Ethics, preoperative considerations, anaesthesia and analgesia

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5 Ethics, preoperative considerations, anaesthesia and analgesia

This chapter encompasses the wide ranging area of perioperative care, from ethical issues surrounding consent, to preoperative preparation and optimization, as well as strategies for the management of postoperative pain. An overview of anaesthesia is included with particular emphasis on its impact on preoperative preparation and selection of patients for surgical intervention.

Ethical and legal principles for surgical patients

The level of trust invested in surgeons by patients when they submit to a surgical procedure is unique in society, as is the potential for harm and exploitation. It is paramount therefore that the practice of surgery is subject to ethical and legal principles that enshrine the rights of patients and the duties of surgeons within the context of varying societal expectations. Medical ethics is a complex area, particularly with the challenges that advances in bioethics and new technologies bring, and there should be sufficient latitude within the framework of medical ethics to accommodate differing views in resolving ethical dilemmas. In the United Kingdom, ethical standards are upheld by regulatory bodies such as the General Medical Council and the Surgical Royal Colleges (Table 5.1).

Table 5.1 The duties of a doctor registered with the General Medical Council

Patients must be able to trust doctors with their lives and health. To justify that trust you must show respect for human life and you must:
Make the care of your patient your first concern  
Protect and promote the health of patients and the public  
Provide a good standard of practice and care Keep your professional knowledge and skills up-to-date
  Recognize and work within the limits of your competence
  Work with colleagues in the ways that best serve patients’ interests
Treat patients as individuals and respect their dignity Treat patients politely and considerately
  Respect patients’ right to confidentiality
Work in partnership with patients Listen to patients and respond to their concerns and preferences
  Give patients the information they want or need in a way they can understand
  Respect patients’ right to reach decisions with you about their treatment and care
  Support patients in caring for themselves to improve and maintain their health
Be honest and open and act with integrity Act without delay if you have good reason to believe that you or a colleague may be putting patients at risk
  Never discriminate unfairly against patients or colleagues
  Never abuse your patients’ trust in you or the public’s trust in the profession
You are personally accountable for your professional practice and must always be prepared to justify your decisions and actions.

Medical ethics is not just an abstract subject but a practical and rigorous discipline that applies on a daily basis to surgical practice. Its importance cannot be overestimated. This section seeks to give an overview of medical ethical and legal principles with the exception of the ethics surrounding transplantation which is discussed in the chapter on transplantation.

Principles in surgical ethics

Surgeons regularly need to make decisions that involve a broad understanding of medical ethics. Obtaining fully informed consent is probably the most common example, but surgeons are often involved in ethical dilemmas in acute situations involving unconscious and critically injured patients. Ethical issues are also encountered in surgical research and in the world of surgical publication. The information below cannot cover every prevailing philosophy relating to medical ethics, but is intended to provide guidance that can be applied to most situations that the surgeon is likely to encounter.

Principalism

Principalism is a widely adopted approach to medical ethics. Championed by Beauchamp and Childress, it judges all possible actions in a particular ethical dilemma against four principles. These are autonomy, beneficence, non-malfeasance and justice (Summary Box 5.1). Each is considered in more detail below and while addressed separately, it becomes apparent that the principles are linked and do not simply cover four unrelated issues. Protagonists of this approach to bioethics suggest that it provides a practical framework for working through ethical dilemmas, allowing identification of important issues and is universally applicable with its four principles widely acceptable irrespective of culture or religious beliefs. The principles can be applied to most surgical clinical scenarios and if each element is given due consideration it is unlikely that the resulting decision will be unethical.

Informed consent

General considerations

Informed consent is central to the practice of surgery, and has to be obtained for surgical procedures, other treatment modalities, investigations, screening tests and prior to patient participation in research. Informed consent is not only ethically correct but also a legal riht and should be respected even if the patient’s wishes are at variance with the surgeon’s opinion. Informed consent can only be obtained from patients with ‘capacity’. This should be assumed for all conscious adults unless there is evidence to the contrary. The patient’s views must be respected and upheld after an information sharing process that conveys all the information the patient needs and wants in order to make a decision. The surgeon must maximize the opportunity for patients to consent and facilitate the process wherever possible.

