Interobserver variability in determination of anaerobic threshold by cardiopulmonary exercise testing

Abstract

MethodsFifty-two emergency caesareans were assessed over a calendar month. A questionnaire was completed per delivery by the obstetric, midwifery and anaesthetic staff involved. Data analysis was via Excel spreadsheets. ResultsFor category-1 deliveries, 100% of cases were communicated with the anaesthetist within 2 min of the decision to deliver. For category-2 deliveries, the anaesthetist was informed within 2 min for only 50% of cases. The mean (range) communication times was 6.3 min (0-28 min). The person communicating with the anaesthetist should ideally be an obstetrician of appropriate seniority. In category-1 sections, this was only achieved in 33% of cases. Category-2 sections achieved this in 38% of cases. DiscussionThis audit shows that anaesthetists are not promptly notified regarding emergency caesarean sections, and are often not notified by an obstetrician of appropriate seniority when these cases arise. After the decision is made to deliver a woman by caesarean section, the most senior obstetrician should contact the duty anaesthetist promptly [1]. This will allow discussion of the patient's clinical issues, and improve anaesthetic assessment and management.

Test–retest reliability of the oxygen uptake efficiency slope in surgical patients

“…With exercise, the requirement for ventilation increases with oxygen uptake and in patients with cardiorespiratory disease, greater ventilatory effort is required as oxygen uptake rises; this is manifest as a decrease in the oxygen uptake efficiency slope. In addition to not requiring maximal effort, the determination of the oxygen uptake efficiency slope from the respiratory data requires no subjective interpretation of the exercise data [7,15], in contrast to the anaerobic threshold, which may be difficult to identify [16,17] and is subject to observer error [18].…”

“…Although the use of anaerobic threshold has been advocated for risk stratification [4], it has acknowledged weaknesses, such as interpretation error in medical [5,29,33,36] and surgical [18,37] patients, and even complete failure to identify a value in 12-23% of tests in non-surgical patients [8,9,17,23,26]. There are a number of physiological flaws, which have recently been well summarised [38], that could account for some of these problems.…”