Effects of perioperative magnesium on postoperative analgesia following thoracic surgery: a meta-analysis of randomised controlled trials.

To evaluate the analgesic effects of intravenous magnesium in patients undergoing thoracic surgery. Randomised clinical trials (RCTs) were systematically identified from MEDLINE, EMBASE, Google Scholar and the Cochrane Library from inception to May 1st, 2023. The primary outcome was the effect of intravenous magnesium on the severity of postoperative pain at 24 hours following surgery, while the secondary outcomes included association between intravenous magnesium and pain severity at other time points, morphine consumption, and haemodynamic changes. Meta-analysis of seven RCTs published between 2007 and 2019, involving 549 adults, showed no correlation between magnesium and pain scores at 1-4 (standardized mean difference [SMD]=-0.06; p=0.58), 8-12 (SMD=-0.09; p=0.58), 24 (SMD=-0.16; p=0.42), and 48 (SMD=-0.27; p=0.09) hours post-surgery. Perioperative magnesium resulted in lower equivalent morphine consumption at 24 hours post-surgery (mean difference [MD]=-25.22 mg; p=0.04) and no effect at 48 hours (MD=-4.46 mg; p=0.19). Magnesium decreased heart rate (MD = -5.31 beats/min; p=0.0002) after tracheal intubation or after surgery, but had no effect on postoperative blood pressure (MD=-6.25 mmHg; p=0.11). There was a significantly higher concentration of magnesium in the magnesium group compared with that in the placebo group (MD = 0.91 mg/dL; p<0.00001). This meta-analysis provides evidence supporting perioperative magnesium as an analgesic adjuvant at 24 hours following thoracic surgery, but no opioid-sparing effect at 48 hours post-surgery. The severity of postoperative pain did not significantly differ between any of the postoperative time points, irrespective of magnesium. Further research on perioperative magnesium in various surgical settings is needed.

The impact of perioperative ketamine or esketamine on the subjective quality of recovery after surgery: a meta-analysis of randomised controlled trials.

BACKGROUND: This meta-analysis aimed to evaluate the impact of ketamine/esketamine on postoperative subjective quality of recovery (QoR). METHODS: MEDLINE, Embase, Cochrane library, and Google Scholar were searched for randomised controlled trials (RCTs) that examined the impacts of perioperative ketamine/esketamine use and postoperative QoR. The primary outcome was subjective QoR (QoR-9, QoR-15, QoR-40) on postoperative day (POD) 1-3, whereas the secondary outcomes included pain severity, anxiety scores, depression scores, risk of adverse events (i.e. nausea, vomiting, dizziness, drowsiness), and length of stay. RESULTS: The analysis included 18 RCTs (1554 participants; ketamine: seven trials, esketamine: 11 trials), of which 15 were conducted in China. Ketamine/esketamine improved the QoR scores on PODs 1 and 2 compared with the control (standardised mean difference [SMD]: 0.63, P<0.0001 for POD 1; SMD: 0.56, P=0.04 for POD 2), without beneficial effect on POD 3. Subgroup analyses revealed significant differences in QoR scores on POD 1 by regimen (SMD: esketamine 1.14, ketamine 0.01) and country (SMD: China 0.82, other countries -0.21). The emotional domain of QoR was improved from PODs 1 to 3, whereas the other domains were only improved on POD 1. Lower postoperative anxiety (SMD: -0.48, P=0.003) and depression (SMD: -0.72, P=0.001) scores were also observed with ketamine/esketamine use. Furthermore, pain severity was reduced on PODs 1 and 2, with no difference in the risk of adverse events or length of stay. CONCLUSIONS: This meta-analysis demonstrated that ketamine/esketamine use in the perioperative period is associated with improved early subjective QoR, pain severity, and psychological symptoms without an increase in the likelihood of adverse events. SYSTEMATIC REVIEW PROTOCOL: PROSPERO (CRD42023477580).

Lidocaine induces epithelial­mesenchymal transition and aggravates cancer behaviors in non­small cell lung cancer A549 cells.

