Completed

NCT Number: NCT02102139

Preop Dexmedetomidine Attenuates Haemodynamic Responses to Hydrodissection

Percutaneous tunnelling (hydrodissection) in the neck and anterior chest in patients undergoing robotic thyroidectomy leads to significant haemodynamic responses such as increases in blood pressure and heart rate. The investigators evaluated whether a single preoperative dexmedetomidine injection attenuated the haemodynamic responses to hydrodissection by reducing the half-maximal effective concentration (EC50) of remifentanil needed to maintain haemodynamic stability during hydrodissection.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Robotic Thyroidectomy

Age range

20 year–65 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 4

Primary location

Seoul National University of Hospital

Seoul, 110-799, South Korea

About this study

Dexmedetomidine (DXM) is a recently released and approved alpha 2 agonist with a relatively high ratio of α2/α1-activity and an almost fourfold shorter half-life than clonidine.It's sympatholytic, sedative, and analgesic properties makes DXM a useful anaesthetic adjuvant for general anaesthesia. While there are some reports of the beneficial effects of DXM on anaesthetic requirements and haemodynamic responses to endotracheal intubation, the effect of a single preoperative injection of DXM in terms of attenuating haemodymanic responses to surgical stimulation in robot-assisted thyroidectomy is unknown.

When a robotic thyroidectomy using the bilateral axillary breast approach (BABA) technique is performed, subcutaneous tunnelling in the neck and anterior chest, which is defined as hydrodissection, is mandatory. Unfortunately, the procedure leads to significant haemodynamic responses, such as increases in blood pressure and heart rate.

We hypothesised that preoperative DXM administration would attenuate the haemodynamic responses to hydrodissection. This study was designed to evaluate the effects of a single preoperative administration of DXM on haemodynamic responses to hydrodissection in robotic thyroidectomy by comparing the half-maximal effective concentration (EC50) of remifentanil needed to maintain haemodynamic stability during hydrodissection between DXM and control groups. We also investigated the effects of preoperative DXM administration on total doses of remifentanil and propofol administered intraoperatively.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

ASA physical status I-II patientsscheduled for general anaesthesia for robotic thyroidectomy

Exclusion criteria

Patients with an allergy to α2-adrenergic agonists or propofol
Patients with current antihypertensive medication
Patients with heart block > 1 degree
Patients with severe cardiorespiratory dysfunction
Patients with history of alcohol or drug abuse
Patients who had received an opioid analgesic medication within the previous 24-h period before the operation

Treatment and study plan

DXM + Propofol

Drug

After induction as mentioned at 'arm description', the effect-site propofol concentration was fixed at 5.0 μg mL-1 at the time of diluted epinephrine injection and was unchanged during the entire hydrodissection period in all patients.

The first patients received effect-site concentrations of remifentanil of 4 ng mL -1, respectively. The EC50 of remifentanil for stable hydrodissection was determined by a modification of Dixon's up-and-down method.If the response was "success (SBP during the entire hydrodissection period being ±20% from baseline)," the next target concentration of remifentanil was decreased by a step of 0.5 ng mL -1. If the response was "fail(SBP > ±20% from baseline)," the target concentration was increased by 0.5 ng mL-1.

Saline + Propofol

Drug

All procedure would be same in DXM+Propofol group except saline loading rather than DXM loading before induction.

Primary outcomes

Remifentanil EC50 during hydrodissection

Time frame: at the time point of hydrodissection intraopeartively

Compare remifentanil EC50 for maintaining haemodynamic stability during hydrodissection between 2 groups.

The EC50 of remifentanil for maintaining haemodynamic stability was determined by a modification of Dixon's up-and-down method.If the response was "success (SBP during the entire hydrodissection period being ±20% from baseline)," the next target concentration of remifentanil was decreased by a step of 0.5 ng mL -1. If the response was "fail(SBP > ±20% from baseline)," the target concentration was increased by 0.5 ng mL-1.

Secondary outcomes

Total doses of remifentanil & propofol administration

Time frame: Intraoperatively

Compare total doses of remifentanil and propofol administered intraoperatively between 2 groups.

Sponsors and collaborators

Lead sponsor

Seoul National University Hospital

Other

Registry information

Official study title

A Single Preoperative Injection of Dexmedetomidine Attenuates Haemodynamic Responses to Hydrodissection in Patients Undergoing Robotic Thyroidectomy: a Prospective Randomised Double-blinded Study

Acronym: DXM_Hydro

Important dates

Study start: 2012
Primary completion: 2012
Study completion: 2012
First posted: Apr 2, 2014
Registry last updated: Apr 2, 2014

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.