Mandatory Minute Ventilation (MMV) as a rescue mode of ventilation in late preterm and term infants

Mandatory Minute Ventilation (MMV) as a rescue mode of ventilation in late preterm and term infants | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Short Report Mandatory Minute Ventilation (MMV) as a rescue mode of ventilation in late preterm and term infants Adrita Bose, Md Habibullah Sk, Bijan Saha This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-3964770/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Mandatory Minute Ventilation (MMV) is a valuable rescue mode for late preterm and term infants experiencing challenges with hyperventilation. In this prospective study, seven infants were ventilated using MMV as a rescue mode. Infants initially under Pressure Control-Assist/Control with Volume Guarantee (PC-AC + VG) mode were transitioned to Pressure Control-MMV (PC-MMV) using Drager Babylog VN 600. All infants were late preterm or term, without major congenital malformations. Our findings suggest that transitioning to PC-MMV resulted in improved gas exchange stability, reduced respiratory rate, and facilitated early weaning. The study's strengths include prospective data collection and a uniform cohort. However, limitations include the exclusive focus on late preterm and term infants and the lack of exploration of clinical or long-term outcomes. The use of MMV as a rescue mode in these infants warrants further investigation in future clinical studies. Conclusion : MMV offers a promising approach for managing hyperventilation with increase work of breathing as a rescue mode in late preterm and term infants. Further research is needed to establish the efficacy and long-term outcomes of MMV in neonatal care. Mandatory Minute Ventilation Late preterm and term infants Hyperventilation Respiratory distress Volume Guarantee What is known Volume Guarantee (VG) is a commonly used ventilation strategy in neonatal care. What is new The study underscores the effectiveness of transitioning from PC-AC+VG to PC-MMV in enhancing gas exchange stability, lowering respiratory rate, and promoting early weaning in late preterm and term infants facing hyperventilation challenges resulting increase work of breathing. Introduction Mandatory Minute Ventilation (MMV) promotes development of patient initiated breathing patterns, while guaranteeing a minimum level of minute ventilation. Spontaneously initiated pressure-supported synchronized breaths by the infant are augmented by mandatory breaths featuring pressure limitation and volume guarantee. These mandatory breaths come into play when the minute volume produced by pressure-supported breaths falls below the user-set mandatory minute volume( 1 ). Volume Targeted Ventilation (VTV)/ Volume Guarantee (VG) is on the rise in neonatal intensive care units. Systematic reviews indicate that VTV offers more precise control over tidal volume(VT) and carbon dioxide (CO 2 ) levels, leading to reduced mortality and bronchopulmonary dysplasia rates, fewer occurrences of pneumothoraxes and serious intraventricular hemorrhages, as well as a decreased duration of ventilation( 2 ). However, maintaining the targeted VT in hyperventilating infants with increase work of breathing during VG poses a challenge. If the infant exhibits vigorous respiratory efforts, leading to a substantial increase in inspiratory VT beyond the target, several VG ventilators may not generate inflation pressure beyond positive end-expiratory pressure(PEEP). This could result in an elevated level of minute ventilation, which is crucial for removing CO 2 from the lungs. This may lead to fatigue, acidosis, and increased fluctuations in pCO 2 . In this context, we share a case series detailing our experience with MMV as a rescue mode for infants facing these complex challenges. Methodology We conducted a prospective evaluation involving 15 infants who underwent ventilation using MMV as a rescue ventilation strategy. Initially, these infants were under Assist/Control ventilation with volume guarantee (PC/AC + VG) using either Drager Babylog VN 600 (PC-AC + VG) or Drager Babylog 8000+ (SIPPV + VG). Subsequently, the ventilation mode was transitioned to PC-MMV(Pressure Control-Mandatory Minute Ventilation) using Drager Babylog VN 600. All infants in the study were late preterm or term, and none had any documented major congenital malformations. The institutional ethics committee of the Institute of Post Graduate Medical Education