The effects of clinically relevant concentrations of lidocaine on epithelial-mesenchymal transition (EMT) and associated lung cancer behaviors have rarely been investigated. The aim of the present study was to assess the impact of lidocaine on EMT and its related phenomena, including chemoresistance. Lung cancer cell lines (A549 and LLC.LG) were incubated with various concentrations of lidocaine, 5-fluorouracil (5-FU) or both to test their effects on cell viability. Subsequently, the effects of lidocaine on various cell behaviors were assessed in vitro and in vivo using Transwell migration, colony-formation and anoikis-resistant cell aggregation assays, and human tumor cell metastasis in a chorioallantoic membrane (CAM) model quantitated by PCR analysis. Prototypical EMT markers and their molecular switch were analyzed using western blotting. In addition, a conditioned metastasis pathway was generated through Ingenuity Pathway Analysis. Based on these measured proteins (slug, vimentin and E-cadherin), the molecules involved and the alteration of genes associated with metastasis were predicted. Of note, clinically relevant concentrations of lidocaine did not affect lung cancer cell viability or alter the effects of 5-FU on cell survival; however, at this dose range, lidocaine attenuated the 5-FU-induced inhibitory effect on cell migration and promoted EMT. The expression levels of vimentin and Slug were upregulated, whereas the expression of E-cadherin was downregulated. EMT-associated anoikis resistance was also induced by lidocaine administration. In addition, portions of the lower CAM with a dense distribution of blood vessels exhibited markedly increased Alu expression 24 h following the inoculation of lidocaine-treated A549 cells on the upper CAM. Thus, at clinically relevant concentrations, lidocaine has the potential to aggravate cancer behaviors in non-small cell lung cancer cells. The phenomena accompanying lidocaine-aggravated migration and metastasis included altered prototypical EMT markers, anoikis-resistant cell aggregation and attenuation of the 5-FU-induced inhibitory effect on cell migration.

Usefulness of Analgesia Nociception Index for guiding intraoperative opioid administration: a systematic review and meta-analysis.

INTRODUCTION: This study primarily aimed at investigating the efficacy of Analgesia Nociception Index (ANI) for guiding intraoperative opioid administration in patients receiving surgery under general anesthesia. EVIDENCE ACQUISITION: The Medline, Embase, Google scholar, and the Cochrane Library databases were searched from inception to April 2022 for randomized controlled trials. The primary outcome was intraoperative opioid administration, while the secondary outcomes included postoperative opioid consumption, pain score, emergency time, risk of nausea/vomiting (PONV), and Postanesthesia Care Unit (PACU) stay. EVIDENCE SYNTHESIS: Six studies including 399 participants (published from 2015 to 2022) focused on non-cardiac surgery, including spine surgery (two trials), breast surgery (two trials), gynecologic surgery (one trial), and laparoscopic cholecystectomy (one trial) were included. Meta-analysis revealed no difference in intraoperative opioid administration with the use of ANI-guided analgesia compared to the control group that used conventional clinical measurements (e.g., heart rate) to guide opioid use [standardized mean difference (SMD)=-0.17, 95% CI: -0.56 to 0.22, P=0.39, I2=72%, six trials, 399 participants]. Gender-based subgroup analysis showed effectiveness of ANI for reducing opioid administration in female patients (SMD=-0.53, P=0.02). There were no differences in postoperative recovery characteristics including pain score [Mean difference (MD): -0.03, P=0.79], opioid consumption (SMD: -0.34, P=0.08), emergence time (MD=1.12, P=0.47), length of stay in the PACU (MD: -0.56, P=0.83), and risk of PONV [risk ratio(RR): 0.75, P=0.46] between the two groups. CONCLUSIONS: Analgesia nociception index-guided analgesia was unable to reduce intraoperative opioid administration compared to monitoring using conventional clinical parameters. Further studies are required to support our findings.

Impact of Opioid-Free Anesthesia on Analgesia and Recovery Following Bariatric Surgery: a Meta-Analysis of Randomized Controlled Studies.

This meta-analysis aimed at exploring the impact of opioid-free anesthesia (OFA) on pain score and opioid consumption in patients undergoing bariatric surgery (BS). Literature search identified eight eligible trials. Forest plot revealed a significantly lower pain score (mean difference (MD) = - 0.96, p = 0.0002; 318 patients), but not morphine consumption (MD = - 5.85 mg, p = 0.1; 318 patients) at postoperative 24 h in patients with OFA than in those without. Pooled analysis also showed a lower pain score (p = 0.002), morphine consumption (p = 0.0003) in the postanesthetic care unit, and risk of postoperative nausea/vomiting (p = 0.0003) in the OFA group compared to the controls. In conclusion, this meta-analysis demonstrated that opioid-free anesthesia improved pain outcomes immediately and at 24 h after surgery without a beneficial impact on opioid consumption at postoperative 24 h. KEY POINTS: • Roles of opioid-free anesthesia (OFA) in bariatric surgery (BS) were investigated. • Outcomes included postoperative pain score, opioid use, and nausea/vomiting risk. • OFA was associated with lower 24-h pain score but not opioid consumption. • Lower pain score and opioid consumption were noted in the postanesthetic care unit. • OFA correlated with a lower risk of postoperative nausea/vomiting.

