Volume 3 Supplement 1
Dopexamine reduces the incidence of colonic ischaemia following aortic surgery: a randomized placebo controlled study
© Current Science Ltd 1999
Published: 16 March 2000
Mechanisms involved in the development of colonic ischaemia following aortic surgery are not fully understood and there are conflicting reports regarding predisposing factors. Dopexamine hydrochloride, a synthetic catecholamine with both dopaminergic and β2 agonist properties, has been demonstrated to have anti-inflammatory properties.
To evaluate the effect of dopexamine hydrochloride on the incidence of colonic ischaemia following aortic surgery
Thirty patients, mean age 65.1 years (range 46-84), undergoing elective infrarenal aortic surgery were randomized to receive a peri-operative infusion of either dopexamine at 2 μg/kg/min (n = 12) or 0.9% saline placebo (n = 18). All patients underwent colonoscopy and biopsy following induction of anaesthesia and at one week post-operatively. Sections were stained with haematoxylin and eosin, mast cell tryptase (MCT), myeloperoxidase (MPO) and both the inducible (iNOS) and endothelial (eNOS) isoforms of nitric oxide synthase. Sections were analysed blind and independently by two histopathologists. Patient and operative related data were collected and stored separately.
Colonic ischaemia was noted in 9 (30%) patients based on microscopic findings. Endoscopy alone had a sensitivity of 55.5%. There was a significantly lower incidence of colonic ischaemia in patients receiving dopexamine compared to placebo (P < 0.05). One death resulted from colonic infarction in the placebo group 11 days post-operatively. There was increased MPO and MCT expression in patients with histological evidence of ischaemia (P < 0.05). iNOS staining within the vascular (P = 0.001) and lamina propria (P < 0.05) components of the mucosa was also significantly greater. No association was found with eNOS.
Peri-operative dopexamine infusion confers a degree of protection to colonic mucosa following aortic surgery, possibly through an anti-inflammatory effect.