Promotion of interferon-gamma production by natural killer cells via suppression of murine peritoneal macrophage prostaglandin E2 production using intravenous anesthetic propofol

Anesthesia and cancer recurrence: a narrative review

Cancer is a leading cause of death worldwide. With the increasingly aging population, the number of emerging cancer cases is expected to increase markedly in the foreseeable future. Surgical resection with adjuvant therapy is the best available option for the potential cure of many solid tumors; thus, approximately 80% of patients with cancer undergo at least one surgical procedure during their disease. Agents used in general anesthesia can modulate cytokine release, transcription factors, and/or oncogenes. This can affect host immunity and the capability of cancer cells to survive and migrate, not only during surgery but for up to several weeks after surgery. However, it remains unknown whether exposure to anesthetic agents affects cancer recurrence or metastasis. This review explores the current literature to explain whether and how the choice of anesthetic and perioperative medication affect cancer surgery outcomes.

Anaesthesia in Veterinary Oncology: The Effects of Surgery, Volatile and Intravenous Anaesthetics on the Immune System and Tumour Spread

Throughout the course of oncological disease, the majority of patients require surgical, anaesthetic and analgesic intervention. However, during the perioperative period, anaesthetic agents and techniques, surgical tissue trauma, adjuvant drugs for local pain and inflammation and other non-pharmacological factors, such as blood transfusions, hydration, temperature and nutrition, may influence the prognosis of the disease. These factors significantly impact the oncologic patient's immune response, which is the primary barrier to tumour progress, promoting a window of vulnerability for its dissemination and recurrence. More research is required to ascertain which anaesthetics and techniques have immunoprotective and anti-tumour effects, which will contribute to developing novel anaesthetic strategies in veterinary medicine.

The benefits of propofol on cancer treatment: Decipher its modulation code to immunocytes

Anesthetics are essential for cancer surgery, but accumulated research have proven that some anesthetics promote the occurrence of certain cancers, leading to adverse effects in the lives of patients. Although anesthetic technology is mature, there is no golden drug selection standard for surgical cancer treatment. To afford the responsibility of human health, a more specific regimen for cancer resection is indeed necessary. Immunosuppression in oncologic surgery has an adverse influence on the outcomes of patients. The choice of anesthetic strategies influences perioperative immunity. Among anesthetics, propofol has shown positive effects on immunity. Apart from that, propofol's anticancer effect has been generally reported, which makes it more significant in oncologic surgery. However, the immunoregulative function of propofol is not reorganized well. Herein, we have summarized the impact of propofol on different immunocytes, proposed its potential mechanism for the positive effect on cancer immunity, and offered a conceivable hypothesis on its regulation to postoperative inflammation. We conclude that the priority of propofol is high in oncologic surgery and propofol may be a promising immunomodulatory drug for tumor therapy.

Effects of propofol on macrophage activation and function in diseases

Macrophages work with monocytes and dendritic cells to form a monocyte immune system, which constitutes a powerful cornerstone of the immune system with their powerful antigen presentation and phagocytosis. Macrophages play an essential role in infection, inflammation, tumors and other pathological conditions, but these cells also have non-immune functions, such as regulating lipid metabolism and maintaining homeostasis. Propofol is a commonly used intravenous anesthetic in the clinic. Propofol has sedative, hypnotic, anti-inflammatory and anti-oxidation effects, and it participates in the body’s immunity. The regulation of propofol on immune cells, especially macrophages, has a profound effect on the occurrence and development of human diseases. We summarized the effects of propofol on macrophage migration, recruitment, differentiation, polarization, and pyroptosis, and the regulation of these propofol-regulated macrophage functions in inflammation, infection, tumor, and organ reperfusion injury. The influence of propofol on pathology and prognosis via macrophage regulation is also discussed. A better understanding of the effects of propofol on macrophage activation and function in human diseases will provide a new strategy for the application of clinical narcotic drugs and the treatment of diseases.

