Transcript Peri-operative management

Peri-operative management of
the dialysis patient
Pelonomi: Firm 4
Consultant: dr Flooks
Registrar: A vd Horst
Our patient
• 49yr lady from Rocklands
• Hypertensive nephropathy on chronic
haemodialysis
• Anterior abdominal wall mass ? Desmoid
tumor
• Excision biopsy
Special investigations
Na
K
Ur
Cr
135
3.2
3.0
214
Cor Ca 3.10
Mg 0.76
P
0.63
Liverfunctions: albumin 22
tot protein 76
rest normal
Special investigations
• FBC: wcc 8.4 x 109/ℓ
Hb 8.0g/dℓ
mcv 88.9fl
pl 416 x 109/ℓ
• Iron studies: serum iron 5.4ųmol/ℓ
transferrin 0.7g/ℓ
TF saturation 31%
Peri-operative management of the
dialysis patient
Increased morbidity and mortality
• High incidence of CAD and myocardial
dysfunction
• Difficulty in managing fluid and electrolytes potassium
• Inability to metabolize and excrete anaesthetic
and analgesic agents
• Bleeding complications
• Poor BP control: both hypo – and
hypertension
Issues of concern
1. Baseline lab evaluation
2. Anaemia
3. Nutritional status
4. Dialysis dose
5. Fluid and electrolyte management
6. BP control
7. Evaluation for cardiovascular disease
8. Correction of bleeding diathesis
9. Antibiotics
10. Glucose metabolism
11. IV access
12. Anaesthetic considerations
1. Laboratory evaluation
• Baseline investigations:
- electrolytes, urea and creatinine
- glucose
- albumin
- full blood count
- coagulation profile
- iron studies if anaemic
- drug levels - digoxin
2. Anaemia status
• Elective surgery: Hb 12-13g/dℓ
• Erythropoiesis stimulating agents (ESA)
Important, because post – operatively:
• transfusions are often needed due to blood loss
intra-operatively
• ESA – resistance
3. Nutrition
• Ability to heal post-surgery
• Protein catabolic rate and albumin should be
optimalized
• Stop drugs decreasing appetite
• Drugs to ameliorate gastroparesis
• Nutritional supplements
4. Intensive dialysis
• Unknown whether delivery of intensive
doses of dialysis prior to or during surgery
improves outcome (Uptodate)
• Discussion between the anaesthetist and the
nephrologist
5. Fluid and electrolyte
management
• Optimal volume status: estimation of the
amount of fluid lost and administered during
surgery
• Normal saline vs Ringer’s lactate
• Electrolytes – calcium and potassium
Hyperkalemia and
emergency surgery
• ECG – asses the physiological effect of
hyperkalemia
• Chronic renal failure patients – increased
tolerance
• ECG changes due to alteration in transcellular K⁺
gradient and not the absolute value
• CRF – increased total body and intracellular K⁺
= normal ECG
Course of action is based
on the clinical setting
If:
• no ECG changes,
• stable patient,
• K⁺ 6 – 6.2 mmol/ℓ == cont surgery
If :
• ECG changes present = dialysis
If no dialysis facilities
available:
• Medical treatment
- Calcium
- Insulin and dextrose
- Sodium bicarbonate
- β-stimulants
- Cation exchange resins
- can be give PR if NPO
- potential for post-op intestinal
necrosis
6. Blood pressure
control
Hypertension
1. Optimize volume status – optimal dry
weight
2. Parenteral antihypertensives:
labetolol, hydralazine ( with β – blocker)
diltiazem, nitroglycerine, nitroprusside
3. Post-op – normal oral antihypertensive
regimen, with close monitoring
Hypotension
1.
2.
3.
4.
5.
Excessive fluid removal
Left ventricle dysfunction
Autonomic dysfunction
Pericardial tamponade
Vasodilatation from opioids / anxiolytics
= Titration of anti-hypertensive treatment
7. Cardiovascular
evaluation
• 50% of dialysis patients have CVS disease
• American College of Cardiology / AHA
• Risk stratification
8. Bleeding tendency
• Increased tendency to bleeding
• Platelet dysfunction – uremia, anemia,
hyperparathyroidism, aspirin
• Bleeding time not recommended as
screening test pre-op, except for renal biopsy
and major vascular surgery
• Raising hkt, desmopressin, cryprecipitate,
dialysis, estrogen
9. Peri-operative
antibiotic use
• In accordance with general surgical guidelines
• Dose adjustments
• Loading dose unchanged
• Access procedures - fewer access infections
10. Glucose metabolism
• Better control @ home, than in hospital
-
change in physical activity
acute comorbid conditions
inability to ingest food
reality of surgery schedules
• Type 1 DM – brittle
- wide variations in glucose
metabolism
- serum ketones if DKA
• Type 2 DM – induction of hyperglycemia
- increased t½ of oral drugs
11. IV access
• Frequent IV lines may destroy future access
sites
• Avoid subclavian central lines = subclavian
stenosis
• CVP should not be placed on the same side as
the AV access
12. Anaesthetic
considerations
• Thiopental – doubled free fraction
• Ketamine – hypertension
• Propofol – hepatic metabolism
- well tolerated
• Succinylcholine – Hyperkalemia
- K < 5mmol/ℓ
- succinylmoncholine
• NDMR: pancuronium and gallamine renally
excreted = prolonged paralysis
atracurium, vercuronium
• Sedatives: benzo’s are protein bound = free
fraction in CRF
intermediate metabolites
Analgesia
• Opioids – fentanyl drug of choice
- avoid pethidine, propoxyphene
- effects of morphine prolonged
- half-life of metabolites prolonged
• Paracetamol can be used without any dose
adjustments
In short
In short
Peri-operative management of the dialysis
patient requires a focussed assessment of all
12 aspects, as well as careful liaison between
the physician, surgeon and anaesthetist.
Back to our patient
• She underwent surgery without any
complications.
• Histology: Lipoma
Thank you
Bibliography
• Uptodate
• Miller’s Anesthesia, 6th edition