Effects of Nitroglycerin Versus Labetalol on Tissue Perfusion During Deliberate Hypotension

Cairo University (CU)

Status and phase: Completed; Phase 4

Conditions: Deliberate Hypotension; Sinus Endoscopic Surgery; Tissue Perfusion

Treatments: Drug: Nitroglycerin; Drug: Labetalol

Study type: Interventional

Funder types: Other

Identifiers

NCT03809065

N53-2016

Details and patient eligibility

About

Deliberate hypotension is used to provide bloodless field during endoscopic sinus surgery; however, hypotension might impair perfusion of vital organs. The aim of this work is to compare the impact of nitroglycerin and labetalol on peripheral perfusion when used for induction of deliberate hypotension

Full description

Hypotensive anesthesia is associated with the risk of reduced tissue perfusion. The usual target mean arterial pressure during deliberate hypotension is 50- 65 mmHg; however, the status of peripheral perfusion under this target is not well investigated. Nitroglycerin and Labetalol are commonly used drugs to achieve deliberate hypotension. Nitroglycerin is a direct vasodilator and its main action is through venodilation, while labetalol combines a selective α1 and non selective beta-adrenergic blocking activity. Both drugs were previously compared during deliberate hypotension with regard to surgical field quality and blood loss. No study to date compared the effects of both drugs on peripheral perfusion when used for induction of deliberate hypotension. The Peripheral Perfusion Index (PPI) is the ratio between pulsatile and non-pulsatile components of peripheral circulation. Measurement of PPI is based on analysis of the pulse oximetry signal. PPI showed increasing popularity as a non invasive monitor of peripheral perfusion. Serum lactate is another frequently used marker of global tissue perfusion.The aim of this study is to compare the influence of nitroglycerin and labetalol on tissue perfusion when used for induction of deliberate hypotension during FESS operations. Tissue perfusion will be evaluated using PPI and serum lactate as markers of peripheral and global tissue perfusion respectively.

Enrollment: 40 patients

Sex: All

Ages: 18 to 45 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Adult male or female patients
• 18-45 years
• ASA physical status I-II
• scheduled for FESS operations

Exclusion criteria

• uncontrolled hypertension
• cerebrovascular disorders
• coagulation disorders
• cardiovascular diseases
• renal impairment
• liver impairment
• history of allergic reaction to any of the study medications

Trial design

Primary purpose: Supportive Care

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Triple Blind

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40 participants in 2 patient groups

group N

Experimental group

Description:

Patients in this group will receive Nitroglycerin infusion for deliberate hypotension at a rate of 0.5-2 μg /kg/min .

Treatment:

Drug: Nitroglycerin

group L

Active Comparator group

Description:

Patients in this group will receive Labetalol infusion for deliberate hypotension at a rate of be 0.5-2 mg/kg/h .

Treatment:

Drug: Labetalol