Effects of Propofol Versus Sevoflurane on Postoperative Breast Cancer Prognosis: A Narrative Review

Perioperative interventions produce substantial biologic perturbations which are associated with the risk of recurrence after cancer surgery. The changes of tumor microenvironment caused by anesthetic drugs received increasing attention. Till now, it’s still unclear whether or not anesthetic drugs may exert positive or negative impact on cancer outcomes after surgery. Breast cancer is the most common tumor and the leading cause of cancer deaths in women. Propofol and sevoflurane are respectively the most commonly used intravenous and inhaled anesthetics. Debates regarding which of the two most commonly used anesthetics may relatively contribute to the recurrence and metastasis vulnerability of breast cancer postoperatively remain. This review aimed to provide a comprehensive view about the effect of propofol versus sevoflurane on the prognosis of breast cancer obtained from pre-clinical studies and clinical studies. Laboratory and animal studies have demonstrated that sevoflurane may enhance the recurrence and metastasis of breast cancer, while propofol is more likely to reduce the activity of breast cancer cells by attenuating the suppression of the immune system, promoting tumor cells apoptosis, and through other direct anti-tumor effects. However, retrospective clinical studies have shown contradictory results about the effects of propofol and sevoflurane on long-term survival in breast cancer patients. Furthermore, recent prospective studies did not identify significant differences between propofol and sevoflurane in breast cancer metastasis and recurrence. Therefore, more preclinical studies and randomized controlled studies are needed to guide the choice of anesthetics for breast cancer patients.

Impact of anesthetics on oncogenic signaling network: a review on propofol and isoflurane

Propofol as an intravenous anesthetic and isoflurane as an inhalational/volatile anesthetic continue to be an important part of surgical anesthetic interventions worldwide. The impact of these anesthetics on tumor progression, immune modulation, and survival rates of cancer patients has been widely investigated. Although most of the preclinical studies have provided a beneficial effect of propofol over isoflurane or other volatile anesthetics, several investigations have shown contradictory results, which warrant more preclinical and clinical studies. Propofol mostly exhibits antitumor properties, whereas isoflurane being a cost-effective anesthetic is frequently used. However, isoflurane has been also reported with protumorigenic activity. This review provides an overall perspective on the network of signaling pathways that may modulate several steps of tumor progression from inflammation, immunomodulation, epithelial-mesenchymal transition (EMT) to invasion, metastasis, angiogenesis, and cancer stemness and extracellular vesicles along with chemotherapeutic applications and clinical status of these anesthetics. A clear understanding of the mechanistic viewpoints of these anesthetics may pave the way for more prospective clinical trials with the ultimate goal of obtaining a safe and optimal anesthetic intervention that would prevent cancer recurrence and may influence better postoperative survival.

The impact of alfaxalone, propofol and ketamine on canine peripheral blood lymphocyte cytotoxicity in vitro

Anesthetics may worsen the outcome of patients undergoing oncologic surgery via immune suppression. This study examines the impact of propofol, ketamine, and alfaxalone on canine peripheral blood lymphocyte (PBL) cytotoxic function in vitro. PBLs isolated from healthy canine blood were cultured in the presence or absence of alfaxalone, propofol, ketamine, their carrier solutions or dexamethasone as a positive control for 20 h. There was a decrease in cytotoxicity in PBLs exposed to dexamethasone and propofol carrier compared to the control as assessed by means of a chromium-based cytotoxicity assay. The PBLs exposed to propofol carrier also showed lower cytotoxicity compared to propofol. No other significant differences were observed. Therefore, the documented effects of these anesthetics in vivo may be caused by an indirect mechanism. The lipid emulsion's significant decrease in PBL cytotoxicity may have implications for critically ill patients on total parenteral nutrition.

