Adsorbent comparisons for anesthetic gas capture in hospital air emissions

For the development of emission control strategies, activated carbon, zeolite, molecular sieves, and a silica gel were tested for adsorption of the newer anesthetic gases isoflurane, sevoflurane, and desflurane from air. The activated carbon Norit GCA 48 was selected for the best performance, and adsorption isotherms at room temperature were developed for the three anesthetics. Equilibrium capacities for this carbon were in the range of 500 to 1,000 mg g(-1) for these anesthetics at partial pressures ranging from 5 to 45 Torr, with the most volatile compound (desflurane) showing the least favorable adsorption. Activated carbons are therefore suggested for use as effective adsorbents in emission control of these anesthetic gases from hospitals.

[Not Available]

This new paper on chemical risk from anaesthetic agents in operating theatres is the natural progression of that published in this journal in supplement 1-2013, as it constitutes a development and complement of the previous work and an applicative confirmation from the highest organ of administrative justice, the Consiglio di Stato, regarding, in particular, the obligation of adopting the technically most advanced "measures" to eliminate or, at least, minimise risk in the use of new generation and the most commonly-used anaesthetic agents (sevoflurane and desflurane). Therefore, in this paper, the authors commence by referring to the starting point, consisting in the conclusions of the previous study, which highlighted the extraordinary convergence of technical and scientific, legislative and case law data on the same result, constituted by the possibility, and consequent obligation, of implementing, also in operating theatres, the greatest technologically possible safety, starting with the choice of the most suitable equipment, methods and quality systems for avoiding the diffusion, dispersion and /or leakage of volatile hazardous agents that may contribute - together with those chemical reactions that are foreseeable and avoidable, given the characteristics of the materials, substances and relative "packaging" - to workplace pollution, which can, in any case, reach levels that are hazardous due to the concentration of anaesthetic gases. Subsequently, once the "scientific" fruit of the previous contributions has been discussed, the authors evaluate the impact of the result already achieved in practice with concrete cases and the judgement expressed with a series of judgements issued in rapid succession by the Consiglio di Stato, showing the application, not merely of the legislative "data" but also of the references and citations that these "data" contain regarding the "knowledge acquired regarding the relationship with technical progress". Lastly, the Authors provide, as a further, definitive conclusion, the singular unit of the guidelines provided by case law, the result of a univocal and continuous multitude of judgements issued at the highest degree of administrative justice, albeit for very diverse situations and circumstances, which provide, therefore, a direction and an operative guide for which they are called on to adopt roles and responsibilities for the choices of "products", "systems" and "methods" destined to affect - for the use of anaesthetic agents - the health and safety of healthcare staff and of patients themselves.

Comparative evaluation of propofol, sevoflurane and desflurane for neuroanaesthesia: A prospective randomised study in patients undergoing elective supratentorial craniotomy

Background and Aims:

Both inhalational and intravenous anaesthetic agents are being used for neuroanaesthesia. Clinical trials comparing “propofol and sevoflurane” and “desflurane and sevoflurane” have been published. However, the comparison of all the three anaesthetics in neurosurgical patients has not been done. A randomised clinical study was carried out comparing propofol, sevoflurane and desflurane to find the ideal neuroanaesthetic agent.

Methods:

A total of 75 adult patients undergoing elective craniotomy for supratentorial tumours were included in the study. The patients were induced with morphine 0.1 mg/kg and thiopentone 4-6 mg/kg. Neuromuscular blockade was facilitated with vecuronium. The patients were randomised to receive propofol, sevoflurane or desflurane along with nitrous oxide in oxygen for maintenance of anaesthesia. The neuromuscular blockade was reversed following the surgery once the patients opened eyes or responded to verbal commands. The three anaesthetics were compared for their effects on haemodynamics, brain relaxation and emergence characteristics.

Results:

The mean arterial blood pressure during anaesthesia was comparable among the groups. The patients receiving sevoflurane had faster heart rates intraoperatively when compared to desflurane (P < 0.05). The brain relaxation scores at various intraoperative time frames were comparable among the three groups (P > 0.05). The time to response to verbal commands were significantly prolonged with use of sevoflurane (8.0 ± 2.9 min) when compared to propofol (5.3 ± 2.9 min) and desflurane (5.2 ± 2.6 min) (P = 0.003). However, the time to emergence and the number of patients who had early emergence (<15 min) were comparable among the groups (P > 0.05). The quality of emergence (coughing and emergence agitation), as well as postoperative complications, were also comparable among the three groups.

Conclusions:

All the three anaesthetic agents-propofol, sevoflurane and desflurane appear comparable and acceptable with regard to their clinical profile during anaesthesia in patients undergoing elective supratentorial surgeries.