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Objective To investigate the effects of dynamic lung compliance(Cdyn)-guided indi-vidual positive end-expiratory pressure(PEEP)titration on pulmonary function in elderly patients undergoing laparoscopic colorectal cancer surgery.Methods Sixty-eight elderly patients were selected for laparoscopic radical resection of colorectal cancer,37 males and 31 females,aged 65-79 years,BMI<30 kg/m2,ASA physical status Ⅱ or Ⅲ.The patients were divided into two groups using the random number table method:individualized PEEP group(group P)and control group(group C),34 patients in each group.In group P,the patients received recruitment maneuvers and PEEP titration test at immediately after intubation,immediately after establishing pneumoperitoneum-Trendelenburg position and immediately after pneumoperitoneum.The patients in group C received PEEP 5 cmH2 O during procedure.The three best titra-tion PEEP and the actual tidal volume(VT)in group P were also recorded.PaO2,PaCO2,PETCO2 10 mi-nutes after the tracheal intubation(T1),10 minutes(T2)and 1 hour(T3)after establishing pneumoperito-neum-Trendelenburg position,at the end of the surgery but before extubation(T4)were recorded,and the oxygenation index(OI),physiological dead space to tidal volume(Vd/VT),alveolar arterial oxygen differ-ence(A-aDO2),driving pressure,and Cdyn were calculated.Concentrations of interleukin-8(IL-8),tumor necrosis factor-α(TNF-α),Clara cell secretoyr protein(CC16)and lung alveolar surface active sub-stances-D(SP-D)in the serum samples were determined by ELISA before anesthesia induction(T0)and 10 minutes after extubation(T5).Postoperative pulmonary complications(PPCs)were also recordrd.Results The individualized PEEP of Cdyn?guided PEEP titration was 4 cmH2O. Compared with group C, the PaO2 and OI in group C were significantly increased at T4, the Cdyn was significantly increased at T1,T3, and T4, the driving pressure was significantly decreased at T1 -T4, the serum concentration of CC16 was significantly decreased at T5 ( P < 0. 05). There were no significant differences in PaCO2, PET CO2,A?aDO2, and Vd/ VT between the two groups. There was no severe PPCs in the two groups. Conclusion Pressure?controlled ventilation modes combined with Cdyn?guide PEEP titration can increase the Cdyn, reduce thedriving pressure, and improve OI at the end of the operation, reduce the concentrations of CC16 at postop?eration, improve pulmonary function in elderly patients undergoing laparoscopic colorectal cancer surgery.
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Appropriate positive end-expiratory pressure(PEEP)level is an important component of protective lung ventilation strategy.PEEP can maintain the openness of alveoli and reduce lung collapse in-jury.Although individualized PEEP application has been increasingly recognized by clinical physicians,the optimal PEEP titration method is still controversial.Electrical impedance tomography(EIT)is a non-inva-sive and radiation-free imaging technique that can be used to dynamically assess lung function at the bedside.EIT presents changes in impedance during ventilation as dynamic images,which can reflect altera-tions in ventilation and gas distribution before and after PEEP adjustments.Therefore,EIT can be utilized to tailor individualized PEEP.This article provides a brief overview of the basic principles and monitoring pa-rameters of EIT.It elucidates the PEEP titration method under the guidance of EIT in clinical applications(PEEPEIT),aiming at enhancing the understanding of the advantages and limitations of EIT and providing reference for the setting of individualized PEEP.
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Objective To explore the effect of protective ventilation strategies based on individualized positive end expiratory pressure(PEEP)regulated by driving pressure(Pd)in infants under OLV.Methods Sixty infants undergoing elective thoracoscopic surgery were randomly divided into the control group and driving pressure group,with 30 cases in each group.The two groups were compared in terms of MAP,HR,tidal volume(Vt),PEEP,Pd,airway peak pressure(Ppeak),and static lung compliance(Cs),and arterial blood gas during OLV before the artificial pneumothorax(T0),10 min(T1),30 min(T2),and 60 min(T3)after the artificial pneumothorax,and right at the end of the artificial pneumothorax(T4).Results There were no significant differences in MAP,HR,and Vt between the two groups at all the time points(P＞0.05).Both groups showed the increase in Pd and Ppeak and decresase in Cs at T1,T2,and T3(all P＜0.05).PaO2 and OI in both group were decreased and PaCO2 was increased at T2(all P＜0.05).Compared with the control group,the driving pressure group presented lower Pd and Ppeak,higher PEEP and Cs at T1,T2,and T3(P＜0.05),and higher PaO2 and OI(P＜0.05)and no significant differences in PaCO2 and FiO2 at T2(P＜0.05).The rate of rescue ventilation during OLV was lower in the driving pressure group(2 cases)than in the control group(9 cases)(6.9%versus 32.4%,P＜0.05).There was no significant difference in the inci-dence of postoperative complications between the two groups(P＜0.05).Conclusion The individualized positive end expiratory pressure(PEEP)regulated by Pd can optimize the PEEP settings upon infant individuals under OLV and improve the compliance and oxygenation of ventilated lung.
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Objective To evaluate the effect of driving pressure(DP)-guided individualized positive end-expiratory pressure(PEEP)combined with regular lung recruitment maneuvers(RMs)on atelectasis in elderly patients undergoing laparoscopic surgery in the Trendelenburg position using lung ultrasound.Methods A total of 62 patients aged 65-85 years old and classified by ASA status Ⅰ-Ⅲ undergoing laparoscopic radical resection of colorectal cancer were included and randomly divided into the experimental group(n=31)and the control group(n=31).Both groups received one RM after the beginning of pneumoperitoneum,followed immediately by titration of individualized PEEP with the lowest DP,and both groups received another RM after the end of pneumoperitoneum.The experimental group received additional RM every 30 min from the beginning of pneumoperitoneum,while the control group received no intervention.Recording time points for observation were:before induction of anesthesia(T0),30 min after pneumoperitoneum(T1),90 min after pneumoperitoneum(T2),at the end of surgery(T3)and 45 min after entering the postanesthesia care unit(PACU,T4).Lung ultrasound score(LUS)was recorded at T0,T3 and T4.Dynamic lung compliance(Cdyn)was recorded at T1-T3.Oxygenation index(OI),mean arterial pressure(MAP)and heart rate(HR)were recorded at T0-T4.Hypotension during RM,hypoxic saturation events in PACU and the incidence of pulmonary complications(POPC)within the first 7 days after surgery were recorded.Results Compared with the control group,LUSs at T3 and T4 were significantly decreased in the experimental group(P<0.05),and OI and Cdyn at T2 and T3 were significantly increased(P<0.05).In addition,the incidence of hypoxia saturation events in PACU was lower in the experimental group than that in the control group(P<0.05).There were no significant differences in the incidence of hypotension during lung recruitment and the incidence of POPC within 7 days after surgery between the two groups.Conclusion The individualized PEEP combined with regular RMs can effectively reduce the atelectasis observed by lung ultrasound immediately after laparoscopic radical resection of colorectal cancer and in PACU in elderly patients.
