What happens during the surgical procedure?

FOUR  different medical and surgical teams are involved in a pituitary surgery

1. Anesthesia team:
   1. Assess patients’ history and airway prior to giving sedation and anesthesia
   2. Manage fluid administration during the operation: An intravenous catheter is placed in veins to give fluids, medicines and to take blood samples
   3. Manage patient breathing by placing a breathing tube, usually through the mouth, that attaches to a breathing machine while the patient is asleep.
   4. The anesthesia team monitors the patient’s vital signs, heart rate, blood pressure, blood electrolyte levels and more throughout the procedure and during the recovery period.
2. The Ear, Nose and Throat (ENT) team:
   1. Once the patient is under anesthesia, the ENT surgeon makes an incision inside one side of the nose. They remove tissue and bone to open a small hole into the pituitary sella (the protected bone around the pituitary).
   2. At the end of the surgery ENT surgeons ‘sew up’ or close any wounds in the nose. They may place surgical packing in the nose that may need to be removed from several days to 1-2 weeks after surgery.
      
   3. Neurosurgery team:
      1. Place either a special endoscope or microscope tube through the side of nose to see and remove the tumour.An endoscope is a thin tube with a high-powered camera and light at the end through which small instruments can be advanced.  The camera view is also projected onto a large TV screen for viewing by the surgical team.If a microscope is used, it’s attached to an endoscope. the surgeon looks through the microscope to view the surgical area.
      2. Use special instruments and suction tube through the endoscope to remove tumour, tissue samples and blood. The tumor is usually removed in pieces small enough to pass through the suction device. As much of the tumor as possible is preserved for the pathologist to examine usually after the surgery.
      3. Sometimes an imaging or MRI technique is used to help the surgeon navigate more exactly to the location of the tumor.
      4. When all the visible tumour is removed, the area is assessed for any leakage of cerebrospinal fluid. The hole in the bone underneath the pituitary is then filled with either a surgical packing material or a small amount of the patients’ own fat tissue that is taken from just under the skin, most often of the abdomen. If a cerebrospinal fluid (CSF) leak is found, the anesthesia team will place a small catheter into the spinal canal in the lower back to keep the pressure in the spinal column low and allow the leak to heal.  This is usually removed around 72 hours after surgery.
      5. After surgery, patients are observed in hospital for 1-3 days for: Cerebrospinal fluid leak, headaches, need for pain medication, vision changes, fluid balance ( liquid consumed and the volume of urine each day).  Blood is tested for sodium levels frequently.
      6. 

The Endoscope is placed in the nostril and the bony sella floor is removed.

4. Endocrine team
   Patients are monitored for symptoms of several pituitary hormone deficiencies.
   1. Adrenal insufficiency (AI) or failure of pituitary adrenocorticotropic hormone (ACTH) to stimulate the adrenal glands.
      Symptoms of AI include headaches, nausea, dizziness, and vomiting.  It’s notable that headaches are not uncommon after this surgery.  Glucocorticoid replacement medications, such as hydrocortisone, will be given if needed or in some centers until the ability of the adrenal glands to produce cortisol can be tested around 12-14 days after surgery.
   2. Patients are monitored for arginine vasopressin deficiency /diabetes insipidus. This includes:
      a. Regular blood draws for sodium levels (high sodium);
      b. Blood and urine testing for osmolality (concentration);
      c. The total amount of fluid taken in and the volume of urine out;
      d. Patient’s thirst and how frequently they are urinating during the day and at night.

      Treatment with medication such as vasopressin or desmopressin may be given if needed.

   3. After discharge blood electrolytes will be monitored for the development of Syndrome of Inappropriate Anti-diuretic Hormone (SIADH) or low sodium. Patients and family are instructed to monitor for changes in mental state such as confusion and notify the endocrine team.
   4. If hormone excess is known before surgery blood levels of cortisol, ACTH, growth hormone (IGF-1) levels or prolactin levels may also be checked immediately post operatively.