October 29, 2004
Principles of Post-Operative Patient Care
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SummarySurgery causes physiological stress on the body and carries inherent risks such as shock and haemorrhage. This article discusses cardiogenic and hypovolaemic shock and outlines the principles of safe and effective post-operative care, including recognising hypovolaemia, maintaining fluid balance and administering pain control.
* Pain relief
* Post-operative care
* Surgical nursing
These key words are based on subject headings from the British Nursing Index. This article has been subject to double-blind review.
Aim and intended learning outcomes
Although different surgical procedures require specific and specialist nursing care, the principles of post-operative care remain the same. This article aims to explore the principles of caring for post-operative patients by reviewing the literature and scrutinising the available evidence for surgical nurses to reflect on and use to enhance the care they provide.
After reading this article you should be able to:
* Discuss the observations that are essential for; maintaining haemodynamic stability and determining shock in post-operative patients.
* Identify the importance of monitoring and maintaining fluid balance.
* Identify the reasons for oxygen therapy in the post-operative patient, the methods of administration and potential problems with pulse oximetry measurement.
* Briefly outline the physiological mechanism for pain perception, the options for post-operative pain management and methods available for determining the severity of pain.
* Outline the complications that can occur as a result of surgery and the strategies that can be employed to prevent them.
In 2001 the National Confidential Enquiry into Patient Outcome and Death (NCEPOD) published an audit of post-operative deaths. It showed how audit can be used to aid the learning process because it highlighted many consistent challenges to good patient care. Many of the audits of patient deaths undertaken by NCEPOD highlight issues of fluid balance and cardiogenic or hypovolaemic shock (NCEPOD 2001). It is for this reason that this article focuses on cardiogenic and true hypovolaemic shock.
Although patients with shock can be described as having circulatory failure, there are two other classifications of shock that can affect surgical patients (Anderson 2003). These are obstructive shock (including pulmonary embolus, cardiac tamponade and tension pneumothorax) and apparent hypovolaemia (including sepsis, anaphylaxis, neurogenic and adrenal insufficiency) (Anderson 2003). Although these other two classifications of shock are just as important as cardiogenic and true hypovolaemic shock, because this article aims to be an educational resource for the general surgical audience related to the NCEPOD (2001) findings, these have not been included. However, Anderson (2003), Collins (2000) and Edwards (2001) are good educational resources regarding obstructive and apparent hypovolaemic shock.
There are several other essential elements to providing safe nursing care for post-operative patients, such as the administration of oxygen, pain control and preventing complications. It is vital that nurses working in the surgical specialties are aware of the evidence available to ensure safety of care for patients.
While these elements are fundamental to post-operative care, good surgical care starts at admission with the provision of pre- operative education to reduce patient anxiety as well as the inherent physical risks of surgery (Hughes 2002, Torrance and Serginson 2000). Pre-operative education should be reinforced post- operatively because patients forget up to 60 per cent of the information they are given as a result of anxiety (Bysshe 1988).
Effects of surgery
Surgery causes physiological stress (Torrance and Serginson 2000). During times of stress, the hypothalamic-pituitary-adrenal pathway is activated. This causes a release of catecholamines, such as adrenaline (epinephrine) and noradrenaline (norepinephrine), via the sympathetic-adrenal medullary system.
Emotional distress has also been found to increase the production of cortisol, a steroid hormone produced in the cortex of the adrenal gland. Cortisol has several functions in the body that can have implications for the post-operative patient, such as:
* Increasing metabolism.
* The excretion of water through mineralocorticoid activity.
* Increasing cardiovascular tone in the presence of vasoactive hormones, such as angiotensin II, vasopressin and adrenaline (epinephrine).
* Increasing temperature and blood glucose levels, as well as reducing the immune response, which in turn diminishes inflammation enabling wound healing.