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@#Objective To evaluate the correlation between positive end-expiratory pressure (PEEP) level and postoperative pulmonary complications (PPCs) in patients undergoing thoracoscopic lung surgery. Methods The clinical data of patients who underwent elective thoracoscopic lung surgery at West China Hospital of Sichuan University from January 2022 to June 2023 were retrospectively analyzed. Patients were divided into 2 groups according to intraoperative PEEP levels: a PEEP 5 cm H2O group and a PEEP 10 cm H2O group. The incidence of PPCs in the two groups after matching was compared using a nearest neighbor matching method with a ratio of 1∶1, setting the clamp value as 0.02. Results A total of 538 patients were screened, and after propensity score-matching, a total of 229 pairs (458 patients) were matched, with an average age of 53.9 years and 69.4% (318/458) females. A total of 118 (25.8%) patients had PPCs during hospitalization after surgery, including 60 (26.2%) patients in the PEEP 5 cm H2O group and 58 (25.3%) patients in the PEEP 10 cm H2O group, with no statistically significant difference between the two groups [OR=0.997, 95%CI (0.495, 1.926), P=0.915]. Multivariate logistic regression analysis showed that PEEP was not an independent risk factor for PPCs [OR=0.920, 95%CI (0.587, 1.441), P=0.715]. Conclusion For patients undergoing thoracoscopic lung surgery, intraoperative PEEP (5 cm H2O or 10 cm H2O) is not associated with the risk of PPCs during hospitalization after surgery, which needs to be further verified by prospective, large-sample randomized controlled studies.
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ObjectiveTo compare the effects of different tidal volumes and positive end expiratory pressures （PEEPs） during mechanical ventilation on the cardiac output of pigs measured by pulmonary artery catheter， transpulmonary thermodilution and pulse contour analysis， and to explore their consistency in cardiac output determination. MethodsTwelve experimental pigs were selected and randomly divided into 3 groups， with 4 pigs in each. Cardiac output was measured by different methods， control group by pulmonary artery catheter， group A by transpulmonary thermodilution and group B by pulse contour analysis. Then we compared the effects of different tidal volumes and PEEPs on the cardiac output of pigs and to explore the consistency. The correlation coefficient between pulse contour analysis and pulmonary artery catheter was r=0.754， and they were positively correlated. The correlation coefficient between transpulmonary thermodilution and pulmonary artery catheter was r=0.771， and they were positively correlated. In determining cardiac output， pulse contour analysis was consistent with pulmonary artery catheter， with a relative error of 13.5% between them； transpulmonary thermodilution was consistent with pulmonary artery catheter， with a relative error of 12.9% between them. The cardiac output decreased significantly along with the increase of tidal volumes or PEEPs and the differences were statistically significant （P<0.05） ConclusionPulmonary artery catheter， transpulmonary thermodilution and pulse contour analysis are well consistent with each other in measuring the cardiac output of pigs. The pigs’cardiac output gradually decreased along with the increase of tidal volumes or PEEPs during mechanical ventilation.
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Objective:To explore a simple method for measuring the dynamic intrinsic positive end-expiratory pressure (PEEPi) during invasive mechanical ventilation.Methods:A 60-year-old male patient was admitted to the critical care medicine department of Dongying People's Hospital in September 2020. He underwent invasive mechanical ventilation treatment for respiratory failure due to head and chest trauma, and incomplete expiratory flow occurred during the treatment. The expiratory flow-time curve of this patient was served as the research object. The expiratory flow-time curve of the patient was observed, the start time of exhalation was taken as T 0, the time before the initiation of inspiratory action (inspiratory force) was taken as T 1, and the time when expiratory flow was reduced to zero by inspiratory drive (inspiratory force continued) was taken as T 2. Taking T 1 as the starting point, the follow-up tracing line was drawn according to the evolution trending of the natural expiratory curve before the T 1 point, until the expiratory flow reached to 0, which was called T 3 point. According to the time phase, the intrapulmonary pressure at the time just from expiratory to inspiratory (T 1 point) was called PEEPi 1. When the expiratory flow was reduced to 0 (T 2 point), the intrapulmonary pressure with the inhaling power being removed hypothetically was called PEEPi 2. And it was equal to positive end-expiratory pressure (PEEP) set in the ventilator at T 3 point. The area under the expiratory flow-time curve (expiratory volume) between T 0 and T 1 was called S 1. And it was S 2 between T 0 and T 2, S 3 between T 0 and T 3. After sedation, in the volume controlled ventilation mode, approximately one-third of the tidal volume was selected, and the static compliance of patient's respiratory system called "C" was measured using the inspiratory pause method. PEEPi 1 and PEEP 2 were calculated according to the formula "C =ΔV/ΔP". Here, ΔV was the change in alveolar volume during a certain period of time, and ΔP represented the change in intrapulmonary pressure during the same time period. This estimation method had obtained a National Invention Patent of China (ZL 2020 1 0391736.1). Results:① PEEPi 1: according to the formula "C =ΔV/ΔP", the expiratory volume span from T 1 to T 3 was "S 3-S 1", and the intrapulmonary pressure decreased span was "PEEPi 1-PEEP". So, C = (S 3-S 1)/(PEEPi 1-PEEP), PEEPi 1 = PEEP+(S 3-S 1)/C. ②PEEPi 2: the expiratory volume span from T 2 to T 3 was "S 3-S 2", and the intrapulmonary pressure decreased span was "PEEPi 2-PEEP". So, C = (S 3-S 2)/(PEEPi 2-PEEP), PEEPi 2 = PEEP+(S 3-S 2)/C. Conclusion:For patients with incomplete expiratory during invasive mechanical ventilation, the expiratory flow-time curve extension method can theoretically be used to estimate the dynamic PEEPi in real time.
