Renal Failure and Dialysis in Pregnancy
By:David Shure
Differential Diagnosis
* FSGS -
Pro: HTN, non-remitting, albumin close to NL
Con: expected creatinine to be higher after several years
* Membranous Nephropathy -
Pro: wax/waning course
Con: often with lower albumin, edema
* Diabetic Nephropathy -
Pro: proteinuria, time course
Con:poor evidence for DM
4. FMD - Pro: unequal sized kidneys, young female, HTN hx, renal arteries not commented on in US
Nephrology Consult
* Is there any indication and/ or benefit to the fetus if we begin HD at this time?
* Can we preserve any residual maternal renal function?
* OB team trying to prolong in-utero growth/ length of pregnancy, not sure if pt is masking severe preeclampsia
Why did Ob Deliver the Baby?
* 7/21 pt c/o HA, and 7/23 severe RUQ tenderness and epigastric pain, decision made to deliver fetus based on:
* Severe superimposed Preeclampsia in setting of chronic HTN
* Also, mild thrombocytopenic further led to diagnosis of severe preeclampsia
Normal Physiologic Alterations of Pregnancy
Normal Renal Alterations in Pregnancy
Changes in GFR
* GFR and RBF rise markedly
* Glomerular hyperfiltration results in normal reduction in the plasma creatinine concentration to about 0.4 to 0.5 mg/dL
* Blood urea nitrogen (BUN) and uric acid levels fall for the same reason
Effects of Pregnancy on Renal Disease
* ― cases proteinuria worsen
* ž cases HTN develops
* Worsening edema if nephrotic
* 0-10% women with NL or mild reduction in GFR have permanent decline in renal function
Views on Pregnancy and Dialysis
* ‘Children of women with renal disease used to be born dangerously or not at all - not at all if their doctors had their way’, Lancet, 1975
* ‘Show me a method of birth control more effective than end stage renal disease’, Roger Rodby MD, 1991
* ‘Even if a woman on CAPD ovulates, doesn’t the egg just float away?’, Rodby, 1992
Why don’t uremic women get pregnant?
* Most beyond child bearing age
* Libido/ frequency of intercourse reduced
* Don’t ovulate
* Absence of increase in basal body temperature during the luteal phase of cycle
* Elevated circulating prolactin concentrations
* Elevated PRL impairs hypothalamic-pit function
Actually, they do get pregnant!
* 1st successful term pregnancy in 35 y/o dialysed pt in 1971, Confortini, et al.
* Yr 2000: >15,000 women of childbearing age getting dialysis
* For every person w/CKD 5, 20 have CKD 3 or 4 w/GFR <60, suggesting ~300,000 women w/CKD potentially able to bear children
Course of Renal Disease in Pregnancy
* Baseline azotemia = more rapid deterioration
* As renal dz progresses, ability to maintain nl pregnancy deteriorates, and presence of HTN incr likelihood of renal deterioration
* Renal dysfunction - greater risk for complications incl preeclapsia, premature delivery, IUGR
Pregancy during dialysis: case report and management guidelines; Giatras, et al. 1998
* 32 y/o AA woman, G4, P2, A1
* FSGS and chronic interstitial nephritis
* Renal/obstetric protocol implemented
* Increased HD to 4 hrs/ 4 sessions/ week maintain prediaysis BUN <50
* At each HD session, blood flow gradually increased over 1st 30 minutes of HD, from 180 to 300 ml/min
* Kt/V 1.02 - 1.66
Giatras Protocol
* Dialysis performed in left lateral decubitus position
* Est maternal dry wt incrased by 500 g every 10d
* EPO administered at each HD session, to maintain HCT 32-34%
* Vit D, folic acid and MVI admin
* Evid of malnutrition prior to pregnancy, so 3000kcal/day diet w>100g protein/ day
Obstetric Surveillance
* From 25 wks gestation
* Serial BP
* Uterine and umbilical artery perfusion evaluation
* Cont fetal heart rate tracing before, during and after HD
* There were no signif changes in uterine or umbilical artery S/D ratios at any time of HD, and no sig alteration in maternal MAP during HD
* Pt delivered at 32 wks gestation, due to PROM
Common Themes in Dialysing Pregnant Patients
1. Keeping BUN < 50
2. Increasing dialysis time and frequency
3. BP control
4. Managing anemia with increasing doses of ESA
5. Fetal monitoring once viability reached
BUN <50 Hypothesis?
* 1963 150 women varying degrees of CKD, none on dialysis, found the single most important factor influencing fetal outcome was BUN
* Fetal mortality directly proportional to BUN
* Hypothesis: intensive dialysis in pregnant women w/renal dz might improve fetal outcomes
Increasing frequency and
time on dialysis?
* May be beneficial in reducing incidence of polyhydramnios by reducing urea and water load
* Less dialysis-induced hypotension
* More liberal diet
* American Jrnl Kid Diseases
* Spurred by the report of 5 pregnancies in 5 pts on chronic HD in 2 dialysis units bet 1989-1996
* 1st national survey of its kind which revealed a total of 15 pregnancies in HD - all dialysis centers in Belgium questioned for pts bet 1975-1996
Study Population Figures
Case Characteristics/ Outcomes
Dialysis Dosing
* 15 pregnancies went beyond 1st trimester
* Frequency of HD was increased immediately or progressively to 16 to 24 hrs
* No difference bet successful pregnancies and failed ones for # mths on HD prior to conception or age at conception.
* For successful pregnancies + correlation bet birth wt and excess dialysis hrs delivered over entire pregnancy.
Success Rate
* 80% (4/5) when HD initiated after onset of pregnancy (pregnancy first)
* 50% (5/10) when HD was the first event
* ‘‘Pregnancy first’ cases have a significant residual renal function and even may benefit from ‘preventive dialysis’, to be taken on dialysis at a stage of renal failure that would not justify dialysis in the eyes of many were it not for the very special setting of a pregnant state’’
Obstetrical Problems
* Main Problem: premature births
* In this study 3 died due to severe prematurity
* Polyhydramnios present in almost all cases, may be cause of preterm labor
* Growth retarded babies at highest risk for intrauterine death
* Maternal prognosis is good
Should we Initiate Dialysis in Pts w/Low Cr Clearance?
* Hou, S., Pregnancy in Women on Hemodialysis, 1994, revealed better outcomes of pregnancy in women w/ significant residual renal function or who initiate pregnancy before they need dialysis.
* May reduce incidence of polyhydramnios, lower urea and lowers water load, also reducing risk of dialysis-induced hypotension
Registry of Pregnancy in Dialysis Patients
USRDS
Frequency of Prematurity and Low Birth Rate is less in those conceived before beginning dialysis
Women who Start Dialysis During Pregnancy
* Likelihood of infant surviving is good
* Termination of a pregnancy after renal function has begun to deteriorate rarely rescues the kidneys
* NEJM, Jones and Hayslett, 1996, looked at 82 pregnancies in 67 women w/CRI, only 15% of those w/deteriorating renal function had a return of renal function to baseline in 6 mths post partum
Survival Statistics
Renal Failure and Dialysis in Pregnancy.ppt
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