Vasopressin is a non-catecholamine agent that induces vasoconstriction via V1 receptors. It is currently regarded as a second-line vasopressor in the treatment of septic shock. According to the Surviving Sepsis Campaign Guidelines for the Management of Sepsis and Septic Shock in Adults,vasopressin is recommended when norepinephrine doses reach 0.25–0.50 μg/（kg·min）and normal blood pressure cannot be maintained. However,hemodynamic alterations in pediatric septic shock differ significantly from those observed in adults,and there is currently insufficient evidence to support the use of vasopressin in pediatric septic shock. This review,in conjunction with recent clinical research data,explored the optimal timing of initiation,methods of administration,and clinical evaluation criteria for vasopressin in septic shock,aiming to provide valuable references for the optimization of septic shock management.

Hemodynamic monitoring in shock is one of the core challenges in sepsis management.This article systematically explores how to optimize hemodynamic management in septic shock from three perspectives:assessment of fluid responsiveness and tolerance,monitoring of arterial and venous blood pressure,and macro- and microcirculatory monitoring.Firstly,fluid responsiveness assessment is the foundation of fluid therapy,but it must be combined with fluid tolerance to avoid fluid overload.Secondly,the refined evaluation of arterial and venous pressure changes,from macrocirculation to microcirculation,provides a more comprehensive perspective for hemodynamic management.Thirdly,the transition from cardiac output to microcirculatory flow is critical for optimizing oxygen delivery,requiring dynamic adjustment of treatment through both invasive and non-invasive techniques,while also considering the relationship between cardiac output and oxygen delivery and their impact on tissue oxygenation.By integrating these monitoring approaches,individualized and precise treatment for septic shock patients can be achieved,thereby improving outcomes.

Septic shock,a life-threatening subset of sepsis characterized by profound cardiovascular dysfunction,remains a leading contributor to global morbidity and mortality.Early identification and warning are critical to reducing septic shock-related mortality.This article reviewed the definition,diagnostic criteria,early clinical manifestations,and biomarkers of septic shock,providing reference for early diagnosis of septic shock and clinical basis for improving patient prognosis.

Pediatric severe pneumonia is characterized by an abrupt onset and swift progression，frequently complicated by serious complications，which is the leading cause of death in children under 5 years old. In recent years，the prevalence of gram-negative bacterial infections in severe pneumonia patients has been on the rise，and the inappropriate use of antibiotics has augmented the resistance of bacteria，thereby complicating their treatment. Therefore，early diagnosis and timely treatment are particularly critical. This review provided the common gram-negative bacteria，risk factors and triggers，microbiological testing methods，resistance mechanism，and treatment in children with severe pneumonia，with the aim of providing clinically useful guidance for pediatricians when treating such patients.

The initial fluid resuscitation strategies for septic shock are determined based on the availability of intensive care facilities.Balanced/buffered crystalloids are the preferred choice for the initial resuscitation of children with septic shock.The principles of volume management,known as SRT(State,Responsiveness,Tolerance),optimize fluid management and avoid fluid overload.Early initiation of vasoactive agents during resuscitation can offer multiple benefits,with epinephrine and norepinephrine serving as the first-line vasoactive infusions.The ROSE(Resuscitation,Optimization,Stabilization,Evacuation) conceptual model summarizes accurately a dynamic approach to fluid therapy,maximizing benefits and minimizing harms.Point-of-care critical ultrasound combined with other hemodynamic monitoring parameters offers the possibility of individualized treatment of children with septic shock.

Critically ill with capillary leakage syndrome（CLS）presents with damaged vascular endothelial cells with glycocalyx degraded,which increases vascular permeability,and leads to the protein-rich fluid from the intravascular extravasate into the interstitial space.CLS can concomitant symptoms of hypovolemia and fluid overload.Fluid therapy is the most critical element in the treatment of CLS,but still lack of sufficient evidence to guide the choice of fluid management.Based on accurately hemodynamic monitoring,balanced salt or crystalloid + albumin or fresh frozen plasma may be input to ensure effective circulating blood volume.Albumin or fresh frozen plasma is particularly suitable for CLS patients failed to respond to crystalloids during the leakage period.In the later stage of leakage,conservative fluid management with “de-resuscitation”strategy was mainly used with diuretic and hemofiltration (renal replacement therapy/continuous renal replacement therapy) for attenuating fluid overload.Steroids and ulinastatin may be effective in CLS caused by sepsis.