An increase in cortisol can also lead to muscle or protein depletion, which can delay wound healing. For this reason nutrition plays an important role in post-operative care (Clancy and McVicar 2002) and pre- and post-operative fasting times need to be considered. However, it has been found by O'Callaghan (2002) that nurses fast patients for longer than necessary. Bisgaard and Kehlet (2002) suggest that patients can be fed orally, even in the early stages following major abdominal surgery, without increased risk of paralytic ileus or dehiscence of the gut anastomosis. Clancy and McVicar (2002) discuss the effects that surgery can have on protein depletion and for this reason the increased risk of malnutrition following surgery can have a notable effect on wound healing.
Elevated levels of cortisol and catecholamines can have direct implications for surgical patients with specific conditions, such as myocardial ischaemia and hypertension because the increase in cortisol affects cardiovascular tone. Patients with diabetes can have problems controlling their blood glucose levels for more than a week after an operation due to hyper-reactivity states and insulin resistance caused by the exaggerated response of glucogenesis to the production of cortisol (Halpin 1988, Steptoe 1991).
Monitoring haemodynamic stability
Because of the body's physiological response to stress and the inherent surgical risk of shock and haemorrhage, regular post- operative observations are the cornerstone of safe surgical practice. The nature of the operation as well as the method of pain control will determine the regularity of these observations.
Indicators of haemodynamic stability should be observed in all surgical patients. These should include:
* Blood pressure.
* Peripheral oxygen saturation.
* Respiration rate.
Because of the risk of failure of electronic equipment for measuring observations it is essential that nurses develop the skill and dexterity to monitor patients' vital signs with traditional manual equipment. The senses, such as hearing and touch, can be employed because reliance on electronic equipment can also prevent the early recognition of arrythmias that can be associated with cardiogenic shock.
Some patients might benefit from central venous pressure (CVP) monitoring in the ward environment to determine circulatory volume (Woodrow 2002). Drain output can be an unreliable method of determining blood loss because they can become blocked with clots (Anderson 2003). Chest X-rays are a useful tool in determining pulmonary oedema, as are daily weights in assessing fluid balance (Toto 1998).
A reduction in systolic blood pressure following surgery can indicate hypovolaemic shock which can lead to inadequate tissue perfusion, damage at a cellular level and ultimately major organ failure (Anderson 2003). However, blood pressure measurement can be variable. Because of the body's compensatory mechanisms patients can lose up to 30 per cent of their circulatory volume before the effects of hypovolaemia are reflected in systolic blood pressure measurements or heart rate (Anderson 2003, Collins 2000). Therefore, when assessing patients, it is useful to consider the early signs of reduced tissue perfusion in detecting signs of shock (Anderson 2003, Collins 2000, Jevon and Ewens 2002):
* Restlessness or confusion as a result of cerebral hypoperfusion or hypoxia.
* Increased respiratory rate occurs before signs of tachycardia and hypotension.
* Tachycardia as the heart attempts to compensate for the low circulatory blood volume.
* Low urine output of
* Increased temperature but this can also be due to the immune response associated with surgery.
* Cold peripheries resulting in a poor signal on the pulse oximeter.
Whatever the cause of hypovolaemic shock, the aim of treatment is to restore adequate tissue perfusion. Excessive blood loss might require blood transfusion and occasionally surgical intervention, while often fluid resuscitation, with crystalloid or colloid and increased oxygenation to maintain saturation above 95 per cent, is sufficient to promote recovery for many patients, if the signs are recognised in the compensatory phase. The maintenance of a pulse oximeter reading above 95 per cent can be difficult due to the dilution o\f blood with intravenous fluids (Collins 2000).
Cardiogenic shock is another post-operative complication that results in the death of many acutely ill surgical patients (NCEPOD 2001). This is caused by the failure of the myocardial 'pump', which could be a result of a pre-existing condition (Anderson 2003, Jevon and Ewens 2002). In response to surgery the metabolic demands of the body increase and adrenaline (epinephrine) and noradrenaline (norepinephrine) are released as the heart rate increases due to the compensatory mechanism. The body's tissues and cells then require more oxygen which exacerbates the performance of the already pressurised myocardium. This can result in a cardiac arrhythmia or myocardial infarction (Edwards 2001, Jevon and Ewens 2002).
Treating cardiogenic shock depends on the patient's condition. All patients will require close observation with supplementary oxygen to meet the body's metabolic demands. Some patients might require inotropic support while others might require chemical cardioversion with amiodarone or digoxin to treat arrythmias and improve contractility of the heart (Anderson 2003).
