hypernatremia – case discussion
TRANSCRIPT
HYPERNATREMIA – CASE DISCUSSION
Dr Sasidaran Kandasamy MD DM IDPCCM FPN
Lead Consultant Pediatric Intensivist & Head PICU
Advanced Pediatric Critical Care Center
Dr Mehta Multispecialty Hospitals – CHENNAI - INDIA
20/11/2020 NEPHKIDS 2020 ISN 1
Overview
• Basic Concepts [ Help to solve the Dysnatremia – clinical puzzle !!]
• Case Scenarios on Hypernatremia
Iso to Hypervolemic Hypernatremia [ To understand beyond Fluid prescription!!]
20/11/2020 NEPHKIDS 2020 ISN 2
Understand ‘Link between Na and Water’
• Baseline Na 140 mmol/L [ L – Water is the denominator !!]
• 10% decrease in plasma water – Increases Na to 154 mmol/L [+14]
• 10% Increase in plasma water – Decreases Na to 126 mmol/L [-14]
• Volume Preservation is the primary target in Water Homeostasis
• Maintaining Na 135 -145 mmol/L [Osmolality] is the secondary target
• When there are conflicting signals, Volume Preservation is the priority
20/11/2020 NEPHKIDS 2020 ISN 3
Understand ‘Lab indices useful in Dysnatremia’
1. Urine Osmolality
• Random urine osmolality 300-900 mOsm/Kg
• In dehydration, Urine Osmolality increases > 600
2. Serum Osmolality
• Normal Serum Osmolality 275-295 mOsm/Kg
• Calculated Osmolality:
2 x Na + 2 x K + Glucose /18 + BUN/2.8
3. FENa
• Better compared to spot Urine Na
• [U Na/P Na] x [P Cr/U Cr] x 100
• P Na and U Na in mmol/L
• P Cr and U Cr in µmol/L OR mg/dl
• Lower the FENa Better the TUBULAR REABSORPTION
20/11/2020 NEPHKIDS 2020 ISN 4
Understand ‘Differences in Dysnatremia – hypo Vs hyper’
Timeline Hyponatremia Correction Target Hypernatremia Correction Target
Minutes to hours Excessive correction may NOT be harmful Excessive correction may NOT be harmful
1 -2 days [< 48 hours] Avoid increasing Plasma Na >10mmol / L / day Excessive correction may NOT be harmful[2 mmol/L/hour till S.Na reaches 145mmol/L]
Unknown OR > 48 hours Avoid increasing Plasma Na >8 mmol /L / day Avoid decreasing Plasma Na > 0.5mmol/L/hour
20/11/2020 NEPHKIDS 2020 ISN 5
Iso to Hypervolemic Hypernatremia Algorithm1. Stabilization of ABC and Seizure control.
2. Estimate the VOLUME status: HYPERVOLEMIC - No fluid loss, weight gain, voiding urine
normally, edema, pulmonary edema and respiratory distress. Check ORS/formula
preparation for errors. Confirm by lab: Urine Na > 20 OR FENa > 2 + RFT to calculate eCrCl
3. IV Frusemide as infusion (0.1 - 0.2 mg/kg/hour) to reduce fluid overload. Meticulously
measure UO. Replace UO with Isolyte P or ¼ GNS.
