Considerations, management and a case example with anaesthetic

protocol

Anaesthesia of the Diabetic

Patient

Case details

*8 year old labrador*32kg bodyweight*Requires surgery for removal of a large

lipoma in perineal region.*Has Diabetes Mellitus and receives 10iu of

Insulin in the morning and 15iu in the afternoon.*Owner monitors the dog’s glucose at

home and feel it is under good control.

Considerations for this case*32kg = within healthy weight range for adult

labrador.*Antimicrobial protocol*Insulin medication *Monitoring of blood glucose peri-operatively*Presence of concurrent disease*Hydration status & fluid administration*Analgesia *Recovery

Diabetes Mellitus – a brief summaryType 1: Destruction of insulin-producing Beta cells in the pacreas. Most common type seen in dogs. Usually immune-mediated and may be linked with pancreatitis.Type 2: Relative insufficiency of insulin – being produced but body has become resistant. Linked to obesity and seen in older, overweight dogs. Most common type in humans and cats.

Decreased insulin relative to requirement -> blood glucose cannot enter cells -> hyperglycaemia -> energy-deficient cells -> body utilises fat stores (may lead to ketosis and hepatic lipidosis).Prone to bacterial infection and UTIs (as excess blood glucose filtered through kidneys -> glucosuria).Other clinical signs include weight loss, PU/PD, polyphagia, lethargy…

Pre-op Preparation*Withhold food for 4-6 hours *Biochemistry and haematology to assess

function of kidneys, liver and to check for signs of underlying disease.*Urinalysis (glucose, ketones, protein,

RBCs)*Take a pre-op blood glucose measurement

Measuring glycaemia

Pre, intra and post-op measurements are essential. If patient hospitalised overnight, can take several measurements and create a blood glucose or fructosamine curve to determine how well-controlled the glycaemia is. Fructosamine levels:Control Fructosamine (umol/l)Normal range 225-375Excellent 350-400Good 400-450Fair 450-550Poor >550Prolonged hypoglycaemia

<300

Glucose levels

Should aim for between 5-10 during surgery (this is average blood glucose levels for a well-controlled diabetic dog).

Control Blood glucose (mmol/l)

Hypoglycaemic <3Minimum safe range for diabetic dog

3-5

Normal target range 5-10Maximum safe range for diabetic dog

10-20

Hyperglycaemic >20

Potential Problems and what to do about them

*Hyperglycaemia – administer insulin *Hypoglycaemia – dextrose infusion (2.5% or 5%

depending on severity)* Hypotension – IV fluid bolus

- Reduce vapouriser %- +ve ionotrope eg dopamine

*Hypothermia – warm patient up!

References used* De Vries M. Diabetes mellitus and anaesthesia: dealing with its

potential problems. Veterinary Times 2011; 27 http://www.vetsonline.com/publications/veterinary-times/archives/n-41-27/diabetes-mellitus-and-anaesthesia-dealing-with-its-potential-problems.html

* Oliver JAC, Clark L, Corletto F, Gould DJ. A comparison of anesthetic complications between diabetic and nondiabetic dogs undergoing phacoemulsification cataract surgery: a retrospective study. Veterinary Ophthalmology 2010; 13

* Panti A, Bradbrook C. Clinical Conundrum. BSAVA Companion 2012* 2010 AAHA Diabetes Management Guidelines for Dogs and Cats

https://www.aaha.org/professional/resources/diabetes_management.aspx#gsc.tab=0

* http://petdiabetes.wikia.com/wiki/Blood_sugar_guidelines* http://www.caninsulin.co.uk/

 

Pre-medication, induction, monitoring, and recovery of a diabetic dog

Carl’s big day

Pre-op

Clinical Exam

BAR – friendly,

calm

Starved overnight

IV catheter in right

cephalic vein

Blood Glucose

Pre-anaesthetic blood work

Blood glucose

<5 mmol/l

Pre-medication – 9am

Methadone – 0.3 mg/kg IV(9.6 mg)

ACP – 0.03 mg/kg IV(0.96

mg)

Surgery

Induction drugsPropofol – 4

mg/kg IV(128 mg)

IV fluids

Hartmann’s Soln – 5

ml/kg/hr (160 ml/hr)

5% Glucose infusion - 3 ml/kg/hr (64

ml/hr)

MonitoringMonitor blood

glucose every 30-60 minutes

Goal of 8.3-14 mmol/l

Vitals

Inhaled Gas

Isoflurane – 1.5-2.5% +

oxygen

Analgesia/ Antibiosis

Augmentin – 8.75 mg/kg (280 mg) IV

every 8 hours

Meloxicam – 0.2 mg/kg

(6.4 mg) SQ

Recovery

Anaesthetic

Discontinue isoflurane. Continue

oxygen via ET tube.

Extubate normally

Blood Glucose

Monitor every 30-60 minutes until fully awake

and able to eat

Discontinue glucose infusion and give a small

meal. Continue to monitor blood glucose

Evening dinner + 15 IU insulin. Resume normal

insulin routine

Analgesia/ Antibiosis

Methadone – 0.3 mg/kg IM (9.6 mg) every 4 hours until

9am

Meloxicam – 0.1 mg/kg (3.2 mg)

PO SID for 5 days

Augmentin – 12.5 mg/kg (400 mg) PO

BID for 7 days

Any questions?