Estrategias de ventilación protectora en cirugía cardiovascular / Protective ventilation strategies in cardiovascular surgery

Introducción: La alteración en el intercambio gaseoso es una complicación de la cirugía cardíaca con circulación extracorpórea. La causa de este deterioro es multifactorial. Durante la derivación, ambos pulmones colapsan y al término de la circulación extracorpórea los pulmones se vuelven a expandir, sin existir una técnica estándar para ello. La aplicación de reclutamiento alveolar durante la anestesia general en este tipo de cirugía mejora la oxigenación arterial. Objetivo: Describir aspectos esenciales de fisiopatología de la injuria pulmonar asociada a la ventilación mecánica en procedimientos quirúrgicos cardíacos y el efecto de la ventilación mecánica protectora perioperatoria como estrategia para prevenirla. Método: Se realizó una búsqueda de la literatura publicada durante el período comprendido entre enero de 1990 y diciembre de 2020 que hiciera referencia a las estrategias de ventilación mecánica protectora en cirugía cardiovascular. Resultados: La evidencia experimental y clínica sugiere que los bajos volúmenes corrientes de ventilación pulmonar y la aplicación por un corto período del aumento de las presiones inspiratorias, conocidas como "maniobras de reclutamiento" seguidas de la aplicación de presión positiva al final de la espiración para mantener los alveolos reclutados abiertos, incrementan la capacidad residual funcional y reducen la injuria pulmonar asociada a la ventilación mecánica. Estas recomendaciones han sido extrapoladas de estudios retrospectivos realizados en otro tipo de poblaciones. Conclusiones: No existe evidencia contundente de que esta estrategia disminuya la respuesta proinflamatoria, mejore la función pulmonar posoperatoria y disminuya la mortalidad perioperatoria, cuando se compara con la ventilación convencional(AU)

Introduction: The alteration in gas exchange is a complication of cardiac surgery with extracorporeal circulation. The cause of this deterioration is multifactorial. During the shunt, both lungs collapse and at the end of the extracorporeal circulation the lungs expand again, without a standard technique for it. The application of alveolar recruitment during general anesthesia in this type of surgery improves arterial oxygenation. Multiple strategies are used and have as a reference the extracorporeal circulation and its contribution to the pulmonary and systemic inflammatory response. This forces the anesthesiologist to understand the pathophysiology of lung injury associated with mechanical ventilation. Objective: Describe essential aspects of pathophysiology of pulmonary injury associated with mechanical ventilation in cardiac surgical procedures and the effect of perioperative protective mechanical ventilation as a strategy to prevent it. Method: A search of the literature published during the period between January 1990 and December 2020 was carried out that referred to protective mechanical ventilation strategies in cardiovascular surgery. Results: Experimental and clinical evidence suggest that low current volumes of pulmonary ventilation and the application for a short period of increased inspiratory pressures, known as "recruitment maneuvers" followed by the application of positive pressure at the end of expiration to keep the recruited alveoli open, increase functional residual capacity and reduce lung injury associated with mechanical ventilation. These recommendations have been extrapolated from retrospective studies conducted in other types of populations. Conclusions: There is no strong evidence that this strategy decreases the pro-inflammatory response, improves postoperative lung function and decreases perioperative mortality, when compared to conventional ventilation(AU)

Effects on extravascular lung water of lung protective ventilation strategy applied on piglets with acute respiratory distress syndrome induced by paraquat / 中华劳动卫生职业病杂志

