The blood–gas partition coefficient

A partition coefficient (λ) describes the relative affinity of a volatile anaesthetic for two phases and how that anaesthetic distributes itself between the two phases when equilibrium has been achieved. The blood–gas partition coefficient (λb/g), or Ostwald coefficient for blood–gas, is a pharmacological term used to describe the solubility of a volatile anaesthetic agent. Volatile agents with a low blood–gas partition coefficient (less soluble) will exert a high partial pressure and produce a more rapid onset and offset of anaesthetic action.

Chloroform alters interleaflet coupling in lipid bilayers: an entropic mechanism

The interaction of the two leaflets of the plasmatic cell membrane is conjectured to play an important role in many cell processes. Experimental and computational studies have investigated the mechanisms that modulate the interaction between the two membrane leaflets. Here, by means of coarse-grained molecular dynamics simulations, we show that the addition of a small and polar compound such as chloroform alters interleaflet coupling by promoting domain registration. This is interpreted in terms of an entropic gain that would favour frequent chloroform commuting between the two leaflets. The implication of this effect is discussed in relation to the general anaesthetic action.

Purulent Trunk Dermatitis in a Male Ceylon Elephant (Elephas maximus maximus)

The study describes the therapy of purulent trunk dermatitis in an aggressive male Ceylon elephant (Elephas maximus maximus). The elephant was immobilized 4 times with 1.7 ml Large Animal (LA) Immobilon i.m. within 50 days. The anaesthetic action was antagonised with 1.7 ml LA Revivon + 8.0 ml Naloxone i.v. and 0.5 ml LA Revivon + 6.0 ml Naloxone i.m. From skin lesions the following pathogens were isolated: Staphylococcus spp., Streptococcus spp. and Candida tropicalis. Local therapy consisted of the debridement of the affected skin, application of antibiotics and skin antiseptics. Depot penicillin, vitamins, probiotics and autogenous yeast vaccine were administered generally. In haematological indicators the biggest changes were found in the numbers of white blood cells and segmented neutrophils. Markedly low zinc concentrations were found repeatedly. Despite the non-standard steps we took (repeated anaesthesia during a short time, non-compliance with the recommendations for the administration of some drugs, etc.) and difficult handling (aggressive, uncontrollable elephant, no restraint chute), it proved possible to treat such a case in this manner.