<clinical_study>
  <!-- This xml conforms to an XML Schema at:
    https://clinicaltrials.gov/ct2/html/images/info/public.xsd -->
  <required_header>
    <download_date>ClinicalTrials.gov processed this data on September 20, 2023</download_date>
    <link_text>Link to the current ClinicalTrials.gov record.</link_text>
    <url>https://clinicaltrials.gov/ct2/show/NCT02264444</url>
  </required_header>
  <id_info>
    <org_study_id>461326</org_study_id>
    <nct_id>NCT02264444</nct_id>
  </id_info>
  <brief_title>Establishing Visualization Grading Scale on LESS Cholecystectomy</brief_title>
  <official_title>A Grading System for Laparoscopic Visualization and Predicting Factors That Affect Visualization Level During Laparoscopic Cholecystectomies: A Prospective, Single Group, Open Label Study</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>Florida Hospital Tampa Bay Division</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
    <collaborator>
      <agency>Merck Sharp &amp; Dohme LLC</agency>
      <agency_class>Industry</agency_class>
    </collaborator>
  </sponsors>
  <source>Florida Hospital Tampa Bay Division</source>
  <oversight_info>
    <has_dmc>No</has_dmc>
  </oversight_info>
  <brief_summary>
    <textblock>
      Essential to laparoscopic operations is adequate visualization. Unfortunately there is no&#xD;
      grading system to assess the degree or quality of visualization. The primary objective of the&#xD;
      project is to develop a laparoscopic visualization scoring system. We also intend to&#xD;
      investigate the effects of neuromuscular blockade agents on visualization.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      Essential to laparoscopic operations is adequate visualization. Unfortunately there is no&#xD;
      grading system to assess the degree or quality of visualization. There are many contributing&#xD;
      factors that either assist or hinder the quality. Compared to open surgical procedures,&#xD;
      laparoscopic surgical procedures (Laparo-endoscopic Single Site (LESS) and conventional&#xD;
      multiport) are associated with less postoperative pain, a lower wound infection rate, shorter&#xD;
      length of hospital stays and reduced incidence of late ventral hernia(1). Despite these well&#xD;
      documented benefits of laparoscopic procedures, laparoscopy in certain patient populations&#xD;
      can be challenging. Preoperative factors that contribute to technical difficulty in&#xD;
      performance of laparoscopic procedures include male gender, android body habitus, and body&#xD;
      mass index (BMI) greater than 30 kg/m2(2). Men often have an android body habitus, whereby&#xD;
      the excess body fat concentrates within the peritoneal cavity, increases intra-abdominal&#xD;
      pressure and thus reduces intraoperative laparoscopic visualization. Intra-abdominal pressure&#xD;
      measured in morbidly obese patients is 2-3 times higher than in non-obese patients. In&#xD;
      addition, android body habitus and high BMI are often associated with an enlarged left lobe&#xD;
      of the liver. These factors can contribute to the degree of intraoperative technical&#xD;
      difficulty and should be weighed in selection of appropriate patients to undergo laparoscopic&#xD;
      procedures.&#xD;
&#xD;
      Particularly in the early period of the surgeon's learning curve, we suggest that selection&#xD;
      criteria for laparoscopic procedures for the upper abdomen be limited to patients with a low&#xD;
      BMI and no previous upper abdominal surgery. Although low BMI is a relatively good predictor&#xD;
      of a less challenging laparoscopic procedure, a high BMI does not necessarily predict&#xD;
      intraoperative technical difficulty. We predict that the best method to determine the&#xD;
      technical difficulty of laparoscopic procedures is during intraoperative evaluation. For&#xD;
      example, the primary limiting factor in determining the technical difficulty of laparoscopic&#xD;
      Roux-en-Y gastric bypass (RYGBP) is the size and thickness of the left lobe of the liver. A&#xD;
      massively enlarged left lobe of the liver obscures the laparoscopic view of the&#xD;
      gastro-esophageal junction and angle of His, making the gastrojejunal anastomosis difficult&#xD;
      to construct. Schwartz et al. support this concept when they found that a large liver was the&#xD;
      primary reason for conversion from laparoscopic to open RYGBP in an analysis of 1,000&#xD;
      patients (2).&#xD;
&#xD;
      A laparoscopic operation consists of making small punctures into the peritoneum, through&#xD;
      which, a camera and surgical instruments are subsequently inserted. The laparoscopically&#xD;
      placed camera is the only view of the operative field. Since this point of view is constantly&#xD;
      changing to meet the surgeon's needs during the operation, and because it is very different&#xD;
      from the exoscopic view of the surgeon, the surgeon has to be very well trained to interpret&#xD;
      the images through the laparoscopic view. For LESS operations, a deflectable tip laparoscope&#xD;
      is utilized in aiding the surgeon for improved visibility and less clashing of instruments.&#xD;
&#xD;
      The laparoscopic view does not reveal, at one time, all the structures the surgeon needs to&#xD;
      see in order to complete the surgical procedure with success. These structures can, for&#xD;
      instance, be hidden behind the peritoneal wall (e.g., the ureter). This limitation cannot&#xD;
      only lead to a less efficient operation, but can also lead to complications. Often such&#xD;
      structures can be extracted from preoperative CT/MR images; however, the surgeon needs to&#xD;
      interpret and fuse these images with the laparoscopic view. To alleviate this problem, we&#xD;
      propose a laparoscopic visualization scoring system based on the intraoperative quality of&#xD;
      images (3).&#xD;
&#xD;
      The impact of muscle relaxants on the isolated abdominal wall or diaphragmatic behavior and&#xD;
      the absolute intra-abdominal volume are difficult to measure. Conversely, the inflated&#xD;
      volume-pressure relationship of the abdominal cavity is easier to measure. A description of&#xD;
      this volume-pressure relationship has not been identified in previous studies. Clinical data&#xD;
      supports a positive linear correlation between the depth of neuromuscular blockade and&#xD;
      abdominal wall and diaphragmatic relaxation and compliance (4). There is a very tangible and&#xD;
      real effect of the neuromuscular blockade; this ultimately has a direct impact on the quality&#xD;
      of visualization of the surgical field during a laparoscopic procedure (5). A constant&#xD;
      neuromuscular block leads to preferable working conditions for the surgeon. The evoked muscle&#xD;
      responses after neurostimulation can be registered by electromyography (EMG),&#xD;
      mechanomyography (MMG) and acceleromyography (AMG). In principle, different peripheral nerves&#xD;
