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The incidence of acute renal failure has declined overrecent decades as a result of improved antenatal care and

the virtual elimination of post-abortal sepsis. Thirty years

ago the incidence of acute renal failure was 1 in 2000

pregnancies, and it is now 1 in 10,000 pregnancies.1,2

All obstetricians are faced with the problem of acute

renal failure in the second half of pregnancy. The causes

now prevalent include hypertensive disorders, hemor-

rhage, sepsis, intrinsic renal disease, and other rare preg-

nancy-related disorders. The management of patients

with acute renal failure caused by preeclampsia or

eclampsia differs geographically, according to the avail-

ability of resources and different perceptions of the dis-

ease.

Patients with preeclampsia have vasoconstriction, he-moconcentration, and a reduced intravascular volume;

therefore, they are particularly vulnerable to the effects

of blood loss. Antepartum hemorrhage (eg, abruptio pla-

centae) and postpartum hemorrhage reduce plasma vol-

ume and may lead rapidly to renal ischemia. Acute renal

failure in preeclampsia is often associated with placental

abruption.3

The largest obstetric review of renal failure of which we

are aware was published in 1990.3 This study, conducted

over 12 years, included 9600 women with hypertension:

1433 women had preeclampsia and 251 had eclampsia. Of

those women described in the study, only 31 developed

acute renal failure, all in the postpartum period. Fromthese 31 cases there were 2 maternal deaths, and 50% of

the patients in the preeclamptic group required dialysis.

All patients had acute tubular necrosis. In the chronic hy-

pertensive group with superimposed preeclampsia, 42%

required dialysis and 3 had cortical necrosis. Most impor-

tant is that all patients in the preeclamptic group had nor-

mal renal function at long-term follow-up (average, 4

years). The investigators concluded that appropriate treat-

ment in the women with preeclampsia resulted in the ab-

sence of long-term renal impairment. It is noteworthy that

From the Department of Obstetrics and Gynaecology, Groote Schuur Hos-pital.Received for publication March 16, 2001; revised June 18, 2001; ac-cepted September 12, 2001.Reprint requests: AJ Drakeley, MRCOG, Department of Obstetrics & Gy-naecology, Liverpool Womens Hospital, Crown Street, Liverpool L8 7SS,UK. E-mail: [email protected] or [email protected] 2002, Mosby, Inc. All rights reserved.0022-9378/2002 $35.00+0 6/1/120279doi:10.1067/mob.2002.120279

Acute renal failure complicating severe preeclampsia requiring

admission to an obstetric intensive care unit

Andrew J. Drakeley, MRCOG, Paul A. Le Roux, MBChB, John Anthony, FCOG(SA), and

James Penny, MD, MRCOG

Cape Town, South Africa

OBJECTIVE: To determine risk factors and outcomes for women with severe preeclampsia and renal failure.

STUDY DESIGN: Retrospective study from 1995 to 1998 of all women with renal failure who were admitted

to the obstetric intensive care unit at Groote Schuur Hospital, South Africa. A total of 89 women were identi-

fied with severe preeclampsia defined as blood pressure 160/110 mm Hg and 2+ proteinuria, renal failure

defined as a creatinine level of 1.13 mg/dL, and oliguria defined as


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254 Drakeley et al February 2002Am J Obstet Gynecol

these investigators managed their patients in a dedicated

obstetric intensive care unit (ICU) with facilities for inva-

sive monitoring. Another review by Sibai et al3 of 254

eclamptic patients showed that of the 12 patients requir-

ing dialysis, 1 patient died. The remaining 11 patients had

reversible acute tubular necrosis.

Renal failure is a serious complication of pregnancy,

with significant associated morbidity and mortality. We

evaluated the pregnancy-associated and, more particu-

larly, the preeclampsia-associated incidence and sequelae

of renal failure in a tertiary-care obstetric unit.

The objectives of our study were to determine manage-

ment, complications, and outcomes for women with se-

vere preeclampsia and acute renal failure in pregnancy.