Impact of anesthesia and analgesia techniques on glioblastoma progression. A narrative review

Glioblastoma (GBM) is an aggressive malignant CNS tumor with a median survival of 15 months after diagnosis. Standard therapy for GBM includes surgical resection, radiation, and temozolomide. Recently, anesthetics and analgesics have received attention for their potential involvement in mediating tumor growth. This narrative review investigated whether various members of the 2 aforementioned classes of drugs have a definitive impact on GBM progression by summarizing pertinent in vitro, in vivo, and clinical studies. Recent publications regarding general anesthetics have been inconsistent, showing that they can be pro-tumoral or antitumoral depending on the experimental context. The local anesthetic lidocaine has shown consistent antitumoral effects in vitro. Clinical studies looking at anesthetics have not concluded that their use improves patient outcomes. In vitro and in vivo studies looking at opioid involvement in GBM have demonstrated inconsistent findings regarding whether these drugs are pro-tumoral or antitumoral. Nonsteroidal anti-inflammatory drugs, and specifically COX-2 inhibitors, have shown inconsistent findings across multiple studies looking at whether they are beneficial in halting GBM progression. Until multiple repeatable studies show that anesthetics and analgesics can suppress GBM growth, there is no strong evidence to recommend changes in the anesthetic care of these patients.

Outpatient breast-conserving surgery for breast cancer: Use of local and intravenous anesthesia and/or sedation may reduce recurrence and improve survival

The use of general anesthesia (GA) with inhalational anesthetics for breast cancer surgery may be associated with breast cancer recurrence and increased mortality due to the immunosuppressive effects of these drugs. Less-immunosuppressive anesthetic techniques may reduce breast cancer recurrence. We evaluated the feasibility, safety, and efficacy of outpatient breast-conserving surgery (BCS) for breast cancer in a breast clinic in terms of the anesthetic technique used, complications occurring, recurrence, and survival. Methods: The sample comprised 456 consecutive patients with stage 0–III breast cancer who underwent BCS/axillary lymph node (ALN) management using local and intravenous anesthesia and/or sedation between May 2008 and January 2020. Most patients received adjuvant chemotherapy and/or endocrine therapy and radiotherapy after surgery. Patient outcomes were evaluated retrospectively. Results: All patients recovered and were discharged after resting for 3–4 h postoperatively. No procedure-related severe complication or death occurred. Sixty-four complications (14.0%) were observed: 14 wound infections, 17 hematomas, and 33 axillary lymphoceles. The median follow-up period was 2259 days (range, 9–4190 days), during which disease recurrence was observed in 25 (5.4%) patients. The overall survival and breast cancer–specific survival rates were 92.3% and 94.7%, respectively. Conclusions: Outpatient surgery for breast cancer involving BCS and ALN management under local and intravenous anesthesia and/or sedation can be performed safely, without serious complication or death. Less-immunosuppressive anesthetic techniques with spontaneous breathing may reduce the recurrence of breast cancer and improve survival relative to GA.

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Outpatient surgery for breast cancer involving breast-conserving surgery (BCS) and axillary lymph node (ALN) management under local and intravenous anesthesia and/or sedation can be performed safely.

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Less-immunosuppressive anesthetic techniques with spontaneous breathing may reduce the recurrence of breast cancer and improve survival compared with general anesthesia.

Can anesthetics affect bladder cancer recurrence? Total intravenous versus volatile anesthesia in patients undergoing robot-assisted radical cystectomy: A single institution retrospective analysis

BACKGROUND

Radical cystectomy is standard of care and part of a multidisciplinary approach for long-term survival in patients with muscle-invasive bladder cancer (MIBC) or high-grade non-MIBC. Recent data have suggested that anesthetic technique can affect long-term survival and recurrence in patients undergoing cancer related surgery.

METHODS

The records of all patients who underwent robot-assisted radical cystectomy for high-risk non-MIBC or MIBC at a single academic institution from 2014 to 2020 were retrospectively reviewed. Patients were grouped according to whether they received total intravenous (TIVA) or volatile inhalation anesthesia (VIA). Univariable and multivariable cox proportional hazards models were used to compare hazard ratios for distant recurrence. Kaplan-Meier recurrence-free survival curves were constructed from the date of surgery to recurrence.

