Cánula Nasal de Alto Flujo Asimétrica: una Revisión Narrativa / Asymmetrical High Flow Nasal Cannula: a Narrative Review

Los sistemas de Cánula nasal de alto flujo (CNAF) han sido ampliamente utilizados en el campo clínico como soporte no invasivo en el manejo de la falla respiratoria aguda (sobre todo hipoxémica) y cuidados post extubación. Clínica y fisiológicamente, las cánulas nasales de alto flujo son capaces de entregar un flujo de oxigeno alto que, debido a que ese gas se encuentra optimamente humidificado y calefaccionado, permite una mejor tolerancia por parte del paciente al ser comparada con las cánulas de oxigeno tradicionales. Por otra parte, este alto. Flujo es capaz de generar una presión positiva al final de la espiración (CPAP) en la vía área y favorecer tanto en barrido de dióxido de carbono (CO2) desde la vía aérea superior, lo que disminuye el trabajo respiratorio del paciente y mejora su confort.. Sin embargo; aún existe un alto porcentaje de pacientes que fracasan la terapia con CNAF y requiere soportes mas complejos como la ventilación mecánica, ya sea imvasiva o no. Estos resultados con la terapia CNAF pueden ser influidos por aspectos técnicos como, por ejemplo, la turbulencia que pueden generar estos sistemas a nivel de la región nasal. Por esta razón se han desarrollado nuevas tecnologías en el diseño y uso de interfaces para suministrar este alto flujo. Una de estas innovaciones es el uso de cánulas asimétricas, las que potencian los beneficios fisiológicos que entrega una cánula de alto flujo convencional. La presente revisión pretende exponer las principales diferencias que presenta el sistema de alto flujo convencional versus la nueva interface asimétrica.

High-flow nasal cannula (HFNC) systems have been widely used in the clinical field as non-invasive support in the management of acute respiratory failure (especially hypoxemic) and post-extubation care. Clinically and physiologically, high flow nasal cannulas are capable of delivering a high flow of oxygen which, because this gas is optimally humidified and heated, allows better tolerance by the patient when compared to traditional oxygen cannulas. . On the other hand, this high. Flow is capable of generating positive pressure at the end of expiration (CPAP) in the airway and favoring the sweep of carbon dioxide (CO2) from the upper airway, which reduces the patient's respiratory work and improves their comfort. .. However; There is still a high percentage of patients who fail therapy with HFNC and require more complex supports such as mechanical ventilation, whether invasive or not. These results with HFNC therapy can be influenced by technical aspects such as, for example, the turbulence that these systems can generate in the nasal region. For this reason, new technologies have been developed in the design and use of interfaces to provide this high flow. One of these innovations is the use of asymmetric cannulas, which enhance the physiological benefits provided by a conventional high-flow cannula. The present review aims to expose the main differences that the conventional high flow system presents versus the new asymmetric interface.

Performance Evaluation of Geometrically Different Pediatric Arterial Cannulae in a Pediatric Cardiopulmonary Bypass Model

ABSTRACT Objective: To define a reference chart comparing pressure drop vs. flow generated by a set of arterial cannulae currently utilized in cardiopulmonary bypass conditions in pediatric surgery. Methods: Cannulae from two manufacturers were selected considering their design and outer and inner diameters. Cannula performance was evaluated in terms of pressure drop vs. flow during simulated cardiopulmonary bypass conditions. The experimental circuits consisted of a Jostra HL-20 roller pump, a Quadrox-i pediatric oxygenator (Maquet Cardiopulmonary AG, Rastatt, Germany), and a custom pediatric tubing set. The circuit was primed with lactated Ringer's solution only (first condition) and with human packed red blood cells added (second condition) to achieve a hematocrit of 30%. Cannula sizes 8 to 16 Fr were inserted into the cardiopulmonary bypass circuit with a "Y" connector. The flow was adjusted in 100 ml/min increments within typical flow ranges for each cannula. Pre-cannula and post-cannula pressures were measured to calculate the pressure drop. Results: Utilizing a pressure drop limit of 100 mmHg, our results suggest a recommended flow limit of 500, 900, 1400, 2600, and 3100 mL/min for Braile arterial cannulae sizes 8, 10, 12, 14, and 16 Fr, respectively. For Medtronic DLP arterial cannulae sizes 8, 10, 12, 14, and 16 Fr, the recommended flow limit is 600, 1100, 1700, 2700, and 3300 mL/min, respectively. Conclusion: This study reinforces discrepancies in pressure drop between cannulae of the same diameter supplied by different manufacturers and the importance of independent translational research to evaluate components' performance.

High-flow nasal cannula and non-invasive mechanical ventilation in pediatric asthma exacerbation: two-year prospective observational study in intensive care / Cánula nasal de alto flujo y ventilación no invasiva en asma pediátrico grave: estudio observacional prospectivo de dos años de duración en cuidados intensivos

Abstract Background: Asthma is a common cause of admission to the pediatric intensive care unit (PICU). We described and analyzed the therapies applied to children admitted to a tertiary PICU because of asthma. Later, we evaluated high-flow nasal cannula (HFNC) use in these patients and compared their evolution and complications with those who received non-invasive ventilation. Methods: We conducted a prospective observational study (October 2017-October 2019). Collected data: epidemiological, clinical, respiratory support therapy needed, complementary tests, and PICU and hospital stay. Patients were divided into three groups: (1) only HFNC; (2) HFNC and non-invasive mechanical ventilation (NIMV); and (3) only NIMV. Results: Seventy-six patients were included (39 female). The median age was 2 years and 1 month. The median pulmonary score was 5. The median PICU stay was 3 days, and the hospital stay was 6 days. Children with HNFC only (56/76) had fewer PICU days (p = 0.025) and did not require NIMV (6/76). Children with HFNC had a higher oxygen saturation/fraction of inspired oxygen ratio ratio (p = 0.025) and lower PCO2 (p = 0.032). In the group receiving both therapies (14/76), NIMV was used first in all cases. No epidemiologic or clinical differences were found among groups. Conclusion: HFNC was a safe approach that did not increase the number of PICU or hospital days. On admission, normal initial blood gases and the absence of high oxygen requirements were useful in selecting responders to HFNC. Further randomized and multicenter clinical trials are needed to verify these data.

