 0.45 vs. 0.45 respectively. No differences were observed regarding type of surgery, operating and anaesthetic time, administration of vasoactive agents and intravenous fluids, including blood products. CONCLUSION: In high-risk vascular surgery performed under general anesthesia, lidocaine infusion had no effect on arterial blood pressure variability. TRIAL REGISTRATION: ClinicalTrials.gov; NCT04691726 post-hoc analysis; date of registration 31/12/2020.

Effects of intravenous single-bolus lidocaine infusion versus intravenous single-bolus magnesium sulfate infusion on postoperative pain, emotional status, and quality of life in patients undergoing spine fusion surgery: a randomized study.

BACKGROUND: We assessed the efficiency of intravenous adjuvants in decreasing opioid intake and pain scores after spine fusion surgery. METHODS: This study included 120 patients aged 18-60 listed for spine fusion surgery under general anesthesia. Patients were randomly assigned to four groups: Group (Lidocaine): received IV lidocaine 4 mg/kg in 50 mL volume over 30 min. Group (Magnesium): received IV magnesium sulfate 30mg/kg in 50 mL volume over 30 min. Group (combined Lidocaine and Magnesium): received IV lidocaine 4 mg/kg in 50 mL volume over 30 min.+IV magnesium sulfate 30mg/kg in 50 mL volume over 30 min. Group (Control): received IV saline 50 mL. The time to the first request analgesia, the postoperative pain score, total analgesic use, patient satisfaction, anxiety, depression, mental state, quality of life, and side effects were measured. RESULTS: The combined group had more extended time for the first analgesic request and fewer rescue analgesia doses than the other groups. NRS scores at rest or movement were statistically significantly lower in the lidocaine group and the combined group compared to the control group (P1, P3<0.05) at almost all times. This combination reduces anxiety and depression and improves overall health up to three months after a single infusion. The combined group had higher patient satisfaction. CONCLUSIONS: A synergistic effect of a combination of lidocaine and magnesium sulfate on perioperative pain was found. It reduces analgesic consumption, depression, and anxiety and improves overall health up to three months after a single infusion dose.

Prevention of persistent pain with lidocaine infusions in breast cancer surgery (PLAN): study protocol for a multicenter randomized controlled trial.

BACKGROUND: Persistent pain is a common yet debilitating complication after breast cancer surgery. Given the pervasive effects of this pain disorder on the patient and healthcare system, post-mastectomy pain syndrome (PMPS) is becoming a larger population health problem, especially as the prognosis and survivorship of breast cancer increases. Interventions that prevent persistent pain after breast surgery are needed to improve the quality of life of breast cancer survivors. An intraoperative intravenous lidocaine infusion has emerged as a potential intervention to decrease the incidence of PMPS. We aim to determine the definitive effects of this intervention in patients undergoing breast cancer surgery. METHODS: PLAN will be a multicenter, parallel-group, blinded, 1:1 randomized, placebo-controlled trial of 1,602 patients undergoing breast cancer surgery. Adult patients scheduled for a lumpectomy or mastectomy will be randomized to receive an intravenous 2% lidocaine bolus of 1.5 mg/kg with induction of anesthesia, followed by a 2.0 mg/kg/h infusion until the end of surgery, or placebo solution (normal saline) at the same volume. The primary outcome will be the incidence of persistent pain at 3 months. Secondary outcomes include the incidence of pain and opioid consumption at 1 h, 1-3 days, and 12 months after surgery, as well as emotional, physical, and functional parameters, and cost-effectiveness. DISCUSSION: This trial aims to provide definitive evidence on an intervention that could potentially prevent persistent pain after breast cancer surgery. If this trial is successful, lidocaine infusion would be integrated as standard of care in breast cancer management. This inexpensive, widely available, and easily administered intervention has the potential to reduce pain and suffering in an already afflicted patient population, decrease the substantial costs of chronic pain management, potentially decrease opioid use, and improve the quality of life in patients. TRIAL REGISTRATION: This trial has been registered on clinicaltrials.gov (NCT04874038, Dr. James Khan. Date of registration: May 5, 2021).

Population Pharmacokinetics of Intravenous Lidocaine in Adults: A Systematic Review.

