The coronary vascular response to the metaboreflex at low altitude and during acute and prolonged high altitude in males.

Myocardial oxygen delivery is primarily regulated through changes in vascular tone to match increased metabolic demands. In males, activation of the muscle metaboreflex during acute isocapnic hypoxia results in paradoxical coronary vasoconstriction. Whether coronary blood velocity is reduced by metaboreflex activation following travel and/or adaptation to high altitude is unknown. This study determined if the response of the coronary vasculature to muscle metaboreflex activation at low altitude differs from acute (1/2 days) and prolonged (8/9 days) high altitude. Healthy males (n = 16) were recruited and performed isometric handgrip exercise (30% max) followed by postexercise circulatory occlusion (PECO) to isolate the muscle metaboreflex at low altitude and following acute and prolonged high altitude (3,800 m). Mean left anterior descending coronary artery blood velocity (LADvmean, transthoracic Doppler echocardiography), heart rate, mean arterial pressure (MAP), ventilation, and respired gases were assessed during baseline and PECO at all time points. Coronary vascular conductance index (CVCi) was calculated as LADVmean/MAP. The change in LADvmean (acute altitude: -1.7 ± 3.9 cm/s, low altitude: 2.6 ± 3.4 cm/s, P = 0.01) and CVCi (acute altitude: -0.05 ± 0.04 cm/s/mmHg, low altitude: -0.01 ± 0.03 cm/s/mmHg, P = 0.005) induced by PECO differed significantly between acute high altitude and low altitude. The change in LADVmean and CVCi induced by PECO following prolonged high altitude was not different from low altitude. Our results suggest that coronary vasoconstriction with metaboreflex activation in males is greatest following acute ascent to high-altitude and restored to low-altitude levels following 8-9 days of acclimatization.NEW & NOTEWORTHY Coronary blood flow is regulated by both local metabolic signaling pathways and adrenergic activity in healthy humans. The integrated effects of these systems on coronary vascular physiology are not well understood. Using Doppler echocardiography, this study demonstrates that adrenergic stimulation caused by metaboreflex activation leads to greater reductions in coronary vascular conductance following acute high-altitude but not after prolonged high-altitude exposure.

Injury patterns of patients presenting to a non-governmental hospital in Western Uganda.

INTRODUCTION: Injury is a leading cause of morbidity and mortality globally and disproportionately affects low-income countries. While most injury data comes from tertiary care centers in urban settings, the purpose of this study was to describe the characteristics and severity of injury in rural Uganda and the associated treatment patterns and delays in care. METHODS: This is a retrospective cohort study of a trauma registry that was implemented at Masindi-Kitara Medical Center (MKMC), a rural hospital in Western Uganda. Demographic information, injury characteristics, modified Kampala Trauma Scores (M-KTS), and treatment modalities over a 12 month period were retrospectively collected from paper-based registry forms completed for all injury patients presenting to MKMC. RESULTS: A total of 350 patients were entered into the trauma registry. Most patients were male (71.2%) with a median age of 26.5 years. Motorcycle crashes were the most prevalent mechanism of injury (42.3%) with the majority being unhelmeted (83.3%). Soft tissue injury was the most common diagnosis (44.9%). Patients were frequently treated in the outpatient department and then discharged (54.8%). Patients requiring admission or transfer (M-KTS = 11.57 or 11.67) tended to have a lower M-KTS than discharged patients (M-KTS = 12.75). Analgesics (74.6%) and antibiotics (52.9%) were the most common treatments administered. For those patients requiring admission (29.4%), only one in-hospital death was documented. Thirty-nine percent of patients reported a delay in seeking care, most frequently due to lack of transportation (31.5%) with a median time of delay of 11 h. CONCLUSION: Road traffic injuries were the leading cause of injury in Masindi, with a high proportion of injuries associated with unhelmeted motorcycle crashes. Future opportunities to prevent injury and improve care may be seen through improved prehospital care, enforcement of helmet laws, increased access to neurosurgical services, and enactment of hospital quality improvement measures.

Injury patterns of patients presenting to a non-governmental hospital in Western Uganda

Introduction: Injury is a leading cause of morbidity and mortality globally and disproportionately affects low-income countries. While most injury data comes from tertiary care centers in urban settings, the purpose of this study was to describe the characteristics and severity of injury in rural Uganda and the associated treatment patterns and delays in care. Methods: This is a retrospective cohort study of a trauma registry that was implemented at Masindi-Kitara Medical Center (MKMC), a rural hospital in Western Uganda. Demographic information, injury characteristics, modified Kampala Trauma Scores (M-KTS), and treatment modalities over a 12 month period were retrospectively collected from paper-based registry forms completed for all injury patients presenting to MKMC. Results: A total of 350 patients were entered into the trauma registry. Most patients were male (71.2%) with a median age of 26.5 years. Motorcycle crashes were the most prevalent mechanism of injury (42.3%) with the majority being unhelmeted (83.3%). Soft tissue injury was the most common diagnosis (44.9%). Patients were frequently treated in the outpatient department and then discharged (54.8%). Patients requiring admission or transfer (M-KTS = 11.57 or 11.67) tended to have a lower M-KTS than discharged patients (M-KTS = 12.75). Analgesics (74.6%) and antibiotics (52.9%) were the most common treatments administered. For those patients requiring admission (29.4%), only one in-hospital death was documented. Thirty-nine percent of patients reported a delay in seeking care, most frequently due to lack of transportation (31.5%) with a median time of delay of 11 h. Conclusion: Road traffic injuries were the leading cause of injury in Masindi, with a high proportion of injuries associated with unhelmeted motorcycle crashes. Future opportunities to prevent injury and improve care may be seen through improved prehospital care, enforcement of helmet laws, increased access to neurosurgical services, and enactment of hospital quality improvement measures