Surrogate of Adequate Perfusion: Bladder Tissue Oxygen Monitoring

Surgery Clinical Trial

— SoAP-BOx  

Official title:

An Observational Study of Tissue Oxygen Monitoring for Detecting Impending Shock States in the Critically Ill and Those Undergoing High Risk Surgery

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT03935477
• Other study ID #: CIP_DPW016_OBS
• Status: Recruiting
• Start date: April 10, 2019
• Est. completion date: March 2020

Study information

• Verified date: May 2019
• Source: University College London Hospitals
• Contact: Mervyn Singer, MB BS
• Phone: +44-207-679-6714
• Email: m.singer[@]ucl.ac.uk
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

The extent and duration of tissue hypoxia is a major determinant of outcome following major, high-risk surgery and in critical illness. Prompt restoration of tissue oxygenation through resuscitation in all likelihood improves outcomes. There are currently no bedside monitors in clinical practice that track tissue perfusion per se, instead clinicians rely on crude surrogates such as heart rate and blood pressure, urine output, serum lactate of global flow (cardiac output) monitoring.

This is a first-in-man trial of a new device to measure tissue oxygenation in real time in a major, high-risk surgical and critical care cohort. The device consists of an oxygen sensing probe incorporated into a modified urinary catheter, which relies on photoluminescence technology and the quenching properties of oxygen.

Once inserted, the drained bladder collapses round and envelopes the probe which continuously measures tissue oxygenation of the bladder urothelium.

The investigators hope to (i) Establish that tissue oxygenation can be safely monitored using this technology, deployed in this way. (ii) Define a normal range for bladder tissue oxygenation in man as measured using this device. (iii) Compare tissue oxygenation against other markers of perfusion status in current clinical practice and assess its performance at detecting inadequate perfusion against these other modalities. (iv) assess the diagnostic and prognostic capabilities of the tissue oxygenation monitoring at detecting hypo-perfusion and predicting outcome. (v) Further assess the tissue response to an 'oxygen challenge' in identifying occult hypo-perfusion. (vi). Provide pilot work required to inform future, interventional studies where similar patients would be resuscitated to tissue oxygenation targets alongside routine clinical practice.

Description:

As above

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 315
• Est. completion date: March 2020
• Est. primary completion date: February 2020
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• having major elective or emergency surgery (deemed to need invasive BP monitoring by anaesthetist) and a urinary catheter

• OR emergency admission to critical care (necessitating arterial line and urinary catheter).

Exclusion Criteria:

• age <18

• pregnancy

• contraindication to arterial cannulation or urethral catheterisation

• surgery on lower urinary tract/bladder

• patient refusal

Related Conditions & MeSH terms

• Sepsis
• Shock
• Surgery

Intervention

Device:
• WellBeing catheter
Urethral catheterisation with integral Wellbeing Catheter to measure bladder tissue oxygen tension

Locations

Country	Name	City	State
United Kingdom	UCL Hospitals NHS Foundation Trust	London

Sponsors (3)

Lead Sponsor	Collaborator
University College London Hospitals	Department of Health, United Kingdom, Wellcome Trust

Country where clinical trial is conducted

United Kingdom, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Time to identification of a low bladder tissue PO2 versus time to development of hyperlactatemia (2 mmol/l)	Comparison of bladder tissue PO2 values (normal range to be defined as part of this first-in-man study) against lactate values >2 mmol/l	Up to 7 days
Primary	Time to identification of a low bladder tissue PO2 versus time to development of hypotension (mean BP <60 mmHg)	Comparison of bladder tissue PO2 values (normal range to be defined as part of this first-in-man study) against mean BP values <60 mmHg	Up to 7 days
Secondary	Number of Participants With Device-Related Adverse Events	Monitoring of direct device-related complications (e.g. bleeding, bladder perforation)	Up to 28 days
Secondary	Identification of future complications in postoperative patients	Low bladder tissue PO2 values identify postoperative complications using POMS-score-defined morbidity at Days 3 and 7	Up to 7 days