[Abstract] Objective To explore the value of bedside ultrasound in monitoring peak flow velocity of abdominal aorta and its branches in assessing the volume status of patients with septic shock.Methods A total of 80 patients with septic shock admitted to the Foshan Rehabilitation Hospital(The Fifth People's Hospital of Foshan) and the Guangdong Provincial People's Hospital from June 2022 to June 2023 were selected as the research subjects. All patients were treated with mechanical ventilation,and deep venous catheters were placed in the internal jugular vein or subclavian vein to monitor central venous pressure (CVP).PiCCO catheters were placed in the femoral artery to monitor hemodynamic data.At the same time,the maximum internal diameter of the inferior vena cava (IVCmax),the respiratory variation of the inferior vena cava (△IVC),the peak flow velocity of the abdominal aorta (VpeakAA),the peak flow velocity of the celiac artery (VpeakCA),and the peak flow velocity of the superior mesenteric artery (VpeakSMA)were monitored under bedside ultrasound.The global end-diastolic volumn index(GEDI)was used as a grouping indicator,with GEDI≤680ml/m2 as the low-volume group and GEDI≥800ml/m2 as the high-volume group.Compare the differences in peak flow velocity between the abdominal aorta,celiac artery,and superior mesenteric artery between the two groups,and analyze the correlation between peak flow velocity of the abdominal aorta,celiac artery,and superior mesenteric artery and IVCmax,ΔIVC,CVP,and stroke volume variability (SVV);draw a receiver operating characteristic (ROC) curve for the subjects,calculate the area under the curve,and find the diagnostic threshold.Results There was no significant difference in general data between the two groups (P>0.05).The VpeakAA,VpeakCA,and VpeakSMA in the high-volume group were all higher than those in the low-volume group, and the differences were statistically significant (P<0.05). However,VpeakCA and VpeakSMA were significantly correlated with IVCmax,△IVC,CVP,and SVV (P<0.05).The ROC curve analysis showed that VpeakAA,VpeakCA,and VpeakSMA could effectively evaluate the volume status of patients with septic shock, and the area under the VpeakSMA curve was 0.846,with a 95% confidence interval of 0.693-0.999,and had high sensitivity and specificity.Conclusion Bedside ultrasound can dynamically monitor VpeakAA,VpeakCA,and VpeakSMA,which has great value in the evaluation of volume status in patients with septic shock.

The authors have declared no competing interest.

This study did not receive any funding

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The study was approved by the Ethics Committee of Foshan Fifth People's Hospital[2022](No. 0610).The approval date was July 6th, 2022.

I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.

Yes

I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

Yes

I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.

Yes

All data produced in the present work are contained in the manuscript