Pressure Ventilation Research Articles

Interpretation and use of intraoperative protective ventilation parameters: a scoping review.

Thirty years ago, the traditional approach to mechanical ventilation consisted of the normalization of PaCO2 and pH at the expense of using a tidal volume (VT) of 10-15 mL kg-1. But then, the use of 6-8 mL kg-1 became a dogma for ventilating patients either with acute respiratory distress syndrome (ARDS) or without lung disease in the operating theatre. It is currently recognized that even low tidal volumes may be excessive for some patients and insufficient for others, depending on its distribution in the aerated lung parenchyma. To carry out intraoperative protective mechanical ventilation, medical literature has focused on positive end expiratory pressure (PEEP), plateau pressure (Paw plateau), and airway driving pressure (ΔPaw). However, considering its limitations, other parameters have emerged that represent a better reflection of isolated lung stress, such as transpulmonary pressure (PL) and transpulmonary driving pressure (ΔPL). These parameters are less generalized in clinical practice due to the requirement of an oeso-phageal balloon for their measurement and therefore their cumbersome application in the operating theatre. However, its study helps in the interpretation of the rest of the ventilator pressures to optimize intraoperative mechanical ventilation. This article defines and develops protective ventilation parameters, breaks down their determinants, mentions their limitations, and offers recommendations for their use intraoperatively.

Season-oriented mine ventilation modes analysis

The paper presents the results of the data analysis conducted at Bereznyaki Mine-2 of Uralkali in summer and winter (during the air pre-treatment period). The findings show that when mine air heaters are operating thermal drop of ventilation pressure appears in air supply shafts. It causes “airlocks” in the shafts – a phenomenon that nearly stops the airflow in one of the shafts while increasing dramatically the airflow in the other (others) air intake shafts. As a result, mine air heaters in the shafts may stop running which provokes freezing of the mine shaft shoring. The analysis of mine ventilation modes performed in summer and winter determined the factors affecting the occurrence of “airlocks” in the air supply shafts during air pre-treatment. The reported study was supported by the Government of Perm Krai, research project of the International Research Group «Development of a digital model for forecasting and pricedependent demand response for electricity consumed by underground mining enterprises» (contract No. 26/506).

Механічна вентиляція легень, керована об’ємом або тиском під час нейрохірургічних операцій. Чи є перевага?

Актуальність. Однією з головних технологій сучасної анестезіології є механічна вентиляція легень (МВЛ). На даний час в інтенсивній терапії широко визнаною є протективна технологія МВЛ. Доцільність застосування даної технології в операційній, особливо у хворих з інтактними легенями, є не такою очевидною. Більшість наукових робіт, що висвітлюють дану проблему, стосується хворих з абдомінальною патологією, і менш висвітленою вона залишається у пацієнтів з нейрохірургічною патологією. Пацієнти, які оперуються з приводу нейрохірургічної патології, відносяться до групи хворих високого хірургічного ризику, це і змотивувало нас провести дане дослідження. Метою дослідження було вивчити доцільність застосування протективної МВЛ під час операційних втручань у нейрохірургічних хворих. Матеріали та методи. Нами обстежено 46 хворих, які знаходилися на стаціонарному лікуванні у КНП «8 МКЛ м. Львова» з приводу патології хребта та яким було виконане операційне втручання — вертебропластика із спондилодезом. Пацієнти були розподілені на дві групи: у першій групі (34 хворі) МВЛ проводили за технологією S-IPPV — синхронізована примусова вентиляція легень з контролем по об’єму, а в другій групі (12 хворих) МВЛ проводилась за технологією PCV — вентиляція, керована тиском. Результати. Ми ретроспективно визначили частоту виникнення післяопераційних легеневих ускладнень (ПОЛУ) у хворих першої та другої групи. З 34 хворих першої групи ознаки ПОЛУ були виявлені у 17 осіб (50 %), а з 12 хворих другої групи ПОЛУ було виявлено у 4 (33,3 %). Слід зауважити, що МВЛ у хворих обох груп не відрізнялася за такими параметрами, як частота дихання, кінцево-альвеолярний тиск на видиху та фракція кисню в дихальній суміші. Висновки. Порівняно невелика кількість хворих не дозволяє, очевидно, робити остаточні висновки, проте слід звернути увагу на те, що МВЛ (особливо керована об’ємом) сприяє виникненню післяопераційних легеневих ускладнень у пацієнтів з інтактними легенями в доопераційний період. А застосування МВЛ, керованої тиском, має тенденцію до зменшення частоти виявлення легеневих ускладнень в післяопераційному періоді. Якщо врахувати, що частота дихання, кінцево-альвеолярний тиск на видиху та фракція кисню в дихальній суміші були порівнянні у хворих обох груп, можна припустити, що фактором, який впливає на частоту виникнення ПОЛУ, є механіка вентиляції легень.

