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M Klain

Publications and source records attributed to M Klain.

At least 73 records · Page 4Linked to original sources

Limits of high frequency percutaneous transtracheal jet ventilation using a fluidic logic controlled ventilator.

A study was undertaken on dogs to find the limit of carbon dioxide exchange with high frequency jet ventilation using a fluidic logic controlled oxygen jet ventilator. Fifteen dogs were ventilated through a transtracheal catheter at respiratory rates up to 600 per minute. The following were recorded: aortic, pulmonary artery, pulmonary arterial wedge, and central venous blood pressures; intratracheal pressure, electrocardiogram; inspiratory and expiratory time of the jet; arterial and central venous blood gases; intermittent cardiac output. Normal gas exchange was found up to a respiratory rate of 400 per minute with low tidal volume and low intratracheal pressures. There were no adverse circulatory effects up to a rate of 400 per minute. At rates of 500 and 600 per minute, cardiac contractility was unaffected, but a decreased heart rate and increased peripheral resistance produced a fall in cardiac output. There was no interference with the resumption of spontaneous ventilation during weaning. In a control series of five dogs, apnoeic oxygenation was used. The PaCO2 was allowed to reach 15.96 kPa (120 torr). High frequency jet ventilation was then started at a rate of 600 per minute and decreased in increments to 100 per minute. Arterial blood gases were continuously recorded through an intra-arterial catheter connected to a mass spectrometer. The PaCO2 gradually declined to normal levels as the rate decreased.

Animals

Tracheobronchial toilet without cardiorespiratory impairment.

Suctioning of the tracheobronchial tree during high frequency jet ventilation (HFJV) in two groups of apneic dogs could be prolonged to 2 min without producing significant drops in PaO2, slowing of the pulse or marked hypertension. Arrhythmias were also virtually absent. The controls reacted to suctioning like human patients. A sharp drop in PaO2, an increase in PaCO2 and a change in pulse rate and blood pressure (BP) as well as frequent premature ventricular contractions were observed.

Animals

Percutaneous transtracheal ventilation.

The technique of percutaneous transtracheal ventilation (intermittent jets of oxygen under high pressure, 50 pounds per square inch [psi]) has been used for resuscitation during anesthesia and prior to tracheostomy, and has been established as an important adjunct to life-support techniques. The technical aspects are described together with experimental evidence that intermittent jet ventilation is necessary to eliminate carbon dioxide. The complications occurring with a series of 80 patients are reported along with experimental work in ventilation of dogs with compressed air sources, including truck tires. Emergency physicians should be familiar with this technique and equipment for its use should be readily available in the emergency department. The potential role of transtracheal ventilation in the mobile intensive care unit at accident sites has been explored and appears promising. Conventional airway support techniques should be applied prior to resorting to transtracheal ventilation.

Adolescent

Jet ventilation for fiberoptic bronchoscopy under general anesthesia.

An oxygen jet method ventilating patients during laryngoscopy has been applied to fiberoptic bronchoscopy. A 3.5 mm plastic tube 24.5 cm long was inserted into the trachea through the mouth. An intermittent jet of oxygen at 3.5 atm (50 psi) was applied to this tube using a 1.5 mm ID plastic catheter to ventilate the patient. Anesthesia was accomplished with intravenous thiamylal and Innovar. The patients were paralyzed with continuous succinylcholine. The technique has subsequently been used without complications in more than 1,000 patients. A fluidic ventilator was developed for delivering and controlling the oxygen jet. The airway pressure can be monitored continuously and, by the use of fluidic devices, the jet can be set to cut off automatically if the airway pressure is too high. The above techique for laryngoscopy with the fluidic ventilator was used in 28 patients undergoing fiberoptic bronchoscopy (Olympus 5.7 mm diameter). The airway pressure was continuously monitored with a line attached to the suction port of the bronchoscope. Arterial PCO2 ranged from 23 to 42 mmHg and PO2 from 105 to 325 mmHg. The high PO2 levels were maintained even during suctioning. General anesthesia for fiberoptic bronchoscopy can be performed using an endotracheal tube not smaller than 8 mm internal diameter (ID). The advantages of the oxygen jet technique are that it can be used in smaller patients and that the upper airway can be examined.

Anesthesia, General