Fatal methylene blue associated serotonin toxicity.

This is the first report of a fatal outcome from serotonin toxicity, precipitated by an interaction between methylene blue and venlafaxine. Methylene blue-associated serotonin toxicity has been described before but usually as mild toxicity. Its presentation after general anaesthesia may be atypical and therefore more difficult to diagnose. However, the syndrome is completely preventable if serotonin re-uptake inhibiting agents are stopped beforehand.

Workload and main activities of consultative ICU nurses: long-term experience in a large teaching hospital in the Netherlands.

BACKGROUND: Early recognition and prompt treatment of deteriorating patients outside the intensive care unit (ICU) improves hospital survival. Over the past decade, consultative services have been implemented in many institutions. This service is frequently performed by ICU nurses, while little information is available on the workload and type of activities these ICU nurses actually perform. METHODS: In 1995, a consultative ICU nurse-driven service was introduced in a large teaching hospital in the Netherlands. In this descriptive study, we determined types of consultation, time consumed per visit, and main interventions during these activities. RESULTS: During the study period, 9144 consultations in 4365 patients were performed. While the number of 'scheduled' visits (visits of patients after discharge from the ICU) was reasonably variable during the study period, the number of 'on demand' visits (visits demanded by non-ICU personnel) increased gradually, especially during the first years. At the end of the observation period, approximately half of the visits were 'on demand' in the non-ICU wards. The mean number of consultations per patient dropped gradually over the whole period, from 4.02 in 1996 to 1.54 in 2004. The total workload was approximately half an hour per day; visits were combined with regular activities of the ICU team. Tracheal suctioning was among the most frequent activities during consultation (approximately 90% of all visits). CONCLUSION: Consultative ICU nurses play a growing role in bridging the gap between the ICU and non-ICU departments in our hospital. Workload is acceptable.

The effect of single twitch and train-of-four stimulation on twitch forces during stable neuromuscular block.

OBJECTIVE: We investigated whether the response to a single twitch (ST) stimulus or the first response (T1) to a train-of-four (TOF; 4 stimuli at 2 Hz) stimulus following a stimulus interval of 10 s (i.e., the time between two consecutive ST or TOF stimuli) is influenced by the preceding stimulus in the presence of a stable 50% neuromuscular block. In addition, we determined whether ST and TOF stimulation yield different results under these circumstances. METHODS: Twitch forces were measured in both tibialis anterior muscles of six cats. In the presence of a stable 50% neuromuscular block the stimulation pattern (ST or TOF) or stimulus interval (3.3, 10 or 30 s) was varied every 30 min. A linear mixed model was used for statistical analysis. RESULTS: ST forces with a stimulus interval of 3.3 s were 10.3% (95% CI: 7.3-13.3%) smaller than those with a stimulus interval of 10 s. For T1 forces this effect was 15.2% (95% CI: 12-18.4%). There was no significant difference between twitch forces with stimulus intervals of 30 and 10 s. For a stimulus interval of 3.3 s the ST forces exceeded the T1 forces by 7.6% (95% CI: 4.4-10.8%); no significant differences were found between the ST and T1 forces for stimulus intervals of 10 and 30 s. CONCLUSIONS: The ST or T1 force during stimulation with a stimulus interval of 10 s or more during a stable 50% neuromuscular block in the tibialis anterior muscle of the cat is not affected by the preceding stimulus. In addition, ST and T1 forces do not differ when employing a stimulus interval of 10 s or more under these circumstances. Our results thus indicate that the known differences between ST and T1 forces after a bolus injection of a muscle relaxant can not be explained by differences in acetylcholine release when the stimulus interval exceeds 10 s.