Once Daily Gentamicin Antibiotic Guidelines

Antibiotic Guidelines: Once Daily Gentamicin

Reference Number 144TD(C)25(H2) Version 5.1 Issue Date: 07/02/2020 of 13 It is your responsibil ity to check on the intranet that this printed copy is the latest version

Once Daily Gentamicin Antibiotic Guidelines

Lead Author: Antibiotic Steering Committee

Additional author(s) Alex Peel, Consultant Microbiologist

Sue Wei Chong, Antimicrobial Pharmacist

Division/ Department:: DCSS & Tertiary Medicine

Applies to: Salford Royal Care Organisation

Date approved: 20/01/2020

Expiry date: January 2023

Contents

Contents

Overview ...................................................................................................................................... 2

Scope & Associated Documents ................................................................................................ 2

Background.................................................................................................................................. 3

What is new in this version? ....................................................................................................... 3

Guideline ...................................................................................................................................... 3

1. Important Principles ............................................................................................................ 3

2. Remit of this guideline ........................................................................................................ 4

3. Dose Calculation................................................................................................................. 4

Table 1 – Gentamicin dosing table for CrCl >30mls/min (based upon 5mg/kg drug dosing

weight)................................................................................................................................. 7

Table 2 – Gentamicin dosing table for CrCl<30ml/min and/or >75 years and/or frail or haemodynamically compromised patients (e.g. dehydration/shock) ............................... 8

Roles and responsibilities ........................................................................................................... 9

Monitoring document effectiveness............................................................................................ 9

Abbreviations and definitions ...................................................................................................... 9

References ................................................................................................................................ 10

Document Control Information.................................................................................................. 11

Equality Impact Assessment (EqIA) screening tool ................................................................ 12

Group arrangements:

Salford Royal NHS Foundation Trust (SRFT)

Pennine Acute Hospitals NHS Trust (PAT)



Overview

This guideline gives recommendations for once daily gentamicin dosing

The tables are a guide to initial dosing but individual patient assessment involving discussion with pharmacy +/- microbiology may be required This guideline should not be used for:

- Endocarditis

- Pregnancy

- Cystic fibrosis

- Major burns (>20%)

- Ascites

- Renal dialysis or for patients with end stage renal disease

Gentamicin should be used with extreme caution in patients with acute kidney injury (AKI), and only then after being discussed with a senior doctor (ST3 or above) If you have any concerns about the content of this document please contact the author or

advise the Document Control Administrator.

Scope & Associated Documents This policy applies to all clinical staff involved in the prescribing of antimicrobials.

This document provides treatment guidelines for the most common situations in which antibiotic treatment is required. The products and regimens listed here have been selected

by the Trust's Medicines Management Group on the basis of published evidence. Doses assume a weight of 60-80kg with normal renal and hepatic function. Adjustments may be needed for the treatment of some patients.

This document provides treatment guidelines for the appropriate use of antibiotics. The recommendations that follow are for empirical therapy and do not cover all clinical

circumstances. Alternative antimicrobial therapy may be needed in up to 20% of cases. Alternative recommendations will be made by the microbiologist in consultation with the clinical team.

This document refers to the treatment of adult patients (unless otherwise stated). Refer to up to date BNF/SPC for information on interactions, side effects, cautions and contraindications for individual drugs.



Associated Documents

144TD(C)25(A5) - Issue No 3.1 - Antimicrobial Stewardship Policy

http://intranet.srht.nhs.uk/policies-resources/trust-policy-documents/topics-

prescriptions/antibiotic/antibiotic-prescribing-principles/144tdc25a5/

163TD(C)(33) – Issue No. 14 - Medicines Policy

http://intranet.srht.nhs.uk/policies-resources/trust-policy-documents/trust-wide-

clinical/gen/163tdc33/?locale=en

Background

Antimicrobial agents are among the most commonly prescribed drugs and account for 20% of the hospital pharmacy budget. Unfortunately, the benefits of antibiotics to individual patients are compromised by the development of bacterial drug resistance. Resistance is a

natural and inevitable result of exposing bacteria to antimicrobials. Good antimicrobial prescribing will help to reduce the rate at which antibiotic resistance emerges and spreads. It will also minimise the many side effects associated with antibiotic

prescribing, such as Clostridium difficile infection. It should be borne in mind that antibiotics are not needed for simple coughs and colds. In some clinical situations, where infection is one of several possibilities and the patient is not showing signs of systemic sepsis, a wait and see approach to antibiotic prescribing is often justified while relevant cultures are

performed.

