CT MYELOGRAPHY DOSAGES

Omnipaque 180 (180 mgI/mL)

Lumbar Myelography, via lumbar injection 10-17 mL
Cervical Myelography, via C1-C2 injection: 7-12.5 mL

Omnipaque 240 (240 mgI/mL)

Lumbar Myelography, via lumbar injection: 7-12.5 mL
Thoracic Myelography, via lumber/cervical injection: 6-12.5 mL
Cervical Myelography, via lumbar injection: 6-12.5 mL; via C1-C2 injection: 6-12.5
Total Columnar Myelography, via lumbar injection: 6-12.5 mL

Omnipaque 300 (300 mgI/mL)

Thoracic Myelography, via lumbar/cervical injection: 6-10 mL
Cervical Myelography, via lumbar injection: 6-10 mL; via C1-C2 injection: 4-10 mL
Total Columnar Myelography, via lumbar injection: 6-10 mL

Administration
Rate of injection: Slowly over 1-2 min
Not to exceed 300 mg/mL or 3060 mg iodine per single myelographic procedure

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ANAPHYLACTOID REACTION

HYPOTENSION (SBP<80 mm Hg) + TACHYCARDIA (HR>100 pm) +/-dizziness +/-diaphoresis +/-loss of consciousness

Elevate legs > 60 degrees OR Trendelenburg position.
Administer O2 6 -10 L/min via mask.
Monitor: EKG, BP, HR
Administer NS or RL rapid IV.
If still not responding or poor response: IV epinephrine 1 mL (1:10,000) slow push.
Repeat as needed to a max. of 1 mg If still not responding or poor response: Call for help

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PREMEDICATION REGIMENS

ELECTIVE PREMEDICATION

1. Prednisone – 50 mg by mouth at 13 hours, 7 hours, and 1 hour before contrast media injection, plus Diphenhydramine (Benadryl®) – 50 mg intravenously, intramuscularly, or by mouth 1 hour before contrast medium.

2. Methylprednisolone (Medrol®) – 32 mg by mouth 12 hours and 2 hours before contrast media injection plus Diphenhydramine (Benadryl®) – 50 mg intravenously, intramuscularly, or by mouth 1 hour before contrast medium. If the patient is unable to take oral medication, 200 mg of hydrocortisone intravenously may be substituted for oral prednisone.

EMERGENCY PREMEDICATION

[In Decreasing Order of Preference]

1. Methylprednisolone sodium succinate (Solu-Medrol®) 40 mg or hydrocortisone sodium succinate (Solu-Cortef®) 200 mg intravenously every 4 hours until contrast study required plus diphenhydramine 50 mg IV 1 hour prior to contrast injection.

2. Dexamethasone sodium sulfate (Decadron®) 7.5 mg or betamethasone 6.0 mg intravenously q4h until contrast study in patent with known allergy to methylprednisolone, aspirin, or non-steroidal anti-inflammatory drugs, especially if asthmatic. Also diphenhydramine 50 mg IV 1 hour prior to contrast injection.

3. Omit steroids entirely and give diphenhydramine 50 mg IV.