Respiratory Tract (Lung and Bronchial) Diseases

Symptoms and General Pathology

All Conditions

Respiratory Aspiration

Respiration Disorders

Respiratory Tract Diseases

Adjuvants, Anesthesia

Analgesics

Central Nervous System Depressants

All Drugs and Chemicals

Psychotropic Drugs

Platelet Aggregation Inhibitors

Other Dietary Supplements

Sufentanil

Anesthetics

Fentanyl

Rocuronium

Midazolam

Propofol

Sevoflurane

Remifentanil

Benzocaine

Dsuvia

Hypnotics and Sedatives

Anesthetics, Intravenous

Anesthetics, General

Anesthetics, Inhalation

Tannic Acid

Anesthesia will be induced intravenously with midazolam (0.015-0.03 mg/kg), sufentanil, propofol, and rocuronium.

Sevoflurane will be administered by inhalation for anesthesia maintenance. The concentration of inhaled sevoflurane will be adjusted to maintain the bispectral index (BIS) value between 40 and 60. Analgesia will be supplemented with remifentanil (administered by continuous infusion), sufentanil (administered by intermittent injection/continuous infusion), or fentanyl (administered by intermittent injection).

Towards the end of surgery, sevoflurane inhalational concentration will be decreased and fentanyl/sufentanil will be administered when necessary. Sevoflurane inhalation will be stopped at the end of surgery.

Anesthesia will be induced intravenously with midazolam (0.015-0.03 mg/kg), sufentanil, propofol, and rocuronium.

Propofol will be administered by intravenous infusion for anesthesia maintenance. The infusion rate of propofol will be adjusted to maintain the BIS value between 40 and 60. Analgesia will be supplemented with remifentanil (administered by continuous infusion), sufentanil (administered by intermittent injection/continuous infusion), or fentanyl (administered by intermittent injection).

Towards the end of surgery, propofol infusion rate will be decreased and fentanyl/sufentanil will be administered when necessary. Propofol infusion will be stopped at the end of surgery.

Sevoflurane will be administered by inhalation for anesthesia maintenance. The concentration of inhaled sevoflurane will be adjusted to maintain the BIS value between 40 and 60. Sevoflurane inhalational concentration will be decreased towards the end of surgery. Sevoflurane inhalation will be stopped at the end of surgery.

Propofol will be administered by intravenous infusion for anesthesia maintenance. The infusion rate of propofol will be adjusted to maintain the BIS value between 40 and 60. Propofol infusion rate will be decreased towards the end of surgery. Propofol infusion will be stopped at the end of surgery.

Dong-Xin Wang, MD, PhD

Surgery is one of the major treatment methods for patients with malignant tumor. And, alone with the ageing process, more and more elderly patients undergo surgery for malignant tumor. Evidence emerges that choice of anesthetics, i.e., either inhalational or intravenous anesthetics, may influence the outcome of elderly patients undergoing cancer surgery. From the point of view of immune function after surgery and invasiveness of malignant tumor cells, propofol intravenous anesthesia may be superior to inhalational anesthesia. However, the clinical significance of these effects remains unclear. Retrospective studies indicated that use of propofol intravenous anesthesia was associated higher long-term survival rate. Prospective studies exploring the effect of anesthetic choice on long-term survival in cancer surgery patients are urgently needed.

It is estimated that 234.2 million major surgical procedures are undertaken every year worldwide. Surgery is one of the major treatment methods for patients with malignant tumor. And, alone with the ageing process, more and more elderly patients undergo surgery for malignant tumor. However, evidence emerges that choice of anesthetics, i.e., either inhalational or intravenous anesthetics, may influence the outcome of elderly patients undergoing cancer surgery.