Investigating the control of exercise hyperpnoea: A synergy of contributions.

Investigating the control of exercise hyperpnoea: A synergy of contributions.

Sequential Organ Failure Assessment Outperforms Quantitative Chest CT Imaging Parameters for Mortality Prediction in COVID-19 ARDS.

(1) Background: Respiratory insufficiency with acute respiratory distress syndrome (ARDS) and multi-organ dysfunction leads to high mortality in COVID-19 patients. In times of limited intensive care unit (ICU) resources, chest CTs became an important tool for the assessment of lung involvement and for patient triage despite uncertainties about the predictive diagnostic value. This study evaluated chest CT-based imaging parameters for their potential to predict in-hospital mortality compared to clinical scores. (2) Methods: 89 COVID-19 ICU ARDS patients requiring mechanical ventilation or continuous positive airway pressure mask ventilation were included in this single center retrospective study. AI-based lung injury assessment and measurements indicating pulmonary hypertension (PA-to-AA ratio) on admission CT, oxygenation indices, lung compliance and sequential organ failure assessment (SOFA) scores on ICU admission were assessed for their diagnostic performance to predict in-hospital mortality. (3) Results: CT severity scores and PA-to-AA ratios were not significantly associated with in-hospital mortality, whereas the SOFA score showed a significant association (p < 0.001). In ROC analysis, the SOFA score resulted in an area under the curve (AUC) for in-hospital mortality of 0.74 (95%-CI 0.63–0.85), whereas CT severity scores (0.53, 95%-CI 0.40–0.67) and PA-to-AA ratios (0.46, 95%-CI 0.34–0.58) did not yield sufficient AUCs. These results were consistent for the subgroup of more critically ill patients with moderate and severe ARDS on admission (oxygenation index <200, n = 53) with an AUC for SOFA score of 0.77 (95%-CI 0.64–0.89), compared to 0.55 (95%-CI 0.39–0.72) for CT severity scores and 0.51 (95%-CI 0.35–0.67) for PA-to-AA ratios. (4) Conclusions: Severe COVID-19 disease is not limited to lung (vessel) injury but leads to a multi-organ involvement. The findings of this study suggest that risk stratification should not solely be based on chest CT parameters but needs to include multi-organ failure assessment for COVID-19 ICU ARDS patients for optimized future patient management and resource allocation.

Portal Vein Pulsatility as a Dynamic Marker of Venous Congestion Following Cardiac Surgery: An Interventional Study Using Positive End-Expiratory Pressure.

We aimed to assess variations in the portal vein pulsatility index (PI) during mechanical ventilation following cardiac surgery. Method. After ethical approval, we conducted a prospective monocentric study at Amiens University Hospital. Patients under mechanical ventilation following cardiac surgery were enrolled. Doppler evaluation of the portal vein (PV) was performed by transthoracic echography. The maximum velocity (VMAX) and minimum velocity (VMIN) of the PV were measured in pulsed Doppler mode. The PI was calculated using the following formula (VMAX − VMIN)/(VMax). A positive end-expiratory pressure (PEEP) incremental trial was performed from 0 to 15 cmH2O, with increments of 5 cmH2O. The PI (%) was assessed at baseline and PEEP 5, 10, and 15 cmH2O. Echocardiographic and hemodynamic parameters were recorded. Results. In total, 144 patients were screened from February 2018 to March 2019 and 29 were enrolled. Central venous pressure significantly increased for each PEEP increment. Stroke volumes were significantly lower after PEEP incrementation, with 52 mL (50–55) at PEEP 0 cmH2O and 30 mL (25–45) at PEEP 15 cmH2O, (p < 0.0001). The PI significantly increased with PEEP incrementation, from 9% (5–15) at PEEP 0 cmH2O to 15% (5–22) at PEEP 5 cmH2O, 34% (23–44) at PEEP 10 cmH2O, and 45% (25–49) at PEEP 15 cmH2O (p < 0.001). Conclusion. In the present study, PI appears to be a dynamic marker of the interaction between mechanical ventilation and right heart pressure after cardiac surgery. The PI could be a useful noninvasive tool to monitor venous congestion associated with mechanical ventilation.