      can be used for neurostimulation. The EMG records the electrical signal generated by the&#xD;
      muscular action potential under its surface electrodes. The force of the thumb after&#xD;
      stimulation can be registered by MMG. The AMG records the acceleration of the thumb after&#xD;
      neurostimulation. The EMG, MMG and AMG system allows for observation of the measured signals&#xD;
      quantity and quality (6).&#xD;
&#xD;
      We have identified other relevant factors that significantly affect the quality of&#xD;
      visualization during different laparoscopic procedures including:&#xD;
&#xD;
        1. Clarity, focus and brightness:&#xD;
&#xD;
           The laparoscope typically consists of an outer ring of optical fibers used to transmit&#xD;
           light into the body, and an inner core of rod lenses that illuminate visual scene. This&#xD;
           is then relayed back to the camera. Various different types of laparoscopes are&#xD;
           available; they are specified in terms of overall length, number of rods, diameter and&#xD;
           angle of view. Generally speaking, the wider the scope the brighter the resulting image.&#xD;
           Lenses are available in the range of 1.9mm to 12mm, but sizes of 5mm and 10mm are the&#xD;
           most common choices for pediatric and adult patients, respectively.&#xD;
&#xD;
        2. Breadth of intra-abdominal field and vertical space measured in centimeters:&#xD;
&#xD;
           Breadth of intra-abdominal field and vertical space are factors directly related to&#xD;
           pressure insufflation as well as the level of the neuromuscular blockade.&#xD;
&#xD;
        3. Distracting factors:&#xD;
&#xD;
           This specific category of distracting factors includes:&#xD;
&#xD;
             1. Blood: the presence, especially in large quantities, may prevent adequate&#xD;
                visualization.&#xD;
&#xD;
             2. Smoke: unipolar electrocautery and/or the bipolar Maryland forceps produce smoke&#xD;
                when used. The rate of aspiration and evacuation also affect visualization.&#xD;
&#xD;
             3. Adhesions: the presence of intra-abdominal adhesions, which hinders and prohibits&#xD;
                proper identification of the anatomic structures.&#xD;
&#xD;
             4. Sterile iodine impregnated covering sheet: its application presumably has a&#xD;
                negative impact on abdominal wall and diaphragmatic compliance, and therefore, may&#xD;
                obscure visualization.&#xD;
&#xD;
             5. Intra-intestinal air: the presence of air inside the stomach, and small and large&#xD;
                intestines adversely affects the size of the visual field. This can be prevented by&#xD;
                an adequate preoperative bowel preparation and placement of an aspiration NG tube&#xD;
                during anesthesia induction.&#xD;
&#xD;
        4. Patient's specific factors such as BMI value and body habitus:&#xD;
&#xD;
           From our experience, a BMI under 26 allows for optimal field visualization. Conversely,&#xD;
           a BMI greater than 26 negatively impacts the visual field. However, a recent study&#xD;
           conducted by Camani et al. in 2010 showed that the laparoscopic approach in the various&#xD;
           applications of gynecologic surgery is not significantly influenced by BMI in terms of&#xD;
           surgical outcomes, laparotomy conversion rate, intraoperative and postoperative&#xD;
           complication rate, and duration of hospital stay (4). We feel that visualization during&#xD;
           operations involving the abdominal cavity are adversely affected by high amounts of&#xD;
           adipose tissue, and therefore, a visualization scoring system will help support this&#xD;
           theory.&#xD;
&#xD;
        5. Type of disorder (malignant vs. benign) that the laparoscopic procedure is undertaken&#xD;
           for:&#xD;
&#xD;
           Due to many pathologic factors such as the need for R0 resections, the discovery of more&#xD;
           advanced disease than anticipated, the presence of adhesions or scar tissue from&#xD;
           previous operations, laparoscopic procedures for malignant disorders may require a&#xD;
           better visualization field than laparoscopic procedures undertaken for benign disorders.&#xD;
&#xD;
        6. Inadequate and/or poorly designed instruments:&#xD;
&#xD;
           Most laparoscopic instrument development is technology-driven. This approach to&#xD;
           instrument design does not always consider the ergonomics of the users, therefore&#xD;
           leading to a user-unfriendly product (4, 5).&#xD;
&#xD;
        7. Technical difficulties:&#xD;
&#xD;
           An intraoperative technical difficulty is defined as a significant deviation from the&#xD;
           ordinary surgical procedure. All conversions to an open operation and iatrogenic bowel&#xD;
           perforation during laparoscopic surgery are examples of technical difficulties. Many&#xD;
           studies demonstrate that a technical difficulty during laparoscopic-assisted surgery&#xD;
           jeopardizes both the intra-operative and postoperative patient safety.&#xD;
&#xD;
        8. Patient's body position during laparoscopic procedure:&#xD;
&#xD;
      A study led by Mulier, J et al. in 2010 demonstrated that the Trendelenburg position for&#xD;
      lower abdominal surgery and reverse Trendelenburg with flexing of the legs at the hips for&#xD;
      upper abdominal surgery effectively improved the workspace in obese patients, even with full&#xD;
      muscle relaxation (6).&#xD;
&#xD;
      II. Objectives A.Primary Objective The primary objective is to develop a laparoscopic&#xD;
      visualization scoring system.&#xD;
&#xD;
      B. Secondary Objectives&#xD;
&#xD;
      The secondary objectives are:&#xD;
&#xD;
        1. To determine how visualization is affected by various levels of pneumoperitoneum&#xD;
           correlated with neuromuscular blockade.&#xD;
&#xD;
        2. Identify the factors that influence visualization, and determine how to manage these&#xD;
           factors to optimize visualization.&#xD;
&#xD;
        3. Determine if there is a statistically significant correlation between different degrees&#xD;
           of visualization and the following intraoperative time intervals:&#xD;
&#xD;
             1. surgical incision to sterile wound dressing&#xD;
&#xD;
             2. sterile wound dressing to extubation&#xD;
&#xD;
             3. sterile wound dressing to patient exiting operating room&#xD;
&#xD;
        4. Determine if there is a statistically significant correlation between different degrees&#xD;
           of visualization and postoperative pain.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Completed</overall_status>
  <start_date>September 2013</start_date>
  <completion_date type="Actual">August 2016</completion_date>
  <primary_completion_date type="Actual">June 2016</primary_completion_date>
  <phase>N/A</phase>
  <study_type>Interventional</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <allocation>N/A</allocation>
