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

This study has been completed.
Sponsor:
Information provided by (Responsible Party):
Yonsei University
ClinicalTrials.gov Identifier:
NCT01634594
First received: June 25, 2012
Last updated: February 13, 2013
Last verified: February 2013
  Purpose

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.


Condition Intervention Phase
Mandibular Prognathism,
Mandibular Retrognathism
Drug: Group R
Drug: Group N
Drug: Group D
Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Safety Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary Purpose: Prevention

Resource links provided by NLM:


Further study details as provided by Yonsei University:

Primary Outcome Measures:
  • Changes in QTc, Tp-e interval during deliberate hypotension [ Time Frame: 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 ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Changes in Tp-e interval during deliberate hypotension [ Time Frame: 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 ] [ Designated as safety issue: No ]

Enrollment: 66
Study Start Date: June 2012
Study Completion Date: February 2013
Primary Completion Date: February 2013 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
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 Name: 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 Name: 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 Name: Continuous infustion of dexmedetomidine at 0.2 ~ 1.0 mcg/kg/hr with sevoflurane concentration of 1 MAC

  Eligibility

Ages Eligible for Study:   20 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

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
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01634594

Locations
Korea, Republic of
Young Jun Oh
Seoul, Korea, Republic of, 120-752
Sponsors and Collaborators
Yonsei University
  More Information

No publications provided

Responsible Party: Yonsei University
ClinicalTrials.gov Identifier: NCT01634594     History of Changes
Other Study ID Numbers: 4-2012-0242
Study First Received: June 25, 2012
Last Updated: February 13, 2013
Health Authority: Korea: Food and Drug Administration

Keywords provided by Yonsei University:
Deliberate hypotension, QTc, Tp-e, heart rate variability

Additional relevant MeSH terms:
Malocclusion, Angle Class III
Prognathism
Retrognathia
Congenital Abnormalities
Craniofacial Abnormalities
Jaw Abnormalities
Jaw Diseases
Malocclusion
Mandibular Diseases
Maxillofacial Abnormalities
Musculoskeletal Abnormalities
Musculoskeletal Diseases
Stomatognathic Diseases
Stomatognathic System Abnormalities
Tooth Diseases
Dexmedetomidine
Nicardipine
Remifentanil
Sevoflurane
Adrenergic Agents
Adrenergic Agonists
Adrenergic alpha-2 Receptor Agonists
Adrenergic alpha-Agonists
Analgesics
Analgesics, Non-Narcotic
Analgesics, Opioid
Anesthetics
Anesthetics, General
Anesthetics, Inhalation
Anesthetics, Intravenous

ClinicalTrials.gov processed this record on October 21, 2014