Intraoperative Ventilatory Pressures During Robotic Assisted vs Open Radical Cystectomy

ObjectiveTo investigate whether Robotic assisted radical cystectomy (RARC) is associated with increased postoperative pulmonary complications compared to open radical cystectomy (ORC). RARC poses challenges for ventilation with positioning and abdominal insufflation. Conventionally protective mechanical ventilation may be challenging, especially in patients with obesity or pulmonary comorbidities. Given the proven benefits of RARC compared to ORC, the risk of postoperative pulmonary complications merits further investigation. Materials and methodsAdult patients consented for research who underwent RARC and ORC for invasive bladder cancer from 2013-2018 were identified for retrospective chart review. Perioperative and patient variables were looked at along with postoperative course and outcomes. Results328 patients who underwent ORC and 108 patients who underwent RARC were identified. Despite findings of higher peak airway pressures throughout surgery, patients who underwent RARC did not have a higher rate of pulmonary complications than patients who underwent ORC. Patients with obstructive sleep apnea (OSA) who underwent ORC had a higher rate of postoperative pulmonary complications. Patients who underwent RARC had a less intraoperative fluid administration, fewer ICU admissions, and decreased length of hospital stay. ConclusionDespite mechanical ventilation challenges, RARC was not associated with increased post-operative pulmonary complications compared to ORC. This was also found in patients with BMI>30 or with diagnosis or high suspicion of OSA. These findings suggest ventilation at higher pressures does not increase risk for ventilator induced lung injury in patients undergoing RARC, even in conventionally higher risk patients.

Awake prone position reduces work of breathing in patients with COVID-19 ARDS supported by CPAP

BackgroundThe use of awake prone position concomitant to non-invasive mechanical ventilation in acute respiratory distress syndrome (ARDS) secondary to COVID-19 has shown to improve gas exchange, whereas its effect on the work of breathing remain unclear. The objective of this study was to evaluate the effects of awake prone position during helmet continuous positive airway pressure (CPAP) ventilation on inspiratory effort, gas exchange and comfort of breathing.MethodsForty consecutive patients presenting with ARDS due to COVID-19 were prospectively enrolled. Gas exchange, esophageal pressure swing (ΔPes), dynamic transpulmonary pressure (dTPP), modified pressure time product (mPTP), work of breathing (WOB) and comfort of breathing, were recorded on supine position and after 3 h on prone position.ResultsThe median applied PEEP with helmet CPAP was 10 [8–10] cmH2O. The PaO2/FiO2 was higher in prone compared to supine position (Supine: 166 [136–224] mmHg, Prone: 314 [232–398] mmHg, p < 0.001). Respiratory rate and minute ventilation decreased from supine to prone position from 20 [17–24] to 17 [15–19] b/min (p < 0.001) and from 8.6 [7.3–10.6] to 7.7 [6.6–8.6] L/min (p < 0.001), respectively. Prone position did not reduce ΔPes (Supine: − 7 [− 9 to − 5] cmH2O, Prone: − 6 [− 9 to − 5] cmH2O, p = 0.31) and dTPP (Supine: 17 [14–19] cmH2O, Prone: 16 [14–18] cmH2O, p = 0.34). Conversely, mPTP and WOB decreased from 152 [104–197] to 118 [90–150] cmH2O/min (p < 0.001) and from 146 [120–185] to 114 [95–151] cmH2O L/min (p < 0.001), respectively. Twenty-six (65%) patients experienced a reduction in WOB of more than 10%. The overall sensation of dyspnea was lower in prone position (p = 0.005).ConclusionsAwake prone position with helmet CPAP enables a reduction in the work of breathing and an improvement in oxygenation in COVID-19-associated ARDS.