4. Stop 3% Saline or NaHCO3
5. Consider KRT/RRT, if UO low OR Creatinine high (eCrCL < 20ml/min/m2) OR very high
serum Na > 180 OR multiple electrolyte disturbances
20/11/2020 NEPHKIDS 2020 ISN 6
Clinical Case Scenarios
20/11/2020 NEPHKIDS 2020 ISN 7
CASE A
0 D1 D2 D3 D4 D5 D6 D7 D8
• IV Ceftriaxone & Azithro
• IV Acyclovir, Artesunate
D1 - Intubated - P-SIMV+PSAnti-raised ICP measures
A – 5 years Male Child
Fever & Cough 2 days
Altered sensorium – 1 day
Investigation Reports
CSF: 4 cells All Lymphocytes
CSF: Protein & Sugar Normal
CSF: HSV PCR Negative
H1N1 – Positive - Added Oseltamivir
MP Smear – Negative – Artesunate Stopped
•MRI brain with contrast – Normal
•Autoimmune encephalitis considered: IVIG (2g/kg over 48 hours)Child status @ Admn:
• GCS 13/15 – Reducing GCS
• Stridulous breathing +
• Neck Stiffness +
• Positive Kernig’s sign
Febrile EncephalopathyH1N1 Meningoencephalitis
20/11/2020 NEPHKIDS 2020 ISN 8
Sodium trends in CASE A
144
152
159161
152
146
135
140
145
150
155
160
165
Day 1 Day 2 Day 3 Day 4 Day 5 Day 6
Sodium
• 0.9% Saline Maintenance[CHLORIDE Loading]
+ Other Nephrotoxic Medications
20/11/2020 NEPHKIDS 2020 ISN 9
• 3% Saline• Mannitol• IVIG
10 ml/Kg NS x 2
Consequences of Hypernatremia in critically ill
20/11/2020 NEPHKIDS 2020 ISN 10
Creatinine trends in CASE A
0.8
1.9
1.6
1.2
0.7
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
Day 1 Day 3 Day 4 Day 5 Day 6
Creatinine
• Day 3: Creatinine Max 1.9
• eCrCL: 13ml/min/1.73m2 [<20 ml/min/1.73m2 ]
• USG: Mild Hepatomegaly &Renomegaly
• Hypertensive for 72 hours from D3
• D3 Cumulative FO% 3.5% / UO on D3 0.5 ml/kg/hr.
0.9% Saline Bolus 10 ml/Kg x 2
• 3% Saline• Mannitol• Acyclovir• IVIG
• MRI Contrast• Oseltamivir
20/11/2020 NEPHKIDS 2020 ISN 11
Basic principles to prevent NTMx – AKI [In LMIC !!]
1. Check on Circulatory Volume – Keep Euvolemic
2. Always Check Drug-Drug Interaction/ Additive Side Effects when prescribe Polypharmacy
3. Endorse the role of Clinical Pharmacist atleast in Speciality / Super-speciality / ICU units
4. Simple NTMx Checklist may be of use
5. Avoid Aminoglycosides – If no drug level monitoring available
6. Avoid Vancomycin – If no drug level monitoring available
20/11/2020 NEPHKIDS 2020 ISN 12
Common Nephrotoxic Drugs & Mechanism• NSAIDs
• ACEI
• ARB
• Calcineurin Inhibitors
• Drug Combinations [Clarithro + Amlodepine]
• Aminoglycosides
• Amphotericin B
• Chemotherapy Drugs
• ART
• Radio-contrast
• Beta Lactam Antibiotics
• PP Inhibitors, Diuretics
• Phenytoin, Valproate
• Acyclovir
• Ganciclovir
• Foscarnet
• ART
• Mannitol, IVIG, HES
Hemodynamic Changes
ATI
AIN
Intra-tubular Precipitation
Osmotic Nephrosis20/11/2020 NEPHKIDS 2020 ISN 13
CAUTION: Intravenous
Fluid – A Drug !
20/11/2020NEPHKIDS 2020 ISN 14
Management of Index Child
1. IV Frusemide as infusion (0.1 - 0.2 mg/kg/hour) to reduce fluid overload.
2. 4 hourly UO to decide next 4 hours IVF.
3. UO Replacement with ½ DNS.
4. Stopped 3% Saline, Mannitol & Other NTMx medications [Acyclovir]
5. Tolerated Na levels upto 155 mmol/L in view of primary CNS disease in index child
6. Frusemide responsiveness + Favorable Trajectory of Na & Cr
[Trend of decline in Cr & Na] – > Avoided KRT/RRT
20/11/2020 NEPHKIDS 2020 ISN 15
CASE B
0 4 Days. 2hr. 4hr. 8hr.
E – 5 years Male Child
Fever 4 days
Cough & Cold 4 days
Lethargy & depressed sensorium 24 hours
Reduced UO for 24 hours
<----Fever – More than 101 F -->
SEPTIC SHOCK
Fluid Bolus + Epi 0.1 mcg/kg/min
Antibiotics – Vanco + Piptaz
Catecholamine Resistant Shock
Epi 0.3 mcg + NE 0.2 mcg
Hydrocortisone – Shock dose
Ascorbic Acid + Thiamine IV
Ulinastatin started
Admission in PICU
IntubationMechanical VentilationCVL & Art LineLactate 6 EF 45%
20/11/2020NEPHKIDS 2020 ISN 16
Further Course in CASE B….
