The ultrasound-based cardiac output monitoring is a useful tool to define baseline hemodynamic parameters in healthy permanent residents at high altitude: results of a monocentric pilot study.

Previous studies on the cardiac data of healthy permanent residents living in high-altitude regions such as Tibet and the Andes have yielded inconsistent findings and significant disparities. These discrepancies can be mainly attributed to the invasive methods conventionally used for parameter evaluation. However, with the introduction of cutting-edge ultrasound technology, there is now an innovative approach to addressing and reconciling these variations. In this pilot study, we employed an ultrasound-based cardiac output monitoring (USCOM) device to evaluate cardiac output and related hemodynamic variables in a group of 20 healthy high-altitude Andean residents (comprising 10 men and 10 women) aged between 26 and 35 years old. The monocentric study was carried out in La Paz, Bolivia, located between at an altitude of 3,600-4,000 m. A total of 60 hemodynamic measurements were evaluated, accounting for three technical replicates per subject. Our results showed strong intrasubject reproducibility and revealed important differences related to both sex and hemodynamic parameters in highlanders compared to individuals residing at sea level. We conclude that USCOM represents a highly reliable technology for performing hemodynamic measurements in high-altitude residents. Our preliminary findings underscore the need for larger studies, encompassing larger sample sizes, specifically tailored to gender considerations, and extendable to broader highland populations. These findings have special significant implications for the management of hemodynamics in intensive care and postoperative settings, warranting further comprehensive research efforts.

Edema agudo de pulmón asociado al mal de altitud agudo en Huaraz: estudio transversal analítico / Acute high-altitude pulmonary edema in Huaraz: an analytical cross-sectional study

RESUMEN Objetivo: Describir algunas características epidemiológicas y clínicas del edema agudo de pulmón por mal de altitud (EAP) observadas en un hospital de Áncash (3052 m s. n. m.). Materiales y métodos: Estudio observacional descriptivo de 57 pacientes, quienes se presentaron en el Servicio de Emergencia del Hospital Víctor Ramos Guardia Huaraz entre enero de 1997 y enero del 2020. Todos cumplieron con los criterios diagnósticos de Lake Louise y una radiografía del tórax. La información se analizó mediante los usos de mediana y rango. Resultados: El 91,20 % de casos fueron del sexo masculino; 38,61% hicieron EAP de ascenso; 61,40 %, EAP de reascenso. El 21,10 % tuvo antecedente de EAP; 19,33 % desarrolló infección respiratoria previa; 10,53 %, un proceso patológico concomitante; 40,42 % hizo EAP durante el primer trimestre del año, y 45 % estuvo 10 días o menos a baja altitud. La presentación clínica incluyó disnea de reposo, crepitantes pulmonares, taquipnea, taquicardia y radiografía del tórax anormal en 100 % de los casos; tos productiva (96,52 %), dolor torácico (92,95 %), cefalea (56,11 %), cianosis (68,41 %), esputo rosado (42,13 %), fiebre (21,13 %) y leucocitosis (60,82 %). La mediana para la edad fue 20 años, frecuencia respiratoria 36/min, frecuencia cardiaca 124/min, PAS 100 mmHg, PAD 60 mmHg, temperatura 37,2 ºC, Hb 17,3 g/dl, Hto 53 %, recuento de leucocitos 12,500/mm3, resolución radiográfica del edema a las 48 horas. No hubo fallecidos. Conclusiones: Los factores que influyen en el EAP y sus determinantes son altura alcanzada, velocidad de ascenso, factores genéticos y antecedentes de EAP.