Ensuring optimal ventilation of calf buildings

Background: There has been considerable change over the past 10 years in the perceived value of beef and dairy calves, with potential for improvement to animal health and farm financial sustainability. One of the main calf health issues is respiratory disease, with multifactorial aspects that all require attention in order to produce healthy calves. Poor ventilation is often cited as a contributing factor to respiratory problems on specific farms, but it is seldom described in an objective manner that would facilitate providing an effective solution.Aim of the article: This article outlines the importance of fresh air in calf houses on calf health, with specific focus on natural ventilation, stack effect and positive pressure tube ventilation.

Long-Term Effects of Prematurity on Resting Ventilatory Response to Hypercapnia.

Manferdelli, Giorgio, Benjamin J. Narang, Mathias Poussel, Damjan Osredkar, Grégoire P. Millet, and Tadej Debevec. Long-term effects of prematurity on resting ventilatory response to hypercapnia. High Alt Med Biol. 22:420-425, 2021. Background: This study investigated the resting ventilatory response to hypercapnia in prematurely born adults. Materials and Methods: Seventeen preterm and fourteen full-term adults were exposed to normoxic hypercapnia (two 5-minute periods at 3% and 6% carbon dioxide [CO2] interspersed by 5-minute in normoxia). Pulmonary ventilation ([Formula: see text]) and end-tidal partial pressure of CO2 (Petco2) were measured continuously. Results: No difference in lung function was observed between preterm and full-term adults. Petco2 was lower in preterm than in full-term adults (p < 0.05) during normoxia. During exposure to 3% CO2, both [Formula: see text] and Petco2 increased in a similar way in preterm and full-term adults. However, at the end of the 6% CO2 period, there was a significantly higher [Formula: see text] in preterm compared with full-term adults (30.2 ± 7.5 vs. 23.7 ± 4.5 L/min, p < 0.0001), whereas no difference was observed for Petco2 (46.9 ± 2.1 vs. 50.6 ± 2.1 L/min, p = 0.99). Breath frequency was higher in preterm than in full-term adults (17.9 ± 4.0 vs. 12.8 ± 3.5 b/min, p < 0.01) during 6% CO2 exposure. Conclusions: Although data suggest that prematurity results in resting hypocapnia, the exact underlying mechanisms remain to be elucidated. Moreover, preterm adults seem to have increased chemosensitivity to hypercapnia.

Aerosol delivery through high flow nasal cannula compared to biphasic positive airway pressure, at two different pressure: an in-vitro study

BackgroundBoth non-invasive ventilation and high flow oxygen therapy are preferred over low flow oxygen therapy in many conditions. Nebulizers, for aerosol delivery, can be used within them without interrupting the circuit. The present study aimed to compare the efficiency of drug delivery within high flow nasal cannula (HFNC) and biphasic positive airway pressure (BiPAP) ventilation mode using two different inspiratory positive airway pressures. The aerosol delivery was examined in HFNC system at low flow, 5 L min−1, and BiPAP non-invasive ventilation under 2 different pressures [high pressure; inspiratory positive airway pressure/expiratory positive airway pressure (IPAP/EPAP) of 20/5 cm water, and low pressure; IPAP/EPAP of 10/5 cm water]. The total inhalable dose (TID) was measured by inserting an Aerogen Solo nebulizer installed with 1 mL salbutamol respiratory solution (5000 μg mL−1) within the circuit, and the salbutamol was collected on an inhalation filter placed in a filter holder connected to a breathing simulator. The breathing simulator was adjusted at a tidal volume of 500 mL, respiratory rate of 15 breaths min−1, and inhalation to exhalation (I:E) ratio of 1:1 for the adult setting. In each technique of the three (HFNC, and low, and high-pressures BiPAP), TID was determined 5 times (n = 5). For particle size characterization, cooled Anderson Cascade Impactor (ACI) was inserted instead of the inhalation filter and the breathing simulator with the same scheme. In each technique of the three, particle size characterization was determined 3 times (n = 3).ResultsThe BiPAP mode at low inspiratory pressure had the highest TID, followed by HFNC at flow 5 L min−1, then BiPAP mode at high inspiratory pressure. There was a significant difference only between low and high inspiratory pressure modes of BiPAP mode. Low-inspiratory pressure BiPAP delivered the highest mean ± SD fine particle dose (FPD). It was significantly higher than that delivered in high inspiratory pressure BiPAP, and HFNC. Also, FPD in HFNC was significantly higher than that in high inspiratory pressure BiPAP. HFNC system had the smallest mass median aerodynamic diameter (MMAD) and the highest FPF followed by low then high inspiratory pressure BiPAP.ConclusionsIncreasing the inspiratory positive airway pressure in BiPAP, from 10 to 20 cm water, decreased the total inhalable dose and FPF nearly by half. Low inspiratory pressure BiPAP delivered the highest TID and FPD. The HFNC system at low oxygen flow resulted in the least MMAD, and the highest FPF. Using HFNC delivered a TID that was non-significant from that delivered by low inspiratory pressure BiPAP.Graphical