BACKGROUND: The establishment of optimal dosing regimens for intravenous (IV) lidocaine in the perioperative setting, aiming to balance effective pain relief with minimisation of potential side effects, is a topic of ongoing debate. This discussion stems from the significant variability in lidocaine's pharmacokinetic (PK) parameters and its relatively narrow safety margin. Population pharmacokinetic (popPK) modelling has emerged as a valuable tool for understanding the factors contributing to this observed variability in drug kinetics. OBJECTIVES: This systematic review compiles the existing knowledge on lidocaine's PK properties and published popPK models, with a focus on significant covariates. METHODS: A systematic search on Cochrane CENTRAL, Medline, and EMBASE was performed from inception to June 2023. Original clinical studies that administered IV lidocaine to adults and performed PK analyses using a nonlinear mixed effects modelling approach were included. The quality of the included studies was assessed by compliance with the Clinical Pharmacokinetics (ClinPK) statement checklist. RESULTS: Seven studies were included, which involved a diverse adult population, including both volunteers and patients with various comorbidities. Lidocaine PK was primarily characterised by a two- or three-compartment model. The volume of distribution at steady state ranged from 66 to 194 L, and the total clearance ranged from 22 to 49 L/h. Despite adjusting for significant covariates like heart failure status, alpha-1-acid glycoprotein, duration of lidocaine infusion, and body weight, each study revealed substantial variability in PK parameters. The potential impact of hepatic or renal function biomarkers on these PK parameters calls for further investigation. Incomplete reporting of key aspects of developed models may hinder the models' reliability and clinical application. CONCLUSION: The findings emphasise the importance of tailoring drug dosage to ensure the safe and effective use of intravenous lidocaine. Optimal design methodologies may be incorporated for a more efficient identification of important covariates. Utilising contemporary model evaluation methods like visual predictive checks and bootstrapping would enhance the robustness of popPK models and the reliability of their predictions. This comprehensive review advances our understanding of lidocaine's pharmacokinetics and lays the groundwork for further research in this critical area of perioperative pain management. Review protocol registered on 25 August 2023 in PROSPERO (CRD42023441113). This work was supported by the Fundamental Research Grant Scheme, the Ministry of Higher Education, Malaysia (FRGS/1/2020/SKK01/UM/02/2).

A systematic review of procedural modalities in the treatment of notalgia paresthetica.

BACKGROUND: Notalgia paresthetica (NP) is a rare condition characterized by localized pain and pruritus of the upper back, associated with a distinct area of hyperpigmentation. Given the lack of standardized treatment and the uncertain efficacy of available options, applying procedural methods is of growing interest in treating NP. AIMS: We sought to comprehensively evaluate the role of procedural treatments for NP. METHODS: We systematically searched PubMed/Medline, Ovid Embase, and Web of Science until November 14th, 2023. We also performed a citation search to detect all relevant studies. Original clinical studies published in the English language were included. RESULTS: Out of 243 articles, sixteen studies have reported various procedural modalities, with or without pharmacological components, in treating NP. Pharmacological procedures, including injections of botulinum toxin, lidocaine, and corticosteroids, led to a level of improvement in case reports and case series. However, botulinum toxin did not show acceptable results in a clinical trial. Moreover, non-pharmacological procedures were as follows: physical therapy, exercise therapy, kinesiotherapy, acupuncture and dry needling, electrical muscle stimulation, surgical decompression, and phototherapy. These treatments result in significant symptom control in refractory cases. Physical therapy can be considered a first-line choice or an alternative in refractory cases. CONCLUSION: Procedural modalities are critical in the multidisciplinary approach to NP, especially for patients who are refractory to topical and oral treatments. Procedural modalities include a spectrum of options that can be applied based on the disease's symptoms and severity.

Long-term pain outcomes after serial lidocaine infusion in participants with recent onset of peripheral neuropathic pain: A pilot double-blind, randomized, placebo-controlled trial.

