isoflurane

Isoflurane

Can produce isoelectric EEG without metabolic toxicity. Improves neurologic outcome in cases of incomplete global ischemia (although in experimental studies on rats, the amount of tissue injury was greater than with thiopental).


Shorter acting and less myocardial depression than with barbiturates


Isoflurane is a safe and reliable anesthetic gas with a long history of clinical application. In recent years, its protection function to the human body has been widely recognized, and nowadays isoflurane for cerebral protection has been widely studied, and the stable effect of isoflurane has satisfied many researchers. Basic studies have shown that isoflurane's protection of brain tissue after ischemia/reperfusion involves a variety of signaling pathways and effector molecules. Even though many signaling pathways have been described, more and more studies focus on exploring their mechanisms of action, in order to provide strong evidence for clinical application. This could prompt the introduction of isoflurane therapy to clinical patients as soon as possible 1).


Isoflurane enhances BBB permeability in a time- and concentration-dependent manner. We demonstrate that, mechanistically, isoflurane disturbs the organization of membrane lipid nanodomains and triggers caveolar transport in brain endothelial cells. BBB tightness re-establishes directly after the termination of anesthesia, providing a defined window for drug delivery. In a therapeutic glioblastoma trial in mice, simultaneous exposure to isoflurane and cytotoxic agent improves the efficacy of chemotherapy.

Combination therapy, involving isoflurane-mediated BBB permeation with drug administration has far-reaching therapeutic implications for CNS malignancies 2).


This study was carried out to compare the cerebral and systemic circulatory effect of halothane and isoflurane. Six mongrel dogs were anesthetized with 1.3 minimal alveolar concentration (MAC) (1%) halothane and were compared with six mongrel dogs anesthetized with 1.3 MAC (1.5%) isoflurane. Likewise, 6 dogs anesthetized with 1.7 MAC (1.3%) halothane were compared with 6 dogs anesthetized with 1.7 MAC (2%) isoflurane. Blood flow (using the radioactive microsphere technique) and cardiovascular measurements were obtained 2 hours after the induction of anesthesia and were repeated 5 more times at hourly intervals. The heart rate was similar in all groups of dogs, except that it was significantly lower with 1.7 MAC halothane. The mean arterial pressure was statistically higher with isoflurane at both concentrations than with halothane. The cardiac index was similar in all groups, except with 1.7 MAC isoflurane, when it was higher. At the early measurements, total cerebral blood flow (CBF) was above “normal” levels in all groups. At 1.3 MAC, the total CBF tended to be lower with isoflurane, but did not reach statistically significant levels. Blood flow decreased over time in all groups. The cerebral vascular resistance (CVR) mirrored the changes in blood flow, showing no difference between agents at 1.7 MAC, but the CVR with isoflurane was significantly higher at 1.3 MAC than it was with halothane. Regional cerebral blood flow showed marked differences. Regional flow to the hemispheres and the cortical gray matter showed that isoflurane tended to produce lower blood flow, particularly at the 1.3 MAC concentration. The reverse was true in the posterior fossa structures, with the brain stem and cerebellum showing higher blood flows with isoflurane, particularly at 1.7 MAC. Isoflurane may have several advantages over halothane for neurosurgical procedures 3).


1)
Chen SJ, Yuan XQ, Xue Q, Lu HF, Chen G. Current research progress of isoflurane in cerebral ischemia/reperfusion injury: a narrative review. Med Gas Res. 2022 Jul-Sep;12(3):73-76. doi: 10.4103/2045-9912.330689. PMID: 34854416.
2)
Spieth L, Berghoff SA, Stumpf SK, Winchenbach J, Michaelis T, Watanabe T, Gerndt N, Düking T, Hofer S, Ruhwedel T, Shaib AH, Willig K, Kronenberg K, Karst U, Frahm J, Rhee JS, Minguet S, Möbius W, Kruse N, von der Brelie C, Michels P, Stadelmann C, Hülper P, Saher G. Anesthesia triggers drug delivery to experimental glioma in mice by hijacking caveolar transport. Neurooncol Adv. 2021 Sep 20;3(1):vdab140. doi: 10.1093/noajnl/vdab140. PMID: 34647026; PMCID: PMC8500692.
3)
Boarini DJ, Kassell NF, Coester HC, Butler M, Sokoll MD. Comparison of systemic and cerebrovascular effects of isoflurane and halothane. Neurosurgery. 1984 Sep;15(3):400-9. PubMed PMID: 6483155.
  • isoflurane.txt
  • Last modified: 2021/12/02 23:49
  • by administrador