Intermittent Mandatory Ventilation Research Articles

Evaluation of IntelliVent-ASV® and PS-SIMV Mode Using Ultrasound (US) Measurements in Terms of Diaphragm Atrophy.

Mechanical ventilation is a life-saving intervention for critically ill patients, but it can also lead to diaphragm atrophy, which may prolong the duration of mechanical ventilation and the length of stay in the intensive care unit. IntelliVent-ASV® (Hamilton Medical, Rhäzüns, Switzerland) is a new mode of ventilation that has been developed to reduce diaphragm atrophy by promoting spontaneous breathing efforts. In this study, we aimed to evaluate the effectiveness of IntelliVent-ASV® and pressure support-synchronized intermittent mandatory ventilation (PS-SIMV) mode in reducing diaphragm atrophy by measuring diaphragm thickness using ultrasound (US) imaging. We enrolled 60 patients who required mechanical ventilation due to respiratory failure and were randomized into two groups: IntelliVent-ASV®and PS-SIMV. We measured the diaphragm thickness using US imaging at admission and on the seventh day of mechanical ventilation. Our results showed that diaphragm thickness decreased significantly in the PS-SIMV group but remained unchanged in the IntelliVent-ASV®group. The difference in diaphragm thickness between the two groups was statistically significant on the seventh day of mechanical ventilation. IntelliVent-ASV®may reduce diaphragm atrophy by promoting spontaneous breathing efforts. Our study suggests that this new mode of ventilation may be a promising approach to preventing diaphragm atrophy in mechanically ventilated patients. Further studies using invasive measures of diaphragm function are warranted to confirm these findings.

Impact of pressure-targeted modes of ventilation on diaphragmatic function as assessed using ultrasonography in critically ill patients with cerebral insult: a randomized clinical trial

BackgroundMechanical ventilation causes diaphragmatic atrophy and reduces diaphragmatic efficiency. Patients with diaphragmatic dysfunction have longer mechanical ventilation durations and intensive care unit stay. There is currently a scarcity of data on the effect of different modes of mechanical ventilation on diaphragmatic function and ultrasound-guided assessment of diaphragmatic efficiency.ResultsSixty mechanically ventilated patients were randomly divided into four equal groups (15 each): patients were ventilated using either assist control pressure-controlled mode (group A), synchronized intermittent mandatory ventilation pressure-controlled mode (group S), bi-level-positive airway pressure mode (group B) or pressure support ventilation mode (group P). The primary outcome was to assess the diaphragmatic excursion, while the secondary outcomes were to assess the diaphragmatic thickness fraction and the duration of the ICU stay. Patients in the P group had the highest diaphragmatic excursion indicating better diaphragmatic function.ConclusionsWhen compared to other pressure-targeted ventilation modes, the pressure support ventilation mode may have the least risk of diaphragmatic dysfunction as preserves diaphragmatic structure and strength.Trial registrationThe clinical trial was retrospectively registered at http://www.pactr.org PACTR202112653971335.

The effect of APRV-LTV mechanical ventilation mode on SpO2 and ventilation indices in patients with COVID-19

Background & Aim: Mechanical ventilation is a life-saving method for acute respiratory distress syndrome. The present study aimed to investigate the impact of airway pressure release ventilation-low tidal volume mode on COVID-19 patients’ peripheral capillary oxygen saturation and ventilation indices.
 Methods & Materials: This clinical trial was conducted on 70 COVID-19 patients hospitalized in the Intensive care unit in Qom, Iran. Patients were selected using convenience sampling and randomly allocated to intervention and control groups. In the control group, patients were ventilated using synchronized intermittent mandatory ventilation mode, and in the intervention group, patients were ventilated using airway pressure release ventilation-low tidal volume mode. Patients’ peripheral capillary oxygen saturation and ventilation indices were checked and recorded before and after the intervention. The data were analyzed using SPSS 11.5.
 Results: According to the results of the repeated-measures ANOVA test before the intervention and the 2 and 4 hours after the intervention, there were no significant differences between the intervention and control groups regarding the fraction of inspired oxygen, volume minute per minute, and peripheral capillary oxygen saturation (P>0.05). However, in the intervention group compared to the control group, the mean of PIP was significantly reduced (P<0.05).
 Conclusion: In patients with COVID-19, the two modes of mechanical ventilation, APRV, and control, had no significant differences in the fraction of inspired oxygen, volume minute per minute, and peripheral capillary oxygen saturation. However, the mean peak inspiratory pressure reduction in the intervention group was greater than that in the control group. Considering that several factors can affect peripheral capillary oxygen saturation and ventilation indices, these results should be considered with caution.