and Research, Kolkata, India had approved this study (IPGME&R/IEC/2023/1074). Written informed consent was obtained from all legal guardians prior to their participation. Case series Ventilator parameters are summarized in Table 1 . Case 1 A female infant born at 39 week with severe perinatal asphyxia (cord blood pH 7.0, base deficit − 19) was initially placed on mechanical ventilation using PC-AC + VG. However, due to hyperventilation in response to acidosis and excessive inspiratory VT, the ventilator promptly reduced pressure to PEEP levels. The infant also developed persistent pulmonary hypertension of the newborn (PPHN) and was subsequently transitioned to PC-MMV. After 2 hours of PC-MMV, her respiratory rate and pCO2 stabilized. She continued on PC-MMV for 110 hours before successful extubation. Case 2 A 37-week male infant, delivered by emergency caesarean section due to fetal distress with thick meconium-stained liquor, initially presented with severe respiratory distress consistent with meconium aspiration syndrome (MAS). Despite initiating PC-AC + VG with a 6ml/kg target volume, the infant continued to hyperventilate. Attempted interventions, including increasing the target VT to 8ml/kg and administering fentanyl for sedation, were ineffective. Due to persistently increased work of breathing and ventilator dyssynchrony, the mode was switched to PC-MMV. The infant tolerated PC-MMV well without the need for increased sedation and was successfully extubated after 90 hours of mechanical ventilation. Case 3 A 40-week male infant presented on day 28 of life with acute respiratory distress, and a chest x-ray indicated viral pneumonia, with a positive respiratory viral panel for adenovirus. Initial attempts at stabilization with nasal intermittent positive pressure ventilation for 2 hours were unsuccessful, leading to intubation with PC-AC + VG. Due to persistent tachypnea and increased work of breathing, the mode was changed to PC-MMV. After 2 hours of PC-MMV, the infant's work of breathing decreased, and successful extubation was achieved after 124 hours of ventilation. Case 4 A 35-week male infant born to a diabetic mother with X-ray findings indicative of respiratory distress syndrome. Despite surfactant administration, the baby did not improve, displaying severe tachypnea and increased work of breathing, leading to intubation. Antibiotics were initiated due to suspected congenital pneumonia. Persistent rapid breathing on PC-AC + VG necessitated a shift to PC-MMV. Gradually, respiratory stability was achieved. Subsequent blood culture revealed a positive result for Klebsiella pneumoniae. Case 5 A 38-week male infant presented with severe watery diarrhoea, exhibiting severe metabolic acidosis (pH 6.9, base deficit − 23). The infant exhibited extreme tachypnea in response to severe acidosis. The pressure curve in PC-AC + VG flattened because of the spontaneous high VT generated by the infant. He was subsequently transitioned to MMV + PS, along with aggressive fluid management, leading to respiratory stabilization within a few hours. Case 6 A 36-week male infant, intubated in the delivery room for severe perinatal asphyxia, exhibited hyperventilation due to acidosis. Initially placed on PC-AC + VG, the mode was later shifted to PC-MMV due to the flattening of the pressure curve. The infant later developed PPHN. Tachypnea subsided after a few hours of PC-MMV, and his FiO 2 requirements gradually improved. Case 7 A 36-week outborn female infant of a diabetic mother was transferred in an intubated condition, diagnosed with malignant transient tachypnea of the newborn. However, the infant exhibited tachypnea and increased work of breathing on PC-AC + VG. Subsequently, the mode was shifted to PC-MMV, resulting in a reduction in respiratory rate, and the baby could be extubated after 40 hours. These infants often exceeded the target VT levels due to hyperventilation, and five infants experienced hypocapnia before the initiation of PC-MMV. However, it's important to note that based on these data, we cannot definitively exclude the occurrence of these adverse events during prolonged periods of ventilation. No instances of hemodynamic instability, air leaks, or adverse events related to PC-MMV use were documented in all seven cases. Discussion In this prospective study, we examined ventilator parameters and blood gases in hyperventilating infants during MMV ventilation. Within the same group of infants, we compared those