    <intervention_model>Single Group Assignment</intervention_model>
    <primary_purpose>Treatment</primary_purpose>
    <masking>None (Open Label)</masking>
  </study_design_info>
  <primary_outcome>
    <measure>Laparoscopic Visualization Score assessment</measure>
    <time_frame>Start to end of LESS Cholecystectomy</time_frame>
  </primary_outcome>
  <secondary_outcome>
    <measure>pneumoperitoneum volume</measure>
    <time_frame>start to end of LESS cholecystectomy</time_frame>
  </secondary_outcome>
  <secondary_outcome>
    <measure>factors influencing visualization</measure>
    <time_frame>start to end of LESS cholecystectomy</time_frame>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Degrees of visualization</measure>
    <time_frame>start to end of LESS cholecystectomy</time_frame>
    <description>surgical incision to sterile wound dressing&#xD;
sterile wound dressing to extubation&#xD;
sterile wound dressing to patient exiting operating room</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>postoperative pain</measure>
    <time_frame>every day until 7 days after LESS cholecystectomy</time_frame>
  </secondary_outcome>
  <number_of_arms>1</number_of_arms>
  <enrollment type="Actual">30</enrollment>
  <condition>Cholecystitis</condition>
  <arm_group>
    <arm_group_label>Cholecystectomy visualization</arm_group_label>
    <arm_group_type>Experimental</arm_group_type>
    <description>All patients will undergo a standard single site cholecystectomy and will have their operation recorded and scored for visualization.</description>
  </arm_group>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Cholecystectomy visualization</intervention_name>
    <description>Patients undergo a standard removal of the gallbladder through a single incision at the umbilicus will have their operation recorded and graded according to a scale that is established for this study.</description>
    <arm_group_label>Cholecystectomy visualization</arm_group_label>
  </intervention>
  <eligibility>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  Signed informed consent&#xD;
&#xD;
          -  18 years of age and older&#xD;
&#xD;
          -  All patients deemed to have a clinical and surgical indication to undergo a LESS&#xD;
             cholecystectomy&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          1. Pregnancy&#xD;
&#xD;
          2. Breastfeeding&#xD;
&#xD;
          3. BMI&gt;35&#xD;
&#xD;
          4. Serious comorbidities precluding a LESS cholecystectomy&#xD;
&#xD;
          5. Known or suspected neuromuscular disorders impairing neuromuscular function&#xD;
&#xD;
          6. Allergies to muscle relaxants, anesthetics or narcotics utilized for this study&#xD;
&#xD;
          7. A (family) history of malignant hyperthermia&#xD;
&#xD;
          8. A contraindication for neostigmine administration&#xD;
&#xD;
          9. Chronic opioid use&#xD;
&#xD;
         10. Prolonged QT syndrome&#xD;
&#xD;
         11. Creatinine &gt;2.0&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>18 Years</minimum_age>
    <maximum_age>N/A</maximum_age>
    <healthy_volunteers>Accepts Healthy Volunteers</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>Alexander S. Rosemurgy, MD</last_name>
    <role>Principal Investigator</role>
    <affiliation>Florida Hospital Tampa Bay Division</affiliation>
  </overall_official>
  <location>
    <facility>
      <name>FloridaHTBD</name>
      <address>
        <city>Tampa</city>
        <state>Florida</state>
        <zip>33613</zip>
        <country>United States</country>
      </address>
    </facility>
  </location>
  <location_countries>
    <country>United States</country>
  </location_countries>
  <reference>
    <citation>Schrenk P, Woisetschlager R, Rieger R, Wayand WU. A diagnostic score to predict the difficulty of a laparoscopic cholecystectomy from preoperative variables. Surg Endosc. 1998 Feb;12(2):148-50. doi: 10.1007/s004649900616.</citation>
    <PMID>9479730</PMID>
  </reference>
  <reference>
    <citation>Nguyen NT, Longoria M, Gelfand DV, Sabio A, Wilson SE. Staged laparoscopic Roux-en-Y: a novel two-stage bariatric operation as an alternative in the super-obese with massively enlarged liver. Obes Surg. 2005 Aug;15(7):1077-81. doi: 10.1381/0960892054621062.</citation>
    <PMID>16105411</PMID>
  </reference>
  <reference>
    <citation>Stijn de Buck, Johan van Cleynenbreugel, Indra Geys, Thomas Koninckx, Philippe R Koninck, Paul Suetens. A System to Support Laparoscopic Surgery by Augmented Reality Visualization. Medical Image Computing and Computer-Assisted Intervention; 691-8, 2001.</citation>
  </reference>
  <reference>
    <citation>Camanni M, Bonino L, Delpiano EM, Migliaretti G, Berchialla P, Deltetto F. Laparoscopy and body mass index: feasibility and outcome in obese patients treated for gynecologic diseases. J Minim Invasive Gynecol. 2010 Sep-Oct;17(5):576-82. doi: 10.1016/j.jmig.2010.04.002. Epub 2010 Jul 8.</citation>
    <PMID>20619751</PMID>
  </reference>
  <reference>
    <citation>McDougall EM, Figenshau RS, Clayman RV, Monk TG, Smith DS. Laparoscopic pneumoperitoneum: impact of body habitus. J Laparoendosc Surg. 1994 Dec;4(6):385-91. doi: 10.1089/lps.1994.4.385.</citation>
    <PMID>7881141</PMID>
  </reference>
  <reference>
    <citation>Mulier JP, Dillemans B, Van Cauwenberge S. Impact of the patient's body position on the intraabdominal workspace during laparoscopic surgery. Surg Endosc. 2010 Jun;24(6):1398-402. doi: 10.1007/s00464-009-0785-8. Epub 2010 Jan 7.</citation>
    <PMID>20054583</PMID>
  </reference>
  <reference>
    <citation>Simanski , R. Kahler, B. Pohl, R. Hofmockel, R. Friedrich, B. P. Lampe Measurement and control of neuromuscular blockade and depth of anaesthesia. Proceedings of the European Control Conference, Cambridge/UK. 2003.</citation>
  </reference>
  <verification_date>July 2017</verification_date>
  <study_first_submitted>October 1, 2014</study_first_submitted>
  <study_first_submitted_qc>October 9, 2014</study_first_submitted_qc>
  <study_first_posted type="Estimate">October 15, 2014</study_first_posted>
  <last_update_submitted>July 26, 2017</last_update_submitted>
  <last_update_submitted_qc>July 26, 2017</last_update_submitted_qc>
  <last_update_posted type="Actual">July 28, 2017</last_update_posted>
  <responsible_party>
    <responsible_party_type>Principal Investigator</responsible_party_type>
    <investigator_affiliation>Florida Hospital Tampa Bay Division</investigator_affiliation>
    <investigator_full_name>Alexander Rosemurgy</investigator_full_name>
    <investigator_title>Director HPB Surgery, GERD Center</investigator_title>
  </responsible_party>
  <keyword>Cholecystectomy, visualization, single incision</keyword>
  <condition_browse>
    <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
    <mesh_term>Cholecystitis</mesh_term>
  </condition_browse>
  <patient_data>
    <sharing_ipd>No</sharing_ipd>
  </patient_data>
  <!-- Results have not yet been posted for this study                                          -->
</clinical_study>


