PET Scan

Key Points:

  1. The radioactive isotope must be given IV and the patient must wait 1 hr before starting the scan. They should be minimally active and euthermic during this time.

  2. Isotope uptake can be adversely affected by premedication agents like benzodiazepines or ketamine. Nasal Precedex is the premedication with the least impact on isotope uptake.


General:

  • PET Scan is used for Tumor Surveillance. It utilizes a radioactive isotope that is metabolized like glucose. This concentrates in metabolically active parts of the body and can be used to identify tumors.


Location:

  • Adult tower basement. Follow signs for MRI à take second set of double doors for MRI (on your right) à double doors on left has sign for PET/CT à on the left are the two preop rooms and on the right is the scanner and control room where you will chart.


Flow:

  • You will not be able to enter the scanner until 0630 (PET technicians have check machine).

  • The time the case is posted is the time the medication is to be administered by technicians. It is important to interview the patient before the IV is obtained and the radioisotope is given to ensure anesthesia is not canceling the case and anesthesia consent (done by anesthesiologist) is obtained.

  • Many patients have either a port or PICC line, some require PIV access.

    • Pre-medication with Nasal Precedex (2-4 mcg/kg) may be required for IV/Port access. Time to peak effect is ~45 min.

  • The patient should be asleep in the scanner exactly 1 hour after isotope dose is given. Need to know if the patient is going to get a CT in addition to the PET scan.

    • If no CT, the patient should be brought into the scanner ~35 min after medication given.

    • If CT is planned, the patient should be brought into the scanner ~20 min after medication to be put to sleep and have the CT done at 45 min so the PET scan can start at the 1 hour mark. Error on the side of giving yourself more time.

    • It is imperative to have good communication between the CRNA, anesthesiologist and tech for timing the medications.

    • i.e. Case posted at 0700. Patient to arrive at 0630. Anesthesiologist to see patient to obtain consent and ensure patient will not be canceled. Port accessed. Medication administered by technician at 0700. Pt brought to scanner at 0725 by tech. Pt asleep and CT started at 0745 with PET scan to follow at 0800.

  • Adult anesthesia tech will bring down peds cart but allow enough time to go upstairs for missing supplies.

  • Chart in centricity in control room.

    • Password for computer is 3-4 ID.

    • Helpful hint: After induction/emergence prior to leaving scanner, take a picture of VS to chart.


Set up:

  • 5-10 mL propofol bolus syringe

  • 20-50 mL propofol on pump (with extension tubing)

  • 500 mL LR with microdrip/buretrol + extension with port closest to IV site for CT contrast

  • Peds face mask

  • O2 extension tubing with connector (in brown cabinet labeled O2, on opposite wall as anesthesia machine)

  • 2 EtCO2 connector with 3 way stop cock

  • Circuit extension

  • Some anesthesiologists may opt for LMA and volatile anesthetic.

  • Shoulder roll (if needed for airway patency)

  • Emergency drugs: Epi, succinylcholine, and atropine + IM needles + flush

  • Emergency airway: appropriate sized ETTs, LMA, and oral airway


Preoperative:

  • Tests- as indicated per H&P

  • Premedication- avoid benzos and ketamine. Nasal Precedex (2-4 mcg/kg) is preferred if premedication is required. Time to peak effect is ~45 min.

  • Ask the technician if any need for breath holding. ETT with paralysis may be needed.


Intraoperative:

  • Anesthetic technique- general with native airway

  • Position- supine with arms at side

  • Surgical time- 1 h

  • Blood and fluid requirements

    • IV: 1 PIV

  • Standard monitoring

  • Induction

    • Bolus propofol + start infusion at 200 mcg/kg/min and titrate.

    • Ensure patent airway.

    • Check IV fluid running appropriately before leaving scanner.

  • Maintenance

    • May enter room during PET scan to set up for next case but not during CT portion.

    • After tech administers medication during scan, ensure propofol is still running.

  • Emergence

    • PET Scan nurses may not be experienced with peds patients, strongly consider emerging the patient prior to transferring care.


Postoperative:

  • Recover patient in MRI then phase II back in preop holding.