Resumen Introducción: El asma es una causa frecuente de ingreso en la unidad de cuidados intensivos pediátricos (UCIP). En este, cuadro el uso de cánula nasal de alto flujo (CNAF) se ha visto extendido. En este trabajo se describe el tratamiento global en la UCIP ante el ingreso por asma en un hospital monográfico pediátrico y se evalúa la respuesta al uso de la CNAF, comparando la evolución de los pacientes con aquellos que recibieron ventilación no invasiva (VNI). Métodos: Se llevó a cabo un estudio observacional prospectivo (de octubre del 2017 a octubre del 2019). Se describieron epidemiología, clínica, tratamiento y soporte respiratorio. Para la comparación se crearon tres grupos de pacientes: 1) solo CNAF; 2) CNAF y VNI; y 3) solo VNI. Resultados: Se incluyeron 76 pacientes. La mediana de edad fue de dos años y un mes; la mediana de índice pulmonar fue 5. La mediana de ingreso en UCIP fue de tres días y de ingreso hospitalario, seis días. Los niños con solo CNAF (56/76) mostraron menos días de UCIP (p = 0.025) y no requirieron VNI (6/76). También mostraron mayor SatO2/FiO2 (saturación de oxígeno/fracción de oxígeno inspirado) (p = 0.025) y menor nivel de PCO2 (presión parcial de CO2) (p = 0.032). La VNI se utilizó primero siempre en el grupo que recibió ambas modalidades (14/76). No se encontraron diferencias epidemiológicas o clínicas entre grupos. Conclusiones: En nuestra serie, el uso de CNAF no aumentó los días de ingreso en la UCIP ni de hospital. Tampoco requirió cambio a VNI. Al ingreso, una gasometría normal y bajo requerimiento de oxígeno permitieron seleccionar a los pacientes respondedores. Se necesitan más ensayos multicéntricos clínicos aleatorizados para verificar estos datos.

Uso de cánula nasal de alto flujo artesanal como oxigenoterapia en insuficiencia respiratoria por COVID-19 / Use of artisanal high flow nasal cannula as oxygen therapy in respiratory failure due to COVID-19

Los riesgos asociados a la neumonía por (SARS-CoV-2) es la generación de insuficiencia respiratoria secundaria que en algunos casos desencadenara al tan temido síndrome de distres respiratorio (SDRA); Informes sobre atención clínica, indican que tiene una incidencia (SDRA) de 3-10 % con necesidad de Asistencia Respiratoria Mecánica (ARM) en pacientes hospitalizados; por lo que dispositivos de oxigenación no invasivos siguen siendo una opción atractiva, de forma inicial. Caso clínico: mujer de 47 años con insuficiencia respiratoria secundario a neumonía por COVID-19, por la gravedad se indica su ingreso a terapia intensiva, pero por razones de falta de unidad es manejada en unidad respiratoria, con el uso de dispositivos de oxigenación de armado ARTESAL, de manera exitosa, con la utilización de CNAF-artesanal, se pretende mejorar el trabajo respiratorio, índices de oxigenación, mientras se da tratamiento a la infección por el COVID-19; el objetivo del presente caso es reportar el presente caso con evolución favorable a la literatura disponible. Discusión: El uso de terapia de oxigenación con dispositivo de Cánula Nasal de Alto Flujo, aún no ha sido normatizado en pacientes con COVID-19, pero existe evidencia clínica sobre los efectos beneficiosos en la insuficiencia respiratoria en neonatos mas no en adultos. Conclusión: El uso temprano de la CNAF-artesanal en la insuficiencia respiratoria resulta muy atractivo, más aún con dispositivo de confección artesanal, da una opción más al paciente fuera de UTI, pudiendo apoyar en evitar la intubación y su ingreso a ventilación mecánica.

The risks associated with pneumonia (SARS-CoV-2) is the generation of secondary respiratory failure that in some cases will trigger the much feared respiratory distress syndrome (ARDS); Reports on clinical care indicate that it has an incidence (ARDS) of 3-10% with the need for Mechanical Respiratory Assistance (ARM) in hospitalized patients; so non-invasive oxygenation devices remain an attractive option, initially. Clinical case: a 47-year-old woman with respiratory failure secondary to covid-19 pneumonia. Due to the severity, her admission to intensive care is indicated, but for reasons of lack of unity, she is managed in a common room, with the use of high-pressure oxygenation devices. ARTISAL assembly, successfully, with the use of CNAF-artisanal, is intended to improve the work of breathing, and oxygenation indices, while treating the infection by COVID-19; The objective of this case is to report the present case with a favorable evolution based on the available literature. Discussion: The use of oxygenation therapy with a High Flow Nasal Cannula device has not yet been standardized in patients with COVID-19, but there is clinical evidence on the beneficial effects in respiratory failure in neonates but not in adults. Conclusion: The early use of the artisan HFNC in respiratory failure is very attractive, even more so with an artisanal device, it gives the patient another option outside the ICU, being able to help avoid intubation and admission to mechanical ventilation.

Origen y evolución de una vía aérea permeable / The origin and evolution of a permeable airway

Resumen: A través de los siglos hemos descubierto la importancia de mantener permeable y segura la vía aérea. Desde Hipócrates en la antigua Grecia, hasta el siglo XX en oriente y occidente, se ha continuado con el desarrollo de herramientas que faciliten esta cotidiana tarea por lo que, con esta revisión sistemática, se establecieron como objetivos exponer el origen y los antecedentes del tubo endotraqueal, cánula orofaríngea y laringoscopio, así como discutir su utilidad en la práctica anestésica-quirúrgica, a través del tiempo hasta hoy en día.