What is new in this version?

Warning added in section 5.1 to avoid gentamicin in patients who have recently received renotoxic chemotherapy.

Unit of measurement for renal function changed from eGFR to creatinine clearance (CrCl) as per MHRA Drug Safety Update: Prescribing medicines in renal impairment:

using the appropriate estimate of renal function to avoid the risk of adverse drug reactions

Link added to MD+Calc Creatinine Clearance (Cockcroft-Gault Equation) calculator

Guideline

1. Important Principles

Gentamicin should be used with extreme caution in patients with acute kidney injury* (AKI). If use in AKI is considered (for example due to septic shock or multiresistant pathogens)

then it should be discussed with a senior doctor (ST3 or above). Patients with reduced CrCl without previous CrCl results should be assumed to have AKI until proven otherwise. Gentamicin should not be administered to patients who have received reno-toxic

systemic anticancer treatment within the last 7 days (cisplatin, carboplatin,

http://intranet.srht.nhs.uk/policies-resources/trust-policy-documents/topics-prescriptions/antibiotic/antibiotic-prescribing-principles/144tdc25a5/

http://intranet.srht.nhs.uk/policies-resources/trust-policy-documents/topics-prescriptions/antibiotic/antibiotic-prescribing-principles/144tdc25a5/

http://intranet.srht.nhs.uk/policies-resources/trust-policy-documents/trust-wide-clinical/gen/163tdc33/?locale=en

http://intranet.srht.nhs.uk/policies-resources/trust-policy-documents/trust-wide-clinical/gen/163tdc33/?locale=en



oxaliplatin, ifosfamide, high dose methotrexate ≥ 3g/m2, trabectedin) due to the risk of renal toxicity.

Gentamicin should also be used with caution in the following groups, and discussed with a senior doctor (ST3 or above) if used:

- Renal transplant - CKD 4-5 (CrCl <30)

- Patients on dialysis Gentamicin is contraindicated in myasthenia gravis, and should be avoided wherever possible in severe visual impairment/blindness due to the potential serious sequelae should

ototoxicity occur. * AKI is defined as serum creatinine rise by ≥ 26µmol/L within 48 hours or

serum creatinine rises ≥ 1.5 fold from the reference value, which is known or presumed to

have occurred within one week or urine output is < 0.5ml/kg/hr for >6 consecutive hours

2. Remit of this guideline

Once daily (“consolidated”) gentamicin may be dosed at 4-7mg/kg according to the literature. To enable ease of dosing ~5mg/kg has been recommended as the starting dose at SRFT.

This guideline is not appropriate in patients with: - Endocarditis

- Pregnancy

- Cystic fibrosis

- Major burns (>20%)

- Ascites

- Renal dialysis or end stage renal disease (seek pharmacy advice)

Please check whether the patient has had a dose of gentamicin within the preceding 20 hours (e.g. in AED or theatres) before prescribing

3. Dose Calculation

For underweight patients, actual body weight should be used to dose aminoglycosides.

For patients who are more than 20% over their lean or ideal body weight, an adjusted drug dosing weight should be used when dosing aminoglycosides.

The adjusted body weight (ABW) includes a correction factor and may be calculated from: ABW = Ideal body weight (IBW) + 40% of excess body weight (EBW)

Excess Body Weight (EBW) = actual body weight – ideal body weight



IBW may be calculated from:

Males: 50Kg +2.3Kg for every inch over 5 Feet Females: 45.4Kg + 2.3Kg for every inch over 5 feet

Tables have been prepared for ease of gentamicin dosing. Tables are to be used to guide

the INITIAL DOSING ONLY. After this, advice should be sought from the ward pharmacist. There are two tables to choose from:

Table 1 – For patients with a CrCl>30ml/min

Table 2 – For patients with a CrCl<30ml/min **

** NB: For patients at higher risk of renal impairment including the elderly, frail or those who are haemodynamically compromised e.g. dehydration or shock (cardiogenic, septic), ‘Table 2’ may be used at the doctor’s discretion.

