Effect of Dexmedetomidine on Plasmatic Cortisol Response in Transsphenoidal Surgery

Phase 4

• Conditions: Pituitary Neoplasms
• Interventions: Drug: Sodium Chloride 0.9%; Drug: Dexmedetomidine

• Registration Number: NCT02549768
• Lead Sponsor: Pontificia Universidad Catolica de Chile

Brief Summary

Use of dexmedetomidine in pituitary tumor resection surgery as adjuvant drug and its relation to cortisol levels during postoperative period.

Detailed Description

Transsphenoidal resection of pituitary tumors is the neurosurgical procedure of choice to remove most of the tumors of the sellar region. Sometimes the intervention produces dysfunction of the hypothalamic-pituitary axis, and although most are transient, the risk associated with post-operative hypocortisolism determines its evaluation early in the postoperative period and the possibility of steroidal supplementation posteriorly. It is described that dexmedetomidine can be used as an adjuvant drug in this type of surgery being useful in reduction of total consumption of opioids and anesthetic gases, maintain hemodynamic stability and less time to recovery from anesthesia. Due to its sympatholytic effect, dexmedetomidine has been found to alter the intraoperative common neuroendocrine response generating lower levels of cortisol in the postoperative period than patients in which is not used.

The main objective of this study is to evaluate corticosteroid axis response (cortisol and adrenocorticotropic hormone) in patients undergoing transsphenoidal surgery under anesthesia with dexmedetomidine. A single-center randomized double-blind clinical trial will be conducted that will compare two groups of patients, one of which will be given dexmedetomidine (Dex group) and another group who will receive a placebo (control group). In addition the incidence of perioperative complications (nausea, vomiting, diabetes insipidus), intraoperative hemodynamics and patient comfort. The investigators expect that the normal stress response to surgery measured by cortisol and adrenocorticotropic hormone in the postoperative period will be reduced in the dexmedetomidine arm. This effect should be transient and attributed to use of dexmedetomidine and not to surgery.

Study Timeline

• Study Start: 2015-09
• Study First Submitted: 2015-09-06
• Study First Submitted QC: 2015-09-11
• Study First Posted: 2015-09-15
• Status Verified: 2016-10
• Last Update Submitted: 2016-10-10
• Last Update Posted: 2016-10-12
• Primary Completion: 2017-07
• Study Completion: 2017-08

Recruitment & Eligibility

• Status: UNKNOWN
• Sex: All
• Target Recruitment: 40

Inclusion Criteria

• American Society of Anesthesiologists physical status I or II.
• Pituitary tumour: non-functional macroadenoma, Rathke's cleft cyst, acromegaly.
• Normal hypothalamic-pituitary-adrenal axis by hormone levels measurement previous to surgery.

Exclusion Criteria

• Cushing disease.
• Pituitary apoplexy.
• Craniopharyngioma.
• Chronic corticosteroid use.
• Hemodynamic instability.
• Altered consciousness (Glasgow Coma Scale score less than 15).
• Atrioventricular block in any degree.
• Preoperative bradycardia.
• Alpha 2 agonist use (clonidine, alpha-methyldopa)
• Pregnancy or breast feeding.
• Known allergy to any of the study drugs.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Placebo	Sodium Chloride 0.9%	Use of crystalloid solution (sodium chloride 0.9%), injection pump programmed with drug "Dexmedetomidine" with 1 mcg/kg in 10 minutes, infusion 0.7 mcg/kg/h.
Dexmedetomidine	Dexmedetomidine	Use of dexmedetomidine during surgery (1 mcg/kg in 10 minutes, then infusion at 0.7 mcg/kg/h)

Primary Outcome Measures

Name	Time	Method
Cortisol plasmatic levels	24 hours after surgery	Venous blood sample

Secondary Outcome Measures

Name	Time	Method
Nausea and vomiting	24 hours after surgery	Semiquantitative measure
Pain	24 hours after surgery	By visual analogue scale
Patient comfort	24 hours after discharge from hospital	Scale ranging from 1 (very unsatisfied) to 5 (very satisfied)
Diabetes insipidus incidence	24 hours after surgery and 3 months after surgery	Clinical diagnosis by urine output (polyuria over 3 liters or urine per day) and/or hypernatremia (plasmatic sodium over 145 meq/L)
Adrenocorticotropin hormone	One hour after surgery, 24 hours after surgery, 48 hours after surgery	Venous blood sample
Hemodynamics	From start of anesthesia to end of anesthesia	Heart rate and arterial pressure
Cerebrospinal fluid fistula	3 months after surgery	Clinical diagnosis made by neurosurgeon
Cortisol plasmatic levels	1 hour after surgery, 48 hours after surgery, 3 months after surgery	Venous blood sample

Trial Locations

Locations (1)

Division de Anestesia - Pontificia Universidad Catolica de Chile; 🇨🇱 Santiago, Region Metropolitana, Chile