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

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

Study Overview

• Status: Completed
• Conditions: Pain, Postoperative; Hypertensive Disease
• Intervention / Treatment: Other: SBP 20-30% over baseline; Other: SBP 20-30% under baseline

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.

• Study Type: Interventional
• Enrollment (Actual): 50
• Phase: Phase 4

Contacts and Locations

Study Locations

• Chile
  • Region Metropolitana
    • Santiago, Region Metropolitana, Chile, 8330024
      • Hospital Clinico Pontificia Universidad Catolica

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 20 years to 60 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

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

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: 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.	Other: 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.
Other: 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.	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

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Morphine requirement post laparoscopic cholecystectomy	Measure of morphine consumption during the first 24 postoperative hours in patients undergoing laparoscopic cholecystectomy.	First 24 hours postoperative

Secondary Outcome Measures

Outcome Measure	Time Frame
Effects of acute hypertension in pain scores	First 24 hours postoperative

Collaborators and Investigators

• Sponsor: Pontificia Universidad Catolica de Chile
• Investigators: Principal Investigator: Alejandro E Delfino, MD, Departamento de Anestesiología, Hospital Clínico Pontificia Universidad Católica de Chile

Study record dates

Study Major Dates

• Study Start: January 1, 2010
• Primary Completion (Actual): January 1, 2012
• Study Completion (Actual): January 1, 2012

Study Registration Dates

• First Submitted: January 19, 2013
• First Submitted That Met QC Criteria: July 8, 2013
• First Posted (Estimate): July 11, 2013

Study Record Updates

• Last Update Posted (Estimate): July 11, 2013
• Last Update Submitted That Met QC Criteria: July 8, 2013
• Last Verified: June 1, 2013

More Information

Terms related to this study

• Keywords: analgesia, postoperative;; analgesics opioid;; hyperalgesia;; remifentanil;; hypertension.
• Additional Relevant MeSH Terms: Pathologic Processes; Cardiovascular Diseases; Vascular Diseases; Postoperative Complications; Pain; Neurologic Manifestations; Hypertension; Pain, Postoperative
• Other Study ID Numbers: RIH_AP-UC-2012