Influence of Variations of Systemic Venous Return on Analgesia Nociception Index (ANI) During General Anaesthesia

University Hospital, Lille

Status: Completed

Conditions: Hypovolemia; Somatic Pain

Treatments: Procedure: change in operating table slope: head-down tilt position; Procedure: change in operating table slope: head-up tilt position; Procedure: noxious stimulus

Study type: Interventional

Funder types: Other

Identifiers

NCT02193412

2013_13

2013-A01645-40 (Other Identifier)

Details and patient eligibility

About

The purpose of this study is to determine whether the value of analgesia nociception index (ANI) is influenced by variations of systemic venous return (cardiac preload) under general anaesthesia.

Full description

In the context of opioid sparing goal during general anaesthesia, the Analgesia nociception index (ANI) is an analgesia/nociception balance monitoring tool computed from high frequency heart rate variability analysis, and developed by MetroDoloris (Lille, France). Its sensitivity to detect noxious stimulus was studied in several studies. However, its specificity is not established in particular in the presence of factors influencing autonomic nervous system other than analgesia/nociception balance. In the context of anaesthesia, one of the most relevant factor is hypovolemia. This study aims to assess the effect of blood volume variations on ANI under general anaesthesia, independently of analgesia/nociception balance status. Variations of systemic venous return (SVR) (cardiac preload), which reflects blood volume status, will be induced by changes of operating table slope, from head-down tilt (Trendelenburg), with increased SVR, to head-up tilt position, with decreased SVR. Variations of SVR will be attested by changes in the arterial pulse pressure variation, a well-established indice of preload responsiveness in the mechanically ventilated anaesthetized patient.

Enrollment: 30 patients

Sex: All

Ages: 18 to 70 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• neurosurgical operation requiring invasive monitoring of arterial blood pressure

Exclusion criteria

• pacemaker, arrhythmia
• chronic medication with beta blocker
• possible disorder of autonomic nervous system: diabetes, alcoholism, chronic pain
• anticholinergic drug administration before measures
• intracranial hypertension
• no social security coverage
• pregnancy

Trial design

Primary purpose: Diagnostic

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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30 participants in 1 patient group

patients

Experimental group

Description:

1. noxious stimulus 2. change in operating table slope: head-down tilt position 3. change in operating table slope: head-up tilt position

Treatment:

Procedure: noxious stimulus

Procedure: change in operating table slope: head-up tilt position

Procedure: change in operating table slope: head-down tilt position