Methods

Groote Schuur Hospital is a tertiary referral unit for

the entire metropolitan area of the Western Cape Penin-

sula of South Africa that covers 28,000 deliveries perannum. All medical problems that complicate pregnancy

are referred to the obstetric service at Groote Schuur

Hospital. The Maternity Centre at the hospital has an

obstetrician-led ICU, with facilities for ventilation and in-

vasive monitoring. At the time of this study, the majority

of hospital admissions were for complications of severe

preeclampsia. Other indications for admission were

hypovolemic shock caused by obstetric hemorrhage and

septic shock. A database of all ICU admissions is main-

tained, which documents indications for admission, com-

plications, need for invasive monitoring, and outcome.

Also included are biochemical and hematologic parame-

ters together with daily fluid balance.The obstetric ICU database was interrogated to identify

women with renal impairment (defined as a serum crea-

tinine level of 1.13 mg/dL and oliguria of 600 mol/L). The thresh-

olds for division were arbitrary but facilitated compar-

isons between women with different severities of disease.

The groups were compared for antenatal characteristics

and for postnatal outcomes. All women included in the

study were managed according to established depart-

mental protocols that remained consistent for the dura-

tion of the study.

All women with severe preeclampsia (persistent hyper-

tension at 160/110 mm Hg and 2+ proteinuria on dip-

stick) underwent a standardized management protocol.

Magnesium sulfate was prescribed to all women with se-

vere preeclampsia, and hydralazine was the hypotensive

agent of choice. Oliguria was intially managed with col-

loid fluid plasma substitute challenges. If there was no re-

sponse, then low-dose dopamine was prescribed and, if

necessary, a pulmonary artery flotation catheter was in-

serted to aid in hemodynamic management. Maternal

medical records were analyzed and data were extracted

pertaining to the indication for admission and progress

while in the ICU. Details of postnatal appointments were

also recorded, including blood pressure, proteinuria,

and renal biochemistry. For women who were transferred

to the renal unit for dialysis, renal clinic charts were ana-

lyzed for recovery of renal function to normal levels. Dis-cussion with the renal specialists with regard to data

interpretation and presentation was undertaken before

commencement of the study.

Results

During the 3-year study period, Groote Schuur Hospi-

tal provided tertiary care to a maternity population of

94,500 women, of whom 5200 had hypertensive compli-

cations of pregnancy. A total of 588 women were admit-

ted to the obstetric ICU. Of these, 89 had a blood

pressure reading of 160/110 mm Hg, a reading on

urine dipstick of 2+ proteinuria, and a serum creatinine

level of 1.13 mg/dL.Patient records were located for only 72 women; the re-

maining 17 records could not be found. Of the 72 women

identified, 38 had mildly elevated maximum creatinine

levels of between 1.13 and 2.25 mg/dL; 19 women had

moderately elevated creatinine levels of between 2.26 and

6.78 mg/dL, and 15 had severely elevated creatinine levels

of >6.78 mg/dL (Table I). In the majority of women, pre-

eclampsia was the underlying pathologic condition (67 of

72 cases). Other diagnoses included one each of diabetic

ketoacidosis, myocardial infarction, mixed mitral valve

disease, extra-uterine pregnancy and pulmonary embolus.

None of the women had a maximum creatinine level ex-

ceeding 2.26 mg/dL. In all of the remaining women, pre-eclampsia was the sole cause of acute renal failure. Fig 1

shows the pattern of creatinine levels in women within

each of the three groups in the first 7 days postpartum

(mild, diamond; moderate, square; and severe, triangle).

The diagnoses contributing to ICU admission are shown

in Table II. In some cases, multiple disorders contributed

to the womans renal compromise (eg, preeclampsia plus

abruptio placentae plus eclampsia plus HELLP).

In 14 of the 15 women with maximum creatinine levels

of >6.78 mg/dL, the women had either HELLP syndrome


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Volume 186, Number 2 Drakeley et al 255Am J Obstet Gynecol

(n = 11) or placental abruption (n = 5, of whom 2 also

had HELLP syndrome). In one woman with HELLP syn-

drome, the nadir of the platelet count was 103

109

/L,with maximum levels of lactate dehydrogenase and ala-

nine transaminase of 3200 U/L and 229 U/L, respec-

tively. One patient did not have HELLP or a placental

abruption, but had intrinsic renal disease exacerbated by

preeclampsia.

