Effect of Pressure-Controlled Ventilation-Volume Guaranteed on Pulmonary Oxygenation Function in Patients Undergoing...

Objective To evaluate the effect of pressure-controlled ventilation-volume guaranteed(PCV-VG)on the perioperative pulmonary oxygenation function of the patients undergoing off-pump coronary artery bypass grafting(OPCABG). Methods Forty patients aged 40-65 years,of both sexes,with the American Society of Anesthesiologists physical status Ⅲ or Ⅳ,preoperative cardiac function(NYHA)class Ⅱ or Ⅲ,scheduled for elective OPCABG were assigned via the random number table method into two groups(n=20):a volume-controlled ventilation(VCV)group(Group V)and a PCV-VG group(Group P).Other respiratory parameters of the anesthesia machine were set consistently in both groups.At the time of sawing the sternum(T₀),when left internal mammary artery harvesting with the operating table tilted 10° to the left(T₁),when left anterior descending coronary artery bypass grafting with the operating table tilted 10° to the right(T₂),when right coronary artery bypass grafting with the operating table in a 30° head-down and tilted 10° to the right(T₃),when circumflex coronary artery bypass grafting with the operating table in a 20° head-down and tilted 15° to the right(T₄),and at the end of the surgery(T₅),the peak airway pressure(Ppeak),mean airway pressure(Pmean),plateau airway pressure(Pplat),and pulmonary dynamic compliance(Cdyn)were recorded.The alveolar-arterial partial pressure difference of oxygen(PA-aDO₂),oxygenation index(OI),and respiratory index(RI)were recorded at the aforementioned time points as well as on postoperative day 1(T₆),day 3(T₇),and day 7(T₈).The dosages of intraoperative drugs(sufentanil,remifentanil,and rocuronium bromide),postoperative endotracheal tube indwelling time,the stay time in the cardiac surgery intensive care unit,and the occurrence of pulmonary complications within 7 days after the surgery were also recorded. Results Compared with Group V,Group P showed significant downward trends in Ppeak,Pmean,and Pplat during T₃-T₅,as well as in PA-aDO₂ and RI during T₃-T₈(all P<0.05).Meanwhile,Group P exhibited significant upward trends in Cdyn during T₃-T₅ and in OI during T₃-T₈(all P <0.05).Compared with those in Group V,the postoperative endotracheal tube indwelling time and the stay time in the cardiac surgery intensive care unit were shortened in Group P(all P<0.05).There was no statistically significant difference in dosages of intraoperative drugs(sufentanil,remifentanil,and rocuronium bromide)or incidence of pulmonary complications within 7 days after the surgery between the two groups of patients(all P>0.05). Conclusion Compared with VCV,PCV-VG can improve the perioperative pulmonary oxygenation function of the patients undergoing OPCABG.