Oral medications in NBM patients undergoing radiographic contrast

• Fasting should not be systematic before a radiological examination with injection of iodinated contrast media(ICM)
• Fasting may be useful in some rare instances to visualise the gallbladder, help visualise the gut wall or its viscinity, facilitate specific actions requiring sedation or specific anaesthesia.

Recommendations:

Non diabetic medications

• Take all non diabetic medications as directed. No other medications should be stopped for patients received radiographic contrast media. Unless specifically instructed by their physician, patients should continue taking their regular prescribed medications for diabetes (Insulin, etc), cardiac, and other medical condition(1)

In diabetic patients

• Metformin is not a risk factor for developing contrast induced nephorpathy (CIN) and the injection of CM is not contraindicated in patients taking it.
• However, serious complications (lactic acidosis) may rarely occur in patients taking metformin who subsequently develop AKI
• Metformin should be discontinued on the day of the proposed CM administration, withheld for the subsequent 48 hours and recommenced after renal function has been re-evaluated and found to have returned to baseline 
• The European Society of Urogenital Radiology adopts a conservative approach and recommends holding metformin at the time of injection in patients with normal SCr and 48 hours prior to injection for elective studies in patients with abnormal renal function
• It is generally unnecessary to stop metformin 48 hours prior to contrast injection but special care should be taken in patients with severe or acute renal dysfunction.
• In patients with eGFR < 45 mL/min: Metformin should be stopped at the time of contrast injection and should not be restarted for at least 48 hours and only then if renal function remains stable (less than 25% increase compared to baseline creatinine).
• Certain authors consider it unnecessary to discontinue metformin or recheck renal function following the use of normal volumes (<100mL) of contrast media in patients with normal baseline renal function 

References:
1. http://radres.ucsd.edu/Policies/Contrast%20Media%20Guidelines%20UPDATED%2018Jun2014.pdf
2. http://www.sfrnet.org/data/upload/files/a7e7222e420ac736c1256b6c0044cb07/contrast%20media%20prescribing%20fasting.pdf
3. http://www.car.ca/uploads/standards%20guidelines/20110617_en_prevention_cin.pdf

Pre-operative oral medications in nil by mouth(NBM) patient undergoing surgical procedure

Consideration for NBM:

• Pre or post surgery
• When the bowel is non-functional e.g. gastric outlet obstruction
• The patient is unable to swallow safely e.g. after a stroke, head injury, myasthenia gravis or reduced level of consciousness.
• Nausea or vomiting may also inhibit the intake of fluids, nutrition and oral medicines

Why NBM?

Patients are at risk of aspirating their stomach contents during general anaesthesia. Therefore minimum fasting periods for scheduled surgery are:

• 6 Hours for solid food, infant formula or milk
• 4 Hours for breast milk
• 2 Hours for water, dilute squash or tea/coffee with a small amount of milk
• As water leaves the stomach within 2 hours of ingestion, medicines can be given up to two hours before surgery with water.

Oral medications
To continue or omit prior to surgery? It may be appropriate to give the oral medicine. Consider:

1. Medicines that should be continued throughout the peri-operative period to prevent relapse of the treated condition or to avoid the effects of drug withdrawal.
2. Medicines that should be withheld before surgery to reduce the risks that they may impose upon the procedure.

Medications to CONTINUE

Medications	Exception
All cardiac or BP drugs (eg anti-anginal, anti-arrhythmia)	Except ACE inhibitors, ARB and diuretics (refer below) Amiodarone can be safely omitted for a few days as it has a very long half-life. Alpha blocker to continue if indicated for BP control. If for urinary retention and patient is catheterized, may be withheld if patient at risk of hypotension.
All epilepsy or Parkinsons drug
All asthma drugs/inhalers
All tablets which reduce gastric pH eg ranitidine, omeprazole, pantoprazole
All thyroid drugs
All major and minor tranquilisers eg benzodiazepines, antidepressants and nicotine patches
All steroids including inhalers
All immunosuppressants and cancer drugs
All analgesics (eg opiods)	Except NSAIDS

Medications to OMIT

Lithium	Omit due to risk of toxicity
NSAIDS	Omit unless prescribe as premed EXCEPTION: Cox-2 selective inhibitor (to continue) Non selective NSAIDs Possible increased risk of bleeding. If the risks of postoperative bleeding are high or where the consequences of even minor bleeding are significant e.g. retinal, stop NSAIDs 3 days before surgery to allow platelet function to recover.

Clozapine	Stopped 24 hours before surgery.
Glucosamine	Glucosamine may affect blood glucose control. Glucosamine and chondroitin may have an anticoagulant effect and should therefore be discontinued two weeks prior to surgery.

Aspirin, clopidogrel, dipyridamole, warfarin

Omit except for patients with coronary artery stent upon discussion with GP Should be stopped when risk of preoperative bleeding are high or where consequences of even minor bleeding are significant, balanced against risk of precipitating thromboembolic complications if these are stopped. To stopped generally 7 days before surgery to allow recovery of adequate platelet function  Warfarin ideally stop 5 days before surgery to allow INR to drop below 1.5. Epidural analgesia will require INR ≤1.5

MIXED review:

Medications	Consideration
ACE inhibitors/ ARB	May drop blood pressure during anaesthetic.  To withhold unless requested(1) ACE I  To continue therapy and inform the anaesthetist who may request the preop dose to be omitted(2) ARB For hypertensive patient’s likely to have an epidural anaesthetic, withhold on the morning of surgery. For congestive heart failure and/or history of myocardial infarction patients, continue therapy and inform the anaesthetist(2)
All diuretics	Depends on clinical judgement(1) Thiazide and loop diuretics need not be omitted. Any electrolyte imbalance should be corrected before surgery. Withhold if patient dehydrated but seek advice if patient has cardiac failure. Omit potassium-sparing diuretics on the morning of surgery as reduced kidney perfusion in the immediate post-operative period may predispose to hyperkalaemia.