RESULTS

A total of 231 patients were included, of which 126 (55%) received TIVA and 105 (45%) received VIA. Distant recurrence occurred in 8.7% and 26.7% of patients who received TIVA and VIA, respectively (P < 0.001). Kaplan-Meier analysis demonstrated significant improvement in distant recurrence-free survival with TIVA (log-rank P < 0.001). Multivariable analysis revealed a significant increase in recurrence risk with VIA (HR: 3.4, 95%CI: 1.5-7.7, P < 0.01) and increasing tumor pathological stage (pT2, pT3, pT4, all P < 0.05).

CONCLUSIONS

The use of volatile inhalation anesthetics during robot-assisted radical cystectomy may be associated with an increased risk of distant recurrence. Further studies will be necessary to validate these findings.

Aryl Hydrocarbon Receptor Role in Co-Ordinating SARS-CoV-2 Entry and Symptomatology: Linking Cytotoxicity Changes in COVID-19 and Cancers; Modulation by Racial Discrimination Stress

There is an under-recognized role of the aryl hydrocarbon receptor (AhR) in co-ordinating the entry and pathophysiology of the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) that underpins the COVID-19 pandemic. The rise in pro-inflammatory cytokines during the 'cytokine storm' induce indoleamine 2,3-dioxygenase (IDO), leading to an increase in kynurenine that activates the AhR, thereby heightening the initial pro-inflammatory cytokine phase and suppressing the endogenous anti-viral response. Such AhR-driven changes underpin the heightened severity and fatality associated with pre-existent high-risk medical conditions, such as type II diabetes, as well as to how racial discrimination stress contributes to the raised severity/fatality in people from the Black Asian and Minority Ethnic (BAME) communities. The AhR is pivotal in modulating mitochondrial metabolism and co-ordinating specialized, pro-resolving mediators (SPMs), the melatonergic pathways, acetyl-coenzyme A, and the cyclooxygenase (COX) 2-prostaglandin (PG) E2 pathway that underpin 'exhaustion' in the endogenous anti-viral cells, paralleling similar metabolic suppression in cytolytic immune cells that is evident across all cancers. The pro-inflammatory cytokine induced gut permeability/dysbiosis and suppression of pineal melatonin are aspects of the wider pathophysiological underpinnings regulated by the AhR. This has a number of prophylactic and treatment implications for SARS-CoV-2 infection and cancers and future research directions that better investigate the biological underpinnings of social processes and how these may drive health disparities.

Anesthesia Options and the Recurrence of Cancer: What We Know so Far?

Surgery is a critical period in the survival of patients with cancer. While resective surgery of primary tumors has shown to prolong the life of these patients, it can also promote mechanisms associated with metastatic progression. During surgery, patients require general and sometimes local anesthetics that also modulate mechanisms that can favor or reduce metastasis. In this narrative review, we summarized the evidence about the impact of local, regional and general anesthesia on metastatic mechanisms and the survival of patients. The available evidence suggests that cancer recurrence is not significantly impacted by neither regional anesthesia nor volatile or total intravenous anesthesia.

Retrospective Comparison between the Effects of Propofol and Inhalation Anesthetics on Postoperative Recurrence of Early- and Intermediate-Stage Hepatocellular Carcinoma

OBJECTIVE

Previous studies have reported that propofol has antitumor, anti-inflammatory, and antioxidant effects in addition to its anesthetic properties. To confirm this, a retrospective investigation was conducted to determine whether different anesthetic agents, particularly propofol and inhalation anesthetics, have an effect on the recurrence of hepatocellular carcinoma (HCC) in patients who were diagnosed with primary HCC and underwent laparoscopic hepatectomy.

SUBJECTS AND METHODS

Patients with Barcelona Clinic Liver Cancer stages 0, A, and B HCC, who underwent laparoscopic hepatic resection, were enrolled in this study. Post-operative HCC recurrence, which was determined from postoperative liver CT, was evaluated 24 months postoperatively with respect to the main anesthetic agents. The characteristics of HCC and other patient-related or surgery-related variables were evaluated together.