PULM6: Exploratory In Vivo Testing Of A Non-Invasive Ventilation Assist Device

Background: Mechanical ventilation is normally accomplished by positive pressure, either invasively through an endotracheal tube, or non-invasively through a mask or nasal prongs. Positive pressure ventilation (PPV) is associated with ventilator induced lung injury (VILI), especially in infants. Negative pressure ventilation (NPV) is more physiologic and preferentially opens posterior areas of the sick lung refractory to opening with positive pressure ventilation alone. However, NPV is not widely used due to the cumbersome negative air pressure chambers requiring torso and neck seals. Methods: We have developed a more practical device for achieving NPV. The Torso Expander consists of flexible tubes attached to a base layer which adheres to the torso with a silicone skin adhesive. Positive air pressure applied to the tubes causes elongation of the tubes and a distending pressure on the torso. The distending pressure may be static or cycled on and off (Torso Assist Ventilation - TAV) at a manual rate, or synchronized to the patient’s respiration (spontaneous or ventilator induced). The Torso Expander, sized for infants, was tested acutely in 5 piglets (3.1+/- 0.2 kg) during normal physiologic states as well as simulated ARDS by saline lavage surfactant washout, and simulated neuromuscular dysfunction by rocuronium paralysis, in order to study the biomechanics and potential clinical applications with various testing modes. Results: In the ARDS model, when static inflation (up to 400 mmHg) was added to the synchronized intermittent mandatory ventilation (SIMV) for a period of 17 min, intra-abdominal pressure was reduced by 1.0-1.5 cm-water per 100 mmHg inflation pressure, average tidal volume (TV) was increased by 5ml, and average respiratory rate was decreased by 27/min compared to the baseline SIMV. Gastric pressure, which may be measured less invasively in clinical use, correlated linearly (r2 > 0.94) with intra-abdominal pressure. TAV, synchronized with spontaneous and ventilator breaths, was demonstrated, resulting in increases in TV. During static and TAV support oxygenation improved (PaO2/FiO2 increased from 69 to 222 mmHg on average after the interventions). TAV alone was able to support a TV of 5 ml/kg with the animal paralyzed. Discussion: Exploratory studies demonstrated the beneficial effects of this novel non-invasive method of NPV. Additional studies are underway to further quantify these observations and test the technology in adults. This technology may reduce the time on PPV, or avoid PPV in some cases.

Weaning in neurally adjusted ventilatory assist: a prospective interventional study in neonates.

Neurally adjusted ventilatory assist (NAVA) is a respiratory support triggered by the electrical activity of the diaphragm (EAdi). Only few studies evaluated NAVA short-term efficacy and safety in newborns. Aim of this study was to assess efficacy and safety of NAVA in a cohort of newborns and to analyze ventilation parameters helpful to guide weaning. Thirty-four newborns with respiratory failure were ventilated with synchronized intermittent mandatory ventilation plus pressure-regulated volume control plus pressure support (SIMV(PRVC)+PS) for 12 hours and switched to NAVA until extubation. Ventilator and vital parameters, oxygen saturation (SpO2)/fraction of inspired oxygen (FiO2) ratio (S/F), arterialized capillary blood gases (aCBG), and sedatives dose were recorded. The occurrence of reintubation within the first 72 hours, pneumothorax and mortality were evaluated. After 6 hours of NAVA, a significant reduction of FiO2 (0.25 versus 0.32), and peak inspiratory pressure (13 versus 18 mmHg), and a significant increase of S/F (383 versus 316) were found, compared to SIMV(PRVC)+PS. Other ventilation, vital and aCBG parameters were similar in both ventilation modes. During NAVA a significant reduction of sedation was shown. All subjects were successfully extubated guided by EAdi peak during weaning. No reintubation, pneumothorax, or death were recorded. NAVA can be effectively and safely used in neonates. The EAdi peak could be a reliable index to guide the physicians during weaning and extubation.

