This article has been taken from an MSc module initially written by Dr Brian Jenkins, Senior Lecturer in Anaesthetics and Intensive Care and Honorary Consultant Anaesthetist, Department of Anaesthetics, Intensive Care and Pain Medicine, Cardiff University and has subsequently been updated and expanded by Dr Sarah Fox. Sarah is currently working in Psychiatry of Older Adults, and she continues her longstanding interest in pain management (Sarah previously worked in a pain clinic and then Bath Centre for Pain Services).
Sarah is involved in a project with Bristol PCT, called PAIN (Pain Assessment in Nursing homes) looking at more effective management of pain in people with dementia. She also has an interest in pain and depression/anxiety disorders in patients of all ages. Through her own personal experience and her ongoing work with support groups for patients with chronic pain around the world, she has interests in iatrogenic conditions and medically unexplained symptoms.
This article discusses the hospital management of someone who has a problem with substance misuse. Management issues are considered with advice regarding history taking, examination, pain management, methadone maintenance, buprenorphine issues and then managing the person in a variety of secondary care settings.
This article covers general points about the management of substance abusers in a hospital environment, from their admission to hospital and the modes of presentation, through to their discharge and follow-up. It is important to remember that managing patients with substance abuse may be problematic and in fact, health care professionals may exacerbate problems in their attitude to the patient who is a substance abuser. Health care professionals and drug using patients have been shown to display mutual mistrust, especially concerning opioid prescription . Health care professionals fear of deception, inconsistency and avoidance interacts with patients’ concern that they are mistreated and stigmatised .
Many substance abusers are admitted to hospital via the A & E Department as a result of medical complications associated with their habit. For regular users of Class A drugs and intravenous users in particular, this is likely to be a common occurrence.
A recent study  found that substance misusers presenting to the emergency department experience high levels of pain.
Trauma is a common reason for admission in many substance abusers. Infection is another typical trigger for admission: patients tend to present at a late stage, and septicaemia is common because of poor immune response.
Medical problems related to intravenous drug abuse are also common. Hyperthermia, cardiovascular instability or convulsions may be the presenting symptoms of recent cerebral stimulant intake. More dramatic presentations include sub-arachnoid haemorrhage, myocardial infarction, or ruptured aortic aneurysm. Acute onset confusion may be a side effect of most abused drugs, and in all cases of altered perception and frank hallucinations, substance abuse should always be considered in the differential diagnosis.
Chronic substance abuse, particularly intravenous injection may be associated with major organ failure, including heart failure, liver failure and renal failure. Injection of some substances (e.g Temazepam or Fentanyl) has been associated with embolism that can cause whole limb ischaemia or even death.
Opioid (narcotic) abusers often try to get themselves admitted to hospital in order to obtain drugs. They may try various strategies, often including claiming a recurrence of a condition they have already experienced, knowing that opioids may be prescribed to treat pain. They may fabricate painful symptoms, often in a highly convincing manner. They may claim to have run out of regular medication and be unable to access replacements (presenting out of hours) and occasionally may even be open about their addiction. Typically, these individuals tend to rotate through a number of different hospitals to avoid detection.
Any patient may be reticent about revealing personal information, especially if they fear a negative outcome. Inaccurate reporting may be a deliberate attempt to obscure the origin of but in prolonged alcohol misuse, there may be a type of dementia which presents with confabulation, with the patient ‘making up’ answers to questions in an attempt to conceal the cognitive deficit.
Certain presentations are commonly associated with substance abuse, thus creating an extra line of enquiry to direct the history and examination. These include admission in an unconscious or confused state, or a history of sudden collapse or convulsions with no known medical cause. During the history, more subtle symptoms, such as recent personality changes may also indicate a problem: these may only be elicited by taking a collateral history from relatives, friends or other professionals (GP, police etc.). The examination may reveal the presence of conditions that are known to be associated with drug abuse, such as liver disease, self-neglect, malnutrition and secondary infection. This may suggest appropriate investigations (e.g. blood tests) to provide additional evidence to establish a diagnosis.
Following emergency admission, there may be unwillingness to supply blood and urine samples for fear of detection and prosecution. Self-discharge may be preferred rather than to risk detection of the habit. Other reasons for self-discharge may, of course, may be related to their need to maintain intake of the abused substance.
If a drug habit is admitted to, an accurate history as possible should be obtained with regard to the dose and frequency of the abused drug, other drugs ingested (including medical drugs), history of previous admissions to hospital including detailed histories of surgical and anaesthetic procedures and previous problems identified. The accuracy of the history and particularly recent intake will help to identify any potential problems.
