Effect of Acute Arterial Hypertension on Morphine's Requirements and Postsurgical Pain.

NCT ID: NCT01897155

Last Updated: 2013-07-11

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: PHASE4
• Total Enrollment: 50 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2010-01-31
• Study Completion Date: 2012-01-31

Brief Summary

The purpose of this randomized clinical trial is to evaluate the effect of acute arterial hypertension maintained during surgery on morphine's requirements in patients undergoing laparoscopic cholecystectomy

Detailed Description

The high arterial blood pressure has been correlated with an increase in pain threshold in animal and humans. One of the explanations to this phenomenon is a baroreceptor activity and vasopressin release at the level of spinal cord dorsal horn and hypothalamus.

As far as we know, there is only one study about the effect of chronic hypertension on postoperative pain and none with acute hypertension. We therefore decided to conduct a randomized controlled trial to evaluate the effect of acute hypertension on postoperative morphine's requirements.

Conditions

Hypertensive Disease; Pain, Postoperative

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: SUPPORTIVE_CARE
• Blinding Strategy: QUADRUPLE

Study Groups

SBP 20-30% under baseline

Induction of anesthesia was performed with remifentanil, pentothal 3 mg/kg and atracurium 0.5 mg/Kg. Anaesthesia was maintained with remifentanil (0.4 ug/Kg/min) and isoflurane adjusted to bispectral index (40-60). Patients received a phenylephrine infusion to maintain systolic blood pressure (SBP) 20% to 30% under baseline. The lower limit of SBP was 75 mmHg. In the recovery room, morphine was administered routinely at doses of 3 mg IV every 15 minutes until pain was less than 4 estimated by visual analog scale (VAS). VAS and pain threshold with von Frey filaments were assessed at 2, 6, 12 and 24 postoperative hours. All patients, received ketorolac 30 mg IV every 8 hours and intravenous morphine administered by patient controlled analgesia system (PCA) during the first 24 hours.

Group Type: OTHER

SBP 20-30% over baseline

Intervention Type: OTHER

Patients were assigned to receive a phenylephrine infusion in order to maintain systolic blood pressure (SBP) 20% to 30% over the baseline. The upper limit of systolic blood pressure is 165 mmHg.

SBP 20-30% over baseline

Induction of anesthesia was performed with remifentanil, pentothal 3 mg/kg and atracurium 0.5 mg/Kg. Anaesthesia was maintained with remifentanil (0.4 ug/Kg/min) and isoflurane adjusted to bispectral index(40-60). Patients received a phenylephrine infusion in order to maintain systolic blood pressure (SBP) 20% to 30% over baseline. The upper limit of SBP was 165 mmHg. In the recovery room, morphine was administered routinely at doses of 3 mg IV every 15 minutes until pain was less than 4 estimated by visual analog scale (VAS). VAS and pain threshold with von Frey filaments were assessed at 2, 6, 12 and 24 postoperative hours. All patients, received ketorolac 30 mg IV every 8 hours and intravenous morphine administered by patient controlled analgesia system (PCA) during the first 24 hours.

Group Type: OTHER

SBP 20-30% under baseline

Intervention Type: OTHER

Patients were assigned to receive a phenylephrine infusion in order to maintain systolic blood pressure (SBP) 20% to 30% below the baseline. The lower limit of systolic blood pressure is 75 mmHg

Interventions

SBP 20-30% over baseline

Patients were assigned to receive a phenylephrine infusion in order to maintain systolic blood pressure (SBP) 20% to 30% over the baseline. The upper limit of systolic blood pressure is 165 mmHg.

Intervention Type: OTHER

SBP 20-30% under baseline

Patients were assigned to receive a phenylephrine infusion in order to maintain systolic blood pressure (SBP) 20% to 30% below the baseline. The lower limit of systolic blood pressure is 75 mmHg

Intervention Type: OTHER

Eligibility Criteria

Inclusion Criteria

• American Society of Anesthesiology patient classification status(ASA) I-II
• Between 20 and 60 years of age
• Programed for elective laparoscopic cholecystectomy

Exclusion Criteria

• History of arterial hypertension
• Baseline blood pressure over 139/89
• Use of opioids and any analgesic drug during the last 24 hours before surgery
• Chronic use of nonsteroidal antiinflammatory
• BMI > 34.9
• History of drug or alcohol abuse
• Use of medications that interfere in the central nervous system
• Adverse reactions to the drugs used in the study
• Pregnancy

• Minimum Eligible Age: 20 Years
• Maximum Eligible Age: 60 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Pontificia Universidad Catolica de Chile

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Alejandro E Delfino, MD

Role: PRINCIPAL_INVESTIGATOR

Departamento de Anestesiología, Hospital Clínico Pontificia Universidad Católica de Chile

Locations

Hospital Clinico Pontificia Universidad Catolica

Santiago, Santiago Metropolitan, Chile

Countries

Chile

Other Identifiers

RIH_AP-UC-2012

Identifier Type: -

Identifier Source: org_study_id