Capacity exists if a patient can:

Circumstances where the capacity to consent may not exist:

Other important considerations in obtaining consent relate to who should obtain consent and when, and what information should be shared/withheld and in what format. In general terms, the surgeon performing the procedure has responsibility to obtain consent but this can be delegated provided the person to whom it is delegated:

The information that should be shared with a patient to obtain consent should start from a mutual understanding by both doctor and patient of the medical condition, as well as the patient’s views, beliefs and prior knowledge. All treatment options should be detailed, including the option of no treatment alongside the risks, side effects, potential benefits and burdens and the risk that the treatment will be unsuccessful. All potential serious adverse outcomes, no matter how rare should be discussed, along with more frequent minor complications. Risks and benefits should, wherever possible be quantified in percentage terms. These figures should derive from audited local/personal practice and not simply plucked from the literature. It is acceptable for the surgeon to give the patient advice; but, in such circumstance, any conflict of interest must be declared.

If a patient expresses the wish that they do not want the information required for informed consent and understands the potential consequences, then information can be withheld on the basis of non-malfeasance, but only when serious psychological harm might ensue and not simply because the patient may be upset or refuse treatment. This is called ‘therapeutic privilege’. The provision of procedure specific patient information sheets can supplement the process of informed consent, but does not negate the doctor’s responsibility to ensure patient’s understanding of the procedure.

Consent may be implied or explicit. Implied consent is considered adequate for routine interventions with negligible risks where patient consent is implied by their cooperation (e.g. venepuncture). The majority of interventions require explicit consent; this may be oral or written. It is perhaps surprising that although written consent is obtained for the majority of procedures, it is only a legal requirement for organ donation and fertility treatment in the UK. Nevertheless, the existence of a written, dated form of consent provides evidence that a consultation covering specific issues was likely to have taken place.

Increasingly in the UK patients may not have sufficient English to enable the process of informed consent. In such circumstances it is tempting to conduct the consultation and consent process via a family member or friend acting as an informal interpreter. However, best practice is to use the services of an official translator. Similarly, written information should in the appropriate language; if this is not possible the translator should read it out to the patient who then has an opportunity to ask questions back through the translator. It goes without saying that the medical records should clearly document that this process has taken place.

Consent in specific circumstances

Confidentiality

Confidentiality is a central element in the doctor–patient relationship. There are exceptions where confidentiality can and should be breached for the protection of others (e.g. notifiable diseases such as tuberculosis). In the context of multidisciplinary team working, only information necessary to enable treatment by a third party should be divulged. When patients are discussed for the purposes of teaching or publication, patient identity must be concealed. Confidentiality is not just an important principle, it may be legally enforceable, for example by the Data Protection Act.

See Table 5.2 for important sources of information regarding ethics in medicine.

Table 5.2 Sources of further information on ethics

Publications

Websites

Specific topics

Negligence

In order for a surgeon to be found negligent three pre-requisites must be fulfilled. Firstly, it must be demonstrated that the surgeon owed the patient a duty of care (this is usually assumed), secondly, it must be shown that that the doctor breached that duty of care; and, thirdly that, on the balance of probabilities (more likely than not), the breach of duty resulted directly in harm (causation). Medical negligence can relate to diagnosis, treatment and the failure to warn a patient of risks that would have resulted in the patient refusing an intervention. The standard against which a doctor’s performance is measured was established in case law in 1957 (the Bolam case). This states that a doctor is not guilty of negligence if he has acted ‘in accordance with a practice accepted as proper by a responsible body of medical men skilled in that particular area’. In practice, Bolam defends a doctor’s practice if a body of medical opinion can be found to support that doctor’s actions. It facilitates the defence of minimal acceptable practice rather than ideal practice. A subsequent House of Lords ruling went further stating that, ‘the court has to be satisfied that the exponents of the body of opinion relied on can demonstrate that such an opinion has a logical basis … that the experts have directed their minds to the question of risks and benefits and have reached a defensible conclusion’. This updated ruling (Bolitho) provides the legal basis for most complaints that result in an allegation of negligence. Several professional organizations in the UK offer advice and support to doctors including the British Medical Association, the General Medical Council, and medical defence organizations.

