Related Conditions

It is worth mentioning conditions that are similar to but not the same as POND. The term substance-induced psychotic disorder (SIPD) describes the circumstances when prominent psychotic symptoms (hallucinations and/or delusions) are the direct result of substance use.¹ They are distinct from independent co-occurring mental disorders and from POND. A substance may induce psychotic symptoms during intoxication (while the individual is under the influence of the drug) or during withdrawal (after an individual stops using the drug). Some episodes of POND may be missed by incorrect classification into this category.

A substance-induced psychotic disorder is caused directly by the effects of drugs. Common causes include alcohol, prescription medications, herbal remedies and toxins (insecticides). Numerous lists of drugs that may cause psychotic symptoms are published on the web.²

Some medication groups that may induce psychotic symptoms include anesthetics and analgesics, anticholinergic agents, anticonvulsants, antihistamines, antihypertensive and cardiovascular medications, antimicrobial medications, antiparkinsonian medications, chemotherapeutic agents, corticosteroids, gastrointestinal medications, muscle relaxants, nonsteroidal anti-inflammatory medications, other over-the-counter medications, antidepressant medications, and disulfiram.

Toxins that may induce psychotic symptoms include anticholinesterase, organophosphate insecticides, nerve gases, carbon monoxide, carbon dioxide, and volatile substances (such as glue, fuel or paint).

The speed with which drugs induce psychotic symptoms depends on the type of drug and the route of administration amongst other factors. For example, abuse of cocaine may produce psychotic symptoms within minutes of inhalation whilst psychotic symptoms from alcohol abuse may take days or weeks of intensive use.

The relative frequency of auditory, visual and tactile hallucinations may also vary according to the type of substance being abused. Auditory hallucinations (hearing voices), visual hallucinations, and tactile hallucinations commonly reflect alcohol-induced psychotic disorders. Persecutory delusions and tactile hallucinations (formication – insects crawling on the skin) are more frequently encountered when stimulants are abused.

References

1. Mental Disorders http://www.minddisorders.com/Py-Z/Substance-induced-psychotic-disorder.html
2. The Medical Letter Online http://secure.medicalletter.org/w1301c

The Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) reminds readers that this diagnosis can only be made when the psychotic symptoms are above and beyond what would be expected during intoxication or withdrawal and when the psychotic symptoms are severe. The criteria necessary for diagnosis of a substance-induced psychotic disorder in the DSMIV-TR are:

1.Presence of prominent hallucinations or delusions
2.Hallucinations and/or delusions develop during, or within one month of, intoxication or withdrawal from a substance or medication known to cause psychotic symptoms.
3.Psychotic symptoms are not actually part of another psychotic disorder (such as schizophrenia, schizophreniform disorder, schizoaffective disorder) that is not substance induced. For instance, if the psychotic symptoms began prior to substance or medication use, then another psychotic disorder is likely.
4.Psychotic symptoms do not only occur during delirium.

There is very little documented regarding prevention of substance-induced psychotic disorder. However, abstaining from drugs and alcohol or using these substances only in moderation would clearly reduce the risk of developing this disorder. In addition, taking medication under the supervision of an appropriately trained physician should reduce the likelihood of a medication induced psychotic disorder. Finally, reducing one’s exposure to toxins would reduce the risk of toxin-induced psychotic disorder. http://www.healthline.com/galecontent/substance-induced-psychotic-disorder

AANA Journal Course: Sorting through the Confusion: Adverse Cognitive Change After Surgery in Adults http://www.aana.com/newsandjournal/Documents/jcourse3-0811-p335-342cx.pdf