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@#Objective To explore the efficacy and safety of lung recruitment maneuver(LRM)on postoperative hypoxemia in patients with acute type A aortic dissection(ATAAD).Methods A total of 56 ATAAD patients with postoperative hypoxemia in the First Affiliated Hospital of Guangxi Medical University from November 2019 to May 2022 were selected and randomly divided into LRM group(n=36)and conventional treatment group(n=20).Patients in conventional treatment group received routine mechanical ventilation on the basis of lung protective ventilation.The patients in LRM group were treated with incremental positive end expiratory pressure(PEEP).Arterial blood gas analysis,respiratory parameters,hemodynamics parameters and serum interleukin(IL)-6 and IL-10 levels were compared between two groups before and after treatment.Results At 12h and 24h after treatment,arterial partial pressure of oxygen(PaO2),oxygenation index(OI),static compliance(Cstat)and dynamic compliance(Cdyn)in two groups were significantly higher than before treatment,the alveolar-arterial gradient of oxygen[PO2(A-a)],respiratory index(RI),peak inspiratory pressure(Ppeak)and plateau pressure(Pplat)were significantly lower than before treatment(P<0.05).PaO2,OI,Cstat and Cdyn in LRM group were significantly higher than those in conventional treatment group,PO2(A-a),RI,Ppeak and Pplat were significantly lower than those in conventional treatment group(P<0.05).Systolic blood pressure and mean arterial pressure decreased and central venous pressure increased during pulmonary reexpansion in LRM group(P<0.05),and all patients returned to baseline level after pulmonary reexpansion.At 12h after treatment,serum IL-6 and IL-10 levels in both groups were significantly lower than before treatment(P<0.05).Conclusion Incremental PEEP can improve oxygenation and lung compliance in patients with hypoxemia after ATAAD surgery,but it has transient effects on hemodynamics,and should be closely monitored during treatment.
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Abstract Background: Positive end-expiratory pressure (PEEP) can overcome respiratory changes that occur during pneumoperitoneum application in laparoscopic procedures, but it can also increase intracranial pressure. We investigated PEEP vs. no PEEP application on ultrasound measurement of optic nerve sheath diameter (indirect measure of increased intracranial pressure) in laparoscopic cholecystectomy. Methods: Eighty ASA I-II patients aged between 18 and 60 years scheduled for elective laparoscopic cholecystectomy were included. The study was registered in the Australian New Zealand Clinical Trials (ACTRN12618000771257). Patients were randomly divided into either Group C (control, PEEP not applied), or Group P (PEEP applied at 10 cmH20). Optic nerve sheath diameter, hemodynamic, and respiratory parameters were recorded at six different time points. Ocular ultrasonography was used to measure optic nerve sheath diameter. Results: Peak pressure (PPeak) values were significantly higher in Group P after application of PEEP (p = 0.012). Mean respiratory rate was higher in Group C at all time points after application of pneumoperitoneum (p < 0.05). The mean values of optic nerve sheath diameters measured at all time points were similar between the groups (p > 0.05). The pulmonary dynamic compliance value was significantly higher in group P as long as PEEP was applied (p = 0.001). Conclusions: During laparoscopic cholecystectomy, application of 10 cmH2O PEEP did not induce a significant change in optic nerve sheath diameter (indirect indicator of intracranial pressure) compared to no PEEP application. It would appear that PEEP can be used safely to correct
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Humans , Adolescent , Adult , Middle Aged , Young Adult , Pneumoperitoneum , Cholecystectomy, Laparoscopic , Optic Nerve/diagnostic imaging , Australia , Intracranial Pressure , Positive-Pressure Respiration/methodsABSTRACT
Objective:To evaluate the effect of individualized positive end-expiratory pressure (PEEP) ventilation strategy guided by driving pressure on intraoperative intracranial pressure in patients with moderate traumatic brain injury (TBI).Methods:Total of 111 patients aged 18-65 years old, with BMI of 17-28 kg/m 2, ASA grade of Ⅲ-Ⅳ, and Glasgow coma score of 9-11 before operation were treated with evacuation of intracranial hematoma in emergency. The patients were randomly divided into 0 cmH 2O PEEP group (Group 0 PEEP), 5 cmH 2O PEEP group (Group 5 PEEP) and individualized PEEP ventilation group (Group P) guided by driving pressure. The volume control ventilation mode is adopted, VT is 6 mL/kg, FiO 2 is 60%, and the inspiratory expiratory ratio is 1:2. Patients in Group 0 PEEP and Group 5 PEEP were given PEEP 0 or 5 cmH 2O for ventilation after tracheal intubation until the end of the operation. Patients in Group P were given individualized PEEP titration ventilation strategy guided by driving pressure after intubation. Blood gas analysis was performed at 5 min (T1) after tracheal intubation, 60 min (T3) after operation, and 5 min (T4) after operation. PaO 2, PaCO 2, and dynamic compliance (Cdyn) were recorded. The optic nerve sheath diameter (ONSD) was measured before anesthesia induction (T0), after PEEP titration in group P (T2, 10 min after ventilation in group 0 PEEP and 5 PEEP) and at T4; Serum neuron specific enolase (NSE) concentration was measured by ELISA before and 1 day and 3 days after operation; The occurrence of nervous system complications (intracranial infection, intracranial hypertension, epilepsy, brain edema, etc.) within 30 days after operation was followed up. Results:Compared with group 0 PEEP and 5 PEEP, Cdyn and PaO 2 in group P increased at T3-4 ( P<0.05), ONSD was not significantly different among the three groups ( P>0.05), NSE in group P decreased significantly at 1 and 3 days after operation, and the incidence of neurological complications in the three groups was not significantly different at 30 days after operation ( P>0.05). Conclusions:Individualized PEEP ventilation strategy guided by driving pressure can help improve lung and brain function in TBI patients.
