Stephen Z. Turney

Management of major tracheobronchial ruptures in patients with multiple system trauma

Major tracheobronchial injury presents special problems in the context of multiple system trauma. A 14-year review of a clinical experience revealed eight patients who had operative repair of major bronchial or intrathoracic tracheal injuries. The diagnosis was suspected by subcutaneous emphysema, and especially by persistent pneumothorax or a significant air leak. Bronchoscopy confirmed the diagnosis in all patients before thoracotomy. All eight patients had multiple system injuries. All five with abdominal injuries were hypotensive at admission and underwent celiotomy before thoracotomy. The decision to perform thoracotomy or celiotomy first in patients with major tracheobronchial injuries and concomitant abdominal trauma must be individualized. If both injuries are recognized simultaneously and the patient is hemodynamically unstable but has adequate oxygenation and ventilation, the celiotomy can be performed first. On the contrary, if oxygenation and ventilation are the most threatening problems in a hemodynamically stable patient despite evidence of hemoperitoneum, the bronchial repair should have priority.

Thymectomy for myasthenia gravis: 14-year experience.

Forty-eight consecutive patients with myasthenia gravis (MG) attended by generalized weakness were treated by complete thymectomy, performed transsternally in 46 patients and through a left thoracotomy in two with thymomas. There were no operative deaths. A 12-year-old child with fulminating MG died of acute pneumonia shortly after hospital discharge. Of the remaining 47 evaluable patients, thymectomy resulted in complete remission in six, marked improvement with a reduced need for medication in 20, and mild improvement on the same dosage of medication in 18. Neither the age of the patient, nor the histopathology of the excised thymus, nor the postoperative change in acetylcholine receptor antibody titer were found to have a significant influence on the response to thymectomy. If the ten patients who were 20 years of age or younger were excluded, the patients with a shorter duration of MG achieved a better response to operation. The authors conclude that thymectomy is effective treatment for MG, regardless of the age of the patient or the type of thymic pathology.

Tracheal rupture and atlanto-occipital dislocation : case report

Blunt trauma associated with tracheal rupture (TR) or atlanto-occipital dislocation (AOD) occurs rarely. Survival after sustaining either injury is even more uncommon. We describe a case of a patient who remarkably survived both injuries concurrently.

The Continuous Measurement of Pulmonary Gas Exchange and Mechanics

Abstract A system for breath-by-breath measurement of respiratory gas exchange and airway mechanics from analog recordings is described. The essential components are a pneumotachometer for measuring air flow, a manometer for airway pressure, and a mass spectrometer for continuous rapid analysis of O 2 , CO 2 , and N 2 . Analog signals from these instruments are recorded, manual measurements done for each breath, and calculations made of variables such as anatomical dead space, alveolar ventilation, oxygen consumption, carbon dioxide production, compliance, and resistance. Use of the Engstrom ventilator permits simplified calculation of nonelastic resistance due to its wave form. The basic calibration routine of the components of this system is described and the mathematical methods are presented. Its usefulness in the management of the critically ill patient is illustrated.

Automatic Respiratory Gas Monitoring

Abstract A unique system is described for automatic sequential sampling of airway gases operating on a 24-hour-a-day basis in a 12-bed Shock Trauma Recovery Unit. A series of 50-foot-long sampling lines run from each bed area to a manifold. A small digital calculator each hour automatically places a mass spectrometer in an operative mode, switches a manifold to a calibrating gas, sequentially samples each occupied bed, prints out calculated data, and then reverts to standby status. The analog waveforms from the spectrometer are conditioned for high and low levels corresponding to inspiratory and peak expiratory values of oxygen and peak expiratory carbon dioxide. The waveforms are counted for respiratory rate, and the respiratory quotient is computed. These data are used, in lieu of frequent blood gas determinations, in making estimates of arterial pCO 2 for adjusting respirators and to monitor airway oxygen levels. The system in conjunction with a pneumotachometer is compatible with on-line computer analysis of respiratory gas exchange and mechanics. Using the system, similar data may be obtained off line by collecting mixed expired gases using more conventional techniques and immediate bedside measurement.

On-line respiratory gas monitoring

Abstract An automated system for monitoring vital signs and respiratory gases is described. By careful selection of analog and digital hardware, a relatively small and inexpensive system can be made to perform complex monitoring functions on a practical clinical basis. This system automatically monitors and records vital signs and respiratory gases from 12 beds in our Trauma Unit by time-sharing the use of a mass spectrometer and other instrumentation under control of a small computer. Automatic measurement is performed on heart rate, temperature, aterial pressures, mean central venous pressure, respiratory O2 and CO2 waveforms, and respiratory rate.

Respiratory Monitoring: Recent Developments in Automatic Monitoring of Gas Concentration, Flow, Pressure, and Temperature

Abstract Advances in instrumentation and programming techniques have resulted in the expansion of a previously reported 12-bed respiratory gas-concentration monitoring system to now include automatic calibrated measurements of bidirectional airflow, airway pressure, and airway temperature as well as other vital signs (rectal temperature, arterial blood pressure, central venous pressure, and heart rate). The more expensive hardware, including a programmable digital desk calculator, interfacing, a mass spectrometer, signal conditioners, and a major portion of the airflow instrumentation, are time-shared to provide an acceptable per-bed cost. Calculated and edited measurements of pulmonary mechanics (tidal and minute volume, mean and end-expiratory airway pressures, compliance, resistance, respiratory rate) and gas exchange (oxygen consumption, carbon dioxide production, respiratory exchange ratio, alveolar P O 2 , and alveolar P CO 2 ) are printed out and stored in an extended memory. The memory is accessed by a second calculator, which prints out summaries of data every 8 hours, correlates off-line blood gases and other measurements with automatically acquired data, and communicates with a commercial time-sharing system for more sophisticated data processing.

An Expert System for the Diagnosis, Treatment, and Triage of Head Injuries in Remote Environments

We describe the development of an expert system, TRAUMA ADVISOR, to aid clinical staff in remote locations in the diagnosis, treatment, and triage of trauma victims with head injuries. The expertise was derived from the current literature, an experienced trauma neurosurgeon, a committee of trauma physicians, and a large trauma database. The emphasis was placed on variables obtainable in the field by emergency medical personnel. The program, developed on an expert system shell, runs on a laptop or desktop IBM-compatible 80286 (or better) personal computer.

A Bayesian Approach to the Detection of Acute Disorders in a Respiratory Intensive Care Unit

Acute pulmonary and systemic disorders occur in mechanically ventilated intensive care patients frequently enough to be of concern. We selected twelve routinely monitored parameters in order to detect certain of these acute disorders (specifically, pneumothorax, pulmonary embolism, ARDS, and sepsis) before they lead to obvious clinical distress. A systematic approach to early detection utilizing changes in the twelve parameters was developed using the sequential Bayesian method. Fifty patients were monitored over a period of one to several days. Six of these patients developed one of the four disorders under study as determined by conventional diagnostic means, such as by x-ray. An examination of the records of these six patients over the time period prior to the actual diagnosis showed that the disorders of three of these six would have been predicted by our Bayesian approach.