Many acute hospital trusts now employ outreach teams, a result of a commitment in Comprehensive Critical Care (DoH 2000), to provide support for ward-based staff in caring for highly dependent patients outside the ward environment. While there is little evidence in the literature to support the success of these teams in terms of patient outcomes, there is a great deal of anecdotal evidence to advocate their existence in preventing admission to critical care areas and educating ward-based staff (Coombs and Moorse 2002, Robson 2002).
In health, fluid balance is regulated by autoregulatory homeostatic mechanisms. In ill health, or following surgery, where there is a disturbance to homeostasis, the extrinsic - or negative feedback - mechanism of fluid and electrolyte balance attempts to restore homeostasis (Clancy and McVicar 2002). In many surgical patients these extrinsic mechanisms require medical assistance to replace the fluids and electrolytes that are lost during surgery, thus restoring the constant internal environment.
There are two major fluid compartments. Intracellular fluid (ICF) is contained in the cell membrane while the extracellular fluid (ECF) is found outside the cells. The ECF is divided further into two parts which are the intravascular volume and interstitial fluid that surrounds the cells (Clancy and McVicar 2002, Heitz and Home 2001, Sadler2001).
Water and its solutes are able to shift between the compartments through selectively permeable membranes that only allow molecules of a certain size to pass. Transport of body fluid across these membranes occurs through either diffusion, active transport, filtration, facilitated diffusion, capillary dynamics or osmosis (Clancy and McVicar 2002, Heitz and Home 2001).
There is a potential 'third' space in the gut into which fluid can shift and accumulate. This fluid shift can also occur at the site of surgery resulting in oedema due to the inflammatory response which is initiated during surgery (Carroll 2000, Clancy and McVicar 2002, Heitz and Home 2001). The fluid here is temporarily unavailable and replacement fluids are essential to prevent hypovolaemic shock.
Fluid shifting from one compartment to another has direct effects on urine output as the circulatory volume decreases. For these patients the use of diuretics to stimulate urine output can be dangerous because the fluid is removed from the extracellular volume, causing further hypovolaemia and can lead to circulatory collapse (Heitz and Home 2001, Sadler 2001).
Anderson (2003) suggests several iatrogenic factors that can contribute to fluid imbalance in the post-operative period, such as:
* Bowel preparation.
* Infiltrated cannulaes.
* Poor fluid prescription.
* Pre-operative fasting times.
Therefore, the replacement of fluids in the post-operative period is essential to ensure adequate hydration and safe nursing practice.
Fluid replacement regimens depend on the type and volume of fluids lost during surgery. The most commonly used fluids on the surgical ward are crystalloids and colloids, which have different functions. Crystalloid fluids include (Clancy and McVicar 2002, Sadler 2001):
* 0.9% sodium chloride. This is used to support the ECF level. Saline is an isotonic solution and exerts the same osmotic pressure as that of the cells. Because its osmolarity is similar to that of the body's fluid it does not move into the intracellular space in large quantities.
* 5% dextrose. This is an isotonic solution used to support the intracellular space. However, as the glucose is metabolised by the cells it becomes hypotonie, allowing the fluid to shift across the membrane into the intracellular space.
* Hartmann's solution (Ringer's lactate solution) provides greater support for the extracellular space as it closely mimics the body's ECF.
Colloid infusions act as plasma expanders and the purpose of these infusions is to support the extracellular compartment. Because of the size of the protein molecules in the fluid they are unable to shift across the capillary membrane and their high osmotic pull encourages a shift of fluid from the intracellular to the extracellular space increasing the intravascular volume (Heitz and Home 2001, Sadler 2001).
The aim of fluid management in surgical patients is to support the maintenance of fluid levels in both the intracellular and extracellular spaces to maintain homeostasis. Crystalloids, in a standard fluid replacement regimen, are often given at a ratio of two litres of 5% dextrose to one litre of 0.9% saline in a 24-hour period to support the body's cellular requirements (Hope et al 1998, Torrance and Serginson 2000). However, in a fluid replacement regimen for patients undergoing major surgery the prescription of intravenous fluids will take into account factors such as the patient's weight, fluid and electrolyte excess or deficit, insensible water loss and losses from the gastrointestinal and renal tract (Anderson 2003).