initially on PC-AC + VG mode and subsequently shifted to PC-MMV. Our findings demonstrated that PC-MMV provides the advantage of achieving even more stable gas exchange, lowering the respiratory rate, decreasing work of breathing and facilitating early weaning. Infants with conditions like MAS, PPHN, and severe metabolic acidosis may display unmanageable tachypnea even on with VG ventilation. In these infants with strong breathing effort during ventilator inflation, if the inspiratory VT exceeds the target VT, the ventilator VG algorithm adjusts by reducing inflation pressure, occasionally reaching the PEEP level. This scenario leads to an increased respiratory workload, reducing the MAP, and delivering lower VT and minute ventilation. This could potentially lead to a decrease in lung volume and contribute to fluctuations in PaCO 2 ( 3 ). In many neonatal centres, this issue is commonly addressed by raising the set volume target. However, this approach puts the infant at risk of hyperventilation and a significant drop in pCO 2 . Simultaneously, increasing VT beyond physiological limits is not a viable option. Alternative choices include adopting advanced rescue modes such as high frequency oscillatory ventilation (HFOV)as a lung-protective strategy, or administering sedation to reduce the respiratory drive itself. In the past, our approach involved transitioning infants to HFOV for such cases, requiring a more extended duration of ventilation compared to the use of PC-MMV. In the given situations, we observed that transitioning from PC-AC + VG to PC-MMV mode resulted in decreased work of breathing, a lower respiratory rate, and facilitated early weaning in infants. In all infants, we observed that spontaneous breaths (enhanced with pressure support) accounted for nearly 100% of the total minute ventilation in PC-MMV mode. Pressure support (PS) overcome the resistance of the tracheal tube and the lower respiratory system resistance, thereby reducing the work of breathing. The adaptive function controlling MMV ventilation mode can be summarized by the equation: MV total = MV mand + MV spon (MV total the total minute volume, MV mand minute volume from triggered or untriggered mandatory breaths, and MV spon minute volume from pressure-supported spontaneous breaths) The spontaneous minute volume varies based on respiratory drive and the tidal volume of each spontaneous breath. The ventilator software continuously compares the measured MV total with the set minute volume to determine when and how many mandatory breaths should be delivered. If the infant is breathing vigorously, generating an MV spon that exceeds the set minute volume, MV mand is reduced to zero. Throughout this process, the baby is safeguarded from hypoventilation by the assurance of a minimum minute volume( 1 ). However, utilizing the PC-AC + VG ventilation mode would likely lead to a temporary increase in minute ventilation and a decrease in pCO2. In infants exerting strong respiratory efforts, the VG algorithm lowers PIP to maintain VTe mand close to the set level. Consequently, the ventilator's driving pressure (PIP–PEEP) and its contribution to the work of breathing in these infants are often minimal. This can ultimately result in exhaustion and hypercapnia. To date, only two observational studies have evaluated MMV in newborns, showing that MMV sustains sufficient gas exchange with reduced mechanical support compared to SIMV ( 4 , 5 ). A small crossover study (n = 20) on MMV in moderately mature preterm neonates (> 33 weeks gestation) by Guthrie et al. revealed that, despite producing similar PIP and PEEP, MMV's reduction in mechanical breaths and mean airway pressure could potentially lower the risk of certain long-term complications linked to mechanical ventilation( 5 ). Our study's primary strength lies in the prospective data collection and the uniformity of the cohort. However, it is constrained by being limited to a rescue mode and exclusively including late preterm and term infants. Additionally, no exploration of clinical or long-term outcomes has been undertaken. The application of PC-MMV ventilation in these infants requires further establishment through future clinical studies. Conclusion Mandatory Minute Ventilation (MMV) is explored as a rescue mode in late preterm and term infants experiencing challenging with hyperventilation resulting in increased work of breathing. The transition from PC-AC + VG to PC-MMV demonstrated improved stability in