-
The Journal of Urology Jun 1977
Topics: Humans; Phenoxybenzamine; Urinary Bladder, Neurogenic
PubMed: 875171
DOI: 10.1016/s0022-5347(17)58643-7 -
Anesthesia and Analgesia Aug 2007Perioperative management of neonates after the Norwood procedure is extremely complex. Limited reserve of the neonatal single ventricle and the parallel arrangement of... (Review)
Review
Perioperative management of neonates after the Norwood procedure is extremely complex. Limited reserve of the neonatal single ventricle and the parallel arrangement of the pulmonary and systemic circuits result in a tenuous balance between pulmonary and systemic blood flows. Precise manipulations of both pulmonary and systemic vascular resistance are necessary to prevent excessive pulmonary blood flow at the expense of systemic oxygen delivery. An emerging treatment strategy aimed at improving early mortality is the intraoperative administration of phenoxybenzamine, a profound systemic vasodilator. Maximum systemic vasodilation is thought to reduce afterload of the single ventricle and produce a more stable parallel circulation by ameliorating the postoperative fluctuations in systemic vascular resistance. Although this strategy has gained popularity at many centers, it is not without scrutiny. The following review provides an overview of the pharmacology of phenoxybenzamine, the surgical and physiologic implications of the Norwood procedure, and a discussion of the pros and cons of phenoxybenzamine administration.
Topics: Cardiopulmonary Bypass; Humans; Hypoplastic Left Heart Syndrome; Infant, Newborn; Monitoring, Intraoperative; Phenoxybenzamine; Pulmonary Circulation
PubMed: 17646482
DOI: 10.1213/01.ane.0000275185.44796.92 -
The Netherlands Journal of Medicine May 2014During surgical treatment of pheochromocytoma,`haemodynamic instability may occur. To prevent this, patients receive preoperative treatment with an alpha-blocker.... (Review)
Review
BACKGROUND
During surgical treatment of pheochromocytoma,`haemodynamic instability may occur. To prevent this, patients receive preoperative treatment with an alpha-blocker. Nowadays, some centres use phenoxybenzamine, while others use doxazosin. The purpose of this review is to analyse the current evidence of the benefits and risks of phenoxybenzamine and doxazosin in the preoperative treatment of pheochromocytoma.
METHODS
The literature was reviewed by searching PubMed using the following search terms: pheochromocytoma, phenoxybenzamine, doxazosin and alpha-blockade. The filter was set on English language.
RESULTS
No randomised controlled trials were found. Five follow-up studies comparing phenoxybenzamine and doxazosin in the treatment of pheochromocytoma were retrieved and analysed. There was a trend that systolic arterial pressure is slightly better controlled by phenoxybenzamine. However, this resulted in more pronounced postoperative hypotension as well. The use of an alpha-blocker was often accompanied by other vasoactive agents. phenoxybenzamine was often accompanied by a beta-blocker to control reflex tachycardia, while patients on doxazosin received significantly more additional antihypertensive medicines. Most of the studies showed that the use of vasoactive drugs and fluid infusion does not differ significantly between the two drugs. Phenoxybenzamine caused significantly more orthostatic hypotension, oedema and complaints of a stuffy nose.
CONCLUSION
On the basis of the current evidence, there is no evidently superior alpha-blocker for the pretreatment of patients with pheochromocytoma. Perioperative haemodynamics seem to be slightly better controlled with phenoxybenzamine, at the cost of more pronounced postoperative hypotension. Side effects occurred less often in the doxazosin group.
Topics: Adrenal Gland Neoplasms; Adrenergic alpha-1 Receptor Antagonists; Adrenergic alpha-Antagonists; Blood Pressure; Doxazosin; Humans; Phenoxybenzamine; Pheochromocytoma; Preoperative Care
PubMed: 24829175
DOI: No ID Found -
IARC Monographs on the Evaluation of... 1975
Review
Topics: Animals; Carcinogens; Drug Evaluation, Preclinical; Female; Guinea Pigs; Humans; Lethal Dose 50; Lung Neoplasms; Male; Mice; Phenoxybenzamine; Rats; Sex Factors; Species Specificity
PubMed: 791836
DOI: No ID Found -
Report on Carcinogens : Carcinogen... 2011
Topics: Animals; Antihypertensive Agents; Carcinogens; Humans; Neoplasms; Phenoxybenzamine; Vasodilator Agents
PubMed: 21863081
DOI: No ID Found -
Urologia Internationalis 1984A short controlled trial has confirmed that phenoxybenzamine (10 or 20 mg/day) relaxes the resting proximal urethra and reduces the voiding frequency in patients with... (Clinical Trial)
Clinical Trial Randomized Controlled Trial
A short controlled trial has confirmed that phenoxybenzamine (10 or 20 mg/day) relaxes the resting proximal urethra and reduces the voiding frequency in patients with benign prostatic hypertrophy.