RESULTS AND CONCLUSION

During the 24-month period after hepatic resection, less HCC patients in the propofol group than in the inhalation group recurred (p = 0.046). The mean time to recurrence was 20.8 months (95% CI, 19.7-22.0) and 19.1 months (95% CI, 17.8-20.4) in the propofol group and the inhalation group, respectively. In addition, multivariable Cox proportional regression analysis revealed that the propofol group showed significantly decreased recurrence versus the inhalation group (hazard ratio, 0.57; 95% CI, 0.47-0.69; p = 0.029). When propofol was used as the main general anesthetic agent for laparoscopic hepatic resection, the postoperative 2-year recurrence rate decreased in early- and intermediate-stage HCC.

Effects of propofol/remifentanil-based total intravenous anesthesia versus sevoflurane-based inhalational anesthesia on the release of VEGF-C and TGF-β and prognosis after breast cancer surgery: a prospective, randomized and controlled study

Background

Vascular endothelial growth factor (VEGF) and transforming growth factor-β (TGF-β) have been involved in tumor growth and metastasis. Sevoflurane may promote angiogenesis, whereas propofol can present an anti-angiogenic effect. In this study, we compared the effects of propofol/remifentanil-based total intravenous anesthesia (TIVA) and sevoflurane-based inhalational anesthesia on the release of VEGF-C and TGF-β, as well as recurrence- free survival (RFS) rates in the patients undergoing breast cancer surgery.

Methods

Eighty female patients undergoing breast cancer resection were enrolled and randomized to receive either sevoflurane-based inhalational anesthesia (SEV group) or propofol/remifentanil-based TIVA (TIVA group). The serum concentrations of VEGF-C and TGF-β before and 24 h after surgery were measured and RFS rates over a two-year follow-up were analyzed in both groups. The postoperative pain scores assessed using a visual analogue scale (VAS) and the use of perioperative opioids were also evaluated.

Results

Although VAS scores at 2 h and 24 h after surgery were comparable between the two groups, there were more patients receiving postoperative fentanyl in the TIVA group (16[40%]) compared with the SEV group (6[15%], p = 0.023). VEGF-C serum concentrations increased after surgery from 105 (87–193) pg/ml to174 (111–281) pg/ml in the SEV group (P = 0.009), but remained almost unchanged in the TIVA group with 134 (80–205) pg/ml vs.140(92–250) pg/ml(P = 0.402). The preoperative to postoperative change for VEGF-C of the SEV group (50 pg/ml) was significantly higher than that of the TIVA group (12 pg/ml) with a difference of 46 (− 11–113) pg/ml (P = 0.008). There were also no significant differences in the preoperative and postoperative TGF-β concentrations between the two groups. The two-year RFS rates were 78% and 95% in the SEV and TIVA groups (P = 0.221), respectively.

Conclusion

In comparison with sevoflurane-based inhalational anesthesia, propofol/remifentanil -based total intravenous anesthesia can effectively inhibit the release of VEGF-C induced by breast surgery, but didn’t seem to be beneficial in the short-term recurrence rate of breast cancer.

Trial registration

Chictr.org.cn ChiCTR1800017910. Retrospectively Registered (Date of registration: August 20, 2018).

The Relationship Between Sedatives, Sedative Strategy, and Healthcare-Associated Infection: A Systematic Review

BACKGROUND Healthcare-associated infections (HAIs) cause significant morbidity in critically ill patients. An underappreciated but potentially modifiable risk factor for infection is sedation strategy. Recent trials suggest that choice of sedative agent, depth of sedation, and sedative management can influence HAI risk in mechanically ventilated patients. OBJECTIVE To better characterize the relationships between sedation strategies and infection. METHODS Systematic literature review. RESULTS We found 500 articles and accepted 70 for review. The 3 most common sedatives for mechanically ventilated patients (benzodiazepines, propofol, and dexmedetomidine) have different pharmacologic and immunomodulatory effects that may impact infection risk. Clinical data are limited but retrospective observational series have found associations between sedative use and pneumonia whereas prospective studies of sedative interruptions have reported possible decreases in bloodstream infections, pneumonia, and ventilator-associated events. CONCLUSION Infection rates appear to be highest with benzodiazepines, intermediate with propofol, and lowest with dexmedetomidine. More data are needed but studies thus far suggest that a better understanding of sedation practices and infection risk may help hospital epidemiologists and critical care practitioners find new ways to mitigate infection risk in critically ill patients. Infect Control Hosp Epidemiol 2016;1-9.

