Central venous oxygen levels (ScvO2) for fluid optimisation in high risk surgical patients

• Register: ISRCTN
• Last refreshed on: 17 October 2016
• Main ID: ISRCTN50142780
• Date of registration: 24/01/2012
• Prospective Registration: No
• Primary sponsor: James Cook University Hospital (UK)
• Public title: Central venous oxygen levels (ScvO2) for fluid optimisation in high risk surgical patients
• Scientific title: Can changes in central venous oxygen saturation and central venous - arterial partial pressure of carbon dioxide difference predict changes in stroke volume in high risk surgical patients?
• Date of first enrolment: 01/10/2010
• Target sample size: 25
• Recruitment status: Completed
• URL: http://isrctn.com/ISRCTN50142780
• Study type: Observational
• Study design: Single-centre clinical pilot study (Treatment)
• Phase: Not Applicable

Countries of recruitment

United Kingdom

Contacts

• Name: Jost Mullenheim

Key inclusion & exclusion criteria

Inclusion criteria: 1. Elective major open abdominal surgery (gastrointestinal, urological, gynaecological or vascular procedures with an expected duration of at least 90 minutes)
2. Requirement for invasive haemodynamic monitoring including arterial and central venous blood pressure and CO measurement
3. More than 50 years of age and at least one of the following:
3.1. Renal impairment (serum creatinine > 130 µmol/l)
3.2. Diabetes mellitus
3.3. Aged 65 years and over
3.4. Presence of a risk factor for cardiac or respiratory disease:
3.4.1. Exercise tolerance = 6 metabolic equivalents (MET?s)
3.4.2. Anaerobic threshold = 14 ml/kg/min
3.4.3. Past medical history of ischaemic heart disease
3.4.4. Heart failure
3.4.5. Moderate or severe valvular disease
3.4.6. Chronic obstructive pulmonary disease (COPD)
3.4.7. Radiographically confirmed chronic lung disease (COPD, fibrosis)
Exclusion criteria: 1. No consent
2. Pregnancy
3. Emergency surgery
4. Vascular surgery involving aortic cross clamping
5. Allergy to Gelofusin® and Volulyte®
6. Laparoscopic surgery

Age minimum:
Age maximum:
Gender: Both

Health Condition(s) or Problem(s) studied

Improving outcomes in high-risk surgical patients
Surgery

Intervention(s)

1. All patients enrolled in the study will receive standard anaesthetic care: after induction of anaesthesia with a hypnotic drug (propofol or thiopental) all patients will receive a balanced anaesthetic consisting of a volatile anaesthetic which is added to the inspiratory gas, muscle relaxant and opioid. An arterial and central venous catheter will be placed for monitoring of arterial and central venous blood pressure respectively. SV and hence CO will be monitored by connecting the existing arterial catheter to a LiDCO® monitor. Haemoglobin will be maintained > 8g/dl, SaO2 =94 %, heart rate < 100 bpm, mean arterial blood pressure 60-100 mmHg and temperature at 36-37º C. The ventilator will be set to achieve a pCO2 of 4.5-5.5 kPa. Postoperative analgesia will be provided via epidural or patient controlled analgesia. Similar to other intraoperative fluid optimisation studies SV and hence CO optimisation will be performed after induction of anaesthesia and placement of catheters.

To answer the proposed research question blood samples for blood gas analysis will be drawn simultaneously from the arterial and central venous catheter (2 ml each) in any patient in whom administration of a fluid bolus to increase SV and hence CO is planned. Three consecutive measurements of ScvO2, central venous and arterial pCO2 will be performed from the same blood sample and the average will be calculated and used for further statistical analysis. Immediately after any series of blood samples SV and hence CO will be recorded. Each fluid bolus will contain of 250 ml colloid (Gelofusin® or Volulyte®) i.v. given over 2 minutes. Another set of blood samples will be taken and SV and hence CO will be measured 5 minutes after the fluid bolus has been given. In each patient we will perform up to three consecutive serial measurements of SV and hence CO in response to a fluid bolus and, concurrently, the two surrogate variables SvcO2 and CVA-pCO2-diff. Thus, in each study participant we will t

Primary Outcome(s)

The correlation between changes of stroke volume and hence cardiac output with changes in central venous saturation and central venous arterial partial pressure of carbon dioxide difference, respectively

Secondary Outcome(s)

Sensitivity and specificity of pulse pressure and stroke volume variation and pleth variability index (PVI) to predict an increase of cardiac output by at least 10%

Secondary ID(s)

10/H0906/61

Source(s) of Monetary Support

James Cook University Hospital Trust (UK), NIHR Comprehensive Local Research Networks Flexibility and Sustainability Funding (UK)