|• The patient is fully conscious, responding to voice or light touch, able to maintain a clear airway and has a normal cough reflex|
|• Respiration and oxygen saturation are satisfactory (10-20 breaths/minute and SpO2>92%)|
|• The cardiovascular system is stable with no unexplained cardiac irregularity or persistent bleeding|
|• The patient’s pulse and blood pressure should compare with normal pre-operative values or should be at a level corresponding to planned post-operative care|
|• There should be adequate control of pain and vomiting with suitable analgesic and anti-emetic regimens prescribed|
|• Temperature should be within acceptable limits (>36°C)|
|• Oxygen and fluid therapy should be prescribed when required|
Monitoring of patients allows routine data to be collated and trends established, therefore making it more straightforward to detect any clinical deterioration. It also allows a patient’s response to treatment to be evaluated. Common parameters include temperature, pulse rate, blood pressure, respiratory rate, urine output, peripheral oxygen saturation and pain scores .
These variables should be measured multiple times during the day, depending on the type of surgery involved. Other examples of monitoring include ECGs, arterial blood gas analysis (ABGs) and central venous pressure (CVP) monitoring . In addition, assessment of drainage and bleeding should also be performed routinely .
As the main significant post-operative complications in general surgical patients are cardiovascular and respiratory in nature, it is sensible that cardiorespiratory monitoring be made a priority . In general, maintaining a patient’s heart rate and blood pressure within normal limits will result in a satisfactory outcome. However, there are no clinical studies to indicate what is normal with respect to heart rate and blood pressure for individual patients in the post-operative period .
Hypertension is common post-operatively and can be due to various causes including pain, anxiety and discontinuing antihypertensive medication. Guidelines by The American College of Cardiology/American Heart Association  recommend deferring surgery if the diastolic pressure is above 110 mm Hg and systolic is above 180 mm Hg. No such guidelines exist in the UK however.
Hypotension is also common post-operatively and has been defined as a systolic blood pressure below 90 mmHg . Causes include hypovolaemia due to bleeding or dehydration, or drug therapy.
Myocardial ischaemia in the first 48 hours after an operation is the single most important predictor of serious cardiac events, including cardiac death, myocardial infarction, unstable angina, congestive heart failure and serious arrhythmias . High risk procedures with a risk of cardiac event greater than 5% include cardiac and vascular surgery, or major pelvic/GI surgery in the presence of pre-existing vascular disease. The majority of elective orthopaedic surgery is classed as intermediate risk, with a cardiac risk of less than 5% .
Pulmonary complications are an important and common cause of post-operative morbidity and mortality and are particularly common after major abdominal and thoracic surgery. Risk factors for the development of post-operative pulmonary complications include high body mass index (BMI), smoking status and the presence of COPD . Others include pre-operative respiratory illnesses, Intensive Care Unit (ICU) stay and mechanical ventilation in the post-operative period . In order to adequately observe respiratory function and to identify post-operative respiratory complications the respiratory rate, heart rate and conscious level should be monitored routinely. Indicators of respiratory complications include respiratory rate <10 or >25 breaths per minute; pulse rate >100 beats per minute and reduced conscious level.
Patients in whom there is a suspicion of post-operative pulmonary complications should have an arterial blood gas analysis, a sputum culture and ECG. A CXR should be performed on suspicion of major collapse, effusions, pneumothorax or haemothorax. Generally accepted diagnostic criteria for respiratory failure, pulmonary infections and acute respiratory distress syndrome (ARDS) are summarised in Table 33 .
Post-operative pulmonary complications can therefore be recognised early if vital signs are recorded accurately in the post-operative period. Any deterioration in these values should then necessitate the need for further investigations such as x-rays and ABGs.
Fluids & Electrolytes
The standard principles of fluid balance in the post-operative patient are to correct any pre-existing deficits, to replace unusual losses (e.g. from surgical drains, pyrexia) and to use the oral route wherever possible as there is not infrequently a delay in commencing oral intake after surgery. Particular patient groups susceptible to fluid or electrolyte disturbances include the elderly, those with pre-existing cardiovascular/cerebrovascular/renal disease and patients who have suffered a peri-operative myocardial ischaemic event .
In order to detect fluid and electrolyte abnormalities, patients must have their vital signs checked regularly. Hypotension, tachycardia, oliguria, confusion and tachypnoea may all be indications of hypovolaemia but also have other causes, including sepsis. Whenever a post-operative patient is hypovolaemic, it is important that haemorrhage be considered and to actively exclude this before attributing hypovolaemia to another cause .
Potential causes of hypovolaemia include haemorrhage, diarrhoea and vomiting, polyuria and fluid losses via drains. On the other hand, causes of fluid overload include excessive intravenous fluid administration and poor renal or cardiac function . This should be avoided as consequences may include pulmonary oedema. It is thus important to regularly check patients’ vital signs when administering intravenous fluids, so that it can be recognised early if the patient is getting too much or too little.