Abstract: Over the centuries, we have discovered the importance of preserving a safe permeable airway. From Hippocrates in ancient Greece to the 20th century in the East and West, the development of multiple tools that enable this task continues through time, which is why with this systematic review we aim to uncover the origin and historical background of the endotracheal tube, the oropharyngeal cannula and the laryngoscope, discussing their effectiveness in the anesthetic-surgical practice over years to the present day.

Early clinical application and prediction of ROX index in patients with high-flow nasal canula oxygen therapy / 中华危重病急救医学

Objective:To investigate the application value of ROX index in evaluating the effect of high-flow nasal cannula oxygen therapy (HFNC) on patients diagnosed with respiratory failure, and to find a simpler and more effective method to observe the efficacy of HFNC.Methods:A retrospective cohort study was conducted. Patients who were admitted to department of critical care medicine of the Tianjin Third Central Hospital from April 2020 to August 2022, diagnosed with type Ⅰ respiratory failure, and treated with HFNC after failure of conventional oxygen therapy were enrolled. Oxygenation index (PaO 2/FiO 2), fraction of inspired oxygen (FiO 2), gas flow rate at the initial time of admission, and pulse oxygen saturation (SpO 2), FiO 2 and respiratory rate (RR) at 2, 4, 6, 8, 10 and 12 hours of HFNC were collected, and ROX index was calculated. The patients with symptoms and PaO 2/FiO 2 improved after HFNC treatment and without higher respiratory support lately were defined as HFNC success, while other patients with symptoms worsening and needing follow-up non-invasive positive pressure ventilation (NIPPV) or invasive positive pressure ventilation (IPPV) were defined as HFNC failure. The tendency of changes in the ROX index at each time point was observed. Receiver operator characteristic curve (ROC curve) was plotted to obtain the optimum cut-off value of ROX index for predicting HFNC outcome and the optimal monitoring time point for HFNC. Results:A total of 142 patients were eventually enrolled, among whom 96 patients (67.61%) were in treated with HFNC successfully, while 46 patients (32.39%) were recorded as HFNC failure (39 patients and 7 patients received NIPPV or IPPV, respectively), with an overall intubation rate of 4.93% (7/142). Compared with the HFNC success group, the HFNC failure group had lower PaO 2/FiO 2 [mmHg (1 mmHg ≈ 0.133 kPa): 208.8±37.3 vs. 235.7±48.3, P < 0.01] and higher initial gas flow rate (L/min: 46.4±3.9 vs. 42.3±4.9, P < 0.01). However, there was no significant difference in gender, age, primary diagnosis, severity of disease, hemoglobin (Hb), C-reactive protein (CRP), and brain natriuretic peptide (BNP) between the two groups. In the HFNC failure group, there were 12 patients (26.09%) received progressive oxygen therapy within 12 hours of HFNC, of which 3 patients (6.52%) occurred within 6 hours, while the other 9 patients (19.57%) occurred after 6 hours. The initial ROX index was not statistically significant between the two groups. Both groups showed a continuous increasing ROX index with longer treatment duration of HFNC, and the ROX index at all of the time points of the HFNC failure group was significantly lower than that of the HFNC success group with statistically significant difference (2 hours: 9.39±2.85 vs. 10.91±3.51, 4 hours: 8.62±2.29 vs. 11.40±3.18, 6 hours: 7.62±1.65 vs. 11.85±3.45, 8 hours: 7.79±1.59 vs. 11.62±3.10, 10 hours: 7.97±1.62 vs. 12.44±2.75, 12 hours: 8.84±2.51 vs. 12.45±3.03, all P < 0.05). The ROC curve analysis showed that the areas under the ROC curve (AUC) of ROX index assessing the effect of HFNC at the time of treating 6, 8 and 10 hours were better than 2, 4 and 12 hours (0.890, 0.903, 0.930 vs. 0.585, 0.738 and 0.829), indicating that the ROX index could determine the efficacy at the early stage of HFNC (within 6 hours). When the optimum cut-off value of ROX index was 8.78, the sensitivity was 90.6%, and the specificity was 76.5%. Conclusion:The ROX index at 6 hours of HFNC has a certain predictive value for the efficacy of HFNC with an optimum cut-off value of 8.78, which can provide clinical health care personnel a method for observing the efficacy of HFNC, and guide the correct selection of oxygen therapy modality at an early stage and timely adjustment of oxygen therapy strategy.

Research progress on anhepatic phase in rat liver transplantation / 器官移植

With persistent advancement of surgical instruments, methods and techniques, clinical efficacy of liver transplantation has been steadily enhanced. However, the length of anhepatic phase is still an important factor affecting the efficacy of liver transplantation. Rat is one of the major animal models for liver transplantation-related basic research. In this article, multiple approaches for prolonging the anhepatic phase and shortening the operation time during anhepatic phase in rat liver transplantation were reviewed, which consisted of sevoflurane inhalation anesthesia, intravenous infusion via jugular vein indwelling needle, clamping of the abdominal aorta before anhepatic phase, injection of normal saline into portal vein before anhepatic phase, subcutaneous transposition of the spleen, electrocoagulation of hepatic esophageal artery, magnetic ring anastomosis of the superior and inferior hepatic vena cava, cannula anastomosis of the superior and inferior hepatic vena cava, stent anastomosis of the superior and inferior hepatic vena cava, rapid connection device and cannula of portal vein, and ring-shaped cannula of hepatic tissue-preserving inferior hepatic vena cava, aiming to add evidence for prolonging the duration of anhepatic phase, improving the operation efficiency during anhepatic phase and elevating the success rate of rat liver transplantation.

