Effects of altitude changes on mild-to-moderate closed-head injury in rats following acute high-altitude exposure

Novel energy optimizer, meldonium, rapidly restores acute hypobaric hypoxia-induced brain injury by targeting phosphoglycerate kinase 1

BACKGROUND

Acute hypobaric hypoxia-induced brain injury has been a challenge in the health management of mountaineers; therefore, new neuroprotective agents are urgently required. Meldonium, a well-known cardioprotective drug, has been reported to have neuroprotective effects. However, the relevant mechanisms have not been elucidated. We hypothesized that meldonium may play a potentially novel role in hypobaric hypoxia cerebral injury.

METHODS

We initially evaluated the neuroprotection efficacy of meldonium against acute hypoxia in mice and primary hippocampal neurons. The potential molecular targets of meldonium were screened using drug-target binding Huprot™ microarray chip and mass spectrometry analyses after which they were validated with surface plasmon resonance (SPR), molecular docking, and pull-down assay. The functional effects of such binding were explored through gene knockdown and overexpression.

RESULTS

The study clearly shows that pretreatment with meldonium rapidly attenuates neuronal pathological damage, cerebral blood flow changes, and mitochondrial damage and its cascade response to oxidative stress injury, thereby improving survival rates in mice brain and primary hippocampal neurons, revealing the remarkable pharmacological efficacy of meldonium in acute high-altitude brain injury. On the one hand, we confirmed that meldonium directly interacts with phosphoglycerate kinase 1 (PGK1) to promote its activity, which improved glycolysis and pyruvate metabolism to promote ATP production. On the other hand, meldonium also ameliorates mitochondrial damage by PGK1 translocating to mitochondria under acute hypoxia to regulate the activity of TNF receptor-associated protein 1 (TRAP1) molecular chaperones.

CONCLUSION

These results further explain the mechanism of meldonium as an energy optimizer and provide a strategy for preventing acute hypobaric hypoxia brain injury at high altitudes.

Anesthesia strategies for elderly patients with craniocerebral injury due to foreign-body penetration in the plateau region: a case report

Background

The administration of anesthesia for elderly individuals who are critically ill, suffering from severe craniocerebral injuries, and living in plateau regions presents a rare, intricate, and high-risk challenge. This case study outlines the specific anesthesia management protocols necessary for plateau-dwelling patients with significant craniocerebral damage undergoing prolonged invasive procedures.

Case report

A 76-year-old male patient had a 26-year history of foreign-body penetration of the skull and had experienced local purulent discharge and pain for the previous 20 days. The diagnoses included right hypoplasia, a foreign body in the skull with an infection, hypokalemia, hypoproteinemia, pulmonary fibrous foci, and bilateral pleural effusion. For almost 6 months, the patient suffered from recurring headaches, blurred vision, and sluggish bodily movement. The patient had a poor diet, poor sleep quality, normal urination, and no noticeable weight loss since the onset of the illness. The right anterior ear had a 2 cm skin abscess with yellow pus and a black metal foreign body tip. The left eyelid was red and swollen, and the left conjunctiva was hyperemic; the right eyelid showed no abnormalities, and both pupils were wide and round, with light and adjustment reflexes and no cyanosis on the lips. Skull development was normal. No dry or moist rales were audible in either lung. The heart rhythm was regular, and the heart rate was 50 bpm. Chest CT revealed left lung calcification foci, bilateral pleural effusion, and fiber foci in the lower lobes of both lungs.

Conclusion

Furthermore, the patient in question was of advanced age and had a complex medical history, including prolonged exposure to high altitudes and previous instances of severe craniocerebral trauma, among other uncommon pathophysiological characteristics. In particular, the patient also underwent surgical interventions at both high and low altitudes, adding to the complexity of their case. To ensure patient safety, close multidisciplinary collaboration, the development of a precise surgical plan, and the implementation of a suitable perioperative anesthetic management strategy are imperative.

Analysis on alteration of road traffic casualties in western China from multi-department data in recent decade

Background

Road traffic safety has considerably improved in China. However, the changes may differ in the economically backward and altitude higher western region. This study aims to investigate changes in the occurrence and severity of traffic casualties in western China and illuminate several key causal factors.

Materials and methods

Traffic accident data from the Annual Traffic Accident Statistics Report combined with population and vehicle data from the China Statistics Bureau between 2009 and 2019, were retrospectively analyzed. Traffic accident numbers, fatalities, human injury (HI), case fatality rates (CFR), mortality per 100,000 population (MRP), and mortality per 10,000 vehicles (MRV) were compared between the western and eastern regions. The HI, CFR, MRV, and MRP between the four groups based on the altitude of cities, below 500 meters, 500 to 1,500 meters, 1,500 to 3,000 meters, and over 3,000 meters, were compared using one-way analysis of variance. One hundred and seventy-eight cases of extremely serious traffic accidents were further analyzed in terms of accident occurrence time, vehicle type, road grade, road shape, accident pattern, and accident reason. The differences of accident characteristics between the eastern and western regions were compared using the chi-square test.