Effects of electrical muscle stimulation on cerebral blood flow

BackgroundElectrical muscle stimulation (EMS) induces involuntary muscle contraction. Several studies have suggested that EMS has the potential to be an alternative method of voluntary exercise; however, its effects on cerebral blood flow (CBF) when applied to large lower limb muscles are poorly understood. Thus, the purpose of this study was to examine the effects of EMS on CBF, focusing on whether the effects differ between the internal carotid (ICA) and vertebral (VA) arteries.MethodsThe participants performed the experiments under EMS and control (rest) conditions in a randomized crossover design. The ICA and VA blood flow were measured before and during EMS or control. Heart rate, blood pressure, minute ventilation, oxygen uptake, and end-tidal partial pressure of carbon dioxide (PETCO2) were monitored and measured as well.ResultsThe ICA blood flow increased during EMS [Pre: 330 ± 69 mL min−1; EMS: 371 ± 81 mL min−1, P = 0.001, effect size (Cohen’s d) = 0.55]. In contrast, the VA blood flow did not change during EMS (Pre: 125 ± 47 mL min−1; EMS: 130 ± 45 mL min−1, P = 0.26, effect size = 0.12). In the EMS condition, there was a significant positive linear correlation between ΔPETCO2 and ΔICA blood flow (R = 0.74, P = 0.02). No relationships were observed between ΔPETCO2 and ΔVA blood flow (linear: R = − 0.17, P = 0.66; quadratic: R = 0.43, P = 0.55).ConclusionsThe present results indicate that EMS increased ICA blood flow but not VA blood flow, suggesting that the effects of EMS on cerebral perfusion differ between anterior and posterior cerebral circulation, primarily due to the differences in cerebrovascular response to CO2.

Observation on the Curative Effect of Non-invasive Positive Pressure Ventilation Pressure Sore Nursing Intervention for Critically Ill Patients with COPD

Observation on the Curative Effect of Non-invasive Positive Pressure Ventilation Pressure Sore Nursing Intervention for Critically Ill Patients with COPD

Challenge of surviving COPD with COVID-19 patient: review of the literature with unusual case report

Chronic obstructive pulmonary disease (COPD) refers to limitation of air flow and presence of persistent respiratory symptoms due to abnormalities in the airway or alveolar airway. COVID-19 patients with COPD have a higher mortality and morbidity. Recent studies revealed that present smokers have a higher risk mortality rate than the former and never smokers. However, COPD patients infected with SARS-CoV-2 have a low survival rate during the COVID-19 pandemic. Here we present a case of COVID-19 in a patient with COPD. The patient presented with shortness of breath, altered mental status, and loss of consciousness and 3 days prior was diagnosed with COVID-19, by reverse transcription polymerase chain reaction. The patient diagnosed by physical, and laboratory findings, and treated by giving 2 L/min oxygen on a ventilator pressure control ventilation mode, with administered antibiotic, antipyretic, proton pump inhibitors, and mucolytic drugs without complications. COVID-19 incidence is increased when there are other illnesses present, such as COPD. Based on 18 studies of 26,075 cases reporting, COPD was significantly associated with an increased risk of adverse outcomes in COVID-19 patients, particularly current smokers. We report a case of COVID-19, heavy smoker with a 1-year history of COPD with a positive outcome. The patient suffered from severe respiratory failure, requiring the use of ventilation gave 2 L/min oxygen on pressure control ventilation mode. Our findings suggest that the development of COVID-19, which could lead to death, needs critical assessment and special consideration for COPD patients and existing smokers.

