NEUROLOGICAL INJURY and RENAL REPLACEMENT THERAPY Lina C. Laxamana, FPCP, FPNA Neurocritical Care Unit October 8, 2010 NKTI Post Graduate Course.

NEUROLOGICAL INJURY and RENAL REPLACEMENT

THERAPY

Lina C. Laxamana, FPCP, FPNANeurocritical Care Unit

October 8, 2010NKTI Post Graduate Course

Renal Replacement Therapy• Indications:– Severe hyperkalemia– Fluid overload– Refractory acidosis– Uremic symptoms:• Serositis• Encephalopathy• Bleeding

• Objectives:– Remove excess volume– Remove solutes

Renal Replacement Therapy

Intensity of RRT and outcome in critically ill patients with ARF

CASE

• M.B., 56/M, married, from Isabela • Admitted due to sudden onset of R sided

weakness and aphasia • ~11 hours PTA– Sudden onset of R sided weakness, with aphasia– Brought to a local hospital– Cranial CT requested

Imaging ( 2 ½ hours)

Imaging (2 ½ hours)

Imaging (2 ½ hours)

Imaging (2 ½ hours)

Imaging (2 ½ hours)

• Intracerebral hematoma with an estimated volume of 30cc in the L capsuloganglionic region.

• With perilesional edema, mass effect and midline shift

• No IVE, HCP

Case • PMHx–With HPN, DM II, CAD–With ESRD requiring HD every 5th day

through a L brachial AV fistula–Maintained on Plavix 75mg/tab, ½ tab daily–Denies allergies

• PSHx–unremarkable

Pertinent examination • E4V2M6• Cranial nerves–Pupils 2mm EBRTL–R central facial palsy–Good gag– Tongue deviated to the R

• Motors UE R 0/5 L 5/5 LE R 0/5 L 5/5

Case • Pertinent labs–CBC 13.3/44.1/11.1/N92/249–BT 4’ CT 5’–PTT 35.1s PT 85% INR 1.06–Na 127 K 5.89 –BUN 34 Crea 6.77

• Cranial CT repeated

Imaging (10 ½ hours)

Imaging (10 ½ hours)

Imaging (10 ½ hours)

• L capsuloganglionic acute intraparenchymal hematoma (42cc)

• Surrounding edema

• Compression of the ipsilateral ventricle and slight midline shift to the right

Case • Admitted to NCCU–Started on Mannitol 60gms q4–Neuro status quo: E4v2m6•Pupils 2mm EBRTL• Slight headache

–Started on HD

Day 2 • Day 3 post ictus (830am)– E2v1m6, drowsier–BP 150/90 HR 90 O2sat 95% T 37.8C –Pupils 1mm, equal–Na 126 (124) K 5.89 (6.26)– Stat CT scan requested• NPO• Additional Mannitol 30gms bolus given

Imaging (day 2)

Imaging (day 2)

Imaging (day 2)

Imaging (day 2)

• Interval evolution to beginning subacute stage

• Without increase in volume

• Interval progression of perilesional edema

• Midline shift to the right has not significantly changed

Case • Day 3 post ictus (915am)

–Prepared for surgery–Repeat PT 138% INR 0.88 PTT 31.1s –Na and K correction–Mannitol continued at 60gms q4–Hemodialysis–Clearances requested

Case • Day 3 post ictus (1110am)– Elective intubation done (Anes)

• Day 3 post ictus (515pm)– E2vtm5, more difficult to arouse–BP 166/100 HR 90 O2sat 100%–Pupils 2-3mm EBRTL–Awaiting repeat labs post HD

Case • Day 3 post ictus (10pm)–K 4.35– Scheduled for surgery at 4am

• Day 4 post ictus (120am)– E2vtm5–BP 160/90 HR 88 O2sat 98%–Pupils 2-3mm EBRTL

Case • Day 4 post ictus (4am)–OR

• Plan– L frontal craniotomy, endoscopic

evacuation of hematoma with intraparenchymal ICP monitor probe insertion

Case • Goals for treatment–Address the increased intracranial pressure

from the hematoma– Evacuate the capsuloganglionic hemorrhage– Lessen the need for osmotic diuretics in an

ESRD patient

Surgery

Surgery

Surgery

Surgery

4th day post-op

Renal Replacement Therapy and the

Neurocritical Care Patient

Lang & Chestnut, Neurosurg Clin N Am 1994;5(4):573-605

Cerebral Blood Flow

Cerebral Blood Flow

Bhardwaj A. Cerebral blood flow. In Suarez JI, Critical Care Neurology and Neurosurgery, Humana Press, 2004 with permission

• MAP = 2 (diastolic) + systolic 3• CPP = MAP - ICP• CBF = Cerebral Perfusion Pressure Cerebral Vascular Resistance =P x x r4 / 8 x L x (Hagen-Poiseuille equation for movement of Newtonian fluids in large caliber vessels)• Autoregulation: MAP 60-150 mmHg

IHD and ICP

From: Davenport A. Hemod Internl 2008;12:307–312 with permission

MAP and CAPD

From: Davenport A. Hemod Internl 2008;12:307–312 with permission

Effect of renal replacement on ICP

From: Davenport A. Semin Dialysis, 2009;22:165–168 with permission

Serum osmolality following renal replacement

From: Davenport A. Semin Dialysis, 2009;22:165–168 with permission

Modifications to standard hemodialysis prescription that may potentially reduce risk of further cerebral

injury in patients with acute cererbal injury

From: Davenport A. Hemod Internl 2008;12:307–312 with permission

Conclusion

• CRRT may have beneficial effects in patients with RIH

• Further research may be warranted

Fletcher et al, J Trauma, Critical Care ,2010

Has CRRT caused ICP reduction?

• Unknown mechanism• Removal of cytokines and myocardial

depressants seen with ultrafiltration and membrane absorption

Fletcher et al, J Trauma, Critical Care ,2010

Statement

• CRRT is the preferred mode in ABI• Previous studies did not show decrease in ICP

but rather only stability• patient population• mode of CRRT used • membrane biocompatibility

Davenport; Nephrol Dial Transplant. 1990;5:192–198 Br Med J (Clin Res Ed). 1987;295:1028.

Osmotherapy

• If elevations in ICP are noted or cerebral edema:– Treatment of ICP should continue as usual–20% mannitol infusions–Hypertonic saline with the dialysate to keep

serum sodium 150-155 mEq/L

Renal Failure and Neurosurgery

• Emergency surgical evacuation• Correct coagulopathy:–Platelet transfusion–DDAVP–Correct INR

• RRT as indicated above

Conclusions• Renal failure is common in the ICU• Less common in patients with neurological

injury• All risk factors should be corrected• Continuous replacement therapies are

preferred • Close communication and team work with

nephrologists are key

THANK YOU