Others

Drugs not essential in short term eg vitamins, iron, laxatives, osteoporosis treatment, liquid antacids, HRT, herbal can be omitted(1) Counteract arguments(2): COC should be discontinued 4-6 weeks before major elective surgery and all surgery to the legs to reduce the risk of thromboembolism. Alternative contraception e.g. progestogen only pill. Iron supplementations, continue unless bowel surgery then discontinue 7 days pre-operatively. Vitamins and mineral supplements can be continued. Herbal should be discontinued HRT Preferably discontinue 4 weeks prior to major surgery or where there is a high risk of a thromboembolic event. If not, HRT may be continued peri-operatively but thromboprophylaxis is recommended.

Kindly refer to link (2) for further information.

References:

1.http://www.uhs.nhs.uk/Media/subtideal/Doctors/SaferPrescribingWorkbook/Section4Appendix2-Peri-operativedrugs.pdf

2 http://www.worcsacute.nhs.uk/EasysiteWeb/getresource.axd?AssetID=11296

Comparison: Pediatric Sedatives

 

 

References:

1. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4040023/
2. NICE clinical guideline 112 – Sedation in children and young people
3. THE SOCIETY FOR PEDIATRIC SEDATION : SEDATION PROVIDER COURSE
   SYLLABUS

Analgesia: Pregnancy, breastfeeding, paediatric

Analgesia

Dose (adult)	Paediatric	Route	Pregnancy	Breastfeeding
Ibuprofen
200-400mg 4-8H	5-10mg/kg 4-8H (for age specific dose, refer to BNF for Children)	Oral	·                     C/ D (≥30 weeks gestation) ·                     Not recommended unless potential benefits outweigh possible hazards.b	·  Contraindicated (Canadian prescribing information). ·  Based on limited data, excreted into breast milk, providing a relative infant dose of 0.06 to 0.6% of the weight adjusted maternal dose. ·  Adverse events have not been reported in nursing infants. ·  Not recommended unless expected benefits  outweigh potential risk.b
Diclofenac Sodium
75-150 mg/day in 2-3 divided doses. Maintenance: 75 mg/daily (or 100mg/daily)b in over 2-3 divided doses. Max duration: 2 days.	Child 2–18 years:  0.3–1 mg/kg Once or twice daily for max. 2 days (max. 150 mg daily)	IM	·                     C/ D (≥30 weeks gestation) ·                     Should not be usedb	·  Low concentrations can be found in breast milk. Contraindicated in Canadian labelling. ·  Not recommended. Following oral doses of 50mg administered every 8 hours, the active substance, diclofenac passes into breast milk.b
Depending on the size of painful site, apply 2-4gm TDS-QIDb	Adolescent ≥16 years: Refer to adult dosing.	Gel	·                     B (topical gel 3%) / C (topical gel 1%) ·                     Since no experience has been acquired, it is not recommended.b	·  It is not known if it is excreted in breast milk.
50mg 8-12H4	Child 6 months–18 years 0.3–1 mg/kg  (max.50 mg) 3 times daily3 0.5-1mg/kg 8-12H4	Oral	·                     C/ D (≥30 weeks gestation) ·                     During late pregnancy should be avoidedb	·  Low concentrations can be found in breast milk. ·  Contraindicated in Canadian labelling. ·  Not recommendedb
Mefenamic Acid
500mg 8H4	Child 12–18 years 500 mg 3 times daily3 10mg/kg 8H4	Oral	·                     C	·  Trace amounts may be present in breast milk. ·  Contraindicated in Canadian labelling.
·                     Aspirin
300-600mg 4-6H4 300-900mg 4-8H, up to maximum of 12 tablets  daily (per24 hours)b	10-15mg/kg 4-6H4	Oral	·                     Cross placenta & enter fetal circulation. Adverse effects reported in fetus and mother. In general, low doses during pregnancy have not been shown to cause fetal harm, but discontinuing therapy prior to delivery is recommended. ·                     Don’t take during last 3 months of pregnancy unless ordered by doctor.b	·  Low amounts can be found in breast milk. Peak levels in breast milk are reported (9 hours after a dose). ·  Occasional doses of aspirin compatible with breast-feeding, but avoid long-term therapy & consider monitoring infant for adverse effects (WHO, 2002). ·  Other sources suggest avoid due to theoretical risk of Reye’s syndrome (Bar-Oz,2003; Spigset,2000). ·  Pass into breast milk. Not been reported to cause problems in nursing babies, possible that problems may occur if large amounts are taken regularly, as for arthritis.b

^bManufacturer’s recommendation

*for other indication please refer to other guideline

**Because of the known effects of NSAIDs on the foetal cardiovascular system (closure of ductus arteriosus), use during late pregnancy should be avoided.

References

1. http://www.mims.com/malaysia

2.https://www.drugs.com/

3. BNF for Children 2014–2015

4. Drug Doses, Frank Shann, 16^th Edition 2014

5. Lexicomp