Oxygen is given initially to post-operative patients on reversal of anaesthesia to encourage the transport of anaesthetic gases across the alveolar/capillary membrane in the lungs and out of the body. Supplemental oxygen is often required in higher concentrations because of the increase in the metabolic rate caused by surgery, since it results in physiological stress and trauma (Torrance and Serginson 2000).
Following surgery, the increased production of cortisol and sympathetic nerve activation, as well as the metabolism of glucose, fatty and amino acids, reduce the secretion of insulin. This in turn increases the metabolic rate which has implications at a cellular level as the Krebs citric acid cycle increases the demand for oxygen supply (Clancy and McVicar 2002).
In the post-operative period, if the patient is unable to meet the body's demand for increased oxygenation, respiratory failure can occur. This can be measured in arterial blood gas sampling as a decrease in blood pH and partial pressure of oxygen levels and a rise in partial pressure of carbon dioxide levels.
In some intensive care areas non-invasive techniques of monitoring carbon dioxide levels such as end-tidal carbon dioxide monitoring (capnometry), which measures the volume of carbon dioxide in exhaled air as it leaves the ventilated patient, are being used as a cost-effective method of measuring the partial pressure of carbon dioxide in arterial blood (Capovilla et al 2000).
Monitoring oxygen saturation has become a routine procedure on surgical wards, with the use of pulse oximetry providing an accurate estimation of the oxygenation of arterial blood (Howell 2002).
The term 'saturation' refers to haemoglobin that has four binding sites to which the oxygen molecules can attach, creating oxyhaemoglobin which the pulse oximeter measures (Clancy and McVicar 2002). It is these cells that are responsible for 97 per cent of oxygen transport in the body, while the remaining 3 per cent are dissolved in plasma (Pruitt and Jacobs 2003). However, pulse oximeter readings should be used in conjunction with the clinical assessment of respiration, including rate, rhythm and depth and the use of the accessory respiratory muscles (Casey 2001).
Although the use of such equipment is commonplace, factors that can contribute to poor signals from the pulse oximeter and potentially inaccurate readings that could affect the management of the surgical patient should be considered. These include reduced tissue perfusion or poor peripheral circulation resulting in a poor signal for analysis, hypothermia (shivering) causing an alteration in the light pathway, and strong light that can affect the photo detector in the probe and cause low readings (Anderson et al 2002). Conditions such as hypovolaemia and underlying pulmonary or cardiac disease can affect oxygen transport and thus reduce oxygen saturation (Casey 2001).
Giving oxygen in a surgical environment usually involves delivery through a face mask with a flow regulator. However, some patients will require oxygen therapy for longer periods, which should be given via a humidifier to prevent mucous membranes and pulmonary secretions from becoming dry and uncomfortable for the patient (Field 2000).
Dry secretions can lead to difficulty in expectorating post- operatively and in oxygen transport, particularly if patients have undergone abdominal surgery and their pain is poorly controlled, because this causes difficulty in inspiration. In instances such as these, atelectasis can occur which not only affects oxygen transportation as the alveoli become blocked with plugs of mucus and collapse, but can also lead to chest infection and pneumonia (Beers 2003). Early referral for chest physiotherapy can reduce the incidence of these problems.
Depending on the severity of \the disease and the condition of the patient, treatment to loosen secretions and improve oxygen transport can be given in the following ways (Beers 2003, Woodrow 2003a, 2003b):
* Deep breathing and coughing exercises, except in specific surgery of the ear, eye, brain or abdominal hernias because pressure can be increased at the site of the operation.
* Chest physiotherapy for percussion and providing education for patients.
* Continuous positive airway pressure (CPAP) or biphasic positive airway pressure (BiPAP), ensuring positive end expiratory pressure, which recruits the surface area of the alveoli so gaseous exchange can occur.
