Embedded Files
Page 6
Evidence-Based Practice of Weaning from Ventilator: A Review Saikat Sengupta1†, Chandrashish Chakravarty2 , A. Rudra3 1 Professor, Apollo Gleneagles Hospitals, Kolkata, India 2 Consultant, Apollo Gleneagles Hospitals, Kolkata, India 3 Emeritus Professor, KPC Medical College & Hospitals, Kolkata, India Edited by: Dr. Niraj Niranjan, Consultant Anaesthetist, University Hospital North Durham, UK † Corresponding author e-mail: saikatsg@gmail.com Published 6 February 2018 KEY POINTS Mechanically ventilated patients should have a daily assessment relating to their ability to be weaned from ventilatory support. A spontaneous breathing trial helps to identify patients who may be successfully extubated and the available evidence would suggest this should be in the form of an intermittent T-piece or a minimal-level pressure support trial for 30 minutes. Noninvasive ventilation can have a role in reducing the duration of mechanical ventilation in chronic obstructive pulmonary disease (COPD) patients but should not be used to treat extubation failure. INTRODUCTION Liberation from mechanical ventilation in intensive care unit (ICU) patients often appears to be a blend of art and science. The science component exists in identifying clinical indicators of improving or recovering physiology whilst clinical judgement still plays a crucial role in selecting those who can breathe without support. Some patients wean quickly and uneventfully and, in this respect, their management may be simple. For other patients, this process may be long and protracted. There has been a significant volume of work on weaning since the early 1990s but there is a lack of reproducibility and predictive value in the evidence. WHAT DO WE MEAN BY WEANING? Weaning from ventilator comprises 2 separate aspects: 1. Liberation from the ventilator and the mechanical support that it offers. 2. Removal of the artificial airway. IDENTIFYING PATIENTS SUITABLE FOR WEANING Many studies show that a spontaneous breathing trial (SBT) is a good method of identifying patients ready to be weaned from mechanical ventilation. This is commonly done using a pressure support ventilation (PSV) mode or a T-piece trial. If the patient can maintain gas exchange at minimal levels of pressure support (usually 5 to 10 cm H2O) or when on the T-piece, the feasibility of weaning from mechanical ventilatory support can be assessed. An online test is available for self-directed Continuous Medical Education (CME). It is estimated to take 1 hour to complete. Please record time spent and report this to your accrediting body if you wish to claim CME points. A certificate will be awarded upon passing the test. Please refer to the accreditation policy here. Subscribe to ATOTW tutorials by visiting www.wfsahq.org/resources/anaesthesia-tutorial-of-the-week ATOTW 372 — Evidence-Based Practice of Weaning from Ventilator: A Review (6 February 2018) Page 1 of 6 I N T E N S I V E C A R E Tutorial 372 TAKE ONLINE QUIZ Modifiable factors that can hinder progress towards extubation also need to be sought and addressed, preferably with a daily screen by the intensive care team. In an analysis of weaning protocols, Ely suggested the ‘WHEANS NOT’ mnemonic to aid clinicians in identifying such issues:1 Wheeze (especially COPD and asthma) Heart disease and fluid overload Electrolytes and metabolic derangement Anxiety and delirium Neuromuscular disease and weakness Sepsis Nutrition insufficiency Opiates and other sedatives Thyroid disease Finally, a protocol-driven team approach has been shown to be more successful than a physician-driven approach.2 WEANING INDICES Multiple criteria have been used to assess readiness to wean. Subjective criteria include tachypnoea, diaphoresis, haemodynamic stability, delirium, and other signs of increased work of breathing. Integrated indices include the compliance, resistance, oxygenation, and pressure index; the simplified weaning index; and the rapid shallow breathing index (RSBI).3 Many studies have demonstrated the
Google Sites
Report abuse