Objective: To study the effects on extravascular lung water of lung protective ventilation strategy applying on piglets with acute respiratory distress syndrome (ARDS) induced by paraquat (PQ) under pulse indicating continuous cardiac output (PiCCO) monitoring. Methods: The piglets models with ARDS induced by PQ were established in June 2020 and all of them were received mechanical ventilation and divided into three groups according to tidal volume (V(T)) : small V(T) group (6 ml/kg) , middle V(T) group (10 ml/kg) and large V(T) group (15 ml/kg) , there were 5 piglets in each group. The positive end expiratory pressure (PEEP) were all setup on 10 cmH(2)O. The indexes such as arterial blood gas analysis, oxygenation index (OI) , extravascular lung water index (ELWI) and pulmonary vascular permeability index (PVPI) were monitored at time of before the model was established (baseline) , time of the model was established (t(0)) and 2 h (t(2)) , 4 h (t(4)) , 6 h (t(6)) after mechanical ventilation. Lung tissue were punctured at time of baseline, t(0) and t(6) to be stained by Hematoxylin-eosin (HE) staining and pulmonary pathology were observed under light microscopy. Results: The heart rate (HR) , mean arterial pressure (MAP) and partial pressure of carbon dioxide (PaCO(2)) of all groups were higher than the base value while the pH values, partial pressure of oxygen (PaO(2)) and OI were lower than the base value when the models were established (P<0.05) . After mechanical ventilation, the HR and MAP values of all groups at t(2), t(4) and t(6) were lower than t(0) while the PaCO(2) of t(4) and t(6) were all higher than t(0), the differences were statistically significant (P<0.05) . The PaO(2) and OI of all groups showed a trend of rising at first and then decreasing after mechanical ventilation. The MAP, PaO(2), PaCO(2) and OI of the middle V(T) group and large V(T) group were apparently lower than that of the small V(T) group at t(2), t(4) and t(6) (P<0.05) . The ELWI and PVPI at t(0) of all groups were higher than that of baseline (P<0.05) . The ELWI of the small V(T) group at t(6) were lower than t(0) of the same group and t(6) of the middle V(T) group and large V(T) group (P<0.05) . HE staining showed congestion and edema of alveolar tissue, swelling of capillaries, exudation of red blood cells and widening of alveolar septum in piglets after successful modeling. And further widening of alveolar septum and rupture of alveolar septum could be seen in the lung tissues of each group at t(6), and the injury was the slightest in the small V(T) group. Conclusion: The lung protective ventilation strategy can alleviate the extravascular lung water and ARDS induced by PQ and improve oxygenation.

Implementation of individualized lung protective ventilation strategy for pediatrics acute respiratory distress syndrome guided by electrical impedance tomography and critical care ultrasound / 中国小儿急救医学

Objective:To explore the implementation of individualized lung protection ventilation strategy in pediatric acute respiratory distress syndrome(pARDS)guided by transthoracic electrical impedance tomography(EIT)and critical care ultrasound(CCU).Methods:We retrospectively analyzed the therapeutic process of protective ventilation strategy in one case of severe pARDS.EIT and CCU were used to guide the implementation of lung protective ventilation strategy.Results:EIT was used to guide lung recruitment and optimal positive end-expiratory pressure titration.CCU was used to assess hemodynamics and lung status of ARDS patient, and guide the implementation of right ventricular protective ventilation and circulatory protective ventilation.Finally, the patient eventually survived.Conclusion:The idea of ARDS protective ventilation has changed from traditional lung protective ventilation to right heart protective ventilation and circulatory protective ventilation, and finally achieved the protection of pulmonary vascular endothelium.EIT and CCU enrich the understanding of the pathophysiology and protective ventilation strategy in pARDS.

Effect of driving pressure-guided lung protective ventilation strategy on early postoperative pulmonary function in adults patients undergoing heart valve surgery: A randomized controlled study / 中国胸心血管外科临床杂志

@#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.

Intermittent two-lung ventilation during minimally invasive coronary artery bypass grafting on the application of triangular-sail technique / 中国胸心血管外科临床杂志

@#Objective    To analyze the feasibility of using triangular-sail technique that allows intermittent two-lung ventilation during minimally invasive coronary artery bypass grafting (MICS CABG). Methods    The clinical data of 207 patients with MICS CABG in our cardiac center from January 2019 to November 2020 were retrospectively analyzed. These patients were divided into two groups. A group OLV included 111 patients who underwent one-lung ventilation during surgery, while a group TLV included 96 patients who underwent intermittent two-lung ventilation. The triangular-sail technique was used in the group TLV. This simple technique isolated the operative field from lung lobes with the traction of pericardial adipose tissue. The preoperative data and perioperative clinical data of the two groups were compared and analyzed. Results    There was no statistical difference in basic preoperative data between the two groups. The operation time in the OLV group was shorter than that in the TLV group (296.7±57.3 min vs. 334.1±87.0 min, P=0.000), and the duration of postoperative mechanical ventilation and ICU stay were not statistically different between the two groups. There was also no statistical difference in the incidence of pneumothorax or atelectasis between the two groups. Conclusion    The triangular-sail technique is simple and easy to implement. The technique allows intermittent two-lung ventilation during MICS CABG procedure.

Research progress of spontaneous respiration in mechanical ventilation of acute respiratory distress syndrome / 中华危重病急救医学

Mechanical ventilation is an important supportive treatment for acute respiratory distress syndrome (ARDS). However, improper mechanical ventilation can cause a "second hit" to the lung, that is, ventilator-induced lung injury (VILI), characterized by translocation of pulmonary inflammatory mediators into the bloodstream, aggravating systemic inflammatory response syndrome, and multiple organ failure. Although the current protective mechanical ventilation strategy plays an important role in supporting treatment, the mortality of ARDS with mechanical ventilation is still very high. Therefore, to explore the strategy of pulmonary protective ventilation has always been the key orientation of ARDS and has important clinical significance. This article reviews the application, advantages and disadvantages of assisted and non-assisted spontaneous respiration in ARDS patients undergoing mechanical ventilation, in order to provide a reference for research and development of new strategies for ARDS protective ventilation.

