The Royal Marsden Hospital Manual of Clinical Nursing Procedures - Lisa Dougherty [331]
Evidence-based approaches
Rationale for effective acute pain control
There are several reasons why pain needs to be well controlled following surgery, not least that patients have a right to expect adequate treatment of pain and that all members of the healthcare team have an ethical obligation to provide it (Audit Commission 1997). It is now known that undertreatment of acute pain coupled with the physiological response to surgery, known as the stress response, can have a number of adverse consequences (Macintyre and Schug 2007).
Pain can have long-lasting effects on the central nervous system, leaving an ‘imprint’ if pain is poorly controlled which may mean that future episodes of pain are difficult to control (Carr 2007). Uncontrolled pain can lead to increased anxiety, fear, sleeplessness and muscle tension which further exacerbate pain. It can delay the recovery process by hindering mobilization and deep breathing, which increases the risk of a patient developing a deep vein thrombosis, chest infection or pressure ulcer. Pain can also lead to significant delays in gastric emptying and a reduction in intestinal motility (Macintyre and Schug 2007). With severe pain, activity of the sympathetic nervous system and the neuroendocrine ‘stress response’ causes platelet activation, changes in regional blood flow and stress on the heart. These can lead to impaired wound healing and myocardial ischaemia (Macintyre and Schug 2007). There is evidence to suggest that in the long term, poorly controlled acute pain may lead to the development of chronic pain. Perkins and Kehlet (2000) established that moderate to severe acute postoperative pain was a predictor for developing chronic pain after breast surgery, thoracic surgery and hernia repair.
Methods of pain assessment
Assessment is a key step in the process of managing pain. The aim of assessment is to identify all the factors, physical and non-physical, that affect the patient’s perception of pain. A comprehensive clinical assessment is essential to gain a thorough understanding of the patient’s pain, select an appropriate analgesic therapy, evaluate the effectiveness of interventions and modify therapy according to the patient’s response.
Acute pain assessment for surgical patients
For surgical pain to be controlled effectively, pain must be assessed regularly and systematically. The process of pain assessment begins before surgery and continues through to discharge.
A number of psychosocial factors can influence pain. Pain is an individual, multifactorial experience influenced by previous pain events, beliefs about pain and pain management, anxiety, mood and culture (Macintyre et al. 2010). Patients may be anxious about the outcome of the surgery or how pain will be controlled, particularly if they have bad memories of previous pain experiences (Audit Commission 1997, Carr and Mann 2000). Anxiety in turn exacerbates pain by increasing muscle tension. Providing patients with appropriate support and information to address these concerns can reduce both anxiety and postoperative pain (Audit Commission 1997, Kalkman et al. 2003).
Assessment of pre-existing pain
Patients who have been taking regular opioid analgesics for a pre-existing chronic pain problem may require higher doses of analgesia to manage an acute pain episode (Lewis and Williams 2005, Macintyre 2001, Mehta and Langford 2006). It is therefore important to take a history of pre-existing pain and analgesic use so that appropriate analgesic measures can be planned in advance of surgery. This is particularly important for opioid-tolerant patients irrespective of whether opioid tolerance is due to analgesic therapy or recreational opioid drug use (Box 9.11).
Box 9.11 Key points for managing acute pain in opioid-dependent patients
Good communication: patients at risk should be identified at preassessment