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La Injuria Pulmonar Autoinducida por el Paciente (p-SILI) es una entidad recientemente reconocida. Clásicamente, el daño producido por la ventilación mecánica (VM) se asoció al uso de presión positiva, y para disminuirlo se crearon distintas estrategias conocidas como parámetros de protección pulmonar. Sin embargo, es importante reconocer los potenciales efectos deletéreos de la ventilación espontánea dependientes de la injuria pulmonar previa que sufra el paciente y del esfuerzo que realice. En este artículo se explican los distintos mecanismos que pueden producir p-SILI y las estrategias descritas en la literatura para prevenirla (AU)
Patient self-inflicted lung injury (p-SILI) is a recently recognized disorder. Classically, damage produced by mechanical ventilation (MV) was associated with the use of positive pressure, and different strategies known as lung protection parameters were created to reduce it. Nevertheless, it is important to recognize the potential deleterious effects of the effort made during spontaneous breathing due to previous lung injury suffered by the patient. This article explains the different mechanisms that may produce p-SILI and the prevention strategies described in the literature. (AU)
Subject(s)
Respiration, Artificial/methods , Respiratory Distress Syndrome, Newborn , Intensive Care Units, Pediatric , Tidal Volume , Positive-Pressure Respiration/methods , Lung Injury/physiopathology , Lung Injury/prevention & controlABSTRACT
Resumen: Introducción: Desde diciembre de 2019, cuando el coronavirus respiratorio tipo 2 y el síndrome de insuficiencia respiratoria agudo (SDRA) por coronavirus tipo 2 (enfermedad por coronavirus 2019 [COVID-19]), se desarrolló en Wuhan, China, se ha convertido en una pandemia mundial, con 105'333.798 casos reportados el 04 de febrero de 2021. El 27 de febrero de 2020, la Ciudad de México reportó el primer caso de COVID-19, seguido de un crecimiento masivo de infecciones en todo el país. El número total de casos hasta hoy es de 1,886.245 con 81,223 casos activos estimados. El 18.77% de los pacientes han requerido hospitalización. El número total de muertes es de 164.290, con una estimación de 184.125. La lesión renal aguda (LRA) se encontró en 28% de los pacientes hospitalizados y en 46% de los pacientes en estado crítico, contribuyendo a una mortalidad significativamente mayor. La identificación de los factores de riesgo es importante para orientar la toma de decisiones tempranas en la clasificación de los pacientes para una monitorización más intensiva y prevenir el aumento de la mortalidad. Objetivo: Analizar el nivel de presión positiva al final de la espiración (PEEP) y factores inflamatorios que intervienen en el desarrollo de LRA e inicio de terapia de reemplazo renal (TRR) en pacientes con COVID-19. Material y métodos: Se realizó un estudio observacional, transversal y retrolectivo en pacientes con ventilación mecánica con SARS-CoV-2 que presentaron LRA y necesidad de TRR ingresados en la Unidad de Cuidados Intensivos Respiratorios del Centro Médico ABC. Se realizó análisis estadístico de medidas de tendencia central, descriptivo; para la identificación de la variable con mayor impacto para el desarrollo de LRA y terapia dialítica se realizó factor predictivo positivo, prueba Pearson para correlacionar con terapia de reemplazo renal. El estudio se aprobó por el Comité de Ética del Centro Médico ABC, Ciudad de México (Folio: ABC TAEABC-22-117). Resultados: Se analizaron en total 210 pacientes con ventilación mecánica con SARS-CoV-2 en la Unidad de Cuidados Intensivos Respiratorios del Centro Médico ABC, de los cuales, 51 (24.17%) desarrollaron LRA y 21 requirieron TRR. Se realizó una curva ROC para predecir el factor con mayor riesgo para presentar LRA, encontrando diferencias significativas en IL-6 con un área bajo la curva ROC de 0.909 (CI: 0.86-0.95). También se encontró significancia estadística en LRA a partir de PEEP por arriba de 13 cmH2O y terapia de reemplazo renal con PEEP > 15 cmH2O. Conclusión: Se encontró una correlación de niveles altos de PEEP y lesión renal aguda. Los marcadores inflamatorios al ingreso del paciente (específicamente IL-6) son parámetros adecuados para guiar el tratamiento; sin embargo, también son de utilidad para orientar a un pronóstico.
Abstract: Introduction: Since December 2019, when respiratory coronavirus type 2 and acute respiratory failure syndrome (ARDS) due to coronavirus type 2 (coronavirus disease 2019 [COVID-19]), developed in Wuhan, China, it has become a global pandemic, with 105,333,798 cases reported on February 4, 2021. On February 27, 2020, Mexico City reported the first case of COVID-19, followed by a massive growth of infections across the country. The total number of cases today is 1,886,245 with 81,223 estimated active cases. 18.77% of patients have required hospitalization. The total number of deaths is 164,290 with an estimated 184,125. AKI was found in 28% of hospitalized patients and 46% of critically ill patients, contributing to significantly higher mortality. Identification of risk factors is important to guide early decision making in triaging patients for more intensive monitoring and prevent increased mortality. Objective: To analyze the level of PEEP and inflammatory factors involved in the development of AKI and onset of RRT in patients with COVID-19. Material and methods: An observational, cross-sectional and retrolective study was performed in mechanically ventilated patients with SARS-CoV-2 who presented AKI and need for RRT admitted to the respiratory intensive care unit of the ABC Medical Center. Statistical analysis of measures of central tendency, descriptive; for the identification of the variable with the greatest impact for the development of AKI and dialytic therapy, a positive predictive factor was performed, Pearson test to correlate with renal replacement therapy. The study was approved by the ethics committee of the ABC Medical Center, Mexico City (Number: ABC TAEABC-22-117). Results: A total of 210 mechanically ventilated patients with SARS-CoV-2 in the Respiratory Intensive Care Unit of the ABC Medical Center were analyzed, of whom 51 patients (24.17%) developed AKI and 21 patients required RRT. An ROC curve was performed to predict the factor with the highest risk of developing AKI, finding significant differences in IL-6 with an area under the ROC curve of 0.909 (CI: 0.86-0.95). Statistical significance was found in AKI with PEEP above 13cmH2O and renal replacement therapy with PEEP > 15cmH2O. Conclusion: A correlation was found between high PEEP levels and acute kidney injury. Inflammatory markers at patient admission (specifically IL-6) are adequate parameters to guide treatment; however, they are also useful to guide prognosis.