Dexmedetomidine combined with protective lung ventilation strategy provides lung protection in patients undergoing radical resection of esophageal cancer with one-lung ventilation / 南方医科大学学报

OBJECTIVE@#To investigate the effect of dexmedetomidine combined with pulmonary protective ventilation against lung injury in patients undergoing surgeries for esophageal cancer with one-lung ventilation (OLV).@*METHODS@#Forty patients with undergoing surgery for esophageal cancer with OLV were randomly divided into pulmonary protective ventilation strategy group (F group) and dexmedetomidine combined with protective ventilation strategy group (DF group; =20). In F group, lung protective ventilation strategy during anesthesia was adopte, and in DF group, the patients received intravenous infusion of dexmedetomidine hydrochloride (0.3 μg · kg ·h) during the surgery starting at 10 min before anesthesia induction in addition to protective ventilation strategy. Brachial artery blood was sampled before ventilation (T), at 30 and 90 min after the start of OLV (T and T, respectively) and at the end of the surgery (T) for analysis of superoxide dismutase (SOD), malondialdehyde (MDA), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), arterial oxygenation pressure (PaO), oxygenation index (OI) and lung compliance (CL).@*RESULTS@#At the time points of T, T and T, SOD level was significantly higher and IL-6 level was significantly lower in the DF group than in F group ( < 0.05). The patients in DF group showed significantly higher PaO, OI and CL index than those in F group at all the 3 time points.@*CONCLUSIONS@#Dexmedetomidine combined with pulmonary protective ventilation strategy can reduce perioperative lung injury in patients undergoing surgery for esophageal cancer with OLV by suppressing inflammation and oxidative stress to improve lung function and reduce adverse effects of the surgery.

Pediatric acute respiratory distress syndrome: from lung protective ventilation to extracorporeal membrane oxygenation / 中华实用儿科临床杂志

Pediatric acute respiratory distress syndrome (PARDS) is the most leading cause of death in Pediatric Intensive Care Unit.PARDS can be classified as mild, moderate, and severe according to the oxygenation index.In recent years, because of the application of lung protection ventilation strategy, the outcome of PARDS has been greatly improved, but the mortality of severe PARDS still remains high.Therefore, it is of great clinical significance to understand the definition, diagnosis, and the application of lung protective ventilation strategy and the application of extracorporeal membrane oxygenation in severe PARDS.

Right heart protective ventilation strategy in children with acute respiratory distress syndrome / 中国小儿急救医学

Acute respiratory distress syndrome (ARDS) can cause pulmonary vascular dysfunction, increase right ventricular afterload and lead to right ventricular failure,also known as acute cor pulmonale. Mechanical ventilation to maintain oxygenation and ventilation has a negative impact on right ventricular function,which may lead to lung-right ventricular interaction and aggravate the deterioration of right ventricu-lar failure,which may be one of the causes of right ventricular failure. Therefore,in the treatment of mechani-cal ventilation for ARDS,attention must be paid to the right ventricular function of patients.

Effect of intraoperative lung-protective mechanical ventilation on pulmonary oxygenation function and postoperative pulmonary complications after laparoscopic radical gastrectomy

This study aimed to observe the effects of lung-protective ventilation (LPV) on oxygenation index (OI) and postoperative pulmonary complications (PPCs) after laparoscopic radical gastrectomy in middle-aged and elderly patients. A total of 120 patients who were scheduled to undergo laparoscopic radical gastrectomy with an expected time of >3 h were randomly divided into conventional ventilation (CV group) with tidal volume (TV) of 10 mL/kg without positive end-expiratory pressure (PEEP), and lung-protective ventilation (PV group) with 7 mL/kg TV and personal level of PEEP with regular recruitment maneuver every 30 min. Measurements of OI, modified clinical pulmonary infection score (mCPIS), and PPCs were assessed during the perioperative period. Fifty-seven patients in the CV group and 58 in the PV group participated in the data analysis. Patients in the PV group showed better pulmonary dynamic compliance, OI, and peripheral capillary oxygen saturation during and after surgery. The mCPIS was significantly lower in the PV group than in the CV group after surgery. The incidence rate of PPCs was lower in the PV group than in the CV group and the difference was significant in patients whose ventilation time was longer than 6 h in both groups. LPV during laparoscopic radical gastrectomy significantly improved pulmonary oxygenation function and reduced postoperative mCPIS and the incidence of PPCs during the early period after surgery of middle-aged and elderly patients, especially patients whose mechanical ventilation time was longer than 6 h.

