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The authors consider the issue of laptops and smartphones on the performance of an anaesthetist in the operating environment. The authors contend that there are limits to the ability of experienced and skilled anaesthetists in tackling distractions when using these computer and phone devices. For trainees with less experience, the authors recommend the discretionary use of laptops and smartphones in the operating theatre.

A recent report showed that morphine inhibited [3H]clonidine binding to human platelet alpha 2 receptors. As the analgesic effects of morphine and clonidine are clinically additive, we investigated the possibility that morphine might stimulate alpha 2 receptors or alpha 2 mechanisms in rat locus coeruleus (LC) slices. Stimulated LC noradrenaline efflux was measured by fast cyclic voltammetry. Cumulatively applied morphine 10(-8)-10(-4) mol litre-1 had no effect on noradrenaline efflux evoked by pseudo-single-pulse stimulations (20 pulses at 100 Hz) while the alpha 2 agonist dexmedetomidine 2 x 10(-10)-10(-7) mol litre-1 decreased efflux of noradrenaline in a concentration-dependent manner. Administration of single concentrations of morphine 10(-6)-10(-4) mol litre-1 significantly decreased efflux of noradrenaline (by 22% and 17%, respectively) and attenuated the effect of dexmedetomidine in a concentration-dependent fashion. Morphine 10(-6)-10(-4) mol litre-1 also decreased efflux of noradrenaline on long stimulus trains (50 pulses at 50 Hz). These data suggest that the analgesic potentiation of alpha 2 and opioid agonists is not mediated via LC alpha 2 receptors.

We have examined the effects of the highly selective alpha 2-adrenoceptor agonist, dexmedetomidine, on noradrenaline release and cell firing in isolated, superfused slices of rat locus coeruleus. Dexmedetomidine decreased both noradrenaline release and cell firing rate in a concentration-dependent fashion, with an EC50 of 3.97 (SEM 0.97) x 10(-9) mol litre-1 for noradrenaline release and 0.92 (0.53) x 10(-9) mol litre-1 for unit activity. Both effects were reversed completely by the selective alpha 2 antagonist, atipamezole 10(-6) mol litre-1. These results suggest that cell firing and noradrenaline release are under alpha 2 receptor control and that dexmedetomidine potently stimulates these receptors. We conclude that these effects are consistent with the locus coeruleus being a major site of action of the hypnotic anaesthetic alpha 2 agonists.