Sleep, Caffeine Use May Play Role in Post-Op Pain
Caffeine at onset of sleep deprivation might help prevent increase in post-op hypersensitivity
WEDNESDAY, Aug. 23, 2017 (HealthDay News) -- Extended wakefulness prior to surgery significantly enhances postoperative pain behaviors and extends recovery time after surgery, but caffeine may help mitigate this effect, according to an experimental study published online Aug. 3 in SLEEP.
Viviane S. Hambrecht-Wiedbusch, Ph.D., from the University of Michigan in Ann Arbor, and colleagues used a rat model of surgical pain to examine the effect of previous sleep loss on postoperative pain, and explored whether preoptic adenosinergic mechanisms regulate sleep-pain interactions.
The researchers found that six hours of total sleep deprivation compared with ad libitum sleep prior to surgical incision correlated with significantly enhanced postoperative mechanical hypersensitivity in the affected paw and prolonged duration of recovery from surgery. In these measures, there were no sex-specific differences. After sleep deprivation, there were no changes in adrenocorticotropic hormone and corticosterone levels. At the onset of sleep deprivation, systemic administration of the nonselective adenosine receptor antagonist caffeine prevented the postoperative increase in hypersensitivity induced by sleep deprivation. The increase in surgical pain levels and duration cause by prior sleep deprivation was prevented by microinjection of the adenosine A2A receptor antagonist ZM 241385 into the median preoptic nucleus (MnPO), eliminating the thermal hyperalgesia induced by sleep deprivation in a group of non-operated rats.
"These data show that even a brief sleep disturbance prior to surgery worsens postoperative pain and are consistent with our hypothesis that adenosine A2A receptors in the MnPO contribute to regulate these sleep-pain interactions," the authors write.