Airway Management Strategy Using Seldinger Minitracheostomy Kit to Prevent Airway Obstruction after Oral Cancer Surgery: A Retrospective Study.

A minitracheostomy (MTS) is performed after surgery for oral cancer at our institution in patients who are at risk of postoperative airway obstruction. The aim of this study was to evaluate outcomes of preventive airway management with this procedure. A total of 105 patients undergoing preventive airway management with a Seldinger MTS kit after oral cancer surgery between October 2014 and March 2020 were enrolled. Information on patient characteristics, time required for the MTS, duration of tracheal cannula placement, and MTS-related complications was obtained from both the medical and anesthesia records. In addition, the numbers of postoperative instances of tracheotomy between April 2009 and September 2014 and extubation between October 2014 and March 2020 were also counted for a comparison. The time required for an MTS was 3.2±2.6 min. Minor complications, including mild subcutaneous or mediastinal emphysema and bleeding, were found in 5 patients, but all recovered in a short time. The median duration of tracheal cannula placement was 2 days, with a range of from 0 to 8 days. A total of 348 oral cancer surgeries were performed between April 2009 and September 2014. Among patients undergoing these procedures, 111 underwent a tracheostomy (32%), 235 extubation (68%), and 2 sustained intubation. A total of 580 oral cancer surgeries were performed between October 2014 and March 2020. Here, 121 patients underwent a tracheostomy (21%), 105 an MTS (18%), and 354 extubation (61%). The results suggest that an MTS can be performed safely and smoothly with no significant complications. They also suggest that an MTS reduces the need for a full tracheostomy and the risk of airway obstruction after extubation. We conclude that airway management strategy with an MTS is a useful option in preventing airway obstruction following oral cancer surgery.

Intracellular Ca2+ mobilization pathway via bradykinin B1 receptor activation in rat trigeminal ganglion neurons.

Bradykinin (BK) and its receptors, B1 and B2, in trigeminal ganglion (TG) neurons are involved in the regulation of pain. Recent studies have revealed that B1 receptors are expressed in neonatal rat TG neurons; however, the intracellular signaling pathway following B1 receptor activation remains to be elucidated. To investigate the mechanism by which B1 receptor activation leads to intracellular Ca2+ mobilization, we measured the intracellular free Ca2+ concentration ([Ca2+]i) in primary-cultured TG neurons. The application of Lys-[Des-Arg9]BK (B1 receptor agonist) increased the [Ca2+]i in these TG neurons even in the absence of extracellular Ca2+. Pretreatment with inhibitors of ryanodine receptors or sarco/endoplasmic reticulum Ca2+-ATPase suppressed the increase in Lys-[Des-Arg9]BK-induced [Ca2+]i. The Lys-[Des-Arg9]BK-induced [Ca2+]i increase was unaffected by phospholipase-C inhibitor. B1 receptor activation-induced [Ca2+]i increase was suppressed by phosphodiesterase inhibitor and enhanced by adenylyl cyclase inhibitor. These results suggest that B1 receptor activation suppresses intracellular cAMP production via adenylyl cyclase inhibition and mobilizes intracellular Ca2+ via ryanodine receptors that access intracellular Ca2+ stores.