BRIEF REPORT

Rh prophylaxis

Underutilization of Rh Prophylaxis in the

Emergency Department: A Retrospective Survey

Front the Emergency Medicine

Residency Program* and the

Department of Emergency

Medicine, t Foothills Hospital,

Calgar), Alberta, Canada.

Submitted for publication July ] 7,

1991. Accepted for publication

September 10, 1991.

Jeff Grant, MD*

Mark Hyslop, MD, FRCPC t Study objective: To determine the practice of emergency physicians with regard to the issue of Rh isoimmunization.

Design: A retrospective chart review.

Setting: A university-affiliated tertiary care hospital emergency department.

Type of par t ic ipants : Pregnant women presenting with a risk factor for Rh sensitization.

Measurements and main results: One hundred thirty-eight patient encounters were analyzed descriptively as to whether they were candidates for Rh immune prophylaxis, and if so, whether it was given. Most (68%) were hospitalized. Of those, all were Rh typed, but two patients were not given Rh immune globulin (RhlG) when indicated. Of those discharged from the ED, most (86%) were not Rh typed, and none was administered RhlG.

Conclusion: This study demonstrates a need for increased attention to the potential for Rh isoimmunization in patients presenting to the ED. [Grant J, Hyslop M: Underutilization of Rh prophylaxis in the emergency department: A retrospective survey. Ann Emerg Med February 1991 ;21:181-183.]

INTRODUCTION

Rhesus (Rh) isoimmunization occurring before delivery contin- ues to affect a significant number of Rh-negative women) -3 This

occurs despite efforts to reduce this number by improved Rh

immune globulin (RhIG) prophylaxis for women who have events

during their pregnancies that place them at increased risk. These

events include spontaneous or elective abortions, ectopic preg-

nancies, antepartum hemorrhage, and other causes of potential fetomaternal transplacental hemorrhage such as trauma. 1'2'z~

Our study was designed to examine the practice of emergency

physicians with regard to the issue of Rh isoimmunization. I~

184/181 ANNALS OF EMERGENCY MEDICINE 21:2 FEBRUARY1992

Rh PROPHYLAXIS

Grant & Hyslop

METHODS AND MATERIALS A retrospective survey of

patients presenting to the

emergency department of a

large university-affiliated

tertiary care hospital was

undertaken. The survey

encompassed the three-month

period from January 1, 1990,

through March 31, 1990, and

included all patients seen

initially in the ED and dis-

charged with a diagnosis of

pregnancy-associated bleed-

ing, eetopic pregnancy, or

pregnancy associated with

abdominal trauma. Each

patient's age, gravidity, blood

type, history of previous Rh

isoimmunization, administra-

tion of RhIG, and immediate

disposition were extracted

from each chart by one

investigator.

RESULTS

One hundred thirty-eight

patient encounters involving

128 patients were analyzed

(ten patients were seen twice).

Maternal ages ranged from 15

to 46 years (mean age, 28

years), and gravidity ranged

from 1 to 10 (mean gravidity,

2.6). No patient had a docu-

mented history of previous

isoimmunization. The spec-

trum of discharge diagnoses is

given (Table).

The majority of patients

(68%) were admitted to the

hospital from the ED and dis-

charged with diagnoses of

incomplete abortions (after

dilation and curettage) or

ectopic pregnancies (after

surgery). Of those seen in and

discharged from the ED,

almost all were considered to

have threatened abortions.

The one patient with ectopic

pregnancy was discharged

against medical advice. No

patient had a discharge diag-

nosis of abdominal trauma

and pregnancy.

Rh status was noted on the

chart for all admitted patients

(confirmed by blood type and

antibody screen) but only six

of 44 discharged patients

(14%), leaving 38 of 44 (86%)

who had no notation of Rh

status documented.

Several points are worthy of

mention. In the group admit-

ted to hospital, 14 of 94 were

Table.

Spectrum offinal diagnoses from 138 patient encounters

Discharge No, of Patients No. of Patients Diagnosis Admitted Discharged Threatened abortion 3 38

Incomplete abortion 52 1

Inevitable abortion 1 1

Missed abortion 4 0

Blighted ovum 1 0

Intrauterine death I 0

Ectopic pregnancy 26 1

Spontaneous abortion 2 O

Completed abortion 4 3

Total 94 44

Rh negative (15%), but two

of 14 (14%) were not given

RhIG. One had a postsurgical

eetopic pregnancy, and the

other had a primigravid

incomplete abortion after

dilation and curettage.

Neither was previously sen-

sitized, nor was the father's

blood type noted. No test to

detect fetomaternal transfu-

sion (Kleihaur-Betke) was

performed.

Of the 44 patients

discharged from the ED, only

one was noted to be Rh nega-

tive but not given RhIG.

Discharge diagnosis was of a

threatened abortion; no formal

type and antibody screen

were done; no Kleihaur-Betke

testing was done; and there

was no specific early follow-

up advised. The father's blood

type was documented as Rh

positive. Of the remaining 38

patient encounters who had

no documented Rh type ("Rh

unknown"), 16 of 38 (42%)

had blood type documented

on readily available old charts

(requested in only five eases).