Hemorrhage is the primary early clinical manifestation in pediatric trauma patients and is the main cause of hypovolemic shock.The goal of fluid resuscitation is to optimize perfusion to terminal organs and provide adequate oxygen supply.During the resuscitation process,it is important to follow damage control surgery and damage control resuscitation protocols to prevent hypotension.It is recommended to administer low titer group O whole blood or component blood early in the resuscitation process,while minimizing the use of large volumes of crystalloid fluids.Continuous monitoring of the child’s condition is necessary during resuscitation,with particular attention to vital signs,laboratory tests,and imaging studies.Bedside ultrasound can quickly assess the injury site and changes in hemodynamics during resuscitation,providing a basis for precise individualized treatment.

Pneumonia complicated by diarrhea in children is a common clinical phenomenon.During fluid resuscitation,it is essential to prevent fluid deficiency while avoiding excessive fluid administration,which can lead to pulmonary interstitial edema or heart failure.A conservative fluid resuscitation strategy is recommended,initially utilizing a balanced crystalloid solution for resuscitation.If a significant volume of fluid is still required after assessment,colloid solutions may be considered.In accordance with the ROSE strategy for fluid resuscitation in sepsis,a staged fluid management approach should be implemented for children with pneumonia and diarrhea.Continuous monitoring of the patient's response to resuscitation and the improvement of clinical symptoms is crucial.If feasible,advanced hemodynamic monitoring should be employed.It is advisable to utilize multiple parameters and diverse methods to comprehensively assess the patient's clinical condition,thereby enabling the formulation of individualized fluid management plans.

Objective:To summarize the clinical symptoms of cyclic vomiting syndrome（CVS）in children and investigate its association with small intestinal bacterial overgrowth（SIBO）.Methods:A total of 89 children who were diagnosed as CVS and improved lactulose hydrogen breath test (LHBT) in the Pediatric Department of Beijing Tsinghua Changgung Hospital from June 2020 to June 2023 were selected as CVS group.Simultaneously，50 healthy children with physical examination in our hospital were selected as the control group. According to the results of LHBT,the children with CVS were divided into SIBO group (LHBT positive) and non-SIBO group (LHBT negative). The clinical data of children in each group were compared.Results:Among the 89 CVS patients，there were 42 males and 47 females，with a mean age of（7.50±3.54）years.Common accompanying symptoms included excessive sleepiness（76 cases，85.39%），anorexia(62 cases，69.66%），constipation（55 cases，61.80%），abdominal pain（34 cases,38.20%）and so on. There were no significant differences in age and gender between children in CVS group and control group ( P>0.05). The body mass index of CVS group was lower than that of control group.The positive rate of LHBT was higher than that of the control group (56.18% vs. 8.00%),the difference was statistically significant ( P<0.05),and the concentrations of hydrogen and methane in CVS group were higher than those of the control group at different time points( P<0.05).Among 89 children with CVS,there were 50 cases in SIBO group and 39 cases in non-SIBO group. There were no significant differences in gender,age and body mass index between the two groups ( P>0.05). The constipation rate and moderate/severe disease rate in SIBO group were higher than those in non-SIBO group (88.00% vs. 28.21%,94.00% vs. 43.59%),and the differences were statistically significant ( P<0.05). Conclusion:The incidence of SIBO in children with CVS is higher,and SIBO may play a key role in CVS. CVS children with SIBO have higher disease severity.

Objective:To analyze and summarize the clinical features and short-medium term follow-up results of children with multisystem inflammatory syndrome（MIS-C）following coronavirus infection.Methods:The data of six children with MIS-C admitted to the Intensive Care Unit of Shanghai Children's Medical Center from January to March 2023 were retrospectively analyzed.Results:All six cases were in shock，requiring vasoactive drugs，and one case required invasive mechanical ventilation.All the six patients had multiple organ function injury and increased inflammation indicators.After admission，they received organ support，glucocorticoids and gamma globulin treatment.Two patients were treated with biological agents.Both organ function and inflammation indicators showed significantly improvement after therapy.Six patients had mild coronary artery widening.All patients had good prognosis following short-medium term follow-up.Conclusion:Children with severe MIS-C may suffer life-threatening hemodynamic instability.Timely assessment，active anti-inflammatory and organ support therapy can obtain favorable prognosis.