After diagnosis of acute tubular necrosis (persistent olig-

uria and rising creatinine level), standard management of

fluid restriction and close monitoring of blood chemistry

was instituted. Seven women required dialysis; in 5 cases

the indication was uremia. Two women required acute

dialysis because of fluid overload and pulmonary edema

that failed to respond to conventional management. None

of the women required dialysis because of electrolyte im-balance. In all of the cases referred for dialysis there was

subsequent improvement in renal function. None of the

women required long-term dialysis, the longest treatment

being 2 weeks. Nine women required treatment for hyper-

kalemia (potassium level of >7 mmol/L): 4 were treated

with intravenous insulin and dextrose and 5 were given

calcium resonium ion exchange resin. Forty-six women re-

quired pulmonary artery flotation catheters, invariably to

aid fluid management (Table III).

Renal impairment associated with preeclampsia was as-

sociated with a high incidence of perinatal mortality,

overall 38% (27/72), ranging from 26% in group 1 to

47% in group 3. There were no maternal deaths in thiscohort of women by the end of the study period (maxi-

mum follow-up 31/2 years). In addition, there was a high

incidence of hypertension (140/90 mm Hg) at 3-month

follow-up, although persistent proteinuria was relatively

uncommon (Table IV). In all but one woman who had re-

quired renal dialysis, the creatinine level had returned to

within normal limits by the time of discharge. In one case

the last recorded creatinine level was 1.82 mg/dL.

Because of limited and oversubscribed neonatal re-

sources, neonates with birth weights of 6.78Characteristic (n = 38) (n = 19) (n = 15)

Primigravid (%) 44 42 43Mean blood pressure 126/76 128/78 126/82

at booking(mm Hg)

N (%) without 5 (13) 3 (15) 1 (7)prior antenatalcare

Median weeks 32 (22-40) 32 (21-38) 32 (23-40)of gestationat delivery (range)

Fig. Creatinine trend over 1 week for the 3 groups of women.

Table II. Diagnoses contributing to admission to inten-

sive care unit according to creatinine levels

Creatinine level (mg/dL)

1.13-2.25 2.26-6.78 > 6.78Diagnosis (n = 38) (n = 19) (n = 15)

HELLP syndrome 12 9 11Abruptio placentae 9 (1 with 9 (1 with 5 (2 with

HELLP) HELLP) HELLP)Pulmonary edema 3 1 1Eclampsia 8 2 2Antenatal hypertension 2 2 3Antenatal chronic renal 2 1 1

failure

Data are number of women. HELLP, Hemolysis, elevated liverenzymes, and low platelet count.

Table III. Treatment according to creatinine level


Treatment 1.13-2.25 2.26-6.78 >6.78

Calcium resonium 0 2 3Insulin/dextrose 0 2 2Dialysis 0 0 7PAFC (Swan-Ganz catheter) 20 12 14CVP line 1 1 0

Data are number of women. CVP, Central venous pressure;PAFC, Pulmonary artery flotation catheter.

Table IV. Neonatal outcome and follow up for women

with preeclampsia


1.13-2.25 2.26-6.78 >6.78(n = 38) (n = 19) (n = 15)

Perinatal death, n (%) 10 (26%) 10 (53%) 7 (47%)Hypertensive at 6 of 8 who 3 of 9 who 5 of 9 who

3-month follow up attended attended attendedProteinuric at 0 of 8 who 5 of 9 who 0 of 9 who

3-month follow up attended attended attended


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256 Drakeley et al February 2002Am J Obstet Gynecol

ventilated. The severity of disease, late presentation, and

birth weight restriction for ventilation all contribute to

these high neonatal mortality rates.