* Mechanical ventilation in severe cases. While pre-operative education can reduce the risk of atelectasis occurring, patients should be assessed individually, because not all will be required to undertake deep breathing exercises. Those who would benefit should carry out the exercises five to ten times per hour with the inspiratory breath being held for at least three seconds (Field 2000). For many post-operative patients this will require nursing supervision and support to empower patients in their care to make informed choices about undertaking deep breathing exercises.
Although humidification systems and simple face masks are the usual methods of delivering oxygen to post-operative patients in the UK, a study by Bolton and Russell (2001) suggests that nasal spectacles can be as efficient in certain cases. The exceptions were patients who 'mouth breathe' and those who underwent lower abdominal surgery who were found to desaturate, making the device less effective in delivering oxygen.
In the majority of surgical patients the concentration of oxygen delivered via devices is given at a rate to maintain an oxygen saturation level above 95 per cent and prevent hypoxia (Anderson 2003). For some patients with respiratory dysfunction, such as chronic obstructive pulmonary disease (COPD), oxygen needs to be delivered carefully at a rate of 24 to 28 per cent because of the altered respiratory drive (Field 2000, Pruitt and Jacobs 2003). In patients with COPD, the body becomes accustomed to a higher carbon dioxide concentration in the blood. Giving high concentrations of oxygen will alter cell physiology and the body will interpret this as a hypocapnoeic event. To reduce the levels of hypoxaemia, but allow raised carbon dioxide levels, a lower concentration of oxygen is required (Clancy and McVicar 2002). While supplementary oxygen therapy is an important element of post-operative surgical care, oxygen is a drug and can be dangerous to some patients, especially those with respiratory dysfunction, and for this reason it should be prescribed by medical staff (BNF 2003a, NMC 2002).
Pain following surgery is inevitable for many patients, but because gender, age, psychological and cultural factors determine the response to pain, each patient's coping mechanism will be different (Kitcatt 2003).
Pain is determined in the brain by the central nervous system through nerve transmission. This also occurs following surgery when the inflammatory response is initiated because of damage to the tissues. The A delta fibres and C fibres of the nervous system are stimulated by prostaglandin which is released from the damaged tissues (Clancy and McVicar 2002). These mediators then bind with receptors called nociceptors at the site of injury. The transmission of the impulse along the nerve fibres occurs with the presence of chemicals to the dorsal horn of the spinal cord where the pain message is then modulated. The pain message is modified by the presence of peptides such as substance P, bradykinin and prostaglandin E. These peptides act as inflammatory mediators and initiate the inflammatory response. These neurotransmitters then send the pain message to the brain, where perception occurs (Rawal 1998, Thomas 1998).
In the surgical patient, the A beta fibres also play a part in the localised perception of pain. The A beta fibres are usually associated with the perception of touch, pressure and vibration. Following surgery these fibres are also stimulated by tissue inflammation, making wounds painful to touch. This is known as touch allodyna, or secondary hyperalgesia, which leads to profound pain on movement or at dressing change (Ekblom and Rydh-Rinder 1998).
Severe pain causes several physiological responses that can be detrimental to the surgical patient. Acute severe pain causes tachycardia and hypertension. It can be dangerous to patients with cardiac dysfunction, especially if there is an element of hypovolaemia, because oxygen demands also increase with acute pain. Respiratory function can also be compromised because patients find it extremely difficult to take deep breaths and use their accessory muscles or the top lobe of the lung to breathe, leading to atelectasis or pneumonia (Anderson 2003, Kitcatt 2003, Nendick 2000, Rawal 1998, Thomas 1998).
Therefore, good pain management can help reduce post-operative complications such as deep vein thrombosis (DVT) and atelectasis, as well as ensure patients are not psychologically affected by their perception of pain.
Depending on the type of surgery the patient is having, there are four pain management options available (Anderson 2003). These are:
* Oral medication.
* Epidural analgesia.
* Intramuscular injection.
* Patient controlled analgesia (PCA).
This follows the guidelines set out by the World Federation of Societies of Anaesthesiologists in relation to the analgesic ladder (Figure 1) (Charlton 1997).
