PATIENT MONITORING

93% (1,688/1,818) responded to the question relating to critical events. From the review
of cases it is likely that these were under-reported (Table 22) or undiagnosed, possibly reflecting a deficiency in monitoring. Nevertheless, from the questionnaires, 4% (68/1,688)
of patients suffered from hypoxaemia during the procedure.

The type of monitoring used should be determined by the procedure and physical status
of the patient. Respondents were asked to state the monitoring used during the procedure. This question was answered in 94% (1,701/1,818) of cases. There should always be a record of monitoring used during endoscopy, particularly when sedation is used. A summary of monitoring is presented in Table 23.

NCEPOD advisors were asked to provide an opinion on deficiencies in monitoring in cases where there was sufficient information for them to assess. Monitoring of the patient during the procedure was considered deficient in 27% (377/1,398) of cases.

Pulse oximetry (back to top)

The question on patient monitors used during the procedure was completed in 1,701
cases. Monitoring by pulse oximetry was performed during endoscopy in 98% (1,668/1,701)
of patients. On review, the advisors thought monitoring pulse oximetry was specifically indicated in a further 27 cases. The BSG guidelines on the provision of endoscopy services recommend that pulse oximetry should be available in all rooms⁶. Pulse oximetry is
a simple, non-invasive monitor and evidence from this report suggests that it is widely available for endoscopy patients; the chapter entitled organisational issues reports that
99% of hospitals had access to pulse oximetry in every room in their endoscopy unit.
It was used with relatively few exceptions, but it should be used for all therapeutic and diagnostic endoscopies.

Electrocardiography (ECG) (back to top)

In this sample, 23% (384/1,701) of patients received continuous ECG monitoring during
the procedure. This was considered low in a sample where 38% (639/1,701) of patients
had known cardiac disease and 86% (1,458/1,701) were ASA 3 or poorer. On review,
the advisors thought ECG monitoring was indicated in a further 345 cases where it was
not used.

Why was ECG monitoring not used?

There is evidence that despite endoscopy being, in general, a minor low risk procedure
it can affect cardiac function. In a study of patients with stable coronary heart disease undergoing gastroscopy 42% developed Holter monitoring, evidence of silent myocardial ischaemia⁷ and in another study of patients with heart disease aged 80 years or older, upper GI endoscopy induced an increased number of ventricular ectopics⁸. ECG monitoring enables the detection of life threatening arrhythmia and ST segment changes and the person responsible for monitoring the patient must be sufficiently trained to detect such abnormalities. The factors that should be considered when deciding on ECG monitoring
are cardiovascular disease, ASA status and the potential for haemodynamic instability.
The guidelines of the Academy of Medical Royal Colleges¹ state that monitoring of blood pressure and ECG may not be necessary in young healthy patients, but is essential in
older patients, especially if there are any cardiovascular problems. However, an ECG monitor should be available in all endoscopy rooms and any patient with a history of cardiac problems or haemorrhage must receive ECG monitoring.

Automatic blood pressure monitoring (back to top)

Automatic blood pressure monitoring was used in 43% (729/1,701) of patients during the procedure. On review, the advisors thought automatic blood pressure monitoring was indicated in a further 231 cases where it was not used. Although it is not an invasive monitor, many patients find automatic blood pressure monitoring unpleasant, particularly when it is first applied when the inflation pressure is high.

All endoscopy rooms should have an automatic blood pressure machine. Automatic blood pressure monitoring should be used in any patient whose condition including comorbidities makes hypotension likely. This includes haemodynamic instability and a recent severe
GI bleed.

Supplemental oxygen (back to top)

Oxygen should be given during all endoscopies² as it dramatically reduces the incidence
of hypoxaemia⁹. Table 24 gives details of oxygen administered in the sample.

Hypoxaemia can occur during upper GI endoscopy with or without sedation, particularly
in those with pre-existing respiratory disease, hepatic cirrhosis, obesity, advanced age or undergoing an emergency procedure^{9 10 11 12}. It can also occur during colonoscopy with sedation¹³. Moreover hypoxaemia is common. For example, in a study of non-sedated patients undergoing upper GI endoscopy, 24% had a SpO2 of 90% to 94% and a further 6.5% had a SpO2< 90%¹⁰. When sedation is used, the incidence of hypoxaemia is higher. In a study of patients undergoing sedated upper GI endoscopy, SpO2<94% was detected
in 47%⁹ and in a study of patients undergoing sedated colonoscopy, hypoxaemia was detected in 45% (8/18)¹³. However, even with supplemental oxygen, patients can become hypoxic and therefore pulse oximetry should still be used.