download date: ClinicalTrials.gov processed this data on September 20, 2023
link text: Link to the current ClinicalTrials.gov record.
url: https://clinicaltrials.gov/ct2/show/NCT02264444
org study id: 461326
nct id: NCT02264444
lead sponsor: 
collaborator: 
has dmc: No
Essential to laparoscopic operations is adequate visualization. Unfortunately there is no
      grading system to assess the degree or quality of visualization. The primary objective of the
      project is to develop a laparoscopic visualization scoring system. We also intend to
      investigate the effects of neuromuscular blockade agents on visualization.
Essential to laparoscopic operations is adequate visualization. Unfortunately there is no
      grading system to assess the degree or quality of visualization. There are many contributing
      factors that either assist or hinder the quality. Compared to open surgical procedures,
      laparoscopic surgical procedures (Laparo-endoscopic Single Site (LESS) and conventional
      multiport) are associated with less postoperative pain, a lower wound infection rate, shorter
      length of hospital stays and reduced incidence of late ventral hernia(1). Despite these well
      documented benefits of laparoscopic procedures, laparoscopy in certain patient populations
      can be challenging. Preoperative factors that contribute to technical difficulty in
      performance of laparoscopic procedures include male gender, android body habitus, and body
      mass index (BMI) greater than 30 kg/m2(2). Men often have an android body habitus, whereby
      the excess body fat concentrates within the peritoneal cavity, increases intra-abdominal
      pressure and thus reduces intraoperative laparoscopic visualization. Intra-abdominal pressure
      measured in morbidly obese patients is 2-3 times higher than in non-obese patients. In
      addition, android body habitus and high BMI are often associated with an enlarged left lobe
      of the liver. These factors can contribute to the degree of intraoperative technical
      difficulty and should be weighed in selection of appropriate patients to undergo laparoscopic
      procedures.

