Evaluation of Seldinger Technique Emergency Cricothyroidotomy versus Standard Surgical Cricothyroidotomy in 200 Cadavers

Background: Percutaneous cricothyroidotomy is a lifesaving procedure for airway obstruction in trauma victims who need airway establishment and cannot be intubated or in whom intubation has failed.

Methods: The purpose of this study was to examine whether there is a training effect using Seldinger technique emergency cricothyroidotomy (group 1; Arndt Emergency Cricothyroidotomy Catheter Set; Cook Critical Care, Bloomington, IN) versus standard surgical cricothyroidotomy (group 2). Twenty emergency physicians performed five cricothyroidotomies with each method in a total of 200 human cadavers, comparing efficacy and safety (speed, success rate, and injuries).

Results: Seven attempts in group 1 and six in group 2 had to be aborted. Time intervals from the start of the procedure to location of the cricothyroid membrane were not significantly different between the groups. However, time to tracheal puncture (P < 0.01) and time to first ventilation (P < 0.001) were significantly longer in group 2. No time effect could be observed in both groups. The airway was accurately placed into the trachea through the cricothyroid membrane in 88.2% (82 of 93) of the cadavers in group 1 and in 84.0% (79 of 94) in group 2 (not significant). No injuries were observed in group 1, whereas there were six punctures of the thyroid vessels in group 2 (P < 0.05).     

Absorption of β-methyl-digoxin determined after a single dose and under steady state conditions

Summary Single doses of -methyl-digoxin 0.4 mg were given to groups of 17 – 18 healthy volunteers as an intravenous infusion lasting 2 hours, or orally as Lanitop Liquidum^® or Lanitop^® tablets. The serum glycoside concentration and urinary glycoside excretion were measured over 8 and 32 h. The absolute bioavailability from the oral preparations in comparison with the infusion was lower for the first 8 h than for the entire 32 h of the investigation; the relative bioavailability from tablets was the same as from the solution for both periods. For both periods the area under the serum concentration/time curve and the urinary glycoside excretion were significantly lower after administration of the tablets than after intravenous infusion. Taking the average of both parameters, the absolute bioavailability of -methyl-digoxin was about 80% from the solution and about 70% from the tablets. In 18 patients undergoing intravenous or oral therapy with -methyl-digoxin steady state glycoside concentrations were compared in a cross-over study of intravenous maintenance therapy with Lanitop^® ampoules or oral treatment with Lanitop^® tablets. For a standard daily dose of 0.2 mg -methyl-digoxin the serum concentrations were 1.35±0.10 ng/ml during both intravenous and oral administration. The intra-individual variation in glycoside concentration after changing from intravenous to oral maintenance therapy, or vice versa, was about the same as during continued intravenous or oral administration. It is concluded that the rate of rise of serum concentration after a single dose may be a useful indicator of the rate of absorption, but that the area under the serum concentration/time curve and the urinary glycoside excretion up to 32 h are unsuitable for determining equivalent doses of different formulations or routes of administration of digitalis glycosides.     

Embryological development and prevalence of thumb flexion creases

A study of the embryological development and morphology of the thumb flexion creases is presented. We used 178 human fetuses, at 6-20 weeks of gestational age, and 225 normal adults, aged 19-81 years, to observe the morphology and the timing and location of the appearance of the flexion creases. Most creases, that is, the regular, extra, and oblique creases, were found to develop concurrently with the appearance of the fetal volar pads, apparently independently of the thumb flexion movements. Although the regular creases usually appear to be simple, single creases, they seem to be formed by the radial and ulnar lateral crease segments that develop inwards from each lateral side. Our observations also suggest that the oblique and extra creases on the proximal phalanx of the thumb should be considered as common or "regular" creases, rather than anomalies, because of their high frequency in fetuses and in normal healthy adults.     

Optimizing the Lymphocyte Transformation Test in Whole Blood. II. Kinetics of Thymidine Incorporation

From the 2nd day of incubation on, the thymidine incorporation per incubated lymphocyte increased exponentially with time. The duration of the exponential growth phase was inversely correlated with the number of cells. Under optimum conditions the average time for the doubling of thymidine incorporation (Ti) was 15.7 h. Ti after 1 day of incubation was taken as an equivalent for the number of proliferating cells. It was estimated that less than 20% of the incubated lymphocytes are stimulated by PHA under optimum conditions.

In Ficoll-separated mononuclear cells, the percentage of cells stimulated by PHA was lower than in whole blood; the proliferation rate was not decreased.