Perioperative use of lung protective ventilation strategy on immune function in patients undergoing thoracoscopic radical resection of lung cancer / 临床麻醉学杂志

Objective To evaluate the lung protective ventilation strategy on immune function in patients undergoing radical resection of lung cancer.Methods Sixty patients undergoing thoracoscopic radical resection of lung cancer, 47 males and 13 females, aged 35-64 years, BMI 18-29 kg/m2, falling into ASA physical statusⅠ orⅡ, were randomly divided into 2 groups with 30 cases in each:conventional mechanical ventilation (group C), protective mechanical ventilation group (group P).Volume-controlled ventilation was performed in the 2 groups.Protective mechanical ventilation mode was setted up as follows:tidal volume (VT) 8 ml/kg and respiratory rate (RR) 12-14 breaths/min during two-lung ventilation (TLV) ;VT 6 ml/kg, PEEP 5 cm H2O and RR 14-16 breaths/min during one-lung ventilation (OLV).Before induction of anesthesia (T0), at the end of surgery (T1), 24 hafter surgery (T2), 72 hafter surgery (T3), blood samples were taken from the central venous for determination of peripheral T lymphocyte subsets CD3+, CD4+, CD8+ and NK cell.The CD4+/CD8+ratio was also calculated.Results Compared with T0, the percentage of CD3+, CD4+, NK cell and the CD4+/CD8+ratio was significantly decreased at T1 and T2 in both groups (P<0.05).Compared with group P, the percentage of CD3+, CD4+, NK cell and the CD4+/CD8+ratio was significantly lower in the group C at T1 and T2 (P<0.05).Compared with T0, there was no significant difference at T3 with respect of the percentage of CD3+, CD4+, NK cell and the CD4+/CD8+ratio in the group P while those parameters still lower at T3 in the group C (P<0.05).Conclusion Perioperative use of lung protective ventilation strategy could not only alleviate the immune suppression but also make the immune function recover faster in patients undergoing thoracoscopic elective radical resection of lung cancer.

Effect of sequential pulmonary resuscitation maneuver with lung protective ventilation on hemodynamics and arterial blood gas in patients with acute respiratory distress syndrome caused by severe chest trauma / 中国中西医结合急救杂志

Objective To investigate the effects of sequential pulmonary resuscitation maneuver (RM) with pulmonary protective ventilation on hemodynamics and arterial blood gas in patients with acute respiratory distress syndrome (ARDS) caused by severe chest trauma. Methods Ninety-six ARDS patients caused by severe chest trauma admitted to Dongguan People's Hospital from January 2017 to December 2018 were enrolled, and they were divided into a RM group and a mechanical ventilation group according to different ventilation modes, 48 cases being in each group. The mechanical ventilation group was given low tidal volume ventilation combined with the best positive end-expiratory pressure (PEEP); while the RM group was given sequential lung RM therapy on the basis of treatment in the mechanical ventilation group. The heart rate (HR), mean arterial pressure (MAP), central venous pressure (CVP), cardiac output (CO), cardiac output index (CI), systemic circulation resistance index (SVRI) arterial blood gas were monitored before and after treatment in the two groups, and oxygenation index(PaO2/FiO2) was calculated; The mechanical ventilation time, intensive care unit (ICU) hospitalization time, incidence of ventilator associated pneumonia (VAP), mortality and incidence of adverse reaction were observed between the two groups. Results After treatment, the pH value and arterial partial pressure of carbon dioxide (PaCO2) of the two groups had no significant change; with the prolongation of treatment, the arterial partial pressure of oxygen (PaO2) and arterial blood oxygen saturation (SaO2);PaO2/FiO2 were increased significantly, total carbon dioxide (TCO2) was decreased significantly, after 72 hours of treatment, the degree of change in the RM group were more remarkable greater than those in the mechanical ventilation group [PaO2 (mmHg, 1 mmHg = 0.133 kPa): 91.02±9.03 vs. 80.34±7.66, SaO2: 0.96±0.04 vs. 0.94±0.04, TCO2 (mmol/L): 24.72±2.83 vs. 23.54±2.76, PaO2/FiO2 (mmHg): 238.47±19.83 vs. 185.34±17.37, all P < 0.05]. The ICU hospitalization time and mechanical ventilation time in the RM group were significantly lower than those in the mechanical ventilation group [ICU hospitalization time (days): 22.03±3.39 vs. 26.75±4.04,mechanical ventilation time (days): 13.38±4.04 vs. 19.33±5.02], and the incidence of VAP and mortality in the RM group were significantly lower than those in the mechanical ventilation group[incidence of VAP: 25.00% (12/48) vs. 8.33% (4/48), mortality: 18.75% (9/48) vs. 22.92% (11/48), both P < 0.05]. With the extension of time, CVP, MAP, CO, CI and SVRI in RM group all showed a trend of first decreasing and then increasing, while HR showed a trend of increasing and then decreasing, and the above indicators in 5 minutes after pulmonary re-opening, gradually returned to normal, showing no statistical significances compared with those before treatment [HR (bpm): 97.88±6.22 vs. 98.20±8.37, CVP (mmHg): 6.33±1.35 vs. 6.32±1.36, MAP (mmHg): 94.56±5.96 vs. 95.03±9.82, CO (L/min): 6.34±1.42 vs. 6.40±1.23, CI (L·min-1·s-1):2.08±0.32 vs. 2.17±0.53, SVRI: 2 404.34±31.34 vs. 2 474.34±29.73, all P > 0.05]. No adverse reactions occurred in the two groups. Conclusion Pulmonary protective ventilation sequential lung recruitment maneuver can significantly improve the oxygenation of ARDS caused by severe chest trauma, shorten the durations of mechanical ventilation and hospitalization in ICU, reduce the incidence of VAP, improve pulmonary inflammation, and in the mean time it has no serious adverse effects on hemodynamics.