Resumo: Introdução: Desde dezembro de 2019, quando o coronavírus respiratório tipo 2 e a síndrome do desconforto respiratório agudo do coronavírus (SDRA) (doença de coronavírus 2019 [COVID-19]), desenvolvida em Wuhan, China, tornou-se uma pandemia em todo o mundo, com 105'333.798 casos relatados em fevereiro 4, 2021. Em 27 de fevereiro de 2020, a Cidade do México relatou o primeiro caso de COVID-19, seguido por um crescimento maciço de infecções em todo o país. O número total de casos até o momento é de 1,886.245, com uma estimativa de 81,223 casos ativos. 18.77% dos pacientes necessitaram de internação. O número total de óbitos é de 164.290, com estimativa de 184.125. A LRA foi encontrada em 28% dos pacientes hospitalizados e 46% dos pacientes críticos, contribuindo para uma mortalidade significativamente maior. A identificação dos fatores de risco é importante para orientar a tomada de decisão precoce na classificação dos pacientes para monitoramento mais intensivo e para evitar o aumento da mortalidade. Objetivo: Analisar o nível de PEEP e fatores inflamatórios envolvidos no desenvolvimento de LRA e início de TRS em pacientes com COVID-19. Material e métodos: Realizou-se um estudo observacional, transversal e retroletivo em pacientes ventilados mecanicamente com SARS-CoV-2 que apresentavam LRA e necessidade de TRS internados na unidade de terapia intensiva respiratória do Centro Médico ABC. Foi realizado análise estatística de medidas de tendência central, descritiva; para identificar a variável de maior impacto no desenvolvimento de LRA e terapia dialítica, realizou-se fator preditivo positivo, o teste de Pearson para correlacionar com a terapia renal substitutiva. O estudo foi aprovado pelo comitê de ética do Centro Médico ABC, Cidade do México (Folio: ABC TAEABC-22-117). Resultados: Foram analisados um total de 210 pacientes com ventilação mecânica com SARS-CoV-2 na unidade de terapia intensiva respiratória do Centro Médico ABC, dos quais 51 pacientes (24.17%) desenvolveram LRA e 21 pacientes requereram TRS. Realizou-se uma curvatura ROC para prever o fator com maior risco para apresentar LRA encontrando diferenças significativas em IL-6 com uma área sob a curvatura ROC de 0.909(CI: 0.86-0.95). Da mesma forma, foi encontrada significância estatística na LRA por PEEP acima de 13 cmH2O e terapia renal substitutiva com PEEP > 15 cmH2O. Conclusão: Encontrou-se uma correlação entre níveis elevados de PEEP e lesão renal aguda. Marcadores inflamatórios na admissão do paciente (especificamente IL-6) são parâmetros adequados para orientar o tratamento; no entanto, eles também são úteis para orientar uma previsão.
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Objective:To evaluate the effects of neuromuscular blocking agents (NMBA) on oxygenation and respiratory conditions in patients with acute respiratory distress syndrome(ARDS).Methods:English databases such as MEDLINE, Embase and Web of Science were searched online, as well as Chinese databases such as China National Knowledge Infrastructure (CNKI), Chinese Biomedical Literature Database and Wanfang Database. Randomized controlled trials (RCTs) of NMBA therapy for ARDS with publication date up to May 2020 were retrieved. Literature was screened according to inclusion and exclusion criteria, and the main analysis indicators were oxygenation index.Results:A total of 5 RCTs were included, and 1 462 ARDS patients were enrolled. Compared with the control group, the ratio of partial arterial oxygen pressure to fraction of inspired (PaO 2)/(FiO 2) significantly improved in the intervention group after 72 hours MD=14.39, (95 %CI 6.40-22.38, P=0.000 4) and 96 hours of NMBA, but there was no difference between PaO 2/FiO 2 at 24 and 48 hours ( P>0.05).Positive end expiratory pressure (PEEP) significantly decreased at 72 hours ( MD=-0.45, 95 %CI -0.87--0.03, P=0.04) and 96 hours ( MD=-0.82, 95 %CI -1.39--0.26, P=0.004) treatment with NMBA, while there was no significant difference in PEEP between 24 and 48 hours after treatment ( P>0.05). At 96 h, plateau pressure (Pplat) in the intervention group was significantly lower ( MD=-1.69, 95 %CI -2.64--0.75, P=0.000 4), and there was no significant difference in Pplat between 24, 48 and 72 h after treatment ( P>0.05). Conclusion:The early use of NMBA within 48 hours has a delayed improvement effect on oxygenation and ventilator conditions in ARDS patients.
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Objective:To evaluate the effect of positive end-expiratory pressure (PEEP) ventilation on cardiac function in patients with early left ventricular (LV) diastolic dysfunction undergoing laparoscopic radical gastrectomy.Methods:Patients who underwent laparoscopic radical gastrectomy under elective general anesthesia from July 2021 to February 2022 at the Subei People's Hospital were enrolled [age 60-75 years old, American Society of Anesthesiologists (ASA) grade Ⅰ-Ⅱ, and left ventricular ejection fraction (LVEF) > 0.50]. Transthoracic echocardiography (TTE) was performed before operation, and the peak early diastolic velocity (E peak) and peak late diastolic velocity (A peak) at the mitral ostium were recorded and the E/A and E peak deceleration time (DT) were calculated. Then isovolumic relaxation time (IVRT) and early peak mitral annular diastolic velocity (e') were recorded and left ventricular E/e' (LVE/e') was calculated. According to the E/A, mitral e', LVE/e', DT, and IVRT, the patients were divided into early LV diastolic dysfunction group (E/A < 1, mitral e' < 7 cm/s, LVE/e' > 14, DT > 200 ms, and IVRT > 100 ms) and normal cardiac function group (1 < E/A < 2, 160 ms < DT < 240 ms, and 70 ms < IVRT < 90 ms), with 35 patients in each group. Both groups were received fixed 5 cmH 2O (1 cmH 2O≈0.098 kPa) PEEP 5 minutes after the beginning of the pneumoperitoneum until the end of the procedure. A volume controlled ventilation was used with a tidal volume (VT) of 7 ml/kg, an inspired oxygen concentration of 0.60, and an inspiratory to expiratory ratio of 1∶2. Left and right myocardial systolic and diastolic function related parameters, including LVEF, LV global longitudinal strain (LVGLS), tricuspid annulus plane systolic migration (TAPSE), the peak early diastolic velocity (E peak) at the mitral and tricuspid valve ostia and the peak early diastolic velocity (e') at the corresponding annulus