Effect of the change of mechanical ventilation mode on cerebral oxygen saturation level in neonates

BackgroundThis study aimed to apply near-infrared spectroscopy (NIRS) to monitor cerebral oxygen saturation (SrO2) level in neonates before and after the change of mechanical ventilation mode, and thus, the effects of the change of mechanical ventilator mode on SrO2 level in neonates were assessed.MethodsThis trial was designed as an observational study .A total of 70 neonates who were admitted to the Department of Neonatology of Beijing Luhe Hospital Affiliated to Capital Medical University (Beijing, China) between September 2019 and October 2021 and required respiratory support were included. The variations of SrO2 level before and after the change of mechanical ventilation mode, including changing from Synchronized intermittent mandatory ventilation (SIMV) to noninvasive ventilation (NIV, group 1), and from NIV to oxygen inhalation (group 2), were monitored by Enginmed EGOS-600 A. The changes of SrO2 level at 30 min before and 1 h after the change of ventilation mode were compared between the two groups.ResultsThe SrO2 level in the group 1 30 min before, as well as 10 min, 30 min, and 1 h after the change of ventilation mode was 62.54 ± 3.36%, 65.43 ± 3.98%, 64.38 ± 4.23%, and 64.63 ± 3.71%, respectively. The SrO2 level at all the points after the change of ventilation mode increased compared with 30 min before the change (P < 0.05). The SrO2 level in the group 2 at each time point was 62.67 ± 4.69%, 64.61 ± 5.00%, 64.04 ± 4.48%, and 64.55 ± 4.32%, respectively. Compared with 30 min before ventilator weaning, the SrO2 level at all the points after ventilator weaning increased (P < 0.05). Peak inspiratory pressure (PIP) excluding Nasal Continuous Positive Airway Pressure (NCPAP)) in group 1 was lower than that before extubation, and the difference was statistically significant (P = 0) (Table 7).ConclusionsSrO2 level showed an increasing trend after the change of ventilation mode, and the increase of SrO2 level at 10 min after the change of ventilation mode was the most prominent. From SIMV to NIV, increased SrO2 levels may be associated with decreased PIP.

Patient outcomes after neonatal tracheotomy: A retrospective case-control study.

Patient outcomes after neonatal tracheotomy: A retrospective case-control study.

Study protocol for a randomized controlled trial of Proportional Assist Ventilation for Minimizing the Duration of Mechanical Ventilation: the PROMIZING study

BackgroundProportional assist ventilation with load-adjustable gain factors (PAV+) is a mechanical ventilation mode that delivers assistance to breathe in proportion to the patient’s effort. The proportional assistance, called the gain, can be adjusted by the clinician to maintain the patient’s respiratory effort or workload within a normal range. Short-term and physiological benefits of this mode compared to pressure support ventilation (PSV) include better patient-ventilator synchrony and a more physiological response to changes in ventilatory demand.MethodsThe objective of this multi-centre randomized controlled trial (RCT) is to determine if, for patients with acute respiratory failure, ventilation with PAV+ will result in a shorter time to successful extubation than with PSV. This multi-centre open-label clinical trial plans to involve approximately 20 sites in several continents. Once eligibility is determined, patients must tolerate a short-term PSV trial and either (1) not meet general weaning criteria or (2) fail a 2-min Zero Continuous Positive Airway Pressure (CPAP) Trial using the rapid shallow breathing index, or (3) fail a spontaneous breathing trial (SBT), in this sequence. Then, participants in this study will be randomized to either PSV or PAV+ in a 1:1 ratio. PAV+ will be set according to a target of muscular pressure. The weaning process will be identical in the two arms. Time to liberation will be the primary outcome; ventilator-free days and other outcomes will be measured.DiscussionMeta-analyses comparing PAV+ to PSV suggest PAV+ may benefit patients and decrease healthcare costs but no powered study to date has targeted the difficult to wean patient population most likely to benefit from the intervention, or used consistent timing for the implementation of PAV+. Our enrolment strategy, primary outcome measure, and liberation approaches may be useful for studying mechanical ventilation and weaning and can offer important results for patients.Trial registrationClinicalTrials.gov NCT02447692. Prospectively registered on May 19, 2015.