Given that history is not always reliable, a detailed examination is vital: if the patient is unco-operative, this should raise the index of suspicion.
Behaviour: it can be difficult and perhaps misleading to interpret patient behaviour but often this is precisely the first aspect of the examination that strikes the clinicians involved in the care.
Eye signs, such as pupil constriction in opiate use, may be present. Severe malnutrition and poor dental condition may be evident in some individuals, particularly chronic opioid abusers.
Solvent abuse may be noticeable due to peri-oral lesions.
Skin signs of intravenous abuse are obvious if specifically looked for, but in some cases the individuals have been careful to avoid detection of the habit by hiding the puncture sites. Less accessible veins may be used in preference to those over the anterior aspect of the forearm. These may be leg veins, veins on the upper arm or in more exotic locations such as the dorsum of the penis. Puncture sites may be obscured by tattoos, scars, bandages or clothing. Anything that is removable should be removed if possible. Superficial abscesses or cellulitis may be present.
Smokers may have a degree of cyanosis if they have respiratory of vascular problems. Peripheral cyanosis is seen in blue extremities.
Liver stigmata may be seen in alcohol abusers. These include spider naevi, palmar erythema, and in severe cases, jaundice. There may also be a hand tremor.
Anabolic steroid abusers often have a characteristic distribution of muscle mass with gross enlargement of upper arm and leg muscle blocks. The tension in the muscles may be so pronounced as to prevent full limb extension. Weight distribution in alcoholics is sometimes the reverse of this, with axial fat and poor development of limb muscles.
Respiratory rate is influenced by many abused drugs, with (generally) an increase in respiratory rate following recent intake of cerebral stimulants or hallucinogenics, and a decreased rate with cerebral depressants (including opioids and alcohol).
Drugs that are smoked can produce respiratory problems such as expiratory wheeze and chronic cough. There may be signs of pneumonia.
High blood pressure and heart rate, especially if associated with dysrhythmias, may indicate recent intake of cerebral stimulants, or may be a symptom of withdrawal seen with many abused substances. These signs are obviously not specific, but may be useful in conjunction with other symptoms to aid diagnosis. Murmurs may be present in intravenous drug abusers, and may be a sign of infective endocarditis.
In some patients hepatic enlargement may be present. It may be related to some forms of substance abuse such as chronic opioid ingestion, or may be secondary to hepatitis. A shrunken hard liver suggests scarring and indicates possible cirrhosis. The liver may also be tender to palpation, and other signs of liver impairment may be present. These include abdominal ascites, jaundice and peripheral vascular changes such as spider naevi.
Neurological signs are common in substance abusers, but as with examination of other systems are usually not specific. Common symptoms are exaggerated physiological tremor, and increased reflexes that can be associated with cerebral stimulants. Nystagmus may be present with a number of chronic abuse states including alcoholism and hallucinogen abuse. Loss of co-ordination is a feature of most abused substances. Chronic alcohol misuse can cause abnormal gait due to effects on the spinal cord (subacute combined degeneration). Acute intoxication obviously causes ataxia. Occasionally more specific neurological symptoms are present. These are generally small-print diagnoses e.g. transverse myelitis from chronic opioid abuse.
Problems with analgesia
Analgesic management is usually difficult in substance abusers, with particular problems in opioid abusers. Chronic abuse increases tolerance to opioids, so that a higher dose than average will be required. However, there is always the risk that inappropriate amounts will be requested. All patients with a history of drug abuse should be assessed and treated individually.
Patients who have drug abuse issues present particular difficulties for healthcare professionals in pain management. Areas for concern, which may affect clinical pain management in this group of patients, include:
- Dual diagnosis
- Methadone maintenance treatment
- Active drug users.
- Patients in drug free recovery
- Chronic pain patients misusing analgesics
- Dual diagnosis refers to the co-existence of substance misuse and a psychiatric disorder.
Seventy two percent lifetime comorbidity exists between substance abuse and a psychiatric disorder . Patients with a psychiatric disorder and history of drug abuse may experience pain from psychiatric causes and have increased pain sensitivity from opioid use or they may have more complaints of pain as part of their psychiatric illnesses such as depression or anxiety. They may also attempt to self- treat the symptoms of their psychiatric disorder with opioids and other illegal substances.
Methadone was first synthesized as an analgesic by a German chemist during World War 11 when the countries opium supply was cut off. It is a long acting opioid agonist, which is metabolised in the liver . Excess is stored in the liver, blood stream and in body fat; this results in a long elimination half-life (20-45 hours). Its metabolism is highly unpredictable even within individual patients, and can vary from day to day.
