Frequency of hypoxic events in patients on a mechanical ventilator

Abstract

Background:Mechanical ventilation is an important tool in the management of respiratory failure in the critically ill patient. Although mechanical ventilation can be a life-saving intervention, it is also known to carry several side-effects and risks. Adequate oxygenation is one of the primary goals of mechanical ventilation. However, while on mechanical ventilation, patients frequently experience hypoxic events resulting from various causes, which need to be properly evaluated and treated.Materials and Methods:Data were obtained by prospectively reviewing all intensive care admissions during the period from March 2009 to March 2010 at a 651-bed urban medical center. Patients who developed hypoxemia (oxygen saturation ≤88% and a PaO2≤60 torrs) while on mechanical ventilation were investigated for the cause of hypoxic event.Results:During the study period, 955 patients required mechanical ventilation from which 79 developed acute hypoxia. The causes of acute hypoxia in decreasing order of occurrences were pulmonary edema, atelectasis, pneumothorax, pneumonia, ARDS, endotracheal tube malfunction, airway bleeding, and pulmonary embolism.Conclusions:Appropriate evaluation of all hypoxic events must begin at the bedside. A step-by-step approach must include a thorough physical examination. Evaluation of the endotracheal tube can immediately reveal dislodgement, bleeding, and secretions. Correlation of physical examination findings with those on chest radiograph is essential. Each hypoxic event requires a different intervention depending on its etiology. Instead of simply increasing the fraction of oxygen in the inspired air to overcome hypoxia, a concerted effort in appropriate problem solving can reduce the likelihood of an incorrect diagnosis and management response.

Silencing of Activity During Hypoxia Improves Functional Outcomes in Motor Neuron Networks in vitro

“…In this context, there is a particular association with the activity of NMDA-receptors and findings suggest that blocking them can reduce the production of ROS during hypoxia ( Lafon-Cazal et al, 1993 ) as well as ameliorate post-hypoxic hyperexcitability ( Godukhin et al, 2002 ). When addressing hypoxia and considering interventions it is vital to know what pathways can be targetted in order to improve outcomes for patients, for example those who require assisted ventilation, which can be associated with acute hypoxic events ( Keith and Pierson, 1996 ; Mahmood et al, 2013 ). This study suggests that functional outcomes can be preserved by targetting activity-dependent pathways.…”

Multiple Neuroinvasive Pathways in COVID-19

“…It has been anecdotally noted that COVID-19 patients who spent significant amount of time in intensive care are not infrequently left with residual cognitive impairment, sometimes referred to as “post-intensive care syndrome,” a known condition, which was previously described in intensive care survivors [ 69 ]. The underlying mechanisms are unclear, but hypoxia, while on a mechanical ventilator, must be considered [ 70 ]. This possibility is supported by a recent observation of acute neuropathological changes from hypoxia in the brains of 18 consecutive deaths of ventilator-dependent COVID-19 patients [ 71 ].…”

Manejo integral del paciente con traqueostomía

“…47 Estos cambios favorecen retención de secreciones y aparición de atelectasias; funcionalmente se caracteriza por disminución de la capacidad vital forzada (FVC) y distensibilidad estática, incremento variable en la resistencia de la vía aérea y aparición de hipoxemia con gradiente alvéolo-arterial elevado. 42,[47][48][49][50] Suzukawa et al, propusieron una escala simple para definir las características físicas de las secreciones. Con base en los resultados se pueden tomar decisiones para ajustar la humedad en un paciente con vía aérea artificial (tabla 1).…”

“…73 Existen diversos protocolos de decanulación. 50,72,[74][75][76] La cánula de traqueostomía es retirada cuando existe permeabilidad de la vía aérea y se ha resuelto el problema primario. 73 Ceriana et al, hacen énfasis en el cumplimiento de las siguientes condiciones para su retiro: 1) saturación de oxígeno al aire ambiente mayor a 92%; 2) ausencia de secreciones abundantes; 3) reflejo tusígeno adecuado con flujo pico de tos mayor o igual a 160 L/min; 4) radiografía de tórax sin anormalidades (neumonía, neumotórax, etc.…”