Synchronized intermittent mandatory ventilation with volume guarantee and pressure support in neonates: Detailed analysis of ventilator parameters

To analyse the relationship between peak inflating pressure, expired tidal volume, respiratory rate, and inspiratory time of volume-guaranteed ventilator inflations and pressure-supported spontaneous breaths during synchronized intermittent positive pressure mode with volume guarantee and pressure support (SIMV-VG-PS) in neonates. Ventilator parameters were downloaded every second from 16 babies ventilated with SIMV-VG-PS mode using Dräger Babylog VN500 ventilators over 137 days. Transcutaneous carbon dioxide (tcCO2 ) data were also collected. Data were computationally analysed using Python. The average of each ventilator parameter was determined during each minute separately for ventilator inflations and for spontaneous breaths. These values were compared and their effect on tcCO2 levels was also analysed. The relationship between the peak inflating pressure of the volume guaranteed inflations (PIPVG ) and pressure-supported spontaneous breaths (PIPPS ) was highly variable. The PIPPS /PIPVG ratio differed significantly from the value (0.66) targeted by clinicians (group median: 0.80, range: 0.50-1.00). PIPPS frequently exceeded PIPVG . When PIPPS /PIPVG was >0.66, the expired tidal volume and the rate of the pressure-supported spontaneous breaths were also significantly (p < 0.0001) higher, but there was no difference in tcCO2 levels. The flow-cycled spontaneous breaths had significantly shorter inspiratory times than ventilator inflations. During SIMV-VG-PS it is difficult to ensure a pressure support level proportionate to the inflating pressure of ventilator inflations and to achieve the stability of tidal volumes.

Newborns born to mothers with a history of COVID-19 during pregnancy, delivery and/or postpartum: 52 cases of neonatal intensive care experience

Objective: The effect of the Covid-19 pandemic on the prenatal and neonatal periods is not yet fully understood. Therefore, this study aimed to prospectively evaluate and investigate the clinical features of newborns who were born to mothers with a history of Covid-19 during pregnancy, delivery, and/or postpartum. Patient and Methods: The study prospectively evaluated 52 newborns born to mothers with a history of Covid-19 during pregnancy, delivery, and/or postpartum followed in our hospital's neonatal intensive care unit between November 2020 and May 2022. Results: Unvaccinated mothers of 12 babies with Covid-19 IgG antibody positivity + severe pneumonia in their clinical course and/or chest X-ray stated that they did not have a history of Covid-19. It was found that attachment to intermittent mechanical ventilation (SIMV) in infants with a Covid-19 -infected father was statistically significantly higher than in infants with a non-infected father. The rate of being connected to synchronized intermittent mechanical ventilation (SIMV) in babies whose both parents had Covid-19 was statistically significantly higher than in the babies whose fathers did not have Covid-19 (p:0.030; p&lt;0.05). Conclusion: Newborns born to mothers suspected or confirmed to be Covid-19-positive are mostly asymptomatic, suspected cases or cases with a severe or unusual clinical course should be investigated for Covid-19 even if there is no maternal history. In newborns, not only the mother but also the father should be questioned for Covid-19, as both parents being infected will increase the viral load.

Respiratory physiology during NAVA ventilation in neonates born with a congenital diaphragmatic hernia: The "NAVA-diaph" pilot study.

