Cricothyroid Membrane Puncture: Oxygenation and Ventilation in a Dog Model using an Intravenous Catheter

Cote CJ, Eavey RD, Todres ID, Jones DE Critical Care Medicine 1988 Vol 16 Pages 615-619

A method for pediatric airway support was evaluated for the situation when mask ventilation or intubation is impossible. Mongel dogs were sedated, intubated, and allowed to breathe room air for 30 mins. Baseline variables were recorded, and the airway obstructed by packing the oropharynx with gauze, kinking the tongue, and taping a surgical glove around the mouth. After 2-3 minutes of hypoxia, arterial blood gases and hemodynamic data were again recorded. A percutaneous cricothyroid membrane puncture (PCMP)was then performed with a 12 gauge IV catheter. Studies were carried out both in the presence and absence of spontaneous ventilatory efforts. With spontaneous ventilation, continuous low flow (1.0 lpm) oxygen provided oxygenation for 30 minutes and reversed increases in mean arterial pressure, pulmonary artery pressure, and systemic and pulmonary vascular resistance that had been produced by the obstruction. Respiratory acidosis occurred but was well tolerated. In the two animals where fresh gas flow was increased suddenly to 10 lpm, there were immediate, life-threatening increases in intrathoracic pressure requiring urgent decompression by removing the throat packs. With paralyzed animals, ventilation was supported by a self-inflating bag attached to the IV cannula via a 3 mm pediatric endotracheal tube adapter. Peak airway pressure measured at midtrachea in two dogs varied from 10-16 mmHg. Of special note were the extraordinarily high inflation pressures required to force oxygen from the IV catheter into the trachea. This necessitated long, slow positive-pressure breaths (10-12/min.) which were extremely tiresome for the anesthesiologist and required frequent personnel changes. With 10 lpm oxygen flow, all hemodynamic variables except for pulmonary artery pressure returned to normal, oxygenation was excellent, and PaCO2 values were maintained at steady, but elevated levels. Complications included bilateral tension pneumothorax in one animal. In the presence of spontaneous respiratory effort and near-total airway airway obstruction, all physiologic alterations resulting from hypoxemia were reversed with low flow oxygen delivered through a PCMP; however, mild degrees of hypercarbia persisted. The findings suggest that an underlying healthy cardiovascular system will tolerate profound respiratory acidosis for prolonged periods of time. In the absence of spontaneous respiratory efforts, the study further demonstrated that oxygenation as well as satisfactory ventilation, i.e., the elimination of CO2, could be maintained for at least 30 mins. in dogs weighing up to 30 kg. 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. PCMP may be lifesaving and provide the time for initiating definitive airway control, but must be employed only when standard airway management, i.e., "sniffing position", oral airway, bag and mask ventilation, and tracheal intubation, have failed.