      Particularly in the early period of the surgeon's learning curve, we suggest that selection
      criteria for laparoscopic procedures for the upper abdomen be limited to patients with a low
      BMI and no previous upper abdominal surgery. Although low BMI is a relatively good predictor
      of a less challenging laparoscopic procedure, a high BMI does not necessarily predict
      intraoperative technical difficulty. We predict that the best method to determine the
      technical difficulty of laparoscopic procedures is during intraoperative evaluation. For
      example, the primary limiting factor in determining the technical difficulty of laparoscopic
      Roux-en-Y gastric bypass (RYGBP) is the size and thickness of the left lobe of the liver. A
      massively enlarged left lobe of the liver obscures the laparoscopic view of the
      gastro-esophageal junction and angle of His, making the gastrojejunal anastomosis difficult
      to construct. Schwartz et al. support this concept when they found that a large liver was the
      primary reason for conversion from laparoscopic to open RYGBP in an analysis of 1,000
      patients (2).

      A laparoscopic operation consists of making small punctures into the peritoneum, through
      which, a camera and surgical instruments are subsequently inserted. The laparoscopically
      placed camera is the only view of the operative field. Since this point of view is constantly
      changing to meet the surgeon's needs during the operation, and because it is very different
      from the exoscopic view of the surgeon, the surgeon has to be very well trained to interpret
      the images through the laparoscopic view. For LESS operations, a deflectable tip laparoscope
      is utilized in aiding the surgeon for improved visibility and less clashing of instruments.

