Table 6

 AB COVER CD algorithm

Total sample included *E/S, epidural or spinal block cases (98 epidural, 91 spinal, 4 combined, 3 caudal); †BrPl, brachial plexus block cases (12 axillary block, 5 interscalene block, 3 supraclavicular block, 1 not stated); ‡Oph, ophthalmic block cases (9 peribulbar, 9 retrobulbar, 5 not stated).
BBreathing (3 cases)
 Apnoea during LSCS (1), delayed respiratory depression (1)2
 Laryngeal nerve palsy1
CCirculation (pulse)
 Although some of the cases of hypotension and dysrhythmia may have been detected by feeling the pulse volume, these are included at the C stage of CD in the algorithm as they would be detected during the systematic check of the circulation (see Circulation, below)
Colour (4 cases)
 Hypoxia during sedation21
 Hypoxia during positioning1
OOxygen supply to patient
Oxygen analyser
Vaporisors (4 cases)
 Vaporiser left on21
 Overfilled vaporiser1
EEndotracheal tube
RReview monitors (8 cases)
 Blood pressure measurement: inappropriate cuff application (1); not turned on (1); failure to measure (1); erroneous reading (1)4
 Capnograph: CO2 water trap missing1
 Electrocardiogram: incorrect rate1
 No foetal heart monitor1
Review equipment (8 cases)1
 Intravascular air1
 Surgeon punctured intravenous line1
 Leaking Haemaccel flask1
 No IV access – forgotten1
 Burn via diathermy1
 Drug fridge turned off1
 Wrong table1
 Fell off table1
CCirculation (60 cases)
 Hypotension (25 spinal cases including 4 deaths, 10 epidural cases including 2 deaths, 1 brachial plexus case)351
 Bradycardia (7 spinal, 5 ophthalmic cases)75
 Hypertension (3 spinal)3
 Myocardial infarction (2 spinal, 1 epidural)3
 Ventricular tachycardia (1 spinal)1
 Supraventricular tachycardia (1 spinal, 1 ophthalmic)11
 Arrhythmia (1 brachial plexus)1
 Left ventricular failure (2 ophthalmic)2
DDrugs (22 cases)
Wrong drugSyringe swap5
Wrong local anaesthetic2
Wrong concentration6
Drug not given2
Communication problemCommunication about subcutaneous heparin1
Communication about intrathecal morphine1
Wrong routeInadvertent epidural metaraminol2
Inadvertent epidural ranitidine1
Epidural infusion connected to intravenous infusion2