Effects of different preparations of propofol, diazepam, and etomidate on human neutrophils in vitro

Evaluation of the effect of lidocaine epidural injection on immunological indices in dogs under total intravenous anesthesia submitted to ovariohysterectomy

This study aimed to evaluate the effects of epidural anaesthesia with lidocaine in combination with general anaesthesia with propofol on some immunologic indices in dogs undergoing ovariohysterectomy. Twelve adult dogs were anesthetized with propofol (induction: 7 mg/kg; maintenance: 0.4 mg/kg/min) and were then allocated into either groups of epidural saline (control) or epidural lidocaine (4 mg/kg; treatment). All the included animals underwent ovariohysterectomy operation. The immune responses, hematologic parameters and cortisol levels were assessed in the predetermined intervals. Evaluation of the innate immunity revealed higher significant levels in the bactericidal, lysozyme and myeloperoxidase activities at 4 hours after surgery in the treatment. In the humoral immunity, the total immunoglobulin level was significantly higher in the treatment. In the assessment of cellular immunity, higher significant values were detected in the delayed skin sensitivity to phytohemagglutinine injection after 48 and 72 hours in the treatment. Moreover, higher significant levels were observed in the number and percentage of lymphocytes as well as an increase in the percentage of monocytes in the treatment at 4 hours after the operation. Notably, the cortisol hormone in the treatment was lower than control at 4 hours of the surgery. In conclusion, epidural anaesthesia with lidocaine when added to general anaesthesia with propofol attenuated the suppression of the innate and cellular immune responses produced by anaesthesia and surgery in the dogs.

A Critical Appraisal of the Effects of Anesthetics on Immune-system Modulation in Critically Ill Patients With COVID-19

Purpose

The aim of the present article was to briefly summarize current knowledge about the immunomodulatory effects of general anesthetics and the possible clinical effects of this immunomodulation in patients with COVID-19.

Methods

The PubMed, Scopus, and Google Scholar databases were comprehensively searched for relevant studies.

Findings

The novel coronavirus causes a wide spectrum of clinical manifestations, with a large absolute number of patients experiencing severe pneumonia and rapid progression to acute respiratory distress syndrome and multiple organ failure. In these patients, the equilibrium of the inflammatory response is a major determinant of survival. The impact of anesthetics on immune-system modulation may vary and includes both pro-inflammatory and anti-inflammatory effects.

Implications

Inhibition of the development of severe inflammation and/or the enhancement of inflammation resolution by anesthetics may limit organ damage and improve outcomes in patients with COVID-19.

[Perioperative tumour dissemination. 2. Effects of anaesthesia and analgesia]

There has been growing concern over the last few years on the effect that the anaesthetic drugs used during oncological surgery could have on long-term tumour progression. In laboratory studies, it has been observed how some substances used during the anaesthetic procedure influence tumour immunosurveillance, cell proliferation or tumour angiogenesis processes. The possible clinical relevance of the anaesthetic technique used as regards long-term tumour progression and survival is still to be determined. However, based on retrospective studies, it appears that those anaesthetic techniques combined with the use of regional anaesthesia and analgesia may be beneficial compared to those that are maintained on the use of opioids. Further research should help to clarify the long-term clinical relevance of the anaesthetic process during oncological surgery.

Effects of desflurane, sevoflurane and propofol on phagocytosis and respiratory burst activity of human polymorphonuclear leucocytes in bronchoalveolar lavage

BACKGROUND AND OBJECTIVE

In polymorphonuclear leucocytes, phagocytosis and respiratory burst activity are mainly responsible for bacterial killing. We aimed to investigate the effects of anaesthesia with desflurane, sevoflurane and propofol on these functional activities of polymorphonuclear leucocytes in bronchoalveolar lavage fluid.

METHODS

Sixty patients scheduled to have tympanoplasty surgery were studied. The patients were divided into three groups (group D, desflurane; group S, sevoflurane; group P, propofol). Anaesthesia was induced with propofol, fentanyl and rocuronium in all groups. Anaesthesia was maintained with inhalation agent or propofol. Bronchoalveolar lavage was performed immediately after induction of anaesthesia and after surgical procedure by a fibreoptic bronchoscope. Leucocyte respiratory burst and phagocytic activity in bronchoalveolar lavage fluid were determined by flow cytometric analysis of gated leucocyte populations within 2 h after each bronchoalveolar lavage sample. Changes in leucocyte functions with time were expressed as mean fluorescence intensity.

RESULTS

There were no significant differences in phagocytic activity of polymorphonuclear leucocytes within and between the groups. The respiratory burst function of polymorphonuclear leucocytes showed a significant increase after surgery in group P (P < 0.05). When we compared the differences between the three groups, we found the difference in mean fluorescence intensity as statistically significant between group P and group S.

CONCLUSION

This study showed that propofol anaesthesia increased the respiratory burst function of polymorphonuclear leucocytes in bronchoalveolar lavage fluid.