Comment

This current study is unique in several aspects. The rel-

ative rarity of acute renal failure nowadays, compared

with data from 30 years ago is confirmed (1:1060). This

study reflects a higher rate of renal failure than does the

Sibais3,4 series; however, Sibai restricted his study to

women with HELLP syndrome. The difference in the in-

cidence of renal failure may be due to referral pattern,

population, or the definition employed. The current

study is a true population-based study because we run a

single and complete tiered obstetric service for an entire

metropolitan region. The incidence of HELLP syndrome

in our groups of acutely ill hypertensive women admitted

to the labor ward at Groote Schuur is 23%.5 The inci-

dence of women with renal failure who require dialysis islow and reliably quantifiable (7:94,500 or 1:13,500).

The prevalence of preeclampsia as a cause of acute

renal failure has been confirmed. The rarity of preexist-

ing medical disorders as contributory factors leading to

acute renal failure is in contrast to data presented in

some earlier published reports and may reflect an overall

improvement in the management of other conditions, es-

pecially those associated with an infective etiology.1,2

The most severe forms of renal failure occurred in

complicated preeclampsia, invariably HELLP5,6 syn-

drome and placental abruptions. It is uncertain whether

the favorable outcome reflects an aggressive fluid and

management protocol or the natural history of the con-dition. It is noteworthy that the risk of requiring dialysis is

highest in patients for whom the creatinine level doubles

in the first 24-48 hours post hospital admission, in the

presence of a major complication of preeclampsia.

This retrospective review cannot assess whether our

approach to management was beneficial (or harmful)

in either the short or long term. According to our un-

derstanding of the pathophysiology, the use of invasive

monitoring is consistent with goals of rational manage-

ment. A wider review in the same obstetric intensive

care unit showed this type of monitoring to be both

beneficial and relatively safe.6,7 The incidence of inva-

sive monitoring overall was low and if accepted to be

necessary would favor arguments that support the cre-

ation of dedicated units for the care of these women.

However, although the management protocol cannot

be evaluated in this series, it is reasonable to assert that

women with renal failure complicating severe pre-

eclampsia should be managed in a dedicated unit with

appropriate expertise to ensure that the good results

from this and series by Sibai et al (REF) are achieved.

The absence of recognized long-termrenal failure was

notable. However, because of population movement, the

duration of follow-up was inadequate. Although there was

no requirement for immediate long-term dialysis, im-

proved survival may be at the expense of chronic renal

failure, renovascular hypertension, and reduced long-

term survival.

In conclusion, given the circumstances of the study,

acute renal failure complicating severe preeclampsia is arare condition. Intensive hemodynamic and renal inter-

vention in this group of patients was associated with a

good outcome. The management applied appears to be

effective, although comparative data are few and long-

term sequelae are unknown. Future studies should focus

on comparative interventions as well as controlled cohort

outcome studies.

REFERENCES

1. Lindheimer MD, Katz AI, Ganeval E. Acute renal failure inpregnancy. In: Brenner BM, Lazarus JM, editors. Acute renalfailure. 2nd ed. New York: Churchill Livingstone; 1988. p. 597.

2. Madias NE, Donohoe JF, Harrington JT. Post ischaemic acuterenal failure. In: Brenner BM, Lazarus JM, editors. Acute renalfailure. 2nd ed. New York: Churchill Livingstone; 1988. p. 251.

3. Sibai BM, Villar MA, Mabie M. Acute renal failure in hyper-tensive disorders of pregnancy. Am J Obstet Gynecol 1990;162:777-83.

4. Sibai BM. Eclampsia: maternal-perinatal outcome in 254 consec-utive cases. Am J Obstet Gynecol 1990;163:1049-54.

5. Weinstein L. Syndrome of hemolysis, elevated liver enzymes, andlow platelet count: a severe consequence of hypertension inpregnancy. Am J Obstet Gynecol 1982;142:159-67.

6. Anthony J, Johanson R, Dommisse J. Critical care managementof severe preeclampsia. Fetal Matern Med Rev1994;6:21929.

7. Gilbert WM. Towner DR, Field NT, Anthony J. The safety andutility of pulmonary artery catheterization in severe preeclamp-sia and eclampsia. Am J Obstet Gynecol 2000;182:1397-403.

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