Trauma care in the tropics: addressing gaps in treating injury in rural and remote Australia.

In Australia, over half a million people are admitted to hospital every year as a result of injury, and where you live matters. Rural populations have disproportionately higher injury hospitalisation rates (1.5-2.5-fold), higher rates of preventable secondary complications, higher mortality rates (up to fivefold), and higher costs (threefold) than patients injured in major cities. These disparities scale up rapidly with increased remoteness, and shift the service needle from 'scoop and run' to 'continuum of care'. Poorer outcomes, however, are not solely due to longer retrieval distances or delays; they arise from inefficiencies in one or more potentially modifiable factors in the chain of survival. After discussing the burden of injury in Australia, we present a brief history of retrieval services in Queensland and discuss how remoteness requires a different kind of service delivery with many moving parts from point of injury to definitive care. We next address the ongoing challenges for the Australian Trauma Registry, and how centralisation of data from the metropolitan cities masks the inequities in rural and remote trauma. There is an urgent need for accurate data from all service providers around Australia to inform state and federal governments, and we highlight the paucity of trauma data analysis in North Queensland. Last, we identify some major gaps in treating rural and remote polytrauma and en-route patient stabilisation, and discuss the relevance of combat casualty care research and practices. We conclude that a greater emphasis should be placed on collecting more robust trauma patient records, as only accurate data will drive change.

Short-term outcome of adenosine-lidocaine-magnesium polarizing cardioplegia in humans.

OBJECTIVES: Hyperkalaemic depolarized myocardial arrest is the cornerstone of myocardial protection, although some potassium-related cytotoxicity has been demonstrated. Polarized arrest has gained interest because of a reported better myocardial protection in preclinical studies. The goal of this study was to analyse the quality of myocardial protection and hospital outcome after normokalaemic adenosine-lidocaine-magnesium (ALM) blood polarizing cardioplegia, compared to hyperkalaemic blood Buckberg depolarizing cardioplegia, in elective routine adult cardiac surgery. METHODS: One thousand consecutive elective adult cardiac patients [627 undergoing ALM-polarizing cardioplegia (ALM-POL) vs 373 Buckberg depolarized cardioplegia (BUCK-DEPOL)] who were operated on were analysed. Perioperative leakage of high-sensitivity troponin I (Hs-TnI), peripheral lactate, inotropic and vasoactive daily requirement [maximal vasoactive inotropic score (VISMAX)], hospital mortality and morbidity were collected and compared in the overall population and in the propensity score (PS) matched population (206 pairs). RESULTS: A significantly lower leakage of Hs-TnI during hospitalization was detected in patients receiving ALM-POL versus those receiving BUCK-DEPOL (group time P < 0.001 for overall population and PS matched pairs). The maximum value of postoperative Hs-TnI was also lower after ALM-POL (P < 0.001 in both cohorts), and spontaneous recovery of sinus rhythm at aortic declamping was higher (P < 0.001 in favour of ALM-POL). Maximal VISMAX during hospitalization was significantly higher after BUCK-DEPOL in both cohorts (P = 0.019 for overall population; P = 0.031 for PS matched population), with significantly higher VISMAX on the day of surgery in BUCK-DEPOL PS matched patients (P = 0.042). No other significant differences in hospital morbidity and mortality were found. CONCLUSIONS: Despite comparable short-term clinical outcomes, ALM-POL cardioplegia proved superior in terms of quality of myocardial protection compared to BUCK-DEPOL cardioplegia in elective routine adult cardiac surgery.

Cardioplegia between Evolution and Revolution: From Depolarized to Polarized Cardiac Arrest in Adult Cardiac Surgery.

Despite current advances in perioperative care, intraoperative myocardial protection during cardiac surgery has not kept the same pace. High potassium cardioplegic solutions were introduced in the 1950s, and in the early 1960s they were soon recognized as harmful. Since that time, surgeons have minimized many of the adverse effects by lowering the temperature of the heart, lowering K+ concentration, reducing contact K+ time, changing the vehicle from a crystalloid solution to whole-blood, adding many pharmacological protectants and modifying reperfusion conditions. Despite these attempts, high potassium remains a suboptimalway to arrest the heart. We briefly review the historical advances and failures of finding alternatives to high potassium, the drawbacks of a prolonged depolarized membrane, altered Ca2+ intracellular circuits and heterogeneity in atrial-ventricular K+ repolarization during reanimation. Many of these untoward effects may be alleviated by a polarized membrane, and we will discuss the basic science and clinical experience from a number of institutions trialling different alternatives, and our institution with a non-depolarizing adenosine, lidocaine and magnesium (ALM) cardioplegia. The future of polarized arrest is an exciting one and may play an important role in treating the next generation of patients who are older, and sicker with multiple comorbidities and require more complex operations with prolonged cross-clamping times.

