Systemic air embolism following manual lung inflation

Abstract

A case is reported in which a young man undergoing exploratory thoracotomy following a gunshot wound had a cardiac arrest during reinflation of the collapsed lung. Systemic air embolism was suspected as the cause. Subsequent neurological examination and C.T. scan demonstrated a lesion ascribable to this. Discontinuation of nitrous oxide, aspiration of left heart chambers and a head-down position are recommended as immediate treatment if this diagnosis is made. In cases with piercing lung trauma high inflation pressures should be avoided to prevent embolism.

Is Emergency Thoracotomy Always the Most Appropriate Immediate Intervention for Systemic Air Embolism After Lung Trauma?

“…Most reported cases of SAE associated with isolated penetrating lung injury have a fatal outcome. 1,8,9,[11][12][13][14][15][16][17][18][19][20] In one series of 61 patients with documented SAE, 15 patients had blunt trauma and 46 patients had penetrating trauma. 9 The blunt group had a mortality rate of 80%, and the penetrating group rate was 48%.…”

“…Indeed, of the 107 or so published cases of SAE, 8,9,[11][12][13][14][15][16][17][18][19][20] no effort to limit airway pressures or to selectively ventilate the uninjured lung (in unilateral lung trauma) was mentioned except in those described by Saada et al 11 Using transesophageal echocardiography, these authors demonstrated (1) the cessation of intracardiac air emboli in between positive pressure cycles, and (2) the decrease of emboli when ventilatory pressures and volumes were decreased. 11 Based on intuition and the experience of Saada et al, 11 I believe it is appropriate to re-examine the heretofore-neglected airway and breathing components of the resuscitation of patients who are at risk or suspected of having SAE.…”

“…In the ensuing emergency thoracotomy, the nonfunctional heart shows little evidence of direct trauma, and air is seen in the coronary arteries, left cardiac chambers, or the aortic root. 1,9,[11][12][13][14][15][16][17][18][19][20] Less frequently, the development of neurologic deficit or seizures in previously conscious patients without obvious head injury may implicate cerebral air embolism. 11,16 The current recommended treatment of SAE associated with unilateral lung injury is immediate thoracotomy, in the emergency department if necessary, to clamp the hilum of the injured lung to arrest the continuous passage of air into the coronary, cerebral, and other systemic arteries.…”

“…During thoracotomy, air in coronary arteries, left atrium and ventricle, and the aorta may be seen or aspirated. 8,9,[11][12][13][14][15][16][17][18][19][20] A contributor to the poor prognosis associated with SAE could be the low index of suspicion among many physicians who deal with trauma. Successful resuscitation is made difficult when the main source of insult-continuous passage of gas from the ventilator into the heart and the brain-is not recognized, or recognized late, after the chest is open.…”

Death caused by air embolism associated with lower limb and pelvic trauma

“…More invasive treatment has been attempted with variable success. Direct ventricular or central venous catheter aspiration may produce clinical improvement 1,28,29 . External cardiac massage is of little benefit in patients with chest trauma, and may cause additional injury.…”