Related factors for ProSeal™ laryngeal mask airway failure / Factores relacionados con insuficiencia de las vías respiratorias con el uso de ProSeal™ laryngeal mask

Abstract Introduction: The laryngeal mask airway (LMA) is a device for airway management that is easy to insert, safe, and efficient. However, there are associated complications that can lead to important patient morbidity and mortality, as ventilator failure, can occur with reported incidence between 0.2% and 4.7%. Male gender, advanced age, obesity, short thyromental distance, and poor dentition are known related factors to LMA failure. Objective: Determine the incidence of ProSeal™ LMA ventilatory failure and identify clinical related conditions. Materials and methods: Observational analytic study a group of adult patients with ProSealTM laryngeal mask for airway management. Statistical analysis was performed using STATA 12.1 software. Bivariate analysis was done using Fisher's exact test or Chi2 as it corresponded with statistical significance defined as P value <0.05. Skewed logistic regression for multivariate analysis was performed for estimating adjusted odd ratios (ORs). Results: Incidence of ProSealTM LMA ventilatory failure was 5.2%. In the group of patients that presented failure, 69 were older than 75 years (OR=1.06, 95% confidence interval [CI] 1.03-1.09, P < 0.001), 6 (23.1%) thyromental distance less than 6 x0200A;cm (OR = 2.48, 95% CI 0.93-6.62, P = 0.069), 5 (19.2%), inadequate anesthetic depth and/or laryngospasm (OR=5.78, 95% CI 2.23-14.96, P< 0.001) and 9 (34.6%) vintraoperative use of neuromuscular blockers (NMB) (OR=2.35, 95% CI 1.06-5.21, P=0.035). Conclusion: In patients with LMA management, the age, intraoperative use of NMB and inadequate anesthetic depth and/ or laryngospasm are clinical related conditions for ProSealTMLMA ventilatory failure.

Resumen Introducción: La mascarilla laríngea de vía aérea (LMA) es un dispositivo para el manejo de la vía aérea fácil de insertar, seguro y eficiente. Sin embargo, hay complicaciones asociadas que pueden llevar a morbilidad y mortalidad del paciente, como la falla del respirador, con una incidencia reportada de entre el 0.2% y el 4.7%. El sexo masculino, la edad avanzada, la obesidad, la corta distancia tiromentoniana y la mala dentición son factores conocidos relacionados con el fracaso de la LMA. Objetivo: Determinar la incidencia de la insuficiencia respiratoria con ProSeal™ LMA e identificar las condiciones clínicas relacionadas. Materiales y métodos: Estudio analítico observacional de un grupo de pacientes adultos con uso de ProSeal™ Laryngeal Mask para el manejo de las vías respiratorias. El análisis estadístico se realizó utilizando el software STATA 12.1©. El análisis bivariado se realizó utilizando la prueba exacta de Fisher o Chi2, ya que correspondía a la significación estadística definida como valor de p < 0.05. Se realizó una regresión logística sesgada para el análisis multivariado, con el fin de estimar las proporciones impares ajustadas (OR). Resultados: La incidencia de fallo ventilatorio de ProSeal™ LMA fue del 5.2%. En el grupo de pacientes que presentaron fracaso, 69 eran mayores de 75 años (OR = 1.06; IC del 95%: 1.03 a 1.09; p < 0.001), 6 pacientes (23.1%) tenían distancia tiromentoniana inferior a 6 cm (OR = 2.48; IC del 95%: 0.93 a 6.62, p = 0.069), 5 (19.2%) presentaron profundidad inadecuada del anestésico y/o laringoespasmo (OR = 5.78; IC del 95%: 2.23 a 14.96; p < 0.001) y en 9 (34.6%) hubo uso intraoperatorio de NMB (OR = 2.35; IC del 95%: 1.06 a 5.21; p = 0.035). Conclusión: En pacientes con manejo de la LMA, la edad, el uso intraoperatorio de la NMB y la profundidad anestésica inadecuada y/o laringoespasmo son condiciones clínicas relacionadas con la insuficiencia respiratoria de la LMA ProSeal™.

Animal and clinical trials on a prototype, pressure limited, time cycled Philippine ventilator (PhilVent)

OBJECTIVE:To test the efficacy and safety of PhilVent™, a pressure limited, time cycled, Philippine ventilator through animal and clinical studies. METHODS AND RESULTS: Animal study: Term, newborn piglets (N=8) were intubated and alternately cycled to the PhilVent™ or to a pressure limited, time cycled, commercial ventilator (Sechrist) at peak inspiratory pressures of 10, 13 and 15 cm H20 and rates of 15, 20, 25 breaths per min and constant FiO2 (0.40) and positive end expiratory pressure (+4). Blood gases and adverse events (pneumothorax, sudden deterioration, death) were monitored. Results show no significant difference in blood gases on either machine at the various ventilator settings. No adverse events occurred. Clinical study: Prospective, randomized, controlled trial of 90 preterm infants with respiratory distress, randomized either to PhilVent™ (N=45) or Sechrist (N=45). Ventilator settings were adjusted to achieve predetermined range of blood gases. Arterial blood gases and any adverse events e.g., pneumothorax, pulmonary hemorrhage were monitored. There were no clinically significant differences in the ventilator settings or blood gases of the infants on the PhilVent™ or Sechrist. No increase in adverse events were noted with the PhilVent™. CONCLUSION: In animal and clinical studies, the efficacy and safety of the PhilVent were comparable to the Sechrist. The PhilVent™ is an effective, alternative ventilator for the treatment of respiratory insufficiency in newborn infants.