Fire safety study on high-flow nasal oxygen in shared-airway surgeries with diathermy and laser: simulation based on a physical model.

High-flow nasal oxygen (HFNO) has been used in "tubeless" shared-airway surgeries but whether HFNO increased the fire hazard is yet to be examined. We used a physical model for simulation to explore fire safety through a series of ignition trials. An HFNO device was attached to a 3D-printed nose with nostrils connected to a degutted raw chicken. The HFNO device was set at twenty combinations of different oxygen concentration and gas flow rate. An electrocautery and diode laser were applied separately to a fat cube in the cavity of the chicken. Ten 30 s trials of continuous energy source application were conducted. An additional trial of continuous energy application was conducted if no ignition was observed for all the ten trials. A total of eight short flashes were observed in one hundred electrocautery tests; however, no continuous fire was observed among them. There were thirty-six events of ignition in one hundred trials with laser, twelve of which turned into violent self-sustained fires. The factors found to be related to a significantly increased chance of ignition included laser application, lower gas flow, and higher FiO2. The native tissue and smoke can ignite and turn into violent self-sustained fires under HFNO and continuous laser strikes, even in the absence of combustible materials. The results suggest that airway surgeries must be performed safely with HFNO if only a short intermittent laser is used in low FiO2.

Comparison of video-stylet and video-laryngoscope for endotracheal intubation in adults with cervical neck immobilisation: A meta-analysis of randomised controlled trials.

BACKGROUND: The efficacy of video-stylet versus video-laryngoscope for tracheal intubation in patients with cervical spine immobilisation, which is known to impede the intubation process, remains unclear. METHODS: We searched electronic databases including EMBASE, MEDLINE, Google Scholar, and Cochrane Library for randomised controlled trials comparing video-stylets with video-laryngoscopes in human subjects with cervical spine immobilisation from inception to the 25th of January 2021. The primary outcome was the rate of successful first-attempt intubation, while secondary outcomes included overall intubation success rate, time for successful intubation, and risk of tissue damage. RESULTS: Five trials (709 patients) published between 2009 and 2020 met the inclusion criteria. There were four types of video-stylets and three types of video-laryngoscopes examined. Hard cervical collar was applied in four studies, while manual inline stabilisation was used in one study for cervical immobilisation. There was no difference in successful first-attempt intubation rate between the video-stylet and the video-laryngoscope groups [risk ratio (RR) = 0.96, 95% CI: 0.90-1.03, p = 0.3; I2 = 47%] (5 trials, 709 patients). The overall success rate (RR = 0.98, 95% CI: 0.96-1.0, p = 0.05; I2 = 0%), intubation time [mean difference (MD) = 5.24, 95% CI: -8.95 to 19.43, p = 0.47; I2 = 92%], and risk of tissue damage (RR = 0.87, 95% CI: 0.26-2.85, p = 0.81; I2 = 39%) were also comparable between the two groups. CONCLUSIONS: This study validates the efficacy of both video-stylets and video-laryngoscopes for tracheal intubation in the situation of cervical spine immobilisation. Further large-scale trials are warranted to support our findings in this clinical setting.

Myasthenic crisis and late deep vein thrombosis following thymectomy in a patient with myasthenia gravis: A case report.