Application of lung protective ventilation strategy in radiofrequency ablation of atrial fibrillation / 实用医学杂志

Objective To observe the clinical significance of lung protective ventilation strategy in pa-tients with radiofrequency ablation of atrial fibrillation under general anesthesia through clinical controlled study. Methods Sixty patients undergoing radiofrequency catheter ablation were randomly divided into group L (n=30) and group C(n=30).Breathing parameters were set after tracheal intubation of general anesthesia.Arterial blood gas was collected.PETCO2and airway pressure were recorded during the operation.The operative time,ablation time,flu-oroscopy time and operation-related complications were recorded together with the surgeon satisfaction. Patients were followed up postoperatively for pulmonary complications. The length of patient′s hospital-stay was recorded. Results There was no significant difference in operation time, fluoroscopy time, ablation time and hospitalization days between the two groups (P>0.05). There was no significant difference in the occurrence and grade of PPCs between the two groups (P>0.05). There was significant difference in surgeon satisfaction between the two groups (P<0.01).Conclusion LPVS is suitable for ventilation management in radiofrequency ablation of atrial fibrillation.

Clinical Observation of Lung Protective Ventilation Strategy in Gynecologic Laparoscopic Surgery / 实用妇产科杂志

Objective:By monitoring the lung compliance,oxygenation index(OI),CC16、IL-8 in plasma,observe whether the protective lung ventilation in patients undergoing gynecological laparoscopic surgery can improve the respiratoryw function and reduce lung injury.Methods:40 cases of ASA grade Ⅰ-Ⅱ were selected,and 40 patients were treated by elective laparoscopic radical resection of cervical cancer.The patients were divided into two groups according to the random number table method in 40 cases.Mechanical ventilation in general anesthesia,A group used traditional intermittent positive pressure ventilation mode,tidal volume is set to 10ml/KG (PBW);B group used lung protective ventilation strategy,tidal volume is set to 6ml/KG (PBW) + 5cmH2O PEEP + recruitment manoeuvres.For patients before pneumoperitoneum(T0),2 hours after pneumoperitoneum (T1),4 hours after pneumoperitoneum (T2)MAP,HR,CVP,RR and C were observed.In pneumoperitoneum (T0),2 hours after pneumoperitoneum(T1),4 hours after pneumoperitoneum (T2),2 hours after operation(T3),24 hours after surgery(T4) venous,IL-8,CC16 content detection.Results:Before pneumoperitoneum,two groups of patients with pulmonary compliancethe difference was statistically significant(P ＜0.05).Compared T1 、T2 with T0 in A group and B group,the pulmonary compliance all decreased and there existed significant deference(P＜0.05).Notably,A group decreased evidently(P＜0.05).T0,T1,T3,T4 time points in two groups of patients with oxygenation index,the difference was statistically significant (P ＜ 0.05).Two groups of patients with CC16,IL-8content in T1,T2,T3,T4 time point,the difference was statistically significant (P ＜ 0.05).Conclusions:Lung protective ventilation strategy can improve respiratory function in patients with gynecological laparoscopic surgery,and reduce the incidence of lung injury.

The clinical application of tracheal gas insufflation / 中国小儿急救医学

Tracheal gas insufflation is a non conventional respiratory support technology. It might avoid severe CO2 retention in lung protective ventilation strategy, reduce ventilator-associated lung injury, which was recommented recently. In this article,we made a brief introduction of the principle,classification and clinical applications of tracheal gas insufflation technique.

