Abstract:Objective: To analyze the characteristics and trends of hemodynamic changes in acute stage of paraquat poisoning,clarify the relationship between hemodynamic changes and prognosis,and provide clinical basis for cardiopulmonary bypass support.Methods: PQ poisoning patients older than 12 years old and poisoning time less than 24 hours admitted to the intensive care department of our hospital from January 1,2016 to December 31,2017 were selected as the observation objects.The patients were divided into early death group and early survival group according to whether the patients survived within 72 hours after poisoning.All patients took the same treatment strategy.The hemodynamic changes of the two groups were compared and analyzed.Results: The early survival group mainly suffered from moderate and severe poisoning,most patients died of respiratory failure;the early death group mainly suffered from fulminant poisoning,and most patients died of circulatory failure.Compared with the early death group,the early survival group had less toxicity,lower serum PQ concentration,lower SIPP score and lower serum lactic acid level (P<0.01);the early death group had higher initial serum creatinine than the survival group (P<0.05).However,there was no significant difference between the two groups in the time from poisoning to perfusion and from poisoning to the first blood purification (P>0.05).There was no significant difference in initial WBC,RBC,PLT,PH,PO2,PCO2,OI,SBC,CKMB,CTnI,NT-proBNP ,ALT,AST and TBIL (P>0.05).Cardiac output (CO),stroke output (SV),peripheral vascular resistance index (SVRI),heart rate (HR),systolic blood pressure (SBP),diastolic blood pressure (DBP) in the early death group showed a progressive downward trend,with significant difference between the two groups (P<0.01);central venous pressure (CVP) in the early death group showed a progressive upward trend,with two groups changing.There was a significant difference in the trend of change (P<0.01);the volume of thoracic fluid (TFC) in early death group and early survival group showed a gradual upward trend,with no significant difference (P>0.05).Conclusion: The patients with PQ poisoning with high dose of poisoning may have "low-output and low-resistance"hemodynamic changes in acute phase,which are characterized by decreased cardiac output and decreased peripheral vascular resistance,leading to circulatory failure.Hemodynamic monitoring should be carried out as soon as possible,the use of vasoactive drugs should be adjusted according to the changes of hemodynamics,or cardiopulmonary bypass support should be implemented as soon as possible to improve organ perfusion.In order to prolong the survival time of patients and improve the rescue success rate of patients with severe and fulminant PQ poisoning.