ABSTRACT
BACKGROUND: We previously demonstrated that lubrication of an endotracheal tube (ETT) cuff with K-Y™ jelly strongly and significantly inhibited the increase in cuff pressure during nitrous oxide (N2O) exposure in vitro. However, in our previous study, we identified critical differences between some influential factors, such as the amount of lubricant retained on the cuff, and studied temperature differences between laboratory and clinical conditions. Therefore, it remained unclear whether this effect holds true in clinical settings. METHODS: We first sought to study how changes in the amount of K-Y™ jelly and temperature influence the inhibitory effects of the lubricant on the increase in N2O-induced cuff pressure in vitro. Furthermore, we aimed to determine whether the application of K-Y™ jelly inhibits the increase in ETT cuff pressure during general anesthesia using N2O in adult patients. RESULTS: In the laboratory studies, we found that K-Y™ jelly inhibited the cuff pressure increase dose-dependently when the dose of K-Y™ jelly was varied (P = 0.02), and that such an inhibitory effect decreased with an increase in the studied temperature (P = 0.019). In the clinical study, lubrication with K-Y™ jelly slightly, but significantly, delayed the increase in ETT cuff pressure during general anesthesia with N2O (P = 0.029). However, the inhibitory effect in the clinical settings was smaller than that in vitro. CONCLUSIONS: Lubrication of the ETT cuff with K-Y™ jelly may delay the increase in cuff pressure during general anaesthesia with N2O. However, the clinical significance of this effect may be limited. TRIAL REGISTRATION: UMIN Clinical Trials Registry: UMIN000031377 on March 1, 2019.
Subject(s)
Cellulose/analogs & derivatives , Glycerol/pharmacology , Intubation, Intratracheal/methods , Lubrication , Nitrous Oxide/administration & dosage , Phosphates/pharmacology , Pressure , Propylene Glycols/pharmacology , Surgical Equipment , Cellulose/administration & dosage , Cellulose/pharmacology , Dose-Response Relationship, Drug , Female , Glycerol/administration & dosage , Humans , In Vitro Techniques , Male , Middle Aged , Phosphates/administration & dosage , Propylene Glycols/administration & dosage , Temperature , Time FactorsABSTRACT
We detected congenital aqueductal stenosis from CT images taken for the differential diagnosis of a post-dural puncture headache. A history of multiple spinal taps for anesthesia and the nature of headaches led us to a suspected diagnosis of headache caused by intracranial hypotension at variance with image findings diagnostic of hydrocephalus, perplexing us in the differential diagnosis. Hydrocephalus was of congenital type, having no causal relationship with past multiple spinal taps. Congenital aqueductal stenosis varies in severity from infancy-onset one to accidental one diagnosed from images like the current case. Since treatment may differ between hydrocephalus and intracranial hypotension which are diametrically opposite to each other in pathophysiology, it is essential to differentiate a headache in an overall view of a history, physical examination, and image findings.