were measured by transesophageal echocardiography (TEE) before tracheal intubation (T 0), 5 minutes after the pneumoperitoneum (T 1), 5 minutes after PEEP ventilation (T 2), 30 minutes after PEEP ventilation (T 3), and 5 minutes after the end of pneumoperitoneum (T 4), respectively. The left and right ventricular myocardial performance index (LVMPI/RVMPI) was calculated. Results:Finally, 60 patients were included in the analysis, including 28 patients in the early LV diastolic dysfunction group and 32 patients in the normal cardiac function group. Compared with those at T 0, mean arterial pressure (MAP), LVEF, mitral e', LVGLS, tricuspid e' and TAPSE were significantly lower in the normal cardiac function group at T 1, and the early LV diastolic dysfunction group at T 1, T 2, and T 3, and LVMPI, LVE/e', RVE/e', and RVMPI were significantly higher. At T 4, the LVE/e' and the RVE/e' were significantly higher in the early LV diastolic dysfunction group than those at T 0 (LVE/e': 16.52±1.26 vs. 14.32±1.09, and RVE/e': 18.71±1.74 vs. 16.51±1.93, respectively, both P < 0.05), Mitral e' and tricuspid e' were significantly lower than those at T 0 [mitral e' (m/s): 0.07±0.01 vs. 0.09±0.01, tricuspid e' (m/s): 0.06±0.01 vs. 0.08±0.01, both P < 0.05]. Compared with the normal cardiac function group, MAP, LVEF, mitral e', LVGLS, tricuspid e', and TAPSE at T 1, T 2, and T 3 were significantly lower in the early LV diastolic dysfunction group, while LVMPI, LVE/e', RVE/e', and RVMPI were significantly higher. At T 4, the LVE/e' and the RVE/e' were significantly higher in the early LV diastolic dysfunction group than those in the normal cardiac function group (LVE/e': 16.52±1.26 vs. 9.87±1.25, RVE/e': 18.71±1.74 vs. 10.97±1.70, both P < 0.05). Mitral e' and tricuspid e' were significantly lower in the normal cardiac function group [mitral e' (m/s): 0.07±0.01 vs. 0.11±0.02, tricuspid e' (m/s): 0.06±0.01 vs. 0.10±0.02, both P < 0.05]. Conclusions:In early LV diastolic dysfunction patients, compared with patients with normal cardiac function, 5 cmH 2O PEEP can further exacerbate left and right myocardial systolic and diastolic function in patients during pneumoperitoneum; when the pneumoperitoneum was ended, 5 cmH 2O PEEP only worsen left and right myocardial diastolic function in patients, and did not affect left and right myocardial systolic function.
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Resumen: Introducción: el uso de presión positiva al final de la espiración mejora la oxigenación y recluta alvéolos, aunque también provoca alteraciones hemodinámicas e incrementa la presión intracraneal. Material y métodos: se realizó un estudio preexperimental de un solo grupo en pacientes pediátricos aquejados de traumatismo craneoencefálico grave, con hipoxemia asociada, tratados con diferentes niveles de presión positiva al final de la espiración, a los que se les monitorizó la presión intracraneal y la presión de perfusión cerebral para evaluar el efecto de esta maniobra ventilatoria en las variables intracraneales. Resultados: predominaron las edades entre cinco y 17 años, 14 (73.68%) y la escala de coma de Glasgow al ingreso de ocho a nueve puntos (47.36%). La presión intracraneal aumenta cuando la presión positiva al final de la espiración supera los 12 cmH2O. La escala de coma de Glasgow al ingreso de ocho puntos se asoció con secuelas ligeras o ausencia de secuelas (47.36%), todos los niños con tres puntos fallecieron. Conclusiones: el empleo de presión positiva al final de la espiración en el traumatismo craneoencefálico grave requiere de monitorización continua de la presión intracraneal. Corregir la hipertensión intracraneal y la inestabilidad hemodinámica son condiciones necesarias previas al tratamiento.
Abstract: Introduction: the use of positive end expiratory pressure improves oxygenation and recruits pulmonary alveoli, however at the same time it leads to hemodynamic changes and increase intracranial pressure. Material and methods: a prospective descriptive study was done with pediatric patients afflicted with severe traumatic brain injury associated with hypoxemia and treated with different levels of positive end expiratory pressure, to whom the intracranial pressure and cerebral perfusion pressure were monitored so as to evaluate the effect of this ventilation maneuver over the intracranial variables. Results: patients with age between 5-17 years old as well as male sex, 14 (73.68%) were predominant. 9 (47.36%) showed Glasgow coma scale of 8 points on admission. Intracranial pressure starts to rise when the positive end expiratory pressure exceeds 12 cmH2O. Glasgow coma scale with 8 points was associated with mild disability or no disability (47.36%). All the patients that scored 3 points died. Conclusions: the use of positive end expiratory pressure to correct hypoxemia was an applicable therapeutic alternative as long as continuous intracranial pressure monitoring was available in a systematic and personalized way. The correction of intracranial hypertension and hemodynamic instability were a necessary condition before using the ventilatory maneuver in these patients.
Resumo: Introdução: o uso de pressão positiva no final da expiração melhora a oxigenação e recruta alvéolos, embora também cause alterações hemodinâmicas e aumente a pressão intracraniana. Material e métodos: realizou-se um estudo pré-experimental de um único grupo em pacientes pediátricos vítimas de traumatismo cranioencefálico grave, com hipoxemia associada, tratados com diferentes níveis de pressão positiva ao final da expiração, nos quais foram monitoradas a pressão intracraniana e a pressão de perfusão cerebral, para avaliar o efeito desta manobra ventilatória em variáveis intracranianas. Resultados: predominou a faixa etária entre 5-17 anos, 14 (73.68%) e a escala de coma de Glasgow na admissão de 8 pontos, 9 (47.36%). A pressão intracraniana aumenta quando a pressão positiva no final da expiração excede 12 cmH2O. A escala de coma de Glasgow na admissão de 8 pontos foi associada a sequelas leves ou sem sequelas (47.36%), todas as crianças com 3 pontos morreram. Conclusões: a utilização de pressão positiva no final da expiração no TCE grave requer monitorização contínua da pressão intracraniana. A correção da hipertensão intracraniana e da instabilidade hemodinâmica são condições necessárias prévias ao tratamento.
