Pressure Regulated Volume Control (PRVC): Set it and forget it?
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ABSTRACT:
SUBMITTER: Singh G
PROVIDER: S-EPMC7118406 | biostudies-literature | 2020
REPOSITORIES: biostudies-literature
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Pressure Regulated Volume Control (PRVC): Set it and forget it?
Singh Gurkeerat G Chien Christina C Patel Sharad S
Respiratory medicine case reports 20190308
Pressure-regulated volume control (PRVC) is a mode of ventilation in which the ventilator attempts to achieve set tidal volume at lowest possible airway pressure. This mode of ventilation is being commonly used as the initial mode of ventilation in many intensive care units. We describe two cases where this adaptive mode of ventilation became maladaptive leading to patient-ventilator dyssynchrony. ...[more]
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Project description:IntroductionDigital trials are a promising strategy to increase the evidence base for common interventions and may convey considerable efficiency benefits in trial conduct. Although paediatric intensive care units (PICUs) are rich in routine electronic data, highly pragmatic digital trials in this field remain scarce. There are unmet evidence needs for optimal mechanical ventilation modes in paediatric intensive care. We aim to test the feasibility of a digital PICU trial comparing two modes of invasive mechanical ventilation using carbon dioxide (CO2) control as the outcome measure.Methods and analysisSingle-centre, open-labelled, randomised controlled pilot trial with two parallel treatment arms comparing pressure control versus pressure-regulated volume control. Patients are eligible if aged <18 years, weighing >2 kg, have an arterial line and require >60 min of mechanical ventilation during PICU hospitalisation at the University Children's Hospital Zurich. Exclusion criteria include cardiac shunt lesions, pulmonary hypertension under treatment and intracranial hypertension. CO2 is measured using three methods: end-tidal (continuous), transcutaneous (continuous) and blood gas analyses (intermittent). Baseline, intervention and outcome data are collected electronically from the patients' routine electronic health records. The primary feasibility outcome is adherence to the assigned ventilation mode, while the primary physiological outcome is the proportion of time spent within the target range of CO2 (end-tidal, normocarbia defined as CO2 ≥ 4.5 and ≤ 6 kPa). Both primary outcomes are captured digitally every minute from randomisation until censoring (at 48 hours after randomisation, extubation, discharge or death, whichever comes first). Analysis will occur on an intention-to-treat basis. We aim to enrol 60 patients in total. Recruitment started in January 2024 and continued for 9 months.Ethics and disseminationThis study received ethical approval from the Cantonal Ethics Commission of Zurich (identification number: 2022-00829). Study results will be disseminated through publication in a peer-reviewed journal and other media like podcasts.Trial registration numberNCT05843123.
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Project description:PurposeThe aim of this study was to compare the effect of a pressure-controlled strategy allowing non-synchronised unassisted spontaneous ventilation (PC-SV) to a conventional volume assist-control strategy (ACV) on the outcome of patients with acute respiratory distress syndrome (ARDS).MethodsOpen-label randomised clinical trial in 22 intensive care units (ICU) in France. Seven hundred adults with moderate or severe ARDS (PaO2/FiO2 < 200 mmHg) were enrolled from February 2013 to October 2018. Patients were randomly assigned to PC-SV (n = 348) or ACV (n = 352) with similar objectives of tidal volume (6 mL/kg predicted body weight) and positive end-expiratory pressure (PEEP). Paralysis was stopped after 24 h and sedation adapted to favour patients' spontaneous ventilation. The primary endpoint was in-hospital death from any cause at day 60.ResultsHospital mortality [34.6% vs 33.5%, p = 0.77, risk ratio (RR) = 1.03 (95% confidence interval [CI] 0.84-1.27)], 28-day mortality, as well as the number of ventilator-free days and organ failure-free days at day 28 did not differ between PC-SV and ACV groups. Patients in the PC-SV group received significantly less sedation and neuro-muscular blocking agents than in the ACV group. A lower proportion of patients required adjunctive therapy of hypoxemia (including prone positioning) in the PC-SV group than in the ACV group [33.1% vs 41.3%, p = 0.03, RR = 0.80 (95% CI 0.66-0.98)]. The incidences of pneumothorax and refractory hypoxemia did not differ between the groups.ConclusionsA strategy based on PC-SV mode that favours spontaneous ventilation reduced the need for sedation and adjunctive therapies of hypoxemia but did not significantly reduce mortality compared to ACV with similar tidal volume and PEEP levels.
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