Increased dietary protein-to-lipid ratio improves survival during naturally occurring pancreas disease in Atlantic salmon, Salmo salar L

This study demonstrated that increased dietary protein-to-lipid ratio (P/L-ratio) improved survival of farmed Atlantic salmon naturally affected by pancreas disease (PD). In addition to diet, body weight (BW) and delousing mortality prior to the PD outbreak also contributed significantly (p < 0.05) to explain the observed variation in PD-associated mortality. Subsequent to the PD outbreak, large amount of fish failed to grow and caused thin fish with poor condition (runts). At the end of the trial, significantly (p < 0.05) lower amounts of runt fish and increased amount of superior graded fish where detected among fish fed increased P/L-ratio and within the fish with the largest BWs prior to PD. Diet, BW and delousing mortality contributed significantly (p < 0.05) to explain the variation in the amount of superior graded fish, whereas BW and diet explained the variation in the amount of runt fish. A significant (p < 0.01) negative linear relationship was observed between the amount of superior graded fish and the total mortality, whereas a positive linear relationship was detected between percentage of fillets with melanin and the total mortality. Thus, increased dietary P/L-ratio seem to reduce the mortality and impaired slaughter quality associated with PD.

Duration of vecuronium-induced neuromuscular blockade predicted by dose and onset time

We investigated the adequacy of using dose and onset time as variables to predict the duration of action of vecuronium in patients. The onset time until 95% twitch depression and the duration until 25% twitch recovery were measured for doses ranging from 0.1 to 0.3 mg kg-1. Statistical analyses were performed by simple and multiple regressions. The duration of action was better predicted by dose (r2 = 0.61) than by onset time (r2 = 0.51). However, the predictability was significantly improved by a multiple regression model of the variables, and the explanatory power was largest when using the square root of duration as the dependent variable (r2 = 0.69). We conclude that the duration of neuromuscular blockade after vecuronium can be predicted more accurately by the combined use of dose and onset time than by dose alone.

Midazolam does not potentiate the effect of vecuronium in patients

Reports of midazolam interaction with vecuronium in animals prompted us to compare midazolam (0.25 mg kg-1) with thiopentone (5 mg kg-1) for possible interactions with vecuronium in patients, when used for induction of anaesthesia. After the administration of either of the two induction agents, the patients received vecuronium 0.1 mg kg-1. The onset time, duration of action and 25-75% recovery index of the neuromuscular blockade were recorded by measuring the force of thumb adduction evoked by ulnar nerve stimulation. We found no differences between patients receiving either midazolam or thiopentone in their response to vecuronium. In three of the ten patients receiving midazolam, the injection of this drug produced a 8-29% reduction of the initial twitch height.

Comparison of large dose of vecuronium with pancuronium for prolonged neuromuscular blockade

Dose-duration relationships for vecuronium were determined and the duration of action produced by vecuronium 0.3 mg kg-1 shown to equal that of pancuronium 0.1 mg kg-1. Using these doses, the neuromuscular blocking properties and cardiovascular effects of the two drugs were compared. With large dose administration of vecuronium (0.3 mg kg-1), both the onset time (mean 81 s) and the 25-75% recovery index (mean 13.9 min) were about one-half those associated with pancuronium (mean 168.5 s and 29.3 min, respectively). The duration of action until 25% recovery was similar with both drugs. There was no evidence of cardiovascular instability with the large dose of vecuronium. Heart rate, however, was significantly slower (range 89.7-94.2% of control) 2-20 min after the injection of vecuronium. Vecuronium 0.3 mg kg-1 may have more favourable neuromuscular blocking effects than pancuronium 0.1 mg kg-1 and may be preferable to pancuronium when prolonged neuromuscular blockade is required.