Effects of propofol-based total intravenous anesthesia on recurrence and overall survival in patients after modified radical mastectomy: a retrospective study

Background

The optimal combination of anesthetic agent and technique may have an influence on long-term outcomes in cancer surgery. In vitro and in vivo studies suggest that propofol independently reduces migration of cancer cells and metastasis. Thus, the authors retrospectively examined the link between propofol-based total intravenous anesthesia (TIVA) and recurrence or overall survival in patients undergoing modified radical mastectomy (MRM).

Methods

A retrospective analysis of the electronic database of all patients undergoing MRM for breast cancer between January 2007 and December 2008 was undertaken. Patients received either propofol-based TIVA (propofol group) or sevoflurane-based anesthesia (sevoflurane group). We analyzed prognostic factors of breast cancer and perioperative factors and compared recurrence-free survival and overall survival between propofol and sevoflurane groups.

Results

A total of 363 MRMs were carried out during the period of the trial; 325 cases were suitable for analysis (173 cases of propofol group, and 152 cases of sevoflurane group). There were insignificant differences between the groups in age, weight, height, histopathologic results, surgical time, or postoperative treatment (chemotherapy, hormonal therapy, and radiotherapy). The use of opioids during the perioperative period was greater in propofol group than in sevoflurane group. Overall survival was no difference between the two groups. Propofol group showed a lower rate of cancer recurrence (P = 0.037), with an estimated hazard ratio of 0.550 (95% CI 0.311–0.973).

Conclusions

This retrospective study provides the possibility that propofol-based TIVA for breast cancer surgery can reduce the risk of recurrence during the initial 5 years after MRM.

Anesthesia, surgical stress, and "long-term" outcomes

An increasing body of evidence shows that the choice of anesthetic can strongly influence more than simply the quality of anesthesia. Regional and general anesthesia have often been compared to ascertain whether one provides benefits through dampening the stress response or harms by accelerating cancer progression. Regional anesthesia offers considerable advantages, by suppressing cortisol and catecholamine levels and reducing muscle breakdown postoperatively. It also has less immunosuppressive effect and potentially reduces the proinflammatory cytokine response. As such, vital organ functions (e.g., brain and kidney) may be better preserved with regional anesthetics, however, further study is needed. Volatile general anesthetics appear to promote cancer malignancy in comparison to regional and intravenous general anesthetics, and reduce the body's ability to act against cancer cells by suppression of natural killer cell activity. There is not sufficient evidence to support an alteration of current clinical practice, however, further research into this area is warranted due to the potential implications elicited by current studies.

Intravenous anesthetic propofol suppresses prostaglandin E2 and cysteinyl leukotriene production and reduces edema formation in arachidonic acid-induced ear inflammation

Propofol is an intravenous drug widely used for anesthesia and sedation. Previously, propofol was shown to inhibit cyclo-oxygenase (COX) and 5-lipoxygenase (5-LOX) activities. Because these enzyme-inhibiting effects have only been demonstrated in vitro, this study sought to ascertain whether similar effects might also be observed in vivo. In the current studies, effects of propofol were tested in a murine model of arachidonic acid-induced ear inflammation. Specifically, propofol - as a pre-treatment -- was intraperitoneally and then topical application of arachidonic acid was performed. After 1 h, tissue biopsies were collected and tested for the presence of edema and for levels of inflammatory mediators. The results indicated that the administration of propofol significantly suppressed ear edema formation, tissue myeloperoxidase activity, and tissue production of both prostaglandin E2 and cysteinyl leukotrienes. From the data, it can be concluded that propofol could exert anti-COX and anti-5-LOX activities in an in vivo model and that these activities in turn could have, at least in part, suppressed arachidonic acid-induced edema formation in the ear.