The analgesia used for post-operative pain has advantages and disadvantages for patients. However, the increased use of adjuvant therapy is improving pain control for patients (Table 1).
So what is the best method of pain relief for major surgery - intramuscular analgesia, epidural or PCA? The peaks and troughs associated with 'as required' prescriptions have previously been discussed and, as suggested by Young (2000), can provide an insufficient level of analgesia because the patient generally has to experience pain before he or she receives medication.
Figure 1. World Federation of Societies of Anaesthesiologists ladder
There have been several studies comparing PCA and epidural analgesia following major surgery and, while it has been reported that respiratory depression is reduced in the PCA group because patients control their own dosage, recent studies have produced different results. A small-scale study by Kampe et al (2001) found that patients using the PCA device experienced significantly more side effects from the analgesia than the epidural group. A recent study by Flisberg et al (2003), who evaluated the safety of the method of pain relief as well as its efficiency, found that patients who experienced epidural analgesia reported superior pain relief than the PCA group. There were also fewer episodes of opioidrelated side effects and less occurrences of respiratory depression in the epidural group. Therefore, it could be suggested that epidural analgesia is not only more effective in controlling pain but also carries less risk.
Pain rating scales can range from numerical scoring to visual analogue scales (Bird 2003, Kitcatt 2003). The purpose of these scoring systems is to determine the intensity of pain so that appropriate analgesia can be administered. While the rating scales are widely used, Klopfenstein et al (2000) reported that doctors and nurses underestimate patients' pain and suggested that further education should be provided on the use of pain assessment scales because they are open to interpretation.
Complications of surgery
Two of the most common complications of surgery are chest infection and shock, both of which have been discussed. However, there are also several associated risks following surgery, for example, pulmonary embolus (PE) and DVT.
Table 1. Advantages and disadvantages of analgesia used in post- operative care
Simple nursing interventions, such as early mobilisation and encouraging patients to do leg exercises while in bed, can help to reduce the risk of thrombus formation as well as urinary tract infections, pressure ulcers and constipation (Torrance and Serginson 2000).
Patients undergoing surgery are at greater risk of clot formation because of the nature of surgery and the body's clotting mechanisms. It has been found that 20 per cent of untreated postoperative patients will develop a venous or pulmonary thrombus (Trounce and Gould 2000). Many patients undergoing surgery will be treated with anticoagulants to prevent this complication occurring (Trounce and Gould 2000). Prophylactic treatment can be given with methods such as low-molecular weight heparin (LMWH), subcutaneous heparin injections or a continuous heparin infusion if the patient was anticoagulated previously.
The actions of these two anticoagulants are different. With unfractionated or standard heparin the anticoagulant effect begins within minutes of administration of an intravenous bolus but lasts for only a short time after an infusion has stopped (BNF 2004b). For prophylaxis, the dose is much lower and is administered subcutaneously. With unfractionated heparin only one third of the dose binds to antithrombin and this accounts for the majority of its anticoagulant effect (Hirsh et al 2001). LMWH is made up of fragments of the heparin molecule and the action of the drug is similar to subcutaneous and intravenous heparin, with the exception of the length of time the therapeutic dose lasts often requiring daily administration of the drug (BNF 2004b, Hirsh et al 2001). Subcutaneous LMWH has a half life of up to four hours, twice that of unfractionated heparin (Pharmacia 2004).
Trounce and Gould (2000) describe this method of anticoagulation as being superior to that of low dose heparin. However, studies by Anderson et al (1993) and Hirsh et al (2001) found LMWH to be as effective and safe as unfr\actionated heparin, while one study found there was a significant reduction in mortality from thrombus formation with the use of LMWH (Pezzuoli et al 1989). However, LMWH does have the disadvantage of being more expensive in the UK compared with the US (Bandolier 1995, BNF 2004b). A blanket policy of LMWH for prophylaxis of DVT in all instances may not be cost- effective in the UK but an increase in its use could reduce the cost of the preparation in the long term.
The advantage of subcutaneous thrombus prophylaxis in both methods of anticoagulation is that it does not require activated partial thromboplastin time (APTT) or international normalised ratio (INR) monitoring, while intravenous administration requires regular monitoring of coagulation through frequent blood sampling of APTT and INR (BNF 2004b).