Effect of low tidal volume lung protective ventilation strategy on the outcome of elderly patients with poor pulmonary function after abdominal operation / 临床麻醉学杂志

Objective To observe the effect of low tidal volume lung protective ventilation management strategy on postoperative outcome of elderly patients with poor pulmonary function after abdominal surgery.Methods Eighty patients of poor pulmonary function undergoing open gastrointestinal surgery,male 64 cases,female 16 cases,aged over 65 years old,ASA physical status Ⅱ or Ⅲ,NYHA cardiac function Ⅱ or Ⅲ grade,expected operation time 2-4 h were screened.The patients were randomly divided into 2 groups: protective ventilation management group (group P) and conventional mechanical ventilation group (group C),40 cases in each group.Multi-mode anesthetic management was performed in both groups.The respiratory parameters were adjusted according to the group after tracheal intubation,and the respiratory rate was adjusted to maintain PETCO2 35-45 mm Hg.The blood gas evaluated postoperative oxygen and postoperative spontaneous breathing recovery time,recovery time,extubation time,PACU time,gastrointestinal function recovery time,ambulation time,hospital stay and cost of hospitalization were recorded.The occurrence of major complications were observed at 30 days after surgery.Results PaO2 of group C was significantly decreased at 1 and 3 days after surgery than that before operation (P<0.05),PaCO2 of group C was significantly higher at 1 and 3 days after surgery than that of group P (P<0.05);PACU residence time of group P was (76.63±29.72) min,significantly shorter than that of group C [(93.80±42.90) min] (P<0.05);The difference spontaneous breathing recovery time,awake time,extubation time,exhaust time,ambulation time,postoperative hospitalization time and hospitalization expenses of two group was not statistically significant.Within 30 d after operation,2 cases (5%) of respiratory failure patients,3 cases (7.5%) of pneumonia in group P;5 cases (12.5%)of respiratory failure patients,3 cases (7.5%) of pneumonia,postoperative hemorrhage in 1 cases (2.5%) and 1 cases (2.5%) delirium in group C,there was no significant difference of the main complications in 30 d after operation between two groups.Conclusion Under the condition of this research,low tidal volume lung protective ventilation management strategy can improve elderly patients with poor pulmonary function after abdominal surgery postoperative oxygen and help to reduce the occurrence of postoperative adverse reactions.

A systematic evaluation of protective ventilation for surgery in the prone position / 基础医学与临床

Objective To evaluate protective ventilation(PV) versus conventional ventilation(CV) for surgery in the prone position.Methods We searched PubMed, Embase, the Cochrane Library, WanFang Data and other Chinese databases to collect the randomized controlled trails (RCTs) on intraoperative PV in comparison with CV for surgery in the prone position.Two authors independently identified the studies, performed data extraction and assessed the risks of bias in the included studies according to the Cochrane Handbook for Systematic Reviews of Interventions.The reviewers conducted data analyses with RevMan software.Results A total of 9 RCTs involving 449 participants were included.The results showed that the incidence of postoperative pulmonary complications (RR 0.30, 95% CI 0.12~0.73, P<0.01) and peak pressure (MD-3.52, 95% CI-6.93~-0.11, P<0.05) were lower in the PV group.Intraoperative PaO2/FiO2 was higher (MD 37.28, 95% CI 22.67~51.89, P<0.001) and alveolar-arterial oxygen difference was lower (MD-45.50, 95% CI-61.35~-29.65, P<0.001) in the PV group.Conclusions Low tidal volume ventilation in combination with positive end-expiratory pressure (with or without recruitment maneuver) decreases postoperative pulmonary complications,reduces peak pressure and improves oxygenation for surgery in the prone position.

The strategy of pulmonary protective ventilation after cardiac arrest resuscitation in critical ill children and the follow-up study / 中华实用儿科临床杂志