      The laparoscopic view does not reveal, at one time, all the structures the surgeon needs to
      see in order to complete the surgical procedure with success. These structures can, for
      instance, be hidden behind the peritoneal wall (e.g., the ureter). This limitation cannot
      only lead to a less efficient operation, but can also lead to complications. Often such
      structures can be extracted from preoperative CT/MR images; however, the surgeon needs to
      interpret and fuse these images with the laparoscopic view. To alleviate this problem, we
      propose a laparoscopic visualization scoring system based on the intraoperative quality of
      images (3).

      The impact of muscle relaxants on the isolated abdominal wall or diaphragmatic behavior and
      the absolute intra-abdominal volume are difficult to measure. Conversely, the inflated
      volume-pressure relationship of the abdominal cavity is easier to measure. A description of
      this volume-pressure relationship has not been identified in previous studies. Clinical data
      supports a positive linear correlation between the depth of neuromuscular blockade and
      abdominal wall and diaphragmatic relaxation and compliance (4). There is a very tangible and
      real effect of the neuromuscular blockade; this ultimately has a direct impact on the quality
      of visualization of the surgical field during a laparoscopic procedure (5). A constant
      neuromuscular block leads to preferable working conditions for the surgeon. The evoked muscle
      responses after neurostimulation can be registered by electromyography (EMG),
      mechanomyography (MMG) and acceleromyography (AMG). In principle, different peripheral nerves
      can be used for neurostimulation. The EMG records the electrical signal generated by the
      muscular action potential under its surface electrodes. The force of the thumb after
      stimulation can be registered by MMG. The AMG records the acceleration of the thumb after
      neurostimulation. The EMG, MMG and AMG system allows for observation of the measured signals
      quantity and quality (6).