A. Effects of anesthetics on immune function after surgery

The choice of general anesthetics might influence human's immune function after surgery. An international multicenter team (NCT00418457) investigated the effects of propofol-paravertebral anesthesia vs sevoflurane-opioid anesthesia on the immune function in patients after breast cancer surgery. In a small sample size (n = 32) randomized controlled trail published in 2010, postoperative serum concentrations of interleukin (IL)-1 (protumorigenic cytokine) and matrix metalloproteinases (MMP)-3/9 (associated with cancer cell invasion and metastasis) were significantly lower (P = 0.003 and 0.011, respectively), whereas that of IL-10 (antitumorigenic cytokines) was significantly higher in the propofol group than in the sevoflurane group (P = 0.001). In another small sample size (n = 10) randomized controlled trail published in 2014, serum obtained from patients who received propofol anesthesia led to greater human donor natural killer (NK) cell cytotoxicity in vitro when compared with serum from those who received sevoflurane anesthesia. In a recent small sample size (n = 28) randomized controlled trial, the levels of NK and T helper cell infiltration in breast cancer tissue were significantly higher in patients receiving propofol anesthesia than those receiving sevoflurane anesthesia (P = 0.015 and 0.03, respectively).

Similar findings were reported in patients with other malignant tumors. In a small randomized controlled trial, 30 patients with non-small-cell lung cancer randomly received either propofol or isoflurane anesthesia. The results showed that cluster of differentiation (CD)4+CD28+ percentage (P \< 0.0001) and the ratio of interferon-gamma:interleukin-4 (P = 0.001) all increased significantly with propofol but no change with isoflurane anesthesia; indicating that propofol promotes activation and differentiation of peripheral T-helper cells. In another randomized controlled trial, 60 patients undergoing surgery for tongue cancer surgery randomly received total propofol, mixed (propofol induction and sevoflurane maintenance) anesthesia or total sevoflurane anesthesia. The results showed that the percentages of CD3+, CD3+CD4+, and NK cells and the ratio of CD4+/CD8+ were significantly decreased in the two sevoflurane groups, but not in the total propofol group; suggesting that propofol has less effects on cellular immune response than sevoflurane. There are also studies that reported neutral results.

The above studies suggest that, when compared with inhalational anesthesia, propofol intravenous anesthesia may have favorable effects on the immune function in patients after cancer surgery. However, care must be taken when explaining these results: (1) the sample sizes of the available studies were small; (2) the relationship between postoperative immune function changes and long-term outcomes remains unclear.

B. Effects of anesthetics on invasiveness of malignant tumor

The effects of anesthetics on invasiveness of tumor cells were mainly tested in the experimental studies, i.e., tumor cells were incubated with anesthetics in the in vitro environment. In this aspect, propofol shows somewhat favorable effects. The results of Miao et al. showed that propofol stimulation decreased the expression of MMP-2 and -9 and subsequently decreased the invasive activity of human colon cancer cells, possibly via extracellular signal-regulated kinase 1/2 (ERK1/2) down-regulation mediated through the gamma-aminobutyric acid (GABA)-A receptor. The study of Wang et al. reported that propofol inhibited invasion and metastasis, and enhanced paclitaxel-induced apoptosis of ovarian cancer cells, possibly by suppressing the Slug expression. Ecimovic et al. also reported that propofol reduced migration in both estrogen receptor-positive and -negative breast cancer cells, possibly by suppressing the Neuroepithelial Cell Transforming Gene 1 (NET1) expression.

The reported effects of various inhalational anesthetics are conflicting. Huang et al. compared the effects of propofol and isoflurane on prostate cancer cells. The results showed that propofol, at clinical relevant concentration, inhibited the activation of hypoxia-inducible factor (HIF)-1 alpha, and partially reduced cancer cell malignant activities; whereas isoflurane raised HIF-1 alpha expression, and increased the probability of proliferation and migration. The study of Benaonana et al. reported similar results, i.e., isoflurane up-regulated the expression of HIFs, and increased the growth and malignant potential of renal cancer cells. On the other hand, sevoflurane and desflurane show opposite effects. Multiple studies found that sevoflurane inhibited the proliferation and migration, and induced apoptosis of lung cancer cells. Müller-Edenborn et al. also reported that volatile anesthetics (sevoflurane and desflurane) reduced invasion of colorectal cancer cells through down-regulation of matrix metalloproteinase-9.

So far, the clinical significance of anesthetics on the invasiveness of malignant tumors is still lacking.

