Note: hormonal emergency contraception is less effective if the patient is already taking e nzyme-inducing drugs: take specialist advice. Options include an IUCD or i dose of levonorg estrel to 3mg (see BNF) . 569 CONTRACEPTIVE PROBLEMS IUCD This may be useful for patients unable to take the OCP (eg previous pul- monary embolu s), patients who wish to use IUCD long-term and for those presenting between 3 and 5 days a fter unprotected intercourse. Failure is very rare. Insertion is uncomfortable and requires appropriate training: refer to the gynecology team. Note that IUCD should not be used with a history of recent PID. Prescribing to patients on OCP Both progestogen-only oral contraceptives and (combined) OCP may fail if enzyme inducing drugs are prescribed. These include: rifampicin, rifab- utin, carbamazepine, phenytoin, topiramate, griseofulvin, phenobarbital, and primidone. Patients need alternative or additional contraception if these drugs are started. Rifampicin and rif abutin are such potent enzyme- inducing drugs that contraceptive precautions should continu e for at least 4 weeks, even after a short course of rifabutin or rifampicin (as used for p rophylaxis of meningococcal infection). Antibiotics and the OCP (refer to BNF) Broad spectrum antibiotics commonly prescribed in th e ED may inter- fere with estrogen absorption and cause contraceptive failure. Before presc ribing antibiotics to a female of childbearing age, ask whether she is taking the OCP. Advi se additional contraceptive precautions (eg condoms), whilst taking the antibiotics and for 7 days after. If these 7 days run beyond the end of a packet, start the next packet immedi ately without a break. Document in the notes that this advice has been given. 570 CHAPTER 13 Obstetrics and gynecology Genital injury and assault The history may be misleading. Combine a high index of suspicion with a full examination to exclude signi \201 cant injury. Blunt genital injury may result from falls astride. Most resultant vulval haematomas settle with rest and ice packs. Refer very large haematomas for evacuation in theater. Penetrating injury may follow assault, FB insertion, or migration/ perforation of an IUCD ( particularly during insertion). Abdominal pain associated with a vaginal wound may be due t o peritonitis. Obtain venous access, erect chest X-ray (for free gas), abdominal X-ray (for FB), group and save, give antibiotics, and refer. Refer other vaginal tears without perito nitis for exploration and repair. Rape and sexual assault Rape is de \201 ned in the UK as vulval penetration by the penis w ithout consent. Rape and other forms of sexual assault are believed to be grossly under-rep orted. Those who do report it have special requirements. Privacy is essential: ideally, a s pecially equipped room will be devoted to assess- ment of women who have been sexually assa ulted. Ensure that a female member of staff is present throughout. Documentation must be le gible and meticulous. An established protocol will allow prompt and thorough investigation and treatment. Usually, ED staff provide emergency treat- ment and resuscitation, but most of the other aspects, including collection of forensic evidence are dealed with by a forens ic physician (police surgeon), ideally in a specialized Sexual Assault Referral Center. Som etimes, women initially decline police involvement: full assessment and documentation may p rove useful if there is a change of mind. First exclude life-threatening or serious injuries. History Establish the type, date, time, and place of the assault. Ask what occurred (vagina l/anal penetration, oral sexual activity, other injuries). Ask about contraception use and enquire about LMP. Find out what is known about the assailant(s), and their risk of HIV and hepatitis B. In particular are they injecting drug users, do they originate from sub-Sahar an Africa, are they homosexual? Examination Look for evidence of vaginal, oral or anal injury (the forensic physician will take swabs). Record any other injuries, such as bites, bruising, or skin wounds (photograph s of non-genital injuries may be useful \200\224 taken by the police with the patient \200 \231s consent). Investigation Obtain written informed consent. The police will be keen to retain clothing, loose hairs, \201 ngernail clippings, and tampons for evidence. Similarly, the forensic p hysician will take appropriate swabs (vaginal, oral, anal). Perform a pregnancy test. Take and store blood for future DNA and viral testing. 