The effect of dopexamine on regional tissue oxygenation, systemic inflammation and amino acid exchange in major abdominal surgery

Is dopexamine superior to dopamine in the treatment of multiple trauma patients--a prospective, double-blind, randomised study

BACKGROUND

The goal of this prospective, randomised, double-blind clinical trial study was to assess the effects of dopexamine hydrochloride on organ failure, inflammatory mediators and splanchnic oxygenation in blunt multiple trauma patients at high risk of multiple organ dysfunction syndrome (MODS).

METHODS

We performed a prospective randomised controlled trial on 30 consecutive blunt multiple trauma patients with ISS>or=16, age 18-60 years and initial blood pressure >or=120 mmHg initially admitted to our level I trauma centre. Patients were randomised to treatment with dopamine (n=15) or dopexamine (n=15) for 48 h after admission. Outcome in terms of mortality, MODS, splanchnic perfusion, complications, duration of stay was statistically analysed.

RESULTS

Dopexamine treatment was associated with impaired organ function and an increased duration of ventilation and ICU stay compared with patients who received dopamine treatment. The acute inflammatory response was increased in the Dopexamine group while a decreased pHi and MEGX formation and increased serum lactate levels were measured.

CONCLUSIONS

The indication to use dopexamine hydrochloride appears questionable. In the absence of an antiinflammatory effect, dopexamine demonstrated a disadvantageous ICU course in regards to the organ function and the duration of treatment. In addition, a decreased pHi and MEGX formation suggested a deterioration of splanchnic oxygenation.

Splanchnic blood flow and oxygen consumption: effects of enteral nutrition and dopexamine in the elderly cardiac surgery patient

BACKGROUND

After cardiac surgery, patients are at risk of organ dysfunction because of decreased perfusion. Different measures have been used to increase the splanchnic blood flow. We compared the effects of enteral nutrition and dopexamine on the cardiac output, splanchnic blood flow and oxygen consumption.

METHODS

Sixteen patients undergoing cardiac surgery were included. Indocyanine green extraction and thermodilution were used for repeated measurements of the splanchnic blood flow and cardiac output. On the first post-operative day, indocyanine green infusion was started. Patients were randomized to start with dopexamine (Dpx group) or enteral nutrition (EN group). After 180 min, both groups received a combination of dopexamine and enteral nutrition. Blood gases from the hepatic vein and pulmonary and radial arteries were analysed repeatedly.

RESULTS

In the Dpx group, the cardiac index increased with dopexamine infusion, but not when enteral nutrition was added. In the EN group, enteral nutrition alone did not increase the cardiac index, but dopexamine addition increased the cardiac index in this group. The splanchnic blood flow increased initially in the Dpx group, but then returned to baseline and remained constant on addition of enteral nutrition. In the EN group, the splanchnic blood flow initially remained at baseline, but increased after dopexamine addition. There was no difference between the groups with regard to systemic or splanchnic oxygen consumption or the oxygen extraction ratio. In the Dpx group, lactate increased from baseline with no further increase on addition of enteral nutrition. Lactate was unchanged in the EN group.

CONCLUSIONS

Dopexamine and enteral nutrition caused no adverse effects on oxygen consumption or the oxygen extraction ratio. Enteral nutrition did not increase the splanchnic blood flow or cardiac index. Dopexamine increased the systemic blood flow with only a transient effect on the splanchnic blood flow. Dopexamine increased the lactate concentration, possibly indicating a more ischaemic condition.

Dopexamine and its role in the protection of hepatosplanchnic and renal perfusion in high-risk surgical and critically ill patients

BACKGROUND

Dopexamine is increasingly being used in high-risk surgical and critically ill patients to preserve hepatosplanchnic and renal perfusion. This systematic review of randomized controlled trials was undertaken to investigate the clinical evidence for using dopexamine in this role.

