Survey of Post-Operative Prescribing Preferences in the United Kingdom among Anaesthesia professionals*

 

Emily Pallister produces a survey asking which medications are most widely available to anaesthetists for post-operative prescribing, and if others are increasing in popularity and accessibility 

 

Summary

Drug prescribing for post-operative patients by anaesthetists can vary greatly, and is influenced by factors including personal preference, experiences, type or severity of procedure, local guidelines and formulary. Sharing of such knowledge can be important in achieving good awareness, thereby ensuring better clinical outcomes. A survey was designed online and distributed via email to analyse post-operative prescribing preferences of UK Anaesthetists. A standardised scenario of an ASA 1 patient for differing severity of procedure was used, and participants were asked to choose medications from a given list, or indicate ‘other’ with a free text explanation. Demographic information and survey results were collected for three hundred and thirty participants. For regular analgesia, paracetamol was by far the most popular. Morphine patient controlled analgesia was chosen for major and major+ surgeries, whilst ibuprofen was popular for day surgery and intermediate procedures. Oral morphine preparations were popular as an ‘as required’ (PRN) prescription alongside codeine for more minor procedures. Adjuvant medications were more often prescribed PRN rather than regular – at most only 35 per cent prescribe regular adjuvants in the form of anti-emetics. Ondansetron, granisetron and cyclizine were most prevalent. Naloxone was the second most popular PRN medication for major and major+ surgeries. Free text ‘other’ suggestions included tramadol, oxycodone and OxyContinâ. This survey produced interesting results which portrayed a variability in practice regarding post-operative prescription. A further survey involving more participants may be needed to ascertain a nationwide practice and support for a standardised approach in post-operative prescription.

 

Introduction

One of the key responsibilities in the role of the anaesthetist is consideration of analgesic techniques and provision of prescriptions for post-operative analgesia, anti-emetics and adjuvants in the recovery room, post anaesthetic care unit (PACU) and on the post-operative ward. Prescribing post-operative medications can vary widely depending on Anaesthetist preference, local guidelines and formulary. Our own experiences, patient satisfaction and knowledge of side effect profile can also shape our preferences. The medication prescribed, the routes of administration and regular or as required (PRN) use can even differ between similar patients having the same procedure.

Although much is known about drug pharmacology, little literature exists about the prescribing preferences of UK Anaesthetists. Surveys that have been published focus on post-craniotomy prescribing in UK neurosurgical centres. Roberts [1] determined that codeine was the most popular analgesic (78 per cent of centres, 52 per cent as regular prescription) compared to morphine (13 per cent), and where balanced analgesia was offered, paracetamol was used by 100 per cent of centres, with 30 per cent also providing diclofenac. Kotak et al [2] similarly demonstrated that paracetamol (84 per cent of units) and codeine (70 per cent) were the most popular analgesics for post-craniotomy patients. Fifty-two percent used non-steroidal anti-inflammatory drugs (NSAIDs) PRN, but rarely as a regular prescription (19 per cent). Cyclizine was the most popular anti-emetic (45 per cent).

Literature searches using PubMed on this topic highlighted publication of practitioner and patient surveys of post-operative pain and prescribing undertaken in the Netherlands and in France. Unfortunately, English versions of these publications could not be obtained for full analysis, and information from abstracts was of limited relevance to this survey.

It is thought that collection and sharing of knowledge can be used for improving the patient satisfaction and experience in the post-operative period. Also it promotes teaching and discussion amongst the anaesthetic community. For this purpose, an online survey was designed and distributed to the anaesthetic departments of hospitals nationwide via email. The results will indicate which medications are most widely available, and if others are increasing in popularity and accessibility.

 

Methods

An online survey was produced using SurveyMonkey® comprising seven questions. A link to the survey was included in an email sent to the anaesthetic department secretaries of hospitals across the UK. The survey was open for seven months prior to analysis.

Initial questions were used to collect basic demographic data about the respondent i.e. grade of Anaesthetist, country of residence (England, Scotland, Wales or Northern Ireland) and type of hospital (Teaching hospital or District General).

Subsequent questions posed the hypothetical scenario of an ASA 1 patient for elective surgery. In the absence of regional or neuraxial techniques, the respondents were asked to indicate which of the listed analgesia and adjuvants they would prescribe on a regular and PRN basis for surgeries of Day Surgery/Minor, Intermediate, Major and Major+ class. Free text boxes were provided for further comments.

