Cardiopulmonary dysfunction during minimally invasive thoraco-lumboendoscopic spine surgery

The endoscopic retroperitoneal approach to thoracolumbar anterior spine fus ion is associated with CO, insufflation into the thoracic space. We studied the cardiopulmonary effects of this CO2 thoraco-retroperitoneal insufflati on compared with the conventional open surgical procedure using thoraco-phr eno-lumbotomy in 12 pigs under balanced anesthesia, paralysis, and mechanic al ventilation. During open surgery of the thoracolumbar spine, animals exh ibited unchanged systemic and pulmonary hemodynamics, as well as ventilatio n and oxygenation variables. Animals retroperitoneally insufflated with CO, (12 mm Hg) exhibited a significant increase of Paco(2) and a moderate decr ease of PaO2, SaO(2), and pH, with insignificant changes of central venous filling pressures and systemic hemodynamics. Endoscopic phrenotomy with tho racic CO2 insufflation instantaneously and drastically affected hemodynamic status and pulmonary gas exchange with marked hypoxia, hypercapnia, system ic hypotension, tachycardia, and pulmonary hypertension within minutes. An increase of minute ventilation, inspiratory oxygen fraction, and positive e nd-expiratory pressure promptly reversed these cardiopulmonary effects. CO2 evacuation allowed the animals to completely recover and regain almost bas eline cardiopulmonary status, except for a reduced arterial blood pressure. Appropriate monitoring and immediate CO2 desufflation may be beneficial in cases of therapy-resistent hemodynamic, oxygenation, and ventilation diffi culties. Implications: For endoscopic thoraco-lumbar spine fusion, CO2 thor aco-retroperitoneum-induced cardiopulmonary dysfunction must be of: concern , especially in patients with cardiopulmonary compromise. Appropriate monit oring and immediate CO2 desufflation may be beneficial in cases of therapy- resistant hemodynamic, oxygenation, and ventilation difficulties.