Continuous vs Intermittent Monitoring of Respiratory and Heart Rate in Relation to Length of Stay

Tachypnea is not just a sign of ventilatory problems with hypoxia, but also a precursor of sepsis, metabolic acidosis and severe pain reflecting its role as an indicator of severe derangement in many body systems. A high respiratory rate has been shown to be the most reliable vital sign to predict clinical deterioration, cardiac arrest and is even associated with higher mortality rates. Despite this, it is the vital parameter most neglected; poorly documented or not recorded at all. Studies have shown that respiratory rate is measured in less than half of cases consequently jeopardizing patient safety. The lack of understanding why respiratory rate is important and its superiority to pulse oximetry in predicting clinical deterioration may be one of the reasons why it is not measured accurately.

Badawy and colleagues stated in their study "Is everyone really breathing 20 times a minute?" that respiratory rate was inaccurately recorded and had little variation in the recordings, even in patients with cardiopulmonary compromise, findings that's been supported with later studies. Respiratory rate has traditionally not been objectively measured in general wards, but instead calculated manually over 30 seconds or a minute. This could be changed by new wireless monitoring technology. A recent large study showed that continuous measured respiratory rate together with heart rate and age in a clinical deterioration model outperformed traditional early warning scores in predicting ICU admission.

The present study evaluates heart rate and respiratory rate measured continuously with a new wireless sensor as compared to standard care, with manually measured spot checks by nurses on general wards.

Inclusion criteria

• ≥ 18 years of age
• planned to go through a major high-risk surgery
• American Society of Anesthesiologists (ASA) class 2-4 due to present comorbidities
• planned to stay in the postoperative high dependency unit for >12hours where they also would have wired continuous monitoring.

Exclusion criteria

• pregnancy
• presence of implantable defibrillator or pacemaker
• allergy to skin adhesives