Propofol detection for monitoring of intravenous anaesthesia: a review

This paper presents a review of established and emerging methods for detecting and quantifying the intravenous anaesthetic propofol in solution. There is growing evidence of numerous advantages of total intravenous anaesthesia using propofol compared to conventional volatile-based anaesthesia, both in terms of patient outcomes and environmental impact. However, volatile-based anaesthesia still accounts for the vast majority of administered general anaesthetics, largely due to a lack of techniques for real-time monitoring of patient blood propofol concentration. Herein, propofol detection techniques that have been developed to date are reviewed alongside a discussion of remaining challenges.

The Efficacy of Prophylactic Intravenous Granisetron in Preventing Post Anaesthesia Shivering in Gynaecological Patients Undergoing Surgery Under General Anaesthesia

Post-anaesthetic shivering is one of the commonest complications during emergence from general anaesthesia with the rate of occurrence between 5 to 65%. It increases oxygen consumption and carbon dioxide production resulting in delayed recovery from anaesthesia and other adverse events. Granisetron is one of the drugs used to prevent post-anaesthetic shivering. This prospective, double-blind and randomised control study compared the efficacy of prophylaxis IV granisetron at 2 mg and 3 mg doses in preventing post-anaesthetic shivering. There were 104 patients, ASA I and II scheduled for elective open gynaecological surgery recruited and randomised into 2 groups: Group A and B, receiving 2 and 3 mg of IV granisetron, resepectively. Intravenous anaesthetic drugs were administered and tracheal intubation was facilitated by muscle paralysis. Patients’ baseline and periodic tympanic core temperatures were measured perioperatively. The incidence and severity of shivering were assessed postoperatively using Wrench Scoring Classification whereby Group A and B had 8.3% and 16.7% of incidence, respectively, in which they were not statistically significant (p = 0.199). All patients from both groups who shivered experienced Grade 1 shivering except for one patient who registered a Grade 2 in Group B. None of our patients had Grade 3 or 4 shivering postoperatively. No one experienced nausea or vomiting in the recovery area. Prophylactic IV granisetron of 2 mg and 3 mg were equally effective in reducing the incidence and severity of post-anaesthetic shivering in gynaecological patients undergoing surgery under general anaesthesia with no unpleasant side effects.

Neonatal administration of a subanaesthetic dose of JM-1232(−) in mice results in no behavioural deficits in adulthood

In animal models, neonatal exposure of general anaesthetics significantly increases apoptosis in the brain, resulting in persistent behavioural deficits later in adulthood. Consequently, there is growing concern about the use of general anaesthetics in obstetric and paediatric practice. JM-1232(−) has been developed as a novel intravenous anaesthetic, but the effects of JM-1232(−) on the developing brain are not understood. Here we show that neonatal administration of JM-1232(−) does not lead to detectable behavioural deficits in adulthood, contrarily to other widely-used intravenous anaesthetics. At postnatal day 6 (P6), mice were injected intraperitoneally with a sedative-equivalent dose of JM-1232(−), propofol, or midazolam. Western blot analysis of forebrain extracts using cleaved poly-(adenosine diphosphate-ribose) polymerase antibody showed that JM-1232(−) is accompanied by slight but measurable apoptosis 6 h after administration, but it was relatively small compared to those of propofol and midazolam. Behavioural studies were performed in adulthood, long after the neonatal anaesthesia, to evaluate the long-term effects on cognitive, social, and affective functions. P6 administration to JM-1232(−) was not accompanied by detectable long-term behavioural deficits in adulthood. However, animals receiving propofol or midazolam had impaired social and/or cognitive functions. These data suggest that JM-1232(−) has prospects for use in obstetric and paediatric practice.

Anaesthesia

This chapter in the Oxford Handbook of Clinical Specialties explores the specialty of anaesthesia. It reviews preoperative assessment, sedation, drugs used to induce anaesthesia, inhalational anaesthetic agents, intravenous anaesthetic agents, and muscle relaxants. It explores the practical conduct of anaesthesia, Difficult Airway Society (DAS) guidelines, maintaining and monitoring, rapid sequence induction aspiration, and intubation technique. It examines some complications of anaesthesia, end of anaesthesia, recovery, pain, and postoperative nausea and vomiting, and describes regional anaesthesia, including peripheral nerve blocks and neuraxial anaesthesia.

Propofol promotes apoptosis of colorectal cancer cells via alleviating the suppression of lncRNA HOXA11-AS on miRNA let-7i

To date, surgical resection is the mainstay for the treatment of colorectal cancer (CRC). Propofol (2,6-diisopropylphenol), one of the most commonly used intravenous anaesthetic agents, has been reported to be involved in modulating the malignancy of a variety of human cancers. However, the underlying mechanisms remain poorly understood. In this study, using a cell counting kit (CCK-8), flow cytometry, and caspase-3 cleavage assays, we found that propofol promoted cell apoptosis and inhibited cell proliferation in both Colo205 and SW620 cells, through the down-regulation of HOXA11-AS and up-regulation of let-7i. Moreover, gain-of-function studies of HOXA11-AS or loss-of-function studies of let-7i also revealed a negative correlation between HOXA11-AS and let-7i in propofol-mediated biological functions of CRC cells. Furthermore, our mechanistic experiments revealed that HOXA11-AS acts as a molecular sponge for let-7i, thereby regulating the expression of ABCC10. We investigate the theory that propofol suppresses colorectal cancer tumorigenesis by modulating the HOXA11-AS–let-7i–ABCC10 regulatory network, indicating the potential for propofol to control CRC development.