Topics: Aged; Double-Blind Method; Drug Evaluation; Humans; Male; Middle Aged; Phenoxybenzamine; Pressure; Prostatic Hyperplasia; Random Allocation
PubMed: 6207651
DOI: 10.1159/000280984 -
The Journal of Clinical Endocrinology... Jul 2020Pretreatment with α-adrenergic receptor blockers is recommended to prevent hemodynamic instability during resection of a pheochromocytoma or sympathetic paraganglioma... (Randomized Controlled Trial)
Randomized Controlled Trial
CONTEXT
Pretreatment with α-adrenergic receptor blockers is recommended to prevent hemodynamic instability during resection of a pheochromocytoma or sympathetic paraganglioma (PPGL).
OBJECTIVE
To determine which type of α-adrenergic receptor blocker provides the best efficacy.
DESIGN
Randomized controlled open-label trial (PRESCRIPT; ClinicalTrials.gov NCT01379898).
SETTING
Multicenter study including 9 centers in The Netherlands.
PATIENTS
134 patients with nonmetastatic PPGL.
INTERVENTION
Phenoxybenzamine or doxazosin starting 2 to 3 weeks before surgery using a blood pressure targeted titration schedule. Intraoperative hemodynamic management was standardized.
MAIN OUTCOME MEASURES
Primary efficacy endpoint was the cumulative intraoperative time outside the blood pressure target range (ie, SBP >160 mmHg or MAP <60 mmHg) expressed as a percentage of total surgical procedure time. Secondary efficacy endpoint was the value on a hemodynamic instability score.
RESULTS
Median cumulative time outside blood pressure targets was 11.1% (interquartile range [IQR]: 4.3-20.6] in the phenoxybenzamine group compared to 12.2% (5.3-20.2)] in the doxazosin group (P = .75, r = 0.03). The hemodynamic instability score was 38.0 (28.8-58.0) and 50.0 (35.3-63.8) in the phenoxybenzamine and doxazosin group, respectively (P = .02, r = 0.20). The 30-day cardiovascular complication rate was 8.8% and 6.9% in the phenoxybenzamine and doxazosin group, respectively (P = .68). There was no mortality after 30 days.
CONCLUSIONS
The duration of blood pressure outside the target range during resection of a PPGL was not different after preoperative treatment with either phenoxybenzamine or doxazosin. Phenoxybenzamine was more effective in preventing intraoperative hemodynamic instability, but it could not be established whether this was associated with a better clinical outcome.
Topics: Adrenal Gland Neoplasms; Adrenergic alpha-Antagonists; Blood Pressure; Doxazosin; Female; Humans; Male; Middle Aged; Phenoxybenzamine; Pheochromocytoma; Treatment Outcome
PubMed: 31714582
DOI: 10.1210/clinem/dgz188 -
International Journal of Molecular... Jan 2014Phenoxybenzamine (PBZ) is an FDA approved α-1 adrenergic receptor antagonist that is currently used to treat symptoms of pheochromocytoma. However, it has not been...
Phenoxybenzamine (PBZ) is an FDA approved α-1 adrenergic receptor antagonist that is currently used to treat symptoms of pheochromocytoma. However, it has not been studied as a neuroprotective agent for traumatic brain injury (TBI). While screening neuroprotective candidates, we found that phenoxybenzamine reduced neuronal death in rat hippocampal slice cultures following exposure to oxygen glucose deprivation (OGD). Using this system, we found that phenoxybenzamine reduced neuronal death over a broad dose range (0.1 µM-1 mM) and provided efficacy when delivered up to 16 h post-OGD. We further tested phenoxybenzamine in the rat lateral fluid percussion model of TBI. When administered 8 h after TBI, phenoxybenzamine improved neurological severity scoring and foot fault assessments. At 25 days post injury, phenoxybenzamine treated TBI animals also showed a significant improvement in both learning and memory compared to saline treated controls. We further examined gene expression changes within the cortex following TBI. At 32 h post-TBI phenoxybenzamine treated animals had significantly lower expression of pro-inflammatory signaling proteins CCL2, IL1β, and MyD88, suggesting that phenoxybenzamine may exert a neuroprotective effect by reducing neuroinflammation after TBI. These data suggest that phenonxybenzamine may have application in the treatment of TBI.
Topics: Animals; Brain; Brain Injuries; Cell Death; Cell Survival; Cells, Cultured; Chemokine CCL2; Drug Evaluation, Preclinical; Interleukin-1beta; Maze Learning; Memory; Myeloid Differentiation Factor 88; Neurons; Neuroprotective Agents; Phenoxybenzamine; Rats; Rats, Sprague-Dawley
PubMed: 24447929
DOI: 10.3390/ijms15011402 -
IARC Monographs on the Evaluation of... 1980
Review
Topics: Animals; Chemical Phenomena; Chemistry; Female; Humans; Male; Mice; Mutagenicity Tests; Neoplasms, Experimental; Phenoxybenzamine; Rats; Teratogens; Terminology as Topic
PubMed: 7009392
DOI: No ID Found -
Anesthesia and Analgesia Aug 2007
Topics: Cardiopulmonary Bypass; Humans; Hypoplastic Left Heart Syndrome; Phenoxybenzamine
PubMed: 17646481
DOI: 10.1213/01.ane.0000278952.27339.74