Creatinine clearance may be calculated using an online calculator available at MD+ Calc https://www.mdcalc.com/creatinine-clearance-cockcroft-gault-equation

https://www.mdcalc.com/creatinine-clearance-cockcroft-gault-equation



Step 3 - Refer to Table 1 for first dose

Step 1 - Determine patient’s height (cm) and weight (kg) and CrCl A creatinine clearance calculator is available here

If the patient’s actual weight is unknown, use ideal body weight (IBW) estimated from patient’s height.

YES NO

Step 3 - Refer to Table 2 for first dose

Step 4 - Give the first dose of IV gentamicin over 30 minutes and record the actual time of dose

Step 2- Does the patient meet any of the following criteria? (a) CrCl <30ml/min (b) > 75 years

(c) frail or haemodynamically compromised (e.g. dehydration/shock)

NB: If patient is <50kg, use Actual Body weight to calculate dose (5mg/kg if patient does not meet criteria in Step 2 or 3mg/kg if they do)

Step 5 - Take blood for serum gentamicin level

Step 6 - Give the second dose of gentamicin – no need to wait for

level results

Step 7 - Review results - is the trough level <1mg/L ?

Step 6 - Take blood for serum

gentamicin level BEFORE second dose is given

Only re-dose once level <1mg/L

Continue on current dose –

repeat levels twice weekly

Seek advice from ward

pharmacist

NO

YES

Wait for a 20 – 24 hour interval

https://www.mdcalc.com/creatinine-clearance-cockcroft-gault-equation

Title : Antibiotic Guidelines: Once Daily Gentamicin


Table 1 – Gentamicin dosing table for CrCl >30mls/min (based upon 5mg/kg drug dosing weight).

NB:If patient is at risk of renal impairment i.e. >75 yrs, frail or haemodynamically compromised e.g. dehydration or shock consider using Table 2

The Ideal and Adjusted body weight calculations are already incorporated in this table e.g. if your patient weighs 150kg read across from the 146-150kg box

51-55

56-60 240mg

61-65 280mg

66-70

71-75 320mg

76-80

81-85 360mg

86-90

91-95

96-100 400mg

101-105

106-110

111-115 440mg

116-120

121-125

125-130 480mg

131-135

136-140

141-145 520mg

146-150

151-155

156-160 560mg

161-165

166-170

171-175 600mg

176-180

>180 640mg

152 155 157 160 163 165 168 170 173 175 178 180 183 185 188 190 193 196 198

5'3''

Actual

weight

(kg)*

6’6”

Approximate Height (cm)

5'1'' 6'5''6'1''5'11'' 6'3''5'9''5'7''5'5''

Approximate Height (Feet/inches)

5’ 5’2” 5’4” 5’6” 5’8” 5’10” 6’ 6’2” 6’4”



Table 2 – Gentamicin dosing table for CrCl<30ml/min and/or >75 years and/or frail or haemodynamically compromised

patients (e.g. dehydration/shock)

The Ideal and Adjusted body weight calculations are already incorporated in this table e.g. if your patient weighs 150kg read across from the 146-150kg box

51-55

56-60

61-65 160mg

66-70

71-75

76-80

81-85 200mg

86-90

91-95

96-100 240mg

101-105

106-110

111-115

116-120

121-125

125-130 280mg

131-135

136-140

141-145

146-150 320mg

151-155

156-160

161-165

166-170

171-175 360mg

176-180

>180

152 155 157 160 163 165 168 170 173 175 178 180 183 185 188 190 193 196 198

6'5''

Actual

weight

(kg)*

Approximate Height (cm)

5’

Approximate Height (Feet/inches)

5'1'' 5'3'' 5'5'' 5'7'' 5'9'' 5'11'' 6'1'' 6'3''6’2” 6’4” 6’6”6’5’10”5’8”5’6”5’4”5’2”



Roles and responsibilities

All clinical staff involved in the prescribing of antimicrobials to adhere to this policy including full documentation on EPMAR as detailed.

