Alan S. Tonnesen

Major injury as a unique opportunity to initiate treatment in the alcoholic

A prospective study was performed on the use of a standard outpatient intervention technique to induce inpatient alcoholic trauma patients into accepting alcoholism treatment. Interventions were performed on 17 trauma patients. All patients who underwent intervention accepted treatment and were immediately transferred to a 28-day inpatient treatment facility. Alcoholic trauma patients are highly susceptible to intervention for their disease. We found that intervention performed upon discharge from the trauma service successfully initiates alcoholism treatment.

Therapy of unilateral pulmonary insufficiency with a double lumen endotracheal tube.

Successful therapy of unilateral acute lung disease has been infrequent. The marked compliance difference that exists between the acutely diseased and normal lung may make conventional respiratory therapy ineffective in treating the diseased lung. Vigorous attempts at reexpansion of the involved lung including bronchoscopy, continuous positive pressure ventilation, chest physiotherapy, suctioning, and position changes are usually successful in acute lung disease but were ineffective in the case presented. The use of the double lumen endotracheal tube, Carlens tube, and the application of differential ventilation was a safe and effective modality of therapy when conventional measures failed. The method of ventilation and the patients course are described.

Cardiovascular Effects of Plasma Levels of Thiopental Necessary for Anesthesia

The cardiovascular effects of plasma levels of thiopental necessary for anesthesia were studied using systolic time intervals (STI). In ten healthy patients anesthesia was induced with thiopental, 2–2.5 mg/kg, intravenously, and maintained with an infusion of 1–1.5 mg/kg/min. STI and thiopental plasma levels were measured before induction and when corneal reflex and trapezius muscle response, indicators of anesthetic depth equivalent to response to surgical stimulation, were lost.Significant changes included: an increase in heart rate with induction of anesthesia; a decrease in l/pre-ejection period2— indexed for heart rate (1/PEP2-I) at loss of corneal reflex; a decrease in systolic blood pressure and l/PEP2-I at loss of trapezius muscle response. No other variable was significantly different from control. Control values for STI were in the high-normal range, indicating some sympathetic stimulation. With induction of anesthesia these values decreased to a normal range. Free and total plasma levels were 5.4 and 37.6 μg/ml at loss of corneal reflex; 6.1 and 41.6 μg/ml at loss of trapezius muscle response.In comparison with other studies, thiopental causes less cardiac depression than inhalational agents at approximately the same anesthetic depth. It is concluded from this study in healthy patients that plasma levels of thiopental producing surgical anesthesia result in minimal cardiac depression as determined by systolic time intervals.

Hypophosphatemia--incidence, etiology, and prevention in the trauma patient.

Hypophosphatemia is associated with a number of undesirable physiologic consequences and has been reported to occur frequently in trauma patients. We studied patients in the immediate posttraumatic period to document a) the decrease in serum P, b) renal P excretion, and c) the response to prophylactic PO4 administration. In both group 1 (n = 12) and group 2 (n = 10) patients, we measured serum P, creatinine, ionized Ca, urinary P excretion, and creatinine clearance daily for the first 3 to 4 days postinjury. Patients in group 2 also received 0.5 mmol/kg.day of PO4 for the first 48 h after admission. Group 1 patients exhibited a significant (p less than .05) decrease in serum P over the first 24 h (1.00 +/- 0.30 to 0.75 +/- 0.23 mmol/L). In contrast, group 2 patients did not demonstrate a decrease in serum P. Urinary P excretion in group 1 accounts for the observed decrease in serum P. The results of our study show that the immediate posttraumatic period is associated with a decrease in serum P and massive urinary P excretion. We also showed that prophylactic administration of 0.5 mmol PO4/kg.day prevents serum P decrease.

Beneficial effect of delivery in a patient with adult respiratory distress syndrome.

The management of adult respiratory distress syndrome (ARDS) often requires support of respiratory and cardiovascular function and is particularly difficult in pregnant patients. We report a patient in her third trimester who developed ARDS requiring mechanical ventilation and PEEP. Following delivery her pulmonary status improved markedly

Endotracheal Tube Cuff Residual Volume and Lateral Wall Pressure in a Model Trachea

The authors constructed a D-shaped tracheal model with an elastic posterior wall, thus simulating normal tracheal anatomy more closely than previous models. The performance of 9-10 tracheal tube cuffs, of 2-3 different tube sizes (7.0-10.0 mm, ID), from six different manufacturers were tested in the model. Cuff residual volumes ranged from 1.78 to 27.35 ml. Cuff pressure and lateral wall pressures exerted by the cuff on the model were measured at the time a seal was achieved which just prevented leakage of water past the cuff. When a seal was achieved with a volume of air in the cuff less than cuff residual volume, wall pressure tended to be low (less than 35 torr) and cuff pressure closely approximated wall pressure. There was no relationship between cuff brands in the wall pressure required to effect a seal in the model. The authors conclude that intratracheal tubes should have cuffs with large residual volumes. This would permit some latitude in tube size selection while ensuring that a seal could be achieved before the cuff is inflated to its residual volume.

Relation between lowered colloid osmotic pressure, respiratory failure, and death.

Plasma colloid osmotic pressure was measured each day in 84 intensive care unit patients. Probit analysis demonstrated a direct relationship between colloid osmotic pressure (COP) and survival. The COP associated with a 50% survival rate was 15.0 torr. COP was higher in survivors than in nonsurvivors without respiratory failure and in patients who recovered from respiratory failure. We conclude that lowered COP is associated with an elevated mortality rate. However, the relationship to death is not explained by the relationship to respiratory failure.

Intracranial hypertension secondary to tension subcutaneous emphysema.

A patient with severe closed head injury and tension subcutaneous emphysema developed intracranial hypertension unresponsive to conventional treatment. Subcutaneous air drainage controlled the intracranial pressure. The subcutaneous pressure was directly correlated with intracranial pressure.

Transesophageal echocardiographic study of venous air embolism following pneumomediastinum in dogs.

BackgroundContinuous venous air emboli have been detected in the inferior vena cava and smaller veins using transesophageal echocardiography in patients with positive pressure ventilation and associated pulmonary barotrauma. The authors hypothesized that gas entered the venous circulation, following dissection of small vessels at several sites in the subcutaneous or retro-peritoneal soft tissues.ObjectiveThe present study was designed to determine if a comparable venous gas embolism occurred in anesthetized dogs, after creation of a pneumomediastinum.DesignUsing transesophageal echocardiography, we observed 11 anesthetized dogs mechanically ventilated with positive end-expiratory pressure, while mediastinal air was introduced through a catheter at a rate of 0.5 ml/kg/min.ResultsA continuous stream of bubbles appeared in the inferior vena cava in 8/11 dogs (73%) after an infusion period of 280±81 min. A surge of bubbles was commonly observed following abdominal massage and was often associated with a transient decrease of end-tidal carbon dioxide tensions. In two dogs the air infusion rate was reduced to 0.25 mg/kg/min, and bubbles were detected in the inferior vena cava for as long as 16 consecutive hours.ConclusionWe conclude that in anesthetized dogs mechanically ventilated with positive end-expiratory pressure, unremitting pneumomediastinum is usually followed by continuous venous air embolism. A mechanism hypothesized for venous gas entry in the clinical condition of positive end-expiratory pressure ventilation with subcutaneous gas is suggested by this model.