Acute postoperative psychosis has been known for many years and was often blamed on anaesthesia. ² Psychosis may develop from the presence of a drug and from withdrawal of a drug. It can also occur, in the case of anaesthetics, from the absence of the drug that should be there i.e. the anaesthetic fails. What happens if planned anaesthesia fails? Anaesthesia is no longer considered to be an all or none phenomenon. ³ There are different levels of anaesthesia.⁴ There is a growing consensus that intra-operative awareness is a spectrum of brain states. ⁵ A “level” of anaesthesia suitable for the stimulation associated with one part of a surgical procedure may be inadequate for another phase of the same surgery. The consequence is a level of arousal compatible with sensory perception, however transient. This may lead to levels of intraoperative awareness. ⁶ Recollection of events that occurred during the period that a patient is supposedly anaesthetized can occur. ⁷ This is not the same as recollecting dreams that occurred during this period, which is a much more common event, but is sometimes misinterpreted as recollections of actual events.⁸

Very rarely a planned general anaesthetic may fail in its intended purpose, resulting in a period of intraoperative awareness, a common cause for pre-operative anxiety. ⁹ Although the reported incidence of awareness in some studies is as low as 0.13%, from the 20 million anaesthetics administered in the United States annually, approximately 26,000 cases of awareness may occur each year. ¹⁰

For an accessible outline of this anaesthetic risk Dr. David Smith, Consultant Anaesthetist and Senior Lecturer at University Hospital Southampton has produced a leaflet for public consumption on behalf of the Royal College of Anaesthetists, London. He was the moderator for the Royal College of Anaesthetists National Audit Project 5 and a member of the Specialist Committee for NICE guidance on Depth of Anaesthesia Monitoring (2012). ¹¹

For a small minority who experience this phenomenon there are no distressing consequences but for the majority the psychological consequences of intraoperative awareness are well known. ¹² In one prospective study a third of patients experienced late psychological symptoms after an episode of intraoperative awareness. For just under half of these, the symptoms lasted for more than 2 months, and one patient had a diagnosis of post-traumatic stress disorder (PTSD). Predicting who may be most affected is difficult but acute emotional reactions were significantly related to late psychological symptoms (P<0.05). ¹³

Suicide shortly after surgery is extremely rare but not unknown. ¹⁴ In rare instances of acute postoperative psychoses some authors believe that a period of intraoperative awareness may precipitate post-traumatic stress disorder (PTSD) of such severity as to precipitate suicidal intentions.¹⁵ (Prof Michael Wang)

The mechanism that precipitates a suicide attempt in a patient during the postoperative period remains speculative. There is no evidence to suggest that awareness was responsible for the following or any other suicide whose details are available in the public domain. However, the tragic association between PTSD and suicide is becoming more widely recognised and its early recognition may prevent escalation.¹⁶

Case History

A patient had an operation to remove a malignant tumour on his brain. The operation went well but in the immediate recovery period the patient suffered from sporadic euphoric and paranoid episodes with delusions, believing himself possessed, before finally overwhelming his carers, breaking through and falling from a hospital window. ¹⁷ This patient had been lucid for 6 hours after his anaesthetic and the principle offending medication may have been a cortico-steroid (dexamethasone), which is known to occasionally produce an acute psychosis ¹⁸ or exacerbate existing conditions.¹⁹

Distressing intra-operative awareness, as well as PTSD and subsequent suicidal intent, has prompted investigation into quantifying the frequency of this event. It has also prompted the investigation and development of a means of gauging depth of anaesthesia worldwide.²⁰ It was hoped that an objective measure of depth of anaesthesia might enable anaesthetists avoid these complications.

National audits to investigate this phenomenon (NAP5: Accidental Awareness during General Anaesthesia) have been underway in the UK for a number of years. ²¹ ²² The results indicate that the incidence is much less than previously thought, though it is not non-existent. ²³ Geographical differences may exist with possibly lower incidences of this complication in Europe than the USA. ²⁴ Such differences may depend on what is being reported and the type of surgery involved. Various professional bodies have sought to inform the general public of the potential risks and to reassure them that a great deal of effort goes into preventing this phenomenon. ²⁵

