The Effect of Deliberate Hypotension on QTc, Tp-e Intervals and Heart Rate Variability

Deliberate hypotension is defined as lowering the systolic blood pressure to 80-90mmHg, or the mean blood pressure to 50-65mmHg. This technique is usually employed for operations that have a high risk of intraoperative hemorrhage, such as orthognathic surgery. Several different regimens are used to lower the patient's blood pressure, such as vasodilators, autonomic nervous system inhibitors, opioids and inhalation anesthetics. However, the effects that these agents have on the QTc and Tp-e intervals during deliberate hypotension is not known. Virtually every kind of anesthetic is reported to have some effect on the QTc and Tp-e intervals. Because orthognathic surgery usually takes 3-4 hours to complete, the amount of anesthetics and drugs used to maintain low blood pressure is not small. Therefore, the effect that these agents may have on the QTc and Tp-e intervals may not be negligible. The investigators of the present study found that the high dose of commonly used hypotensive agents tend to prolong these variabilities to some extent. This study will be able to provide insight as to which hypotensive anesthesia regimen has the least effect on the QTc and Tp-e intervals, and therefore will be helpful in minimizing cardiovascular risks of deliberate hypotensive anesthesia.

Study Overview

• Status: Completed
• Conditions: Mandibular Retrognathism; Mandibular Prognathism
• Intervention / Treatment: Drug: Group R; Drug: Group N; Drug: Group D

• Study Type: Interventional
• Enrollment (Actual): 66
• Phase: Phase 4

Contacts and Locations

Study Locations

• Korea, Republic of
  • Seoul, Korea, Republic of, 120-752
    • Young Jun Oh

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. ASA class 1
2. Adults over the age of 20
3. Patients requiring deliberate hypotensive anesthesia for orthognathic surgery

Exclusion Criteria:

1. Patient refusal
2. Patients with arrhythmia
3. Patients with cardiac anomalies or past history of cardiac surgery
4. Patients with abnormal electrolyte levels
5. Patients taking medications that are known to prolong QT intervals
6. Patients with QTc intervals greater than 440ms
7. Illiterate patients

Study Plan

How is the study designed?

Design Details

• Primary Purpose: PREVENTION
• Allocation: RANDOMIZED
• Interventional Model: PARALLEL
• Masking: QUADRUPLE

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: sevoflurane-remifentanil (group R); Continuous infusion of remifentanil at 0.05 ~ 2 mcg/kg/min with sevoflurane concentration of 1 MAC	Drug: Group R; Other Names: Continuous infusion of remifentanil at 0.05 ~ 2 mcg/kg/min with sevoflurane concentration of 1 MAC
ACTIVE_COMPARATOR: sevoflurane-nicardipine (group N); Continuous infusion of nicardipine at 1 ~ 7 mcg/kg/min with sevoflurane concentration of 1 MAC	Drug: Group N; Other Names: Continuous infusion of nicardipine at 1 ~ 7 mcg/kg/min with sevoflurane concentration of 1 MAC
ACTIVE_COMPARATOR: sevoflurane-dexmedetomidine (group D); Continuous infusion of dexmedetomidine at 0.2 ~ 1.0 mcg/kg/hr with sevoflurane concentration of 1 MAC	Drug: Group D; Other Names: Continuous infustion of dexmedetomidine at 0.2 ~ 1.0 mcg/kg/hr with sevoflurane concentration of 1 MAC

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Changes in QTc, Tp-e interval during deliberate hypotension	Before induction of anesthesia (T1), 10 minutes after induction of anesthesia (T2), 30 minutes after target blood pressure is reached (T3), every 60 minutes after from the end of surgery

Secondary Outcome Measures

Outcome Measure	Time Frame
Changes in Tp-e interval during deliberate hypotension	Before induction of anesthesia (T1), 10 minutes after induction of anesthesia (T2), 30 minutes after target blood pressure is reached (T3), every 60 minutes after from the end of surgery

Collaborators and Investigators

• Sponsor: Yonsei University

Study record dates

Study Major Dates

• Study Start: June 1, 2012
• Primary Completion (ACTUAL): February 1, 2013
• Study Completion (ACTUAL): February 1, 2013

Study Registration Dates

• First Submitted: June 25, 2012
• First Submitted That Met QC Criteria: July 5, 2012
• First Posted (ESTIMATE): July 6, 2012

Study Record Updates

• Last Update Posted (ACTUAL): March 19, 2019
• Last Update Submitted That Met QC Criteria: March 15, 2019
• Last Verified: March 1, 2019

More Information

Terms related to this study

• Keywords: Deliberate hypotension, QTc, Tp-e, heart rate variability
• Additional Relevant MeSH Terms: Congenital Abnormalities; Musculoskeletal Diseases; Stomatognathic Diseases; Tooth Diseases; Stomatognathic System Abnormalities; Jaw Abnormalities; Jaw Diseases; Maxillofacial Abnormalities; Craniofacial Abnormalities; Musculoskeletal Abnormalities; Mandibular Diseases; Malocclusion; Retrognathia; Prognathism; Malocclusion, Angle Class III; Physiological Effects of Drugs; Adrenergic Agents; Neurotransmitter Agents; Molecular Mechanisms of Pharmacological Action; Antihypertensive Agents; Vasodilator Agents; Central Nervous System Depressants; Peripheral Nervous System Agents; Analgesics; Sensory System Agents; Anesthetics, General; Anesthetics; Analgesics, Non-Narcotic; Platelet Aggregation Inhibitors; Adrenergic alpha-2 Receptor Agonists; Adrenergic alpha-Agonists; Adrenergic Agonists; Analgesics, Opioid; Narcotics; Membrane Transport Modulators; Hypnotics and Sedatives; Calcium-Regulating Hormones and Agents; Calcium Channel Blockers; Anesthetics, Inhalation; Remifentanil; Dexmedetomidine; Sevoflurane; Nicardipine
• Other Study ID Numbers: 4-2012-0242