Methadone maintenance was developed as part of the Harm Reduction strategy which became policy partly in response to AIDS. Other aspects of the programme include provision of clean needles etc. to reduce infection risk.
Methadone is prescribed for maintenance usually on a once daily basis, due to its long half-life.
Methadone occupies the opioid receptors and produces no symptoms of euphoria or intoxication (at stable doses). Methadone relieves the symptoms associated with opioid withdrawal and the craving for opiates. Methadone maintenance is not used to treat acute pain but some patients with chronic pain may be treated with methadone at low dose twice a day.
Methadone maintenance therapy can affect how pain is tolerated in drug abusers group, and therefore how pain is managed: detoxification from opioids does not reset pain perception for at least 1 month . Abstinent, formerly opioid-dependent patients may continue to demonstrate abnormal pain perception months after detoxification from methadone .
Patients, who are on methadone maintenance and have for example postoperative pain, may identify to staff that they have pain and may request analgesia earlier than perhaps a ‘typical’ patient having the same operative procedure. The possible inability of this group of patients to tolerate pain, due to the pharmacological effects of methadone, must be appreciated by staff.
The implications for clinical practice are that a hyperalgesic response to pain must be taken into account when prescribing analgesia for patients on methadone maintenance, and that the methadone does not in these circumstances provide analgesia.
There are three possible methods of management:
Substitute methadone with alternative opioid analgesia to control pain and prevent withdrawal. However, short acting opioids tend to be metabolised more rapidly in patients with a history of opioid abuse and tolerances to the analgesic effects develop faster, so that pain relief may be suboptimal and there may be withdrawal symptoms.
Increase the dose of methadone to control pain as well as prevent withdrawal. However producing effective and sustained analgesia with methadone even in non-opioid dependent patients requires at least three doses per day as methadone’s analgesic effects are relatively short acting, 4-6 hours. Methadone maintained patients will develop tolerance to the analgesic effects so that high doses would be required, which may cause problems on discharge home.
Continue with baseline methadone maintenance; administer frequent doses of short acting analgesia. Increase analgesia as required to control pain . This third option is often preferred by clinicians. Patients who are methadone maintained are fully tolerant to the maintenance dose and will get no analgesic effects from the methadone maintenance. Due to cross-tolerance, short acting opioid analgesia may be required in larger and more frequent doses than in patients not on methadone maintenance treatment.
The other drug used in opiate abusers is Buprenorphine which is also an analgesic that has a partial opiate agonist and partial antagonist effect. It is given as Subutex or in combination with Naloxone (Suboxone) for addiction but as a patch (BuTrans or Transtec) for chronic pain or buccally (Temgesic) for more acute pain.
Buprenorphine may also be used recreationally, typically by opioid users, often by inhalation. Recreational users of Suboxone report a euphoric rush similar to other opioids in addition to a slight “upper”-like effect but those using buprenorphine/Suboxone for opioid addiction therapy find that there is little benefit compared with taking a tablet sublingually.
Many recreational users report withdrawal symptoms. Due to the high potency of tablet forms of buprenorphine, only a small amount of the drug need be ingested to achieve the desired effects.
Although some people do use Buprenorphine for purely recreational reasons, the majority of its illicit users use it for addiction therapy. Many people report it being effective in preventing withdrawals in-between doses of their opiate of choice.
Peri-operative management. The basics of management are as in any patient, the anticipation of problems, good monitoring and prevention of instability during and after the procedure. Obtaining as much information as possible from the patient, assists in anticipating and effectively treating problems as well as reassuring the patient that their care is of importance. Reticence may mean that the drug problem is only revealed by problems during anaesthesia such as frequent dysrhythmias or other episodes of cardiac instability. In this situation, problems must be managed symptomatically during surgery and anticipating postoperative problems such as withdrawal.
There are several ways to tackle this problem, but most involve using supplementary analgesic techniques in order to avoid or at least minimise the use of opioids to control perioperative pain. Analgesics with partial antagonism effects at opioid receptors should be avoided, as administration of these may produce or exacerbate withdrawal symptoms in chronic opioid abusers. These drugs include buprenorphine, pentazocine, nalbuphine and meptazinol. It is best to stick with non-steroidal anti-inflammatory drugs (NSAIDS), local anaesthetics and pure opioid agonists such as morphine and fentanyl for pain relief.
For minor surgery, and particularly operations that are able to be accomplished on a day-surgery basis it may be possible to avoid opioids completely. NSAIDs, either on their own or in combination with local anaesthetic blocks are usually the preferred method of analgesia. In some cases supplementary opioids will be required, either because the surgery is not amenable to local anaesthetic supplementation or because of uncontrolled pain.