References

1. The Royal College of Anaesthetists http://www.rcoa.ac.uk/system/files/PI-RISK8-AWARENESS-2013.pdf
2. Doyle JB. Post-Anæsthetic And Post-Operative Psychosis Br. J. Anaesth. (1928) 6 (1): 37-39
3. Prys-Roberts C. Anaesthesia: a practical or impractical construct? British Journal of Anaesthesia 1987; 59: 1341–5.
4. Pandit JJ. Monitoring (un)consciousness: the implications of a new definition of ‘anaesthesia’. Anaesthesia Volume 69, Issue 8, pages 801–807, August 2014
5. Escallier KE, Nadelson MR, Zhou D, Avidan MS. Monitoring the brain: processed electroencephalogram monitoring and peri-operative outcomes. Anaesthesia 2014; 69: 899–910.
6. Cook TM, Pandit JJ. NAP5: accidental awareness during general anaesthesia. Bulletin of the Royal College of Anaesthetists 2012; 72: 29–31.
7. Sebel PS et al. The incidence of awareness during anesthesia: A multicenter United States study.
Anesth Analg 2004;99:833–839.
8. Pollard et al. Intra-operative awareness – a review of 3 years data. Anesthesiology 2007; 106:269–274. .
9. McCleane GJ, Cooper R. The nature of pre-operative anxiety. Anaesthesia 1990; 45:153-155
10. Sebels PS, Bowdie TA, Ghoneim MM. The incidence of awareness during anaesthesia: a multi-centre United States study. Anesthesia and Analgesia 2004; 99:833- 839
11. The Royal College of Anaesthetists http://www.rcoa.ac.uk/system/files/PI-Risk8_1.pdf
12. Ghoneim MM, Block RI, Haffarnan M, Mathews MJ. Awareness during anesthesia: risk factors, causes and sequelae: a review of reported cases in the literature. Anesth Analg. 2009 Feb;108(2):527-35.
13. Samuelsson P, Brudin L, Sandin RH. Late psychological symptoms after awareness among consecutively included surgical patients. Anesthesiology 2007;106: 26 -32
14. http://www.dailymail.co.uk/news/article-2109386/Hospital-patient-plummets-40ft-death.html
15. Personal communication: Prof Michael Wang. Professor of Clinical Psychology. University of Leicester. 104 Regent Road, Leicester LE1 7LT +44(0)116 223 1648. FAX +44(0)116 223 1650
16. Krysinska K1, Lester D. Post-traumatic stress disorder and suicide risk: a systematic review. Arch Suicide Res. 2010;14(1):1-23.
17. http://www.leicestermercury.co.uk/Man-jumped-death-hospital/story-19260476-detail/story.html#eXxBUt4hoKyW8d1c.99
18. Koteswara CM and Pritish Patnaik P. Peri-operative dexamethasone therapy and post-operative psychosis in patients undergoing major oral and maxillofacial surgery. J Anaesthesiol Clin Pharmacol. 2014 Jan-Mar; 30(1): 94–96.
19. Jane P. Gagliardi, MD, MHS, Andrew J. Muzyk, PharmD, and Shannon Holt, PharmD When Steroids Cause Psychosis. Medical management of this side effect is complicated in rheumatology patients The Rheumatologist, October 2010
20. Practice advisory for intra-operative awareness and brain function monitoring: a report by the American Society of Anesthesiologists Task Force on Intra-operative Awareness. Anesthesiology 2006;104; 847-864
21. Pandit et al. A national survey of anaesthetists (NAP5 Baseline) to estimate an annual incidence of accidental awareness during general anaesthesia in the UK. Anaesthesia 2013; 68 :343–353.
22. http://www.niaa-hsrc.org.uk/article.php?newsid=153
23. http://www.aagbi.org/news/new-survey-reports-low-rate-patient-awareness-during-anaesthesia
24. http://www.aana.com/resources2/professionalpractice/Pages/Con-Anesthesia-Awareness-during-General-Anesthesia.aspx
25. McGrattan K, Smith AF. Risks associated with your anaesthetic, Section 8: Awareness during general anaesthesia. Information for patients: The Royal College of Anaesthetists, January 2006.