BACKGROUND: This study investigated the outcomes up to 12 weeks after serial lidocaine infusion for early-onset peripheral neuropathic pain. METHODS: This pilot double-blind, randomized, 2-arm placebo-controlled trial recruited 50 participants with onset of peripheral neuropathic pain within the past 6 months and randomized them to either receive lidocaine (3 mg/kg) in normal saline (50 mL) intravenous infusion over 1 hour (lidocaine group) once a week for 4 weeks or 50 mL of normal saline infusion (placebo group) once a week for 4 weeks. Twenty-nine participants completed the protocol; 15 participants were assigned to the lidocaine group and 14 to the placebo group. The outcomes were pain intensity assessed using a numerical rating scale (NRS), quality of life assessed using EuroQol-Five Dimensions-Five Levels questionnaire (EQ-5D-5L), psychological function using the Thai version of the 21-item Depression Anxiety Stress Scales (DASS-21), pain medication use, and adverse effects, all assessed at baseline (BL) and again at 4, 8, and 12 weeks following randomization. RESULTS: The reported tramadol use at 8 and 12 weeks following the first infusion was significantly lower in the lidocaine group (P = .023). No other significant between-group differences were observed at any time point or for any other outcome, and no serious adverse events were observed. CONCLUSION: Multiple lidocaine infusions of 3 mg/kg once a week for 4 weeks in participants with recent onset of peripheral neuropathic pain demonstrated no significant benefits in pain intensity, quality of life, or psychological outcomes. At most, this treatment may result in less tramadol use.

Balanced opioid-free anesthesia with lidocaine and esketamine versus balanced anesthesia with sufentanil for gynecological endoscopic surgery: a randomized controlled trial.

In this randomized controlled trial, 74 patients scheduled for gynecological laparoscopic surgery (American Society of Anesthesiologists grade I/II) were enrolled and randomly divided into two study groups: (i) Group C (control), received sufentanil (0.3 µg/kg) and saline, followed by sufentanil (0.1 µg/kg∙h) and saline; and (ii) Group F (OFA), received esketamine (0.15 mg/kg) and lidocaine (2 mg/kg), followed by esketamine (0.1 mg/kg∙h) and lidocaine (1.5 mg/kg∙h). The primary outcome was the 48-h time-weighted average (TWA) of postoperative pain scores. Secondary outcomes included time to extubation, adverse effects, and postoperative sedation score, pain scores at different time points, analgesic consumption at 48 h, and gastrointestinal functional recovery. The 48-h TWAs of pain scores were 1.32 (0.78) (95% CI 1.06-1.58) and 1.09 (0.70) (95% CI 0.87-1.33) for Groups F and C, respectively. The estimated difference between Groups F and C was - 0.23 (95% CI - 0.58 - 0.12; P = 0.195). No differences were found in any of the secondary outcomes and no severe adverse effects were observed in either group. Balanced OFA with lidocaine and esketamine achieved similar effects to balanced anesthesia with sufentanil in patients undergoing elective gynecological laparoscopic surgery, without severe adverse effects.Clinical Trial Registration: ChiCTR2300067951, www.chictr.org.cn 01 February, 2023.

Lidocaine effects on neutrophil extracellular trapping and angiogenesis biomarkers in postoperative breast cancer patients with different anesthesia methods: a prospective, randomized trial.