571 GENITAL INJURY AND ASSAULT Treatment \200 Resuscitate as necessary. Refer urgently the 1 % of patients who have sig ni \201 cant genital injuries (eg vaginal tears) requiring surgical intervention. Consider the need for post-coital contraception (see b p.568). \200 If the patient is not immunized, give hepatitis B immunoglobulin and start an active immunization course. Assess the risk of HIV. If the assailant is known to have HIV or is from an at risk group, discuss the risk of disease transmission with the patient. Involve a local expert such as a virologist or infectious disease specialist prior to offering HIV prophylaxis ( b Needlest ick injury, p.418). Assess tetanus vaccine requirements. \200 Arrange follow-up to exclude STD. Consider anti biotic prophylaxis against STD if the patient is unlikely to attend follow-up: liaise with the GU team. Provide initial counseling and ensure a safe place to stay (a social worker may arrange this). Arrange future counseling. Inform the patient about independent local advice available (eg Rape Crisis Center). Ascertain from the patient if she wishes her GP to be informed. Telephone advice Women may telephone the ED for advice after being raped. Advise them to in form the police immediately, and then attend the police station or the ED. Discourage them from washing, changing clothes, using a toilet or brushing teeth before being examined. 572 CHAPTER 13 Obstetrics and gynecology Gynecological pain Gynecological disorders presenting to the ED with abdominal pain may be dif \201 cult to distinguish from other disorders. Obtain a full history of the pain: sudd en onset of severe colicky pain follows ovarian torsion and acute vascular events; more ins idious onset and continuous pain occur in infection and in \202 ammation. Radiation of the pain into the back or legs sug- gests gynecological origin. Other clues in the history inc lude co-existing symptoms of vaginal discharge, vaginal bleeding, or missed last menstrual period (LMP). Abdominal and pelvic pain in early pregnancy may be due to ectopic pregnancy or threatened abortion ( b p.584): both occur in patients who do not realize that they are pregnant or wh o deny the possibility of pregnancy due to embarrassment. Pain related to the menstrual cycle Consider \201 rst: could any associated vaginal bleed ing be from ectopic pregnancy or threatened abortion? Physiological dysmenorrhoea Pain regularly preceding menstruation and peaking on the \201 rst day of a period may be physiological. Suggest NSAID and refer to the GP. Endometriosis Growth of functional endometrial tissue in the pelvis outside the uterus may produce cysts and adhesions. Patients often present age 8 30 years with dysmenorrhoea and m enstrual problems, infertility and dyspareunia. Symptoms are usually chronic and recurrent in a cyclical fashion, and are appropriately followed up by the GP. Occasionally, an endome trial cyst may rupture and bleed severely into the pelvis, presenting in similar fashion to ruptured ectopic pregnancy. Resuscitate for hypovolaemia and refer urgently. Rupture of a corpus luteum cyst Occurs premenstrually, but may also cause signi \201 cant hemorrhage, requiring resuscitation. Mittelschmerz Mid-cycle extrusion of an ovum from a follicular cyst can cause abdominal pai n, which seldom requires admission or investigation. Uterine problems Perforation is seen especially in the presence of IUCD. Leiomyomas ( \200\230 \201 broids \200\231) may undergo torsion (sudden severe colicky pai n with tender uterus), or may infarct ( \200\230red degeneration \200\231) particularly dur ing pregnancy. Refer such suspected problems for specialist investigation. Ovarian problems Torsion causes sudden onset sharp unilateral pain and usually involves an already enlarged ovary (cyst, neoplasm). Abdominal and per vagina (PV) tenderness may be pr esent. Clinical diagnosis is dif \201 cult: if suspected, refer for USS and/or laparoscopy . Bleeding into an ovarian cyst may present similarly and require investigation. 573 gynecological PAIN Pelvic in \202 ammatory disease This term includes infection which has spread from the cer vix to the uterus (endometritis), Fallopian tubes (salpingitis), ovaries (oophoritis), or a djacent peritoneum (peritonitis). Severity ranges from chronic low grade infection (with re latively mild symptoms) to acute infection (with severe symptoms) which may result in absce ss formation. Causes 90 % are sexually transmitted: sexually active women aged 15 \200\22320 years are at particular risk. Most of the remaining 10 % follow pregnancy terminations or dilatation an d curettage. Organisms Chlamydia trachomatis commonest. Also: Neisseria gonorrhea, Mycoplasma hominis, U reaplasma urealyticum . Features Bilateral lower abdominal tenderness, vaginal discharge, fever > 38 o C, abnormal vaginal bleeding, deep dyspareunia, cervical motion tenderness, and adnexal tenderness all point to PID. Management Resuscitate with IV \202 uids if shocked. Check urinalysis and send high vagin al swab and cervical swab, FBC, ESR. Refer all suspected cases to the gynecologist: even th ough not all will require admission, they will require antibiotics (eg oral o \202 oxacin 400 mg twice daily plus oral metronidazole 400mg twice daily for 14 days) and follow-up. Se quelae Ectopic pregnancy (5 \227 i risk) or infertility, therefore have a low threshold fo r empirical treatment. (See http://www.rcog.org.uk ). 