Applications of different flow rates of humidified high flow nasal cannula oxygen therapy on ICU patients with difficult weaning / 中国实用护理杂志

Objective:To explore the effects of different initial flow rates of humidified high flow nasal cannula oxygen therapy on weaning outcomes and comfort level among ICU patients with difficult weaning.Methods:A total of 99 ICU patients with difficult weaning received at Guangzhou Red Cross Hospital ICU from June 2019 to June 2021 were enrolled in the present study, they were assigned to 40 L/min group, 50 L/min group and 60 L/min group according to the random number table method, with 33 cases in each group. The weaning outcomes among three groups were compared, the degree of dryness of oral/nasal cavity, throat pain as well as vital signs and blood gas indexes were also compared before extubation and 30 min after the first humidified high flow nasal cannula (HHFNC) oxygen therapy.Results:There was no significant difference in length of stay in ICU and hospital, re-intubation within 7 days, the mortality within 28 days in ICU and the hospital among three groups ( P>0.05). The weaning success rate were 78.8% (24/33) and 77.4% (23/31) in 50 L/min group and 60 L/min, higher than in the 40 L/min group 53.1% (17/32), the difference was statistically significant ( χ2=4.78, 4.09, both P<0.05). After oxygen therapy, the scores of dryness of oral/nasal cavity and throat pain in the 40 L/min group, 50 L/min group and 60 L/min group were (3.16 ± 0.77), (2.94 ± 0.80) and (3.27 ± 0.92), (3.09 ± 0.77), and (4.10 ± 1.01), (3.97 ± 1.40), the differences were statistically significant ( F=5.21, 9.26, both P<0.05), and the differences between 50 L/min group and 40 L/min group and 60 L/min group were statistically significant ( t values were 2.62-3.99, all P<0.05). However, there was no significant difference in vital signs and blood gas indexes among the three groups before extubation and after oxygen therapy ( P>0.05). Conclusions:Humidified high flow nasal cannula oxygen therapy for the ICU patients with difficult weaning, oxygen flow with 50L/min can not only effectively promote weaning success rate but also improve patients′ respiratory comfort level.

Clinical and follow-up study of premature infants with neonatal respiratory distress syndrome managed by the less invasive surfactant administration / 中华实用儿科临床杂志

Objective:To explore the clinical therapeutic effect and follow-up prognosis of preterm infants with neonatal respiratory distress syndrome (NRDS) managed by less invasive surfactant administration (LISA) and traditional intubation-surfactant-extubation (INSURE) of pulmonary surfactant (PS).Methods:Data during hospitalization and follow-up period of 187 NRDS preterm infants (gestational age 24 weeks to 31 + 6 weeks, and birth weight <1 500 g) admitted to the Department of Neonatology, the Women and Children′s Hospital of Chongqing Medical University from March 2019 to February 2021 were retrospectively analyzed.NRDS preterm infants who were injected with PS by LISA were included in the LISA group (144 cases), and those who were injected with PS by INSURE were included in the INSURE group (43 cases). The propensity score matching method was used to correct the confounding factors between groups, and the covariate equilibrium samples between groups were obtained (39 cases in each group). Clinical treatment effect and prognosis of physical development, hearing and vision development, nervous system development, respiratory system diseases and other conditions of the two groups of children were compared using the t test, Chi- square test and other statistical analysis methods as appropriate. Results:(1)Compared with that of the INSURE group, the incidence of BPD [12 cases (33.3%) vs.23 cases (63.9%), χ2=6.727, P=0.009] and ROP [13 cases (36.1%) vs.26 cases (72.2%), χ2=9.455, P=0.002] in the LISA group were significantly lower.The incidence of mild BPD [8 cases (22.2%) vs.16 cases (44.4%), χ2=4.000, P=0.046] and stage Ⅰ-Ⅱ ROP [11 cases (30.6%) vs.22 cases (61.1%), χ2=6.769, P=0.009] in the LISA group was significantly lower than that of the INSURE group.There was no significant difference in the incidence of moderate and severe BPD and stageⅢ ROP and above between groups (all P>0.05). (2)There were no statistical differences in the repeated use of PS, mechanical ventilation rate within 72 h, pneumothorax/pulmonary hemorrhage, grade Ⅲ-Ⅳ periventricula-rintraventricular hemorrhage, stage Ⅱ-Ⅲ neonatal necrotizing enterocolitis, sepsis, abnormal amplitude integrated electroencephalogram, mortality in 36 weeks of corrected gestational age, total oxygen inhalation duration and hospitalization duration between the two groups (all P>0.05). (3)Follow-up within 1 year of corrected age after discharge.There were no significant differences in extrauterine body mass, body length and head circumference development, visual development, hearing development, Neonatal Behavioral Neurological Assessment score at corrected gestational age of 40 weeks, Bayley Scales of Infants Development score at corrected gestational age of 6 months and age of 1 year, pneumonia and re-hospitalization due to respiratory diseases between groups (all P>0.05). Conclusions:PS administration with LISA technology can reduce the incidence of mild BPD and stage Ⅰ-Ⅱ ROP in premature infants with NRDS who had the gestational age of 24-31 + 6 weeks and birth weight<1 500 g, without increasing the risk of other complications.The long-term prognosis of them treated with PS administration with LISA and INSURE is similar.

High-flow nasal cannula oxygen therapy versus non-invasive ventilation for chronic obstructive pulmonary diseases with acute-moderate hypercapnic respiratory failure: a randomized controlled trial of non-inferiority / 中华急诊医学杂志

