Miss T, a 28-year-old physiotherapist was admitted to hospital for a laparotomy and myomectomy.
Preoperatively, her blood pressure, respiratory rate, temperature and oxygen saturations were recorded as being within normal limits, although a tachycardia of 131 beats per minute was recorded. Her body mass index was noted to be 32. She had not previously undergone any surgical procedures or general anaesthesia and had no past medical history of note, including no allergies.
Dr R, the anaesthesiologist reviewed and examined the patient preoperatively and did not consider that there were any features to indicate the patient’s airway might be difficult to manage or that she might be challenging to intubate. He did not, however, document his review.
At the time of induction of anaesthesia, pre-oxygenation was performed before the administration of fentanyl and propofol. Rocuronium was given for muscle relaxation prior to intubation.
At laryngoscopy, a poor view of the larynx was obtained, and intubation was achieved on the second attempt, following use of a stylet. Correct placement of the endotracheal tube was considered to have been confirmed clinically. Miss T was ventilated at a rate of 12 breaths per minute with a tidal volume of 500mls. Anaesthesia was maintained with a gas mixture of 70% oxygen in air with sevoflurane.
After ten minutes of ventilation and shortly after the skin incision, a sudden drop in end tidal carbon dioxide readings and oxygen saturation was noted by Dr R, along with a loss of pulse. He did not record any observations in the period leading up to this change. External cardiac massage was performed and adrenaline was administered, resulting in the restoration of sinus rhythm after two minutes. Dr R, assuming the cause for the incident to be a dislodged endotracheal tube, extubated and then re-intubated the patient following a short period of manual ventilation.
The surgery was then performed with no further complications.
Following completion of surgery, Miss T began to breathe spontaneously but did not regain consciousness. She was transferred to the recovery room with the endotracheal tube in place. She was noted to be haemodynamically stable at this time. After 45 minutes, Miss T still had not woken up and Dr R administered naloxone, considering the administration of fentanyl at the time of induction was responsible for delayed emergence from anaesthesia. This had no effect, and Miss T was transferred to the intensive care unit for further management.
Over the following days there was little change to Miss T’s neurological status. A CT scan of the brain was recorded as being normal. She continued to breathe spontaneously and was successfully weaned from the ventilator over the course of a few days. She was reviewed by a neurologist who noted that she was breathing spontaneously and opened her eyes to painful stimuli but did not move her limbs. It was considered her presentation was in keeping with global hypoxic brain injury and she was felt to be in a persistent vegetative state.
A claim was subsequently brought against Dr R, alleging that he failed to conduct an adequate preoperative assessment of Miss T and failed to correctly intubate her. It was further alleged that there was a failure to identify misplacement of the endotracheal tube, leading to significant brain injury and persistent vegetative state, requiring lifelong care in a specialised unit.
The case was settled for over R22 million because:
- There was no record of Dr R’s preoperative assessment and therefore no evidence that an evaluation of the airway, lungs and heart was carried out as per the South African Society of Anaesthesiologists (SASA) guidelines.
- There was no signed consent form for anaesthesia.
- No consideration was given of a possible cause for the tachycardia noted prior to induction of anaesthesia.
- Although Dr R maintained that there was an end tidal carbon dioxide reading up to the point of cardiac arrest, there were no recordings of end tidal carbon dioxide up to that time, or at any time throughout the remainder of the procedure.
- There were limited records of any vital signs up to the point of cardiorespiratory collapse, meaning any deterioration in Miss T’s condition may not have been noticed.
- Given the extent of the injury sustained, and in the absence of records to indicate an alternative explanation (such as anaphylaxis), the instructed expert considered the most likely cause was a significant period of hypoxia, most likely due to a misplaced endotracheal tube and failure to ventilate the patient.
- There was also criticism (directed at both Dr R and the surgeon) of the reason why the procedure continued, especially when the collapse occurred at such an early stage.
Learning points
- Ensure an appropriate preoperative review is conducted and clearly documented.
- Ensure informed consent is taken for anaesthesia and that the clinical notes clearly reflect the discussion held.
- Ensure the use of capnography rather than relying on auscultation to confirm the position of an endotracheal tube.
- If abnormal findings are noted preoperatively there should be clear documentation of possible causes and consideration of further investigations, including whether or not the planned procedure should be postponed.
- In the event there is an untoward event occurring during anaesthesia, consideration should be given about whether it would be appropriate to continue with the surgical procedure.
- Observations of vital signs, including end tidal carbon dioxide readings, during induction and the period of anaesthesia should be taken and clearly documented.