gas exchange, reduced respiratory rate, and facilitated early weaning in seven cases. While acknowledging limitations, such as the absence of long-term outcomes exploration, the study advocates further research to establish the efficacy of PC-MMV in neonatal care. Abbreviations VG: Volume Guarantee VTV: Volume Targeted Ventilation PC-MMV: Pressure Control-Mandatory Minute Ventilation MAS: Meconium Aspiration Syndrome PPHN: Persistent Pulmonary Hypertension of the Newborn SIPPV: Synchronized Intermittent Positive Pressure Ventilation. VT: Tidal Volume CO2: Carbon Dioxide PIP: Peak Inspiratory Pressure PEEP: Positive End-Expiratory Pressure MV: Minute Ventilation PC-AC: Pressure Control-Assist/Control FiO2: Fraction of Inspired Oxygen MAP: Mean Airway Pressure HFOV: High Frequency Oscillatory Ventilation PaCO2: Partial Pressure of Carbon Dioxide in Arterial Blood Declarations Funding sources None Conflict of interests The authors declare no conflict of interest Funding none Conflicts of interest/Competing interests The authors declare no competing interests. Authors' contributions Adrita Bose : Case management and manuscript preparation Md Habibullah Sk : Case management , manuscript preparation and review Bijan Saha : Literature search , manuscript review and critical analysis All the authors approved the final manuscript as submitted and agree to be accountable for all aspect of the work. Ethics approval & Consent to participate Informed consent was obtained from the legal guardian of all included participants. Consent for publication Informed consent was obtained from the legal guardian of all included participants. References Pillow J. Mandatory Minute Ventilation: Background and Clinical Applications. Drägerwerk AG & Co. KGaA. 2019: 9106653. Klingenberg C, Wheeler KI, McCallion N, Morley CJ, Davis PG. Volume-targeted versus pressure-limited ventilation in neonates. Cochrane Database Syst Rev. 2017;10:CD003666. Keszler M. Volume-targeted ventilation: one size does not fit all. Evidence-based recommendations for successful use. Arch Dis Child Fetal Neonatal Ed. 2019;104:F108–12. Claure N, Gerhardt T, Hummler H, Everett R, Bancalari E. Computer-controlled minute ventilation in preterm infants undergoing mechanical ventilation. J Pediatr. 1997 Dec;131(6):910-3. doi: 10.1016/s0022-3476(97)70042-8. PMID: 9427899. Guthrie SO, Lynn C, Lafleur BJ, Donn SM, Walsh WF. A crossover analysis of mandatory minute ventilation compared to synchronized intermittent mandatory ventilation in neonates. J Perinatol. 2005 Oct;25(10):643-6. doi: 10.1038/sj.jp.7211371. PMID: 16079905. Table Table 1 is available in the Supplementary Files section. Additional Declarations No competing interests reported. Supplementary Files Table1.docx Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Spontaneously initiated pressure-supported synchronized breaths by the infant are augmented by mandatory breaths featuring pressure limitation and volume guarantee. These mandatory breaths come into play when the minute volume produced by pressure-supported breaths falls below the user-set mandatory minute volume(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eVolume Targeted Ventilation (VTV)/ Volume Guarantee (VG) is on the rise in neonatal intensive care units. Systematic reviews indicate that VTV offers more precise control over tidal volume(VT) and carbon dioxide (CO\u003csub\u003e2\u003c/sub\u003e) levels, leading to reduced mortality and bronchopulmonary dysplasia rates, fewer occurrences of pneumothoraxes and serious intraventricular hemorrhages, as well as a decreased duration of ventilation(\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eHowever, maintaining the targeted VT in hyperventilating infants with increase work of breathing during VG poses a challenge. If the infant exhibits vigorous respiratory efforts, leading to a substantial increase in inspiratory VT beyond the target, several VG ventilators may not generate inflation pressure beyond positive end-expiratory pressure(PEEP). This could result in an elevated level of minute ventilation, which is crucial for removing CO\u003csub\u003e2\u003c/sub\u003efrom the lungs. This may lead to fatigue, acidosis, and increased fluctuations in pCO\u003csub\u003e2\u003c/sub\u003e.\u003c/p\u003e \u003cp\u003eIn this context, we share a case series detailing our experience with MMV as a rescue mode for infants facing these complex challenges.