Completion of a death certificate

Following the death of a patient, it is a legal requirement that a death certificate be completed before the body is released for cremation or burial. Death certification must be completed by the doctor who has attended the deceased during their last illness and includes a record of the patient’s name and age, as well as the date, time and place of death. The cause of death has to be recorded, as well as any contributing conditions that have led directly to the cause of death and significant conditions that contributed to the death but are unrelated to the disease causing it. In certain situations a death has to be referred as a legal requirement to the coroner’s office in England, Wales and Northern Ireland or to the Procurator Fiscal in Scotland for consideration of a post mortem examination to establish the cause of death. These include: recent surgery, where death may be due to abortion, accidental death, death in suspicious/violent/unnatural circumstances, death due to suspected poisoning, self neglect, negligence or suicide, death occurring in prison or police custody, where the death may be due to industrial disease or related to the deceased person’s employment, where the cause of death is unknown; and unexpected death.

Where cremation is requested, a separate cremation form has to be completed by a doctor who attended the deceased during their last illness and a second doctor who is at least five years full registration. Care must be taken to identify the presence of pacemakers and other potential explosive devices in the body. The cremation of foetal remains of less than 24 weeks gestation does not require a cremation certificate.

Ethics committees

Research on human subjects is necessary to advance medical knowledge and treatment. Ensuring that it is carried out in a safe and ethical way is the remit of the ethics committee. The Declaration of Helsinki sets out the principles of ethical research. All clinical trials involving human subjects or tissue must receive ethical approval prior to commencing recruitment. For information on how ethical approval is obtained in the UK see the National Research Ethics Service which is part of the National Patient Safety Agency (http://www.nres.npsa.nhs.uk/). The composition of ethics committees is important and should reflect societal diversity in terms of age, gender, ethnicity and disability and embody a broad range of experience and expertise so that the scientific, clinical and methodological aspects of a research proposal can be reconciled with the welfare of the research participants.

Ethics committees take into consideration a whole range of aspects of a research proposal before giving approval. Their primary consideration is to safeguard the rights, safety and wellbeing of research subjects. They examine the recruitment process, including informed consent, the quality of information given to subjects, payments to subjects, the risks of the research protocol including safety measures and information, compensation procedures and indemnity. The likelihood and capability of the trial design to answer the research questions is considered as well as adequacy of resources, plans for data processing, storage and protection.

Preoperative assessment

Careful preoperative assessment is fundamental to achieving good surgical outcomes. The same principles apply to both emergency and elective situations, the only difference usually being the extent to which preoperative assessment must be compromised when an emergency condition requires urgent intervention.

Assessment of operative fitness and perioperative risk

In the elective surgical setting, preoperative assessment takes place in several stages beginning at the point of referral. A good referral letter should include details not only of the presenting complaint but also of the patient’s general health, co-morbidities and current medication. The first contact with the surgical team is usually in the out-patient clinic and this consultation may lead to a decision to offer surgery. In reaching such a decision, the surgeon should consider not only the physical fitness of the patient to withstand the proposed surgery, but also the likely impact on their social and emotional wellbeing. When making the decision to operate, the risks and potential benefits of surgery should be weighed against those of alternative or no treatment. The purpose of preoperative assessment is to prepare the patient for surgery, identify co-morbid conditions, estimate and perioperative risk by optimizing the patient’s physical condition. The majority of preoperative assessment for elective surgery takes place in the preoperative assessment clinic one to two weeks before surgery, and culminates in the admission immediately prior to, increasingly in the UK on the morning of, surgery.