Twenty-four-hour mechanical power variation rate is associated with mortality among critically ill patients with acute respiratory failure: a retrospective cohort study

ObjectivesDefined as the energy applied to the respiratory system by ventilator, mechanical power (MP) of ventilation reflects the risk of ventilation-induced lung injury. This study aims to explore the relationship between dynamic changes in MP and prognosis in critically ill patients.MethodsThis was a single-centre retrospective cohort study. Patients receiving mechanical ventilation with acute respiratory failure (ARF) and MP > 10 J/min on admission in the ICU were included. MP (J/min) was calculated as 0.098 × minute ventilation (L/min) × [(peak inspiratory pressure + positive end-expiratory pressure)/2] and the MP variation rate (%) as ([baseline MP − 24-h MP]/baseline MP) × 100. Patients were divided into two groups according to whether MP decreased 24 h after admission (MP-improved group defined as 24-h MP variation rate > 0% vs. MP-worsened group defined as 24-h MP variation rate ≤ 0%).ResultsIn total, 14,463 patients were screened between January 2015 and June 2020, and finally, a study cohort of 602 patients was obtained. The MP-improved group had a lower ICU mortality rate than the MP-worsened group (24% vs. 36%; p = 0.005). The 24-h MP variation rate was associated with ICU mortality after adjusting for confounders (odds ratio, 0.906 [95% CI 0.833–0.985]; p = 0.021), while baseline MP (p = 0.909) and 24-h MP (p = 0.059) were not. All MP components improved in the MP-improved group, while minute ventilation and positive end-expiratory pressure contributed to the increase in MP in the MP-worsened group.ConclusionsThe 24-h MP variation rate was an independent risk factor for ICU mortality among ARF patients with elevated MP. Early decreases in MP may provide prognostic benefits in this population.

The role of intraoperative pulmonary arterial catheterization data in determining the need for extracorporeal membrane oxygenation in lung transplantation.

Background This study aims to investigate predictive factors of identification of the need of patients for extracorporeal membrane oxygenation support during lung transplantation. Methods A total of 63 patients (49 males, 14 females, mean age: 44.9±14.4 years; range, 14 to 64 years) who underwent lung transplantation in our institution between December 2016 and December 2019 were retrospectively analyzed. Demographic characteristics and perioperative clinical data of patients were recorded. After induction and pulmonary artery catheterization, cardiac output, mean pulmonary artery pressure, pulmonary capillary wedge pressure, cardiac index, pulmonary vascular resistance, systemic vascular resistance, and right atrial pressure were measured using the thermodilution technique. Results Thirty-three of the patients received extracorporeal membrane oxygenation support during surgery. The right atrial pressure (p<0.001), pulmonary capillary wedge pressure (p<0.002), mean pulmonary artery pressure (p<0.001), and pulmonary vascular resistance (p<0.001) were statistically significantly higher in the patients who required extracorporeal membrane oxygenation support intraoperatively. The systemic vascular resistance (p<0.032) was statistically significantly lower in the patients who required extracorporeal membrane oxygenation support intraoperatively. A mean pulmonary artery pressure of >39 mmHg (p<0.02) and a right atrial pressure of >12 mmHg (p<0.047) were independent risk factors for ECMO support intraoperatively during lung transplantation. Conclusion Predicting the need of intraoperative extracorporeal membrane oxygenation support is of utmost importance in timing the need for mechanical support, protecting the new graft from high mechanical ventilator pressures, and adequately maintaining hemodynamic stability.