574 CHAPTER 13 Obstetrics and gynecology Vaginal bleeding See b Vaginal bleeding in pregnancy, p.582. Triage ahead patients with sev ere bleeding or evidence of hypovolaemic shock. Resuscitate \201 rst (O 2 , cross-match a nd obtain Rhesus status, start IV \202 uids) and ask questions later. Most patients with vaginal bleeding, however, do not require resuscitation. Take a careful menstrual history a nd ask about associated symptoms. Attempt to assess the amount of bleeding. Interpretation of a patient \200\231s description is notoriously dif \201 cult, but useful pointers are t he presence of clots and the rate of tampon use. Always consider the possibility of pregnan cy: remember that ruptured ectopic pregnancy can present before a period is missed ( b p.58 6). Examine for evidence of hypovolaemia and abdominal masses/tenderness. Depending upon th e circumstances, speculum and bimanual vaginal examinations may be required: local policy w ill determine who should perform this. Menorrhagia Dysfunctional uterine bleeding Heavy and/or irregular periods without obvious p elvic pathology may result from hormonal imbalance. It is particularly common at menarche. Most settle without treatment or with simple measures (eg mefenamic acid 500mg PO tds after food). Refer to the GP, unless the bleeding is very heavy. Uterine leiomyomas ( \201 broids) Often cause menorrhagia. May present with a painful comp lication, such as torsion or infarction. Other causes Endometriosis, PID, IUCD, polyps, vaginal carcinoma, hypothyroidism. Bleeding unrelated to pregnancy or periods Trauma The history may be elusive. Post-operative Signi \201 cant bleeding is a risk of any gynecological operation. Resuscit ate and refer. OCP problems Breakthrough bleeding on the OCP may be due to endometrial hyperplasia. Exclud e treatable vaginal/cervical lesions, arrange a cervical smear and refer to GP. Cervical erosion Replacement of strati \201 ed squamous epithelium by columnar epithelium may produce a mucoid discharge with a small amount of post-coital or intermenstrual bleedin g. The cervix appears red. Obtain a cervical smear and arrange follow-up. Cervical polyp Causes post-coital bleeding. Refer to the gynecologist. Cervical cancer 90 % are squamous carcinoma. Strongly associated with human papilloma virus , some consider it an STD. Suspect in anyone presenting with post-coital or intermenstrual bleeding. Speculum examination reveals nodules, ulcers, or erosions, which may bleed to tou ch. Advanced disease may present with pyometra, ureteric obstruction, rectovaginal \201 s tula. Arrange urgent gynecology follow-up for any patient with an abnormal looking cervix. 575 VAGINAL BLEEDING Uterine carcinoma Mostly adenocarcinoma. Classically presents with heavy and frequent post- menopausal bleeding, but normal examination. Arrange assessment and diagnostic curettage wi th the gynecologist. Other causes Thrombocytopenia, other coagulation disorders and anti- coagulant drugs. 576 CHAPTER 13 Obstetrics and gynecology The pregnant patient Pregnant patients presenting with emergency problems create under- sta ndable anxiety. There are two patients: one may be suffering unseen. Maintaining fetal oxyg enation is crucial: call the obstetrician early. Terminology The 40 weeks of pregnancy are divided into 3 trimesters. Traditionally, prob- lems in the \201 rst trimester are consid ered \200\230gynecological \200\231. \200 Gravidity = total number of pregnancies (eg a woman in \201 rst pregnancy is a \200\230primigravida \200\231). Parity = number of pregnancies after 24 weeks + number before (eg a woman who has had 1 chi ld and 2 spontaneous abortions is described as 1 + 2; gravidity = 3). Abortion is fetal death before 24 wks; stillbirth is fetal death after 24 wks. Progression of pregnancy (see also Fig. 13.1 ) Peristalsis and ciliary action carries the fertilized ov um to the uterus, which it reaches as a blastocyst 8 5 days after ovulation. The blastocyst implants in the endometrium: the inner part forms the embryo, the outer part membranes and placenta. Trophoblastic tissue produces human cho- rionic gonadotrophin (HCG), (peaks in \201 rst trimester) acting on the corpus luteum, (essential until the placenta produces es trogen and progesterone). HCG then d , whereas estrogen and progesterone i . Symptoms of pr egnancy Amenorrhoea, breast tenderness and fullness, polyuria, tiredness, nausea (appear by 8 6 weeks). Vomiting is common, occasionally severe enough to cause dehydration and weight loss ( \200\230hyperemesis gravidarum \200\231). Refer for admission and rehydration. Sign s of pregnancy Not obvious in early pregnancy: uterine enlargement (see opposite), breast c hanges. Pregnancy testing see b p.582. Maternal physiological changes Cardiac output i by 3 0 % , peripheral vascular resistance d : BP (especially diastolic) d slightly. Blood vol i by 30 % , plasma vol i by 45 % , Hb d slightly. Systolic \202 ow murmurs are common. Wate r retention occurs, causing ankle oedema and carpal tunnel syndrome. Ventilation i : the pa tient may feel dyspnoeic. Backache is common. d Lower oesophageal pressure causes heartburn ; d gut motility causes constipation; i venous pressure in pelvis may cause varicose veins and hemorrhoids. Platelets, ESR, cholesterol, \201 brinogen i ; albumin d . See Table 13. 