\u003c/p\u003e"},{"header":"Methodology","content":"\u003cp\u003eWe conducted a prospective evaluation involving 15 infants who underwent ventilation using MMV as a rescue ventilation strategy. Initially, these infants were under Assist/Control ventilation with volume guarantee (PC/AC\u0026thinsp;+\u0026thinsp;VG) using either Drager Babylog VN 600 (PC-AC\u0026thinsp;+\u0026thinsp;VG) or Drager Babylog 8000+ (SIPPV\u0026thinsp;+\u0026thinsp;VG). Subsequently, the ventilation mode was transitioned to PC-MMV(Pressure Control-Mandatory Minute Ventilation) using Drager Babylog VN 600. All infants in the study were late preterm or term, and none had any documented major congenital malformations. The institutional ethics committee of the Institute of Post Graduate Medical Education and Research, Kolkata, India had approved this study (IPGME\u0026amp;R/IEC/2023/1074). Written informed consent was obtained from all legal guardians prior to their participation.\u003c/p\u003e\n\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\n\u003ch2\u003eCase series\u003c/h2\u003e\n\u003cp\u003eVentilator parameters are summarized in \u003cem\u003eTable\u0026nbsp;1\u003c/em\u003e.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\n\u003ch2\u003eCase 1\u003c/h2\u003e\n\u003cp\u003eA female infant born at 39 week with severe perinatal asphyxia (cord blood pH 7.0, base deficit \u0026minus;\u0026thinsp;19) was initially placed on mechanical ventilation using PC-AC\u0026thinsp;+\u0026thinsp;VG. However, due to hyperventilation in response to acidosis and excessive inspiratory VT, the ventilator promptly reduced pressure to PEEP levels. The infant also developed persistent pulmonary hypertension of the newborn (PPHN) and was subsequently transitioned to PC-MMV. After 2 hours of PC-MMV, her respiratory rate and pCO2 stabilized. She continued on PC-MMV for 110 hours before successful extubation.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e\n\u003ch2\u003eCase 2\u003c/h2\u003e\n\u003cp\u003eA 37-week male infant, delivered by emergency caesarean section due to fetal distress with thick meconium-stained liquor, initially presented with severe respiratory distress consistent with meconium aspiration syndrome (MAS). Despite initiating PC-AC\u0026thinsp;+\u0026thinsp;VG with a 6ml/kg target volume, the infant continued to hyperventilate. Attempted interventions, including increasing the target VT to 8ml/kg and administering fentanyl for sedation, were ineffective. Due to persistently increased work of breathing and ventilator dyssynchrony, the mode was switched to PC-MMV. The infant tolerated PC-MMV well without the need for increased sedation and was successfully extubated after 90 hours of mechanical ventilation.\u003c/p\u003e\n\u003cdiv id=\"Sec6\" class=\"Section3\"\u003e\n\u003ch2\u003eCase 3\u003c/h2\u003e\n\u003cp\u003eA 40-week male infant presented on day 28 of life with acute respiratory distress, and a chest x-ray indicated viral pneumonia, with a positive respiratory viral panel for adenovirus. Initial attempts at stabilization with nasal intermittent positive pressure ventilation for 2 hours were unsuccessful, leading to intubation with PC-AC\u0026thinsp;+\u0026thinsp;VG. Due to persistent tachypnea and increased work of breathing, the mode was changed to PC-MMV. After 2 hours of PC-MMV, the infant's work of breathing decreased, and successful extubation was achieved after 124 hours of ventilation.\u003c/p\u003e\n\u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\n\u003ch2\u003eCase 4\u003c/h2\u003e\n\u003cp\u003eA 35-week male infant born to a diabetic mother with X-ray findings indicative of respiratory distress syndrome. Despite surfactant administration, the baby did not improve, displaying severe tachypnea and increased work of breathing, leading to intubation. Antibiotics were initiated due to suspected congenital pneumonia. Persistent rapid breathing on PC-AC\u0026thinsp;+\u0026thinsp;VG necessitated a shift to PC-MMV. Gradually, respiratory stability was achieved. Subsequent blood culture revealed a positive result for Klebsiella pneumoniae.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\n\u003ch2\u003eCase 5\u003c/h2\u003e\n\u003cp\u003eA 38-week male infant presented with severe watery diarrhoea, exhibiting severe metabolic acidosis (pH 6.9, base deficit \u0026minus;\u0026thinsp;23). The infant exhibited extreme tachypnea in response to severe acidosis. The pressure curve in PC-AC\u0026thinsp;+\u0026thinsp;VG flattened because of the spontaneous high VT generated by the infant. He was subsequently transitioned to MMV\u0026thinsp;+\u0026thinsp;PS, along with aggressive fluid management, leading to respiratory stabilization within a few hours.