China
Africa
Explore chapters and articles related to this topic
Patient Transfer
Published in Ian Greaves, Keith Porter, Jeff Garner, Trauma Care Manual, 2021
Ian Greaves, Keith Porter, Jeff Garner
Given that a significant number of trauma patients have underlying lung injury and pulmonary contusion, patients should have a Vt of <6 mL/kg and a PEEP of 5 with a peak pressure below 30 cmH2O. It should be noted that low volume ventilation will allow PaCO2 to rise; in lung-protective ventilation this is tolerated if the patient’s pH remains above 7.25. This is known as permissive hypercapnia. In patients with traumatic brain injury the need to protect the brain must be weighed against the need to protect the lungs. It should be avoided in patients with clearly raised ICP.
Intensive Care Medicine
Published in Elizabeth Combeer, The Final FRCA Short Answer Questions, 2019
Ventilatory: aim to maintain adequate gas exchange until cellular damage resolves without causing further lung injury due to baro-, volu-, atelec- and biotrauma: PEEP.Tidal volume 6 ml/kg.Permissive hypercapnia.Accept PaO2 sufficient to adequately oxygenate tissues.Keep peak pressure under 30 cm H2O.Minimise the difference between peak pressure and PEEP.Recruitment manoeuvres: no proven survival benefit.Prone positioning.
Recognition and Management of the Sick Child
Published in John C Watkinson, Raymond W Clarke, Christopher P Aldren, Doris-Eva Bamiou, Raymond W Clarke, Richard M Irving, Haytham Kubba, Shakeel R Saeed, Paediatrics, The Ear, Skull Base, 2018
Julian Gaskin, Raymond W. Clarke, Claire Westrope
Strategies used in PICU are aimed at restoring and maintaining normal body functions. In essence, this is done by providing adequate oxygen and energy supplies to all organs and tissues to maintain their function. Oxygen is delivered to the body via respiration and delivered to the tissues by being carried in the blood (mostly via haemoglobin) and so normal tissue function is dependent on adequate oxygen supply to the lungs (ventilation) and adequate blood supply to the tissues (cardiac output and circulation). The principles of ventilation are largely generic, regardless of the large variety of underlying pathologies leading to the child needing ventilation. Ventilation ensures adequate pulmonary oxygen supply and carbon dioxide removal, but it may cause injury to the lungs by barotrauma/volutrauma and alveolar collapse, or by direct oxygen toxicity. Regardless of whether the lungs are normal or diseased, a ‘lung-protective’ ventilator strategy should be used. Pressure, volume and oxygen settings can be minimized and mild or ‘permissive’ hypercapnia and hypoxia is now accepted. In PICU PIP (peak inspiratory pressures) ≥30 cm H20, expiratory tidal volumes ≥10 mL/kg and inspired oxygen concentration (FiO2) ≥60% are all associated with ventilator-induced lung injury.
Optimizing Physiology During Prehospital Airway Management: An NAEMSP Position Statement and Resource Document
Published in Prehospital Emergency Care, 2022
Daniel P. Davis, Nichole Bosson, Francis X. Guyette, Allen Wolfe, Bentley J. Bobrow, David Olvera, Robert G. Walker, Michael Levy
Hyperventilation is generally harmful but unfortunately common in prehospital ventilation (33). For most patients, achieving eucapnia with a target PaCO2 ∼40 mmHg is reasonable. End-tidal CO2 may not accurately reflect PaCO2 in critically ill and injured patients but can help avoid excessive ventilation rates (57). These are associated with inadvertent hypocapnia and elevated intrathoracic pressures, which may compromise cardiac output or result in lung injury via barotrauma. Patients with traumatic brain injury experience decreased cerebral blood flow, with increased ventilation rates leading to worse outcomes. Controversy exists for use of mild hyperventilation in patients with impending herniation; this is addressed elsewhere in this compendium (60). Patients with metabolic acidosis but without brain injury may require a lower PaCO2 target to provide partial respiratory alkalosis unless this relative hyperventilation results in hypotension. Patients with acute respiratory distress syndrome (ARDS) or multi-organ dysfunction syndrome benefit from low tidal volume ventilation and permissive hypercapnia to avoid the adverse systemic and/or pulmonary effects of positive-pressure ventilation.
Hypothesis: Fever control, a niche for alpha-2 agonists in the setting of septic shock and severe acute respiratory distress syndrome?
Published in Temperature, 2018
F. Petitjeans, S. Leroy, C. Pichot, A. Geloen, M. Ghignone, L. Quintin
By contrast, cooling febrile CCU patients reduces VO2 by ≈8–10% per °C [14]. In paralyzed sedated patients under controlled mechanical ventilation, surface cooling (39.4±0.8 °C to 37.0±0.5) decreases VO2 (359±65 to 295±57 mL.min-1; aggregated data: −18%) [29]. In one mild shivering patient, lowering temperature to 36.2°C reduces VO2 by −39%. VCO2 is lowered (303±43 to 243±37 mL.min-1:−20%). This is relevant when low driving pressure [30] and permissive hypercapnia [31] are considered in the setting of ARDS (“protective” ventilation). Cardiac output, O2 extraction ratio2 and HR decrease (respectively: 8.4±3.2 L.min-1 to 6.5±1.8 L.min-1, 28±7 to 23±5% and 119±21 to 102±14 bpmin). Mixed venous SO2 increases from 68±8 to 71±6% (ns). Therefore, mechanical ventilation, paralysis, and cooling (from 40 to 36° C) could reduce V02 in febrile, critically ill patients by as much as 190 mL/min, lowering metabolic demand by 47%: the manipulation of VO2 is a salvage therapy in severe shock or hypoxemic respiratory failure, e.g. for febrile, mechanically ventilated patients who do not respond to sedation and antipyretics [29]. In the setting of synchronized intermittent mandatory ventilation (n = 8) or pressure support (n = 10), external cooling lowered minute ventilation (39.1 to 37°C: 14.7±1 to 13.1 ±0.9 L.min-1: −11%) and decreased energy expenditure (−12%; sedation: morphine+midazolam to Ramsay 3–4) [32]. In this trial [32], only subsets of « septic episode » or severe hypoxia were studied [32].
The acute respiratory distress syndrome: pathophysiology, current clinical practice, and emerging therapies
Published in Expert Review of Respiratory Medicine, 2018
Matthias Derwall, Lukas Martin, Rolf Rossaint
To allow for lung-protective ventilation, elevated PaCO2 levels are tolerated in patients that are not able to clear CO2 with the reduced minute ventilation settings. Tolerating the resulting elevated PaCO2 levels in these patients is called ‘permissive hypercapnia.’ Although believed to be benign or even protective, mounting evidence point to deleterious effects of elevated PaCO2 levels. Some authors revisited the physiological implications of hypercapnic acidosis recently [39], suggesting to limit PaCO2 values below 50 mmHg in Patients with moderate to severe forms of ARDS [40].