C. Effect of anesthetics on long-term outcome after cancer surgery

Studies in this aspect are very limited. In the study of Enlund et al., 2838 patients who underwent breast cancer or colorectal cancer surgery were retrospectively analyzed, among them 1935 received sevoflurane anesthesia and 903 propofol anesthesia. The 1-year and 5-year survival rates were higher in propofol-anesthetized patients than in sevoflurane-anesthetized ones (differences in overall survival rate were 4.7%, P = 0.004 and 5.6%, P \< 0.001, respectively). However, the differences were not statistically significant after adjusting for confounding factors. In a recent study, Wigmore et al. retrospectively investigated 11,395 patients after cancer surgery. After exclusions and propensity matching, 2,607 patients remained in each of the inhalational anesthesia group or total intravenous anesthesia group. The results showed that, after a median follow-up duration of 2.66 years (95% confidence interval \[CI\] 2.62-2.69), volatile inhalational anesthesia was associated with a higher risk for death after both univariate (HR 1.59, 95% CI 1.30-1.95) and multivariable analysis (HR 1.46, 95% CI 1.29-1.66).

However, in this aspect, long-term follow-up results of randomized controlled trials are still lacking. Prospective studies exploring the effect of anesthetic choice on long-term survival in cancer surgery patients are urgently needed.

Impact of Anesthesia Maintenance Methods on Long-term Survival

Impact of Inhalational Versus Intravenous Anesthesia Maintenance Methods on Long-term Survival in Elderly Patients After Cancer Surgery: a Randomized Controlled Trial

Quality of life is assessed with the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30).

Cognitive function is assessed with the Telephone Interview for Cognitive Status-Modified (TICS-m).

Time from surgery to the date of all-cause death.

Time from surgery to the date of cancer recurrence/metastasis or all-cause death, whichever occurs first.

Time from surgery to the date of cancer recurrence/metastasis, new cancer, new serious non-cancer disease, or all-cause death, whichever occurs first.

Hebei Medical University Fourth Hospital

The People's Hospital of Ningxia

Beijing Shijitan Hospital, Capital Medical University

Guizhou Provincial People's Hospital

Affiliated Hospital of Qinghai University

The Third Xiangya Hospital of Central South University

Cancer Hospital of Guangxi Medical University

Shanxi Provincial People's Hospital

Zhongda Hospital

The First Affiliated Hospital of Zhengzhou University

Tang-Du Hospital

Tianjin Nankai Hospital

Shenzhen Second People's Hospital

Peking University First Hospital

Professor and Chairman, Department of Anesthesiology and Critical Care Medicine

Behaviors and Mental Disorders

Nervous System Diseases

Postoperative Complications

Cognitive Dysfunction

Delirium

Postoperative Cognitive Complications

Emergence Delirium

Confusion

Neurobehavioral Manifestations

Neurologic Manifestations

Neurocognitive Disorders

Mental Disorders

Psychotic Disorders

Cognition Disorders

Sevoflurane will be administered by inhalation for anesthesia maintenance. The concentration of inhaled sevoflurane will be adjusted to maintain the bispectral index (BIS) value between 40 and 60. Analgesia will be supplemented with remifentanil (administered by continuous infusion), sufentanil (administered by intermittent injection/continuous infusion), or fentanyl (administered by intermittent injection).

Towards the end of surgery, sevoflurane inhalational concentration will be decreased and fentanyl/sufentanil will be administered when necessary. Sevoflurane inhalation will be stopped at the end of surgery.

Propofol will be administered by intravenous infusion for anesthesia maintenance. The infusion rate of propofol will be adjusted to maintain the BIS value between 40 and 60. Analgesia will be supplemented with remifentanil (administered by continuous infusion), sufentanil (administered by intermittent injection/continuous infusion), or fentanyl (administered by intermittent injection).

Towards the end of surgery, propofol infusion rate will be decreased and fentanyl/sufentanil will be administered when necessary. Propofol infusion will be stopped at the end of surgery.

Surgery is one of the major treatment methods for patients with malignant tumor. And, alone with ageing process, more and more elderly patients undergo surgery for malignant tumor. Evidence emerges that choice of anesthetics, i.e., either inhalational or intravenous anesthetics, may influence the outcome of elderly patients undergoing cancer surgery. Delirium is a commonly occurred early postoperative cognitive complication in the elderly, and its occurrence is associated with the worsening outcomes. Choice anesthetics may influence the occurrence of postoperative delirium. However, evidence in this aspect is conflicting.