1 for normal values in pregnant and non-pregnant women. Diagnostic imaging in pregnancy Try to avoid X-rays and CT scans. Excessive radiation exposure risks con- genital malformation , growth retardation, and neoplasia. However, do not withhold necessary X-rays in life-thre atening illness. Most head, neck, and extremity X-rays can be obtained without fetal risk b y appropriate lead screening. When requesting X-rays, ensure the radiographer is aware the patient is pregnant. USS has not been shown to have adverse effects. If in doubt, discuss i maging requests with a radiologist. Prescribing in pregnancy and during breast-feeding Cons ult the BNF before prescribing drugs in pregnancy or during breast feeding. The following a re generally considered safe in pregnancy: penicillin, cephalosporins, nystatin, paracetamo l, chlorphenamine, cimetidine. Avoid the following: trimethoprim, tetracyclines, streptomyc in, warfarin, thiazides. 577 THE PREGNANT PATIENT 36 weeks 40 weeks 22 weeks 16 weeks 12 week Fig. 13.1 Uterine size in pregnancy. Table 13.1 Normal values in pregnant and non-pregnant women Value Non-pregnant Pregnant Haematocrit 0.37 \200\2230.47 0.32 \200\2230.41 Hemoglobin (g/dL) 11.5 \200\22316.0 11.0 \200\22315.0 4.0 \200\22311.0 \227 10 9 5.0 \200\22316.0 \227 10 9 White cell count (/L) 150 \200\223400 \227 10 9 134 \200\223400 \227 10 9 Platelets (/L) ESR (mm/hr) (age in years + 10)/2 44 \200\223114 Fibrinogen (g/L) 2 \200\2234 4 \200\2236 Albumin (g/L) 35 \200\22350 28 \200\22340 Urea (mmol/L) 2.5 \200\2236.7 1.6 \200\2236.0 Creatinine (mmol/L) <110 38 \200\22390 p CO 2 (kPa) 4.5 \200\2236.0 (34 \200\22346mmHg) 3.6 \200\2234.2 (27 \200\22332mmHg) p O 2 (kPa) > 10.6 ( > 80.6mmHg) > 10.6 ( > 80.6mmHg) HCO 3 \200\223 (mmol/L) 24 \200\22328 18 \200\22323 \200\230All pregnant women attending (accident and) emergency departments with anything ot her than minor complaints should be seen quickly and in conjunction with an obstetrician or senior midwife. \200\231 (See http://www.cmace.org.uk/ ). 578 CHAPTER 13 Obstetrics and gynecology Emergency normal delivery Sometimes even the best laid plans for controlled delivery in the labor ward go awry and patients present in an advanced stage of labor and deliver in the E D. This is particularly likely in a very rapid ( \200\230precipitate \200\231) labor. ED st aff therefore need to know about normal delivery. Labor At onset of labor, painless and irregular (Braxton Hicks) contractions are replaced b y painful uterine contractions with cervical dilatation ( > 3cm) \200\230show \200\231 (mucus/blood discharge). There may be rupture of membranes. Presentation In the ED only \200\230OA \200\231 (occiput anterior) vertex presentations ar e likely to proceed so fast that delivery occurs before specialist help arrives. Stages of labor First Onset of labor until cervix is fully dilated (10cm). Usually lasts > 6hr. The upper part or \200\230segment \200\231 of the uterus contracts, the lower segment (including the cervix) dilates. Contractions i in frequency (every 2min) and duration (las t 1min). The head starts to descend. Second Full dilatation until baby is born. Lasts 8 40m in in primigravida, 8 20min in multigravida. Contraction of upper segment, abdominal muscle s and diaphragm cause head to descend then rotate (usually to lie occiput anterior). An ove rwhelming desire to push helps expel the baby. Third Placenta and membranes deliver and ute rus retracts ( 8 15min). Assessment of a patient in labor Check pulse, BP, and palpate the abdomen. Listen for fetal heart sounds with fetal stethoscope or Doppler probe (rate should be 120 \200\223160/min). Gently examine the perineum. Do not fully examine the vagina unless the head is crowning a nd birth is imminent. Instead, transfer to labor ward. Management of delivery (see Fig. 13.2) \200 Call obstetric/pediatric/anesthetic help and encourage partner to stay. \200 Offer Entonox (50:50 mixture of nitrous oxide and O 2 ). \200 Don sterile gloves and stand on the patient \200\231s right. \200 As head crown s discourage bearing down: advise rapid shallow breaths. \200 Use left hand to