7 hours In PICU
• Persistent Cold & dusky Peripheries & SpO2 – 70-86 % in ear probe
• Poor PP, Central Pulse + (Poor); IA-BP – SBP 76-82 mmHg
• Adr 0.3 mcg/kg/min + NE 0.2 mcg/kg/min
• Ill sustained Response to Fluid bolus
• Increasing RR (50/min); HR 180-200/min
• ABG: 7.17/94/28/11. Lactate 6
• UO – 0.8 ml/kg/hour since admission
D1
Serum Na 176
Urea 78
Cr 1.1
SGOT 690
SGPT 296
CPK 48,000
Platelet 66,000
PT/APTT 35/55
INR 3.6
Lactate 6
20/11/2020 NEPHKIDS 2020 ISN 17
RRT Options in Critically ill Children
Intermittent Haemodialysis - IHD
Prolonged Intermittent Renal Replacement Therapy – PIRRT Or SLEDD
Continuous Renal Replacement Therapy - CRRT
Acute Peritoneal Dialysis - PD
20/11/2020 NEPHKIDS 2020 ISN 18
Acute PD - Prescription
Components Prescription Guidelines
Catheter Selection • Tenchoff Catheter/ Cook MPD catheter (Optimum Care)• Stiff Stylet Catheter (Minimum Standard)
Exchange volume • Initial Fill volume 10-20 ml/Kg• Maximum Fill volume 30 ml/Kg• Maximum 800 ml/m2 if less than 2years age• Maximum 1100ml/m2 if more than 2 years age• Higher fill volume give greater UF and Clearance
Dialysatecomposition
• Bicarbonate Dialysate [Shock, LF, Newborn] (Optimum Care)• Standard Dialysate• 1.5% Dx to start with – 2.5% to increase UFR
Exchange time • Initial Exchange time 1 hour: 10 min Inflow & 20 min Outflow• Standard Dwell time 30 min• Shorter dwell – Rapid Fluid, Urea, K removal• Hypernatremia – Longer dwell & Reduce Dx%
Additives • Heparin 250 IU/L• K 4meq/L
20/11/2020 NEPHKIDS 2020 ISN
19
Modifications warranted in HypernatremiaComponents Prescription GuidelinesCatheter Selection • Tenchoff Catheter/ Cook MPD catheter (Optimum Care)
• Stiff Stylet Catheter (Minimum Standard)
Exchange volume • Initial Fill volume 10-20 ml/Kg• Maximum Fill volume 30 ml/Kg• Maximum 800 ml/m2 if less than 2years age• Maximum 1100ml/m2 if more than 2 years age
Dialysate composition • Bicarbonate Dialysate [Shock, LF, Newborn] (Optimum Care)• Standard Dialysate [Lactate/ Acetate based]
PD 1.7 [1000 ml Bottle] Dianeal ® Baxter
Na 130 mmol/L Na 132 mmol/L
Cl 100 mmol/L Cl 95
Dx 1.7% 1.5/2.5/4.25 %
Acetate based Solution Lactate based solution
In Hypernatremia – Na >150 mmol/L
Add 3% Saline of calculated volume to keep
∆ Na [ Patient Na- Dialysate Na] = 15 mmol/L
4 hourly Na monitoring is needed to titrate further
20/11/2020 NEPHKIDS 2020 ISN 20
Sodium trends in CASE B
176 180172 166 165
155 152144
0
20
40
60
80
100
120
140
160
180
200
0 hr 8 hr 12 hr 16 hr 24 hr 48 hr 72 hr 96 hr
Sodium
Weight 16Kg; Duration – 5 days
CVVHDF through Rt IJV Line
Filter – M60 Prismaflex cassette. [2 in 5 days]
QB – 50 increased to 90 ml/min
QD – 200 ml/hour; QR – 500 ml/hour [300 pre+ 200 post]
Effluent dose – 44 ml/Kg/hour
CVVHDF
MRSA SepsisMODS
Rate of Na Fall in 16 hours – 1mmol/L/hour
20/11/2020 NEPHKIDS 2020 ISN 21
Creatinine trends in CASE B
1.2
1.4 1.4
1.1
0.7
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