It is estimated that 234.2 million major surgical procedures are undertaken every year worldwide. Surgery is one of the major treatment methods for patients with malignant tumor. And, alone with ageing process, more and more elderly patients undergo surgery for malignant tumor. Evidence emerges that choice of anesthetics, i.e., either inhalational or intravenous anesthetics, may influence the outcome of elderly patients undergoing cancer surgery.

Delirium is a commonly occurred cognitive complication in elderly patients after surgery. The occurrence of delirium is associated with the worsening outcomes, including increased morbidity and mortality, prolonged hospital stay, elevated medical care cost, and declined cognitive function. High age, major surgery, and critical illness are major risk factors of postoperative delirium (POD). However, the relationship between use of general anesthetics and occurrence of delirium cannot be excluded.

There are studies that compared the effects of two kinds of anesthetics on the cognitive outcomes after surgery. In the study of Nishikawa et al., 50 elderly (≥ 65 years) patients undergoing long-duration laparoscope-assisted surgery randomly received sevoflurane or propofol anesthesia. The results showed that, although the incidence of POD was not significantly different between the two groups, the delirium rating scale (DRS) score was significantly lower in the sevoflurane group than in the propofol group at postoperative days 2-3 (P = 0.007 and 0.002, respectively). In the study of Schoen et al., 128 patients undergoing on-pump cardiac surgery were randomized into two groups. The results showed that early postoperative cognitive function was significantly better in sevoflurane group than in the propofol group, especially in those who experienced cerebral desaturation during surgery.

On the other hand, some studies reported contrary results. In a large sample size study of 2000 patients undergoing general anesthesia, patients carrying ApoE4 epsilon 4 allele were more likely to develop early postoperative cognitive decline after inhalational anesthesia (odd ratio 3.31, 95% confidence interval 1.25-6.39, P \< 0.05), but not after intravenous anesthesia (odd ratio 0.93, 95% confidence interval 0.37-2.39, P \> 0.05). In a randomized control trail of 44 patients undergoing carotid endarterectomy, the mini-mental state examination (MMSE) score was significantly higher, whereas blood S100B concentration was significantly lower in the propofol group than in the sevoflurane group at 24 hours after surgery. In the study of Tang et al., 200 elderly (≥ 60 years) patients with mild cognitive impairment who planned to undergo radical rectal resection randomly received either sevoflurane or propofol anesthesia. The results showed that, although there was no difference in the incidence of cognitive dysfunction at 7 days after surgery, the negative cognitive effects was more severe after sevoflurane anesthesia than after propofol anesthesia (P = 0.01).

It seems that more evidence suggests the harmful cognitive effects of inhalational anesthetics. However, care must be taken when explaining these results: (1) target patients population were different; (2) sample size were small in the majority of studies; (3) the diagnostic criteria of cognitive complications were different, make it hard to do meta-analysis; (4) the clinical significance the of early postoperative cognitive complication remains to be elucidated.

Impact of Anesthesia Maintenance Methods on Incidence of Postoperative Delirium

Impact of Inhalational Versus Intravenous Anesthesia Maintenance Methods on Incidence of Postoperative Delirium in Elderly Patients After Cancer Surgery: An Open-label, Randomized Controlled Trial

Intensity of pain is assessed twice daily (8-10 AM and 6-8 PM) with the Numeric Rating Scale (an 11-point rating scale where 0 = no pain and 10 = the worst pain).

Subjective sleep quality is assessed once daily (8-10 AM) with the Numeric Rating Scale (an 11-point rating scale where 0 = the worst sleep and 10 = the best sleep).

Cognitive function assessed with a battery of neuropsychological tests before surgery and on the 7th day after surgery. Performed in part of enrolled patients and in control subjects.

Blood samples are taken the day before surgery. Serum 25-hydroxyvitamin D concentration is measured with liquid chromatography-mass spectrometry. Performed in part of enrolled patients.

Delirium is assessed twice daily (8-10 AM and 6-8 PM) with the Confusion Assessment Method for patients without endotracheal intubation or the Confusion Assessment Method for the Intensive Care Unit for patients with endotracheal intubation.

Percentage of intensive care unit (ICU) admission after surgery.

Percentage of ICU admission with endotracheal intubation after surgery.

Length of stay in ICU after surgery (in patients admitted to the ICU after surgery).

Length of stay in hospital after surgery.

