Prediction of the Effect of Fluid Administration Using Arterial Pressure and Ventilator Data During Abdominal Surgery

NCT04298931 | Completed

• 1 other identifier: 1-10-72-245-19
• Study Type: observational
• Target: 52
• Locations: 1 country
• Sites: 1

Brief Summary

It is well known, that patients with circulatory impairment sometimes, but not always, benefit from intravenous fluids. Predicting if a fluid administration will improve circulation is therefore of substantial clinical interest. Ventilator treatment induces cyclic variation in blood pressure due to interaction between the lungs and the heart. This variation is minor, but its amplitude may be used for guiding fluid administration. However, this method of using ventilator-induced variation in blood pressure to predict the effect of fluid administration was developed when different settings for ventilator treatment was recommended, compared with today. With today's recommend ventilator treatment, the method is, unfortunately, less reliable. The investigators will investigate how different ventilator settings influence variation in blood pressure, and the investigators will test if this knowledge allows us to better predict the effect of a fluid administration, by taking the ventilator settings into account.

Conditions

Hypovolemia; Fluid Overload

Outcome Measures

Primary Outcomes (1)

• >10% Increase in stroke volume from before to after a fluid bolus. (Fluid responsiveness)

  A patient is considered a fluid responder if they have a \>10% increase in stroke volume (pulse contour analysis by the Edwards EV1000 with a FloTrac sensor). Pre-fluid stroke volume is calculated as the median stroke volume estimate in the two minutes immediately preceding the fluid bolus. Post-fluid stroke volume is calculated as the median stroke volume estimate in the two minutes immediately following the fluid bolus. Change in stroke volume is calculated as: 100% \* (Post-fluid stroke volume - Pre-fluid stroke volume) / Pre-fluid stroke volume

  From two minutes before to two minutes after a fluid administration.

Study Arms (1)

Patients undergoing open abdominal surgery

Other: Series of ventilator settings

Interventions

Series of ventilator settings OTHER

Before a planned fluid administration, the investigators will apply a series of 10 ventilator settings for 30 seconds each. The settings are the following combinations of respiratory rate (RR) and tidal volume (TV): RR (min\^-1), TV (ml/kg predicted body weight) 31, 6 31, 8 24, 6 24, 8 17, 6 17, 8 10, 4 10, 6 10, 8 10, 10 (the order of the respiratory rates: 17 to 31, will be randomized. 10/min will always be last. Tidal volume is always applied from lowest to highest for each respiratory rate).

Patients undergoing open abdominal surgery

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

Patients at department of abdominal surgery, Aarhus University Hospital, scheduled for open abdominal surgery with planned use of Aarhus University Hospital's goal-directed therapy protocol (hemodynamic monitoring).

You may qualify if:

• Scheduled open abdominal surgery.
• Scheduled treatment with Aarhus University Hospital's goal-directed therapy protocol (hemodynamic monitoring).

You may not qualify if:

• Left ventricular ejection fraction ≤ 40 %
• Irregular heart rhythm (e.g. atrial fibrillation or frequent ectopic beats)
• Known right ventricular dysfunction (if reported qualitatively in pre-operative assessment or objectively via Tricuspid Annular Plane Systolic Excursion (TAPSE) \< 17 mm)
• Pregnancy
• Prior participation in this study

Sponsors & Collaborators

• University of Aarhus: lead
• Aarhus University Hospital: collaborator

Study Sites (1)

Aarhus University Hospital

Aarhus N, 8200, Denmark

Location

Related Publications (1)

• Enevoldsen J, Brandsborg B, Juhl-Olsen P, Rees SE, Thaysen HV, Scheeren TWL, Vistisen ST. The effects of respiratory rate and tidal volume on pulse pressure variation in healthy lungs-a generalized additive model approach may help overcome limitations. J Clin Monit Comput. 2024 Feb;38(1):57-67. doi: 10.1007/s10877-023-01090-6. Epub 2023 Nov 16.

  PMID: 37968547 DERIVED

MeSH Terms

Conditions

Hypovolemia; Edema

Condition Hierarchy (Ancestors)

Pathologic Processes; Pathological Conditions, Signs and Symptoms; Signs and Symptoms

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: March 2, 2020
• First Posted: March 6, 2020
• Study Start: May 15, 2020
• Primary Completion: June 29, 2021
• Study Completion: June 29, 2021
• Last Updated: July 16, 2021

Record last verified: 2021-04

Locations

DK (1)