Objective:To compare the efficacy of high-flow nasal cannula oxygen therapy (HFNC) and non-invasive ventilation (NIV) in the treatment of acute exacerbation of chronic obstructive pulmonary disease (AECOPD) with moderate typeⅡ respiratory failure, to clarify the feasibility of HFNC in the treatment of AECOPD, and to explore the influencing factors of HFNC failure.Methods:This study was a randomized controlled trial of non-inferiority. Patients with AECOPD with moderate type Ⅱ respiratory failure [arterial blood gas pH 7.25-7.35, partial pressure of arterial blood carbon dioxide (PaCO 2)> 50 mmHg] admitted to the Intensive Care Unit (ICU) from January 2018 to December 2021 were randomly assigned to the HFNC group and NIV group to receive respiratory support. The primary endpoint was the treatment failure rate. The secondary endpoints were blood gas analysis and vital signs at 1 h, 12 h, and 48 h, total duration of respiratory support, 28-day mortality, comfort score, ICU length of stay, and total length of stay. Multivariate logistic regression analysis was used to evaluate the failure factors of HFNC treatment. Results:Totally 228 patients were randomly divided into two groups, 108 patients in the HFNC group and 110 patients in the NIV group. The treatment failure rate was 29.6% in the HFNC group and 25.5% in the NIV group. The risk difference of failure rate between the two groups was 4.18% (95% CI: -8.27%~16.48%, P=0.490), which was lower than the non-inferiority value of 9%. The most common causes of failure in the HFNC group were carbon dioxide retention and aggravation of respiratory distress, and the most common causes of failure in the NIV group were treatment intolerance and aggravation of respiratory distress. Treatment intolerance in the HFNC group was significantly lower than that in the NIV group (-29.02%, 95% CI -49.52%~-7.49%; P=0.004). After 1 h of treatment, the pH in both groups increased significantly, PaCO 2 decreased significantly and the oxygenation index increased significantly compared with baseline (all P < 0.05). PaCO 2 in both groups decreased gradually at 1 h, 12 h and 48 h after treatment, and the pH gradually increased. The average number of daily airway care interventions and the incidence of nasal and facial lesions in the HFNC group were significantly lower than those in the NIV group ( P < 0.05), while the comfort score in the HFNC group was significantly higher than that in the NIV group ( P=0.021). There was no significant difference between the two groups in the total duration of respiratory support, dyspnea score, ICU length of stay, total length of stay and 28-day mortality (all P > 0.05). Multivariate logistic regression analysis showed that acute physiology and chronic health evaluation Ⅱ score (≥15), family NIV, history of cerebrovascular accident, PaCO 2 (≥60 mmHg) and respiratory rate (≥32 times/min) at 1 h were independent predictors of HFNC failure. Conclusions:HFNC is not inferior to NIV in the treatment of AECOPD complicated with moderate type Ⅱ respiratory failure. HFNC is an ideal choice of respiratory support for patients with NIV intolerance, but clinical application should pay attention to the influencing factors of its treatment failure.

Uso prolongado de cánula nasal de alto flujo en niños con problemas respiratorios / Prolonged use of high flow nasal cannula in children with respiratory problems

La cánula nasal de alto flujo (CNAF) es una modalidad ventilatoria no invasiva segura y efectiva, usada ampliamente en patología respiratoria aguda en adultos y niños. Objetivo: presentar casos clínicos pediátricos que utilizaron CNAF por tiempo prolongado por problemas respiratorios crónicos. Descripción de casos clínicos, revisión de fichas clínicas de 5 pacientes que utilizaron CNAF por más de 1 mes, entre los años 2017-2020 en el Complejo Asistencial Dr. Sótero del Río. Aprobado por Comité de Ética. Resultados: 5 pacientes varones de mediana 61 (44 a 212) días de edad al inicio del uso de CNAF. Diagnóstico de base: displasia broncopulmonar (2/5), síndrome de Treacher Collins (1/5), síndrome de cimitarra con hipoplasia pulmonar derecha (1/5) y traqueobroncomalacia severa (1/5). Todos requirieron previamente uso de ventilación invasiva o no invasiva con mediana de 59 (4 a 78) días. A todos se les realizó broncoscopia, saturometría contínua o poligrafía para diagnóstico y titulación de CNAF y oxígeno. Todos mejoraron clínicamente, la SpO2 y el número de apneas. Dos pacientes se enviaron a domicilio con uso de Airvo2 nocturno. La mediana de uso de CNAF fue 165 (34 a 445) días. Conclusiones: el uso prolongado de CNAF es útil en pacientes pediátricos seleccionados, bien tolerado y factible de utilizar en domicilio.

The high-flow nasal cannula (HFNC) is a safe and effective non-invasive ventilation support widely used in acute respiratory pathology in adults and children. Objective: To present pediatric clinical cases that used HFNC for an extended period due to chronic respiratory disease. Description of clinical cases, review of medical records of 5 patients who used HFNC for more than 1 month, between the years 2017-2020 at Complejo Asistencial Dr. Sótero del Río. Approved by the Ethics Committee. Results: 5 male patients with a median age of 61 (44 to 212) days at the start of HFNC use. Underlying diagnoses: bronchopulmonary dysplasia (2/5), Treacher Collins syndrome (1/5), Scimitar syndrome with right pulmonary hypoplasia (1/5), and severe tracheobronchomalacia (1/5). All of them previously required invasive or non-invasive ventilation for a median of 59 (4 to 78) days. All patients underwent bronchoscopy, continuous pulse oximetry or polygraphy for diagnosis and titration of HFNC and oxygen. All showed clinical improvement, including SpO2 levels and the number of apneas. Two patients were discharged with nocturnal use of Airvo 2 at home. The median duration of HFNC use was 165 (34 to 445) days. Conclusions: Prolonged use of HFNC is useful in selected pediatric patients, well tolerated, and feasible for home use.

Terapia con cánula nasal de alto flujo en pacientes pediátricos en domicilio / High flow nasal cannula therapy in pediatric patients at home

Se realiza comentario de estudio de Israel en el cual analizan 75 pacientes pediátricos que utilizaron cánula nasal de alto flujo (CNAF) en domicilio, evaluando la seguridad, las indicaciones, los parámetros de utilización, la duración del tratamiento, los resultados clínicos y la satisfacción de los padres. Se acompaña de una revisión de la literatura del tema.

A comment is made on a study conducted in Israel analyzing 75 pediatric patients who used high-flow nasal cannula at home, evaluating safety, indications, utilization parameters, treatment duration, clinical outcomes, and parental satisfaction. It is accompanied by a literature review on the topic.

