The choice of anaesthetic may influence regulation of renal perfusion and function. We investigated renal function in patients anaesthetised with propofol or sevoflurane before surgery and postoperatively. Patients with ASA physical status 1-2 planned for spinal surgery were randomised to propofol or sevoflurane anaesthesia. Blood and urine were collected before anaesthesia, during anaesthesia (before surgery), during postoperative care, and the day after surgery. Twenty-seven patients completed the study protocol (average age, 51 yr; average BMI, 28 kg m^-2) and 11 were women. Urine output and sodium excretion were lower during sevoflurane anaesthesia (n=14) than during propofol anaesthesia (n=13) (0.3 vs 1.1 ml kg^-1 h^-1 [P=0.01] and 2.6 vs 6.0 mmol h^-1 [P=0.04], respectively). Urinary potassium excretion was lower during anaesthesia than after, without intergroup difference (2.3 vs 5.7 mmol h^-1, P<0.001). Sevoflurane anaesthesia increased plasma renin compared with baseline (138 vs 23 mIU L^-1, P<0.001) and propofol anaesthesia (138 vs 27 mIU L^-1, P=0.008). Plasma arginine-vasopressin did not change significantly during anaesthesia, but was elevated postoperatively compared with baseline irrespective of anaesthetic (21 vs 12 ng L^-1, P=0.02). Sevoflurane caused higher postoperative plasma creatinine than propofol (83 vs 66 mmol L^-1, P=0.01). Kidney injury molecule-1 and neutrophil gelatinase-associated lipocalin did not change significantly in either group. Sevoflurane anaesthesia reduced urine output and sodium excretion and increased plasma renin compared with propofol anaesthesia. The impact of this on acute kidney injury and fluid resuscitation during surgery warrants further investigation. EudraCT: 2017-001646-10; Clinicaltrials.gov: NCT0333680.

Approximately 7% of patients undergoing non-cardiac surgery with general anesthesia develop postoperative acute kidney injury (AKI). It is well-known that general anesthesia may have an impact on renal function and water balance regulation, but the mechanisms and potential differences between anesthetics are not yet completely clear. Recently published large animal studies have demonstrated that volatile (gas) anesthesia stimulates the renal sympathetic nervous system more than intravenous propofol anesthesia, resulting in decreased water and sodium excretion and reduced renal perfusion and oxygenation. Whether this is the case also in humans remains to be clarified. Increased renal sympathetic nerve activity may impair renal excretory function and oxygenation and induce structural injury in ischemic AKI models and could therefore be a contributing factor to AKI in the perioperative setting. This review summarizes anesthetic agents' effects on the renal sympathetic nervous system that may be important in the pathogenesis of perioperative AKI.

This study analyzed the available literature on anesthetic modality and incidence of postoperative AKI. The meta-analysis revealed that propofol is associated with lower incidence of AKI compared with volatile anesthesia. It might therefore be considerable to use propofol anesthesia in surgeries with increased susceptibility for developing renal injuries such as cardiopulmonary bypass and major abdominal surgery.

We studied the function of renal cortical mitochondria in relation to oxygen consumption in an ovine model of sepsis with acute kidney injury. We demonstrated changes in the electron transport chain induced by sepsis consisting of a reduced respiratory control ratio mainly by a reduced complex I-mediated respiration. Neither an increase in mitochondrial uncoupling nor a reduction in mitochondrial efficiency was demonstrated and cannot explain why oxygen consumption was unaffected despite reduced tubular transport.

Dexamethasone (Dex) has been shown to decrease mortality in severe coronavirus disease 2019 (COVID-19), but the mechanism is not fully elucidated. We aimed to investigate the physiological and immunological effects associated with Dex administration in patients admitted to intensive care with severe COVID-19. A total of 216 adult COVID-19 patients were included—102 (47%) received Dex, 6 mg/day for 10 days, and 114 (53%) did not. Standard laboratory parameters, plasma expression of cytokines, endothelial markers, immunoglobulin (Ig) IgA, IgM, and IgG against SARS-CoV-2 were analyzed post-admission to intensive care. Patients treated with Dex had higher blood glucose but lower blood lactate, plasma cortisol, IgA, IgM, IgG, D-dimer, cytokines, syndecan-1, and E-selectin and received less organ support than those who did not receive Dex (Without-Dex). There was an association between Dex treatment and IL-17A, macrophage inflammatory protein 1 alpha, syndecan-1 as well as E-selectin in predicting 30-day mortality. Among a subgroup of patients who received Dex early, within 14 days of COVID-19 debut, the adjusted mortality risk was 0.4 (95% CI 0.2–0.8), i.e., 40% compared with Without-Dex. Dex administration in a cohort of critically ill COVID-19 patients resulted in altered immunological and physiologic responses, some of which were associated with mortality.

Surgical tissue trauma stimulates an inflammatory response resulting in increased levels of cytokines which could contribute to acute kidney injury (AKI). It is not clear if anesthetic modality affects this response. We aimed to investigate the role of anesthesia in a healthy surgical population on the inflammatory response and the correlation to plasma creatinine. This study is a post hoc analysis of a published randomized clinical trial. We analyzed plasma from patients who underwent elective spinal surgery randomized to either total intravenous propofol anesthesia (n = 12) or sevoflurane anesthesia (n = 10). The plasma samples were collected before anesthesia, during anesthesia, and 1 h after surgery. Plasma cytokine levels after surgery were analyzed for correlations with duration of surgical insult and change in plasma creatinine concentration. The cytokine interleukin-6 (IL-6) was increased after surgery compared with preoperatively. IL-6 was higher in the sevoflurane group than the propofol group after surgery. No patient developed AKI, but plasma creatinine was increased postoperatively in the sevoflurane group. There was a significant association between surgical time and plasma IL-6 postoperatively. No significant correlation between change in plasma creatinine and IL-6 was detected. The cytokines IL-4, IL-13, Eotaxin, Interferon γ-Induced Protein 10 (IP-10), Granulocyte Colony-Stimulating Factor (G-CSF), Macrophage Inflammatory Protein-1β (MIP-1β), and Monocyte Chemoattractant Protein 1 (MCP-1) were lower postoperatively than before surgery independent of anesthetic modality. This post hoc analysis revealed that plasma IL-6 was increased after surgery and more so in the sevoflurane group than the propofol group. Postoperative plasma IL-6 concentration was associated with surgical time.