 

The list of analgesia given was as follows:

• Paracetamol
• Diclofenac
• Ibuprofen
• Codeine
• IV morphine
• Morphine PCA
• SC/IM morphine
• Intranasal fentanyl
• Gabapentin
• Pregabalin
• Other

 

The list of ‘adjuvants’ included:

• Senna
• Lactulose
• Ondansetron/Granisetron
• Prochlorperazine
• Cyclizine
• Metoclopramide
• Other anti-emetic
• Naloxone
• Chlorphenamine
• None of the above

 

Feedback was taken from the initial respondents necessitating the survey to be modified. In particular, the wording of questions asking for ‘routine use’ caused confusion and so were quickly changed to ‘regular use’. Information in the free text spaces was reviewed and any answers altered accordingly in line with the respondent’s wishes. Similarly, one question was highlighted as requiring an answer, even when the respondent didn’t prescribe any of the medications listed. Again, where this had been indicated as free text, the submitted responses were reviewed and discarded as appropriate. The resulting frequency tables and percentages were adjusted accordingly. The results were analysed using simple statistical methods.

 

Results

Four hundred and fifty anaesthetists answered the survey, 317 of which completed the survey. Fifty-five percent of respondents worked in a District General Hospital, the remaining 45 per cent in a Teaching Hospital. Most respondents worked in England (313; 69.6 per cent), followed by Scotland (92; 20.4 per cent), Wales (37; 8.2 per cent) and Northern Ireland (8; 1.8 per cent).

The clear majority of respondents were consultants or post CCT Fellows (64.9 per cent). There was an even spread from training grades of anaesthetists (7.3 per cent-8.7 per cent each), with 3.5 per cent representing Clinical Fellows. Participants answering “Other’ were Physicians Associates and CT3 trainees. One response correctly identified the ST5 grade as ‘Higher’ instead of ‘Intermediate’ training. Although it was too late to alter the survey, the responses were counted and amended as necessary.

Subsequent questions posed the hypothetical question of an ASA 1 patient scheduled for theatre. Respondents were asked to indicate from the given list of analgesia and adjuvants, which they would prescribe on a regular and PRN basis.

“In a situation that you are anaesthetising for procedures of the following duration, which would you prescribe as REGULAR /PRN analgesia/adjuvants? Assume that your patient is young, fit with no comorbidities and that you have not undertaken regional or neuraxial blockade. (Select all that apply)”

 

Regular Analgesia

Three hundred and thirty participants completed this portion of the survey. The popularity of different analgesic agents was determined by the severity of surgery. Paracetamol proved most popular for all durations of surgery – it was chosen at least once by 99 per cent of respondents. The use of paracetamol varied only slightly across the surgical severity – 87 per cent chose it for day surgery; 97 per cent for major surgeries.

 

 

For Day Surgery and Minor surgery classes ibuprofen, codeine and diclofenac were next popular. This is in keeping with the WHO pain ladder [3]. Ibuprofen proved the most popular NSAID, chosen by 84 per cent of respondents at least once, compared to 24 per cent who prescribe diclofenac. Of those using diclofenac, its use was more popular for Intermediate, Major or Major+ surgeries whereas ibuprofen was popular for Day Surgery or Intermediate classes.

However, for Major and Major+ surgeries morphine PCAs were second most popular before ibuprofen (prescribed by 75 per cent of respondents). This is more in keeping with the anticipated pain levels of the types of surgery involved.

 

 

 

‘As Required’ (PRN) Analgesia

In general, the number of PRN prescriptions was much lower than for regular analgesia. Despite this, the number of participants choosing codeine or oral morphine was higher PRN than for regular prescription. Oral morphine proved most popular PRN, apart from Day Surgery/Minor procedures where codeine was prevalent. Oral morphine was three times more likely to be prescribed PRN than regularly (244 of total respondents PRN; 80 regularly), with only a small difference between the usage for codeine (183 respondents choosing PRN; 140 choosing regular).

For Major and Major+ surgeries oral morphine and IV morphine in the form of boluses and PCAs were popular. IV morphine can be administered by Recovery nurses in many units, which could represent its popularity on a PRN prescription (128 respondents, 39 per cent).

In comparison, the use of paracetamol was much less – only 16% of respondents indicated PRN use, of which almost all was for day surgery.

