Prevention or control of hypertensive episodes in the patient with pheochromocytoma
- Preoperative: 5 mg IM/IV 1-2 hrs prior to surgery. Dose may be repeated if required
- During surgery: 5 mg IV as indicated
Prevention or treatment of dermal necrosis and sloughing following intravenous administration or extravasation of norepinephrine
- For prevention: Add 10 mg of phentolamine to 1 L of solution containing norepinephrine
- For Treatment: 5-10 mg of phentolamine mesylate in 10 mL of saline is injected into the area of extravasation within 12 hrs
Diagnosis of pheochromocytoma - phentolamine blocking test
- 5 mg IV dissolved in 1 mL of sterile water for injection
- Record BP immediately after injection, at 30 sec intervals for the first 3 mins, and at 60-sec intervals for the next 7 mins
- Note that expected result consistent with pheochromocytoma is a 60 mmHg SBP and 25 mmHg DBP drop in 2 mins, with recovery of the pre-treatment blood pressure usually within 15-30 mins
- 5 mg IM dissolved in 1 mL of sterile water for injection
- Record BP every 5 mins for 30-45 mins following injection
- Note that expected result consistent with pheochromocytoma is a 35 mmHg SBP and 25 mmHg DBP drop or more within 20 minutes
Reversal of the soft-tissue anesthesia with vasoconstrictor
- 0.2-0.8 mg given as a submucosal injection based on the amount of local anesthetic
Hypertensive Emergency [Non-FDA approved]
- 5-15 mg IV bolus
Prevention or control of hypertensive episodes in the patient with pheochromocytoma
- Preoperative: 1 mg IM/IV 1-2 hrs prior to surgery. Dose may be repeated if required
- During surgery: 1 mg IV as indicated
Diagnosis of pheochromocytoma - phentolamine blocking test
- 1 mg IV dissolved in 1 mL of sterile water for injection
- Record BP immediately after injection, at 30-sec intervals for the first 3 mins, and at 60-sec intervals for the next 7 mins
- Note that expected result consistent with pheochromocytoma is a 60 mmHg SBP and 25 mmHg DBP drop in 2 mins, with recovery of the pre-treatment blood pressure usually within 15-30 mins
- 3 mg IM dissolved in 1 mL of sterile water for injection
- Record BP every 5 mins for 30 to 45 mins following injection
- Note that expected result consistent with pheochromocytoma is a 35 mmHg SBP and 25 mmHg DBP drop or more within 20 mins
Reversal of soft-tissue anesthesia with vasoconstrictor
- Child 6-12 yrs/ 15-30 kg: Dose given is based on the amount of local anesthetic. Max dose 0.2 mg submucosal injection