The prescription of anticoagulants to prevent thrombus formation is used in conjunction with the use of anti-thrombus stockings (Anderson 2003). Research by Agu et al (1999) suggests that the use of knee-high stockings - as opposed to full-length stockings - should be adopted in the prevention of DVT. This is because it has been found that incorrectly applied or worn stockings that are folded over at the knee or creased in several places can pose an increased risk of developing DVTs and venous stasis.
The diagnosis of embolus in the surgical patient largely relies on clinical manifestations, such as breathlessness in PE and a hot swollen calf in DVT. The use of D-dimers, which measure the fibrinogen degradation rate and, therefore, the presence of the clotting mechanism, can give a reliable indication of PE or DVT in many instances (Bozic et at 2002, Dempfle 2000). However, because the clotting mechanism is also activated following surgery, it has been suggested that the usefulness of D-dimers up to the 15th day following surgery is limited and cannot provide an accurate diagnosis of DVT or PE (Lippi et al 2001 ). Therefore, investigations such as venograms need to be relied on for diagnosis.
The underpinning principles of safe and effective post-operative care can be made more complicated by the body's physiological response to surgery. However, it is these alterations in physiology that make surgical nursing a demanding but fascinating specialty.
There are elements to caring for patients that can be learned from and improved on (NCEPOD 2001). This article has aimed to explore some of those issues to provide a valuable learning tool for surgical nurses. The exploration of elements such as recognition of hypovolaemia, fluid balance and pain control have been the focus of this article because they are the mainstay of safe and effective practice and can prevent many post-operative complications.
With a good understanding of the concepts of assessment of the surgical patient, the alterations in homeostasis and the associated risks involved, caring for post-operative patients becomes an interesting challenge that can readily be met by today's surgical nurse
NS263 Hughes E (2004) Principles of post-operative patient care. Nursing Standard. 19, 5, 43-51. Date of acceptance: July 12 2004.
For related articles visit our online archive at: www.nursing- standard.co.uk and search using the key words above.
TIME OUT 1
Think of a surgical patient with a low systolic blood pressure who you looked after recently. Consider the potential causes of hypotension and list any changes in vital signs or subtle changes in their character such as the way the patient acted or the way he or she responded to you.
TIME OUT 2
Consider the use of electronic equipment in your clinical area to measure a patient's vital signs. By relying on this equipment to monitor a patient's heart rate could it be possible that potential arrythmias and ensuing cardiogenic shock could go unnoticed? Discuss your thoughts with your colleagues.
TIME OUT 3
Make a list of the body's fluid compartments. Consider how fluid shifts from one compartment to the other and make a note of the differences between these mechanisms.
TIME OUT 4
Go back to the list you made in Time Out 3. List the common fluids you use in your clinical area and identify which body fluid compartments they are used for and why.
TIME OUT 5
Pulse oximetry can provide incorrect readings. Make a list of the physiological causes or equipment problems that could lead to inaccurate oxygen saturation readings for patients in your care.
TIME OUT 6
How does pain occur in the body? Use a textbook of your choice and outline a brief summary of the physiological mechanisms for pain and how these mechanisms are affected by surgery.
TIME OUT 7
Consider the use of post-operative analgesia in your clinical area and the effectiveness of the methods of pain management in the post-operative period. Do you ever feel that the patient's pain is inadequately controlled? What are the reasons for this? Discuss your thoughts with your nursing and medical colleagues and make an action plan to improve the patient's pain experience, if necessary.
TIME OUT 8
Consider the use of thrombus prophylaxis in your clinical area. List the methods of prevention used and reflect on the evidence for these particular interventions.
TIME OUT 9
Now that you have completed the article you might like to write a practice profile. Guidelines to help you are on page 56.
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Elaine Hughes RGN, BSc(Hons), MEd, is senior lecturer, pre- registration adult nursing, Faculty of Health, Edge Hill College of Higher Education, Liverpool. Email: Hughese@edgehill.ac.uk
Copyright RCN Publishing Company Ltd. Oct 13-Oct 19, 2004