The laryngeal mask simplifies airway management during percutaneous dilational tracheostomy.

The Laryngeal Mask Airway (LMA) is used for many procedures which previously required endotracheal intubation. Percutaneous Dilational Tracheostomy (PCT) facilitates the bedside insertion of a tracheostomy tube in the Intensive Care Unit. Most patients requiring this procedure are intubated with a conventional endotracheal tube. Insertion of a LMA has advantages over tracheal intubation for PCT mainly because the artificial airway lies remote from the operating field. Three cases are reported to illustrate these advantages.

Detection of experimentally produced acute pulmonary arterial occlusion by methyl iodide-131 inhalation imaging.

Methyl iodide-131 (CH3I-131) is described as an agent for detection of acute experimentally produced pulmonary arterial occlusion in dogs. When gaseous CH3I-131 is inhaled, radioactivity passes instantaneously from the alveoli to the lung capillary bed. Where pulmonary blood flow exists, activity is washed out into the systemic circulation, but in areas of blood stasis, a transient pulmonary "hot spot" remains. CH3I-131 is easily produced and inexpensive, but administration is awkward and strict radiation safety precautions are mandatory.

Distribution of leukocytes labeled with In-111 oxine in dogs with acute inflammatory lesions.

The biodistributions of In-111 oxine (with and without leukocyte labeling) of Ga-67 citrate and of In-111 chloride were compared in 30 dogs with chemical and bacterial abscesses and acute joint inflammation. Serial blood samples were taken and tissues radioassayed at 24 hr. The concentration of In-111-oxine leukocytes in all three types of inflammatory lesion was invariably much higher than that of Ga-67 injected simultaneously. For bacterial abscesses, the mean abscess-to-muscle concentration ratio was 3,000 for labeled leukocytes and 72 for Ga-67. Aqueous buffered In-111 oxine sulfate solution appeared better for labeling leukocytes than In-111 oxine in ethanol. When In-111 oxine was not incubated with leukocytes before injection, or if the cells were poorly labeled or damaged, the abscess localization was often inferior to that of gallium. Localization of In-111 chloride also appeared inferior to that of gallium. No significant difference in distribution in the major organs or inflammatory lesions was demonstrable between labeled suspensions of "pure"neutrophils harvested by elutriation and "mixed"cell suspensions of leukocytes after erythrocyte sedimentation with hydroxyethyl starch. For both types of leukocyte suspension labeled with In-111 oxine, the average recovery of cell-bound activity in the circulating blood at 4 hr was 32% of the administered activity, inferior to that of DFP-32. It is concluded, therefore, that In-111 oxine is a more effective agent than Ga-67 for the detection of acute focal inflammatory lesions if leukocytes are properly labeled, but current techniques are unsatisfactory for the study of neutrophil kinetics.