BACKGROUND: Anesthesia techniques and drug selection may influence tumor recurrence and metastasis. Neutrophil extracellular trapping (NETosis), an immunological process, has been linked to an increased susceptibility to metastasis in individuals with tumors. Furthermore, recurrence may be associated with vascular endothelial growth factor A (VEGF-A), a mediator of angiogenesis. This study investigates the impact of lidocaine (combined with sevoflurane or propofol anesthesia ) during breast cancer surgery inhibits the expression of biomarkers associated with metastasis and recurrence (specifically H3Cit, NE, MPO, MMP-9 and VEGF-A). METHODS: We randomly assigned 120 women undergoing primary or invasive breast tumor resection to receive one of four anesthetics: sevoflurane (S), sevoflurane plus i.v. lidocaine (SL), propofol (P), and propofol plus i.v. lidocaine (PL). Blood samples were collected before induction and 3 h after the operation. Biomarkers associated with NETosis (citrullinated histone H3 [H3Cit], myeloperoxidase [MPO], and neutrophil elastase [NE]) and angiogenesis were quantified using enzyme-linked immunosorbent assays. RESULTS: Patient and breast tumor characteristics, along with perioperative management, did not differ between study groups. In intra-group comparisons, S and P groups demonstrated a statistically significant increase in post-operative MPO (S group: 10.39[6.89-17.22] vs. 14.31[8.55-20.87] ng ml-1, P = 0.032; P group: 9.45[6.73-17.37] vs. 14.34[9.87-19.75] ng ml-1, P = 0.035)and NE(S group: 182.70[85.66-285.85] vs. 226.20[91.85-391.65] ng ml-1, P = 0.045; P group: 154.22[97.31-325.30] vs. 308.66[132.36-483.57] ng ml-1, P = 0.037) concentrations compared to pre-operative measurements, whereas SL and PL groups did not display a similar increase. H3Cit, MMP-9, and VEGF-A concentrations were not significantly influenced by the anesthesia techniques and drugs. CONCLUSIONS: Regardless of the specific technique employed for general anesthesia, there was no increase in the postoperative serum concentrations of MPO and NE after perioperative lidocaine infusion compared to preoperative serum concentrations. This supports the hypothesis that intravenous lidocaine during cancer surgery aimed at achieving a cure may potentially decrease the likelihood of recurrence. Further interpretation and discussion of clinical implications are warranted, emphasizing the significance of these findings in the context of cancer surgery and recurrence prevention. CLINICAL TRIAL REGISTRATION: ChiCTR2300068563.

Nerve Block Guided by Anatomic Landmarks Only Reduces Pain in Botulinum Toxin Type A Treatment for Glabellar and Forehead Wrinkles.

BACKGROUND: Botulinum toxin type A is widely used to treat glabellar and forehead wrinkles, but the pain caused by multiple injections often deters patients from receiving long-term treatment. Despite several methods used to alleviate this pain, consistency and effectiveness remain a challenge. Therefore, this study aimed to evaluate the effectiveness and safety of nerve block guided by anatomic landmarks only in reducing pain associated with botulinum toxin type A injections. PATIENTS AND METHODS: Between 2018 and 2022, the study enrolled 90 patients divided into 3 groups: the nerve block group (n = 30), the lidocaine cream group (n = 30), and the control group (n = 30). In the nerve block group, a landmarks-based technique was used to perform the nerve block. The study collected general information and comorbidities, and recorded pain at each point and time spent on preparation and treatment for each patient's forehead and glabellar area on each side. Patient-reported outcomes and complications were followed up at 2, 4, and 12 weeks after the injections. RESULTS: The nerve block group had significantly lower total pain scores in all regions compared to the lidocaine cream and control groups (P < 0.01). There were no significant differences in patient-reported outcomes between the groups at any follow-up point. Additionally, the complication rates related to injection were low and comparable among the 3 groups. CONCLUSIONS: Nerve block guided by anatomic landmarks only is a safe, effective, and consistent approach to reduce pain during botulinum toxin type A treatment for glabellar and forehead lines. This technique may offer advantages over other methods used to alleviate the pain associated with these injections.

Efficacy of Lidocaine Spray for Pain Reduction during Colposcopy-Directed Cervical Biopsies: A Randomized Controlled Trial.

Objectives: The objective of this study was to evaluate the efficacy of lidocaine spray in reducing the pain during colposcopy-directed cervical biopsy (CDB). Methods: From December 2017 to February 2019, 312 women undergoing CDBs were enrolled. The participants were randomized to three groups: group 1 (lidocaine spray), in which lidocaine spray was applied thoroughly to the cervix; group 2 (placebo), in which normal saline was applied thoroughly to the cervix; and group 3 (control), in which no anesthetic agent was applied to the cervix. Each woman completed a 10 cm visual analog scale to classify the subjective pain experience at three time points: baseline, immediately after biopsy, and 10 min after the procedure. The primary outcome of this study was the biopsy pain score. Results: The 312 enrolled women were randomly assigned to the three groups, amounting to 104 women per group. The clinical and pathological characteristics of the participants in all groups were comparable. The baseline, the biopsy, and the post-procedure pain scores were comparable among the three groups. There was a significant increase in the pain score from baseline to biopsy and from baseline to post-procedure in each group. The pain-score changes from baseline to biopsy in the lidocaine spray group significantly decreased when compared with the normal saline group (<0.001), and tended to decrease, though not significantly (p = 0.06), when compared with the control group. No complication with the intervention was observed. Conclusions: The application of lidocaine spray to the cervix has the benefit of reducing the pain associated with CDBs by a small amount. However, the intervention is safe and may be considered in nulliparous and/or overly anxious women undergoing the procedure.