ABSTRACT Objective: To describe some epidemiological and clinical characteristics of acute high-altitude pulmonary edema (HAPE) observed in a hospital of the highlands of Ancash, located at 3,052 m a.s.l. Materials and methods: A descriptive observational study conducted with 57 patients who attended the emergency service of Hospital Víctor Ramos Guardia - Huaraz between January 1997 and January 2020. All patients fulfilled Lake Louise Criteria and had a chest X-ray. Median and range were used to analyze the information. Results: Male sex accounted for 91.20 %, ascent HAPE 38.61 % and re-ascent HAPE 61.40 %. Out of all patients, 21.10 % had a history of HAPE, 19.33 % developed a previous respiratory infection, 10.53 % had a concomitant disease, 40.42 % had HAPE during the first quarter of the year and 45 % had been 10 days or less at low altitude. Patients' clinical presentation included dyspnea at rest, pulmonary crackles, tachypnea, tachycardia and abnormal X-ray in 100 %; productive cough in 96.52 %; chest pain in 92.95 %; headache in 56.11 %; cyanosis in 68.41 %; pink sputum in 42.13 %; fever in 21.13 % and leukocytosis in 60.82 %. The median age was 20 years, respiratory rate 36/min, heart rate 124/min, SBP 100 mmHg, DBP 60 mmHg, temperature 37.2 °C, HGB 17.3 g/dl, HCT 53 %, WBC 12,500/mm3, radiographic resolution of the edema in 48 hours. There were no deaths. Conclusions: The factors that influence HAPE and its determinants are altitude, rate of ascent, genetic factors and history of HAPE.

Neumomediastino espontáneo de reentrada en la altitud: reporte de dos casos

Se describen dos casos de neumomediastino espontáneo (NME) en adolescentes varones, saludables y nativos de la altura cuando retornaron a sus hogares provenientes del nivel del mar. Ambos acudieron por el Servicio de Emergencia del hospital Víctor Ramos Guardia de Huaraz, Ancash (3052 m s. n. m.) en el mes de febrero del 2020. El primer caso es el de un joven de 16 años que retornó a su hogar (a 2964 m s. n. m.) luego de permanecer doce días a nivel del mar, en Lima. Seis horas después del regreso fue a trabajar a la chacra, se sintió cansado y empezó a toser, y luego empezó el dolor torácico, la disnea y el enfisema subcutáneo. El segundo caso corresponde a un varón de 17 años, que volvió a su hogar (3140 m s. n. m.) después de pasar dos semanas a nivel del mar (Barranca); doce horas después del retorno, va a trabajar a la chacra y presenta tos, disnea, dolor torácico, dolor de garganta y enfisema subcutáneo. Ambos jóvenes desarrollaron una hipoxemia. El neumomediastino espontáneo se diagnosticó con las radiografías de tórax. En el segundo paciente, el cuadro se asoció a un leve edema pulmonar de altura. Ninguno de los pacientes tenía antecedentes de traumatismos, uso de drogas ilícitas, comorbilidad o de enfermedades previas asociadas a la altura. El manejo de la enfermedad fue conservador, sintomático, de soporte y observación clínica. Cuando un paciente joven y saludable acude a la emergencia con dolor torácico, disnea y enfisema subcutáneo, el neumomediastino espontáneo se debe considerar como un posible diagnóstico y, de inmediato, solicitar radiografías torácicas, frontal y lateral, que abarquen la región cervical. El diagnóstico diferencial permite un manejo adecuado y preciso para los pacientes con neumomediastino espontáneo.

We describe two cases of spontaneous pneumomediastinum (SPM) that occurred in healthy, high-altitude native adolescent males when returning to their home from sea level. Both attended the Emergency Department of the Hospital Víctor Ramos Guardia in Huaraz, Ancash (3,052 m a.s.l.), in February 2020. Case 1 was a 16-year-old man who returned home (2,964 m a.s.l.) after twelve days at sea level (Lima). Six hours after returning, he went to work in the field. He then presented fatigue, cough, chest pain, dyspnea, and subcutaneous emphysema. Case 2 was a 17-year-old man who returned home (3,140 m a.s.l.) two weeks after staying at sea level (Barranca). Twelve hours after returning, he went to work in the field. He then presented cough, dyspnea, chest pain, sore throat, and subcutaneous emphysema. Both patients developed hypoxemia, and SPM was diagnosed with the help of chest X-rays. Case 2 was associated with mild high-altitude pulmonary edema. Both patients had no previous history of trauma, illicit drug use, comorbidity, and high-altitude-related diseases. Disease management was conservative, symptomatic, supportive, and based on clinical observation. When a healthy young patient comes to an emergency department because of chest pain, dyspnea, and subcutaneous emphysema, we should consider the possibility of SPM and immediately request frontal and lateral chest X-rays that include the cervical region. A differential diagnosis enables physicians to provide adequate and accurate treatment to patients with SPM.

