[Massive subcutaneous emphysema following percutaneous tracheostomy].

Although percutaneous dilatational tracheostomy (PDT) is fast becoming the method of choice for securing an airway in chronic ventilated patients in an intensive care unit (ICU). Subcutaneous emphysema is an unusual and sometimes lethal complication which may extend the length of stay in the ICU. We report a case of massive subcutaneous emphysema without tracheal wall laceration that occurred in the ICU after PDT.

The mechanisms of propofol-mediated hyperpolarization of in situ rat mesenteric vascular smooth muscle.

Unlabelled: Previously, we reported that propofol hyperpolarizes vascular smooth muscle (VSM) cells of small arteries and veins. The current study was designed to determine whether propofol-mediated hyperpolarization is the result of specific effects on potassium channels known to exist in VSM and on steps in the intracellular nitric oxide (NO), cyclic guanosine monophosphate (cGMP), and cyclic adenosine monophosphate (cAMP) second messenger pathways. VSM transmembrane potentials (E(m)) were measured in situ in sympathetically denervated, small mesenteric arteries and veins of Sprague-Dawley rats.

The effects of propofol on neural and endothelial control of in situ rat mesenteric vascular smooth muscle transmembrane potentials.

Unlabelled: We indirectly assessed the in vivo effect of propofol on sympathetic neural and endothelial control of vascular smooth muscle (VSM) tone in Sprague-Dawley rats by measurement of in situ responses of VSM transmembrane potential (E(m)) in intact, small mesenteric arteries and veins superfused with physiologic salt solution. Measurements were made before, during, and after propofol infusion (10 and 30 mg x kg(-1) x h(-1)) in sympathetically innervated and locally denervated vessels. Propofol's effect on E(m) response to superfusion with acetylcholine (ACh), in physiologic salt solution also containing NG-nitro-L-arginine-methyl-ester and indomethacin, was determined in innervated vessels.