Etiology And Risk Factors Of Septic Shock In Preterm Infants With Late Onset Sepsis

Objective: To understand the etiology,clinical features and outcome of septic shock in premature infants with late sepsis,and to explore the risk fators of septic shock in premature infants.Methods: Retrospective analysis: from January 2011 to December 2016,premature infants were admitted to the second neonatal department of shengjing hospital affiliated to China medical university and diagnosed with late sepsis and septic shock(shock group);premature infants without septic shock and late sepsis who were hospitalized at the same time were used as the control group(non-shock group).Except for shock caused by other reasons(cardiogenic shock,hypovolemic shock),various congenital malformations and abandoned treatment after diagnosis.The clinical data of premature infants in the two groups were compared to understand the clinical features and outcomes of septic shock caused by different pathogens,and the risk factors of septic shock in premature infants were discussed through multi-factor regression analysis.Result:There were 234 premature infants with sepsis,54(23.1%)in the shock group(male/female 1.45/1).Gestational age was 23-36 w,with an average of30.29±2.06 w.Birth weight was 440-1690 g,with an average of 1290±488g.40 survivors(74.1%)and14 deaths(25.9%).The mean gestational age of the survivors(28.98±2.21w)was significantly higher than that of the mortality(26.83±2.21w).The 180 cases(76.9%)in the non-shock group(male/female 1.54/1).Gestational age was 23-36 w,with an average of 32.22±2.14 w,and birth weight was 480g-3620 g,with an average of1374±490g,168 survivors(93.3%)and 12 deaths(6.7%).Gestational age ?28w,birth weight < 1000 g,premature rupture of membranes ratio(38.9%,44.4%,35.9%)in the shock group was significantly higher than that in the non-shock group(20.6%,23.9%,18.3%),P < 0.05.In the shock group,the mean corrected gestational age was34.21±2.93 d,mean blood lactic acid was 4.53±1.51mmol/L,respiratory support time was 79.63% and 87.04%,hospital stay was 56.67±27.94 d,and the infection rate of gram-negative bacteria was(72.2% vs48.9%),case fatality rate(25.9%)wassignificantly higher than that of the non-shock group(33.57±23.5d,3.77±1.16mmol/L,58.3%,49.4%,47.01±23.57 d,6.7%),P<0.05.The mean lactic acid level in the death group(8.24±4.57mmol/L)was significantly higher than that in the survival group(6.26±3.25mmol/L).,and Metabolic acidosis(-8.06±2.66mmol/L)was significantly worse than that of the survival group(-6.46±2.12mmol/L).(P < 0.05).Gestational age ?28 weeks and gram-negative bacterial infection were risk factors for septic shock in premature infants with late sepsis.Gestational age ?28 weeks,birth weight < 1000 g,blood lactate > 4.8mmol/L were predictors of premature infant death from septic shock.Conclusion:1.Gram-negative bacteria are the main cause of septic shock in premature infants with sepsis2.Septic shck increased the complications of premature infants;3.Gestational age ?28w and gram-negative bacterial infection were the risk factors of infection shock in premature infants.Gestational age ?28 weeks,birth weight < 1000 g,and increased blood lactic acid were predictors of death from septic shock.