Monitoring document effectiveness

Key standards:

Document the Indication/rationale for antimicrobial therapy.

Review and document the patient’s allergy status.

Ensure the choice of antibiotic complies with the antibiotic guidelines.

Prescribe single dose antibiotics for surgical prophylaxis, unless policy states otherwise.

Administer antibiotic prophylaxis within 60 minutes prior to surgical incision (administration must be complete before the incision, and before inflation of the tourniquet when used)

Method(s):

Audits of compliance with the guideline will be conducted on a regular basis as part of the

Antibiotic stewardship monthly audit. Team responsible for monitoring: Ward Pharmacists

Frequency of monitoring: Once every three years. Process for reviewing results and ensuring improvements in performance: Monthly

compliance dashboards will be shared with the divisional leads, Antibiotic Steering Group

and Infection Control Committee.

Abbreviations and definitions

AKI – acute kidney injury

CrCl – creatinine clearance

TDM – therapeutic drug monitoring

CKD – chronic kidney disease

eGFR – estimated glomerular filtration rate

IBW – ideal bodyweight

ABW – adjusted bodyweight

EBW – excess bodyweight



References

1. Traynor A, Nafziger A, Bertino J. Aminoglycoside Dosing Weight Correction Factors

for Patients of Various Body Sizes. Antimicrobial agents and chemotherapy Feb.

1995, p. 545–548 Vol. 39, No. 2

2. Medicines and Healthcare Products Regulatory Agency (MHRA). Oct 2019. Drug

Safety Update: Prescribing medicines in renal impairment: using the appropriate

estimate of renal function to avoid the risk of adverse drug reactions.

https://www.gov.uk/drug-safety-update/prescribing-medicines-in-renal-impairment-

using-the-appropriate-estimate-of-renal-function-to-avoid-the-risk-of-adverse-drug-

reactions

https://www.gov.uk/drug-safety-update/prescribing-medicines-in-renal-impairment-using-the-appropriate-estimate-of-renal-function-to-avoid-the-risk-of-adverse-drug-reactions





Document Control Information

This section will be completed following committee approval

Policy Approval: Medicines Management Group

Chairperson: Dr Richard Cooper

Approval date: 20/1/20

Formal Committee decision (tick) Chairperson’s approval (tick)

Lead Author: SueWei Chong (on behalf of Antibiotic Steering Group)

Lead author contact details:

[email protected] 65819

Consultation List the persons or groups who have contributed to this policy. (please state which Care Organisation)

Name of person or group Role / Department / Committee (Care

Org) Date

Antibiotic steering group SRCO Nov 2018

Endorsement List the persons or groups who have seen given their support to this policy. (please state which Care Organisation)

Name of person or group Role / Department / Committee (Care

Org) Date

Antibiotic steering group SRCO Nov 2018

Keywords / phrases: Antibiotics, Infection, gentamicin, TDM

Communication plan:

The guideline will form part of the Trust Antibiotic Policy and thus can be accessed via the Antibiotic and Infection Control hotlinks area on the front page of Synapse. In addition, adherence to the policy will be encouraged through FY1 and FY2 teaching sessions. The policy will be implemented in all areas with electronic prescribing.

Document review arrangements:

This document will be reviewed by the author, or a nominated person, at least once every three years or earlier should a change in legislation, best practice or other change in circumstance dictate.

mailto:[email protected]



Equality Impact Assessment (EqIA) screening tool

Legislation requires that our documents consider the potential to affect groups differently, and eliminate or minimise this where possible. This process helps to reduce health inequalities by identifying where steps can be taken to ensure the same access, experience and outcomes are achieved across all groups of people. This may require you to do things

differently for some groups to reduce any potential differences. 1a) Have you undertaken any consultation/

involvement with service users, staff or other groups in relation to this document?

If yes, specify what.