Influence of Pre- and Intraoperative Local Anaesthetic in Strabismus Surgery under General Anaesthesia in Adults.

BACKGROUND: As studies have shown a reduction in the occurrence of the oculocardiac reflex with the addition of local anaesthesia, we changed our care regime accordingly a few years ago. To promote and establish better patient care, we retrospectively analysed the files of our patients who underwent strabismus surgery from 2013 to 2021 in order to compare strabismus surgery under general anaesthesia with and without local anaesthetics in a routine clinical setting. PATIENTS AND METHODS: Data from 238 adult patients who had undergone strabismus surgery could be extracted from the files: G1: n = 102, only general anaesthesia; G2: n = 136, preoperative application of tetracaine eye drops and intraoperative subtenon lidocaine/levobupivacaine in addition to general anaesthesia. We compared the two groups in regard to the frequency of oculocardiac reflex, the amount of atropine needed to treat, as well as the amount of antiemetic and analgesic medication given, and time spent in the recovery room. RESULTS: Mean age of G1 was 50 years and 52 years in G2. There was no significant difference between the kind of surgeries (recessions/resections), the number of patients who had undergone a reoperation, or the duration of the operations. Adding local anaesthetics resulted in significantly less occurrence of oculocardiac reflex (p = 0.009), a reduction in the need for atropine, analgesic, or antiemetic medication, as well as reduced time in the recovery room. CONCLUSION: As this increases patient safety and comfort and is cost-effective (less time in the recovery room), we recommend adding perioperative local anaesthesia to strabismus surgery performed under general anaesthesia.

A comparative analysis of opioid-free and opioid-sparing anaesthesia techniques for laparoscopic ovariectomy in healthy dogs.

OBJECTIVE: To compare the perioperative analgesic effects of an opioid-free (OFA) and an opioid-sparing (OSA) anaesthetic protocol in dogs undergoing laparoscopic ovariectomy. STUDY DESIGN: Prospective, randomized, blinded, clinical trial. ANIMALS: A group of 28 client-owned dogs. METHODS: Dogs were allocated to one of two groups. The OFA group was administered intramuscular (IM) dexmedetomidine 5 µg kg-1 and ketamine 1 mg kg-1, followed by two intraoperative constant rate infusions (CRIs) of dexmedetomidine (3 µg kg-1 hour-1) and lidocaine (1 mg kg-1 loading dose, 2 mg kg-1 hour-1). The OSA group was administered IM dexmedetomidine 5 µg kg-1, ketamine 1 mg kg-1 and methadone 0.2 mg kg-1, followed by two intraoperative saline CRIs. In both groups, anaesthesia was induced with intravenous (IV) propofol 2 mg kg-1 and diazepam 0.2 mg kg-1 and maintained with isoflurane. Rescue dexmedetomidine (0.5 µg kg-1) was administered IV if there was a 20% increase in cardiovascular variables compared with pre-stimulation values. Ketorolac (0.5 mg kg-1) was administered IV when the surgery ended. Postoperative analgesia was evaluated using the Short Form-Glasgow Composite Measure Pain Scale and methadone (0.2 mg kg-1) was administered IM if the pain score was ≥ 6/24. Statistical analysis included mixed analysis of variance, Chi-square test and Mann-Whitney U test. RESULTS: There were no significant differences in the intraoperative monitored variables between groups. The OFA group showed a significantly lower intraoperative rescue analgesia requirement (p = 0.016) and lower postoperative pain scores at 3 (p =0.001) and 6 (p < 0.001) hours. No dogs were administered rescue methadone postoperatively. CONCLUSIONS AND CLINICAL RELEVANCE: Although both groups achieved acceptable postoperative pain scores with no need for further intervention, the analgesic efficacy of the OFA protocol was significantly superior to that of the OSA protocol presented and was associated with a lower intraoperative rescue analgesia requirement and early postoperative pain scores.