      We have identified other relevant factors that significantly affect the quality of
      visualization during different laparoscopic procedures including:

        1. Clarity, focus and brightness:

           The laparoscope typically consists of an outer ring of optical fibers used to transmit
           light into the body, and an inner core of rod lenses that illuminate visual scene. This
           is then relayed back to the camera. Various different types of laparoscopes are
           available; they are specified in terms of overall length, number of rods, diameter and
           angle of view. Generally speaking, the wider the scope the brighter the resulting image.
           Lenses are available in the range of 1.9mm to 12mm, but sizes of 5mm and 10mm are the
           most common choices for pediatric and adult patients, respectively.

        2. Breadth of intra-abdominal field and vertical space measured in centimeters:

           Breadth of intra-abdominal field and vertical space are factors directly related to
           pressure insufflation as well as the level of the neuromuscular blockade.

        3. Distracting factors:

           This specific category of distracting factors includes:

             1. Blood: the presence, especially in large quantities, may prevent adequate
                visualization.

             2. Smoke: unipolar electrocautery and/or the bipolar Maryland forceps produce smoke
                when used. The rate of aspiration and evacuation also affect visualization.

             3. Adhesions: the presence of intra-abdominal adhesions, which hinders and prohibits
                proper identification of the anatomic structures.

             4. Sterile iodine impregnated covering sheet: its application presumably has a
                negative impact on abdominal wall and diaphragmatic compliance, and therefore, may
                obscure visualization.

             5. Intra-intestinal air: the presence of air inside the stomach, and small and large
                intestines adversely affects the size of the visual field. This can be prevented by
                an adequate preoperative bowel preparation and placement of an aspiration NG tube
                during anesthesia induction.

        4. Patient's specific factors such as BMI value and body habitus:

           From our experience, a BMI under 26 allows for optimal field visualization. Conversely,
           a BMI greater than 26 negatively impacts the visual field. However, a recent study
           conducted by Camani et al. in 2010 showed that the laparoscopic approach in the various
           applications of gynecologic surgery is not significantly influenced by BMI in terms of
           surgical outcomes, laparotomy conversion rate, intraoperative and postoperative
           complication rate, and duration of hospital stay (4). We feel that visualization during
           operations involving the abdominal cavity are adversely affected by high amounts of
           adipose tissue, and therefore, a visualization scoring system will help support this
           theory.

        5. Type of disorder (malignant vs. benign) that the laparoscopic procedure is undertaken
           for:

           Due to many pathologic factors such as the need for R0 resections, the discovery of more
           advanced disease than anticipated, the presence of adhesions or scar tissue from
           previous operations, laparoscopic procedures for malignant disorders may require a
           better visualization field than laparoscopic procedures undertaken for benign disorders.

        6. Inadequate and/or poorly designed instruments:

           Most laparoscopic instrument development is technology-driven. This approach to
           instrument design does not always consider the ergonomics of the users, therefore
           leading to a user-unfriendly product (4, 5).

        7. Technical difficulties:

           An intraoperative technical difficulty is defined as a significant deviation from the
           ordinary surgical procedure. All conversions to an open operation and iatrogenic bowel
           perforation during laparoscopic surgery are examples of technical difficulties. Many
           studies demonstrate that a technical difficulty during laparoscopic-assisted surgery
           jeopardizes both the intra-operative and postoperative patient safety.

        8. Patient's body position during laparoscopic procedure:

      A study led by Mulier, J et al. in 2010 demonstrated that the Trendelenburg position for
      lower abdominal surgery and reverse Trendelenburg with flexing of the legs at the hips for
      upper abdominal surgery effectively improved the workspace in obese patients, even with full
      muscle relaxation (6).

      II. Objectives A.Primary Objective The primary objective is to develop a laparoscopic
      visualization scoring system.

      B. Secondary Objectives

      The secondary objectives are:

        1. To determine how visualization is affected by various levels of pneumoperitoneum
           correlated with neuromuscular blockade.

        2. Identify the factors that influence visualization, and determine how to manage these
           factors to optimize visualization.