control es cape of head (to prevent perineal tearing). \200 Press gently forwards with right thumb a nd \201 ngers either side of anus. \200 Once head is delivered, allow it to extend. \200 Feel for cord around neck: slip it over head, or if impossible, clamp, and divide. Allow anterior shoulder to deliver \201 rst (mother pushing if necessary). \200 Give 5U oxytocin and 500mcg ergometrine IM (Syntometrine ). \200 Deliver the baby, wrap him/h er up and resuscitate as necessary ( b p.642). Management of the cord Once baby cries and cord pulsation ceases, hold baby level with moth er and clamp the cord twice (15cm from umbilicus). Divide between clamps. Place a plastic H ollister crushing clamp 1 \200\2232cm from umbilicus and cut 1cm distally. Check that 2 nor mal arteries are present in the cord. 579 EMERGENCY NORMAL DELIVERY Management of the third stage A few minutes after delivery, regular contractions begin agai n, causing the placenta to detach. The cord may be seen to move down accompanied by a small gush of blood. The placenta may be felt in the vagina. The Brandt \200\223 Andrews techniq ue helps removal: apply gentle downwards traction on the cord whilst exerting upward pressu re on uterus (preventing inversion). Examine placenta carefully. Give Rhesus anti-D immunog lobulin if Rh \200\223ve ( b p.582). Immediate post-partum problems are the domain of the specialist and include: post-partum hemorrhage, amniotic \202 uid embolism, uterine ruptu re, or inversion. (1) 1st stage of labor. The cervix dilates. After full dilatation the head flexes further a nd descends further into the pelvis. (4) Birth of the anterior shoulder. The shoulders rotate to lie in the anteroposterior diam eter of the pelvic outlet. The head rotates externally. Downward and backward traction of t he head by the birth attendant aids delivery of the anterior shoulder. (2) During the early second stage the head rotates at the level of the ischial spine so the occiput lies in the anterior part of pelvis. In late second stage the head broaches the vu lval ring (crowning) and the perineum stretches over the head. (5) Birth of the posterior shoulder is aided by lifting the head upwards whilst maintaining traction. (3) The head is born. The shoulders still lie transversely in the midpelvis. Fig. 13.2 Management of pregnancy. 580 CHAPTER 13 Obstetrics and gynecology Dif \201 culties in normal delivery Meconium-stained liquor See b Cardiopulmonary resuscit ation of the newborn, p.644. Imminent perineal tear The risk of perineal tearing may be minimized by controlled delivery . An extensive tear risks the integrity of the external anal sphincter. If a tear is immine nt, perform an episiotomy (Fig. 13.3 ). In \201 ltrate 5 \200\22310mL of 1 % lidocaine pos tero-laterally from the posterior fourchette. Cut the perineal tissues postero-laterally us ing straight scissors with blunt points (see diagram below), avoiding large veins. After de livery, carefully examine the episiotomy wound which needs to be closed in layers using abs orbable sutures. Line of incision Anal sphincter Fig. 13.3 Performing an episiotomy. Dif \201 culty in delivering the shoulders (shoulder dystocia) After delivery of the head, the shoulders usually rotate to lie in an antero- posterior (AP) direction, so the \201 rst one can be delivered anteriorly. If this does not occur, apply gentle digital pressure to obtain rotation. Try to help delivery of the anterior shoulder by gently bending the bab y \200\231s neck towards the mother \200\231s anus. The reverse action may then deliver the posterior shoulder. If these maneuvers are unsuccessful, hook a \201 nger into the axill a of the anterior shoulder to bring it down. This page intentionally left blank 582 CHAPTER 13 Obstetrics and gynecology Vaginal bleeding in pregnancy Vaginal bleeding in pregnancy produces understandable materna l distress. It may indicate serious illness that is a threat to the life of both the fetus and mother. Causes An indication of possible causes of vaginal bleeding related to pregnancy is apparen t from gestation (see opposite). Bleeding may, of course, be unrelated to pregnancy. Pregnancy testing Even if the patient denies pregnancy and there is no history of amenorrho ea, consider pregnancy. Most pregnancy tests look for B -HCG produced by the developing tro phoblast. Serum B -HCG levels rapidly i so that pregnancy may be con \201 rmed by serum te sts within days of implantation and remain + ve until 20 weeks. Urine tests have improved c onsiderably in recent years, but do not rely upon them to de \201 nitely exclude pregnancy . USS easily demonstrates most pregnancies by 5 weeks after LMP. Principles of treating blood loss in pregnancy \200 Give O 2 . \200 Obtain venous acces s with large bore cannulae and replace \202 uids aggressively. Consider coagulopathy: obtain FBC and