However, concurrent administration of NSAIDs will reduce opioid requirements and make it easier to control pain without recourse to large amounts of opioids. Following the surgery, the usual programme of addiction or withdrawal from addiction may then be rapidly resumed.
For major surgery, it is rarely possible to control pain with NSAIDs alone. If the surgical site is a limb or lower abdomen where pain can be effectively controlled by local analgesia, this may be the method of choice, both for intra-operative and postoperative pain relief. General anaesthesia may also be avoided with a co-operative patient. Local analgesia may still be useful for post-operative analgesia even in situations where it is not possible to avoid general anaesthesia. Such situations include multiple operative sites or extensive incisions (such as following major trauma), head and neck surgery, thoracic and upper abdominal surgery. Unfortunately, there are many other situations in the management of substance abusers where local anaesthesia is probably best avoided.
Infection near the proposed injection site deranged clotting mechanisms or neurological deficits that involve the planned operative field are some of these situations. For these and many other reasons, opioids often have to be given in the perioperative period in order to adequately control pain.
If the patient has an uncontrolled opioid addiction, some opioids will be required in order to avoid withdrawal symptoms – the perioperative period is not a good time to initiate opioid withdrawal. The amount of opioid that needs to be given in order to both control pain and to prevent withdrawal will usually be a hot debating topic between the patient and the hospital staff. It is necessary to estimate the patient’s self-administered opioid intake.
However, it is often difficult to rely entirely on the patient’s recollections of this, so communication with the patient’s GP, psychiatrist, social worker or other responsible health care professional associated with their normal care is usually necessary. As a rule of thumb, the amount of analgesia required is the patient’s normal dose of opioid plus what is normally required for postoperative analgesia. This will obviously need to be tailored for every patient, but if the apparent dose required deviates significantly from the expected dose, there may be a need to review the analgesic strategy.
Although there is very little research to support the use of Patient Controlled Analgesia (PCA) in this group of patients, the administration of opioid analgesia via a PCA machine avoids confrontation between patients and staff , and is the method of clinical choice of experts in addiction and pain medicine.
There may be the issue of mental capacity in intoxicated patients: informed consent cannot be given by someone who lacks capacity. It may be necessary to make a best interests decision in emergency situations or wait for capacity to be regained if time allows.
Some patient may experience persistent memory loss due to their drug abuse (, ). Therefore information may have to be given in small amount and repeated frequently in order for informed consent to treatment to be achieved.
The ongoing abuse of illegal drugs
Patients who are active drug abusers may be tempted to continue to abuse drugs while in hospital. Around the time of surgery, the patient may bring their own drugs with them or friends/relatives supplying illegal drugs, including injecting them through the patient’s intravenous cannula.
A clear strategy for pain management should be established with the patient. When possible their close relative or friend should also be kept informed of how pain and withdrawal will be managed. This should provide reassurance that a history of drug abuse will not be an obstacle to providing adequate pain management, and that withdrawal will be prevented. However staff should also make it clear that if the patient continues to abuse illegal opioids their safety cannot be ensured therefore the administration of analgesia may have to be restricted, and the police will be involved.
Chronic pain management
There may be complex issues related to treating substance misuse in treating chronic pain patients. There are different groups of patients:
Patient with chronic pain but no previous drug history who misuses prescription analgesia
Patient with chronic pain who develops a drug habit or alcohol misuse in an attempt to manage the problems of chronic pain (physical and psychological pain)
Patient with a history of substance misuse who develops chronic pain after trauma or illness which may be related to the drug use or alcohol, but is no longer misusing
Patient continuing an established substance misuse
There are a number of assessment tools that attempt to identify ‘at-risk’ patients. Turk et al  suggested that there is little evidence that these are effective. No reliable evidence exists on accuracy of urine drug screening, pill counts, or prescription drug monitoring programmes; or clinical outcomes associated with different assessment or monitoring strategies .
Prescription of opioids in the long term remains contentious asthe safety and efficacy is uncertain as is the propensity for these drugs to cause problems of tolerance, dependence and addiction. Opioids rarely afford ccomplete relief of pain, so the goal of therapy should be to reduce symptoms sufficiently to support improvement in physical, social and emotional functioning. 80% of patients taking opioids will experience at least one adverse effect, some of which are persistent. These should be discussed with the patient before treatment begins.
In general, modified release opioids administered at regular intervals should be used in the management of patients with persistent pain although a more flexible dosing regimen using immediate release preparations may be necessary and acceptable in some cases.