\u003c/p\u003e\n\u003c/div\u003e\n\u003ch2\u003eCase 6\u003c/h2\u003e\n\u003cp\u003eA 36-week male infant, intubated in the delivery room for severe perinatal asphyxia, exhibited hyperventilation due to acidosis. Initially placed on PC-AC\u0026thinsp;+\u0026thinsp;VG, the mode was later shifted to PC-MMV due to the flattening of the pressure curve. The infant later developed PPHN. Tachypnea subsided after a few hours of PC-MMV, and his FiO\u003csub\u003e2\u003c/sub\u003e requirements gradually improved.\u003c/p\u003e\n\u003ch2\u003eCase 7\u003c/h2\u003e\n\u003cp\u003eA 36-week outborn female infant of a diabetic mother was transferred in an intubated condition, diagnosed with malignant transient tachypnea of the newborn. However, the infant exhibited tachypnea and increased work of breathing on PC-AC\u0026thinsp;+\u0026thinsp;VG. Subsequently, the mode was shifted to PC-MMV, resulting in a reduction in respiratory rate, and the baby could be extubated after 40 hours.\u003c/p\u003e\n\u003cp\u003eThese infants often exceeded the target VT levels due to hyperventilation, and five infants experienced hypocapnia before the initiation of PC-MMV. However, it's important to note that based on these data, we cannot definitively exclude the occurrence of these adverse events during prolonged periods of ventilation. No instances of hemodynamic instability, air leaks, or adverse events related to PC-MMV use were documented in all seven cases.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn this prospective study, we examined ventilator parameters and blood gases in hyperventilating infants during MMV ventilation. Within the same group of infants, we compared those initially on PC-AC\u0026thinsp;+\u0026thinsp;VG mode and subsequently shifted to PC-MMV. Our findings demonstrated that PC-MMV provides the advantage of achieving even more stable gas exchange, lowering the respiratory rate, decreasing work of breathing and facilitating early weaning.\u003c/p\u003e \u003cp\u003eInfants with conditions like MAS, PPHN, and severe metabolic acidosis may display unmanageable tachypnea even on with VG ventilation. In these infants with strong breathing effort during ventilator inflation, if the inspiratory VT exceeds the target VT, the ventilator VG algorithm adjusts by reducing inflation pressure, occasionally reaching the PEEP level. This scenario leads to an increased respiratory workload, reducing the MAP, and delivering lower VT and minute ventilation. This could potentially lead to a decrease in lung volume and contribute to fluctuations in PaCO\u003csub\u003e2\u003c/sub\u003e(\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e). In many neonatal centres, this issue is commonly addressed by raising the set volume target. However, this approach puts the infant at risk of hyperventilation and a significant drop in pCO\u003csub\u003e2\u003c/sub\u003e. Simultaneously, increasing VT beyond physiological limits is not a viable option. Alternative choices include adopting advanced rescue modes such as high frequency oscillatory ventilation (HFOV)as a lung-protective strategy, or administering sedation to reduce the respiratory drive itself. In the past, our approach involved transitioning infants to HFOV for such cases, requiring a more extended duration of ventilation compared to the use of PC-MMV.\u003c/p\u003e \u003cp\u003eIn the given situations, we observed that transitioning from PC-AC\u0026thinsp;+\u0026thinsp;VG to PC-MMV mode resulted in decreased work of breathing, a lower respiratory rate, and facilitated early weaning in infants. In all infants, we observed that spontaneous breaths (enhanced with pressure support) accounted for nearly 100% of the total minute ventilation in PC-MMV mode. Pressure support (PS) overcome the resistance of the tracheal tube and the lower respiratory system resistance, thereby reducing the work of breathing. The adaptive function controlling MMV ventilation mode can be summarized by the equation:\u003c/p\u003e \u003cp\u003eMV\u003csub\u003etotal\u003c/sub\u003e = MV\u003csub\u003emand\u003c/sub\u003e + MV\u003csub\u003espon\u003c/sub\u003e\u003c/p\u003e \u003cp\u003e(MV\u003csub\u003etotal\u003c/sub\u003e the total minute volume, MV\u003csub\u003emand\u003c/sub\u003e minute volume from triggered or untriggered mandatory