Non-delirium complications are defined as newly occurred events other than delirium that are harmful to patients' recovery and required therapeutic intervention, i.e., grade 2 or higher on the Clavien-Dindo classification.

Cognitive function assessed with Telephone Interview for Cognitive Status-Modified (TICS-m).

Surgery is one of the major treatment methods for patients with solid organ cancer. And, alone with the ageing process, more and more elderly patients undergo surgery for cancer. Evidence emerges that choice of anesthetics, i.e., either inhalational or intravenous anesthetics, may influence the outcome of elderly patients undergoing cancer surgery. From the point of view of immune function after surgery and invasiveness of malignant tumor cells, propofol intravenous anesthesia may be superior to inhalational anesthesia. However, the clinical significance of these effects remains unclear. Retrospective studies indicated that use of propofol intravenous anesthesia was associated higher long-term survival rate. Prospective studies exploring the effect of anesthetic choice on long-term survival in cancer surgery patients are urgently needed.

It is estimated that 234.2 million major surgical procedures are undertaken every year worldwide. Surgery is one of the major treatment methods for patients with solid organ cancer. And, alone with the ageing process, more and more elderly patients undergo surgery for cancer. However, evidence emerges that choice of anesthetics, i.e., either inhalational or intravenous anesthetics, may influence the outcome of elderly patients undergoing cancer surgery.

A. Effects of anesthetics on immune function after surgery

The choice of general anesthetics might influence human's immune function after surgery. An international multicenter team investigated the effects of propofol-paravertebral anesthesia vs sevoflurane-opioid anesthesia on the immune function in patients after breast cancer surgery. In a small sample size (n = 32) randomized controlled trail published in 2010, postoperative serum concentrations of interleukin (IL)-1 (protumorigenic cytokine) and matrix metalloproteinases (MMP)-3/9 (associated with cancer cell invasion and metastasis) were significantly lower (P = 0.003 and 0.011, respectively), whereas that of IL-10 (antitumorigenic cytokines) was significantly higher in the propofol group than in the sevoflurane group (P = 0.001). In another small sample size (n = 10) randomized controlled trail published in 2014, serum obtained from patients who received propofol anesthesia led to greater human donor natural killer (NK) cell cytotoxicity in vitro when compared with serum from those who received sevoflurane anesthesia. In a recent small sample size (n = 28) randomized controlled trial, the levels of NK and T helper cell infiltration in breast cancer tissue were significantly higher in patients receiving propofol anesthesia than those receiving sevoflurane anesthesia (P = 0.015 and 0.03, respectively).

Similar findings were reported in patients with other malignant tumors. In a small randomized controlled trial, 30 patients with non-small-cell lung cancer randomly received either propofol or isoflurane anesthesia. The results showed that cluster of differentiation (CD)4+CD28+ percentage (P \< 0.0001) and the ratio of interferon-gamma:interleukin-4 (P = 0.001) all increased significantly with propofol but no change with isoflurane anesthesia; indicating that propofol promotes activation and differentiation of peripheral T-helper cells. In another randomized controlled trial, 60 patients undergoing surgery for tongue cancer surgery randomly received total propofol, mixed (propofol induction and sevoflurane maintenance) anesthesia or total sevoflurane anesthesia. The results showed that the percentages of CD3+, CD3+CD4+, and NK cells and the ratio of CD4+/CD8+ were significantly decreased in the two sevoflurane groups, but not in the total propofol group; suggesting that propofol has less effects on cellular immune response than sevoflurane. There are also studies that reported neutral results.

The above studies suggest that, when compared with inhalational anesthesia, propofol intravenous anesthesia may have favorable effects on the immune function in patients after cancer surgery. However, care must be taken when explaining these results: (1) the sample sizes of the available studies were small; (2) the relationship between postoperative immune function changes and long-term outcomes remains unclear.

B. Effects of anesthetics on invasiveness of malignant tumor

The effects of anesthetics on invasiveness of tumor cells were mainly tested in the experimental studies, i.e., tumor cells were incubated with anesthetics in the in vitro environment. In this aspect, propofol shows somewhat favorable effects. The results of Miao et al. showed that propofol stimulation decreased the expression of MMP-2 and -9 and subsequently decreased the invasive activity of human colon cancer cells, possibly via extracellular signal-regulated kinase 1/2 (ERK1/2) down-regulation mediated through the gamma-aminobutyric acid (GABA)-A receptor. The study of Wang et al. reported that propofol inhibited invasion and metastasis, and enhanced paclitaxel-induced apoptosis of ovarian cancer cells, possibly by suppressing the Slug expression. Ecimovic et al. also reported that propofol reduced migration in both estrogen receptor-positive and -negative breast cancer cells, possibly by suppressing the Neuroepithelial Cell Transforming Gene 1 (NET1) expression.