Oxygen therapy limiting peripheral oxygen saturation to 89-93% is associated with a better survival prognosis for critically ill COVID-19 patients at high altitudes.

Patients admitted to the Intensive Care Unit (ICU) with acute hypoxemic respiratory failure automatically receive oxygen therapy to improve inspiratory oxygen fraction (FiO2). Supplemental oxygen is the most prescribed drug for critically ill patients regardless of altitude of residence. In high altitude dwellers (i.e. in La Paz [≈3,400 m] and El Alto [≈4,150 m] in Bolivia), a peripheral oxygen saturation (SatpO2) of 89-95% and an arterial partial pressure of oxygen (PaO2) of 50-67 mmHg (lower as altitude rises), are considered normal values ​​for arterial blood. Consequently, it has been suggested that limiting oxygen therapy to maintain SatpO2 around normoxia may help avoid episodes of hypoxemia, hyperoxemia, intermittent hypoxemia, and ultimately, mortality. In this study, we evaluated the impact of oxygen therapy on the mortality of critically ill COVID-19 patients who permanently live at high altitudes. A multicenter cross-sectional descriptive observational study was performed on 100 patients admitted to the ICU at the "Clinica Los Andes" (in La Paz city) and "Agramont" and "Del Norte" Hospitals (in El Alto city). Our results show that: 1) as expected, fatal cases were detected only in patients who required intubation and connection to invasive mechanical ventilation as a last resort to overcome their life-threatening desaturation; 2) among intubated patients, prolonged periods in normoxia are associated with survival, prolonged periods in hypoxemia are associated with death, and time spent in hyperoxemia shows no association with survival or mortality; 3) the oxygenation limits required to effectively support the intubated patients' survival in the ICU are between 89% and 93%; 4) among intubated patients with similar periods of normoxemic oxygenation, those with better SOFA scores survive; and 5) a lower frequency of observable reoxygenation events is not associated with survival. In conclusion, our findings indicate that high-altitude patients entering an ICU at altitudes of 3,400 - 4,150 m should undergo oxygen therapy to maintain oxygenation levels between 89 and 93 %.

Comparison of cytokines levels among COVID-19 patients living at sea level and high altitude.

BACKGROUND: At the end of 2019, a novel coronavirus denominated SARS-CoV-2 rapidly spread through the world causing the pandemic coronavirus disease known as COVID-19. The difference in the inflammatory response against SARS-CoV-2 infection among people living at different altitudes is a variable not yet studied. METHODS: A descriptive cross-sectional study was performed in two Peruvian cities at different altitudes for comparison: Lima and Huaraz. Five important proinflammatory cytokines were measured including: IL-6, IL-2, IL-10, IFN-γ and TNF-α using ELISA assays. RESULTS: A total of 35 COVID-19 patients and 10 healthy subjects were recruited from each study site. The mean levels of IL-6 (p < 0.03) and TNF-α (p < 0.01) were significantly different among the study groups. In the case of IL-6, patients from Lima had a mean level of 16.2 pg/ml (healthy) and 48.3 pg/ml (COVID-19), meanwhile, patients from Huaraz had levels of 67.3 pg/ml (healthy) and 97.9 pg/ml (COVID-19). Regarding TNF-α, patients from Lima had a mean level of 25.9 pg/ml (healthy) and 61.6 pg/ml (COVID-19), meanwhile, patients from Huaraz had levels of 89.0 pg/ml (healthy) and 120.6 pg/ml (COVID-19). The levels of IL-2, IL-10 and IFN-γ were not significantly different in the study groups. CONCLUSION: Patients with COVID-19 residing at high-altitude tend to have higher levels of inflammatory cytokines compared to patients living at sea level, particularly IL-6 and TNF-α. A better understanding of the inflammatory response in different populations can contribute to the implementation of therapeutic and preventive approaches. Further studies evaluating more patients, a greater variety of cytokines and their clinical impact are required.