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Objective:To investigate the role of chest wall elastic resistance in determining the effects of positive end-expiratory pressure (PEEP) on central venous pressure (CVP) in patients with mechanical ventilation (MV).Methods:In this prospective study, according to the median of ratio of chest wall elastic resistance to respiratory system elastic resistance (Ers), patients were divided into high chest wall elastic resistance group (Ecw/Ers≥0.24) and low chest wall elastic resistance group [elastance of chest wall (Ecw)/Ers<0.24]. PEEP was set at 5, 10, 15 cmH 2O (1 cmH 2O=0.098 kPa) respectively. Clinical data including CVP, heart rate (HR), blood pressure (BP) and respiratory mechanics were recorded. Results:Seventy patients receiving MV were included from November 2017 to December 2018. Clinical characteristics including age, BP, HR, baseline PEEP, the ratio of arterial oxygen partial pressure to fractional inspired oxygen (P/F) and comorbidities were comparable in two groups. However, patients with high Ecw/Ers ratio presented higher body mass index (BMI) than those with low Ecw/Ers ratio[ (25.4±3.2) kg/m 2 vs. (23.4±3.2) kg/m 2, P=0.011]. As PEEP increased from 5 cmH 2O to 10 cmH 2O, CVP in high Ecw/Ers group increased significantly compared with that in low Ecw/Ers group [1.75(1.00, 2.13) mmHg (1 mmHg=0.133kPa) vs. 1.50(0.50, 2.00)mmHg, P=0.038], which was the same as PEEP increased from 10 cmH 2O to 15 cmH 2O [2.00(1.50, 3.00)mmHg vs. 1.50(1.00, 2.00)mmHg, P=0.041] or PEEP increased from 5 cmH 2O to 15 cmH 2O [ 3.75(3.00,4.63)mmHg vs. 3.00(1.63, 4.00)mmHg, P=0.012]. When PEEP increased from 5 cmH 2O to 10 cmH 2O, 10 cmH 2O to 15 cmH 2O and 10 cmH 2O to 15 cmH 2O, there were significant correlations between Ecw/Ers and CVP elevation ( r=0.29, P=0.016; r=0.31, P=0.011; r=0.31, P=0.01 respectively). Conclusions:In patients receiving mechanical ventilation, elevation of PEEP leads to a synchronous change of CVP, which is corelated with patients′ chest wall elastic resistances.
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@#Objective To evaluate the effect of driving pressure-guided lung protective ventilation strategy on lung function in adult patients under elective cardiac surgery with cardiopulmonary bypass. Methods In this randomized controlled trial, 106 patients scheduled for elective valve surgery via median sternal incision under cardiopulmonary bypass from July to October 2020 at West China Hospital of Sichuan University were included in final analysis. Patients were divided into two groups randomly. Both groups received volume-controlled ventilation. A protective ventilation group (a control group, n=53) underwent traditional lung protective ventilation strategy with positive end-expiratory pressure (PEEP) of 5 cm H2O and received conventional protective ventilation with tidal volume of 7 mL/kg of predicted body weight and PEEP of 5 cm H2O, and recruitment maneuver. An individualized PEEP group (a driving pressure group, n=53) received the same tidal volume and recruitment, but with individualized PEEP which produced the lowest driving pressure. The primary outcome was oxygen index (OI) after ICU admission in 30 minutes, and the secondary outcomes were the incidence of OI below 300 mm Hg, the severity of OI descending scale (the Berlin definition), the incidence of pulmonary complications at 7 days after surgery and surgeons’ satisfaction on ventilation. Results There was a statistical difference in OI after ICU admission in 30 minutes between the two groups (273.5±75.5 mm Hg vs. 358.0±65.3 mm Hg, P=0.00). The driving pressure group had lower incidence of postoperative OI<300 mm Hg (16.9% vs. 49.0%, OR=0.21, 95%CI 0.08-0.52, P=0.00) and less severity of OI classification than the control group (P=0.00). The incidence of pulmonary complications at 7 days after surgery was comparable between the driving pressure group and the control group (28.3% vs. 33.9%, OR=0.76, 95%CI 0.33-1.75, P=0.48). The atelectasis rate was lower in the driving pressure group (1.0% vs. 15.0%, OR=0.10, 95%CI 0.01-0.89, P=0.01). Conclusion Application of driving pressure-guided ventilation is associated with a higher OI and less lung injury after ICU admission compared with the conventional protective ventilation in patients having valve surgery.
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RESUMO Objetivo: Avaliar se a diminuição da pressão arterial provocada pela elevação da pressão parcial positiva final corresponde à variação da pressão de pulso como indicador de fluido-responsividade. Métodos: Estudo de caráter exploratório que incluiu prospectivamente 24 pacientes com choque séptico ventilados mecanicamente e submetidos a três etapas de elevação da pressão parcial positiva final: de 5 para 10cmH2O (nível da pressão parcial positiva final 1), de 10 para 15cmH2O (nível da pressão parcial positiva final 2) e de 15 para 20cmH2O (nível da pressão parcial positiva final 3). Alterações da pressão arterial sistólica, da pressão arterial média e da variação da pressão de pulso foram avaliadas durante as três manobras. Os pacientes foram classificados como responsivos (variação da pressão de pulso ≥ 12%) e não responsivos a volume (variação da pressão de pulso < 12%). Resultados: O melhor desempenho para identificar pacientes com variação da pressão de pulso ≥ 12% foi observado no nível da pressão parcial positiva final 2: variação de pressão arterial sistólica de -9% (área sob a curva de 0,73; IC95%: 0,49 - 0,79; p = 0,04), com sensibilidade de 63% e especificidade de 80%. A concordância foi baixa entre a variável de melhor desempenho (variação de pressão arterial sistólica) e a variação da pressão de pulso ≥ 12% (kappa = 0,42; IC95%: 0,19 - 0,56). A pressão arterial sistólica foi < 90mmHg no nível da pressão parcial positiva final 2 em 29,2% dos casos e em 41,6,3% no nível da pressão parcial positiva final 3. Conclusão: Variações da pressão arterial em resposta à elevação da pressão parcial positiva final não refletem de modo confiável o comportamento da variação da pressão de pulso para identificar o status da fluido-responsividade.
