High risk antenatal hospitalization

Km. J. Gynaecol. Obstet., 1982, 20: 475-480 International Federation of Gynaecology & Obstetrics

BIGII RISK ANTENATAL HOSPITALIZATION

MARK PHILLIPPE,

FREDERIC

D. FRIGOLETTO,

PAUL VON OEYEN,

DAVID ACKER

Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Medical School, 75 Francis St., Boston, MA 02115, USA (Received (Accepted

and JOHN L. KITZMILLER

Brigham and Women’s Hospital and the Harvard

February 23rd, 1982) April 14th, 1982)

resulting in an overall perinatal survival rate of 95%.

Abstract Phillippe M, Frigoletto FD, van Oeyen P, Acker D, Kitzmiller JL (Division of MaternalFetal Medicine, Dept of Obstetrics and Gynecology, Brigham and Women S Hospital and the Harvard Medical School, 75 Francis St., Boston, MA 02115, USA). High risk antenatal hospitalization. Int J Gynaecol Obstet 20: 475-480, 1982 High risk, antenatal units have been established to provide highly sophisticated obstetric care for women with complications of pregnancy. In an effort to more precisely define the patients requiring this care, and to begin to document the benefits ofantenatal hospitalization, a 2-year prospective evaluation of the Antenatal Unit (AU) at the Brigham and Women’s Hospital was performed. Between July I, 1978 and June 30, 1980, 1488 consecutive patients were admitted to the AU. Demographic data, antenatal hospitalization time, hospitalization outcome, and delivery data were determined for these patients. Diabetes mellitus, premature labor, hypertensive disorders, premature rupture of the membranes, and late pregnancy bleeding disorders resulted in over 60% of the admissions. Follow-up data demonstrated that among these 1488 patients admitted to the AU, there occurred 32 stillbirths (21.511 OOO),SOneonatal deaths (33.6/1000), and no maternal deaths. This study demonstrated that a broad spectrum of medical, surgical, and obstetric complications necessitate antenatal hospitalization, 0020-7292/82/0000-0000/$02.75 0 1982 International Federation Printed and Published in Ireland

Key words: High risk; Antenatal units; Obstetric care; Complications in pregnancy; Document benefits of antenatal hospitalization; Perinatal survival rate Introduction During the last decade, the high risk antenatal obstetric unit has become a distinct entity in Level II and Level III hospitals [ 11. Such units have been established to provide intensive evaluation and care for those women with identifiable obstetric, medical, and surgical conditions which threaten obstetric outcome [ 2-41. At the Brigham and Women’s Hospital (BWH) (formerly the Boston Hospital for Women) such a unit was established in 1974. Previous publications have described demographic and outcome data for specific subgroups of antenatal patients, particularly transfer patients [4,5 $1. However, to date there are no large prospective studies evaluating such data for all patients admitted for antenatal care. In an effort to define the type of patients requiring this care, and to more clearly establish the benefits of antenatal hospitalization, a prospective evaluation of the Antenatal Unit (AU) at the BWH was performed between July 1,1978 and June 30, 1980. During the period of this study, 12,407 women delivered at the BWH, of which 1488 Int J Gynaecol Obstet 20

of Gynaecology

& Obstetrics

416

Phillippe et al.

high risk patients not requiring immediate delivery were admitted to the AU. Methods Data on all patients admitted to the antenatal high risk unit was prospectively obtained during the time of hospitalization. Demographic data including maternal age. gravidity, parity and gestational age on admission was recorded on each patient. Hospital days on the AU was defined as days from admission until either delivery or discharge undelivered. Health care provider was categorized as private physician, or clinic/faculty medical staff. All outcomes were recorded as either delivered or discharged undelivered.Ofthosepatientsdelivered, route of delivery (i.e. vaginal vs. cesarean section) was noted. The major admission diagnosis was recorded for each patient, then categorized by order of frequency into: Diabetes Mellitus, Premature Labor, Hypersensitive Disorder, Premature Rupture of Membranes (PROM), Late Pregnancy Bleeding Disorders, Incompetent Cervix, Isoimmunization, or other medical-surgicalobstetric disorders. No attempt is made in this study to define admission criteria other than major diagnosis, patients care protocols, or clinical indications for delivery or discharge undelivered. Patient management for the above criteria was determined by the individual physicians admitting patients to the AU according to their clinical judgement and the specifics of the clinical situation. The outcomes of all the patients hospitalized on the antenatal unit delivering at the BWH was established as either liveborn, stillborn, or neonatal death. Confirmation of all stillbirths and neonatal deaths was made by an analysis of neonatal and pathology records. The perinatal deaths were then categorized into groups by the major obstetric diagnosis contributing to the stillbirth or delivery of an infant who subsequently died in the intensive care nursery. The total uncorrected stillbirth, neonatal death, and perinatal mortality rates for this study were Int J Gynaecol Obstet 20