Depth of anaesthesia monitors

Attempts to design technology that enables anaesthetists to measure “depth of anaesthesia” have had mixed successes.¹ The main difficulty is interpreting the results obtained from the equipment. ² One such monitor is a device that generates a visible waveform representing the depth of anaesthesia – the bi-spectral index monitor. ³ An anticipated reduction in the incidence of intraoperative awareness or reduction in the use of anaesthetics in excess of their minimum requirements was not evident from the use of Bi-spectral index in another study. ⁴ In other studies the use of a device to measure the depth of anaesthesia produced a paradoxical outcome, favouring non-use of the bi-spectral index. ⁵

More recently Escallier and colleagues have reviewed the relationship between intraoperative monitoring of the brain and perioperative outcomes. ⁶ They point out that monitoring the brain during anaesthesia serves two purposes, the ultimate goals being avoidance of the negative outcomes that have been associated with both inadequate and excessive anaesthesia. Their review highlights the evidence for the role of bispectral index monitoring, in particular, in guiding anaesthetic management and influencing clinical outcomes, specifically intra-operative awareness, measures of early recovery, mortality and neurocognitive outcomes. The use of such monitors is controversial as there is little sound scientific proof of their efficacy, despite recommendations for their use by NICE. Their intended purpose is to reduce the incidence of awareness, thus avoiding PTSD and also avoid unnecessary depth of anaesthesia, which may also be associated with poor psychological outcomes. ⁷, ⁸, ⁹

Unfortunately the use of monitors is not associated with either a reduction in the incidence of awareness nor savings in the use of expensive anaesthetic agents. Alternative techniques have been employed that involve isolating the patients forearm from the effects of all anaesthetic and relaxant drugs by the simple expedient of obstructing the blood flow to the arm by means of a tourniquet. ¹⁰ Using this technique it was possible to demonstrate that some patients are perfectly capable of communicating with hand movements whilst suffering no distress from the surgery. Some were also able to recall the process whilst others were not. Pandit has proposed a state termed ‘dysanaesthesia’, which implies a degree of environmental awareness but is not associated with cognitive appraisal of distressing aspects of surgery (e.g. pain, inability to move), and may or may not be explicitly remembered. Experiments with the isolated forearm technique suggest that current pEEG devices are unreliable in detecting when patients are able to respond appropriately to a verbal command such as, ‘squeeze your right hand twice’. ¹¹

References

1. Monk TG, Weldon BC. Does depth of anesthesia monitoring improve postoperative outcomes? Curr Opin Anaesthesiol. 2011 Dec;24(6):665-9. doi: 10.1097/ACO.0b013e32834c7acf
2. Song D, Joshi GP, White PF. Titration of volatile anaesthetics using bi-spectral index facilitatesrecovery after ambulatory anaesthesia. Anesthesiology 1997;87; 842-848
3. http://www.modernmedicine.com/modern-medicine/news/technology-today-bispectral-index-monitoring
4. Avidan MS, Zhang L, Burnside BA, et al. Anesthesia awareness and the bi-spectral index. New England Journal of Medicine 2008;358;1097-1108
5. Avidan MS1, Jacobsohn E, Glick D, Prevention of intraoperative awareness in a high-risk surgical population. N Engl J Med. 2011 Aug 18;365(7):591-600. doi: 10.1056/NEJMoa1100403. Burnside BA, Zhang L, Villafranca A, Karl L, Kamal S, Torres B, O’Connor M, Evers AS, Gradwohl S, Lin N, Palanca BJ, Mashour GA; BAG-RECALL Research Group
6. Escallier KE, Nadelson MR, Zhou D, Avidan MS. Monitoring the brain: processed electroencephalogram monitoring and peri-operative outcomes. Anaesthesia 2014; 69: 899–910.
7. Chan MT, Cheng BC, Lee TM, Gin T. Coda Trial Group. BISguided anesthesia decreases postoperative delirium and cognitive decline. Journal of Neurosurgical Anesthesiology 2013; 25: 33–42.
8. Radtke FM, Franck M, Lendner J, Kruger S, Wernecke KD, Spies CD. Monitoring depth of anaesthesia in a randomized trial decreases the rate of postoperative delirium but not postoperative cognitive dysfunction. British Journal of Anaesthesia 2013; 110(Suppl. 1): i98–105.
9. Sieber FE, Zakriya KJ, Gottschalk A, et al. Sedation depth during spinal anesthesia and the development of postoperative delirium in elderly patients undergoing hip fracture repair. Mayo Clinic Proceedings 2010; 85: 18–26.
10. Pandit JJ. Isolated forearm – or isolated brain? Interpreting responses during anaesthesia – or ‘dysanaesthesia’. Anaesthesia 2013; 68: 995–1000.
11. Escallier KE, Nadelson MR, Zhou D, Avidan MS. Monitoring the brain: processed electroencephalogram monitoring and peri-operative outcomes. Anaesthesia 2014; 69: 899–910.

