A case report of a patient with a significant
smoking history who had a respiratory arrest
by
Helen Trainor
Trainee Anaesthetic Technician
Introduction
This case study will look at the anaesthetic management of a patient who had a respiratory
arrest in theatre at extubation following elective endovascular aneurism repair. The study
will focus on management of events, factors contributing to them and the role of the
trainee anaesthetic technician. As the patient had been discharged from the hospital at the
time of this case study, I was advised by the Consultant Anaesthetist who managed the case
to telephone the patient directly to ask for his permission to write about his surgery.
The
patient was very happy to help and understood that no personal information which would
identify him to friends or family would be included. I offered to send him a copy of the case
study but he said he did require me to do this.
Case presentation
The patient was a 63 year old male with a significant health history. He had a 50 pack year
smoking history, chronic obstructive pulmonary disease (COPD) requiring daily
bronchodilators, a productive cough that he explained was normal for him; hypertension
and previous syncopal episodes. His normal oxygen saturation was 93% on air. He was on
various medications for his cardiovascular and respiratory disease, including digoxin,
flixotide, carvedilol, symbicort and paracetamol, and he is non-compliant with all of these.
His airway assessment showed that he had a Mallampati score of 2 suggesting he would not
be a difficult intubation (Hamlin et al, 2009).
His ASA (American Society of
Anaesthesiologists) score was 4, which means “a patient with severe systemic disease that is
a constant threat to life” (Gwinnutt, p11, 2008).
The ASA score is the most widely used
scale for estimating risk in anaesthesia.
The anaesthetic plan was discussed with the anaesthetist prior to patient arrival and was as
follows: general anaesthesia (GA) with an endotracheal tube (ETT); 14 gauge intravenous
cannulae, arterial line and a 5 lead electrocardiogram (ECG) in addition to routine set up.
The anaesthetic machine had been checked to Level 3 standard as it was the 2nd case of the
day.
Given the patient’s COPD, I also ensured the salbutamol was readily available and
asked the anaesthetist if they wanted to have blood available because of the risk of
bleeding.
The plan was to intubate the patient for the procedure because of its long duration and
because this was the best way to maintain his airway with the patient’s decreased
respiratory compliance and need for carefully managed controlled ventilation. A large bore
intravenous cannula and arterial line were inserted.
The cannula was placed as a safety
precaution in case of severe hypotension due to the patient’s cardiovascular instability and
to manage any intraoperative haemorrhage.
The arterial line was placed so that his
cardiovascular status could be assessed continually given his hypertension and the risk of
bleeding. It also facilitated frequent arterial blood gases (ABGs) and the shape of the
waveform gives additional information regarding myocardial contractility and other
haemodynamic variables, which were essential for this patient (Gwinnutt, 2008).
The anaesthetist asked me to pre-oxygenate the patient prior to induction.
I was very
careful to ensure a good seal so that the patient did not entrain air and dilute the oxygen. I
recognised the importance of good pre-oxygenation for this patient given his lung disease
and reactive airways.
Pre-oxygenation is essential because it replaces the nitrogen with
oxygen, increasing the length of time that a patient can be apnoeic during intubation
without becoming hypoxic (Gwinnutt, 2008). The patient was easy to bag-mask ventilate
and intubation was a Grade 1 view on the Cormack and Lehane grading system (Dhara,
2003). I secured the ETT, taped the eyes shut, inserted a temperature probe and applied a
Bair Hugger for maintenance of body temperature. In addition, intravenous fluids had been
primed through a fluid warmer to prevent further heat loss from conduction.
The patient was placed in supine position for the procedure with his arms at a 90 degree
angle secured safely on armboards. The surgery went well with minimal blood loss and the
patient’s anaesthetic was relatively stable throughout.
His blood pressure was labile
however and so I was required to take regular ABGs so that the anaesthetist could titrate
the anaesthetic according to the clinical picture.
A metaraminol infusion was used to
manage the patient’s blood pressure.
At the end of the procedure the patient was extubated smoothly and was maintaining his
own airway with oxygen therapy via a Hudson mask. He was about to be transferred to
recovery when he went into acute respiratory failure.
This was recognised when the
anaesthetist noticed the patient had stopped breathing and his oxygen saturations were
beginning to fall; getting down to 69% at one stage.
I recognised straight away that I
needed extra help from the trained technician, so requested their assistance.
I responded to the situation by quickly passing the anaesthetist the breathing circuit with
the face mask on it and turning on oxygen at the flowmeter. The anaesthetist had some
difficulty ventilating the patient’s lungs despite attempting to help the situation by trying
both an oral and nasopharyngeal airway.
The anaesthetist also called for another
consultant to come and review the case but insisted that the emergency bell was not
required to be activated at this stage.
At this time it was also noticed that the patient’s abdomen was starting to distend due to
gas inflating the stomach rather than the lungs. The decision was then made to re-intubate
the patient as quickly as possible to ensure oxygenation.
In anticipation of this I had
already prepared an ETT and placed the suction ready for use. This went smoothly but bag
mask ventilation was still difficult despite the ETT but the anaesthetist found that slow,
gentle breaths enabled adequate oxygenation.
After a number of breaths, the patient’s
saturations went up to 94% which was acceptable given his lung disease.
At this point a mobile chest x-ray was ordered to rule out pneumothorax which was a
potential risk of the endoluminal procedure.
This proved to be negative.
Instead the
picture presented asymmetrical pulmonary oedema. This can result in right heart failure
and so the anaesthetist decided to place a central line to monitor the patient’s right atrial
pressures.