Patients with current or previous history of substance misuse or with a psychiatric disorder (such as depression) have a higher risk of developing problems with opioid use. These patients should be managed collaboratively by pain and/or addiction specialists and GPs.
Drug misusers, especially those with severe dependency, may have many other problems, including involvement with the criminal justice system, poor educational and employment histories, mental health issues, family problems, and housing need. Similarly, pain causes a variety of problems with far-reaching, biopsychosocial consequences.
Managing patients in pain who have substance misuse issues is therefore a complex problem. Clinical guidelines from the Department of Health  emphasis that it is not good practice for primary care teams to treat drug misusers without the support of a specialist team.
Similarly, the Royal College of Psychiatrists recommends multi-disciplinary, specialist treatment to tackle complex alcohol problems, particularly if there is psychiatric comorbidity.
Effective management of this group of patients may involve shared care with primary health care, liaison with mental health services, and in some cases, the criminal justice system.
The relationship between the health professional and the patient who is a substance misuser can be a tricky one but a focus on education could lead to an improvement in the management of this group of patients (, ). In particular, this may tackle opiophobia that affects the provision of analgesia and may lead to poor pain management.
Bell & Salmon  looked at academic and clinical literature on pain management and addiction providing guidance on the provision of opiates for the relief of chronic pain, finding clear distinctions between the ‘deserving pain patient’ and the ‘undeserving addict’, which, as the authors comment, serves “both to further stigmatise people labelled as ‘addicts’ and delegitimise claims to pain they might voice.”
Aside from the humanitarian issues of providing pain relief, effective prescription of opioids can be beneficial in terms of reducing the risk of misuse: in addicts as well as non-addicted patients.
The other major issue is the pain patient whose analgesic use becomes maladaptive, probably initially accidentally. The risks of addiction in pain patients have been overstated by many doctors and continue to be a source of concern to patients, families, and healthcare professionals.
However, provided analgesics are given in a regimen of doses appropriate to treat pain effectively but not excessive, then the risks remain relatively low (less than 20%). Unfortunately, the psychological distress inherent in chronic pain of all types, often occasions the use of analgesics to alleviate the anxiety, depression and insomnia associated with pain. In these circumstances, opiates are likely to have a different effect on neurotransmitters, and tolerance can develop rapidly. Understanding these issues is imperative in developing a good therapeutic relationship, working with the patient for optimal pain relief with minimal dependence.
Although the 2008 National drug strategy stated that“The goal of all treatment is for drug users to achieve abstinence from their drug – or drugs – of dependency, ”in patients with chronic pain, it may not be appropriate to with-hold drugs that can alleviate pain and distress. In this situation, a carefully devised management plan with co-operation between healthcare professional and patient is vital.
You may be interested in reading more about this subject area read Dunbar and Katz , Dickey et al , Dobbin .
The British Pain Society has issued a consensus statement on management of drug misuse available at: http://www.britishpainsociety.org/book_drug_misuse_main.pdf
Royal College of Psychiatrists Advice to commissioners and purchasers of modern substance misuse service 2002 available at: http://www.rcpsych.ac.uk/files/pdfversion/cr100.pdf
For further information on British Pain Society’s recommendations for long-term opioid prescription, see 2010 publication at: http://www.britishpainsociety.org/book_opioid_main.pdf
See also: See also Gallagher & Rosenthal  Chronic pain and opiates: balancing pain control and risks in long-term opioid treatment.
UK guidelines on clinical management Department of Health – National Treatment Agency for Substance Misuse  Drug Misuse and dependence: http://www.nta.nhs.uk/publications/documents/clinical_guidelines_2007.pdf.
For further information on the Mental Capacity Act 2005, see: http://www.publicguardian.gov.uk/mca/mca.htm
You can find out more about the use of Methadone and Buprenorphine for managing opioid dependence from NICE Guidelines at http://www.nice.org.uk/TA114
For information on drug Misuse and Dependence see the Department of Health (2007) UK Guidelines on Clinical Management: http://www.dh.gov.uk/en/Publicationsandstatistics/Publications/PublicationsPolicyAndGuidance/DH_4009665
You may also want to read: Pain and substance misuse: improving the patient experience. British Pain Society (2007): http://www.britishpainsociety.org/book_drug_misuse_main.pdf
You may also want to read: Understanding Addiction – How Addiction Hijacks the Brain http://www.helpguide.org/harvard/how-addiction-hijacks-the-brain.htm
For information on the effects of illegal drugs on the heart visit: https://www.acls.net/effects-of-drugs.htm
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