Sepsis is the systemic inflammatory response to infection and represents a progressive response to infection leading to a generalised inflammatory reaction and eventually end-organ dysfunction and/or failure . The development of systemic sepsis in a post-operative patient marks a serious decline in their condition. Therefore, early identification of patients at risk of developing sepsis and subsequent management is paramount  (see Table 44). Matot et al.  explain that some of the clinical features to look out when identifying sepsis include fever, signs of peripheral vasodilation, altered mental state, leucocytosis/neutropenia and unexplained tachycardia, tachypnoea or hypotension. Early identification and appropriate treatment of sepsis improves outcome . Without prompt intervention, severe sepsis may ensue, which has a mortality rate of 20-50% .
Following shoulder surgery, particularly highly invasive procedures such as total shoulder arthroplasty, reverse shoulder arthroplasty, or hemiarthroplasty, a thorough neurovascular assessment should be conducted. Circulation, sensation and movement (CSM) are evaluated by assessing the shoulder, elbow and wrist . Motor and sensory examination findings may be difficult to determine in the immediate post-operative period however, as regional blocks are frequently used. As a result, regular assessments are encouraged to demonstrate return of function. Assessment of all major nerves of the upper limb should be conducted, including the axillary nerve which is the most common nerve to be injured during shoulder surgery .
Post-operative pain can have a significant effect on patient recovery. Since the introduction of Patient-Controlled Analgesia (PCA) in the early 1980s, the daily management of post-operative pain has been enhanced. Patients using PCAs administer and titrate the dose to their own needs using a small microprocessor-controlled pump. Morphine is the most commonly used intravenous drug for PCA, however other opioids have been used. The most frequently observed adverse effects of opioid-based PCA are nausea and vomiting, pruritus, respiratory depression, sedation, confusion and urinary retention .
Other options available for post-operative analgesia include intrathecal and epidural analgesia. These may be provided either by using opioids, local anaesthetics or a combination of both. Intrathecal opioids are relatively straightforward to administer and can provide pain relief for twenty four hours or more after a single injection of intrathecal morphine. Epidural analgesia has been shown to be more effective than parenteral opioid administration and intravenous PCA for major surgery . However, this route of administration increases the risk for complications related to the indwelling epidural catheter, including dislodging, kinking or migration within the epidural space.
Opioids are commonly used in the post-operative period. Commonly used agents include morphine, fentanyl and pethidine. Intravenous infusion administration results in a more constant blood level however . Oral opioids can be very effective and can be used to rapidly wean a patient off parenteral therapy, thereby allowing earlier discharge from the hospital. Oxycodone as a controlled-release tablet can provide good pain control for up to 12 hours.
Other methods of providing analgesia also exist. A Cochrane review in 1998 concluded that paracetamol can be used for post-operative pain relief. Several reviews have since supported this, suggesting that paracetamol can provide effective pain relief for up to four hours post-operatively with few adverse side effects [40, 41]. Non-steroidal anti-inflammatory drugs (NSAIDs) can also be added to opioid treatment post-operatively as this can reduce morphine requirements and opioid-related side effects in the early post-operative period .
Wound infiltration with a local anaesthetic is a simple, safe, and attractive technique in the control of post-operative pain. Several randomised, controlled studies involving minor surgical procedures have discovered that wound infiltration with local anaesthetic provides superior analgesia, better pain scores, and superior reduction in opioid consumption compared with placebo [43, 44]. Long-acting local anaesthetics such as ropivacaine or bupivacaine are preferred as the analgesic effect is longer.
Interscalene brachial plexus blocks, either alone or combined with a general anaesthetic, are also a useful technique which can be employed to provide excellent post-operative analgesia for patients undergoing shoulder surgery . Fredrickson et al. in 2010  discovered during their review that continuous interscalene block incorporating a local anaesthetic infusion combined with PCA is the most effective analgesic technique following both major and minor shoulder surgery.
Thromboprophylaxis after elective shoulder surgery is a debatable issue as venous thromboembolic events (VTE) are so rare. There are no large-scale randomised trials published on rates of VTEs, although these are thought to be very low. The risk of a pulmonary embolism (PE) ranges from 0.2% to 2% in the literature with mortality rates of 1% . Jameson et al.  discovered that since the introduction of NICE guidelines in 2007 recommending the use of chemical agents in shoulder surgery, rates of VTE events did not change. As such, chemical VTE prophylaxis may not be required in shoulder surgery. Despite this, NICE continues to recommend thromboprophylaxis for high-risk shoulder surgery, extrapolating data from hip and knee replacements.