The ABC of Maxillofacial care

The ABC of Maxillofacial care

The ABC of Maxillofacial care

Developing a standard operating procedure for the care of maxillofacial oncology patients on the intensive care unit – a trainee’s perspective from Sindy Lee

The role of the General Medical Council (GMC) as the regulator of medical practitioners is confirmed in statute by the Medical Act 1983 and its subsequent revisions [1]. The Medical Act empowers the GMC to maintain a register of approved practitioners, and to take disciplinary action against the registration of those who have failed to maintain appropriate standards, as well as governing other duties such as those related to education and standard setting.
Maxillofacial oncology patients undergo major, lengthy surgery, which is extensive and involves changes to the anatomy of the upper airway and digestive tract, as well as the use of free tissue transfer flaps with microvascular anastomoses [1].
Postoperative care of this group of patients presents many challenges, including a potentially difficult airway, a need for tight control of physiological parameters such as blood pressure and careful fluid balance. Additionally, a high level of nursing care – with special attention to the donor and recipient flap sites – is needed.

The need for standardised care
As a junior trainee working on an intensive care unit where maxillofacial oncology patients are routinely admitted for 48 hours postoperatively, I did not feel well equipped in managing their needs. This stems from having had very little experience in caring for this patient group, compounded with the tendency for patients to be admitted onto the intensive care unit in the out-of-hours period after a long operation. Our intensive care unit is placed at a district general hospital in Kent that is staffed by relatively junior trainees (mainly CT1–2) from a variety of different specialty backgrounds, including anaesthetics, core medical and emergency medicine trainees who have received limited training in airway skills.
Given the unique and complex needs of maxillofacial oncology patients and the potentially serious complications that might arise, including compromise to the airway and tissue flap, a local standard operating procedure has been developed to offer guidance on their postoperative care on the intensive care unit.

Understanding the problem
First, the common problems encountered while caring for maxillofacial oncology patients in the postoperative period was scoped out. A variety of sources were used, including a review of related Datix reports which have been submitted, focus group sessions with nursing staff and trainees, and discussion with the surgeons. The concerns from the different groups were elicited early on in the process in order to engage all parties and to tailor the guideline accordingly.
One of the recurring issues was the need to keep patients sedated to maintain the head in a strictly neutral position for at least 12 hours postoperatively. Sedation inevitably leads to hypotension secondary to the vasodilatory effects of sedative medication.
On the other hand, a reasonable mean arterial pressure is required to ensure adequate blood flow to keep the tissue flap viable. Tissue oedema in the flap should be avoided as this can impair blood flow. There is usually a normal degree of tissue swelling in the flaps in the immediate postoperative period, which curtails the scope for administration of large volumes of intravenous fluids. In addition, the use of vasopressors has traditionally been restricted due to concern over a perceived potential threat to flap survival. Overall, these factors make the control of blood pressure and fluid balance difficult. As a result, sedation is frequently reduced either by nursing staff or doctors to mitigate hypotension. However, reducing sedation in turn causes difficulties with maintaining the head in a strictly neutral position. This is further exacerbated by a high incidence of delirium in this group of patients, with a significant smoking and alcohol intake history.
Another issue that arose was the need for a clear plan for escalation. Relative unfamiliarity with caring for maxillofacial patients – on the part of both junior trainees and nursing staff – made it hard to judge the appropriate triggers for seeking advice from the surgeons and seniors. This is particularly pertinent in the out-of-hours period when support is remote.
Once various problems were identified, a search for evidence on current best practice was conducted. A literature review was carried out on existing guidance on the postoperative care of maxillofacial oncology patients, as well as for evidence on the effect of vasopressors on free tissue flap survival. Intensivists at other large centres with maxillofacial oncology work were consulted to enquire about their management of this group of patients and to compare the types of problem encountered.

Intensivists vs maxillofacial surgeons
Through undertaking this project, it became apparent that one of the key challenges arose from differences in priorities between maxillofacial surgeons and intensivists.
Maxillofacial surgeons wish to maximise the chances of successful tissue transfer by keeping the patient’s head neutral through sedation, while maintaining a reasonable mean arterial pressure and avoiding flap oedema to ensure adequate blood flow to the tissue flap. Intensivists wish to optimise the fluid status as guided by clinical signs, evidence of end organ perfusion – such as urine output – and acid–base balance, including lactate and base excess. Once fluid status has been optimised, blood pressure should ideally be supported with the use of a vasopressor to achieve a target mean arterial pressure tailored to the individual patient.

Implementation
This project started by gaining a clear understanding of the common problems encountered when caring for maxillofacial oncology patients in the postoperative period through speaking to different groups of healthcare professionals involved. Involvement of all parties throughout the process provided opportunities for input and for concerns to be voiced at every stage during the development of the guidelines, and promoted shared ownership of the finished product.
A literature review was instrumental in demonstrating that there is no conclusive evidence at present to demonstrate that use of vasopressors threatens free tissue flap survival. There is some evidence to suggest that low-dose noradrenaline increases free flap skin blood flow [2].
Enquiry into the best practice at other centres with maxillofacial oncology patients showed that fluid balance is achieved with cardiac output monitoring, judicious fluid resuscitation – as guided by clinical picture and cardiac output indices – and routine use of low-dose noradrenaline to achieve a target mean arterial pressure.
A draft of the guidelines was developed which aimed to address issues elicited in the research stage. This was circulated among all the parties involved in the consultation process for comments. A designated period of time of two weeks was allowed for responses to be received and the guidelines were edited according to the feedback received.
A face-to-face meeting between intensivists and surgeons provided an opportunity to present the gathered evidence and was helpful in finalising the guidelines through allowing a consensus to be reached. Once a final version of the guidelines had been agreed upon, it was widely disseminated to all doctors and nursing staff on the intensive care unit. The guidelines were made easily available in laminated form in the patient admission pack, and accessible by the individual bedside.
The resulting guidelines are written for junior trainees; they are concise and simple to follow. The guidelines provide step-wise guidance on managing the patient in an A to E format, mirroring the A to E clinical assessment of the patient. They allow for sedation to be maintained, hypotension to be counteracted by careful fluid challenges of 250ml of Hartmann’s solution up to a limit of one litre as indicated by clinical findings and acid–base balance, and use of low-dose noradrenaline after fluid optimisation. The guidelines also set clear triggers for escalation and empower juniors to seek advice whenever they are concerned. Finally, there is guidance on issues specific to this group of patients. including care of drains and donor wound sites, as well as a proactive management of delirium.
An audit will be conducted in due course to ascertain the usefulness of the guidelines and to refine the guidance as indicated.

References
1. Seema, A.M., Senthilnathan, P. & Narayanan, V. (2010) Management of post-operative Maxillofacial oncology patients without the routine use of an intensive care unit. Maxillofac. Oral Surg. 9(4), 329–333
2. Eley, K.A., Young, J.D. & Watt-Smith, S.R. (2012) Epinephrine, norepinephrine, dobutamine, and dopexamine effects on free flap skin blood flow. Plast Reconstr Surg. 130(3), 564–570

Authors
Sindy Lee is a CT1, Anaesthetics, at William Harvey Hospital.
Ranjit Dulai is an intensive care and anaesthetic consultant at William Harvey Hospital

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