Effects of sevoflurane and propofol on wound healing in rats: comparison of blood flow and wound size

BACKGROUND

As the wound healing is a multi-factorial process, the anesthetic agent and the duration of its exposure may influence the healing process after surgery. This study investigated the effect of anesthetic agents and duration of its exposure on the wound healing process after operation.

METHODS

Total 32 rats weighing 200-300 g were randomly allocated to one of eight groups according to the exposure time (1, 2, 4, 8 hours) of sevoflurane or propofol (n = 4 each). After wounding under the each anesthetic, anesthesia was maintained for 1, 2, 4 and 8 hours in each group. We compared the skin blood flow around the wound and the wound size at baseline, 3 days, and 7 days postoperatively.

RESULTS

In sevoflurane group, short exposure group (1, 2 hours) showed higher wound blood flow than long exposure (4, 8 hours) at 3 days after wounding (P < 0.05), but not at 7 days after wounding. For the wound size, there was no difference at 3 days after wounding in sevoflurane group, but 8 hours exposure group had the largest wound at 7 days after wounding. In propofol group, wound blood flow showed no difference at 3 days after wounding, but that of 4, 8 hours exposure group was higher than 2 hours exposure group at 7 days after wounding. There was no difference in wound size in propofol group.

CONCLUSIONS

This study implicates that sevoflurane might influence the wound healing process more prominently than propofol according to the duration of exposure time.

Cell-dependent influence on the phagocytosis induced by non-ionic contrast medium injection

Iodinated contrast media (CM) can inhibit phagocytosis. To better understand the importance of this effect upon the elementary defence mechanism, the aim of the study was to compare the in vivo effect of non-ionic CM on the engulfing ability of peripheral blood phagocytic cells from patients undergoing CM-enhanced CT. Neutrophil granulocytes and monocytes from patients' peripheral blood obtained before and 30 min after CM injection were incubated with fluorescent-labelled Escherichia coli bacteria. Both the percentage of cells that engulfed bacteria and the phagocytic activity per cell has been determined by flow cytometry. We found that phagocytosis was greater in neutrophils than in monocytes. CM decreased the percentage of monocytes phagocyting bacteria, both at 4 degrees C (20.3%+/-3.3% versus 16.1%+/-2.0%; p<0.03) and at 37 degrees C (51.6%+/-4.1% versus 47.5%+/-2.6%; p>0.05), and increased the percentage of neutrophils at 4 degrees C (11.8%+/-2.1% versus 14.3%+/-2.2%; p<0.002) and at 37 degrees C (83.1%+/-3.6% versus 85.1%+/-3.2%; p>0.05). The phagocytic activity decreased significantly at 37 degrees C in monocytes (p<0.02), and was not affected in neutrophils. CM injection has different effects on both the percentage of phagocytosing cells and the phagocytic activity in monocytes and neutrophils. The inhibitory effect on monocyte phagocytosis seems to be compensated by neutrophils.

Anaesthetics and immune function

Surgical trauma and anaesthetics may cause immune suppression, predisposing patients to postoperative infections. Furthermore, stress such as surgery and pain per se is associated with immune suppression which, in animal models, leads to an increased susceptibility to infection and tumour spread. Thus, by modulating the neurohumoral stress response, anaesthesia may indirectly affect the immune system of surgical patients. In particular, regional anaesthesia attenuates this stress response and the associated effects on cellular and humoral immunity. Additionally, anaesthetics may directly affect the functions of immune-competent cells. However, the reported effects of commercial preparations of, for example, propofol, etomidate and midazolam are highly dependent on the applied solvent. Immunosuppressive effects may be particularly relevant in the intensive care unit when anaesthetics are used as long-term sedatives. There is a striking body of evidence that long-term exposure to certain sedatives is paralleled by infectious complications. On the other hand, anti-inflammatory effects of anaesthetics may be therapeutically beneficial in distinct situations such as those involving ischaemia/reperfusion injury or the systemic inflammatory response syndrome. Consequently, sedatives should be administered with careful regard to their respective potential immunomodulatory properties, the clinical situation, and the immunity status of the critically ill patient.

Inhibition of the neutrophil oxidative response by propofol

BACKGROUND AND OBJECTIVE

Propofol has been shown to inhibit a variety of functions of neutrophils in vitro, but there is a lack of in vivo data. To analyse the effects of propofol on neutrophil function in vivo we chose to investigate cataract surgery since it represents a small surgical procedure with minimal immunomodulatory effects induced by surgery. We sought to analyse any immunosuppressive effects of propofol after short-term administration in vivo in comparison to local anaesthesia as well as to in vitro effects of propofol.

METHODS

The study was designed as an open randomized trial enrolling 20 patients undergoing general or local anaesthesia. The neutrophil oxidative response and propofol plasma concentration were assessed prior, during and after anaesthesia. Neutrophil function was determined flow cytometrically based on dihydrorhodamine 123 oxidation.