Metoclopramide Pretreatment for Prevention of Pain on Propofol Injection: A Randomized Placebo-Controlled Study

Background: Propofol, the most frequently used intravenous anaesthetic, is used for induction, maintenance of anaesthesia and for sedation in patients scheduled for routine elective surgical procedure. Pain on propofol injection still remains a considerable concern for the anaesthesiologist. Objective: Aim of this study was to observe the efficacy of metoclopramide as pretreatment for the prevention of pain caused by the propofol injection in patients undergoing elective surgery under general anaesthesia. Materials and method: A total of 80 patients were taken up in the study in the age group of 20 to 50 years of either sex, ASA grade I/II, scheduled for routine elective surgical procedure under general anesthesia with endotracheal intubation and using propofol as induction agent. The patients enrolled were divided randomly into two groups of 40 patients each. Group A received 10 mg metoclopramide IV diluted in 5 ml saline. Group B received 5 ml of normal saline as placebo before propofol injection. The patients were asked to report their pain according to the scale provided to them in the form of none, mild, moderate and severe after injection of propofol. Results: The overall incidence and severity of pain were significantly less in Group A (metoclopramide group) than in group B (placebo group) (p< 0.05). The incidence of mild and moderate pain in Group A versus group B was 15% vs 45% and 5% vs 25% respectively (p<0.05). The incidence of score ‘0’ (no pain) was higher in Group A (80%) thanGroup B (25%) (p< 0.05). Conclusion: Intravenous metoclopramide is effective for relief of pain on propofol injection without any significant side effects. Delta Med Col J. Jul 2019 7(2): 71-75

Pharmacology and fluids

Differences in pharmacokinetics and pharmacodynamics are important in small children. This chapter provides an overview of essential pharmacokinetic parameters and developmental aspects. Intravenous anaesthetic agents, including total intravenous anaesthesia models, are described. An overview of commonly used inhalational anaesthetic agents, sedatives, and neuromuscular blockers is given. The analgesic sections describe opioids, simple analgesics, and local anaesthetic agents. Paediatric indications, common side effects, and dosing are included for each agent. A fundamental understanding of developmental differences is key to the safe and effective use of anaesthetic drugs in children.

Effect of 2,6-diisopropylphenol and 1,1,1,3,3,3-hexafluoro-2-(fluoromethoxy) propane as Anesthetic

Sevoflurane (2,2,2-trifluoro-1-[trifluoromethyl]ethyl fluoromethyl ether or C4H3F7O), with a molar mass 200.055 g/mol, also called fluoromethyl, is a highly fluorinated methyl isopropyl ether with general anesthetic property, available for clinical practice for about 30 years. Sevoflurane is a sweet-smelling, non-flammable and it is used for induction and maintenance of general anesthesia. Together with desflurane, it is replacing isoflurane and halothane in modern anesthesiology. Propofol (2,6-diisopropylphenol or C12H18O), with a molar mass 178.271g/mol is an alkylphenol derivative formulated for induction and maintenance (in some cases) of general anesthesia, sedation and hypnosis and acting as an intravenous anaesthetic drug, having largely replaced sodium thiopental because recovery from propofol is more rapid and clear.

Propofol Induces Postoperative Depression and Inhibits Microglial Function in Mice

Many patients experience excellent physical recoveries after surgery; however, there are some of them who from suffer mood fluctuation, even depression. Postoperative depression may be resulted from cognitive dysfunction, pain, and a compromised immune system during the surgery. But there is a higher possibility that general anaesthesia may be responsible for the development of depression. Here, we employed one of the most used anaesthetics, propofol, in a mouse model to investigate whether this intravenous anaesthetic compound could cause depressive-like behavioural performance in mice. We found a single dose of propofol caused significant abnormal behavioural performance in tail suspension, forced swimming, and open field tests. We also examined the brain section of these mice and revealed that there was significant reduced expression of the CD11b protein, which demonstrated an inhibition of propofol on microglial function. We investigated the effect of propofol on synaptic protein, SYP, and found there was no notable influence on the protein expression. These above results suggested that propofol treatment might promote the depressive-like behaviours in mice via influencing the microglial cell function. Furthermore, we found the level of the IL-6 cytokine was significantly increased in the brain tissue, which might subsequently cause the activation of the transcriptional factor, STAT3. Our finding may provide a new perspective of further understanding the mechanism of anaesthetic drugs and deciphering the underlying mechanism of postoperative depression.