Objective To investigate the strategy of cardiopulmonary resuscitation (CPR) after lung protective mechanical ventilation in critical children and follow-up study of the survivals 90 d after discharge.Methods Four hundred and eighty-nine cases of respiratory cardiac arrest which occurred for various reasons from January 2011 to June 2016 were analyzed in Pediatric Intensive Care Unit (PICU) in Guiyang Children's Hospital,in which mechanical ventilation was performed after CPR in 251 cases,death,or giving up treatment within 24 h in 83 cases,children surviving ＞ 24 h in 168 cases,118 cases were assigned into small tidal volume ventilation group,and 50 cases into conventional tidal volume ventilation group,and according to the tidal volume to adjust positive end expiratory pressure ventilation (PEEP),and the oxygen partial pressure [pa (O2)] and the oxygen index (OI),the change of the indexes of blood gas analysis,lactic acid clearance,and oxygenation were also observed.To observe the complications of mechanical ventilation,the situation of withdrawing machine as well as the outcome of the children.Follow-up was conducted for 90 d,including continuous respiratory symptoms,lung imaging examination after discharge and lung function,nervous system examination.Results (1) After mechanical ventilation treatment of 48 hours,compared with the levels of fractional inspired oxygen (FiO2) (0.42 ± 0.15 vs.0.43 ± 0.22),pa (O2) (8.25 ± 0.22 vs.8.27 ± 0.68),OI (5.33 ± 2.01 vs.6.59 ± 1.99) and lactic acid clearance(61.05 ± 1.87 vs.60.93 ± 2.71) between the routine tidal volume ventilation group and the lower tidal volume ventilation group,showing that the difference had no statistical significance (t =1.645,1.165,2.302,2.037,all P ＞ 0.05).(2) In small tidal volume group,the incidence of ventilator associated lung injury was significantly lower than that in the conventional tidal volume group,and the difference was statistically significant (x2 =5.873,P ＜ 0.05).(3) Comparing 2 groups of different tidal volume ventilation,the mortality of critical ill children had no statistically significant difference (x2 =1.063,P ＞ 0.05).(4) One hundred and twenty-seven cases of children survived and were discharged,and compared with their discharge,the follow-up of 62 cases after discharge for 30 d,90 d showed that all the children's lung function improved,tidal volume,inspiratory and expiratory time ratio(I/E),volume ratio of peak(VP/VE),time ratio of peak(TP/TE) and breathing rate(RR) were also improved,and there was significant difference (F =43.225,6.108,68.821,78.237,20.361,all P ＜ 0.05).(5) Neurological examination and children's brain function classification rating scale showed that some children had nerve dysfunction.Conclusions Small tidal volume ventilation in reducing the occurrence of ventilator associated lung injury is superior to the conventional tidal volume ventilation.To improve case fatality rate of the children with cardiac arrest resuscitation and oxygenation is not better than the conventional tidal volume group.Dynamic monitoring is helpful to adjust breathing mechanics indexes and parameters and ventilator.Through the follow-up most of the discharged children recovered well,but a few had recurrent respiratory infection and neurological sequelae.

A clinical study of lung protective ventilation and sequential lung recruitment maneuver for treatment of severe acute pancreatitis complicated with acute respiratory distress syndrome / 中国中西医结合急救杂志

Objective To investigate the clinical therapeutic effects of lung protective ventilation and sequential recruitment maneuver (RM) on treatment of patients with severe acute pancreatitis (SAP) complicated with acute respiratory distress syndrome (ARDS). Methods Sixty patients with SAP complicated with ARDS admitted to the Department of Critical Care Medicine of the First Affiliated Hospital of Nanchang University from April 2014 to March 2016 were enrolled. They were divided into control group and experimental group by random number table, 30 patients in each group. On the basis of comprehensive treatment, the patients in control group were treated with lung protective ventilation mode: low tidal volume ventilation (6 mL/kg) + optimal end-expiratory positive pressure (PEEP) ventilation mode, when the intra-abdominal pressure (IAP) was essentially returned to a normal level (Ⅰ grade intra-abdominal hypertension), the patients in experimental group were treated by the combination with RM therapy, and the rest treatment was the same as the control group. Under the two types of ventilation strategies, the clinical effects, respiratory mechanics, hemodynamics and arterial blood gas indexes were compared between the two groups. Results The mechanical ventilation time (days: 13.82±4.40 vs. 19.87±7.40), the length of ICU stay (days:22.67±4.40 vs. 26.43±5.39) and incidence of ventilator associated pneumonia [VAP: 16.67% (5/30) vs. 26.67% (8/30)] of the experimental group were lower than those of the control group (all P < 0.05), the mortality rate of the experimental group was slightly lower than that of the control group [26.67% (8/30) vs. 30.00% (9/30)] without statistical significance (P > 0.05). Plateau pressure (Pplat) and the peak airway pressure (PIP) at each time point were decreased after treatment in both groups, while the static lung compliance (Cst), the arterial partial pressure of oxygen (PaO2) and oxygenation index (PaO2/FiO2) were increased compared with those before treatment, especially the changes at 72 hours after recruitment in the experimental group were more significant than those in the control group [Pplat (cmH2O, 1 cmH2O = 0.098 kPa):15.6±4.0 vs. 21.2±5.6, PIP (cmH2O): 18.3±5.0 vs. 25.1±5.4, Cst (mL/cmH2O): 41.2±4.8 vs. 31.2±6.0, PaO2 (mmHg, 1 mmHg = 0.133 kPa): 90.93±6.45 vs. 80.27±4.51, PaO2/FiO2 (mmHg): 238.33±18.31 vs. 185.83±11.14]. Heart rate [HR (bpm): 110.23±7.92 vs. 98.23±8.44] and the central venous pressure [CVP (mmHg): 8.62±1.52 vs. 6.32±1.42] were significantly higher than those before treatment, the mean arterial pressure [MAP (mmHg): 86.74±7.65 vs. 94.92±10.93] and cardiac output [CO (L/min): 5.32±1.36 vs. 6.42±1.32] were significantly reduced compared with those before treatment (all P < 0.05). The values of HR, MAP, CVP, CO at 5 minutes after recruitment were (97.87±5.77) bpm, (94.54±6.87) mmHg, (6.33±1.44) mmHg, (6.32±1.41) L/min, respectively. The changes of these parameters were not significant when compared with those of the basal conditions (P > 0.05) Conclusions Based on the lung protective ventilation in the early stage, sequential RM is applied in treatment of patients with SAP complicated with ARDS, after the IAP is essentially returned to a normal, which is beneficial to improving lung compliance, promoting oxygenation, shortening the time of mechanical ventilation, reducing the length of ICU stay, and decreasing the incidence of VAP without any obvious hemodynamic influence.

