COPD患者肺叶切除术时低潮气量通气的效果

目的 评价慢性阻塞性肺疾病(COPD)患者行肺叶切除术时低潮气量通气的效果.方法 择期行肺叶切除术的COPD患者28例,年龄65～84岁,ASA Ⅱ或Ⅲ级,随机分为常规潮气量组(TV组,n=14)和低潮气量组(LV组,n=14).均于气管插管后行机械通气,参数设置:TV组潮气量(VT)为10 ml/kg,呼气末正压(PEEP)为0;LV组Vr为5～6 ml/kg,PEEP为0～5 cm H2O.采用旁气流法监测气道峰压(Ppeak)、气道平台压(Pplat)、气道阻力(Raw)及动态肺顺应性(Cd).于平卧位双肺通气10 min(T1)、侧卧位单肺通气90 min(T2)、术毕平卧位双肺通气10 min(T3)及术后24 h(T4)时取桡动脉血样,行血气分析,计算氧合指数(OI)、肺泡.动脉血氧分压差P(A-a)O2]及呼吸指数(RI);取颈内静脉血样,测定血清肿瘤坏死因子-α(TNF-α)及白细胞介素-6(IL-6)的浓度.结果 与T1时比较,2组T2-4时血清TNF-α及IL-6浓度升高(P<0.05);与TV组比较,LV组T2-4时血清TNF-α及IL-6浓度降低(P<0.05),T1-3时Ppeak及Raw降低,T2.3时Cd升高(P<0.05).T1-4时2组OI、RI及P(A-a)O2差异无统计学意义(P0.05).结论 低VT,通气可通过降低炎性反应,减轻COPD患者肺叶切除术时机械通气诱发的肺损伤.

Effects of mechanical ventilation with lower tidal volume on lung function in COPD patients undergoing lobectomy

Objective To investigate the effects of mechanical ventilation with lower tidal volume in patients with chronic obstructive pulmonary disease (COPD) undergoing elective lung resection. Methods Twenty-eight ASA II or m patients with COPD aged 65-84 yr undergoing elective lung resection were randomly divided into 2 groups (n=14 each):traditional tidal volume group (TV) and low tidal volume group (LV). The patients were premedicated with intramuscular atopinc 0.5 mg and phenobarbital 100 rag. Anesthesia was induced with midazolam, fentanyl and propofol. Vecuronium was used to facilitate insertion of double-lumen tube (DLT). Correct DLT position was confirmed by fiberoptic hronchoscopy. Anesthesia was maintained with continuous infusion of remifentanil, propofol and vccuronium and inhalation of 1%-2% sevoflurane. The patients were mechanically ventilated (I:E=1:2). Tidal volume (VT) was set at 10 ml/kg (PEEP=0) in group TV and at 5-6 ml/kg (PEEP =0-5 cm H2O) in group LV. Airway peak pressure (Ppeak), airway plateau pressure (Pplat), airway resistance (Raw) and dynamic lung compliance (Cd) were monitored by side stream spirometry. Arterial and venous blood samples were taken at 10 min of two-lung ventilation (TLV) in supine position (T1), at 90 min of one-lung ventilation (OLV) in lateral position (T2), at 10 min of two-lung ventilation in supine position after the end of operation (T3) and 24 h after operation (T4) for blood gas analysis and determination of serum concentrations of TNF-a and IL-6. PaO2/FiO2, P(A-a)O2 and P(A-a)O2/PaO2 were calculated. Results The serum concentrations of TNF-α and IL-6 were significantly increased at T2-4 as compared with the baseline at T1 in both groups. The serum concentrations of TNF-α and IL-6 at T2.4, Ppeak, Pplat and Raw at T1-3 were significantly lower and Cd at T2.3 was significantly higher in group LV than in group TV. There was no significant difference in PaO2/FiO2, P(A-a)O2 and P(A-a)O2/PaO2 at T1-4 between the 2 groups. Conclusion Mechanical ventilation with lower tidal volume can ameliorate the lung injury induced by mechanical ventilation through inhibition of inflammatory response in COPD patients undergoing lung resection.