 

 

‘Other’ analgesia

Thirty-four respondents indicated that they would choose ‘other’ medications to prescribe on a regular basis, and 51 on a PRN basis (15 per cent of respondents). Four respondents stated that they would use regional or epidural techniques on a regular basis for specified surgeries. Although this is valid, it contravenes the scenario. Tramadol PRN was a popular suggestion however not to the same extent of codeine. Newer opioids such as oxycodone and OxyContin® were also suggested for regular use, and oxycodone or OxyNorm® for predominantly PRN use. Participants who stated ‘oxycodone’ in the free text box did not indicate preparation and hence OxyContin® and OxyNorm® have been reported as separate entities. One respondent indicated the use of lignocaine for regular use. Due to limitations of the survey it is not specified if this is for subcutaneous or regional use, or for intravenous use. Other drugs in the class of NSAID and Cyclo-oxygenase (COX) inhibitors that were suggested included naproxen, parecoxib and nefopam. Fentanyl was suggested for use in a variety of different preparations – most popular for IV use PRN, but also as a patch for regular or PRN use, and as a PCA for regular or PRN use.

 

 

Regular Adjuvants

The number of regular adjuvant prescriptions are generally low with at most 116 respondents prescribing a regular anti-emetic (ondansetron or granisetron). For shorter duration of surgeries no regular adjuvants were prescribed, indicated by the ‘None of the above’ option (87 respondents, 26 per cent). For Major or Major+ surgery classes ondansetron/granisetron were the most popular adjuvant. Laxatives senna (14-15 per cent) and lactulose (17-20 per cent) were prescribed primarily for Major-Major+ surgeries. For Day Surgery and Moderate surgeries, the regular prescriptions were more likely to be anti-emetics.

 

 

‘As Required’ (PRN) Adjuvants

Three hundred and twelve participants completed this part of the survey. The use of adjuvants were much more popular on a PRN basis rather than regular basis. Primarily PRN adjuvants were most likely to be anti-emetics. Ondansetron or granisetron (88 per cent), and cyclizine (82 per cent)were the most popular PRN prescriptions for all durations of surgery, with prochlorperazine (21 per cent) proving the third most popular anti-emetic. The most popular adjuvant that is not an anti-emetic is naloxone (31 per cent). Naloxone was more likely to be prescribed in Major and Major+ surgeries in line with increased opioid use for these cases. It was unlikely that ‘None’ of the adjuvants were prescribed (<1 per cent), in contrast to regular prescriptions.

 

‘Other’ Adjuvants

Notably fewer respondents indicated that they would prescribe other adjuvants than those listed. Where suggestions were given, droperidol was the most popular (5 choosing for regular use, 4 for PRN). Others included antacids such as ranitidine (1 prescriber for regular use) and omeprazole (2 prescribers for regular use) which could represent gastric protection with non-steroidal use. In addition, other laxatives such as docusate (1 regular use, 2 PRN), picosulfate (1 regular use), movicol (4 for regular use) and laxido might be prescribed (3 for regular use, 1 PRN). Haloperidol was offered by one respondent PRN, and hyoscine by two PRN.

 

Discussion

The survey yielded many interesting results. In the absence of neuraxial or regional techniques the predicted pain score given by patients post-operatively is in keeping with the findings of this survey. Namely, the widespread use of paracetamol, NSAIDs and weak opiates for the less severe procedures, and use of IV opiates for the more severe. Similarly, the use of adjuvants on a mainly PRN basis. This is the first time that current prescribing preferences of UK Anaesthetists have been formally confirmed as similar work does not exist on literature search.

Paracetamol was understandably and predictably the most commonly prescribed analgesic, particularly on a regular basis for all forms of surgery. Its popularity is likely thanks to its widespread accessibility, availability as an IV preparation, good oral bioavailability and good safety profile.

Ibuprofen is still commonly prescribed as a regular medication in day surgical cases but its use diminishes in Major and Major+ surgeries, particularly PRN. Like paracetamol this is probably due to the widespread use as a regular analgesic, therefore it is not required PRN. However, high risk patients undergoing major surgery would be at increased risk of acute kidney injury, therefore it is understandable that NSAIDs are avoided, which could compound this effect.

Codeine was the most popular opioid for Minor procedures on a regular prescription. Both codeine and oral morphine (prescribed widely for Major surgeries) proved more popular on a PRN rather than regular basis. In many Day Surgery units oral morphine preparations cannot be dispensed for discharge, and their use is often not indicated for the procedures being undertaken. Codeine however is more widely available for ‘take home’ prescriptions, either alone or combined with paracetamol, which could explain its popularity both regular and PRN to satisfy the WHO pain ladder. However, variations in individual’s abilities to metabolise codeine to its morphine metabolites, and tendency to cause constipation can preclude its use for more major surgeries. Where pain is more likely to be problematic with Major and Major+ surgeries, oral morphine can prove extremely helpful for breakthrough pain PRN or providing some stronger opiate cover in the immediate post-operative period.

