Is bispectral index monitoring useful to assess the quality of analgesia in patients under general anesthesia?

Induction of general anesthesia and laryngoscopy with and without remifentanil: can bispectral index predict and/or detect the lack of analgesia?

Status

Not yet recruiting

Phases

Unknown

Study type

Interventional

Source

ANZCTR

Registry ID

ACTRN12614000487617

Enrollment

Registered

2014-05-09

Start date

2014-05-12

Completion date

Unknown

Last updated

2020-01-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

None listed

Brief summary

Bispectral index is a device used to monitor depth of anesthesia. Studies showed that it was well correlated with hypnotics, especially when used alone. Some data suggest that it can detect lack of analgesia. Our primary purpose was to test the ability of bispectral index to detect and/or predict the quality of analgesia.

Interventions

- Patients were randomized in 2 groups. - Group P: induction of anesthesia performed by propofol alone. - Group PR: induction of anesthesia performed by propofol and remifentanil. - Propofol administration was performed in the 2 groups by target-controlled infusion (TCI) using Schnider model. We targeted a plasmatic concentration of 6ug/ml obtained over 2 minutes. - Remifentanil administration was performed in the PR group by TCI using Minto model. We targeted a cerebral concentration of 4ng/ml. - We noted the arterial pressure, heart rate and bispectral index (BIS) each minute. - As BIS reached 60, consumption and cerebral concentration of propofol and time elapsed since the initiation of the induction were noted. Then, we fixed the plasmatic concentration of propofol to the cerebral concentration noted. - A muscle relaxing agent was administered and a laryngoscopy with endotracheal intubation was performed. - BIS, heart rate and arterial pressure were noted before and in the 2 minutes following laryngoscopy.

Study design

Allocation

Randomised controlled trial

Intervention model

Parallel

Primary purpose

Diagnosis

Masking

Open (masking not used)

Eligibility

Sex/Gender

All

Age

18 Years to 70 Years

Healthy volunteers

Inclusion criteria

- ASA class 1 or 2. - Proposed for elective surgery.

Exclusion criteria

- Predicted difficult intubation. - Hard-to-control hypertension. - Coronaropathy.

Outcome results