Effect of Deep Versus Moderate Neuromuscular Block During Sevoflurane Anesthesia on Intraoperative Surgical Conditions.

Study Overview
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Brief Summary
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A deep neuromuscular block (NMB) is often associated with improved surgical conditions especially in laparoscopic surgery. We previously showed that deep NMB is superior to a moderate NMB under propofol anesthesia. However, this may not apply to sevoflurane anesthesia and sevoflurane by itself produces some degree of muscle relaxation. We therefore plan to investigate the effect of deep NMB on surgical conditions under sevoflurane anesthesia maintenance.

Detailed Description
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Neuromuscular blocking agents (NMBAs) are routinely administered during general anaesthesia to facilitate endotracheal intubation and to optimize surgical conditions. Increasing data suggest superiority of a deep neuromuscular block (defined by a post-tetanic count of 1-2 twitches) in creating optimal working conditions for the surgical team. However, it is unknown whether other aspects of the anaesthetic technique, most notably the choice of anaesthetic (for example, total intravenous versus inhalational anaesthesia), influence the relationship between the depth of the neuromuscular block and surgical conditions, particularly in laparoscopic surgery. Volatile anaesthetics are known for their ability to potentiate neuromuscular blocking agents an effect that is less existent with propofol. We previously showed that surgical working conditions in laparoscopic surgery during propofol anaesthesia are highly reliant on the depth of the neuromuscular block. Whether such a relationship also exists for inhalational anaesthetics, is unknown. To investigate this, we conducted a prospective, randomized, double blind study in which patients scheduled for laparoscopic renal surgery were randomized to receive either a moderate or a deep neuromuscular block during sevoflurane anaesthesia. The primary outcome was the intraoperative surgical condition assessed by a surgeon using the validated Leiden-Surgical Rating Scale. We hypothesized that the use of an inhalational anaesthetic would obviate the need for a deep NMB due to its intrinsic muscle relaxant potentiating properties to produce optimal working conditions.

Official Title
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Effect of Deep Versus Moderate Neuromuscular Block During Sevoflurane Anesthesia on Intraoperative Surgical Conditions in Patients Undergoing Laparoscopic Renal Surgery

Conditions
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Surgical Conditions

Intervention / Treatment
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* Drug: Deep neuromuscular block


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients diagnosed with renal or prostatic disease who are will undergo an elective laparoscopic renal surgical procedure or laparoscopic prostatectomy; American Society of Anesthesiologists (ASA) class I-III > 18 years of age; Ability to give oral and written informed consent. Exclusion Criteria: Known or suspected neuromuscular disorders impairing neuromuscular function; Allergies to muscle relaxants, anesthetics or narcotics; A (family) history of malignant hyperthermia; Women who are or may be pregnant or are currently breast feeding; Renal insufficiency, as defined by glomerular filtration rate < 30 ml/h creatinine. Previous retroperitoneal surgery at the site of the current surgery. Body mass index > 35 kg/m2

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Moderate neuromuscular block<br>Subjects will receive moderate neuromuscular block, aimed at 1-2 twitches train of four | |
| Experimental: Deep neuromuscular block<br>Subjects will receive deep neuromuscular block, aimed at 1-2 twitches post tetanic count | Drug: Deep neuromuscular block<br>* Deep neuromuscular block will be achieved with high dose rocuronium to achieve a depth of 1-2 twitches post tetanic count<br>* Other names: high dose rocuronium;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Leiden Surgical Rating Scale | During the on average 3 hour procedure, the surgical condition will be scored by the surgeon using a 5-point surgical rating scale at 15 minute intervals(1: poor ; 5: optimal) Mean and standard deviation of the average of all leiden surgical rating scale will be reported. | during surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative Measurements and Outcomes; Pain Scores | Postoperative measurements and outcomes of during PACU stay, all scores are reported as means and standard deviation of the average over the follow up period -mean pain scores (numeric rating scale; 0 no pain - 10 worst pain imaginable) | During post-anesthetic care unit stay (average stay 2 hours) at 15 minute intervals | 
| Intraoperative Hemodynamic Conditions | Perioperative average blood pressure will be reported, mean blood pressure ranging from 65 tot 110 millimeters mercury is considered normal | Perioperative measurements at 15 minute interval (on average during 3 hours) | 
| Postoperative Measurements and Outcomes; Sedation Levels | Postoperative measurements and outcomes of during PACU stay, all scores are reported as means and standard deviation of the average over the follow up period -ramsay sedation levels (0 = normal alertness, eyes open, responds normal to command 1 = drowsy with open eyes, closed and opened on command 2 = drowsy with closed eyes, opened in response to light auditory stimulus 3 = eyes closed, opened in response to rubbing the shoulder or a loud auditory stimulus 4 = eyes closed and opened only briefly in response to touching the subject 5 = eyes closed, unarousable by touch, aroused by painful 6 = unarousable by pain) | During post-anesthetic care unit stay (average stay 2 hours) at 15 minute intervals | 
| Postoperative Measurements and Outcomes; Saturation | Postoperative measurements and outcomes of during PACU stay, all scores are reported as means and standard deviation of the average over the follow up period -blood oxygen saturation in percent levels between 95-100 are considered normal | During post-anesthetic care unit stay (average stay 2 hours) at 15 minute intervals | 
| Intraoperative Nociception Level | The median and full range of the average nociception level index will be reported. The nociception level index consist of Ta multiparameter nonlinear combination of heart rate, heart rate variability, amplitude of the finger photoplethysmogram, skin conductance level, fluctuations in skin conductance, and their time derivatives, derived from random forest regression. Random forest is an algorithmic modeling approach that enables combining multiple parameters of different origin and discovering their complex nonlinear interactions. Normal range is between 10-20; 0 indicates no nociceptive events (in example, pain stimuli), 100 indicates severe painful stimuli. | Perioperative measurements at 15 minute interval (on average during 3 hours) |