A clinical study of lung protective ventilation and sequential lung recruitment maneuver for treatment of severe acute pancreatitis complicated with acute respiratory distress syndrome / 中国中西医结合急救杂志

Objective To investigate the clinical therapeutic effects of lung protective ventilation and sequential recruitment maneuver (RM) on treatment of patients with severe acute pancreatitis (SAP) complicated with acute respiratory distress syndrome (ARDS). Methods Sixty patients with SAP complicated with ARDS admitted to the Department of Critical Care Medicine of the First Affiliated Hospital of Nanchang University from April 2014 to March 2016 were enrolled. They were divided into control group and experimental group by random number table, 30 patients in each group. On the basis of comprehensive treatment, the patients in control group were treated with lung protective ventilation mode: low tidal volume ventilation (6 mL/kg) + optimal end-expiratory positive pressure (PEEP) ventilation mode, when the intra-abdominal pressure (IAP) was essentially returned to a normal level (Ⅰ grade intra-abdominal hypertension), the patients in experimental group were treated by the combination with RM therapy, and the rest treatment was the same as the control group. Under the two types of ventilation strategies, the clinical effects, respiratory mechanics, hemodynamics and arterial blood gas indexes were compared between the two groups. Results The mechanical ventilation time (days: 13.82±4.40 vs. 19.87±7.40), the length of ICU stay (days:22.67±4.40 vs. 26.43±5.39) and incidence of ventilator associated pneumonia [VAP: 16.67% (5/30) vs. 26.67% (8/30)] of the experimental group were lower than those of the control group (all P < 0.05), the mortality rate of the experimental group was slightly lower than that of the control group [26.67% (8/30) vs. 30.00% (9/30)] without statistical significance (P > 0.05). Plateau pressure (Pplat) and the peak airway pressure (PIP) at each time point were decreased after treatment in both groups, while the static lung compliance (Cst), the arterial partial pressure of oxygen (PaO2) and oxygenation index (PaO2/FiO2) were increased compared with those before treatment, especially the changes at 72 hours after recruitment in the experimental group were more significant than those in the control group [Pplat (cmH2O, 1 cmH2O = 0.098 kPa):15.6±4.0 vs. 21.2±5.6, PIP (cmH2O): 18.3±5.0 vs. 25.1±5.4, Cst (mL/cmH2O): 41.2±4.8 vs. 31.2±6.0, PaO2 (mmHg, 1 mmHg = 0.133 kPa): 90.93±6.45 vs. 80.27±4.51, PaO2/FiO2 (mmHg): 238.33±18.31 vs. 185.83±11.14]. Heart rate [HR (bpm): 110.23±7.92 vs. 98.23±8.44] and the central venous pressure [CVP (mmHg): 8.62±1.52 vs. 6.32±1.42] were significantly higher than those before treatment, the mean arterial pressure [MAP (mmHg): 86.74±7.65 vs. 94.92±10.93] and cardiac output [CO (L/min): 5.32±1.36 vs. 6.42±1.32] were significantly reduced compared with those before treatment (all P < 0.05). The values of HR, MAP, CVP, CO at 5 minutes after recruitment were (97.87±5.77) bpm, (94.54±6.87) mmHg, (6.33±1.44) mmHg, (6.32±1.41) L/min, respectively. The changes of these parameters were not significant when compared with those of the basal conditions (P > 0.05) Conclusions Based on the lung protective ventilation in the early stage, sequential RM is applied in treatment of patients with SAP complicated with ARDS, after the IAP is essentially returned to a normal, which is beneficial to improving lung compliance, promoting oxygenation, shortening the time of mechanical ventilation, reducing the length of ICU stay, and decreasing the incidence of VAP without any obvious hemodynamic influence.