Neurally adjusted ventilatory assist (NAVA) is a ventilatory mode that delivers synchronized ventilation, proportional to the electrical activity of the diaphragm (EAdi). Although it has been proposed in infants with a congenital diaphragmatic hernia (CDH), the diaphragmatic defect and the surgical repair could alter the physiology of the diaphragm. To evaluate, in a pilot study, the relationship between the respiratory drive (EAdi) and the respiratory effort in neonates with CDH during the postsurgical period under either NAVA ventilation or conventional ventilation (CV). This prospective physiological study included eight neonates admitted to a neonatal intensive care unit with a diagnosis of CDH. EAdi, esophageal, gastric, and transdiaphragmatic pressure, as well as clinical parameters, were recorded during NAVA and CV (synchronized intermittent mandatory pressure ventilation) in the postsurgical period. EAdi was detectable and there was a correlation between the ΔEAdi (maximal - minimal values) and the transdiaphragmatic pressure (r = 0.26, 95% confidence interval [CI] [0.222; 0.299]). There was no significant difference in terms of clinical or physiological parameters during NAVA compared to CV, including work of breathing. Respiratory drive and effort were correlated in infants with CDH and therefore NAVA is a suitable proportional mode in this population. EAdi can also be used to monitor the diaphragm for individualized support.

Intellectual ventilation modes in Russian Federation: a short questionnaire survey

INTRODUCTION: There are a lot of clinical trials about benefits of closed-loop ventilation modes, which are able to automatically adjust certain respiratory settings. These studies describe safety, reliability and advantages of intellectual modes over conventional ventilation modes. OBJECTIVE: To assess awareness of Russian intensive care practitioners about closed loop ventilation modes and availability of these modes in routine practice. The second aim was to explore difficulties and problems that arise for practitioners during work with these modes. MATERIALS AND METHODS: A short survey conducted with online and offline questionnaire. The survey consisted of nine questions regarding the application of closed-loop modes, some question has open answers. RESULTS: The response rate of the survey was 33 % (248 of 750). Most of respondents (85 %) have heard about closed-loop modes, and 52 % had access to these technologies in routine practice. But only 23 % of respondents use Adaptive Support Ventilation (ASV) and analogues as primary mode in their routine practice, 9 % point to Intellivent-ASV®, less than 1 % point to PAV + TM (Proportional Assist Ventilation) and nobody point to NAVA (Neurally Adjusted Ventilatory Assist) and Smart Care®. Over half of respondents (62 %) from clinicians who have access to this technology pointed to the lack of knowledge about closed loop modes; 60 % pointed to insufficient education and 40 % pointed to the lack of equipment. These facts demonstrate the necessity of additional educational programs for implementation of modern technologies in practice, need for organization of post customer service for respirators and provision of consumables in some hospitals. CONCLUSIONS: this questionnaire showed that 85 % of practitioners have heard about closed-loop ventilation modes, and half of them had access to these technologies in routine practice, but just 30 % regularly use one of these technologies.

Supporting all breaths versus supporting some breaths during synchronised mechanical ventilation in neonates: a systematic review and meta-analysis

BackgroundNational Institute for Health and Clinical Effectiveness (NICE), UK, guideline published in 2019 recommends the use of volume-targeted ventilation (VTV). It recommends synchronised intermittent mandatory ventilation (SIMV) over the modes...

Model-based Estimation of Neonatal Pleural Pressure

Spontaneous breathing during mechanical ventilation is common in the neonatal intensive care unit. The breathing efforts in spontaneous breaths generate negative pressures in the pleural space, complicating model-based analysis due to unknown parameter tradeoff. This paper estimates the pleural pressure and elastance in a single compartment model applied to data from a neonate undergoing synchronous intermittent mandatory ventilation. Two sets of 60 breaths were analysed. Resistance is empirically modelled based on endotracheal tube dimensions. Breath-to-breath elastance is estimated from expiration data, assuming passive expiration, and inspiratory pleural pressure is modelled using B-spline functions. Typical breathing trends were observed, patient-triggered inspiration was apparent, and the work of breathing was significantly decreased in ventilator supported breaths compared to unsupported breaths. Additionally, examples of ventilator-patient asynchrony were observed when comparing pleural pressure to airway pressure. This study contributes to the development of computational models for respiration mechanics. The fundamental aim is to provide clinicians with more physiological insight and tools to improve neonatal ventilation support.

