Erectile dysfunction and sildenafil.

The ability of pharmacists to identify potential drug interactions was studied. Simulated medication profiles were created from a list of 16 drugs. Staff pharmacists and soon-to-graduate student pharmacists at a Veterans Affairs medical center each received a set of eight 2-drug profiles, four 4-drug profiles, two 8-drug profiles, and one 16-drug profile. Each set of profiles contained a number of pairs of drugs rated by the Drug Therapy Screening System as producing an interaction of moderate or major importance. The subjects were given one hour to screen the profile for the potentially interacting pairs. The subjects detected only 66% of the interactions in the 2-drug profiles, 34% of the interactions in the 4-drug profiles, 20% of the interactions in the 8-drug profiles, and 17% of the interactions in the 16-drug profile. None of the subjects detected all interactions in the 8- or 16-drug profiles. Both true-positive and false-positive rates of identification decreased significantly as the number of drugs listed on the profile increased. This primarily reflected a reduced tendency to report the presence of drug interactions, but there was additional evidence that the accuracy of identification also declined. The number of years of pharmacy training was the only demographic characteristic highly correlated with accuracy. More years of pharmacy education seemed to improve the ability to detect drug interactions. However, none of the pharmacists or students was able to detect all potentially interacting pairs in a profile containing 8 or 16 drugs. Computerized drug interaction profiles should be used by pharmacists to ensure recognition of all potential drug interactions.

Drug Interactions↗

PubMed1999

Monitoring and reversal of neuromuscular block.

Methods of monitoring and reversing neuromuscular blocking agents to avoid residual neuromuscular block are described. Studies have shown that if a long-acting neuromuscular blocking agent is used during anesthesia, the frequency of residual block, regardless of the method of neuromuscular monitoring, will be at least 20%. In the past 20-25 years, anesthesiologists have come to use some form of nerve stimulation to monitor the degree of residual neuromuscular block; there are various patterns of stimulation, including train-of-four (TOF) stimulation and double-burst stimulation (DBS). For both TOF stimulation and DBS, the response to the stimuli in a series fades such that the last response can be expressed as a ratio of the first. The fade to DBS is the same as that to TOF stimulation. Clinicians can clinically detect a fade in TOF response when the TOF ratio is <0.5. Fade to DBS is easier to detect than that to TOF stimulation, but, as the block recovers, the anesthesiologist's ability to detect fade decreases. Although anesthesiologists have accepted a TOF ratio of at least 0.7 as the standard, studies of vecuronium neuromuscular block have shown an impaired ventilatory response to hypoxemia and the possibility of increased risk of aspiration until the TOF ratio recovered to 0.9. The use of pancuronium and a persistent TOF ratio of 0.7 in the postanesthesia care unit was shown to be associated with a threefold greater occurrence of postoperative pulmonary complications compared with vecuronium or atracurium. Spontaneous recovery from neuromuscular block occurs through redistribution, metabolism, or buffered diffusion, but recovery can be accelerated by administration of anticholinesterase agents, such as neostigmine and edrophonium. Studies suggest that even intermediate-duration agents should be reversed. Rapacuronium is a new investigational drug with similar onset characteristics to succinylcholine and, if reversed early, similar recovery characteristics. Postoperative residual neuromuscular block is frequent, dangerous, and difficult to recognize clinically. The action of neuromuscular blocking agents should always be reversed unless there is unequivocal evidence of adequate function.

Drug Interactions↗