Tracheal tube cuff pressure monitoring: Assessing current practice in critically ill patients at Chris Hani Baragwanath Academic Hospital

Abstract

Cuffed tracheal tubes are used to prevent loss of tidal volume during positive pressure ventilation, minimise pulmonary aspiration of gastric and oral secretions, facilitate respiratory monitoring and, in the paediatric population, reduce the need for repeated laryngoscopy due to incorrect tube size. [1][2][3] These goals are achieved by appropriate cuff inflation. Cuff pressure (CP) should be >25 cmH 2 O to prevent aspiration and <30 cmH 2 O to avoid damage to surrounding structures. [4,5] Obstruction to blood flow occurs when CP exceeds capillary perfusion pressure, resulting in ischaemia of the tracheal mucosa. Blood flow is impeded at CP ≥30 cmH 2 O in normotensive adult patients, with total obstruction of flow occurring at CP ≥50 cmH 2 O. [5] No paediatric studies have been performed to assess capillary perfusion pressure or the CP at which tracheal capillary blood flow is impeded. The extent of damage from increased CP is related to the absolute pressure exerted by the cuff and the duration of this pressure (mucosal damage is noted to occur within 15 minutes of exposure to high pressures), with a greater contribution being from the absolute pressure. [5,6] Injuries from high CP range from mucosal ulceration to tracheo-oesophageal fistula. [6,7] Low CPs are also associated with risks, including the development of ventilator-associated pneumonia secondary to aspiration and compromised ventilation resulting from loss of positive pressure. [1,8] Internationally accepted consensus guidelines for optimal CP range and frequency of measurement are lacking. [9] A local nursing guideline suggests a CP range of 25 -30 cmH 2 O. [10] The 2015 American Heart Association Pediatric Advanced Life Support guidelines recommend using the manufacturer's specification for appropriate CP in children <9 years and suggest a reference range of 20 -25 cmH 2 O. [11] CP should be measured using a manometer or pressure transducer, as techniques such as digital palpation and the minimal leak technique Background. Intubated patients with a high tracheal tube cuff pressure (CP) are at risk of developing tracheal or subglottic stenosis. Recently an increasing number of patients have presented to our hospital with these complications. Objectives. To determine the frequency of tracheal tube CP measurements and the range of CP and to explore nursing knowledge regarding CP monitoring. Methods. Frequency of CP measurement was assessed using a prospective chart review, followed by an interventional component. In the final stage nurses completed a self-administered questionnaire. Results. A total of 304 charts from 61 patients were reviewed. Patients' ages ranged from 1 to 71 years, with a male preponderance (1.5:1). The majority of charts (87%) did not reflect a documented CP measurement and only 12 charts showed at least one measurement per shift. Only 17% of recorded CPs were within the recommended range; 59% were too low. The questionnaire was completed by only 51% of the 75 respondents. Nursing experience ranged from 3 to 35 years and 92% of ...

Knowledge acquisition and retention among nurses after an educational intervention on endotracheal cuff pressure

“…However, the characteristics of the nurses and the study setting were similar to those in most ICUs in Malaysia 38 . Second, this study only reported on knowledge acquisition but did not observe the changes in actual practice as an outcome of learning, so further studies to access the impact of education intervention on practice and compliance are suggested as knowledge acquisition may not guarantee safe practice 16,39 …”

“…These recommendations are also part of the preventive measures emphasized in the VAP prevention guidelines 10,11 . Despite the existence of such guidelines, evidence shows that variation in cuff maintenance practices and compliance with such guidelines are still suboptimal in some of the ICUs in developed countries like the United States, 6 Australia, and New Zealand 12,13 and in developing countries like Pakistan, 14 Sri Lanka, 5,15 and South Africa 16 …”

“…Variations in practice were noted in the frequency of monitoring, 14,17 technique of cuff pressure measurements, 5,12,18 and documentation 16 . Diversity in the frequency of monitoring endotracheal cuff pressure among nurses and ICUs was reported in international literature, with some monitoring every 2 to 4 hours; some every 6 to 12 hours; and others only if the need arose, such as when air leakage was noted 12,17,18 .…”

Pulmonary complications and respiratory management in neurocritical care: a narrative review

“…The inflated cuff of the endotracheal tube is designed to prevent microaspiration; thus, the cuff pressure should be at a moderate level at 20 to 30 cm of water, as air leakage or aspiration occurs when it is too low, and tracheal or subglottic stenosis occurs when it is too high. [ 5 , 76 , 77 ] In NCC patients, the cuff pressure may decline with extubation and the transition to a prone position. [ 78 ] In addition, the high incidence of pneumonia further emphasized the necessity of determining and monitoring cuff pressure.…”

Goldilocks and endotracheal tube cuff pressure management: Not too high, not too low. Just right …

“…Plato suggested that 'human behaviour flows from three main sources: desire, emotion, and knowledge.' If, as is suggested by Khan et al, [8] we have the knowledge, then our behaviour towards cuff pressure measurement must be for the lack of desire and emotion in this regard. The desire to do or react to something is a function of its immediacy, its seriousness and the degree to which we connect with it.Our challenge is to effect a behaviour change in this regard.…”