ONSD According to the Position During Laparoscopy
Condition: Cholecystitis; Ovarian Cyst; Ovarian Cancer; Uterine Myoma; Cervical Cancer
MeSH terms: Ovarian Cysts; Leiomyoma; Myofibroma; Cholecystitis
Study type: Interventional

Summary: 
      Increase of intracerebral pressure (ICP) during laparoscopic surgery has known to be
      associated with positional changes. Optic nerve sheath diameter (ONSD) has correlation with
      ICP and ultrasonographic measurement of optic nerve sheath diameter (ONSD) is known to be a
      noninvasive and rapidly applicable technique for evaluating ICP. The aim of this study is to
      investigate the change of ONSD according to the positional change during laparoscopic
      surgery.
    

Detailed description: 
      1. Purpose There can be many physiologic changes during laparoscopic surgery. Increase of
           intracerebral pressure (ICP) is one of them, which has known to be associated with
           arterial concentration of carbon dioxide or positional changes. Changes of ICP can be
           measured directly by invasive method. However, optic nerve sheath diameter (ONSD) has
           correlation with ICP and ultrasonographic measurement of optic nerve sheath diameter
           (ONSD) is known to be a noninvasive and rapidly applicable technique for evaluating ICP.
           The aim of this study is to investigate the change of ONSD according to the positional
           change during laparoscopic surgery.

        2. Hypothesis Changes of ONSD will be shown according to the positional change during
           laparoscopic surgery, and these can reflect the changes of ICP.

        3. Objectives Female patients who are scheduled to undergo laparoscopic surgery, American
           society of anesthesiologist class (ASA) I-II, aged between 19 to 65 years, are allocated
           into 2 groups.

             -  Group 1: Laparoscopic gynecological surgery, (Trendelenburg position)

             -  Group 2: Laparoscopic cholecystectomy, (Reverse trendelenburg position)

        4. Methods Patients are premedicated with midazolam 0.5 mg/kg before transported to the
           operating room. Once in the operating room, patients were monitored with
           electrocardiography, non invasive blood pressure, pulse oximetry (Datex-Ohmeda S/5,
           Planar Systems, Inc., Beaverton, OR, USA) and BIS (Aspect 2000, Aspect Medical Systems,
           Inc., Newton, MA, USA).

           Anesthesia are induced with propofol (2mg/kg) and followed by administering rocuronium
           0.6 mg/kg. After tracheal intubation, the lungs of the patients were then ventilated
           with oxygen in air (1:2) using a tidal volume of 8-10 mL/kg and a respiratory rate of
           10-12/min, and the ventilation rate was adjusted to maintain the end-tidal carbon
           dioxide partial pressure between 35 and 40 mmHg and peak inspiratory pressure below 30
           cmH2O. Anesthesia is maintained with desflurane in addition to the continuous infusion
           of remifentanil. Radial arterial cannulation is done for invasive arterial blood
           pressure monitoring.

           After induction of anesthesia, when stabilization of cardiovascular status is achieved,
           optic nerve sheath diameter (ONSD) is measured by ultrasonographic measurement. Patients
           were placed in the supine position with their eyes closed, and a thick gel layer was
           applied to the closed upper eyelid. The 7.5-MHz linear probe was placed on the gel
           without excessive pressure and adjusted to the proper angle for displaying the entry of
           the optic nerve into the globe. The intensity of the ultrasound was adjusted to display
           optimal contrast between the retrobulbar echogenic fat tissue and the vertical
           hypoechoic band. An ultrasound beam was focused on the retrobulbar area (4 cm deep)
           using the lowest possible acoustic power that could measure ONSD. The ONSD was measured
           3 mm behind the optic disc. Measurements were performed in the transverse and sagittal
           planes of both eyes, and the final ONSD value was calculated by averaging 4 measured
           values.

           ONSD was measured at 7 serial time points during surgery:

             1. Preinduction (prior to the induction of anesthesia in the operating room)

             2. 5 minutes after induction of anesthesia

             3. 5 minutes after introducing pneumoperitoneum

             4. 5 minutes after positional change

             5. 15 minutes after positional change

             6. 30 minutes after positional change

             7. 5 minutes after discontinuing pneumoperitoneum Arterial blood gas analysis is
                performed to evaluate the arterial carbon dioxide concentration (PaCO2) level at
                each time point.

        5. Statistical Analysis All data are expressed as numbers (%) or mean ± standard deviation.
           Repeated measures ANOVA will be performed to compare the parameters at specific time
           points during surgery.
    

Intervention name(s): Desflurane; Remifentanil; Ultrasonographic measurement of ONSD; Mechanical ventilation; Trendelenburg position - 30 degree; Reverse Trendelenburg position - 30 degree
Intervention type(s): Drug; Drug; Device; Procedure; Procedure; Procedure
Intervention description(s): Anesthesia with desflurane in both Group 1 and Group 2
- adjust MAC to maintain BIS between 40-60; Adjuvant continuous administration
- adjust effect site concentration to maintain changes of vital sign below 20%; Patients were placed in the supine position with their eyes closed, and a thick gel layer was applied to the closed upper eyelid. The 7.5-MHz linear probe was placed on the gel without excessive pressure and adjusted to the proper angle for displaying the entry of the optic nerve into the globe. The intensity of the ultrasound was adjusted to display optimal contrast between the retrobulbar echogenic fat tissue and the vertical hypoechoic band. An ultrasound beam was focused on the retrobulbar area (4 cm deep) using the lowest possible acoustic power that could measure ONSD. The ONSD was measured 3 mm behind the optic disc. Measurements were performed in the transverse and sagittal planes of both eyes, and the final ONSD value was calculated by averaging 4 measured values.; After tracheal intubation, the lungs of the patients were then ventilated with oxygen in air (1:2) using a tidal volume of 8-10 mL/kg and a respiratory rate of 10-12/min, and the ventilation rate was adjusted to maintain the end-tidal carbon dioxide partial pressure between 35 and 40 mmHg and peak inspiratory pressure below 30 cmH2O.; Trendelenburg position - 30 degree; Reverse Trendelenburg position - 30 degree
Other intervention name(s): Ultiva
Intervention MeSH terms: Remifentanil; Desflurane
Allocation: Non-Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Diagnostic
Keywords: Intracranial pressure; Laparoscopy; Optic nerve sheath diameter; Position