Sofi Khalid, Wani Tariq
Staff Physician, Department of Anesthesia, King Abdul-Aziz Medical City, King Fahad National Guard Hospital, Riyadh, Columbia, Missouri, USA.
Saudi J Anaesth. 2010 Jan;4(1):2-5. doi: 10.4103/1658-354X.62606.
This study was undertaken to find out the effect of early tracheostomy on weaning from mechanical ventilation. Pulmonary mechanics and arterial blood gases were assessed before and after tracheostomy in patients with severe head injury (Glasgow coma score < 8) requiring prolonged mechanical ventilation.
The study included 20 mechanically ventilated patients of either sex between 20 and 45 years of age, who had suffered brain injury due to head trauma during admission (Glasgow coma scores of < 8). Mean airway pressure, peak airway pressure, plateau pressure, PaO(2) and PaCO(2) were measured 24 h before and after tracheostomy. Static and dynamic compliances were calculated.
Plateau airway pressures were not affected by tracheostomy, but peak airway pressure was reduced (29.90 +/- 3.21 cm H(2)O before tracheostomy versus 24.30 +/- 1.83 cm H(2)O after tracheostomy, P < 0.001). Dynamic compliance, but not static compliance, was improved by tracheostomy. Tracheostomy did not affect PaCO(2), but it improved PaO(2) (83.09 +/- 5.99 mmHg before versus 90.84 +/- 5.61 mmHg after, P < 0.001).
The work of breathing through a tracheostomy tube may be less than through an endotracheal tube of same internal diameter.
本研究旨在探讨早期气管切开术对机械通气撤机的影响。对需要长期机械通气的重度颅脑损伤患者（格拉斯哥昏迷评分＜8分）在气管切开术前和术后评估肺力学和动脉血气。
本研究纳入20例年龄在20至45岁之间、因入院时头部外伤导致脑损伤（格拉斯哥昏迷评分＜8分）的机械通气患者，男女不限。在气管切开术前和术后24小时测量平均气道压、气道峰压、平台压、PaO₂和PaCO₂，并计算静态和动态顺应性。
气管切开术未影响平台气道压，但气道峰压降低（气管切开术前为29.90±3.21cmH₂O，术后为24.30±1.83cmH₂O，P＜0.001）。气管切开术改善了动态顺应性，但未改善静态顺应性。气管切开术对PaCO₂无影响，但改善了PaO₂（术前为83.09±5.99mmHg，术后为90.84±5.61mmHg，P＜0.001）。
通过气管切开套管进行呼吸的工作量可能小于通过相同内径气管内导管进行呼吸的工作量。
