TnT: blowing the cover from perioperative myocardial injury

Immune-inflammatory activation after a single laparotomy in a rat model: effect of adenosine, lidocaine and Mg2+ infusion to dampen the stress response

Our aim was to examine the effect of low-volume 0.9% NaCl adenosine, lidocaine and Mg2+ (ALM) ‘drip’ on early immune-inflammatory activation after a single laparotomy with no further manipulation. Male Sprague–Dawley rats were anesthetized and randomly assigned to one of the groups, baseline, 1 h infusion 0.9% NaCl ± ALM and metrics, 1 h infusion and 6-h metrics, and 6 h continuous infusion and metrics. Complete blood count, acid–base balance, systemic levels of IL-6 and IL-10, and coagulation status were measured. After 1 h, there was a disproportionate increase in circulating neutrophils between saline and ALM groups despite an identical 45% fall in lymphocytes. Disproportionate increases also occurred in platelet counts 1 h after surgery, and saline controls had increased respiratory alkalosis at 6 h with higher lactate. Systemic inflammation was also evident after 1 h in both groups (plasma IL-6 increase) and was amplified in saline-controls after 6 h. The ALM group increased anti-inflammatory cytokine IL-10. Surgery was not associated with acute coagulopathy; however, there were significant reductions in fibrinolysis. Following a single laparotomy, ALM infusion appeared to reduce stress-induced release of neutrophils and platelets into the circulation, and reduced acid–base disturbance. After 1 h, both groups had similar IL-6 levels, but ALM animals had increased IL-10, indicating improved inflammatory balance. The uncoupling of inflammation and coagulation activation but not fibrinolysis may offer a unique opportunity to investigate differential activation of innate immunity in response to sterile injury in this model.

Isolated cardiac troponin rise does not modify the prognosis in elderly patients with hip fracture

Perioperative myocardial infarction remains a life-threatening complication in noncardiac surgery and even an isolated troponin rise (ITR) is associated with significant mortality. Our aim was to assess the prognostic value of ITR in elderly patients with hip fracture.In this cohort study, all patients admitted between 2009 and 2013 in our dedicated geriatric postoperative unit after hip fracture surgery with a cardiac troponin I determination were included and divided into Control, ITR, and acute coronary syndrome (ACS) groups. The primary end point was a composite criteria defined as 6-month mortality and/or re-hospitalization. Secondary end points included 30-day mortality, 6-month mortality, and 6-month functional outcome.Three hundred twelve patients were (age 85 ± 7 years) divided into Control (n = 217), ITR (n = 50), and ACS (n = 45) groups. There was no significant difference for any postoperative complications between ITR and Control groups. In contrast, atrial fibrillation, acute heart failure, hemorrhage, and ICU admission were significantly more frequent in the ACS group. Compared to the Control group, 6-month mortality and/or rehospitalization was not significantly modified in the ITR group (26% vs. 28%, P = 0.84, 95% confidence interval [CI] of the difference -13%-14%), whereas it was increased in the ACS group (44% vs. 28%, P = 0.02, 95% CI of the difference 2%-32%). ITR was not associated with a higher risk of new institutionalization or impaired walking ability at 6 months, in contrast to ACS group.In elderly patients with hip fracture, ITR was not associated with a significant increase in death and/or rehospitalization within 6 months.

Addressing the Global Burden of Trauma in Major Surgery

Despite a technically perfect procedure, surgical stress can determine the success or failure of an operation. Surgical trauma is often referred to as the "neglected step-child" of global health in terms of patient numbers, mortality, morbidity, and costs. A staggering 234 million major surgeries are performed every year, and depending upon country and institution, up to 4% of patients will die before leaving hospital, up to 15% will have serious post-operative morbidity, and 5-15% will be readmitted within 30 days. These percentages equate to around 1000 deaths and 4000 major complications every hour, and it has been estimated that 50% may be preventable. New frontline drugs are urgently required to make major surgery safer for the patient and more predictable for the surgeon. We review the basic physiology of the stress response from neuroendocrine to genomic systems, and discuss the paucity of clinical data supporting the use of statins, beta-adrenergic blockers and calcium-channel blockers. Since cardiac-related complications are the most common, particularly in the elderly, a key strategy would be to improve ventricular-arterial coupling to safeguard the endothelium and maintain tissue oxygenation. Reduced O2 supply is associated with glycocalyx shedding, decreased endothelial barrier function, fluid leakage, inflammation, and coagulopathy. A healthy endothelium may prevent these "secondary hit" complications, including possibly immunosuppression. Thus, the four pillars of whole body resynchronization during surgical trauma, and targets for new therapies, are: (1) the CNS, (2) the heart, (3) arterial supply and venous return functions, and (4) the endothelium. This is termed the Central-Cardio-Vascular-Endothelium (CCVE) coupling hypothesis. Since similar sterile injury cascades exist in critical illness, accidental trauma, hemorrhage, cardiac arrest, infection and burns, new drugs that improve CCVE coupling may find wide utility in civilian and military medicine.