calculated by dividing the number of deaths in each category by the total number of patients admitted to the antenatal unit. The statistical comparisons were made where appropriate by the two-tailed t-test. Results During the period of this study there were 12,407 deliveries of 12,590 infants at the BWH. The uncorrected perinatal death rate was 24.6/ 1000; defined as any death occurring between 20 weeks of gestation and the 28th postpartum day. Among the stillbirths 16.2% were associated with (11.9/ 1000), major congenital anomalies, 31.8% were of unknown etiology, and 52% were associated with identifiable complications (Table I). 78.4% of the total number of stillbirths and 68.4% of the neonatal deaths occurred in patients who did not receive antenatal hospitalization . During this study, there were 1625 admissions of 1488 patients to the antenatal unit; a readmission rate of 9.2%. Private patients

Table 1. Total number of stillbirths with identifiable associated medical complications from the total 12,407 deliveries between July 1, 1978 and June 30, 1980. Associated complication

Number

Percent

Premature labor Cord accident Infection Abruptio placenta Isoimmunization Diabetes Mellitus Incompetent cervix Twin-twin transfusion syndrome Premature ruptured membranes Hypertensive disorders Postmaturity Birth asphyxia Systemic lupus erythematosus Non-immune hydrops Maternal cardiomyopathy

11 11 9 9 8 8 5 4 3 2 2 2 1 1 1 -

14.3 14.3 11.7 11.7 10.4 10.4 6.5 5.2 3.9 2.6 2.6 2.6 1.3 1.3 1.3

TOTAL ~___

77

High risk antenatal hospitalization 477 Major admission diagnoses for 1,488 Table II. admitted to the antenatal high risk obstetric unit.

patients

Admission diagnosis ~~

No. of admissions

Percentsa

Diabetes Mellitus Premature Labor Hypertensive disorder PROM Third trimester bleeding Incompetent cervix Isoimmunization Other medic;l/surgical/ obstetric

299 293 209 196 156 88 62

18.4 18.0 12.9 12.1 9.6 5.4 3.8

517

31.8

a Nore: >lOO% because 12% of patients had more than one major admission diagnosis. b Includes: hyperemesis, thrombophlebitis, pyelonephritis, multiple gestations, hepatitis, idiopathic intrauterine growth retardation, sickle cell crisis, appendicitis, urinary calculi, sarcoidosis, uterine myomata degeneration, asthma, narcotic addiction, seizure disorders, postmaturity, congenital heart disease, VonRecklinghausen’s disease, familial periodic paralysis, tuberculosis, cystic fibrosis, ovarian neoplasms, polyhydramnios, incarcerated uterus, biliary cirrhosis, motor vehicle trauma, rheumatic heart disease, cholestatic jaundice, renal failure, paraplegia, and systemic lupus erythematosus.

accounted for 41.4% of the admissions and 58.6% were clinic/faculty staff patients. Diabetes mellitus was the largest admission diagnosis category at 18.4%; 91% of these patients were insulin-dependent diabetics. Other major admission categories included premature labor ( 18 .O%), hypertensive disTable

III.