It was also useful for the administration of fluids and drugs postoperatively so
the equipment was set up quickly so that this could be inserted without delay.
Management and Outcome
The patient was ventilated in theatre until it was considered safe for transfer to occur. Once
his oxygen saturation remained within acceptable levels and his hypotension was under
control, the patient was considered safe for transfer to the Cardiovascular Intensive Care
Unit (CVICU). Originally he had been destined for the Post Anaesthetic Care Unit but it was
agreed that he required an extended period of close monitoring and individually tailored
ventilation until he was able to be safely extubated.
To transfer the patient safely, a transport trolley was organised to facilitate continued
ventilation and cardiovascular monitoring during the transfer.
The equipment on the
trolley was checked to ensure it was present and that the suction and ventilator functioned
correctly.
The patient’s airway equipment and suxamethonium were added to the trolley
in case of accidental extubation during transfer.
My role at this time was to ensure a seamless changeover from machine monitor to
transport monitor – minimising the time that readings were lost. In addition to this, IV lines
were placed on an IV pole attached to the bed taking care not to tangle them or accidentally
pull them out. I checked the Ambubag in preparation for manual ventilation during transfer
as this was the anaesthetist’s preference.
I also rang the CVICU to warn them that we
were on our way to the unit. It is vital that the standard of care and monitoring during
transfer is to the same standard as in the operating theatre (OR) and that the staff
transferring the patient are well informed about the patient’s specific risks (Al-Shaikh &
Stacey, 2009). Transfer was uneventful and the patient safely delivered to the CVICU.
Intensive Care Specialists decided that the patient required a tracheostomy to facilitate
effective long-term ventilation. Aitkenhead (2001) states that this is more comfortable for
the patient and easier to manage for the staff. I followed up the patient’s care with CVICU
staff once I had decided to write about my experience with this patient.
I was informed
that the tracheostomy was performed electively and the patient was artificially ventilated
until he was able to maintain his own airway and a second respiratory arrest considered
unlikely. At discharge he was transferred back to his local hospital for further care before
being sent home. When I spoke to the patient to gain consent for this case study he said
that he had recovered and was doing well at home.
Discussion
After discussion with the anaesthetist when the patient had left theatre he concluded that
the reason for the patient’s respiratory failure were unknown. Possible contributing factors
were that the patient had a known compromised respiratory function due to his COPD.
COPD is defined as lung disease characterized by chronic obstruction of lung airflow that
interferes with normal breathing and is not fully reversible. The symptoms of COPD are
cough, fatigue, recurrent respiratory infections, dyspnoea that gets worse with mild activity,
trouble catching breath and wheezing (Hadjiliadis, 2011).
The patient’s long smoking
history will have contributed to his COPD because the smoke and tar kills lung tissue, which
results in a decrease in the area available for gaseous exchange. Further to this, the lungs
produce excessive mucous which plugs the alveoli, further reducing gas exchange, and
predisposes to further infections because the mucous and damaged cells provides a
reservoir to bacteria. The longer you smoke, the more likely you are to develop COPD.
(Hadjiliadis, 2011).
In addition to this, and possibly as a result of the COPD, the patient also had pre-existing
hypertension. Hypertension is a risk factor for cardiovascular complications after
anaesthesia and surgery as it puts strain on the heart. Patients with hypertension generally
exhibit exaggerated hypotension after induction of anaesthesia and excessive pressor
response to stresses such laryngoscopy and intubation, surgical incision and extubation
(Gwinnutt, 2008). This is exactly what happened with this patient. He became severely
hypotensive (70/20) at the time of extubation and required a metaraminol infusion to
stabilise his blood pressure.
Further to this, the patient was non-compliant with all of his medication and therefore
presented for surgery in a less than optimal state of health. Long-term treatment of
hypertension returns vascular reactivity to more normal levels thereby improving
cardiovascular stability, so the patient would have been more haemo-dynamically stable
throughout his procedure if he had been compliant with medication (Mayell, 2006).
Conclusion
This case demonstrates the events of a respiratory arrest, management of a compromised
patient, and the need for the trainee anaesthetic technician (AT) to be prepared for any
anticipated or unanticipated events in the theatre environment, including getting
experienced help as soon as possible from the trained technician.
I chose to write about
this case in particular because it was very eventful, a good learning experience for a trainee
AT but especially because it demonstrates how much smoking can have a detrimental effect
on health.
This patient was only 63 which I think is relatively young given that people can
live into their 80s and 90s today.
As a trainee AT, it was particularly interesting to witness
a real-life situation of how much this patient’s smoking history impacted on his safety during
his anaesthetic and recovery.
As a result of this experience, I will always be alert to the
potential problems that can compromise patient safety when they have a history of heavy
smoking.
References
Aitkinhead, A., Smith, G. (2001). Textbook of Anaesthesia 4th Ed. Churchill Livingstone: UK.
Al-Shaikh, B., Stacey, S. (2009). Essentials of anaesthetic equipment Third Edition. Churchill
Livingstone: UK.
Gwinnutt, C. (2008). Clinical Anaesthesia lecture notes 3rd edition. Wiley-Blackwell: UK.
Hadjiliadis, D. (2011). Chronic obstructive pulmonary disease. Retrieved 2012 September 5
from http://www.nlm.nih.gov/medlineplus/ency/article/000091.htm
Hamlin, L., Richardson-Tench, M., Davies, M. (2009). Perioperative nursing and introductory
text. Mosby-Elsevier: Australia.
Mayell, A. (2006). Hypertension in anaesthesia. Retrieved 2012 September 5 from
http://www.frca.co.uk/article.aspx?articleid=100656