        3. Determine if there is a statistically significant correlation between different degrees
           of visualization and the following intraoperative time intervals:

             1. surgical incision to sterile wound dressing

             2. sterile wound dressing to extubation

             3. sterile wound dressing to patient exiting operating room

        4. Determine if there is a statistically significant correlation between different degrees
           of visualization and postoperative pain.
allocation: N/A
intervention model: Single Group Assignment
primary purpose: Treatment
masking: None (Open Label)
measure: Laparoscopic Visualization Score assessment
time frame: Start to end of LESS Cholecystectomy
measure: pneumoperitoneum volume
time frame: start to end of LESS cholecystectomy
measure: factors influencing visualization
time frame: start to end of LESS cholecystectomy
measure: Degrees of visualization
time frame: start to end of LESS cholecystectomy
description: surgical incision to sterile wound dressing
sterile wound dressing to extubation
sterile wound dressing to patient exiting operating room
measure: postoperative pain
time frame: every day until 7 days after LESS cholecystectomy
arm group label: Cholecystectomy visualization
arm group type: Experimental
description: All patients will undergo a standard single site cholecystectomy and will have their operation recorded and scored for visualization.
intervention type: Other
intervention name: Cholecystectomy visualization
description: Patients undergo a standard removal of the gallbladder through a single incision at the umbilicus will have their operation recorded and graded according to a scale that is established for this study.
arm group label: Cholecystectomy visualization
criteria: 
gender: All
minimum age: 18 Years
maximum age: N/A
healthy volunteers: Accepts Healthy Volunteers
last name: Alexander S. Rosemurgy, MD
role: Principal Investigator
affiliation: Florida Hospital Tampa Bay Division
facility: 
country: United States
citation: Schrenk P, Woisetschlager R, Rieger R, Wayand WU. A diagnostic score to predict the difficulty of a laparoscopic cholecystectomy from preoperative variables. Surg Endosc. 1998 Feb;12(2):148-50. doi: 10.1007/s004649900616.
PMID: 9479730
citation: Nguyen NT, Longoria M, Gelfand DV, Sabio A, Wilson SE. Staged laparoscopic Roux-en-Y: a novel two-stage bariatric operation as an alternative in the super-obese with massively enlarged liver. Obes Surg. 2005 Aug;15(7):1077-81. doi: 10.1381/0960892054621062.
PMID: 16105411
citation: Stijn de Buck, Johan van Cleynenbreugel, Indra Geys, Thomas Koninckx, Philippe R Koninck, Paul Suetens. A System to Support Laparoscopic Surgery by Augmented Reality Visualization. Medical Image Computing and Computer-Assisted Intervention; 691-8, 2001.
citation: Camanni M, Bonino L, Delpiano EM, Migliaretti G, Berchialla P, Deltetto F. Laparoscopy and body mass index: feasibility and outcome in obese patients treated for gynecologic diseases. J Minim Invasive Gynecol. 2010 Sep-Oct;17(5):576-82. doi: 10.1016/j.jmig.2010.04.002. Epub 2010 Jul 8.
PMID: 20619751
citation: McDougall EM, Figenshau RS, Clayman RV, Monk TG, Smith DS. Laparoscopic pneumoperitoneum: impact of body habitus. J Laparoendosc Surg. 1994 Dec;4(6):385-91. doi: 10.1089/lps.1994.4.385.
PMID: 7881141
citation: Mulier JP, Dillemans B, Van Cauwenberge S. Impact of the patient's body position on the intraabdominal workspace during laparoscopic surgery. Surg Endosc. 2010 Jun;24(6):1398-402. doi: 10.1007/s00464-009-0785-8. Epub 2010 Jan 7.
PMID: 20054583
citation: Simanski , R. Kahler, B. Pohl, R. Hofmockel, R. Friedrich, B. P. Lampe Measurement and control of neuromuscular blockade and depth of anaesthesia. Proceedings of the European Control Conference, Cambridge/UK. 2003.
responsible party type: Principal Investigator
investigator affiliation: Florida Hospital Tampa Bay Division
investigator full name: Alexander Rosemurgy
investigator title: Director HPB Surgery, GERD Center
mesh term: Cholecystitis
sharing ipd: No