METHODS

Data sources included Medline, Cochrane Library, EMBASE and CINAHL and reference lists of relevant articles. Randomized controlled trials which compared dopexamine treatment with a control group, in high-risk surgical and critically ill adult patients and with primary outcome measures designed to assess hepatosplanchnic and renal perfusion were included. Articles not published in English were excluded.

RESULTS

Twenty-one trials were selected from the literature search. The results suggest that dopexamine may protect against colonic mucosal damage in patients undergoing abdominal aortic surgery and may improve gastric mucosal pHi in general surgical patients, especially those with preoperative gastric mucosal pHi measurements <7.35 and those undergoing pancreatico-duodenectomy surgery. Dopexamine may have beneficial effects on renal perfusion in patients undergoing cardiac surgery but appears to have little or no benefit on gastric mucosal pHi in the same patient population. In critically ill patients none of the studies demonstrated a beneficial effect of dopexamine on either hepatosplanchnic or renal perfusion.

CONCLUSION

The evidence provided by the existing studies is both inadequate and inconsistent. There is insufficient evidence to offer reliable recommendations on the clinical use of dopexamine for the protection of either hepatosplanchnic or renal perfusion in high-risk surgical patients. Furthermore, there is no current evidence to support a role for dopexamine in protecting either hepatosplanchnic or renal perfusion in critically ill patients.

Haemodynamic effects of dopexamine on postprandial splanchnic hyperaemia

BACKGROUND

The synthetic beta(2)-adrenergic and dopaminergic agonist dopexamine is supposed to prevent splanchnic hypoperfusion in critically ill patients, thus potentially interacting with haemodynamic effects of early enteral nutrition. However, precise mechanism of action and interaction with postprandial splanchnic hyperaemia of the drug are largely unknown, even in healthy subjects.

MATERIALS AND METHODS

Twelve healthy volunteers received dopexamine 1 microg x kg(-1) min(-1) and dopexamine and placebo (NaCl 0.9%) 3 microg x kg(-1) min(-1) in a randomized, double-blinded order (crossover-design). Splanchnic (Doppler ultrasound) and systemic (noninvasive cardiac monitoring) haemodynamic parameters were assessed at baseline and during infusion (fasted as well as 15, 30, 45 and 60 min after a standard liquid meal).

RESULTS

In fasted humans, dopexamine enhanced time-averaged maximum velocity (TAMX) in the superior mesenteric artery (1 microg + 40%; 3 microg + 82%, P < 0.05), portal vein (+ 63%; + 121%, P < 0.05) and femoral artery (+ 66%; + 87%, P < 0.05), in proportion to the increase of cardiac index (+ 33%; + 77%, both P < 0.05). In the postprandial state, TAMX rose significantly in the superior mesenteric artery (+ 139%) and portal vein (+ 68%) in the placebo group, showing the same absolute extent as dopexamine. The physiological postprandial buffer response of hepatic artery was conserved under all conditions.

CONCLUSIONS

Continuous infusion of dopexamine enhances mesenterial and portal perfusion in a dose-dependent manner without affecting the extent of physiological postprandial hyperaemia. Thus, dopexamine and enteral nutrition may interact with splanchnic haemodynamics by different pathways.

Anaesthetic management of a patient with microvillus inclusion disease for intestinal transplantation

We report the anaesthetic management of a 3-year-old-child with microvillus inclusion disease undergoing isolated small bowel transplantation. He required long-term total parenteral nutrition which was complicated with numerous episodes of catheter related sepsis. This resulted in thrombosis of the major blood vessels which critically restricted vascular access available for intravenous nutrition, becoming a life-threatening condition for the patient. Haemodynamic, respiratory parameters and urinary output were well preserved throughout the procedure. Besides a transitory increase in potassium following graft revascularization, biochemical changes were small. Anaesthetic management included comprehensive preoperative assessment, central venous angiography to depict accessibility of central and peripheral veins, assurance of additional vascular access through the intraoperative catheterization of the left renal vein, perioperative epidural analgesia and preservation of splanchnic perfusion to ensure implant viability.