Morphine PCAs on regular prescription and naloxone PRN are popular for Major and Major+ surgeries. In the absence of neuraxial, epidural or regional techniques, as permeated by the question, it is logical that a PCA would be chosen for analgesia for procedures of greatest severity. It is generally safe for ward use and does not require additional monitoring. However, unless an epidural was sited as the primary form of analgesia, a PCA would be prescribed regularly and not PRN as corroborated by the survey results, although this would depend on local drug cards. Many Trusts have a protocol for the prescription of morphine PCA that indicates the co-prescription of oxygen and naloxone in case of emergency.

In comparison to the PCA, intravenous morphine may only be given in monitored situations. The survey demonstrated its usage PRN, reflecting the administration in HDU or Recovery. Newer opioids such as oxycodone are increasing in popularity, however oral morphine remained widely used on a PRN basis.

Of the anti-emetics, ondansetron/granisetron were by far the most popular. Although they were the most commonly prescribed regular adjuvant drugs, the frequency of their use was actually small in number. It is evidently unusual to prescribe anti-emetics regularly, although this might change if the patient had a history of severe post-operative nausea and vomiting. However, their few side effects and generally good safety profile is likely to favour them in comparison to other anti-emetics. Anti-emetics were prescribed particularly for PRN use, and it was on these terms that the use of ondansetron and cyclizine were similar, particularly for Major and Major+ surgeries. Prochlorperazine also demonstrated that it was utilised as a third-choice anti-emetic for this use.

The survey showed that Anaesthetists in the UK would consider the prescription of laxatives for patients undergoing Major+ surgery who are likely to be receiving a high dose of opiates. These medications prove effective and important in the avoidance of unpleasant constipation whilst patients are recovering from their surgery.

The findings of this survey are likely in keeping with one’s own personal prescribing preferences. Any differences can prompt reflection and education with Anaesthetists in training and amongst peers. Similar work if undertaken in different countries could permit greater understanding and education with our international compatriots.

The survey was limited by the number of responses received, and the number of Anaesthetists that completed the survey to the end. In future, similar work is proposed with repeated emails to encourage greater participation. Affiliation with training bodies such as colleges and associations would likely improve this, as would use of social media.

In conclusion, this survey permits an insight in to the current prescribing preferences of UK Anaesthetists, and in doing so is the first body of work of its kind.

 

Acknowledgments: None.

Competing Interests: No external funding and no competing interests declared.

Authors’ Contributions and Authorship:

E.P Survey design, data collection and analysis and writing of first draft of paper.

M.P Survey conception, drafting and editing.

A.S Survey conception, drafting and approval of final publishable version.

 

References

1. Roberts, G.C. Post-craniotomy analgesia: current practices in British neurosurgical centres – a survey of post-craniotomy analgesic practices. Eur J Anaesthesiol 2005; 22: 328-332
2. Kotak D, Cheserem B, Solth A. A survey of post-craniotomy analgesia in British neurosurgical centres: time for perceptions and prescribing to change?. British Journal of Neurosurgery 2009; 23 (5): 538-42.
3. World Health Organisation. WHO Cancer Pain relief: with a guide to opioid availability, 2^nd Edition. Geneva, 1996

 

Survey of Post-Operative Prescribing Preferences in the United Kingdom among Anaesthesia professionals*

1. Pallister, ¹ A. Sajayan² and M. Patteril³

^{1, 3}University Hospitals of Coventry and Warwickshire, Clifford Bridge Road, Coventry, CV2 2DX, United Kingdom. mathew.patteril@uhcw.nhs.uk

²Good Hope Hospital, Rectory Road, Sutton Coldfield, B75 7RR, United Kingdom. sajayan@gmail.com

Correspondence to: Dr Emily Pallister (emily.pallister@nhs.net)

*Poster of survey displayed at AAGBI GAT conference, 15^th June – 17^th June 2016 at Nottingham Conference Centre and published in Anaesthesia supplement:

Pallister, E, A Sajayan, and M Patteril. 2016. “Survey of Postoperative Prescribing Preferences in the UK.” Anaesthesia 71: 32. doi:http://dx.doi.org/10.1111/anae.13519

 

 

Keywords

Analgesics, Antiemetics, Drug Prescriptions, Pain Management
Surveys and Questionnaires, United Kingdom