Demographic

Data

data

obtained

during

year

orders (12.9%), premature rupture of the membranes (PROM) ( 12.1%), late pregnancy bleeding (9.6%), cervical incompetence (5.4%) and isoimmunization (3.8%). Other less common obstetric, medical, and surgical conditions made up an additional 3 1.8% of the total number of admissions, as noted in Table II. More than one major admission diagnosis occurred in 12% of the patients. Complete demographic data from the first year of the study demonstrated that among 790 admissions, the mean maternal age was 28.3 ? 5.5 years (? S.D.), gravidity 3 f 2.0, parity 1 f 1.7, and hospital days on the high risk unit 7.1 + 10.1 days (Table III). Among these 790 admissions, 44% eventuated in delivery at some point during the original hospital admission. The remaining 56% were treated and discharged undelivered, to be admitted at some later time for delivery. These data varied somewhat depending on admission diagnosis. The mean gestational age was significantly (P < 0.01) further advanced for the diabetic (33.4 f 5.9 weeks) and hypertensive (34.9 f 4.7 weeks) women. The maternal age (25.0 f 6.1 years) and gravidity (2 f 1.5) were significantly lower (P < 0.01) among the women with premature labor. The total hospital days on the antenatal unit was quite variable, being the longest among women with late pregnancy bleeding disorders (12.1 + 14.7 days). Over

1 of this study

on admissions

to the antenatal

high risk obstetric

unit.

Overall

DM

Prem. L

HBP

PROM

Bleeding

admission (weeks) Maternal age

30.9 ?; 7.5

33.4 * 5.9a

30.1 + 4.0

34.9 + 4.7

30.7 +_ 2.8

31.4 f

(years) Gravidity Parity Hospital days on the

28.3 + 5.5 3+ 2.0 l? 1.7

27.8 f 5.4 3 + 2.0 1 f 1.7

25.0 ? 6.1a 2 + 1sa 1 + 1.0

28.1 + 6.1 3 +- 2.2 1 + 1.8

27.4 t 3+ l+

28.5 + 7.0 3 + 3.7 1 + 3.1

7.1 + 10.1

10.7 r 8.6a

6.1 f 8.0

7.7 r 7.0

Gestational

age on

antenatal unit Number delivered (percentage)

44%

Data in mean f 1 SD.; aP < 0.01, mature Labor) HBP, (Hypertensive Bleeding Disorders).

75%a

bP < 0.05 compared Disorders),

PROM

35%

80%a

5.7 2.4 1.6

9.8 f 13.4 88%a

3.6

12.1 i 14.7b 35%

to the overall high risk population. DM (Diabetes Mellitus), Prem. L (Pre(Premature Rupture of the Membranes) and Bleeding (Late Pregnancy

Int J Gynaecol Obstet 20

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Phillippe et al.

Table IV. Stillbirths occurring among 1488 women hospitalized on the antenatal high risk obstetric unit.

Table V. Neonatal deaths occurring among 1488 patients hospitalized on the antenatal high risk obstetric unit.

Obstetric diagnosis

Range of gestational ages (weeks)

Number

Obstetric diagnosis

Range of gestational ages (weeks)

Number

Isoimmunization Twin-twin transfusion syndrome Diabetes mellitus Abruptio placenta Premature labor Hypertension Cord accident PROM Chorioamnionitis Incompetent cervix Lupus Viral infection Non-immune hydrops

23-33 23-24 22-35 23-21 20-23 25,38 26,34 24,32 21,29 21,23 24 33 24

I 3 3 3 3 2 2 2 2 2

PROMa Premature labor Isoimmunization Hypertension Congenital anomalies (including 1 IDM)b Twin-twin transfusion syndrome Abruptio placenta Incompetent cervix Placenta previa Twin cord accident Non-immune hydrops

23-32 23-26 24-31 29-35

14 10 5 4

32-40 23-28 23-28 21-23 21,24 26 24

4 3 3 3 2 1 1

-

TOTAL

TOTAL

50

32

a Premature Rupture of the Membranes b IDM (Infant of a Diabetic Mother).

75% of the admissions for diabetes, hypertension, and PROM resulted in delivery during the original admission. Among the women requiring delivery 48% were delivered per vagina, whereas 52% required delivery by cesarean section. There were 32 stillbirths (Table IV) among the total 1488 women admitted to the AU (2 1 S/l 000). Among the stillbirths, seven occurred in women with isoimmunization and severe erythroblastosis fetalis between 23 weeks and 33 weeks of gestation. Two very immature fetuses were stillborn to women with incompetent cervix. Three stillbirths occurred in each group associated with diabetes mellitus, twin-twin transfusion syndrome, abruptio placenta, and premature labor. Hypertensive disorders, cord accident, chorioamnionitis and PROM contributed two stillbirths in each category. A single stillborn infant each occurred in a woman with a hydropic fetus, a patient with systemic lupus erythematosus, and a woman with a systemic viral infection. Fifty neonatal deaths (33.6/ 1000) occurred among the patients hospitalized on the AU Int J Gynaecol Obstet 20