The first priority is to establish the severity and extent of the condition requiring surgery by employing appropriate imaging and other investigations. For example, it is important to know that both recurrent laryngeal nerves are functional prior to thyroid surgery as damage is a recognized complication of this type of operation, on the other hand malignant conditions require appropriate staging to establish the disease extent. The second objective is to identify co-morbid conditions through careful clinical assessment and through optimization, minimize perioperative risk. Figure 5.1 details the areas of potential perioperative risk and Figure 5.2 shows a logical sequence of preoperative assessment. Details of previous operations and anaesthetics should be sought, as well as drug, alcohol and smoking history, specific allergies and concerns. Investigations to assess the surgical condition, co-morbid conditions and general health should be arranged as soon as possible to minimize surgical delay. Thorough and timely preoperative assessment is essential to avoid the expense and delay of cancelled or delayed surgery. Good quality assessment and appropriate optimizations prior to admission mean that many patients can be admitted on the day of surgery.

An anaesthetic review should be requested prior to admission where there is increased risk, fitness for surgery is in doubt or there are specific anaesthetic issues requiring input. Other specialist input may be required, including cardiology, respiratory and haematology.

On the morning of surgery, both the surgeon and anaesthetist should reassess the patient and identify outstanding issues and any changes in their condition. Care should be taken to ensure that all investigation results are available as well as necessary blood products and special equipment. Details of the anaesthetic should be discussed, and postoperative analgesic strategies, taking into account patient preferences wherever possible.

In the emergency situation this process is condensed. Judging the timing of surgery is crucial. The surgeon must determine which interventions will optimize the patient’s condition while avoiding deterioration due to unnecessary delay progression of the acute surgical problem.

Oxygen delivery in minimizing operative risk

A number of important studies have demonstrated that postoperative morbidity and mortality are related to inadequate oxygen delivery to the tissues, resulting in hypoxia. Oxygen delivery (DO2) is dependent on cardiac output (CO) and the oxygen content of arterial blood (CaO2).

image

The arterial oxygen content in turn depends on the delivery of oxygen to the alveoli, its efficient transfer from alveoli into blood, adequately functioning haemoglobin, the arterial partial pressure of oxygen and arterial haemoglobin oxygen saturation. In an average resting adult an oxygen requirement of approximately 250 ml/min is exceeded by delivery of around 1000 ml/min, resulting in considerable reserve. When oxygen demand increases, cardiac output may rise and tissue oxygen extraction may increase to up to 50–60% in order to compensate. If this does not meet tissue oxygen demand, hypoxia with anaerobic metabolism ensues. If uncorrected this can cause local and remote organ damage, dysfunction, multiple organ failure and ultimately death. It has been shown that the duration of oxygen debt correlates with the presence and magnitude of postoperative complications and mortality. It therefore follows that patients with poor cardiovascular and respiratory reserve or anaemia, and who are less able to increase oxygen delivery, are at higher perioperative risk and that measures taken to optimize their condition and oxygen delivery will help to minimize that risk.

Goal directed measures to optimize cardiac index, oxygen delivery, mixed venous oxygen saturation and minimize anaerobic metabolism using intraoesophageal Doppler probes, pulmonary artery catheters, intravenous fluid loading, blood transfusion, supplemental oxygen and inotropes have all been shown to improve outcomes.

Systematic preoperative assessment

Smoking

All patients should be offered support to quit smoking, particularly once the decision to operate has been made. The benefits of preoperative smoking cessation are listed in Table 5.3 and should be explained to the patient. Some of the benefits occur within hours (reduced circulating nicotine and carboxyhaemoglobin) while others take weeks, months, or even years. Despite the significant advantages in the perioperative period, many patients are unable or unwilling to stop smoking prior to and after their surgery. Referral to specialist services that support patients to stop smoking may help.

Table 5.3 Benefits of preoperative smoking cessation

Surgical

Other

Drug therapy

A comprehensive drug history should be recorded prior to admission for surgery. In general patients should take their routine medication right up to the time of surgery. The perioperative management of diabetes mellitus and patients on anticoagulation is considered separately. Drugs that require special consideration in the perioperative period are discussed below.

Allergies

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