Преоксигенация: терминология, физиологические основы, техники проведения, методики повышения эффективности, особенности у критических пациентов, возможные риски

Преоксигенация является широко распространенным приемом перед индукцией в анестезию и интубацией трахеи, предназначенным для увеличения запасов кислорода в организме и, таким образом, замедления начала десатурации гемоглобина во время апноэ. Показателями эффективности преоксигенации являются увеличение фракции альвеолярного кислорода, увеличение напряжения кислорода в артериальной крови и снижение фракции альвеолярного азота. Конечная точка максимальной преоксигенации — концентрация кислорода в конце выдоха 90 % или концентрация азота в конце выдоха 5 %. Для проведения преоксигенации используются две техники: по дыхательному объему и путем глубоких вдохов. Существуют различные методики для улучшения эффекта преоксигенации. Они включают поднятие головы, апнойную диффузную оксигенацию, использование постоянного положительного давления/положительного давления конца выдоха, двухуровневое положительное давление в дыхательных путях и трансназальную увлажненную быструю инсуффляцию. Преоксигенация с высоким риском включает таких пациентов, как беременные женщины, пациенты, страдающие ожирением, дети, лица пожилого возраста, пациенты с сопутствующими легочными заболеваниями, пациенты на большой высоте. Потенциальные риски преоксигенации включают отсроченное определение пищеводной интубации, абсорбционный ателектаз, продукцию частиц активного кислорода и нежелательные гемодинамические эффекты. Так как преоксигенация по времени не продолжительна, гемодинамические эффекты и накопление частиц активного кислорода незначительны. Абсорбционный ателектаз является следствием преоксигенации. Для снижения риска возникновения абсорбционного ателектаза во время преоксигенации предложено два подхода: умеренное снижение фракции кислорода до 0,8 и использование рекрутмент-маневров, таких как постоянное положительное давление, положительное давление конца выдоха и/или маневры с жизненной емкостью легких. Хотя незначительное давление фракции кислорода уменьшает риск ателектазирования, это происходит за счет снижения кислородного резерва. Техника преоксигенации должна использоваться правильно, с мониторированием концентрации кислорода в конце выдоха. Анестезиолог должен быть ознакомлен с различными методиками проведения преоксигенации, выбирая наиболее подходящую.

Тривалість штучної вентиляції легень та функціонування діафрагми у дітей з гострою дихальною недостатністю

Актуальність. Пацієнти з комбінованими формами дихальної недостатності часто мають довготривале чи навіть невдале відлучення від штучної вентиляції легень (ШВЛ). Мета дослідження: порівняти тривалість проведення ШВЛ, а також показники функціонування діафрагми при використанні технологій P-SIMV та BIPAP у пацієнтів на етапі відлучення від ШВЛ. Матеріали та методи. Проведено проспективне обсерваційне нерандомізоване когортне дослідження серед 27 пацієнтів з гострою дихальною недостатністю. До І (режим P-SIMV) та ІІ груп пацієнтів (режим BIPAP ) увійшло по 10 пацієнтів. Первинними точками оцінювання результатів лікування були тривалість проведення інвазивної ШВЛ; вторинними точками — амплітуда рухів обох куполів діафрагми, фракція стоншення діафрагми, виникнення декомпенсованого респіраторного чи змішаного ацидозу. Результати. Середня тривалість проведення ШВЛ у пацієнтів першої групи становила 14,14 ± 1,83 доби, у пацієнтів другої групи — 13,2 ± 2,56 доби (p = 0,32). Амплітуда рухів куполів діафрагми в першу добу дослідження становила в І групі пацієнтів 7,2 ± 1,8 мм, у ІІ групі — 6,8 ± 1,5 (p = 0,42); на 5-ту добу лікування цей показник вірогідно не відрізнявся між групами та в І групі зростав до 8,1 ± 2,1 мм, у ІІ — до 8,4 ± 1,9 мм (p = 0,12 та p = 0,89). Вже на 9-ту добу лікування амплітуда рухів правого купола діафрагми вірогідно (р = 0,04) відрізнялася у І групі пацієнтів щодо ІІ групи (9,0 ± 2,1 мм та 10,0 ± 1,3 мм відповідно) та щодо попереднього етапу обстеження (p = 0,05 та p = 0,04). Амплітуда рухів правого купола діафрагми залишалася на рівні понад 10 мм у ІІ групі пацієнтів і на 13-ту та 17-ту добу спостереження за пацієнтами. Висновки. Тривалість проведення ШВЛ у дітей з поєднанням обструктивного та рестриктивного типів дихальної недостатності в І та ІІ групах вірогідно не відрізнялася. Спонтанні дихальні зусилля були вірогідно вищими у пацієнтів ІІ групи починаючи з 9-ї доби порівняно з пацієнтами І групи.