Impacto de la cánula nasal de alto flujo y la ventilación no invasiva en la fisiología deglutoria: revisión de la literatura / Impact of high-flow nasal cannula and non-invasive ventilation on swallowing physiology: a literature review

El proceso deglutorio requiere de una adecuada coordinación entre respiración y deglución. En el contexto clínico, el uso de dispositivos ventilatorios no invasivos, como la cánula nasal de alto flujo (CNAF) o la ventilación no invasiva (VNI), ha cobrado gran relevancia durante los últimos años. Sin embargo, existe escasa información respecto a la interferencia que estos dispositivos podrían ocasionar en la fisiología deglutoria. En este contexto, y con el objetivo de describir el impacto de la CNAF y la VNI en la fisiología deglutoria, se realizó una revisión de la literatura en PubMed, Medline, Embase, Web of Science, Lilacs y Scielo. Se incorporaron estudios que incluyeran población ≥18 años, con uso de CNAF o VNI. Se excluyeron estudios en población con antecedentes de disfagia, necesidad de intubación, presencia de enfermedad neurológica, neuromuscular o respiratoria, entre otros. Los resultados de los estudios muestran que la CNAF podría disminuir el número de degluciones (en flujos ≥ 20 L/min; p<0,05),disminuir el tiempo medio de activación de la respuesta deglutoria proporcional al flujo empleado (p<0,05), incrementar el riesgo aspirativo en flujos altos (>40 L/min, p<0,05) e incrementar en promedio la duración del cierre del vestíbulo laríngeo (p<0,001). La VNI modo BiPAP, por su parte, podría aumentar el riesgo aspirativo debido al incremento en la tasa de inspiración post deglución (SW-I, p<0,01). Si bien la evidencia disponible es limitada, los resultados aportan información relevante a considerar en el abordaje de usuarios que utilicen estos dispositivos ventilatorios. Futuras investigaciones deberían ser desarrolladas para fortalecer la evidencia presentada.

Deglutition requires adequatecoordination between breathing and swallowing. In the clinical context, the use of non-invasive ventilatory devices such as high-flow nasal cannulas(HFNC) or non-invasive ventilation (NIV) has become highlyrelevantin recent years. However, there is little information regarding howthese devices could interferewith the physiologyof deglutition. This study aimedto describe the impact of HFNC and NIV on swallowing physiology. To this end, aliterature review was carried out usingPubMed, Medline, Embase, Web of Science, Lilacs,and Scielo. Studies performed onpopulations≥18 years old where HFNC or NIV were used were included. Studies where thepopulation hada history of dysphagia, need for intubation, and presentedneurological, neuromuscular,or respiratory diseases, among others, were excluded. The results show that HFNC could decrease the swallowing rate(with flows≥ 20 L/min; p<.05), decrease the mean activation time of the swallowing reflex in proportion to the flow (p<.05), increase the risk of aspiration when usinghigherflows (>40 L/min, p<0.05),and increase the average duration of the laryngeal vestibuleclosure(p<.001).NIV, particularly BiPAP, could increase the risk of aspiration due to the higherrate of post-swallowing inspiration (SW-I, p<.01). Although the evidence available on this matter is limited, theseresults offerrelevant information that should beconsideredwhen working with patients who use these ventilatory devices. Furtherresearch should be carriedoutto strengthen the evidence that is provided in this study.

Análisis de la experiencia del uso de cánula nasal de alto flujo como terapéutica en neumonía por SARS-CoV-2 / Analysis of the experience of the use of high-flow nasal cannula as therapeutics in SARS-CoV-2 pneumonia

RESUMEN Introducción: Durante la pandemia por SARS-CoV-2, la cánula nasal de alto flujo (CNAF) se usó como soporte en espera de Unidad de terapia intensiva (UTI) o como alternativa a la ventilación invasiva. Objetivos: Primario: Determinar si la cánula nasal de alto flujo evita la intubación oro traqueal. Secundarios: Analizar predictores de éxito al inicio de la cánula nasal de alto flujo y análisis descriptivo de la muestra. Materiales y métodos: Estudio observacional descriptivo retrospectivo. Se incluyeron pacientes mayores de 16 años positivos para SARS-CoV-2, atendidos en guardia y unidad de terapia intensiva, que utilizaron cánula nasal de alto flujo entre octubre de 2020 y marzo 2021. Se recolectaron datos en planillas individuales, analizadas por un profesional externo. Resultados: Se incluyeron en el trabajo 72 pacientes (de 16 a 88 años), 20 mujeres y 52 hombres. El 50 % de la muestra evitó la intubación orotraqueal. El IROX inicio grupo "éxito" vs. grupo "fracaso", p = 0,006. Comparación Irox 12 h grupo "éxito" vs. grupo "fracaso" p < 0,001. Comparación "tiempo desde ingreso a inicio de cánula nasal de alto flujo" grupo "éxito" vs. grupo "fracaso", p = 0,133. Comparación "Delta IROX" grupo "éxito" vs grupo "fracaso" p = 0,092. Conclusión: Se evitó la intubación orotraqueal en el 50 % de los casos. El IROX de inicio y el IROX a las 12 h del uso de cánula nasal de alto flujo fue estadísticamente significativo, lo que es un buen predictor del éxito en esta población. La fecha de inicio de síntomas y el uso de cánula nasal de alto flujo y el delta del IROX durante las pri meras 12 h no fue estadísticamente significativo para el éxito de la terapia. Estos datos son una herramienta útil con el objeto de generar protocolos de selección de pacientes para esta patología.

ABSTRACT Introduction: During the SARS-CoV-2 pandemic, the high flow nasal cannula (HFNC) was used as support while waiting for the Intensive Care Unit (ICU) or as an alternative to invasive ventilation. The objective of this work is the description and analysis of the use of CNAF in our population. Objectives: Primary: Determine if HFNC prevents orotracheal intubation. Secondary: Analyze predictors of success at the start of CNAF and a descriptive analysis of the sample Materials and method: Retrospective descriptive observational study. Patients over 16 years of age positive for SARS-CoV-2, treated in Guard and ICU were included. who used CNAF between October 2020 and March 2021 Data was collected in individual forms, analyzed by an external professional. Results: The study included 72 patients (16 to 88 years old), 20 women and 52 men; 50 % of the sample avoided orotracheal intubation. Start IROX, group "success" vs. group "failure" p = 0.006. Comparison Irox.12 h group "success" vs. group "failure" p < 0.001. Comparison "Time from admission to start of CNAF" group "success" vs. group "failure" p = 0.133. Comparison "Delta IROX" group "success" vs. group "failure" p = 0.092. Conclusion: HFNC avoided orotracheal intubation in the 50 % of the cases. The initial IROX and the IROX 12 hours after the use of HFNC were statistically significant, which is a good predictor of success in this population. The date of onset of symptoms and the use of FNAF and IROX delta during the first 12 hours were not statistically significant for the success of the therapy. These data are a useful tool for generating patient selection protocols for this pathology.