clotting screen. \200 Consider prophylaxis against Rhesus haemolytic disease of the newborn. Anti-D immunoglobulin A Rhesus \200\223ve mother exposed to Rh + ve fetal blood during pre gnancy may develop antibodies. These IgG antibodies may cross the placenta during subsequen t pregnancies and cause Rhesus haemolytic disease of the (Rh + ve) newborn. The production of maternal antibodies may be prevented by appropriate use of anti-D Ig. Consider this ever y time that there is possible foeto-maternal bleeding (ruptured ectopic pregnancy, spontane ous abortion, trauma, antepartum hemorrhage, labor, and delivery). Guidelines have been pro duced for the use of anti-D Ig (see www.rcog.org.uk ). Check the Rhesus and antibody status of all women with bleeding in early pregnancy and give 250U anti-D Ig IM to those that are Rh \200\223ve and non-immune. After delivery or bleeding occurring in later pregnancy, Rh \200\223ve mothers are likely to require larger doses of anti-D Ig (see BNF ). Therefore, check the Rhesus and antibody status and also perform a Kleihauer test. This will give an indication of the extent of any foeto-maternal hemorrhage: Blood Transfusion Service will a dvise. 583 VAGINAL BLEEDING IN PREGNANCY Causes of vaginal bleeding in pregnancy Table 13.2 Causes of vaginal bleeding in pregnancy Pregnancy related Non-pregnancy related 1st trimester Spontaneous abortion At any stage Infection Ectopic pregnancy Vaginal ulcers Trophoblastic disease Vaginal in \202 ammation Cervical erosions Cervical polyps Coagulation disorders Trauma 2nd trimester Spontaneous abortion Trophoblastic disease Abruptio placentae Placenta praevia 3rd trimester Abruptio placentae Placenta praevia \200\230Show \200\231 of pregnancy Vasa praevia 584 CHAPTER 13 Obstetrics and gynecology Spontaneous abortion Terminology Use the term \200\230miscarriage \200\231 (not \200\230a bortion \200\231) with patients. Both refer to fetal loss before 24 weeks. Spontaneous abor tion affects > 20 % pregnancies. Threatened abortion refers to vaginal bleeding through a c losed cervical os. 50 % proceed to miscarry. If the cervix dilates or products of conceptio n are passed, abortion is inevitable. Inevitable abortion becomes complete abortion if all products are passed. Retained products of conception in an incomplete abortion may become i nfected, causing a septic abortion . Alternatively, products may be retained as a missed ab ortion , which carries a risk of disseminated intravascular coagulation (DIC). Etiology Mothers may feel guilty, but the causes are largely beyond their control. Risk fac tors include: \200 Chromosomal anomalies ( > 50 % ). \200 First pregnancy, maternal dis ease, and age > 30 years. \200 Uterine abnormalities. \200 Drugs (especially isotretino in). \200 Cervical incompetence, immunological factors, and trauma. Approach Establish the gestation. Think: is this a ruptured ectopic pregnancy? Vaginal blee ding in spontaneous abortion ranges from light to severe. Severe bleeding with hypovolaemia may occur in inevitable abortion. Abdominal pain is associated with a lower chance of feta l survival. Any pain with threatened abortion tends to be light and crampy. Severe pain and bleeding with hypotension and bradycardia implies \200\230cervical shock \200\231, where products of conception are stuck in the cervical os. Abdominal or cervical tenderness sugge sts an alternative diagnosis (ectopic pregnancy or septic abortion). Vaginal examination pr ovides other important clues: look for cervical dilatation (remember that the external os o f a multigravida usually accepts a \201 ngertip) and products in the os. Investigation USS may exclude ectopic pregnancy and indicate fetal viability: local policy will determine who performs this. Urine pregnancy tests remain + ve for several days after fetal death. Check Rhesus status and baseline serum B-HCG. Cross-match and obtain FBC if sh ocked. Treatment Resuscitate if signi \201 cant pain or hemorrhage and refer urgently. If cervica l shock is present, remove products of conception from the cervical os using sponge forceps . If severe bleeding continues, give 500mcg ergometrine IM. Unfortunately, no intervention appears to alter fetal survival in threatened abortion. Patients with light bleeding, no ab dominal pain, and a closed os (threatened abortion) may be allowed home after USS and gynec ology review. Reassure, emphasize that it is not her fault, advise bed rest and abstinence from sexual intercourse until gynecology follow-up in 2 days. Provide Rhesus anti-D Ig 250u IM if Rh \200\223ve and non-immune. 