Feasibility of open abdomen surgery treatment for near fatal necrotizing enterocolitis in preterm infants

IntroductionNecrotizing Enterocolitis (NEC) remained a dramatic complication leading to death or neonatal morbidities in preterms. For some, Intra-Abdominal Hypertension (IAH) and Abdominal Compartment Syndrome worsened the multi-organ failure. An open abdomen surgery could be an alternative to conventional surgical treatment to move beyond this stage. ObjectivesTo retrospectively describe the clinical course, pre- and post-operative features of preterms suffering from severe NEC with IAH treated by open abdomen surgery and referred to our center from October 2007 to September 2019. Our secondary objective is to identify various risk factors for mortality in this population. MethodsData on neonatal, clinical, biological, pre and post-operative features and outcome were collected. Univariate analyses were performed to compare their pre and post-operative features stratifying on outcome. ResultsAmong 29 included patients, 14 (48%) survived to discharge without short bowel syndrome. Death was associated with an earlier postnatal age at NEC (16.3 ± 9.1 versus 31.3 ± 25.9 days; p = 0.004) and followed a withdrawal of treatment in 60% of cases. Surgery was associated with a significant improvement of respiratory and hemodynamic features (decrease of mean ventilator pressure from 13.1 ± 5.4 to 11.3 ± 4.0 cmH2O, p < 0.001), oxygen requirement (mean FiO2 decreased from 65.0% ± 31.2 to 49.0% ± 24.6, p < 0.001) and inotropic score (from 38.6 ± 70.1 to 29.9 ± 64.3, p < 0.001). In the survival group, pre and post-operative findings exhibited a significant increase of serum lactate concentrations from 2.7 ± 1.6 to 11.0 ± 20.3 mmol/L (p = 0.02) but a similar pH. ConclusionOpen abdomen surgery could be considered to rescue preterms with near fatal NEC. IAH and Abdominal Compartment Syndrome in these preterms should be investigated through further studies. Level of evidenceLevel III

Management of Preterm Infants with Respiratory Distress Syndrome Using Non-Invasive High Frequency Ventilation versus Nasal Continuous Positive Airway Pressure

Background: Preterm infants have a risk of the respiratory distress syndrome (RDS). Helpful effects of high-frequency ventilators have been shown within management of RDS as well as the use of these ventilators as the initial mode of support or as a rescue treatment once failure of standard mechanical ventilation. Objective: This study aimed to compare between the nasal high-frequency oscillatory ventilation (nHFOV) and nasal continuous positive airway pressure (NCPAP) in the treatment of preterm infants with RDS in. Patients and methods: A study included 62 neonates with respiratory distress syndrome and was conducted at neonatal intensive care unit, Pediatrics Department, Zagazig University Hospital. Cases were divided into; group (A) was managed with non-invasive high frequency nasal ventilation and group (B) was managed with nasal continuous positive airway pressure. All cases were subjected to full medical history, clinical assessment, laboratory investigations and Silverman Score for respiratory distress grading. Results: There was statistically non-significant difference between the studied groups regarding occurrence of nasal injury, oxygen supply after study and need for use of surfactant. There was statistically non-significant difference between the studied groups regarding x ray findings before or by the end of the study. There was statistically significant relation between gestational age groups and need for surfactant in NHFV group. Conclusion: Noninvasive high frequency ventilation (NHFV) represent a better primary non-invasive mode than NCPAP in treatment of preterm infants with RDS.