Biomedical subjects

Mark C Bellamy

Publications and source records attributed to Mark C Bellamy.

5 recordsLinked to original sources

PubMed2005

Management of polytraumatized patients with associated blunt chest trauma: a comparison of two European countries.

BACKGROUND: Blunt chest trauma represents one of the most common injuries in polytrauma patients. Blunt chest injury complicating polytrauma is associated with significant prolongation of intensive care stay. Further, it has a great impact on the timing of fixation of skeletal injuries, possibly contributing to adverse outcome. The purpose of this study is to assess whether there are any differences in the management and outcome of polytrauma patients with blunt chest trauma between trauma units in two different countries. Detailed information about advantages and disadvantages of these two systems might allow optimising the management of blunt chest trauma. PATIENTS AND METHODS: This investigation was performed using the polytrauma database of the German Trauma Society and the British Trauma Audit Research Network. After the definition of the inclusion abbreviated injury scale (AIS(chest) > or = 3) and injury severity score (ISS > 16) and exclusion (AIS(head/neck) > or = 2, referral from outside institutions) criteria, patients were recruited solely from these databases. RESULTS: 188 patients from the German database and 181 patients from the British database were enrolled in this study. Demographic data and injury pattern of the two patient populations did not significantly differ. The volume of initial red blood cell transfusion and length of the intensive care stay were significantly higher in Germany (p < 0.05). Mortality in the UK was 9% higher than in Germany (p = 0.057). Time to death in non-survivors was also significantly longer in Germany (p < 0.05). CONCLUSIONS: The reasons for the differences regarding survival times and survival rates seem to be multiple. German patients received more red blood cells, had a longer hospital stay in intensive care and a better survival rate. The use of kinetic therapy in Germany, not standard in the UK, may contribute to a more favourable outcome.

Abbreviated Injury Scale↗

PubMed2005

The safety and efficacy of the administration of recombinant activated factor VII in major surgery and trauma patients.

Recombinant activated Factor VII (rFVIIa) has been successfully used in the treatment of haemophilia A and B with associated inhibitors for some years. Activated Factor VII binds to activated platelets independently of tissue factor. The resulting stimulation of an exaggerated early thrombin burst at sites of vascular injury makes it an attractive potential treatment for massive, uncontrolled bleeding associated with surgery and trauma. This article describes the evidence relating to surgery and trauma. The lack of large, controlled trials of rFVIIa means that a definitive recommendation regarding its use cannot be made at present. However, in the context of clearly defined protocols and balanced treatment strategies, rFVIIa may have a role in traumatic bleeding. Large scale, randomised controlled trials in trauma are required, as is further work on the safety profile of rFVIIa with an independent international safety monitoring committee.

Drug Costs↗

PubMed2005

The safety and efficacy of the use of vasopressin in sepsis and septic shock.

Sepsis remains a significant problem and cause of morbidity and mortality in intensive care. Vasopressin infusions are currently used as rescue therapy for the treatment of vasodilatory, catecholamine-resistant septic shock. At present, there are no large randomised, controlled trials in the literature investigating vasopressin in this role, although two such studies are currently ongoing in Canada. This review outlines the pathophysiology of sepsis and that of vasopressin in sepsis and reviews the available evidence for the use of vasopressin in sepsis and septic shock. A review of the safety data for vasopressin in this indication is included. Recommendations for the use of vasopressin in septic shock, along with suggestions for the direction of further work in the field are presented.

Clinical Trials as Topic↗

PubMed2004

Complement membrane attack complex and hemodynamic changes during human orthotopic liver transplantation.

Hemodynamic changes and elevation of intracellular calcium following reperfusion in human liver transplantation occur rapidly and do not match the time course of cytokine expression, therefore, we postulate involvement of other, pre-formed substances, such as complement. We studied 40 adult patients undergoing liver transplantation. Blood was drawn for estimation of C3, C4, C3 degradation product, membrane attack complex, and CH100 levels and elastase (a marker of neutrophil activation) at induction of anesthesia, 5 minutes before reperfusion, 5 minutes and 60 minutes after reperfusion. Cardiac output was measured by thermodilution and systemic vascular resistance was calculated at these same time points. There was a significant rise in C5b-9 membrane attack complex (P =.0012) with a corresponding fall in C3 (P =.0013) and C4 (P =.0002) levels and a rise in C3 degradation product levels (P =.0006). There was no significant change in CH100. These changes very closely followed the hemodynamic changes of a significant fall in systemic vascular resistance index (P =.0024) and increase in cardiac index (P =.0005). Elastase rose from 356 +/- 53 to 557 +/- 40 microg/L (P <.0001). There is complement activation and neutrophil activation at reperfusion in liver transplantation. Dilution alone cannot explain the fall in C3 and C4 levels as there is a corresponding increase in membrane attack complex and C3 degradation product levels with time. As both C3 and C4 are consumed, the classical pathway must be active, though alternative and lectin activated pathways may also be involved. These findings may, at least in part, explain the hemodynamic changes typically seen at reperfusion in liver transplantation.

Adult↗

PubMed2002

The effect of methylene blue on the hemodynamic changes during ischemia reperfusion injury in orthotopic liver transplantation.

UNLABELLED: After graft reperfusion in orthotopic liver transplantation (OLT), ischemia reperfusion syndrome (IRS) is characterized by persistent hypotension with a low systemic vascular resistance. Methylene blue (MB) has been used as a vasopressor in sepsis and acute liver failure. We investigated the effect of MB on IRS during OLT. Thirty-six patients undergoing elective OLT were randomized to receive either a bolus of MB 1.5 mg/kg before graft reperfusion, or normal saline (placebo). We recorded hemodynamic variables, postoperative liver function tests, and time to hospital discharge. Blood samples were analyzed for arterial lactate concentration, cyclic 3',5'-monophosphate, and plasma nitrite/nitrate concentrations. The MB group had higher mean arterial pressure (P = 0.035), higher cardiac index (P = 0.04), and less epinephrine requirement (P = 0.02). There was no difference in systemic vascular resistance or central venous pressure. Serum lactate levels were lower at 1 h after reperfusion in MB patients, suggesting better tissue perfusion (P = 0.03). In the presence of MB, there was a reduction in cyclic 3',5'-monophosphate (P < 0.001), but not plasma nitrites. Postoperative liver function tests and time to hospital discharge were the same in both groups. MB attenuated the hemodynamic changes of IRS in OLT acting via guanylate cyclase inhibition. IMPLICATIONS: Methylene blue attenuates the hemodynamic changes of the ischemia reperfusion syndrome in liver transplantation, and this effect involves guanylate cyclase inhibition.

Blood Pressure↗