RESUMO
Introducción. La crisis miasténica es la complicación más grave que sufren los pacientes con Miastenia Gravis. Esta enfermedad se caracteriza clínicamente por debilidad muscular generalizada, que particularmente mejora con el reposo y empeora con el ejercicio debido al agotamiento de la conducción nerviosa a nivel post sináptico. El manejo de la crisis miasténica tiene como piedra angular tratar la causa desencadenante, así como utilizar los fármacos de acción rápida y los descritos en la literatura para enfrentar este escenario, como la plasmaféresis, inmunoglobulinas o terapia biológica. Además, es crucial tener un adecuado manejo desde el punto de vista ventilatorio manteniendo la protección pulmonar y sobre todo diafragmática, con las herramientas disponibles en la actualidad al lado de la cama del paciente. Asimismo, el weaning o destete del ventilador mecánico debe llevarse a cabo de manera objetiva y bajo evaluaciones específicas para lograr un desenlace optimo.
Introduction. Myasthenic crisis is the most serious complication suffered by patients with Myasthenia Gravis. This disease is clinically characterized by generalized muscle weakness, which particularly improves with rest and worsens with exercise due to depletion of nerve conduction at the post-synaptic level. The cornerstone of managing myasthenic crisis is treating the triggering cause, as well as using fast-acting drugs and interventions described in the literature to deal with this scenario, such as plasmapheresis, immunoglobulins, or biological therapy. In addition, it is imperative to ensure adecuate management from the ventilatory perspective, preserving lung function and safeguarding the diaphragm with the tools currently available at the patient's bedside. Likewise, weaning from the mechanical ventilator must be conducted objectively and guided by specific evaluations to achieve an optimal outcome.
RESUMO
BACKGROUND: Prone positioning is currently applied in time-limited daily sessions up to 24 h which determines that most patients require several sessions. Although longer prone sessions have been reported, there is scarce evidence about the feasibility and safety of such approach. We analyzed feasibility and safety of a continuous prolonged prone positioning strategy implemented nationwide, in a large cohort of COVID-19 patients in Chile. METHODS: Retrospective cohort study of mechanically ventilated COVID-19 patients with moderate-to-severe acute respiratory distress syndrome (ARDS), conducted in 15 Intensive Care Units, which adhered to a national protocol of continuous prone sessions ≥ 48 h and until PaO2:FiO2 increased above 200 mm Hg. The number and extension of prone sessions were registered, along with relevant physiologic data and adverse events related to prone positioning. The cohort was stratified according to the first prone session duration: Group A, 2-3 days; Group B, 4-5 days; and Group C, > 5 days. Multivariable regression analyses were performed to assess whether the duration of prone sessions could impact safety. RESULTS: We included 417 patients who required a first prone session of 4 (3-5) days, of whom 318 (76.3%) received only one session. During the first prone session the main adverse event was grade 1-2 pressure sores in 97 (23.9%) patients; severe adverse events were infrequent with 17 non-scheduled extubations (4.2%). 90-day mortality was 36.2%. Ninety-eight patients (24%) were classified as group C; they exhibited a more severe ARDS at baseline, as reflected by lower PaO2:FiO2 ratio and higher ventilatory ratio, and had a higher rate of pressure sores (44%) and higher 90-day mortality (48%). However, after adjustment for severity and several relevant confounders, prone session duration was not associated with mortality or pressure sores. CONCLUSIONS: Nationwide implementation of a continuous prolonged prone positioning strategy for COVID-19 ARDS patients was feasible. Minor pressure sores were frequent but within the ranges previously described, while severe adverse events were infrequent. The duration of prone session did not have an adverse effect on safety.