as noted in Table V. Premature labor, resulting in 10 deaths, and premature rupture of the membranes, resulting in 14 deaths, contributed the largest number of these infants. Five neonates between 24 weeks and 31 weeks of gestation died as complications of isoimmunization and erythroblastosis fetalis. Women with hypertensive disorders, incompetent cervix, twin-twin transabruptio placenta, and fusion syndrome, placenta previa contributed a total of 15 of the neonatal deaths; common to all of these infants was marked prematurity. Four of the neonatal deaths were associated with major congenital anomalies, one of which occurred in an infant of a diabetic mother. Nonimmune hydrops and asphyxia secondary to twin cord entanglement contributed the other two neonatal deaths. The combination of stillbirths and neonatal deaths among these 1488 antenatal patients gave an uncorrected high risk perinatal mortality rate of 55.1 /lOOO. This figure is not corrected for patients transferred to the BWH with an intrauterine demise. congenital anomalies incompatible with life. or

High risk antenatal hospitalization

for marked prematurity (i.e. gestational age 5 28 weeks). The perinatal mortality rate after correction for these factors was 14/l 000. There were no maternal deaths among the high risk pregnant women hospitalized on the AU during the period of this study. Except for an increased incidence of cesarean section, no other major maternal morbidity was observed in these women specifically related to antenatal hospitalizations. Discussion The purpose of the Level II and Level III obstetric hospital is to provide medical care for those pregnant women with identifiable complications that have the potential of serious maternal and/or infant morbidity and mortality [ I-41. The antenatal, high risk obstetric unit is intended to provide a designated area within the hospital for pregnant women to receive the kinds of sophisticated and intensive care required by the high risk pregnancy [3,5 I. A team consisting of staff perinatologists, fellows, residents, nurses, nutritionists, and social workers is necessary to provide the kind of 24 h, day-today evaluation and care these patients require. Additional support in the form of a gestational endocrinology laboratory, an ultrasound facility, and an antenatal fetal monitoring unit is likewise essential in the care of these pregnant women. The costs of this type of sophisticated care and prolonged hospitalization is obviously high, anb must be balanced against the benefits of such care. This prospective evaluation of our experience on an antenatal, high risk obstetric unit was begun to attempt to more precisely define the kinds of patients requiring this care, and to begin to assess the potential benefits by analysis of the maternal and fetal outcomes. Walters et al. [4] described a 5-year perinatal unit experience ending in 1971; in which they observed that the number of patients needing such special care increased from 4.66% to 13.34% of their total deliveries. During the 2-year period of our study, 12% of

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the patients delivered at the BWH required antenatal hospitalization. The age, gravidity, and parity of these women was similar to that reported in previous series [ 6,7 1, and not unlike that of non-high risk population delivered at the BWH. Analysis of our data demonstrated that 58% of these patients received care on the clinic/faculty staff service, and the remainder were managed by their private obstetrician with variable degrees of consultation with the perinatal team. Approximately 15% of the antenatal patients in this report were transferred to the BWH from other hospitals; in contrast to previous publications [4,5 ,S] this study was not designed to evaluate these patients separately. Knuppel et al. [ 51 in 1979 observed that premature rupture of the membranes, premature labor, and placental bleeding were the admission diagnosis for 73% of their patients. DeGeorge [7] in 1971 found that poor previous obstetric history, hypertensive disorders, diabetes mellitus, maternal cardiac disease and Rh sensitization were the most common diagnoses in their patients. In a series of 397 antenatal patients published by Modanlou et al. [8], in 1980, diabetes mellitus, premature labor, premature rupture of membranes, hypertensive disorders, and third trimester bleeding disorders were the most frequent diagnoses. The data from our 1488 antenatal patients demonstrate that diabetes mellitus, premature labor, hypertensive disorders, premature rupture of the membranes, and late pregnancy bleeding disorders accounted for two-thirds of the admission diagnosis. However, equally important is the fact that a broad range of relatively uncommon medical, surgical, and obstetric complications resulted in the remaining 30% of the admissions. This observation reinforces the need for collaborative management by obstetricians, neonatologists, anesthesiologists, radiologists; and multiple other consultants as discussed in the perinatal experience described by Borkowf [ 91. The average hospitalization time on our Int J Gynaecol Obstet 20

