Anesthesia and analgesia
-
Abnormalities of the cornea and conjunctiva occur in association with neurological diseases, nocturnal lagophthalmos, coma, infection, and mechanical ventilation. We investigated the incidence and causes of ocular surface disorders in critically ill patients. In a retrospective study, the presence of conjunctivitis and corneal erosion was determined by reviewing the medical charts of 143 mechanically ventilated patients (intensive care unit [ICU] stay > or =7 days). ⋯ Protective eyelid taping was effective in preventing and treating the corneal erosion. In conclusion, the critically ill often develop ocular surface disorders, especially when sedated and immobilized. A close relationship was observed between these conditions and the inability to close one's eyes.
-
Anesthesia and analgesia · Aug 1997
The effects of chronic tacrine therapy on d-tubocurarine blockade in the soleus and tibialis muscles of the rat.
Tacrine (THA) is an anticholinesterase drug used to manage Alzheimer's dementia, but it is not clear how its chronic use might affect response to nondepolarizing muscle relaxants. We determined the magnitude and time course of the effects of chronic oral THA and of intravenous (IV) THA on d-tubocurarine (dTC) blockade at the soleus and tibialis muscles. Six groups of adult rats were given 10 mg/kg THA twice daily by gavage for 1, 2, 4, or 8 wk (chronic THA groups), or 1 mL of saline twice daily by gavage for 1-8 wk (control), or IV THA approximately 20 min before (acute), and the cumulative dose-response curves of dTC at the tibialis and soleus muscles were determined during indirect train-of-four stimulation in the anesthetized, mechanically ventilated rat. ⋯ Chronic THA increased both the ED50 and ED95 of dTC 1.5- to 2-fold (P > or = 0.05), and this effect tended to decrease with duration of THA therapy. We conclude that chronic THA therapy in rats causes resistance to dTC, with a tendency for the resistance to decrease with time, probably because of down-regulation of postsynaptic acetylcholine receptors. The same may apply to Alzheimer's patients taking THA chronically.
-
Anesthesia and analgesia · Aug 1997
Randomized Controlled Trial Comparative Study Clinical TrialEpidural meperidine after cesarean section: the effect of diluent volume.
We investigated the effect of diluent volume on analgesia and systemic absorption from epidural meperidine after cesarean section in a randomized, double-blind study. At the first request for postoperative analgesia, 36 parturients were given epidural meperidine 25 mg diluted with saline to either 2 mL (12.5 mg/mL), 5 mL (5 mg/mL), or 10 mL (2.5 mg/mL). Visual analog pain scores measured in the first 30 min were greater in the 2-mL group compared with both the 5-mL group (P = 0.028) and the 10-mL group (P = 0.031). ⋯ No adverse side effects were recorded. Previous work has suggested that injection of epidural opioids in large volumes increases the potential risk of respiratory depression from cephalad spread of the drug. Therefore, we conclude that analgesia is optimum when epidural meperidine is administered diluted to 5 mL.