The immune response to anesthesia: part 2 sedatives, opioids, and injectable anesthetic agents

OBJECTIVE

To review the immune response to injectable anesthetics and sedatives and to compare the immunomodulatory properties between inhalation and injectable anesthetic protocols.

STUDY DESIGN

Review.

METHODS AND DATABASES

Multiple literature searches were performed using PubMed and Google Scholar from March 2012 through November 2013. Relevant anesthetic and immune terms were used to search databases without year published or species constraints. The online database for Veterinary Anaesthesia and Analgesia and the Journal of Veterinary Emergency and Critical Care were searched by issue starting in 2000 for relevant articles.

CONCLUSION

Sedatives, injectable anesthetics, opioids, and local anesthetics have immunomodulatory effects that may have positive or negative consequences on disease processes such as endotoxemia, generalized sepsis, tumor growth and metastasis, and ischemia-reperfusion injury. Therefore, anesthetists should consider the immunomodulatory effects of anesthetic drugs when designing anesthetic protocols for their patients.

Effects of different general anaesthetic techniques on immune responses in patients undergoing surgery for tongue cancer

The aim of this study was to investigate the effects of different general anaesthesia techniques on immune responses in patients undergoing surgery for tongue cancer. Sixty American Society of Anesthesiologists physical status 1 or 2 patients undergoing elective reconstructive surgery for tongue cancer were randomised to three groups. Group 1 received propofol induction and maintenance (TIVA), group 2 received propofol induction and sevoflurane maintenance (MIXED) and group 3 received sevoflurane induction and maintenance (SEVO). All patients received an infusion of remifentanil. Blood samples were obtained at eight time-points: 30 minutes before induction (T0); one hour (T1), three hours (T2) and five hours (T3) after induction; at the end of the operation (T4); and 24 hours (T5), 48 hours (T6) and 72 hours (T7) after operation. The T lymphocyte subsets (including CD3(+) cells, CD3(+)CD4(+) cells and CD3(+)CD8(+)cells) and CD4(+)/CD8(+) ratio, natural killer cells and B lymphocytes were analysed by flow cytometry. All immunological indicators except CD3(+)CD8(+) cells were significantly decreased in all groups at T1~T5 compared to T0 (P <0.05). The percentages of CD3(+) cells, CD3(+)CD4(+) cells and natural killer cells, and the CD4(+)/CD8(+) ratios were significantly lower in the MIXED groups and SEVO groups but not the TIVA group at T6 as compared with T0 (P <0.05). There were minor but statistically significant differences in the percentages of CD3(+) cells, CD3(+)CD4(+) cells and natural killer cells, and the CD4(+)/CD8(+) ratios between the SEVO group and the TIVA group at T2approxT6 (P <0.05). These findings suggest that propofol has slightly less effect on cellular immune responses than sevoflurane.

Effect of propofol on prostaglandin E2 production and prostaglandin synthase-2 and cyclooxygenase-2 expressions in amniotic membrane cells

PURPOSE

Surgery during pregnancy can be a cause of preterm labor or birth, possibly resulting from anesthetic agents or direct effects of surgery. This study was aimed to investigate the effect of propofol on uterine contractility by examining prostaglandin E2 (PGE2) production and the expression of PGE synthase 2 (PGES2) and cyclooxygenase-2 (COX-2) in amniotic membrane cells.

METHODS

Amniotic membranes were collected from healthy full-term women who underwent cesarean section at 37-40 weeks of gestation. The amniotic cells were cultured in α-modified-Eagle's medium with 10% fetal bovine serum for 24 h at 5% CO2 in a 37 °C incubator. Then, various doses of propofol (0.01-10 μg/ml) were used for treatment for 3 h. PGE2 concentrations in conditioned media were evaluated using ELISA. PGES2 and COX-2 expression were examined using RT-PCR and Western blot. Cell viability and apoptosis were examined by MTT, ATP assays, and the TUNEL method.