Adenosine, lidocaine, and Mg2+ fluid therapy leads to 72-hour survival after hemorrhagic shock: A model for studying differential gene expression and extending biological time.

BACKGROUND: Noncompressible torso hemorrhage is a leading cause of traumatic death. Our aim was to examine survival time and the expression of key master genes of cellular metabolism after 3% NaCl adenosine, lidocaine, and Mg (ALM) bolus and 4 hours 0.9% NaCl/ALM "drip" in a rat model of uncontrolled hemorrhagic shock. METHODS: Male Sprague-Dawley rats (425 ± 8 g) were anesthetized and randomly assigned to saline controls (n = 10) or ALM therapy (n = 10). Hemorrhage was induced by liver resection (60% left lateral lobe). After 15 minutes, a single intravenous bolus of 3% NaCl ± ALM (0.7 mL/kg) was administered (Phase 1), and after 60 minutes, a 0.9% NaCl ± ALM stabilization "drip" (0.5 mL/kg per hour) was infused for 4 hours (Phase 2) with 72 hours monitoring. Mean arterial pressure and lactate were measured. After 72 hours (or high moribund score), tissues were freeze-clamped and stored at -80°C. Total RNA was extracted in heart, brain, and liver, and the relative expressions of amp-k, mtCO3, PGC-1α, and sirt-1 genes were determined. RESULTS: Kaplan-Meier survival curves showed that controls had a mean survival time of 22.6 ± 4.5 hours, and ALM animals, 72 ± 0 hours (p < 0.05). Death in controls was accompanied by approximately sevenfold increase in lactate, while ALM animals maintained lactates similar to baseline over 72 hours. The relative expression of amp-k, PGC-1α, and sirt-1 in heart and brain was 1.5-fold and 2.7-fold higher in the ALM group compared with controls (p < 0.05), with the exception of mitochondrial encoded cytochrome C oxidase III pseudogene 1 in heart, which was 19-fold higher. In contrast, amp-k, sirt-1, and mtCO3 gene expression in liver was significantly 29-41% lower in the ALM group compared with controls, and PGC-1α was 75% lower. CONCLUSION: Small-volume ALM therapy led to 3.3-times longer survival time compared with saline controls after hemorrhagic shock. A hallmark of the ALM-survival phenotype in heart and brain was an upregulation of amp-k, PGC-1α, sirt-1, and mtCO3 to presumably "boost" mitochondrial function and ATP production, and a contrasting downregulation in liver. These central-peripheral differences in gene expression require further investigation.

7.5% NaCl Resuscitation Leads to Abnormal Clot Fibrinolysis after Severe Hemorrhagic Shock and its Correction with 7.5% NaCl Adenosine, Lidocaine, and Mg2.

BACKGROUND: Hyperfibrinolysis is a common complication of hemorrhagic shock. Our aim was to examine the effect of small-volume 7.5% NaCl adenosine, lidocaine, and Mg2+ (ALM) on fibrinolysis in the rat model of hemorrhagic shock. METHODS: Rats were anesthetized and randomly assigned to one of four groups: (1) baseline, (2) shock, (3) 7.5% NaCl controls, and (4) 7.5% NaCl ALM. Animals were bled for 20 min (42% blood loss) and left in shock for 60 min before resuscitation with 0.3 ml intravenous bolus 7.5% NaCl ± ALM. Rats were sacrificed at 5, 10, 15, 30, and 60 min for rotation thromboelastometry and 15 and 60 min for ELISA analyses. RESULTS: After hemorrhagic shock, 7.5% NaCl failed to resuscitate and exacerbated coagulopathy and fibrinolysis. At 15 and 60 min, the activation as extrinsically-activated test using tissue factor (EXTEM) with aprotinin to inhibit fibrinolysis (APTEM) test showed little or no correction of fibrinolysis, indicating a plasmin-independent fibrinolysis. Clots also had ~ 60% lower fibrinogen (fibrin-based EXTEM activated test with platelet inhibitor cytochalasin D A10) and 36%-50% reduced fibrinogen-to-platelet ratio (11%-14% vs. 22% baseline). In contrast, 7.5% NaCl ALM resuscitated mean arterial pressure and attenuated hyperfibrinolysis and coagulopathy by 15 min. Correction was associated with lower plasma tissue factor, higher plasminogen activator inhibitor-1, and lower D-dimers (5% of controls at 60 min). Platelet selectin fell to undetectable levels in ALM animals, which may imply improved endothelial and platelet function during resuscitation. CONCLUSIONS: Small-volume 7.5% NaCl resuscitation exacerbated coagulopathy and fibrinolysis that was not corrected by APTEM test. Fibrinolysis appears to be associated with altered fibrin structure during early clot formation and elongation. In contrast, 7.5% NaCl ALM rapidly corrected both coagulopathy and hyperfibrinolysis.