Results

The number of traffic accidents and fatalities decreased in low-altitude areas in western China. However, there was a significant increasing trend in the high altitude area. The HI, CFR, MRV, and MRP were higher in the western region than that in the eastern and national. Those accident indicators tended to increase with increasing altitude. And there were statistically significant differences (p < 0.05) among groups from different altitudes. Chi-square test results show that there are statistically significant differences (p < 0.05) in term of road grade, road shape, accident pattern between eastern and western. Low-grade roads, combined curved and sloping roads, and rollover were significant features associated with traffic accidents in the western region. Bad roads were the main cause of rollover accidents in western China, which will lead to more serious casualties. Over speeding, overloading, bad weather, vehicle failure, and driver error were the top five accident causes.

Conclusion

Traffic accidents are increasing in high-altitude areas of western China, and they lead to more severe casualties. The characteristics of serious traffic accidents in this part of the country differ from those of the eastern regions. Improving road safety facilities, restrictions of speed, and improving medical treatment at accident scenes may be effective measures to reduce traffic accidents related injuries in the western region.

Hemostatic Effects of Bio-Zeolite Gauze and QuikClot Combat Gauze on Major Bleeding in Rabbits Acutely Exposed to High Altitude

Objective: Hemostatic gauze application is an effective way to control major bleeding, which is the most common cause of death in trauma in both civilian and military settings. Coagulation derangement after acute exposure to high altitude might alter the effects of hemostatic gauzes. The present study aimed to observe the hemostatic effects of bio-zeolite gauze (BZG) and QuikClot Combat Gauze® (QCG) on major bleeding in rabbits acutely exposed to high altitude.Methods: Sixty rabbits were randomly and evenly divided into six groups. Animal models of simulated blast- and fragment-induced inguinal major bleeding were prepared in lower altitude and high-altitude areas, and BZG, QCG, and ordinary gauze without hemostatic material were used to control bleeding. The primary outcomes included immediate hemostasis rate, blood loss, and survival rate, while the secondary outcomes included hemodynamic parameters, laboratory examinations, and coagulation-relevant markers.Results: The overall effects of BZG and QCG were better than those of ordinary gauze, with a higher immediate hemostatic rate, less blood loss, and higher survival rate at 90 min after gauze application and higher red blood cell and platelet counts and lower creatinine level at 30 min after gauze application in lower altitude. The concentrations of coagulation factor XII and factor X in rabbits acutely exposed to high altitude were significantly lower than those in lower altitude. At high altitude, the hemostatic effects of BZG did not decrease significantly compared to those in the lower altitude, whereas those of ordinary gauze and QCG decreased significantly at high altitude compared to those in the lower altitude.Conclusions: Coagulation derangement after acute exposure to high altitude has negative effects on ordinary gauze and QCG but has no significant negative hemostatic effects on BZG.

The Clinical Differences of Patients With Traumatic Brain Injury in Plateau and Plain Areas

Objective

Traumatic brain injury (TBI) is a leading cause of death and disability, which tends to have a worse clinical recovery if it occurs in plateau areas than in plain areas. To explore the underlying cause of this outcome preliminarily, this retrospective study was conducted to compare the clinical differences of patients with TBI in plateau and plain areas.

Methods

In this study, 32 patients with TBI in plateau areas (altitude ≥ 4,000 m) and 32 in plain areas (altitude ≤ 1,000 m) were recruited according to the inclusion and exclusion criteria from June 2020 to December 2021. The collected data and compared parameters include clinical features, head CT presentations and Marshall classifications, hematology profile, lipid profile, coagulation profile, and multiorgan (cardiac, liver, renal) function within 24 h of hospital admission, as well as the treatment method and final outcome.

Results

There were no obvious differences in demographic characteristics, including gender, age, height, and weight, between patients with TBI in plateau and plain areas (all P > 0.05). Compared to patients with TBI in plain areas, the time before hospital admission was longer, heartbeat was slower, systolic blood pressure (SBP) was lower, and hospital stays were longer in patients with TBI in plateau areas (all P < 0.05). More importantly, elevated red blood cells (RBCs) count and hemoglobin (HGB) level, enhanced coagulation function, and higher rates of multiorgan (cardiac, liver, and renal) injury were found in patients with TBI in plateau areas (all P < 0.05).

Conclusion

Patients with TBI in plateau areas presented with altered clinical characteristics, enhanced coagulation function, and aggravated predisposition toward multiorgan (cardiac, liver, and renal) injury, compared to patients with TBI in plain areas. Future prospective studies are needed to further elucidate the influences of high altitude on the disease course of TBI.