RESULTS

PGE2 production significantly decreased at 0.1 and 1.0 μg/ml propofol concentrations compared to controls. COX-2 and PGES2 mRNA expression was decreased in a dose-dependent manner with a significant difference at 0.1 μg/ml propofol compared to controls. The protein expression of COX-2 showed a similar result to mRNA expression, but protein expression of PGES2 was not significantly decreased. No effect of propofol was found in cell viability.

CONCLUSIONS

This study showed that propofol reduced the production of PGE2 and the expression of COX-2 and PGES2 without affecting cell viability.

Immunosuppressive aspects of analgesics and sedatives used in mechanically ventilated patients: an underappreciated risk factor for the development of ventilator-associated pneumonia in critically ill patients

OBJECTIVE

To evaluate the evidence describing the immunosuppressive and pharmacokinetic properties of commonly used analgesic and sedation agents in critically ill patients.

DATA SOURCES

MEDLINE (January 1980-September 2013) was searched.

STUDY SELECTION AND DATA EXTRACTION

All in vitro and in vivo studies that evaluated the immune-modulating properties of analgesic and sedation agents commonly used in the critically ill were included. Full-text and abstract-only articles (noted) were included in this review. Inclusion criteria were met by 46 studies and were evaluated.

DATA SYNTHESIS

Analgesic and sedation agents have been shown to be immunosuppressive in a variety of models. In vitro models use a variety of immune cells to demonstrate the immunosuppressive properties of opioids, benzodiazepines, and to a lesser extent, propofol. In each case, animal studies provide more robust data supporting the concept that opioids, benzodiazepines, and propofol exhibit immunosuppressive activities ranging from innate to adaptive immune alterations. Human studies, though more limited, provide further support that these agents inhibit the immune response. In contrast, data have shown that dexmedetomidine may attenuate the immune system. Clinical trial data evaluating the immunosuppressive properties of these agents is limited.

CONCLUSIONS

Analgesic and sedation agents have clearly been shown to alter cellular function and other mediators of the immune system; yet the clinical impact remains to be fully elucidated. The mechanism by which sedation interruption reduces ventilator-associated pneumonia may in fact be a reduction in immunosuppressive effects. Studies linking the immune-modulating effects of analgesic and sedation agents in critically ill patients are needed.

Intravenous anesthetic propofol suppresses prostaglandin E2 production in murine dendritic cells

Propofol is an intravenous anesthetic that is widely used for anesthesia and sedation. Dendritic cells (DC) are one of the crucial immune cells that bridge innate and adaptive immunity, in which DC process antigens during innate immune responses to present them to naïve T-cells, leading to an establishment of adaptive immunity. Prostaglandin (PG)-E(2) may be secreted by DC into the microenvironment, considerably influencing DC phenotype and function, and thus determining the fate of adaptive immunity. Since propofol suppresses PGE(2) production in murine macrophages, the primary purpose of the present study was to determine whether propofol also suppresses PGE(2) production in DC. Assuming a positive finding of such suppression, we tested whether this also leads to alterations of interleukin (IL)-12 and IL-10 production and DC surface marker expression, both of which can be modulated by PGE(2). In bone marrow-derived DC, propofol significantly suppressed the PGE(2) production after lipopolysaccharide stimulation. Cyclo-oxygenase (COX) protein expression and arachidonic acid release were unaffected, while COX enzyme activity was significantly inhibited by propofol. The propofol-induced COX inhibition did not lead to the increased production of cysteinyl leukotrienes and leukotriene-B(4). Endogenous COX inhibition with propofol, as well as with the selective COX-2 inhibitor, NS-398, did not affect IL-12 and IL-10 production from DC. The surface expression of I-A(b) and CD40 on DC was not changed, while that of CD86 slightly increased, with both propofol and NS-398; expression of CD80 was not affected with propofol, but increased slightly with NS-398. Finally, endogenous COX inhibition with either propofol or NS-398 did not significantly affect the ability of DC to induce allogeneic T-cell proliferation. It is concluded that the intravenous anesthetic propofol suppresses COX enzyme activity in DC, with no consequences with respect to IL-12/IL-10 production and allogeneic T-cell proliferation, while minimal consequences were observed in surface molecule expression.