Central anticholinergic syndrome (CAS)

Acute psychosis is recognized as a feature of emergence from surgical anesthesia ² especially after cardiac surgery. ³ The role of anesthetic agents in adverse neurobehavioral disturbances is being increasingly recognized. ⁴ Central anticholinergic syndrome (CAS) ⁵ is a well-recognized, though uncommon ⁶ cause of acute psychosis that is a specific anesthetic related phenomenon. CAS is a broad classification of symptoms and signs that generally include symptoms of psychosis. It is associated with a variety of behaviors including agitation, seizures, restlessness, hallucinations, disorientation or signs of depression such as stupor, coma and respiratory depression. Its occurrence has diminished since the major tranquilizers (phenothiazines, butyrophenones) have fallen into disfavor as means of preventing vomiting or for inducing sedation. It may still occur however, and has been induced by opiates, benzodiazepines (valium like drugs); ketamine, etomidate, propofol (intravenous anesthetics); nitrous oxide and halogenated inhalation anesthetics (inhaled anesthetics) as well as by H2-blocking agents such as cimetidine used for treating gastric ulcers. ⁷ The differential diagnosis for a postoperative patient presenting with abnormal neurological signs and symptoms should include CAS after the exclusion of other potential causes. ⁸

References

1. Rupreht J. The central muscarinic transmission during anaesthesia and recovery–the central anticholinergic syndrome. Anaesthesiol Reanim. 1991;16(4):250-8.
2. Abdullah MS1, Al-Waili NS, Baban NK, Butler GJ, Sultan L. Postsurgical psychosis: case report and review of literature. Adv Ther. 2006 Mar-Apr;23(2):325-31.
3. Dieter Naber, Monika Bullinger Neuroendocrine and psychological variables relating to post-operative psychosis after open-heart surgery Original Research Article Psychoneuroendocrinology, Volume 10, Issue 3, 1985, Pages 315-324
4. Anticipating and managing postoperative delirium and cognitive decline in adults. BMJ 2011; 343 doi: http://dx.doi.org/10.1136/bmj.d4331 (Published 20 July 2011)
5. Rupreht J. The central muscarinic transmission during anaesthesia and recovery–the central anticholinergic syndrome. Anaesthesiol Reanim. 1991;16(4):250-8.
6. Senne I, Zourelidis C, Irnich D, Kurz M, Hummel T, Zwissler B. [Central anticholinergic syndrome and apnea after general anaesthesia. A rare manifestation of the central anticholinergic syndrome]. Anaesthesist. 2003 Jul;52(7):608-11.
7. Schneck HJ1, Rupreht J. Central anticholinergic syndrome (CAS) in anesthesia and intensive care. Acta Anaesthesiol Belg. 1989;40(3):219-28.
8. Moos DD. Central anticholinergic syndrome: a case report. J Perianesth Nurs. 2007 Oct;22(5):309-21.