585 SPONTANEOUS ABORTION Septic abortion Sepsis may follow spontaneous, surgically induced or \200\230backstreet \200\231 abortion. Organisms S. aureus, C. welchii, Bacteroides, E. coli, streptococci, Clostridium sordelli . Features vaginal bleeding, offensive discharge, i T , d BP, uterine tenderness, periton itis. Note that pyrexia is not invariable \200\224 particularly with Clostridium sordelli which can result in a severe infection with high mortality. Obtain FBC, clotting screen, blood cultures, blood lactate, vaginal swabs, X-match, Rhesus status, erect CXR (to look for free gas). Resuscitate with IV \202 uids, give co-amoxiclav 1.2g IV, follow the severe sepsis guidel ines ( b p.59) and refer urgently. Monitor urine output and consider central and arterial l ines. Missed abortion Very occasionally presents several weeks or months after fetal death with n o expected features of pregnancy, a \200\223ve pregnancy test and DIC. Resuscitate, and in volve senior obstetrician and hematologist. 586 CHAPTER 13 Obstetrics and gynecology Ectopic pregnancy Gestational sac implantation outside the uterus has i and now occurs in 8 1 in 100 pregnancies in the UK. 96 % implant in the Fallopian tube, 2 % in the interstitia l part of uterus, 1.5 % intra-abdominally. The risk of heterotopic pregnancy (combined intr auterine and ectopic pregnancy) is 8 1 in 4000. Importance Ectopic pregnancy is the commonest cause of maternal mortality in the \201 rst trimester. The diagnosis is frequently missed. Consider it in any young woman presenting w ith abdominal pain or vaginal bleeding, especially when combined with an episode of syncope . Risk factors These include anything which delays or limits normal transit of the ferti- liz ed ovum to the uterus: PID, pelvic surgery/adhesions, previous ectopic, endometriosis, assi sted fertilization, IUCD, progesterone only pill, con- genital anatomical variants, ovarian and uterine cysts/tumors. Note that although pregnancy is unusual after tubal ligation, wh en it does occur there is a relatively high chance ( 8 1 in 6) of it being an ectopic pregn ancy. Pathology Implantation of the gestational sac in the Fallopian tube may have three results: \200 Extrusion (tubal abortion) into the peritoneal cavity. \200 Spontaneous involutio n of pregnancy. \200 Rupture through the tube causing pain and bleeding. Implantation in a uterine horn is particularly dangerous: pregnancy may reach 10 \200\22314 weeks before ru pture. Exceptionally, intraperitoneal pregnancies may proceed almost to term. Symptoms Ectopic pregnancy may present with sudden severe lower abdominal pain with collaps e or fainting, and vaginal bleeding. There is usually (but not always) a history of amenorr hoea (often 8 weeks). Hemorrhage may cause shoulder tip pain (from blood irritating the dia phragm) and features of hypovolaemia. Nausea and vomiting are common. Many patients have more chronic symptoms, with recurrent abdominal pain and slight irregula r vaginal bleeding, which may be fresh or dark (like \200\230prune juice \200\231). Pain m ay have continued for > 1week before presentation, occasionally as long as 4 weeks. The pai n may be worse on defecation. Some patients have no vaginal bleeding. Enquire about symptoms of pregnancy (eg breast tenderness) and possible risk factors for ec topic pregnancy. 587 ECTOPIC PREGNANCY Signs Look for hypovolaemic shock. If present, volume replacement must accompany full asses sment. Abdominal tenderness is variable, ranging from mild to severe with peritonism. Culle n \200\231s sign (discolouration around the umbilicus) is of historical interest only. Bima nual vaginal examination reveals tender adnexa and sometimes a mass, but may be better defe rred to a specialist (risk of i bleeding). Speculum inspection usually shows vaginal blood. Investigation Must not delay resuscitation and referral. Pregnancy test is almost always + ve, but serum B-HCG levels are lower than expected for normal pregnancy. Transabdominal USS is useful if it demonstrates an intrauterine pregnancy, free \202 uid in the pouch of Douglas and/or an adnexal mass. Frequently it is inconclusive. Transvaginal USS may be better. Differential diagnosis \200 Threatened abortion : bleeding is usually more severe ( b p.5 84). \200 Ruptured corpus luteum cyst : the corpus luteum supports pregnancy for the \201 rst 6 \200\2238 weeks. Rupture causes sudden peritoneal irritation, but rarely bleeds signi \201 cantly. PID ( b p.573): Note that ectopic pregnancy can cause mild pyrexia and a raised WCC, which may easily be misinterpreted as evidence of pelvic infection. Trophoblastic disease ( b Vaginal bleeding in later pregnancy, p.588). Treatment Give O 2 , insert two large (12 or 14G) cannulae, cross-match 6U of blood, reques t Rhesus status. Resuscitate initially with crystalloid IV \202 uids as necessary. If sus pected, refer urgently to the gynecology team since sudden deterioration may occur. Signi \201 cant hemorrhage requires urgent surgery. Alert the anesthetist and theater team early. Check Rhesus and antibody status: anti-D immunoglobulin may be needed ( b p.582). 