COVID-19 and pneumothorax, pneumomediastinum, subcutaneous emphysema: Analysis of risk factors.

In this study, we aimed to analyze the risk factors of barotrauma in patients who were followed in the intensive care unit due to novel coronavirus disease 2019 (COVID-19) pneumonia. Between March 2020 and January 2021, a total of 261 patients (155 males, 106 females; mean age: 63.3±15.3 years; range, 11 to 91 years) who were followed in the intensive care unit due to COVID-19 pneumonia and were diagnosed with pneumothorax, pneumomediastinum, and subcutaneous emphysema were retrospectively analyzed. Demographics data of the patients, past and current medical history, clinical management, patient progress, and survival data were obtained from medical records of our hospital. Twenty-seven of the patients were diagnosed with barotrauma. A total of 88.8% of the patients were followed with intubation. The development of pneumothorax, pneumomediastinum, and subcutaneous emphysema due to barotrauma was not dependent on sex, smoking/non-smoking status, using/not using corticosteroids, or comorbid diseases. There was a significant correlation between pneumothorax, pneumomediastinum, and subcutaneous emphysema development in intubated patients with different ventilator modes. Changing the ventilator mode from synchronized intermittent mandatory ventilation to airway pressure release ventilation increased the possibility of barotrauma by 15 times. Despite all lung-protective applications, barotrauma is a common complication, particularly in mechanically ventilated patients who have COVID-19 pneumonia with severe acute respiratory distress syndrome. Mechanical ventilator pressure modes should be patientspecific and followed carefully and frequently for the risk of barotrauma.

DYSPHAGIA FOLLOWING HOSPITALIZATION IN NURSING HOME RESIDENTS WITH ALZHEIMER’S DISEASE AND RELATED DEMENTIAS

Abstract Dysphagia frequently occurs in nursing home (NH) residents with Alzheimer’s Disease and Related Dementias (ADRD), often leading to serious health outcomes (e.g., pneumonia, malnutrition, reduced quality of life). While it is known that hospitalized NH residents with ADRD experience high rates of iatrogenic complications, dysphagia following discharge has not been examined. A retrospective cohort of all NH residents in the US (older adults aged ≥66) with advanced ADRD (Cognitive Function Scale ≥2), hospitalized between 2013-2017, and without a feeding tube or reported dysphagia on a Minimum Data Set (MDS) 3.0 assessment within 120 days prior to hospitalization was constructed. Treatment with intermittent mandatory ventilation (IMV) or non-invasive ventilation (NIV) during hospitalization and dysphagia status on the first post-hospitalization MDS was recorded. Data were analyzed using descriptive statistics and random effects multivariate logistic models that adjusted for age, gender, race/ethnicity, CFS score, ADL score, and comorbidities. Among the 805,199 residents with ADRD who survived the hospitalization and returned to the NH, new onset dysphagia occurred in 53,807 (6.7%; 95% CI 6.6-6.7) of residents. After adjustment, invasive mechanical ventilation (IMV) use was associated with increased risk of new onset of dysphagia (AOR 1.5; 95% CI 1.4-1.6) and non-invasive mechanical ventilation (NIMV) only slightly increased the risk (AOR 1.3; 95% 1.2-1.3). NH residents with ADRD are at risk for dysphagia following hospitalization. These findings emphasize the importance of swallowing evaluation and dysphagia treatment during hospitalization for ADRD patients, especially those treated with IMV or NIV, to prevent further negative health outcomes.

