ABSTRACT
Actualmente se reconoce que el índice respiratorio, correspondiente al cociente de la diferencia de presión de dióxido de carbono venosa arterial (DPv-aCO2) sobre la diferencia del contenido de oxígeno arteriovenoso ((DPv-aCO2/DCa-vO2) orienta sobre el gasto cardiaco (flujo sanguíneo micro circulatorio o perfusión) y el metabolismo anaeróbico, respectivamente, que puede ser el objetivo final de la monitorización gasométrica en el paciente en estado crítico.
ABSTRACT
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 ââfor 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 %.
Subject(s)
COVID-19/physiopathology , COVID-19/therapy , Critical Care/standards , Oxygen Inhalation Therapy/standards , Oxygen Saturation/physiology , Adult , Aged , Altitude , Bolivia , Critical Care/methods , Critical Illness , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Oxygen Inhalation Therapy/methodsABSTRACT
La gasometría arterial es fundamental en el diagnóstico y manejo del medio interno. El objetivo es caracterizar los valores de gasometría arterial en gestantes sanas con embarazo normoevolutivo residentes a 4 150 metros sobre el nivel del mar. Serie de casos llevada a cabo durante la gestión 2019, la cual incluye pacientes sin clínica ni antecedentes de enfermedades cardiopulmonares o hematológicas, así como ausencia de tabaquismo y residencia de al menos los últimos 6 meses. Se incluye 30 pacientes, media de edad 25.23 años (desvío estándar 3.69), con edad gestacional media de 26 semanas (desvío estándar 5.5). El valor de pH tiende a ser más alto, así como los valores de PaO2, PaCO2, HCO3 y SatpO2% son más bajos, incluso en comparación con adultos sanos residentes de la misma altitud. Existe cierta tendencia positiva hacia el incremento progresivo del pH mientras la edad gestacional avanza. La gasometría arterial en la altura, debe ser interpretada con suma precaución en relación a las condiciones barométricas, proporcionándose así, valiosa información con aplicación a la obstetricia crítica a muy alta altitud.
Arterial blood gases analysis is essential in the diagnosis and management of pathologies. The objective is to characterize arterial blood gases values in healthy pregnant residents at 4150 meters above sea level. Series case performed during 2019, including patients without a clinical features or antecedents of cardiopulmonary or hematological diseases as well as absence of smoking and residence for at least the last 6 months. Thirty patients are included, mean age 25.23 years (standard deviation 3.69), with average gestational age of 26 weeks (standard deviation 5.5). The pH tends to be higher, as well as the values of PaO2, PaCO2, HCO3 and SatpO2% are lower, even compared to healthy adults living at the same altitude. There is some positive trend towards progressive pH is higher such as gestational age progresses. Arterial gas blood analysis at altitude, should be interpreted with extreme caution in relation to barometric conditions, thus providing, valuable information to critical care obstetrics at very high altitude
