Endocrine effects of dopexamine vs. dopamine in high-risk surgical patients

Clinical prevalence and outcome impact of pituitary dysfunction after aneurysmal subarachnoid hemorrhage: a systematic review with meta-analysis

PURPOSE

Pituitary dysfunction is reported to be a common complication following aneurysmal subarachnoid hemorrhage (aSAH). The aim of this meta-analysis is to analyze the literature on clinical prevalence, risk factors and outcome impact of pituitary dysfunction after aSAH, and to assess the possible need for pituitary screening in aSAH patients.

METHODS

We performed a systematic review with meta-analysis based on a comprehensive search of four databases (PubMed/MEDLINE, ISI/Web of Science, Scopus and Google Scholar).

RESULTS

A total of 20 papers met criteria for inclusion. The prevalence of pituitary dysfunction in the acute phase (within the first 6 months after aSAH) was 49.30 % (95 % CI 41.6-56.9), decreasing in the chronic phase (after 6 months from aSAH) to 25.6 % (95 % CI 18.0-35.1). Abnormalities in basal hormonal levels were more frequent when compared to induction tests, and the prevalence of a single pituitary hormone dysregulation was more frequent than multiple pituitary hormone dysregulation. Increasing age was associated with a lower prevalence of endocrine dysfunction in the acute phase, and surgical treatment of the aneurysm (clipping) was related to a higher prevalence of single hormone dysfunction. The prevalence of pituitary dysfunction did not correlate with the outcome of the patient.

CONCLUSIONS

Neuroendocrine dysfunction is common after aSAH, but these abnormalities have not been shown to consistently impact outcome in the data available. There is a need for well-designed prospective studies to more precisely assess the incidence, clinical course, and outcome impact of pituitary dysfunction after aSAH.

Effects of dopexamine, dobutamine or dopamine on prolactin and thyreotropin serum concentrations in high-risk surgical patients

OBJECTIVES

Catecholamines are often used for optimisation of cardiac index and oxygen delivery in high-risk surgical patients; however, infusions of dopamine and dopexamine are associated with dose-dependent hypophysiotropic and thyreotropic properties. The objective was to compare endocrine effects of equipotent inotropic doses of dopexamine, dobutamine and dopamine on prolactin and thyreotropin release perioperatively.

DESIGN

A prospective, randomised, blinded clinical trial.

SETTING

Adult surgical intensive care unit in a university hospital.

PATIENTS

Thirty male patients (ASA III) undergoing elective major abdominal surgery.

INTERVENTIONS

Patients were randomised to receive dopexamine (DX, n=10), dobutamine (DO, n=10) or dopamine (DA, n=10) on the first postoperative day for 8 h.

MEASUREMENTS AND RESULTS

All patients received a catecholamine infusion in doses adjusted to increase cardiac index by 35% within the first hour. Blood samples were obtained and prolactin and thyreotropin serum concentrations were determined by radioimmunoassays. Mean doses of dopexamine, dobutamine and dopamine used were 0.73+/-0.27, 4.06+/-1.95 and 5.0+/-1.84 micro g kg(-1)min(-1), respectively. Cardiac index was increased by 36% (DX group), 38% (DO group) and 38% (DA group). Alterations of oxygen delivery and oxygen consumption were not significantly different between the study groups. Dopexamine and dobutamine had no hypophysiotropic effects. In contrast, dopamine suppressed prolactin and thyreotropin secretion with a maximal effect after 4 h. After dopamine withdrawal, a rebound release of prolactin and thyreotropin was observed.

CONCLUSIONS

In high-risk surgical patients dopexamine or dobutamine produced fewer effects on prolactin and thyreotropin serum concentrations in comparison with DA when used in equivalent dosages.