Comparison of pressure support ventilation and proportional assist ventilation plus for weaning from mechanical ventilation in critically ill patients

Background: Pressure support ventilation (PSV) is a widely used weaning mode that provides varying amount of support with changing lung characteristics. Proportional-assist ventilation plus (PAV+) is a new mode that automatically adjusts to changes in the respiratory system. Aim: This study compared PSV and PAV+ for weaning from mechanical ventilation. Methods: This was a prospective, randomised, control study enrolling 23 adult patients, mechanically ventilated for at least 48 h after passing SBT criteria and a PSV trial of 30 min. They were randomised to receive either PAV+ (Group 1) or PSV (Group 2). A washout time of 30 min was given for patients in either of the group in order to nullify the effect of the previous PSV mode. Two arterial blood gas samples were taken, during the assessment of SBT readiness, and after 60 min on the randomised weaning mode. Clinical signs of respiratory distress and objective weaning criteria were noted. Success and duration of weaning, rapid shallow breathing index (RSBI), rapid shallow breathing index rate (RSBI rate), haemodynamic and respiratory parameters were noted. Results: 13 patients were randomised to PAV+ group; 10 patients to PSV group. Demographic data were similar in both groups. RSBI, RSBI rate, arterial blood gas analysis, peak and mean inspiratory pressure were not different in either group. The average length of ICU stay, duration to wean and days to extubate were almost similar in both groups. Conclusion: Both PAV+ mode and PSV can be used with equal efficiency in patients ready for weaning.

Patient-Ventilator Asynchrony: The Power Struggle

Patient ventilator asynchrony (PVA) is a prevalent phenomenon seen in almost 25% of our intensive care unit patients. PVA can be trigger asynchrony, flow asynchrony, cycle asynchrony or mode asynchrony. Ineffective triggering is the most commonly occurring asynchrony. The best way to identify PVA is via the ventilator graphics. Corrective steps and manipulating the ventilator on the conventional mode to suit the patient's needs can help reduce the incidence of PVA. Recent advances have given rise to newer modes of ventilation such as Neurally Adjusted Ventilatory Assist and Proportional Assist Ventilation with the goal of reducing the frequency of PVA. Many new methods to reduce asynchronies are being studied; however additional large scale trials are needed to come to conclusive results. This article is an attempt to simplify the various asynchronies for better application to all healthcare professionals.

Comparison of Synchronised Intermittent Mandatory Ventilation with Pressure Support versus Assist Control mode of ventilation on time to extubation

Introduction: Increased work of breathing causing inspiratory muscle fatigue can delay extubation. Aim: This study compared the time taken for extubation in patients admitted with acute respiratory failure and ventilated with assist control mode (ACV) of ventilation or synchronised intermittent mandatory ventilation and Pressure Support (SIMV-PS). Patients and Methods: This was an observational study conducted in medical and surgical intensive care unit of a tertiary care hospital in South India. Patients receiving invasive mechanical ventilation for more than 24 hours were enrolled into the study. Demographic data, ventilator settings, ABG values after initiation of mechanical ventilation and before extubation, change of initial mode were recorded. The primary outcome was to determine the difference in the time taken for extubation (hours). Result: A total of 34 subjects were enrolled, twenty in SIMV-PS and fourteen subjects in ACV. The median age of the subjects was 53 years, 23 (68%) were males and 11 (32%) were females. The median (interquartile range) of Acute Physiology and Chronic Health Evaluation II (APACHE II) score was 18.5 (14, 29). Majority had a diagnosis of sepsis (23.5%) and pneumonia (17.6%). The median time on mechanical ventilation in SIMV-PS group was 90 h (57, 133) and in ACV group was 131 h (64, 258). There were also no statistical differences in the duration of weaning (p). Conclusion: Mechanical ventilation with assist control mode of ventilation or synchronised intermittent mandatory ventilation and pressure support are comparable in the time to weaning patients off ventilator.

An addition of tidal volume (volume guarantee) to synchronised intermittent mandatory ventilation in neonates with respiratory distress syndrome – A randomised controlled trial

An addition of tidal volume (volume guarantee) to synchronised intermittent mandatory ventilation in neonates with respiratory distress syndrome – A randomised controlled trial