The reported effects of various inhalational anesthetics are conflicting. Huang et al. compared the effects of propofol and isoflurane on prostate cancer cells. The results showed that propofol, at clinical relevant concentration, inhibited the activation of hypoxia-inducible factor (HIF)-1 alpha, and partially reduced cancer cell malignant activities; whereas isoflurane raised HIF-1 alpha expression, and increased the probability of proliferation and migration. The study of Benaonana et al. reported similar results, i.e., isoflurane up-regulated the expression of HIFs, and increased the growth and malignant potential of renal cancer cells. On the other hand, sevoflurane and desflurane show opposite effects. Multiple studies found that sevoflurane inhibited the proliferation and migration, and induced apoptosis of lung cancer cells. Müller-Edenborn et al. also reported that volatile anesthetics (sevoflurane and desflurane) reduced invasion of colorectal cancer cells through down-regulation of matrix metalloproteinase-9.

So far, the clinical significance of anesthetics on the invasiveness of malignant tumors is still lacking.

C. Effect of anesthetics on long-term outcome after cancer surgery

Studies in this aspect are very limited. In the study of Enlund et al., 2838 patients who underwent breast cancer or colorectal cancer surgery were retrospectively analyzed, among them 1935 received sevoflurane anesthesia and 903 propofol anesthesia. The 1-year and 5-year survival rates were higher in propofol-anesthetized patients than in sevoflurane-anesthetized ones (differences in overall survival rate were 4.7%, P = 0.004 and 5.6%, P \< 0.001, respectively). However, the differences were not statistically significant after adjusting for confounding factors. In a recent study, Wigmore et al. retrospectively investigated 11,395 patients after cancer surgery. After exclusions and propensity matching, 2,607 patients remained in each of the inhalational anesthesia group or total intravenous anesthesia group. The results showed that, after a median follow-up duration of 2.66 years (95% confidence interval 2.62-2.69), volatile inhalational anesthesia was associated with a higher risk for death after both univariate (hazard ratio 1.59, 95% confidence interval 1.30-1.95) and multivariable analysis (hazard ratio 1.46, 95% confidence interval 1.29-1.66).

However, in this aspect, long-term follow-up results of randomized controlled trials are still lacking. Prospective studies exploring the effect of anesthetic choice on long-term survival in cancer surgery patients are urgently needed.

Impact of Anesthesia Maintenance Methods on 5-year Survival After Surgery

Impact of Inhalational Versus Intravenous Anesthesia Maintenance Methods on 5-year Survival in Elderly Patients After Cancer Surgery: a Randomized Controlled Trial

Time from surgery to the date of cancer recurrence/metastasis, new cancer, new serious non-cancer disease (required rehospitalization), or all-cause death, whichever occurs first.

Study title	NCT ID	Conditions	Interventions	Eligibility	Organization
Impact of Anesthesia Maintenance Methods on Long-term Survival	NCT02660411	Aged Neoplasms Surgical Proced... Anesthesia, Inh... Anesthesia, Int... Survival	Sevoflurane Propofol	65 Years - 90 Years	Peking University First Hospital
Impact of Anesthesia Maintenance Methods on Incidence of Postoperative Delirium	NCT02662257	Delirium Postoperative C... Postoperative C...	Sevoflurane Propofol	65 Years - 90 Years	Peking University First Hospital
Impact of Anesthesia Maintenance Methods on 5-year Survival After Surgery	NCT05343260	Aged Neoplasms Surgical Proced... Anesthesia, Inh... Anesthesia, Int... Survival	Sevoflurane Propofol	65 Years - 90 Years	Peking University First Hospital
Impact of Anesthesia Maintenance Methods on Incidence of Postoperative Delirium	NCT02662257	Delirium Postoperative C... Postoperative C...	Sevoflurane Propofol	65 Years - 90 Years	Peking University First Hospital

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