Comparison of labetalol and lidocaine in induction of controlled hypotension in tympanoplasty: a randomized clinical trial.

OBJECTIVES: This study aimed to compare the efficacy of labetalol and lidocaine in tympanoplasty surgery, specifically evaluating their impact on hemodynamic changes and perioperative outcomes. METHODS: A randomized controlled trial was conducted with 64 patients scheduled for tympanoplasty. Patients were randomly assigned to receive either 0.5-2 mg/min labetalol or 1.5 mg/kg/h lidocaine 1% to achieve controlled hypotension during surgery. The efficacy of the drugs was assessed by comparing the Mean Arterial Pressure (MAP), surgeon's satisfaction, time to target MAP, bleeding volume, postoperative pain scores, the need for analgesic medication in recovery, sedation, and other additional parameters. RESULTS: The hemodynamic parameters showed a similar trend over time in both the labetalol and lidocaine groups. The median bleeding volume in the labetalol group (10 cc) was lower than that in the lidocaine group (30 cc), although this difference was not statistically significant (p = 0.11). Similarly, surgeon's satisfaction level, pain intensity, and sedation level in the recovery room did not show statistically significant differences between the two groups (p > 0.05). The duration of surgery, recovery stay, and extubation time also did not significantly differ between the groups. Both medications took approximately the same time (20 min) to reach the target MAP and exhibited comparable hemodynamic responses (p > 0.05). CONCLUSION: Both labetalol and lidocaine effectively achieved controlled hypotension during tympanoplasty surgery, thereby improving surgical conditions. The choice of medication should be based on individual patient characteristics and the anesthesiologist's judgment. LEVEL OF EVIDENCE: II.

Efficacy and safety of epidural block with lidocaine for refractory severe plaque psoriasis: An open-label pilot study in real world setting.

Epidural block using lidocaine, a non-selective blocker of voltage-gated sodium channels (Nav), has demonstrated efficacy in the treatment of severe plaque psoriasis in a limited number of cases. This study aimed to evaluate the effectiveness and safety of epidural lidocaine block in adult patients with severe, treatment-resistant plaque psoriasis. This was an open-label pilot study. Patients with severe plaque-type psoriasis unresponsive to at least one systemic treatment were enrolled for a 1-week epidural lidocaine block and followed up for 48 weeks. Thirty-six patients participated, with 32 completing the study. At the 12-week mark, there was a remarkable 59% improvement in the mean Psoriasis Area Severity Index (PASI) score (P < 0.001). By week 48, 28 out of 32 patients (87%) achieved PASI 75, while 18 out of 32 (56%) reached PASI 90. Within 7 days, 20 out of 21 patients (95%) reported a reduction in itch, with a mean itch reduction of 82% at day 1 and 94% at day 7. Notably, no severe side effects were observed. Epidural lidocaine block proved to be an effective and safe long-term treatment option for individuals with refractory severe plaque psoriasis.

Optimisation of reduction for prolapsed silicone tube after lacrimal intubation.

BACKGROUND: A common complication of bicanalicular intubation is dislocation of the silicone tube. METHODS: Eleven patients with prolapsed silicone tubes who had undergone bicanalicular nasal intubation were injected with a 2 per cent lidocaine solution to infiltrate the lacrimal duct mucosa. A memory wire probe was used to pull a 4-0 suture through the lacrimal passage retrogradely, allowing the suture to grab the silicone tube. Paraffin oil was applied to the contact part of the rope and the silicone tube, then the distal end of the silk thread was removed from the nostril until the tube was pulled into place. RESULTS: The prolapsed silicone tubes were restored by surgery in nine patients, with the drainage tube in the correct position in the eye and the lacrimal duct irrigation unobstructed. CONCLUSION: The optimisations made in this study are considered effective adjustments of reduction surgery for a prolapsed silicone tube.