Dive history may eliminate decompression sickness in many cases, and the presence of symptoms of other lung overexpansion injury would raise the probability of gas embolism. Treatment
A large bubble of air in the heart (as can follow certain traumas in which air freely gains access to large veins) will present with a constant "machinery" murmur. It is important to promptly place the patient in Trendelenburg position (head down) and on their left side (left lateral decubitus position). The Trendelendburg position keeps a left-ventricular air bubble away from the coronary artery ostia (which are near the aortic valve) so that air bubbles do not enter and occlude the coronary arteries (which would cause a heart attack). Left lateral decubitus positioning helps to trap air in the non-dependent segment of the right ventricle (where it is more likely to remain instead of progressing into the pulmonary artery and occluding it). The left lateral decubitus position also prevents the air from passing through a potentially patent foramen ovale (present in as many as 30% of adults) and entering the left ventricle, from which it could then embolise to distal arteries (potentially causing occlusive symptoms such as stroke).Administration of high percentage oxygen is recommended for both venous and arterial air embolism.
The seven confirmed cases were all older than 60 and symptoms appeared within two weeks of initiation of therapy. Pharmacology
Mechanism of action
Daptomycin has a distinct mechanism of action, disrupting multiple aspects of bacterial cell membrane function. It inserts into the cell membrane in a phosphatidylglycerol-dependent fashion, where it then aggregates. The aggregation of daptomycin alters the curvature of the membrane, which creates holes that leak ions. This causes rapid depolarization, resulting in a loss of membrane potential leading to inhibition of protein, DNA, and RNA synthesis, which results in bacterial cell death.It has been proposed that the formation of spherical micelles by daptomycin may affect the mode of action. Microbiology
Daptomycin is bactericidal against Gram-positive bacteria only. It has proven in vitro activity against enterococci (including glycopeptide-resistant enterococci (GRE)), staphylococci (including methicillin-resistant Staphylococcus aureus), streptococci, corynebacteria and stationary-phase Borrelia burgdorferi persisters. Daptomycin resistance
Daptomycin resistance is still uncommon, but has been increasingly reported in GRE, starting in Korea in 2005, in Europe in 2010, in Taiwan 2011, and in the United States, where nine cases have been reported from 2007 to 2011. Daptomycin resistance emerged in five of the six cases while they were treated. The mechanism of resistance is unknown. A four-million year-old strain of Paenibacillus isolated from soil samples in Lechuguilla Cave was found to be naturally resistant to daptomycin. Efficacy
Daptomycin has been shown to be non-inferior to standard therapies (nafcillin, oxacillin, flucloxacillin or vancomycin) in the treatment of bacteraemia and right-sided endocarditis caused by S. aureus.