Evaluation of the Effect of Trendelenburg Position Duration on Intracranial Pressure
Condition: Intracranial Pressure Increase
MeSH terms: Intracranial Hypertension
Study type: Interventional

Summary: 
      The Lloyd Davies position is a position used in laparoscopic hysterectomies where the head is
      lowered 45 degrees and the legs are bent from the knee area.It is a version of the
      Trendelenburg position. Both this position and for laparoscopic surgery carbon dioxide (CO2)
      gas given into the abdomen, causes problems for the patient. Increased abdominal and thoracic
      pressure impairs venous return and increases intracranial pressure. Optic nerve sheath
      diameter can be measured by placing an ultrasound probe over the eye. It is possible to
      follow up the increase in intracranial pressure with this diameter measurement. In this
      study, it was planned to measure the optic nerve sheath diameter by ultrasound in patients
      who will undergo laparoscopic hysterectomy. It is aimed to observe the changes in the
      increase in intracranial pressure as the time lengthens with the measurements to be made at
      certain intervals during the operation. Secondary aim is to determine whether there is a
      cut-off value where the intracranial pressure starts to increase.
    

Detailed description: 
      The Trendelenburg position is the patient's head down with the table tilted, with the head
      closer to the floor than the feet. Lloyd Davies position is a modified version of the
      Trendelenburg position, used especially in laparoscopic hysterectomies, where the head is
      lowered 30-45° and the legs are bent at knee level. During this surgery, pneumoperitoneum is
      also applied by administering carbon dioxide (CO2) into the abdomen. During this surgery,
      pneumoperitoneum is also applied by administering CO2 into the abdomen. The applied position
      and intra-abdominal CO2 cause some physiological changes. These changes include respiratory
      and cardiac changes as well as increased intracranial pressure. Optic nerve sheath diameter
      can be measured by placing an ultrasound probe over the eye. Increase in intracranial
      pressure can be followed by sequential measurements. In this study, it was planned to measure
      the optic nerve sheath diameter by ultrasound in patients who will undergo laparoscopic
      hysterectomy. It is aimed to observe the changes in the increase in intracranial pressure as
      the time lengthens with the measurements to be made at certain intervals during the
      operation. Before the patients were given anesthesia induction, optic nerve sheath diameter
      measurement (ONSD) was performed by imaging in the sagittal and transverse planes in both
      eyes in neutral position. The second measurement was taken 2 minutes after endotracheal
      intubation in the neutral position. After the trocars were placed and pneumoperitoneum was
      applied, the patient was placed in the Lloyd Davies position. After the position was given,
      bilateral ONSD measurements were taken at the 30th minute, 60th minute, 75th minute, and 90th
      minute. At the end of the surgery, pneumoperitoneum and position were neutralized. The last
      measurement was taken 5 minutes after the patient was placed in the neutral position. Near
      infrared spectrometry (NIRS) monitoring was performed throughout the surgery.
    

Intervention name(s): ultrasound guided optic nerve sheath diameter measurement
Intervention type(s): Device
Intervention description(s): First, both eyes were measured in a neutral position while awake and after intubation. Measurements were made at regular intervals until the end of the operation after the head-down position and in the neutral position after the operation.
Intervention model: Single Group Assignment
Intervention model description: In patients in head-down position who will undergo laparoscopic hysterectomy, it is planned to measure the optic nerve sheath diameter with ultrasound at the beginning and at certain periods of the surgery.
Masking: None (Open Label)
Primary purpose: Screening
Keywords: optic nerve sheath diameter measurement; trendelenburg position; laparoscopic hysterectomy