Only ten of 38 patients (26%)

had a specific early follow-up

plan with a physieian. No

patient was offered or given

RhIG in the ED.

DISCUSSION In the past 25 years, no pro-

gram has been more success-

ful in the improvement of fetal

outcome than that of preven-

tion of Rh isoimmunization in

Rh-negative women bearing

Rh-positive children) '2

Administration of RhlG in the

postpartum period alone has

been shown to decrease the

likelihood of maternal anti-D

sensitization by a factor of 10,

fiom approximately I6% to

1.5% to 2.0%. 1-3 It appears

that most of the remaining

1.5% to 2.0% are sensitized

before delivery and that the

incidence of sensitization is

increased by certain antepar-

turn events that may involve

or precipitate fetomaternal

transplacental hemorrhage. 1 4

These events include any

vaginal bleeding in pregnan-

cy, such as threatened abor-

tions, as well as ectopic preg-

nancies and some cases of

abdominal trauma) '2'¢

Current recommendations for

the administration of Rh pro-

phylaxis include the above

events in any Rh-negative

individual who may be carry-

ing an Rh-positive fetus. 1-2

The administration of the

RhIG appears to convey little

risk, 1'2 with the potential to

avoid some of the complica-

tions associated with subse-

quent pregnancies in an Rh-

sensitized mother carrying

another Rh-positive fetus,

such as repeated amniocente-

sis, intrauterine transfusions,

and fetal death. 1'2

Previous authors have

expressed concern about the

lack of emphasis on the

potential for Rh isoimmuniza-

tion in patients with threat-

ened abortions. 5'6 The pres-

ent study appears to confirm

this. Although the numbers

are small, the vast

FEBRUARY1992 21:2 ANNALS 0F EMERGENCY MEDICINE 1 8 2 / 1 0 5

Rh P R O P H Y L A X I S

Grant & Hyslop

majority of patients seen in and discharged from the ED

had no documentation of Rh

status. Many had blood types

noted on charts from previous

admissions that were readily

available on request. In addi-

tion, most discharges did not

include specific early follow-

up plans (which would give a further chance for considera-

tion of Rh prophylaxis).

We recommend that emer-

gency physicians carefully

consider the potential for Rh

isoimmunization in their preg-

nant patients, with considera-

tion of RhIG prophylaxis for

those deemed at risk. The

dose of RhlG required will

vary depending on circum-

stances; 50 pg IM is consid- ered adequate for first-

trimester bleeding with 300

pg IM for later bleeding, and

dosing for abdominal trauma

should be based on results of

screening for transplacental

hemorrhage (Kleihaur-Betke

test for fetal red blood cells in the maternal circulation))' 2,7

Antibody screening should

always be performed so that

RhIG is not wasted when the mother is already sensitized, s'9

It is also important that the

blood bank and patient's

physician be notified of RhlG

administration, as this will be

useful information in the

interpretation of subsequent

tests for development of Rh

sensitization) °

C O N C L U S I O N

A large proportion of patients

at risk for Rh sensitization are

seen only by emergency

physicians. Of those, most are

managed without any atten-

tion to Rh status. Maternal Rh

type should be documented

in the ED as automatically as

tetanus immunization

status. •

The authors acknowledge the invaluable assistance

provided by the Health

Records Department,

Foothills Hospital; by Dr J

Jarrell, who provided

manuscript review; and by Ms

Lynn Soum, who prepared the

manuscript.

R E F E R E N C E S 1. Bowman JM: Controversies in Rh prophylaxis. Am J Obstet Gynecol 1985;151:289-294. 2. McMaster Conference on Prevention of Rh Immunization. Vox Sang 1977;36:50-64. 3. Mollison PL: Clinical aspects of Rh immunization. Am J Clin Pathol 1978;60:287-391. 4. Jorgensen J: Feto-maternal bleeding. Acta Obstet Gynecol Scand 1977;96:487-490. 5. Dayton VD, Anderson DS, Corsson JT, et ah A case of Rh isoimmunization: Should threatened first-trimester abortion be an indication for Bh immune globulin prophy[axis? Am J Obstet Gynecol 1990;163:63-64. 6. Huchcroft S, Gunton P, Bowen T: Compliance with postpartum Rh isoim- munization prophylaxis in Alberta. Can Med Assoc J 1985;133:871-875. 7. Rose PG, Strohm PL, Zuspan FP: Fetomaternal hemorrhage following trauma. Am J Obstet Gyneco11985;153:844-84 7. 8. Bowman JM, Pollock JM: Reversal of Bh alloimmunizatian - - Fact or fancy? Vox Sang 1984; 47:209 -215. 9. de Silva M, Contreras M, Mollison PL: Failure of passively administered anti-Rh to prevent secondary Rh responses. VoxSang 1985;48:178-180. 10. Pisciotto P, Gorbants I, Sundra M: Antenatal Rh immunoglobulin - - Help or hindrance? Transfusion 1985;25:88.

Address for reprints: Jeff Grant, MD,

Department of Emergency Medicine,

FoothiLls Hospital C231, 1403-29

Street NW, Calgary, Alberta, Canada

T2N 2T9,

1 0 6 / 1 8 3 ANNALSDF EMERGENOYMEDICINE 21:2 FEBRUARY1992