Effects of Neuromuscular Blockade Level and Intra-abdominal Pressure on Surgical Conditions and Cardiopulmonary Responses During Laparoscopic Colon Surgery With the Trendelenburg Position

Study Overview
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Brief Summary
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The purpose of this study is to find out the effect of low abdominal pressure vs. standard abdominal pressure on the cardiac and respiratory function of the patients undergoing laparoscopic colon surgery in Trendelenberg position. It was also designed to evaluate the effect of the degree of neuromuscular blockade on the surgical condition of the patients undergoing laparoscopic colon surgery in Trendelenberg position.

Conditions
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Cardiac Index

Intervention / Treatment
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* Device: Standard abdominal pressure
* Device: Low abdominal pressure
* Drug: Conventional neuromuscular blockade
* Drug: Deep neuromuscular blockade


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients scheduled for laparoscopic colon surgery under Trendelenberg position Exclusion Criteria: ASA classification IV Unable to make a written, informed consent Allergic to neuromuscular blocking agents, anesthetics, opioids Patients with neuromuscular disease Hepatic failure Renal failure History of malignant hyperthermia Morbid obesity with BMI>35 kg/m2 Patients enrolled in another clinical trials

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 90 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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: CS<br>Patients who receive laparoscopic colon surgery under Trendelenberg position with conventional neuromuscular blockade and standard abdominal pressure. | Device: Standard abdominal pressure<br>* Abdominal pressure maintained 12mmHg throughout laparoscopic colon surgery<br>Drug: Conventional neuromuscular blockade<br>* Anesthesia induction with rocuronium 0.4mg/kg and maintenance with rocuronium 0.15mg/kg to maintain TOF 1-2 twitch<br>|
| Experimental: DS<br>Patients who receive laparoscopic colon surgery under Trendelenberg position with deep neuromuscular blockade and standard abdominal pressure. | Device: Standard abdominal pressure<br>* Abdominal pressure maintained 12mmHg throughout laparoscopic colon surgery<br>Drug: Deep neuromuscular blockade<br>* Anesthesia induction with rocuronium 0.8mg/kg → maintenance with rocuronium 0.3mg/kg to maintain PTC 1-2 twitch<br>|
| Experimental: DL<br>Patients who receive laparoscopic colon surgery under Trendelenberg position with deep neuromuscular blockade and low abdominal pressure. | Device: Low abdominal pressure<br>* Abdominal pressure maintained 8mmHg throughout laparoscopic colon surgery<br>* Other names: Abdominal pressure;Drug: Deep neuromuscular blockade<br>* Anesthesia induction with rocuronium 0.8mg/kg → maintenance with rocuronium 0.3mg/kg to maintain PTC 1-2 twitch<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cardiac Index | Cardiac index 30 min after onset of laparoscopy. The cardiac index was measured with an arterial waveform analysis system (FloTrac/EV1000, version 4.0; Edwards Life Sciences, Irvine, CA, USA) from the radial artery. | 30 min after onset of laparoscopy | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean Arterial Blood Pressure (MBP) | Mean arterial blood pressure measured during laparoscopic surgery. The mean arterial blood pressure was measured with an arterial waveform analysis system (FloTrac/EV1000, version 4.0; Edwards Life Sciences, Irvine, CA, USA) from the radial artery. | 1, 30, 60, 90, and 120 minutes after onset of laparoscopy | 
| Stroke Volume Index (SVI) | Stroke volume index during the surgery. The stroke volume index was measured with an arterial waveform analysis system (FloTrac/EV1000, version 4.0; Edwards Life Sciences, Irvine, CA, USA) from the radial artery. | 1, 30, 60, 90, 120 min after onset of laparoscopy | 
| PaO2 | PaO2 measured during laparoscopic surgery. The PaO2 (arterial partial pressure of oxygen) was measured with the blood gas analyzer (GEM Premier 3000, Model 5700; Instrumentation Laboratory, Lexington, MA, USA). | 1, 30, 60, 90, and 120 minutes after onset of laparoscopy | 
| Pulmonary Compliance | Pulmonary compliance during laparoscopic surgery. The pulmonary compliance was calculated from the plateau and peak inspiratory pressures, positive end-expiratory pressure, and tidal volume measured with an anesthetic machine (Primus; Dräger, Lübeck, Germany). | 1, 30, 60, 90, and 120 minutes after onset of laparoscopy | 
| Surgical Rating Scale | The surgical rating scale was assessed by the surgeon and graded as a five-point scale: optimal, good, acceptable, poor, and extremely poor conditions. | 1 min after laparoscopic procedure |