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Differences in handgun bullet diameter, expansion, and penetration (no exit) versus perforation (with exit) may be the cause of variable blood pressure effects after thoracopulmonary injury. Forty nonlethal isolated gunshot wounds of the thorax were evaluated excluding wounds of the heart, great vessels, and spinal cord. Chest radiographs were assessed for bullet base diameter, bullet expansion, and wound length. Large bullets were defined as having radiographic base images of 9 mm or more in diameter. Systolic blood pressures were compared between penetrating large and small bullet groups and with perforating wounds. Response times and demographics were compared. Wounds caused by large bullet penetration resulted in lower initial systolic blood pressures than wounds caused by small bullet penetration (98 vs 125 mm Hg, P < 0.05). The average age, transport time, and wound length were similar among the bullet groups. We conclude that penetrating thoracopulmonary wounds caused by large bullets resulted in lower initial systolic blood pressure.
THE HEMODYNAMIC EFFECTS of thoracopulmonary injury have not been quantitatively studied in human subjects. Perceptions of specific factors causing shock, dyspnea, or pain have relied upon cumulative field experiences and anecdotes. In the early part of the twentieth century the military surgeon LaGarde noted that the change from 11.5 mm-diameter nonjacketed rifle bullets moving 400 m/second to that of 7.62 mm jacketed rifle bullets moving more than 700 m/second resulted in less severe thoracopulmonary wounding stating:
The frontage of the jacketed bullet being much less ... the wound of the lungs were so trivial that it was difficult to restrain the men in the recumbent position ... many of them had neither dyspnea, pain, nor hemoptysis ... Shock is not always present . .. pain is not constant. It is sometimes severe when rib fractures complicate the chest wound and when the pleura is more or less involved with trauma.1
The above observations remained valid until later twentieth-century developments in military bullet design. The change in center of gravity found in Spitzer bullets reduced their stability within tissue; other rifle bullets moving 800 to 1000 rn/second may eject lead from the open base of the round or through cannelure rupture.2 The clinical result was that thoracotomy and lung resections for contusion and hemorrhage increased after lung missile injury.3...