588 CHAPTER 13 Obstetrics and gynecology Vaginal bleeding in later pregnancy Gestational trophoblastic disease Occasionally, a ferti lized ovum may form abnormal trophoblastic tissue, but no fetus. The pathological spectrum ranges from benign hydatidiform mole to invasive choriocarcinoma. Choriocarcinoma is relati vely rare, affecting 8 1 in 40,000 pregnancies. Presentation Usually vaginal bleeding at 12 \200\22316 weeks, with passage of tissue, which may resemble frogspawn. Often accompanying abdominal pain and sometimes pre-eclampsia or eclampsia. The uterus may be much larger tha n expected for dates. DIC may occur. Investigations USS shows \200\230snowstorm \200\231 and no fetus. Serum HCG is grossly i . Management Obtain venous access, serum HCG, FBC, group and save, IV \202 uids/resuscitati on, and refer. Antepartum hemorrhage Bleeding after 20 weeks occurs in 2.5 % of pregnancies. Abruptio plac entae and placenta praevia are most likely causes, although other cervical or vaginal lesio ns may be responsible. Abruptio placentae Premature separation of the normally situated placenta affects 8 1 % of pregnancies. It causes hemorrhage which may risk the fetus, depending on the extent of plac ental involvement, and rapidity of separation. Risk factors Pre-eclampsia, previous abrupti on, trauma ( b p.594), smoking, i parity, cocaine. Presentation There is usually some vagin al bleeding ( \200\230revealed hemorrhage \200\231), but occasionally bleeding is limited t o the con \201 nes of the uterus ( \200\230concealed hemorrhage \200\231). In either case, there may be much more utero-placental bleeding than is immediately apparent. There may be abdominal pain and tenderness or back pain. Abruptio placentae may precipitate labor. A la rge bleed can cause DIC or absent fetal heart sounds. Placenta praevia The placenta is situated wholly or partly over the lower uterine segment a nd cervical os. Risk factors Mother aged > 35 years, high parity, previous placenta praevia, twins, uterine abnormalities (including previous Caesarian section). Presentation Most present with bright red painless vaginal bleeding in the third trimester. 15 % present in labor. If placenta praevia is a possibility, do not perform digital or speculum vaginal examinatio n. Vasa praevia Rarely, an abnormal fetal blood vessel may be attached to the membranes over t he internal os. Hemorrhage may cause fetal exsanguination, usually during labor. 589 VAGINAL BLEEDING IN LATER PREGNANCY Management of antepartum hemorrhage \200 Call an obstetrician immediately. \200 Give O 2 . \200 Obtain venous access (2 large bore cannulae) and resuscitate with IV \202 uids as necessary. Send U&E, FBC, blood glucose, cross-match, Rhesus and antibody status, Kleihauer test, clotting screen. \200 Monitor the fetus (cardiotocography). \200 USS locates the placenta, demonstrates the fetus and may show concealed hemorrhage. Give anti-D immunoglobulin as advised by Blood Transfusion Service if Rh \200\223ve ( b p.582). 590 CHAPTER 13 Obstetrics and gynecology Abdominal pain in pregnancy Approach Attempting to deduce the cause of abdominal pain can o rdinarily be quite dif \201 cult: in pregnancy it is even more so. Some possible underlyin g diseases may be causing unseen fetal distress and can produce rapid maternal deterioratio n. Therefore, triage ahead, contact the obstetrician, and resuscitate vigorously. Initial i nvestigations usually include BMG, uri- nalysis, blood tests, and USS. Vaginal bleeding acc ompanying abdominal pain implies a gynecological or obstetric problem. Remember, however, t hat the reverse is not necessarily true: ruptured ectopic pregnancy and concealed hemorrhag e in abruptio placentae may present without vaginal bleeding. In later pregnancy, even if t here is doubt as to whether the principal problem is obstetric or not, involve the obstetri cian at an early stage. Pregnancy related causes of abdominal pain The following are considered elsewhere: \200 E ctopic pregnancy ( b p.586). \200 \200\230Red degeneration \200\231 of a \201 broid ( b Uterine problems, p.572). \200 Gestational trophoblastic disease ( b Vaginal bleeding i n later preg- nancy, p.588). Abruptio placentae ( b p.588). \200 Onset of labor ( b Emergency normal delivery, p.578). Torsion, rupture, or hemorrhage into an ovarian cyst This may involve the corpus luteum of pregnancy. Sudden onset lower abdominal pain results. USS may demonstrate the problem. Acute polyhydramnios Excessive amniotic \202 uid may complicate pregnancy involving uni-o vular twins. Pain and vomiting is accompanied by a large abdomen for gestation and an unusu ally mobile fetus. Pre-eclampsia Abdominal pain (particularly right upper quadrant pain) in pregnancy may re \202 ect pre-eclampsia (see b p.592). Check BP and urinalysis and refer urgently. 591 ABDOMINAL PAIN IN PREGNANCY