This multi-panel figure illustrates a comparative analysis of two mechanical ventilation modes: Conventional Mechanical Ventilation (CMV) and Apneustic Anesthesia Ventilation (AAV). Section A provides idealized schematic waveforms for pressure, flow, and volume over time. CMV is characterized by intermittent pressure increases from baseline, while AAV (similar to Airway Pressure Release Ventilation or APRV) maintains an elevated baseline pressure (PHIGH) for a prolonged duration (THIGH) with brief, rapid releases to a lower pressure (PLOW) during a shorter interval (TLOW). Section B displays corresponding real-time example waveforms, highlighting that AAV maintains higher lung volumes throughout the respiratory cycle. Section C presents thoracic computed tomography (CT) scans in transverse, coronal, and sagittal planes, comparing lung recruitment and aeration between modes. The AAV images demonstrate improved lung inflation and more uniform density across the parenchyma compared to CMV, where areas of increased dependent opacification suggest potential atelectasis. This resource is designed for critical care and anesthesia education, focusing on respiratory physiology, ventilator waveform analysis, and the impact of ventilation strategies on pulmonary recruitment.

This diagnostic graphic displays three stacked ventilator waveforms (Volume, Pressure, and Flow Rate) over a 30-second interval, demonstrating mechanical ventilation in assisted mode. The top graph shows Tidal Volume (Vt) pulsing consistently to approximately 500 mL with a distinct plateau indicating an end-inspiratory hold. The middle Pressure-time waveform illustrates critical respiratory parameters: a negative deflection reaching the trigger pressure (Ptrig) of -2 cmH2O initiates each breath, followed by a rapid rise to a peak inspiratory pressure (Ppeak) of ~25 cmH2O. An inspiratory hold reveals a plateau pressure (Pplateau) of ~22 cmH2O, with the cycle concluding at a positive end-expiratory pressure (PEEP) of ~5 cmH2O. The bottom Flow Rate graph displays corresponding inspiratory and expiratory flow pulses. Annotations mark key temporal points: initial inspiration (Ii), inspiratory hold (Ih), end-inspiration (Ei), and end-expiration (Ef). This visualization is essential for understanding ventilator-patient synchrony, mechanical lung properties (compliance and resistance), and the functioning of pressure-triggered assisted ventilation modes.

A series of six line graphs (labeled a–f) comparing two mechanical ventilation modes, Low Tidal Volume (LTV, blue) and Airway Pressure Release Ventilation (APRV, red), over a 24-hour timeline in a simulation of pulmonary blast lung injury. The graphs track key respiratory parameters: (a) PaO2, showing an initial decline before stabilizing around hour 9; (b) PaCO2, demonstrating higher levels in the APRV group; (c) End-Expiratory Lung Volume (EELV), which shows APRV maintains significantly higher functional residual capacity; (d) Fraction of inspired oxygen (FiO2), illustrating relatively high oxygen requirements for both modes; (e) P/F ratio, indicating stabilization of gas exchange; and (f) Peak Ventilatory Pressures (Ppeak), showing LTV requires higher pressures to maintain target volumes. Each data point includes error bars representing variance. The figure serves to compare the physiological impacts of different ventilatory strategies on oxygenation, ventilation efficiency, and lung recruitment in acute respiratory distress scenarios.

This physiological monitoring graphic displays mechanical ventilation waveforms across three distinct modes: Pressure Support Ventilation (PSV) in panel A, Biphasic Positive Airway Pressure (BIPAP) in panel B, and Airway Pressure Release Ventilation (APRV) in panel C. Each panel illustrates time-synced tracings of airway pressure (Paw), muscle pressure (Pmus), distending pressure (PDist_EM), flow (L/s), and tidal volume (L). In PSV (A), the waveforms show regular, patient-triggered breaths with stable tidal volumes and consistent Pmus deflections. BIPAP (B) reveals two levels of baseline pressure with significant spontaneous effort (negative Pmus) during the lower pressure phase, resulting in more variable flow and volume patterns. APRV (C) demonstrates prolonged high-pressure phases with brief releases, characterized by high respiratory drive and frequent, irregular spontaneous breathing efforts superimposed on the ventilator cycle. Key metrics provided below the graphs include respiratory system elastance (Ers), airway occlusion pressure (P0.1), and patient work of breathing (WOBp), used to analyze patient-ventilator synchrony and inspiratory effort in critically ill patients, such as those with COVID-19 ARDS.

A comparison chart consisting of two sets of mechanical ventilation waveforms (pressure-time and flow-time curves) demonstrating different control variables. The upper panel (Ventilator 1) shows characteristics of volume-controlled ventilation, where the pressure curve (red) reaches a peak and then maintains a plateau, while the flow curve (purple) rises instantaneously and remains constant before falling, indicating a square flow waveform. The lower panel (Ventilator 2) illustrates pressure-controlled ventilation. In this mode, the pressure curve (red) rapidly rises to a set level (approximately 15 mbar) and maintains a plateau, while the flow curve (purple) shows a peak followed by a decelerating ramp pattern. Both panels show three respiratory cycles over an approximately 8-second window, with vertical dashed lines marking the start of inspiration. These waveforms are critical for respiratory therapy education to distinguish between volume-preset and pressure-preset mechanical ventilation strategies.

This Comparison Chart displays synchronized respiratory waveforms over 40 seconds during volume-controlled mechanical ventilation. From top to bottom, the four graphs include: 1) Flow [l/min], showing inspiratory and expiratory phases with zero-flow plateaus during maneuvers. 2) Airway pressure (Paw [cmH2O]), highlighting 'Set PEEP', 'PEEPtot' during an expiratory pause, and 'Airway plateau pressure' and 'Airway driving pressure' during an inspiratory hold. 3) Esophageal pressure (Pes [cmH2O]), used as a surrogate for pleural pressure, showing end-expiratory/end-inspiratory values and minor cardiac artifacts. 4) Transpulmonary pressure (Plung [cmH2O]), calculated as Paw minus Pes, illustrating 'Transpulmonary driving pressure' and 'End-inspiratory transpulmonary pressure'. The visual illustrates critical bedside monitoring for Acute Respiratory Distress Syndrome (ARDS), focusing on lung mechanics, intrinsic PEEP, and the prevention of ventilator-induced lung injury (VILI) by quantifying driving pressures and plateau pressures through hold maneuvers.