RESULTS

Propofol concentrations which yielded a marked suppression in vitro did not alter the neutrophil oxidative response during cataract surgery in vivo. However, after local anaesthesia the neutrophil oxidative response declined to 37%, compared to the control response prior to anaesthesia.

CONCLUSIONS

Although we could detect the well established suppression of neutrophil function by propofol in vitro it was not evident in vivo. This may be due to compensating effects on neutrophil function during surgery in vivo. The decline in the neutrophil oxidative response in the local anaesthesia group might be due to increased stress and catecholamine concentrations or a direct interaction of local anaesthetics with neutrophil intracellular signalling.

Dose-dependent influence of barbiturates but not of propofol on human leukocyte phagocytosis of viable Staphylococcus aureus

OBJECTIVE

Deep sedation with barbiturates or propofol is a standard therapy for patients with critically elevated intracranial pressure. Such patients are prone to infectious complications, especially to pneumonias, which are most commonly caused by Staphylococcus aureus. Although various immunomodulatory effects of barbiturates have been described in vitro, their influence on the phagocytosis of viable S. aureus has yet to be investigated. Therefore, we examined the effects of thiopentone, methohexitone, and propofol on the phagocytosis of viable S. aureus.

DESIGN

Laboratory study.

SETTING

University laboratory.

PATIENTS

Ten healthy volunteers aged 32.5 +/- 7 yrs.

INTERVENTIONS

Blood sampling.

MEASUREMENTS AND MAIN RESULTS

Whole blood samples were preincubated with different concentrations of thiopentone, methohexitone, and propofol, which is an isopropylphenol derivate. After viable S. aureus was added, phagocytosis was stopped at different time points. Leukocytes were then stained with monoclonal antibodies for flow cytometric analysis of granulocyte recruitment (ratio of ingesting granulocytes) and phagocytosis activity (fluorescence intensity of ingested bacteria). Both barbiturates inhibited granulocyte recruitment and phagocytosis activity in a dose-dependent manner, whereas propofol did not affect any of the investigated variables. At concentrations higher than 7.6 x 10(-3) M (for thiopentone, p < .008) and 1.1 x 10(-3) M (for methohexitone, p < .04), granulocyte recruitment and phagocytosis activity were significantly inhibited. The calculated inhibitory concentrations (IC50) of thiopentone for granulocyte recruitment and for phagocytosis activity were 1.3 x 10(-2) M and 1.1 x 10(-2) M, respectively. The corresponding values for methohexitone were 3.6 x 10(-3) M and 1.1 x 10(-3) M.

CONCLUSIONS

Our in vitro model points at substantially different effects of barbiturates and propofol on phagocytosis of S. aureus, which is one of the most important pathogens in patients who need neuroprotective therapy. The inhibitory effects of both barbiturates demonstrate a strong dose-dependency, with more pronounced effects for methohexitone. Impairment of phagocytosis activity was more pronounced than granulocyte recruitment.

Influence of non-volatile anesthetics on the migration behavior of the human breast cancer cell line MDA-MB-468

BACKGROUND

Anesthetic agents are known to influence functions of the immune system. Anesthetic drugs also support cancer progression by suppressing the activity of immune cells. In breast carcinoma an increase in expression of peripheral-type benzodiazepine receptors (PBR) and the gamma aminobutyl acid (GABA) level has been discovered. Therefore, an investigation of a direct influence of GABA-A agonist propofol, GABA-A and PBR-agonist etomidate, and the local anesthetic drug lidocaine, which can also bind to the GABA-A receptor and PBR, on migration of breast carcinoma cells was performed.

METHODS

MDA-MB-468 cells were incubated with anesthetic agents using clinically relevant concentrations (propofol 3, 6, 9 mg/l, etomidate 2, 3, 4 mg/l, and lidocaine 1.25, 2.5, 5 mg/l). Locomotion was investigated in a three-dimensional collagen matrix using time-lapse video microscopy and computer-assisted cell-tracking.

RESULTS

The percentage of migrating cells (57.4+/-1.9) as well as the velocity (0.22+/-0.09 microm/min) and distance migrated (89.4+/-66.8 microm/10 h) increased in the presence of propofol in a dose-dependent manner (up to 74.4+/-7.5, 0.30+/-0.09, 143.8+/-89.1, respectively) compared with the long chain triglyceride (LCT) control. In contrast, no influence of etomidate on the number of migrating cells could be observed. The velocity and distance migrated at 3 and 4 mg/l were found to be statistically significantly enhanced. Treatment with lidocaine caused an increase in the percentage of migrating cells (up to 75.0+/-5.6) in velocity dose dependently (up to 0.33+/-0.06) and in distance migrated (up to 151.5+/-92.9).

CONCLUSION

These results show that different anesthetic drugs are able to modulate the migratory machinery of human breast carcinoma cells in vitro.