Terapia de alto flujo ¿Una alternativa en rehabilitación? / High flow therapy: An option to rehabilitation?

La pandemia por el virus SARS-COV2 que causó la enfermedad COVID-19 ha traído grandes desafíos al sistema de salud tanto a nivel nacional como mundial. En Chile, gracias al esfuerzo de organismos gubernamentales e instituciones privadas, los centros de salud se han equipado con distintos dispositivos de terapia ventilatoria (ventilación mecánica invasiva y no invasiva, y terapia de alto flujo de oxígeno mediante cánula nasal (TAF) con la finalidad de abarcar mayor atención de pacientes tras un periodo de crisis sanitaria que colapsó las redes de atención secundaria y terciaria de salud. En concordancia a esto, es interesante evaluar qué utilidad puede darse a estos equipos posterior a la pandemia, considerando que en varios centros de salud se duplicó o triplicó la disponibilidad de recursos técnicos. En este contexto, la TAF entrega efectos fisiológicos favorables y útiles en escenarios clínicos que implican aumento de las demandas ventilatorias, no sólo en condiciones de insuficiencia respiratoria hipoxémica aguda, sino en condiciones en donde el ejercicio aeróbico es un pilar fundamental, como es el caso de los diferentes programas de rehabilitación (cardiovascular, respiratorio, metabólico, etc.) incluidos como Garantías Explícitas de Salud (GES). Así, la incorporación de TAF en la rehabilitación pulmonar sería una opción adecuada en pacientes con disfunciones respiratorias crónicas, ampliando la cobertura sanitaria que estos programas tienen hoy en día.

The SARS-COV2 pandemic that caused the COVID-19 disease has brought significant challenges to the health system nationally and globally. In Chile, thanks to the efforts of government agencies and private institutions, health centres have been equipped with di-fferent ventilatory therapy devices (invasive and non-invasive mechanical ventilation, and high-flow oxygen therapy by nasal cannula (HFOT)), in order to cover more patient care after a period of a health crisis that collapsed secondary and tertiary health care networks. Accordingly, it is interesting to evaluate concerning what use can be given to these teams after the pandemic, even more considering that the availability of technical resources doubled or tripled in several health centres. In this context, HFOT provides favourable and useful physiological effects in clinical scenarios that involve increased ventilatory demands, not only in conditions of acute hypoxemic respiratory failure but also in conditions where aerobic exercise is a fundamental pillar, as is the case of the different rehabilitation programs (cardiovascular, respiratory, metabolic, etc.) included as Health Guarantees (Garantías Explicitas en Salud, GES). Thus, incorporating HFOT in pulmonary rehabilitation would be an appropriate option in patients with chronic respiratory dysfunctions, expanding the health coverage that these programs have today.

Vacuum-assisted cortex removal - A novel change to the tradition

In developing countries, manual small-incision cataract surgery (MSICS) has surfaced as the cost-effective alternative to phacoemulsification. The Simcoe irrigation-aspiration cannula was developed nearly 40 years ago and is still the most frequently employed tool for cortex aspiration. Although it stands unsurpassed, here we attempt to introduce an addition to the existing Simcoe cannula to achieve a dynamic and controlled vacuum with the added advantage of less physical strain and an effective volume of aspiration. The vacuum-assisted cortex removal device is based on a simple spring action mechanism, where the relaxation of the spring pushes the plunger up and thereby generates a controlled vacuum

Hydroexpression - A novel technique to deliver nucleus in small-incision cataract surgery

Nucleus delivery is still considered as one of the tough steps in SICS among fresh surgeons, leading to various complications at the verge of completion of surgery which further decreases the confidence and elongates the learning curve among the residents,trainees & fellows. Our new technique 揌ydroexpression� utilizes minimal manipulation and minimal instrumentation to express the nucleus with only hydro-cannula without even use of viscoelastics in AC.

Development and Validation of the Intravenous Infiltration and Extravasation Risk Assessment Tool (IIERAT) for Pediatric Patients

Objective: To develop and validate a new tool viz., Intravenous Infiltration and Extravasation Risk Assessment Tool (IIEART) for assessing risk of fluid extravasation in children. Participants: 120 children (aged 2-18 year) undergoing peripheral intravenous cannulation were recruited from four hospitals of Haryana to determine the IIEART scale’s psychometric properties. Methods: The tool was developed under four phases with Modified Delphi rounds among nine experts. After experts’ confirmation of final draft, the reliability and validity of the tool was ascertained. Results: The final IIERAT with 11 items showed good internal consistency (?=0.81) with inter-rater reliability of (?=0.88). To calculate predictive validity, sensitivity and specificity were assessed for 3 consecutive days from the day of cannulation. At a score >21, the sensitivity was 100% and specificity was 100% with area under curve of 1.0 (95% CI 1.0, 1.0) on second day of cannulation. Conclusion: The IIEART developed was found to be valid and reliable and can be used by healthcare personnel to predict pediatric patients at risk for intravenous infiltration and extravasation.

