Use of diclofenac sodium suppositories in post operative pain management

Results: Mean age of the population was 48.15yrs (SD=15.91), 51.3% being males and 70.7% had received diclofenac sodium suppository post-operatively. Of them 92.5% were not informed prior to administration of the suppository. Majority were not questioned about peptic ulcers (50.9%), bleeding disorders (72.6%), allergy for non steroidal anti-inflammatory drugs –NSAIDs (50.0%) and renal impairment (62.2%), which are contraindications for the drug. Among those given diclofenac, 12.3% had asthma, 2.8% coagulation defects, 17% ischaemic heart disease, 11.3% peptic ulcer, 31.1% hypertension, 1.9% allergy to NSAIDs, 0.9% heart failure, 5.75% renal impairment which are contraindications for use of NSAIDs and 12.3% were elderly.


Introduction
The goal for postoperative pain management is to reduce or eliminate pain and discomfort with minimum of side effects as cheaply as possible 1 .NSAIDs are prescribed commonly in mild to moderate pain 2 .Diclofenac is one such NSAID which has been shown to have analgesic effect in several situations, such as post operative pain after tonsillectomy 3 , tooth extraction 4 and hip joint surgery 5 .
In the pre operative period information should be provided about intra and post operative analgesia, techniques of sensitive nature such as the insertion of analgesic suppository 6 and check for contraindications to NSAIDs and local anaesthetic techniques 7 .
The relative contraindications for the use of the NSAIDs are 8 • Impaired hepatic function, diabetes, bleeding or coagulation disorders, vascular disorders The aim of this audit was to assess whether, patients were informed of diclofenac sodium suppository administration, and whether they were questioned about contraindications and cautions for its use and to evaluate the percentage of patients who had the contraindicated disease states.

Methods
The audit comprised a descriptive cross sectional study, which was carried out in all general surgical wards in the National Hospital of Sri Lanka.Study population was 150 patients who were in post operative day one or two, and who gave written consent to participate.Patients who were not able to communicate, mentally subnormal and patients who were not in post operative day one or two were excluded.
Data was extracted from bed head tickets and an interviewer administered questionnaire was also used.The audit was approved by the Ethics Review Committees of the National Hospital of Sri Lanka and the Faculty of Medicine, Colombo.

Results
The study population comprised of 150 patients, of mean age of 48.15yrs (SD=15.91).Socio-demographic and basic clinical information of the study population are shown in Table 1.Among 150 patients 70.7% (n=106) received diclofenac sodium suppository post operatively.

Figure 1: Frequency of administration of diclofenac sodium suppository for post operative pain
Among patients who received the drug (n=106) the type of surgery and the type of anaesthesia are described in (Table 2 and 3).More than 50% of patients who received diclofenac sodium were not questioned about a history of peptic ulcers, bleeding disorder, allergy for NSAIDs and renal impairment which are contraindications for the drug.(Figure 3) A considerable percentage of patients had relative contraindications.Table 4 shows the presence of physician diagnosed diseases or conditions which are contraindications or cautions for diclofenac sodium among the patients who were given that drug for post operative pain relief.

Discussion
As the audit population was selected from all general surgical wards it represents the patients who are undergoing general surgeries in National Hospital of Sri Lanka.In the present audit majority were given diclofenac sodium suppository as immediate post operative analgesia which indicates that it is a commonly used drug for post operative pain relief.It is noted that rectal administration of drugs is relatively unpopular in the UK 9 .
The present study revealed that obtaining consent was practiced only in 7.5% of patients and about 92.5% were not informed prior to administration of the drug.This suggests inadequate attention for post operative pain management in the pre operative assessment of the patient.A range of analgesic options may be available for a particular type of surgery out of which a suitable regime can be selected considering the patients preference 2 .Diclofenac suppository has been used in 5.7% (n=6) with renal impairment while 62.2% (n=66) were not questioned about a history of renal failure prior to administration.In a double blind study it was shown that, all patients receiving diclofenac after oesophago-gastrectomy had significantly reduced urine out put and potassium excretion with tendency to hyperkalaemia 10 .It was also used in 12.3% (n=13) of elderly patients, 31.1% (n=33) patients with hypertension, 17% (n=18) ischaemic heart disease patients and 0.9% (n=1) patients with heart failure.As elderly people are most likely to have multiple organ dysfunction there is a greater potential for interference between NSAIDs and other drugs.NSAIDs may interfere with pharmacological control of hypertension and heart failure.The action of drugs such as frusemide depends on prostaglandin and the unbound concentrations of some NSAIDs are high in the elderly 11 .
It was given in 11.3% (n=12) with peptic ulcer while 50.9% were not questioned about the disease.When comparing with other studies regarding NSAIDS use and peptic ulcer found that when indomethacin 50 mg was given three times daily all volunteers had endoscopic evidence of mucosal damage in both stomach and duodenum after 24 hrs 12 .Another study of NSAIDs and peptic ulcer disease found that after five days of administration of ketorolac (90mg) 'invasive' antral ulcers were found in 80% of subjects 13 .

Conclusions
Diclofenac sodium suppository is used in majority (92.5 %) of patients without consent and without checking contraindications for the drug.A considerable (eg: peptic ulcer 11.3%, hypertension 31.1%)percentage of patients with contraindications or cautions have been given diclofenac.

Recommendations
There is a need for a guideline prescription of diclofenac sodium suppositories in the post operative period.It is also important to educate doctors and nurses of its contraindications and the importance of obtaining consent.

Figure 2 :
Figure 2: consent obtained prior to administration of the drug

Table 1 :
Socio-demographic and clinical data

Table 2 :
Type of surgery undergone by patient who had diclofenac sodium suppository postoperatively.

Table 3 :
Administration of diclofenac according to the type of anaesthesia

Table 4 :
Association between type of anaesthesia and administration of diclofenac sodium

Table 4 :
Presence of disease among patients who