breaths, and MV\u003csub\u003espon\u003c/sub\u003e minute volume from pressure-supported spontaneous breaths)\u003c/p\u003e \u003cp\u003eThe spontaneous minute volume varies based on respiratory drive and the tidal volume of each spontaneous breath. The ventilator software continuously compares the measured MV\u003csub\u003etotal\u003c/sub\u003e with the set minute volume to determine when and how many mandatory breaths should be delivered. If the infant is breathing vigorously, generating an MV\u003csub\u003espon\u003c/sub\u003e that exceeds the set minute volume, MV\u003csub\u003emand\u003c/sub\u003e is reduced to zero. Throughout this process, the baby is safeguarded from hypoventilation by the assurance of a minimum minute volume(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eHowever, utilizing the PC-AC\u0026thinsp;+\u0026thinsp;VG ventilation mode would likely lead to a temporary increase in minute ventilation and a decrease in pCO2. In infants exerting strong respiratory efforts, the VG algorithm lowers PIP to maintain VTe\u003csub\u003emand\u003c/sub\u003e close to the set level. Consequently, the ventilator's driving pressure (PIP\u0026ndash;PEEP) and its contribution to the work of breathing in these infants are often minimal. This can ultimately result in exhaustion and hypercapnia.\u003c/p\u003e \u003cp\u003eTo date, only two observational studies have evaluated MMV in newborns, showing that MMV sustains sufficient gas exchange with reduced mechanical support compared to SIMV (\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e). A small crossover study (n\u0026thinsp;=\u0026thinsp;20) on MMV in moderately mature preterm neonates (\u0026gt;\u0026thinsp;33 weeks gestation) by Guthrie et al. revealed that, despite producing similar PIP and PEEP, MMV's reduction in mechanical breaths and mean airway pressure could potentially lower the risk of certain long-term complications linked to mechanical ventilation(\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e \u003cp\u003eOur study's primary strength lies in the prospective data collection and the uniformity of the cohort. However, it is constrained by being limited to a rescue mode and exclusively including late preterm and term infants. Additionally, no exploration of clinical or long-term outcomes has been undertaken. The application of PC-MMV ventilation in these infants requires further establishment through future clinical studies.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eMandatory Minute Ventilation (MMV) is explored as a rescue mode in late preterm and term infants experiencing challenging with hyperventilation resulting in increased work of breathing. The transition from PC-AC\u0026thinsp;+\u0026thinsp;VG to PC-MMV demonstrated improved stability in gas exchange, reduced respiratory rate, and facilitated early weaning in seven cases. While acknowledging limitations, such as the absence of long-term outcomes exploration, the study advocates further research to establish the efficacy of PC-MMV in neonatal care.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eVG: Volume Guarantee\u003c/p\u003e\n\u003cp\u003eVTV: Volume Targeted Ventilation\u003c/p\u003e\n\u003cp\u003ePC-MMV: Pressure Control-Mandatory Minute Ventilation\u003c/p\u003e\n\u003cp\u003eMAS: Meconium Aspiration Syndrome\u003c/p\u003e\n\u003cp\u003ePPHN: Persistent Pulmonary Hypertension of the Newborn\u003c/p\u003e\n\u003cp\u003eSIPPV: Synchronized Intermittent Positive Pressure Ventilation.\u003c/p\u003e\n\u003cp\u003eVT: Tidal Volume\u003c/p\u003e\n\u003cp\u003eCO2: Carbon Dioxide\u003c/p\u003e\n\u003cp\u003ePIP: Peak Inspiratory Pressure\u003c/p\u003e\n\u003cp\u003ePEEP: Positive End-Expiratory Pressure\u003c/p\u003e\n\u003cp\u003eMV: Minute Ventilation\u003c/p\u003e\n\u003cp\u003ePC-AC: Pressure Control-Assist/Control\u003c/p\u003e\n\u003cp\u003eFiO2: Fraction of Inspired Oxygen\u003c/p\u003e\n\u003cp\u003eMAP: Mean Airway Pressure\u003c/p\u003e\n\u003cp\u003eHFOV: High Frequency Oscillatory Ventilation\u003c/p\u003e\n\u003cp\u003ePaCO2: Partial Pressure of Carbon Dioxide in Arterial Blood\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eFunding sources\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNone\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no conflict of interest\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003enone\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflicts of interest/Competing interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026apos; contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAdrita Bose : Case management and manuscript preparation\u003c/p\u003e\n\u003cp\u003eMd Habibullah Sk : Case management , manuscript preparation and review\u003c/p\u003e\n\u003cp\u003eBijan Saha : Literature search , manuscript review and critical analysis\u003c/p\u003e\n\u003cp\u003eAll the authors approved the final manuscript as submitted and agree to be accountable for all aspect of the work.