Abstract Objective: To evaluate whether the decrease in blood pressure caused by the increase in the positive end-expiratory pressure corresponds to the pulse pressure variation as an indicator of fluid responsiveness. Methods: This exploratory study prospectively included 24 patients with septic shock who were mechanically ventilated and subjected to three stages of elevation of the positive end-expiratory pressure: from 5 to 10cmH2O (positive end-expiratory pressure level 1), from 10 to 15cmH2O (positive end-expiratory pressure level 2), and from 15 to 20cmH2O (positive end-expiratory pressure level 3). Changes in systolic blood pressure, mean arterial pressure, and pulse pressure variation were evaluated during the three maneuvers. The patients were classified as responsive (pulse pressure variation ≥ 12%) or unresponsive to volume replacement (pulse pressure variation < 12%). Results: The best performance at identifying patients with pulse pressure variation ≥ 12% was observed at the positive end-expiratory pressure level 2: -9% systolic blood pressure variation (area under the curve 0.73; 95%CI: 0.49 - 0.79; p = 0.04), with a sensitivity of 63% and specificity of 80%. Concordance was low between the variable with the best performance (variation in systolic blood pressure) and pulse pressure variation ≥ 12% (kappa = 0.42; 95%CI: 0.19 - 0.56). The systolic blood pressure was < 90mmHg at positive end-expiratory pressure level 2 in 29.2% of cases and at positive end-expiratory pressure level 3 in 41.63% of cases. Conclusion: Variations in blood pressure in response to the increase in positive end-expiratory pressure do not reliably reflect the behavior of the pulse pressure as a measure to identify the fluid responsiveness status.
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Humans , Male , Female , Adult , Middle Aged , Aged , Shock, Septic/therapy , Blood Pressure/physiology , Positive-Pressure Respiration , Fluid Therapy/methods , Respiration, Artificial , Shock, Septic/physiopathology , Prospective Studies , Sensitivity and SpecificityABSTRACT
OBJECTIVE@#To investigate the effect of inverse ratio ventilation (IRV) combined with positive end-expiratory pressure (PEEP) in infants undergoing thoracoscopic surgery with single lung ventilation (OLV) for lung cystadenomas.@*METHODS@#A total of 66 infants undergoing thoracoscopic surgery with OLV for lung cystadenomas in our hospital from February, 2018 to February, 2019 were randomized into conventional ventilation groups (group N, =33) and inverse ventilation group (group R, =33). Hemodynamics and respiratory parameters of the infants were recorded and arterial blood gas analysis was performed at 15 min after two lung ventilation (TLV) (T), OLV30 min (T), OLV60 min (T), and 15 min after recovery of TLV (T). Bronchoalveolar lavage fluid was collected before and after surgery to detect the expression level of advanced glycation end product receptor (RAGE).@*RESULTS@#Sixty-three infants were finally included in this study. At T and T, Cdyn, PaO and OI in group R were significantly higher ( < 0.05) and Ppeak, PaCO and PA-aO were significantly lower than those in group N ( < 0.05). There was no significant difference in HR or MAP between the two groups at T and T ( > 0.05). The level of RAGE significantly increased after the surgery in both groups ( < 0.05), and was significantly lower in R group than in N group ( < 0.05).@*CONCLUSIONS@#In infants undergoing thoracoscopic surgery with OLV for pulmonary cystadenoma, appropriate IRV combined with PEEP does not affect hemodynamic stability and can increases pulmonary compliance, reduce the peak pressure, and improve oxygenation to provide pulmonary protection.
Subject(s)
Humans , Infant , Cystadenoma , Therapeutics , Lung , One-Lung Ventilation , Positive-Pressure Respiration , ThoracoscopyABSTRACT
RESUMEN Objetivo: Comparar las medidas de gasto cardiaco por ecocardiografía transtorácica y por catéter arterial pulmonar en pacientes en ventilación mecánica con presión positiva al final de la espiración elevada. Evaluar el efecto de la insuficiencia tricúspide. Métodos: Se estudiaron 16 pacientes en ventilación mecánica. El gasto cardiaco se midió con el catéter arterial pulmonar y por ecocardiografía transtorácica. Las medidas se realizaron en diferentes niveles de presión positiva al final de la espiración (10cmH2O, 15cmH2O, y 20cmH2O). Se evalúo el efecto de la insuficiencia tricúspide sobre la medida de gasto cardiaco. Se estudió el coeficiente de correlación intraclase; el error medio y los límites de concordancia se estudiaron con el diagrama de Bland-Altman. Se calculó el porcentaje de error. Resultados: Se obtuvieron 44 pares de medidas de gasto cardiaco. Se obtuvo un coeficiente de correlación intraclase de 0,908, p < 0,001; el error medio fue 0,44L/min para valores de gasto cardíaco entre 5 a 13L/min. Los límites de concordancia se encontraron entre 3,25L/min y -2,37L/min. Con insuficiencia tricúspide el coeficiente de correlación intraclase fue 0,791, sin insuficiencia tricúspide el coeficiente de correlación intraclase fue 0,935. La presencia de insuficiencia tricúspide aumentó el porcentaje de error de 32 % a 52%. Conclusiones: En pacientes con presión positiva al final de la espiración elevada la medida de gasto cardiaco por ecocardiografía transtorácica es comparable con catéter arterial pulmonar. La presencia de insuficiencia tricúspide influye en el coeficiente de correlación intraclase. En pacientes con presión positiva al final de la espiración elevada, el uso de ecocardiografía transtorácica para medir gasto cardiaco es comparable con las medidas invasivas.
ABSTRACT Objective: To compare cardiac output measurements by transthoracic echocardiography and a pulmonary artery catheter in mechanically ventilated patients with high positive end-expiratory pressure. To evaluate the effect of tricuspid regurgitation. Methods: Sixteen mechanically ventilated patients were studied. Cardiac output was measured by pulmonary artery catheterization and transthoracic echocardiography. Measurements were performed at different levels of positive end-expiratory pressure (10cmH2O, 15cmH2O, and 20cmH2O). The effect of tricuspid regurgitation on cardiac output measurement was evaluated. The intraclass correlation coefficient was studied; the mean error and limits of agreement were studied with the Bland-Altman plot. The error rate was calculated. Results: Forty-four pairs of cardiac output measurements were obtained. An intraclass correlation coefficient of 0.908 was found (p < 0.001). The mean error was 0.44L/min for cardiac output values between 5 and 13L/min. The limits of agreement were 3.25L/min and -2.37L/min. With tricuspid insufficiency, the intraclass correlation coefficient was 0.791, and without tricuspid insufficiency, 0.935. Tricuspid insufficiency increased the error rate from 32% to 52%. Conclusions: In patients with high positive end-expiratory pressure, cardiac output measurement by transthoracic echocardiography is comparable to that with a pulmonary artery catheter. Tricuspid regurgitation influences the intraclass correlation coefficient. In patients with high positive end-expiratory pressure, the use of transthoracic echocardiography to measure cardiac output is comparable to invasive measures.