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AU was 7 days; however the range was from less than 1 day to a maximum of 61 days. This does not include post-partum hospitalization time which varied between 3 and 7 days. In the report by Knuppel [ 51, the mean total maternal hospital stay was 11.2 days. In our series, over half of the women admitted to the AU were able to be discharged undelivered. This was particularly true for women with premature labor and bleeding disorders, excluding placenta previa. The risk of prematurity remains a major component of perinatal care; the mean gestational age of our patients at the time of admission to the AU was 30.9 weeks. This is in agreement with the gestational age of 3 1.4 weeks described by Knuppel [ 51, and the mean gestational age at delivery of 3 1.8 weeks among the antenatal patients described by Modanlou [83. With the use of tocolytic agents such as Terbutaline, we and others [ 10,111 observed that 65% or more women with only premature labor were able to be discharged undelivered. Whereas we observed that patients with other types of pregnancy complications now contribute to the delivery of premature infants. The outcomes of these high risk pregnancies resulted in about 95% of the women hospitalized on the unit delivering infants who survived the neonatal period and were discharged home alive. The overall uncorrected perinatal mortality was 55.1/l 000 high risk, antenatal patients. This rate is as expected higher than the overall perinatal mortality rate of approximately 20/l 000 in the United States; and consistent with the antenatal unit, perinatal mortality rates of 93.1/1000 reported by Modanlou [8 I and 118/ 1000 reported by Knuppel [5]. None of these studies, including our own, have been randomized observations with a control group of non-hospitalized, similarly high risk obstetric patients; therefore the benefit of this expensive, highly sophisticated obstetric management remains unproven with statistic certainty

.

In conclusion, in this report we have attempted to define the patient characteristics and medical disorders that resulted in Int J Gymecol Obstet 20

the need for antenatal hospitalization. We have also attempted to measure benefit in the form of uncorrected perinatal mortality in this group of 1488 high risk, antenatal patients. There is, however, need in the future to determine additional endpoints including prematurity rate reductions, neonatal morbidity rates, and perinatal care cost reductions. These additional endpoints along with a determination of the exact cost of antenatal hospitalization will in the future need to be answered as this care becomes more established as standard medical practice. References 1 Ryan GM, Pettigrew AH, Fogerty S et al.: Regionalizing perinatal health services in Massachusetts. N Engl J Med 296: 228,191l. Gold EM: Obstetric aspects of perinatology. Clin Perinatoll: 19,1914. Resnik R: Principles of organization of an obstetrical unit from scratch. Clin Perinato13: 323, 1916. Walters JH, Effer S, Ramprakash H et al.: Experience with an obstetrical and neonatal intensive care unit. Am J Obstet Gynecol115: 301,1913. 5 Knuppel RA, Cetrulo CL, Ingardia CJ et al.: Experience of a Massachusetts perinatal center. N Engl J Med 300: 560,1919. 6 Thompson HE, McFee JG, Haverkamp AD, Longwell FH: Facors contributing to improved maternal care and fetal outcome in a medium-sized city - county hospital. Am J Obstet Gynecol116: 229,1913. 1 DeGeorge FV, Nesbitt REL, Aubry RH: High risk obstetrics. Am J Obstet Gynecol III: 650, 1911. 8 Mondanlou DH, Dorchester W, Freeman RK, Rommal C: Perinatal transport to a regional perinatal center in a metropolitan area: Maternal versus neonatal transport. Am J Obstet Gynecol138: 1151,198O. 9 Borkowf HI, Grausz JP, Delfs E: The effect of a perinatal center on perinatal mortality. Obstet Gynecol 53: 633, 1979. 10 Ingemarsson I: Effect of Terbutaline on premature labor. Am J Obstet Gynecol125: 520,1976. 11 Ryden G: The effect of Salbutamol and Terbutaline in the management of premature labour. Acta Obstet Gynecol Stand 52: 293,191l. Address for reprints: Mark Phillippe, M.D. Dept of Obstetrics and Gynecology Brigham and Women’s Hospital and the Harvard Medical School 15 Francis St. Boston, MA 02 115 USA