Low serum erythropoietin levels are associated with fatal COVID-19 cases at 4,150 meters above sea level.

Previous studies suggested that erythropoietin (EPO) may protect against severe COVID-19-induced injuries, ultimately preventing mortality. This hypothesis is based on the fact that, in addition to promoting the increase in red blood cells, EPO is an anti-inflammatory, anti-apoptotic and protective factor in several non-erythropoietic tissues. Furthermore, EPO promotes nitric oxide production in the hypoxic lung and stimulates ventilation by interacting with the respiratory centers of the brainstem. Given that EPO in the blood is increased at high-altitude, we evaluated the serum levels of EPO in critical patients with COVID-19 at "Hospital Agramont" in the city of El Alto (4150 masl) in Bolivia. A total of 16 patients, 15 men, one woman, with a mean age of 55.8 ± 8.49 years, admitted to the Intensive Care Unit were studied. All patients were permanent residents of El Alto, with no travel history below 3000 masl for at least one year. Blood samples were collected upon admission to the ICU. Serum EPO concentration was assessed using an ELISA kit, and a standard technique determined hemoglobin concentration. Only half of the observed patients survived the disease. Remarkably, fatal cases showed 2.5 times lower serum EPO than survivors (2.78 ± 0.8643 mU/mL vs 7.06 ± 2.713 mU/mL; p = 0.0096), and 1.24 times lower hemoglobin levels (13.96 ± 2.56 g/dL vs 17.41 ± 1.61 g/dL; p = 0.0159). While the number of cases evaluated in this work is low, our findings strongly warrant further investigation of EPO levels in COVID-19 patients at high and low altitudes. Our results also support the hypothesis that exogenous EPO administration could help critically ill COVID-19 patients overcome the disease.

Acute Lung Edema as a Presentation of Severe Acute Reentry High-Altitude Illness in a Pediatric Patient.

Acute high-altitude pulmonary edema (HAPE) is a pathology involving multifactorial triggers that are associated with ascents to altitudes over 2,500 meters above sea level (m). Here, we report two pediatric cases of reentry HAPE, from the city of Huaraz, Peru, located at 3,052 m. The characteristics of both cases were similar, wherein acclimatization to sea level and a subsequent return to the city of origin occurred, and we speculate that it was caused by activation of predisposing factors to HAPE. The diagnosis and management associated with pulmonary hypertension became a determining factor for therapy.

Down-Turner Syndrome: A Case with Double Monoclonal Chromosomal Abnormality.

Introduction. The coexistence of Down and Turner syndromes due to double chromosome aneuploidy is very rare; it is even more rare to find the presence of a double monoclonal chromosomal abnormality. Objective. To report a unique case of double monoclonal chromosomal abnormality with trisomy of chromosome 21 and an X ring chromosome in all cells studied; no previous report has been found. Case Report. Female, 28 months old, with pathological short stature from birth, with the following dysmorphic features: tilted upward palpebral fissures, short neck, brachycephaly, and low-set ears. During the neonatal period, the infant presented generalized hypotonia and lymphedema of hands and feet. Karyotype showed 47,X,r(X),+21 [30]. Conclusion. Clinical features of both Down and Turner syndromes were found, highlighting short stature that has remained below 3 z score from birth to the present, associated with delayed psychomotor development. G-banded karyotype analysis in peripheral blood is essential for a definitive diagnosis.