Day 1 Day 3 Day 4 Day 5 Day 6
Creatinine
CVVHDF
Weight 16Kg; Duration – 5 days
CVVHDF through Rt IJV Line
Effluent dose – 44 ml/Kg/hour
PLEX
Filter – TPE 2000 cassette
1.5 times Plasma volume exchange x 2
CRRT StoppedNo further PLEXMinimal Ventilation SupportNo bleeds
20/11/2020 NEPHKIDS 2020 ISN 22
CVVHDF Prescription
Components Prescription Guidelines
Access Selection • IJV/ Femoral Vein• 7F/ 8F/ 10F/ 11.5F Dialysis Catheter• Check Good Forward & Return Flow
Blood Flow RateQB
• 4-5 ml/kg/min• Start at lesser flow and reach 50 – 100 ml/min
Dialyzer/ Filter • HF20 / M60 /M100• HF 20 – Only if weight < 10 Kg
Dialysate Rate QD
Replacement Rate QR
• QD + QF = 2 – 3L/ 1.73m2/ hour• Effluent dose = [QD + QF] – Patient Removal per hour• Target Effluent Dose = 35 ml/Kg/ hour• QD: QF = 1: 1 proportion• QF = 70 % Pre-filter & 30% Post Filter
Anticoagulation • Heparin 20 U/Kg loading followed by 5 - 10U/Kg/hour• NS Flush 50 – 70 ml once in 2 hours [If No Heparin]• APTT Target 50 - 90• ACT Target – 180 - 220
20/11/2020 NEPHKIDS 2020 ISN23
CVVHDF - Modifications in Hypernatremia
20/11/2020 NEPHKIDS 2020 ISN 24
1. Add 3% Saline of pre-calculated volume to make REPLACEMENT Fluid Na = 150-155 meq/L
2. 3% NaCl Volume = [(Target Na – 140)/ (513 – 140)] x Replacement Fluid Rate [ml/hour]
In Index child – QR 500ml/hour
= [(150-140) / (373)] x 500 = 13.5 ml to 500 ml =135 ml to 5L bag
This may be Empirical Best possible Starting point
3. Any rapid fall more than anticipated Na Gradient may mandate Peripheral IV 3% Saline Infusion
4. If Acute Hypernatremia
Na Fall 1-2 mmol/hour is acceptable [ Faster than this…. only in SALT poisoning]
Summary Points
1. Hypernatremia is due to – ‘SALT Gain Vs Excess Electrolyte Free Water Loss’
2. Critically ill children with Hypernatremia – Cause Multifactorial & Effect Multisystemic !!
3. Fluid Therapy Vs KRT in treating Hypernatremia is based on ‘Response Trajectory & AKI Severity’
4. Most of KRT Modifications in Hypernatremia are only ‘Best Empirical Start Point’
5. Monitoring S.Na / S.Cl / Cr / Venous pH may help in ‘Safe & Staggered Na Reduction’
6. Keep stock of Na containing medications & diluents in view of Na Load in index child
7. Keep your Na Targets Individualistic & Context Specific [ Ex S.Na 150-155 in a child with TBI]
20/11/2020 NEPHKIDS 2020 ISN 25
THANK YOU
Dr Sasidaran Kandasamy MD DM IDPCCM FPN
Email: [email protected]
20/11/2020 NEPHKIDS 2020 ISN 26
AKI Stages – KDIGO 2012
Stages Serum Creatinine Urine Output1 1.5 to 1.9 times Baseline Creatinine
OR> 0.3mg/dl Increase
<0.5ml/kg/hour for 6-12 hours
2 2.0 to 2.9 times Baseline Creatinine <0.5ml/kg/hour for > 12 hours
3 ≥ 3 times Baseline Creatinine ORCreatinine Increased to > 4.0 mg/dl ORInitiation of Renal Replacement Therapy ORIn patients < 18 years – Decrease in eGFR to < 35 ml/min/1.73m2
< 0.3ml/Kg/ hour for > 24 hoursORAnuria for > 12 hours
20/11/2020 NEPHKIDS 2020 ISN 27