Effects Of A Preemptive Alveolar Recruitment Strategy On Arterial Oxygenation And Breathing Mechanics During Laparoscopic Radical Gastrectomy In Elderly Patients With Different Tidal Volumes

Objective: To investigate the effect of a preemptive alveolar recruitment strategy combined with lung protective ventilation on arterial oxygenation and breathing mechanics during selective laparoscopy-assisted radical gastrectomy in elderly patients.Methods: In total, 80 ASA I to III patients undergoing selective laparoscopy-assisted radical gastrectomy for gastric cancer, aged 65-79 yr,were randomized into four groups comprising 20 patients each: those administered a 8 ml/kg tidal volume with or without preemptive ARS(Group H and Group H-ARS, respectively) and those administered a 6 ml/kg tidal volume and a 5cm H2 O PEEP(positive end expiratory pressure) with or without preemptive ARS(Group L and Group L-ARS, respectively). To measure PETCO2, Ppeak, Pmean, and calculate the Cdyn, arterial blood gas at 10 min after intubation(T0), 10 min after ARS(T1), 10 min after the began of pneumoperitoneum(T2), 30 min after the began of pneumoperitoneum(T3), 10 min after the end of pneumoperitoneum(T4), respectively, and according to the Pa O2, Pa CO2, Fi O2 calculating oxygenation index, respiratory index, A-a DO2.Results: Preemptive ARS significantly improved the Pa O2/Fi O2 ratio compared to the groups that did not receive ARS(P<0.05). The H-ARS group showed a highest Pa O2/Fi O2 ratio during selective laparoscopy-assisted radical gastrectomy, the L-ARS and H groups showed similarly improved arterial oxygenation, which was significantly higher than in group L(P<0.05). The plateau airway pressure in group H-ARS was significantly higher than in group L-ARS(P<0.05).Conclusion: Preemptive ARS can improve arterial oxygenation during selective laparoscopy-assisted radical gastrectomy. Furthermore, a 6 ml/kg tidal volume combined with 5 cm H2 O PEEP after preemptive ARS may reduce the risk of pulmonary injury caused by high tidal volume during selective laparoscopy-assisted radical gastrectomy.