INTRODUCTION: Surgical stress and pain are potential provoking factors for postoperative myasthenic crisis (POMC). We report the occurrence of early POMC and late deep vein thrombosis (DVT) in a man with myasthenia gravis (MG) undergoing thymectomy, addressing possible link between reversal of opioid overdose with naloxone and the triggering of POMC. PATIENT CONCERNS: A 71-year-old man with impaired renal function (ie, estimated glomerular filtration rate [egfr]: 49.1 mL/min/1.73 m) with diagnosis of MG made 2 months ago was scheduled for thymectomy. After uncomplicated surgery, he experienced opioid overdose that was treated with naloxone. Hyperlactatemia then developed with a concomitant episode of hypertension. Three hours after reversal, he suffered from myasthenic crisis presenting with respiratory failure and difficult weaning from mechanical ventilation. DIAGNOSIS: Stress-induced hyperlactatemia and subsequent myasthenic crisis INTERVENTIONS:: Pyridostigmine and immunosuppressive therapy with prednisolone were initiated. Hyperlactatemia subsided on postoperative day (POD) 5. Tracheal extubation was performed successfully on POD 6. OUTCOMES: During the course of hospitalization, his eGFR (ie, 88.9 mL/min/1.73 m) was found to improve postoperatively. After discharge from hospital, he developed DVT in the left femoral and popliteal veins on POD 24 when he was readmitted for immediate treatment with low-molecular-weight heparin. He was discharged without sequelae on POD 31. There was no recurrence of myasthenic crisis or DVT at 3-month follow-up. CONCLUSIONS: Following naloxone administration, hyperlactatemia may be an indicator of pain-related stress response, which is a potential provoking factor for myasthenic crisis. Additionally, patients with MG may have an increased risk of DVT possibly attributable to immune-mediated inflammation. These findings highlight the importance of perioperative avoidance of provoking factors including monitoring of stress-induced elevations in serum lactate concentration, close postoperative surveying for myasthenic crisis, and early recognition of possible thromboembolic complications in this patient population.

Intravenous loading of nitroglycerin during rewarming of cardiopulmonary bypass improves metabolic homeostasis in cardiac surgery: a retrospective analysis.

PURPOSE: The aim of the study was to evaluate the effects of high-dose nitroglycerine (NTG) on glucose metabolism, tissue oxygenation and postoperative recovery in cardiac surgical patients. METHODS: Cardiac surgical patients in the retrospective survey were classified into two groups based on the NTG regimen. NTG group had intravenous loading of NTG (infusion rate 10-20 mg/h with total dose of ≥0.5 mg/kg) starting at rewarming of cardiopulmonary bypass (CPB) (n = 101), and control group had no intravenous loading of NTG (n = 151). Data for intraoperative plasma glucose and lactate levels, and regular insulin consumption were collected. Propensity score methodology was utilized to adjust for potential confounders. RESULTS: After adjustment for propensity score, the plasma glucose was significantly lower in the NTG group during (161 ± 39 versus 179 ± 45 mg/dl, p = 0.005) and after CPB (167 ± 41 versus 184 ± 48 mg/dl, p = 0.012). Total consumption of regular insulin was significantly lower in the NTG group, median 8 (range 0-50) versus 13 (0-90) international units, p = 0.005. There was a trend towards statistical significance in a lower incidence of hyperlactatemia (>2.2 mmol/l) in the NTG group during CPB, 21/100 (21 %) versus 40/132 (30.3 %), p = 0.065. The mixed venous oxygen saturation in the intensive care unit was higher in the NTG group, 65 ± 9 versus 62 ± 11 %, p = 0.056. CONCLUSIONS: Intravenous loading of NTG during and after CPB is safe and effective for attenuating the hyperglycemic response and reduce the incidence of hyperlactatemia during cardiac surgery with CPB.

Successful removal of a potentially lethal left atrial thrombus detected by transesophageal echocardiography following the removal of a left ventricular assist device inflow cannula.

The left ventricular assist device (LVAD) is a battery-operated, mechanical pump-type device that helps in maintaining the pumping ability of a failing heart. Thromboembolism poses a significant risk during and after LVAD implantation. It occurs in up to 35% of patients with adverse sequelae. We present the case of a 75-year-old man who underwent coronary artery bypass graft surgery and LVAD implantation for acute myocardial ischemia and severe left ventricular dysfunction. However, subsequent transthoracic echocardiographic examination revealed an LVAD thrombus, and LVAD removal was suggested following the failure of thrombolytic therapy. After the LVAD cannula was removed, transesophageal echocardiography (TEE) revealed a residual thrombus in the left atrium. Thrombectomy was successfully performed by opening the left atrium with cardiopulmonary bypass. We believe that TEE monitoring aided the implantation and removal of the LVAD device. In this case, we found that TEE not only helped in monitoring the ventricular function but also in detecting other problems such as the residual thrombus. We strongly recommend TEE monitoring during the entire LVAD-removal procedure, particularly for patients who need to undergo LVAD removal because of thrombosis formation.