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A method for pediatric airway support was evaluated for the situation when mask ventilation or intubation is impossible. Mongrel dogs were sedated, intubated, and allowed to breathe room air for 30 min. Baseline variables were recorded, and the airway obstructed. After 2 to 3 min of hypoxia, arterial blood gas and hemodynamic data were again recorded. A percutaneous cricothyroid membrane puncture (PCMP) was then performed with a 12-ga iv catheter. Studies were carried out both in the presence and absence of spontaneous ventilatory efforts. With spontaneous ventilation, continuous low flow (1.0 L/min) oxygen insufflation provided oxygenation for 30 min and reversed increases in mean arterial pressure, pulmonary artery pressure (PAP), and systemic and pulmonary vascular resistance that had been produced by the obstruction. Respiratory acidosis occurred but was well tolerated. With paralyzed animals, whose ventilation was supported by a self-inflating bag with 10.0 L/min of oxygen, all hemodynamic variables except PAP returned to normal, oxygenation was excellent, and PaCO2 values were maintained at steady, but elevated levels. Complications included bilateral tension pneumothorax in one animal. This experimental study supports anecdotal experiences where PCMP has been used and has proven lifesaving when standard resuscitative measures to establish a clear airway have failed.

Grade inflation appears to be related to two different faculty characteristics on this particular campus, at least.

Emission spectra and ionization are compared in premixed flames of CH 4 burning in commercial F 2 (0.4% O 2 ) with those burning in purified F 2 . Oxygen impurity is reduced to below 0.02% in the purified F 2 by reaction with SbF 5 . No appreciable differences exist between the spectra of flames burning in commercial and purified F 2 ; both are dominated by bands of CHF and CH. CH emission is thus an intrinsic property of F 2 -hydrocarbon combustion. In contrast, ionization (as measured by a Langmuir probe) is reduced to an undetectable level in flames with purified F 2 and is roughly proportional to O 2 concentration in flames with unpurified F 2 . Ionization is thus not an inherent property of F 2 -hydrocarbon combustion.