Small-Volume Adenosine, Lidocaine, and Mg2+ 4-Hour Infusion Leads to 88% Survival after 6 Days of Experimental Sepsis in the Rat without Antibiotics.

Innovative host-directed drug therapies are urgently required to treat sepsis. We tested the effect of a small-volume 0.9% NaCl adenosine, lidocaine, and Mg2+ (ALM) bolus and a 4-h intravenous infusion on survivability in the rat model of polymicrobial sepsis over 6 days. ALM treatment led to a significant increase in survivability (88%) compared to that of controls (25%). Four controls died on day 2 to 3, and two died on day 5. Early death was associated with elevated plasma and lung inflammatory markers (interleukin-6 [IL-6], IL-1ß, C-reactive protein), reduced white blood cell (WBC) count, hypoxemia, hypercapnia, acidosis, hyperkalemia, and elevated lactate, whereas late death was associated with a massive cytokine storm, a neutrophil-dominated WBC rebound/overshoot, increased lung oxidant injury, edema, and persistent ischemia. On day 6, seven of eight ALM survivors had inflammatory and immunological profiles not significantly different from those of sham-treated animals. We conclude in the rat model of experimental sepsis that small-volume ALM treatment led to higher survivability at 6 days (88%) than that of controls (25%). Early death in controls (day 2 to 3) was associated with significantly elevated plasma levels of IL-1ß, IL-6, and C-reactive protein, severe plasma lymphocyte deficiency, reduced neutrophils, and acute lung injury. Late death (day 5) was associated with a massive neutrophil inflammatory storm, increased lung injury, and persistent ischemia. Possible mechanisms of ALM protection are discussed.

Adenosine, lidocaine, and Mg2+ (ALM): From cardiac surgery to combat casualty care--Teaching old drugs new tricks.

New frontline drugs and therapies are urgently required to protect the body from primary and secondary injuries. We review more than 10 years of work on adenosine, lidocaine, and magnesium (ALM) and its possible significance to civilian and military medicine. Adenosine is an endogenous nucleoside involved in nucleotide production, adenosine triphosphate turnover, and restoration of supply and demand imbalances. Lidocaine is a local anesthetic and Class 1B antiarrhythmic, and magnesium is essential for ionic regulation and cellular bioenergetics. Individually, each plays important roles in metabolism, immunomodulation, inflammation, and coagulation. The original idea to combine all three was as a "polarizing" cardioplegia, an idea borrowed from natural hibernators. Two recent prospective, randomized human trials have demonstrated its safety and superiority in myocardial protection over high-potassium "depolarizing" solutions. The next idea came from witnessing how the human heart spontaneously reanimated after complex operations with little inotropic support. At high doses, ALM arrests the heart, and at lower doses, it resuscitates the heart. In rat and pig models, we have shown that ALM intravenous bolus and infusion "drip" protects against acute regional myocardial ischemia, lethal arrhythmias, cardiac arrest, compressible and noncompressible blood loss and shock, endotoxemia, and sepsis. Individually, adenosine, lidocaine, or magnesium fails to protect. Protection is afforded in part by reducing inflammation, correcting coagulopathy, and lowering energy demand. We propose a unifying hypothesis involving improved central, cardiovascular and endothelium coupling to maintain sufficient tissue oxygenation and reduce primary and secondary "hit" complications. As with any new drug innovation, translation into humans is challenging.