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval \u0026amp; Consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eInformed consent was obtained from the legal guardian of all included participants.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eInformed consent was obtained from the legal guardian of all included participants.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003ePillow J. Mandatory Minute Ventilation: Background and Clinical Applications. Dr\u0026auml;gerwerk AG \u0026amp; Co. KGaA. 2019: 9106653. \u003c/li\u003e\n\u003cli\u003eKlingenberg C, Wheeler KI, McCallion N, Morley CJ, Davis PG. Volume-targeted versus pressure-limited ventilation in neonates. Cochrane Database Syst Rev. 2017;10:CD003666. \u003c/li\u003e\n\u003cli\u003eKeszler M. Volume-targeted ventilation: one size does not fit all. Evidence-based recommendations for successful use. Arch Dis Child Fetal Neonatal Ed. 2019;104:F108\u0026ndash;12. \u003c/li\u003e\n\u003cli\u003eClaure N, Gerhardt T, Hummler H, Everett R, Bancalari E. Computer-controlled minute ventilation in preterm infants undergoing mechanical ventilation. J Pediatr. 1997 Dec;131(6):910-3. doi: 10.1016/s0022-3476(97)70042-8. PMID: 9427899. \u003c/li\u003e\n\u003cli\u003eGuthrie SO, Lynn C, Lafleur BJ, Donn SM, Walsh WF. A crossover analysis of mandatory minute ventilation compared to synchronized intermittent mandatory ventilation in neonates. J Perinatol. 2005 Oct;25(10):643-6. doi: 10.1038/sj.jp.7211371. PMID: 16079905. \u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Table","content":"\u003cp\u003eTable 1 is available in the Supplementary Files section.\u003c/p\u003e "}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Mandatory Minute Ventilation, Late preterm and term infants, Hyperventilation, Respiratory distress, Volume Guarantee","lastPublishedDoi":"10.21203/rs.3.rs-3964770/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-3964770/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eMandatory Minute Ventilation (MMV) is a valuable rescue mode for late preterm and term infants experiencing challenges with hyperventilation. In this prospective study, seven infants were ventilated using MMV as a rescue mode. Infants initially under Pressure Control-Assist/Control with Volume Guarantee (PC-AC + VG) mode were transitioned to Pressure Control-MMV (PC-MMV) using Drager Babylog VN 600. All infants were late preterm or term, without major congenital malformations. Our findings suggest that transitioning to PC-MMV resulted in improved gas exchange stability, reduced respiratory rate, and facilitated early weaning. The study's strengths include prospective data collection and a uniform cohort. However, limitations include the exclusive focus on late preterm and term infants and the lack of exploration of clinical or long-term outcomes. The use of MMV as a rescue mode in these infants warrants further investigation in future clinical studies.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConclusion\u003c/strong\u003e: MMV offers a promising approach for managing hyperventilation with increase work of breathing as a rescue mode in late preterm and term infants. Further research is needed to establish the efficacy and long-term outcomes of MMV in neonatal care.\u003c/p\u003e","manuscriptTitle":"Mandatory Minute Ventilation (MMV) as a rescue mode of ventilation in late preterm and term infants","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-02-21 06:16:32","doi":"10.21203/rs.3.rs-3964770/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"0e012752-f401-4841-9807-97e9ab4c535c","owner":[],"postedDate":"February 21st, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2024-02-21T06:16:32+00:00","versionOfRecord":[],"versionCreatedAt":"2024-02-21 06:16:32","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-3964770","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-3964770","identity":"rs-3964770","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}