Yes Discussions at Antibiotic Steering Group and Medicines Management Group.

1b) Have any amendments been made as a result? If yes, specify what.

Yes-see changes to policy section

2) Does this policy have the potential to affect any of the groups listed below differently? Place an X in the appropriate box: Yes, No or Unsure This may be linked to access, how the process/procedure is experienced, and/or intended outcomes. Prompts for consideration are provided, but are not an exhaustive list .

Protected Group Yes No Unsure

Age (e.g. are specific age groups excluded? Would the same process affect

age groups in different ways?) X

Sex (e.g. is gender neutral language used in the way the policy or information leaflet is written?)

X

Race (e.g. any specific needs identified for certain groups such as dress,

diet, individual care needs? Are interpretation and translation services required and do staff know how to book these?)

X

Religion & Belief (e.g. Jehovah Witness stance on blood transfusions; dietary needs that may conflict with medication offered.)

X

Sexual orientation (e.g. is inclusive language used? Are there different access/prevalence rates?)

X

Pregnancy & Maternity (e.g. are procedures suitable for pregnant and/or breastfeeding women?)

X

Marital status/civil partnership (e.g. would there be any difference because the individual is/is not married/in a civil partnership?)

X

Gender Reassignment (e.g. are there particular tests related to gender? Is

confidentiality of the patient or staff member maintained?) X

Human Rights (e.g. does it uphold the principles of Fairness, Respect,

Equality, Dignity and Autonomy?) X

Carers (e.g. is sufficient notice built in so can take time off work to attend appointment?)

X

Socio/economic (e.g. would there be any requirement or expectation that may not be able to be met by those on low or limited income, such as costs incurred?)

X

Disability (e.g. are information/questionnaires/consent forms available in different formats upon request? Are waiting areas suitable?) Includes hearing and/or visual impairments, physical disability, neurodevelopmental

X



impairments e.g. autism, mental health conditions, and long term conditions e.g. cancer.

Are there any adjustments that need to be made to ensure that people with disabilities have the same access to and outcomes from the service or employment activities as those without

disabilities? (e.g. allow extra time for appointments, allow advocates to be present in the room, having access to visual aids, removing requirement to wait in unsuitable environments, etc.)

X

3) Where you have identified that there are potential differences, what steps have you taken to mitigate these? Gentamicin is not recommended in pregnancy due to safety issues and this

is made clear in this document. There is an obstetric infection guideline available on the intranet to guide prescribers to appropriate alternatives to gentamicin (http://intranet.srht.nhs.uk/policies-resources/trust-policy-documents/topics-prescriptions/antibiotic/urology-obstetrics-and-gynaecology/144tdc25j2/

Guidelines for clinicians only and provide antibiotic recommendations for the treating clinician

4) Where you have identified adjustments would need to be made for those with

disabilities, what action has been taken? N/A

5) Where the policy, procedure, guidelines, patient information leaflet or project

impacts on patients how have you ensured that you have met the Accessible Information Standard – please state below:

……………………………………………………………………………………………………………

EDI Team / Champion only: does the above ensure compliance with Accessible Information Standard

o Yes

o No

If no, what additional mitigation is required:

Will this policy require a full impact assessment? No

Please state your rationale for the decision: (a full impact assessment will be required if you are unsure of the potential to affect a group differently, or if you believe there is a potential for it to affect a group differently and do not know how to mitigate

against this - Please contact the Inclusion and Equality team for advice on [email protected]) Author: Type/sign: Sue Wei Chong Date: 02/01/2020

Sign off from Equality Champion: Date:

http://intranet.srht.nhs.uk/policies-resources/trust-policy-documents/topics-prescriptions/antibiotic/urology-obstetrics-and-gynaecology/144tdc25j2/

http://intranet.srht.nhs.uk/policies-resources/trust-policy-documents/topics-prescriptions/antibiotic/urology-obstetrics-and-gynaecology/144tdc25j2/

mailto:[email protected]

Once Daily Gentamicin Antibiotic Guidelines

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Transcript of Once Daily Gentamicin Antibiotic Guidelines