Intraoperative Lung Protective Ventilation Reduces Postoperative Pulmonary Complications In Pediatric Living Related Liver Transplantation

Background Infants and young children undergoing living relatedliver transplantation (LRLT) have a high risk of postoperativelung complications.Lung-protective ventilation is consideredbest practice in the care of ARDS and many critically ill patients.However, its role in infants and young children undergoing LRLTis not known.Objective To determine whether a multifaceted strategy ofprophylactic lung protective ventilation that combined low tidalvolumes, PEEP, and recruitment maneuvers could reduce theincidence of early pulmonary complications and improve short-termprognosis after pediatric LRLT.Methods60children undergoing LRLT were randomized into3groupsaccording to the inclusion and exclusion criteria.Patients inconventional ventilation group (CV group) were ventilated with atidal volume of10to12ml per kilogram of body weight,with noPEEP or recruitment maneuvers during operation.Patients in high volume ventilation group (HV group) were ventilated with a tidalvolume of10to12ml per kilogram of body weight,with a PEEP of5cm of water and no recruitment maneuvers during operation.Patients in protective ventilation group (PV group) wereventilated with a tidal volume of6to8ml per kilogram of bodyweight,a PEEP of5cm of water,and recruitment maneuvers at thebeginning of new hepatic phase.The primary measurements were acomposite of major pulmonary complications occurring within thefirst7days after surgery and mortality within30days aftersurgery.The secondary outcomes were intraoperative static lungcompliance (Cst), airway resistance(Raw), oxygenation index(OI),respiratory index(RI), proportion of intrapulmonary shunt(Fshunt), pulmonary vascular permeability index(PVPI),extravascular lung water index(ELWI) and postoperative majorextrapulmonary complications,mechanical ventilation time,lengthof ICU stay and hospital stay.Results The57children included had similar characteristics atbaseline.34(59.6%)patients had major pulmonary complicationswithin7days after LRLT and29(50.9%)patients had grade Ⅲ-Ⅳ pulmonary complications. Of the34children,26(45.6%) were diagnosed ARDS and25(43.9%) were diagnosed pneumonia.Theincidence of major pulmonary complications in PV group was lowerthan that in CV group（OR [odds ratio],0.19;95%CI,0.05-0.77;P=0.02）and HV group （OR,0.22;95%CI,0.06-0.90; P=0.04）. Theincidence of severe pulmonary complications in PV group was alsolower than that in CV group （OR,0.15;95%CI,0.04-0.62; P=0.009）The incidence of ARDS （acute respiratory distress syndrome）inPV group was lower than that in CV group(OR,0.22;95%CI [confidenceinterval],0.05-0.90;P=0.04) and HV group （OR,0.17;95%CI,0.01-0.73; P=0.02）.No difference was found between three groupsin respect of mortality. Postoperative major extrapulmonarycomplications,length of ICU stay and hospital stay were similaramong three groups.Postoperative mechanical ventilation time inPV group was shorter than that in CV group (P=0.02).Analysis ofintraoperative measurements including Cst、Raw、OI、RI、Fshunt、PVPI and ELWI showed significantly improvement in PV group.Conclusions The use of lung protective ventilation strategy ininfants and young children undergoing LRLT was associated withimproved pulmonary edema and reduced pulmonary complication earlyafter surgery,which may improves the clinical outcomes of pediatric LRLT.