Cánula Nasal de Alto Flujo en Adultos con Enfermedades Respiratorias Crónicas durante el Ejercicio Físico: Protocolo de Revisión Sistemática y Metaanálisis / High-Flow Nasal Cannula in Adults with Chronic Respiratory Diseases during Physical Exercise: A Protocol Systematic Review and Meta-analysis

Introducción. El entrenamiento físico puede mejorar la capacidad de ejercicio, la disnea y la calidad de vida (CV) en pacientes con enfermedades respiratorias crónicas (ERC). En este contexto, el uso de oxígeno suplementario a través de una cánula nasal de alto flujo (CNAF) podría ser un dispositivo que permita tolerar mayores niveles de actividad con menos síntomas de esfuerzo físico, optimizando en última instancia la capacidad de ejercicio y la CV. Objetivo. Este protocolo pretende conducir una revisión sistemática para evaluar el efecto terapéutico de la CNAF durante el ejercicio físico en pacientes con ERC. Fuente de búsqueda. Se realizarán búsquedas en el Registro Cochrane Central de Ensayos Controlados (CENTRAL), PUBMED, Embase, Lilacs, Physiotherapy Evidence Database (PEDro), International Clinical Trials Registry Platform (ICTRP), ClinicalTrials.gov y literatura gris. Criterios de elegibilidad. Examinaremos los ECA de acuerdo con los criterios de elegibilidad para su inclusión en nuestra revisión. Dos revisores examinarán de forma independiente cada estudio para la elegibilidad, la extracción de datos y la evaluación del riesgo de sesgo. Se combinarán los resultados mediante un metanálisis y se aplicará el sistema GRADE para evaluar la certeza de las pruebas para cada resultado. La medida de resultado primaria será la capacidad de ejercicio, y las medidas de resultado secundarias serán la calidad de vida, la disnea, la funcionalidad, la comodidad, las complicaciones y adherencia. Se realizarán metaanálisis para determinar la diferencia de medias (DM) o la DM estandarizada para los datos continuos y la razón de riesgo para los datos dicotómicos. Se realizarán análisis de subgrupos según los tipos y la gravedad de la enfermedad, las condiciones de ejercicio físico y el estado de los dispositivos de oxigenoterapia. Ética y difusión. Como los investigadores no accederán a información que pueda conducir a la identificación de un participante individual, no fue necesario a obtener aprobación ética. Número de registro de PROSPERO: CRD42022336263.

Background. Physical training can improve exercise capacity, dyspnoea, and quality of life (QoL) in patients with chronic respiratory diseases (CRDs). It has been suggested that using supplemental oxygen through a high-flow nasal cannula (HFNC) could lead to higher levels of activity to be tolerated with fewer symptoms of physical exertion, ultimately optimizing exercise capacity and QoL. Objective. To conduct a systematic review to assess the therapeutic effect of HFNC during physical exercise in patients with CRDs. We will search the Cochrane Central Register of Controlled Trials (CENTRAL), PUBMED, Embase, Lilacs, Physiotherapy Evidence Database (PEDro), International Clinical Trials Registry Platform (ICTRP), ClinicalTrials.gov, and grey literature. Eligibility criteria. We will examine RCTs according to the eligibility criteria for inclusion in our review. Two reviewers will independently examine each study for eligibility, data extraction, and risk of bias assessment. We will combine the results using meta-analysis and apply the GRADE system to assess the certainty of the evidence for each outcome. The primary outcome will be exercise capacity, and secondary outcomes will be QoL, dyspnoea, functionality, comfort, complications, and adherence. We will perform meta-analyses to determine the mean difference (MD) or standardized MD for continuous data and the risk ratio for dichotomous data. Subgroup analyses will be performed according to types and severity of disease, physical exercise conditions, and condition of oxygen therapy devices. Ethics and Dissemination. As researchers will not access information that could lead to the identification of an individual participant, obtaining ethical approval was waived. Prospero registration number: CRD42022336263.

Inovação em cânula de lipoaspiração para coleta de enxerto de gordura para uso em reconstrução mamária / Innovation in liposuction cannula to harvest fat graft to use in breast reconstruction

Introdução: A evolução da técnica de lipoaspiração e da enxertia de gordura associada a segurança oncológica permitiram utilizar a gordura como preenchedor autólogo em pacientes com neoplasia de mama que eram submetidas a reconstrução mamária. O objetivo é apresentar uma inovação no instrumento de coleta de gordura que será utilizada como enxerto, para uso em reconstrução mamária. Métodos: Foi realizada a busca de anterioridade nos bancos de dados internacionais e nacional e a confecção de um protótipo de cânula de coleta de gordura de 35cm de comprimento, com diâmetro do tubo de 4mm, com 10 furos redondos na sua extremidade distal com 2mm de diâmetro. Foi realizado um experimento de aspiração de substância viscosa comparando o protótipo com dois modelos de cânulas com desenho padrão da indústria, de três furos tipo Mercedes e de cinco furos tipo Pitanguy. Resultados: Foram encontrados quatro patentes de alta relevância e uma patente de média relevância, que diferem do modelo de utilidade proposto quando se comparam o tipo de desenho da extremidade distal das cânulas estudadas e a função dos instrumentos identificados. Quando comparou-se a eficiência do protótipo, a cânula de cinco furos foi a mais eficiente na aspiração da substância viscosa, e não houve diferença estatística na velocidade de aspiração entre o protótipo e a cânula de três furos tipo Mercedes. Conclusão: A inovação apresentada para a coleta de enxerto de gordura para uso em reconstrução mamária apresentou a mesma eficiência que a cânula Mercedes de três furos neste modelo experimental.

Introduction: The evolution of liposuction and fat graft technique with the oncologic safety allowed to use the fat as autologous filler in patients with breast cancer and submitted to breast reconstruction. The objective is to introduce an innovation in the instrument used to harvest fat grafts for breast reconstruction. Methods: Search of anteriority and trademarks were performed at international and national databases, and a prototype was built as a fat harvest instrument with 35cm in length, 4cm in diameter, with 10 holes at the distal extremity, with 2mm diameter each. It was experimented with a harvest of a viscous substance, comparing the prototype with two regular industry cannulas types: three holes Mercedes' type and five roles Pitanguy's type. Results: Four high-relevance patents and one medium-relevance patent were found, which differ from the proposed utility model when comparing the type of design of the distal end of the studied cannulas and the function of the instruments identified. When the prototype's efficiency was compared with the other cannulas, the cannula with five holes in Pitanguy's type was the most efficient, and it was no statistical difference between the prototype and the cannula with three roles in Mercedes' type. Conclusion: The innovation presented to harvest fat graft for breast reconstruction had the same efficiency in harvesting the viscose substance as the cannula Mercedes type with three holes in this experimental model.