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Ovid: Oxford Handbook of Accident and Emergency Medicine

Editors: Wyatt, Jonathan P.; Illingworth, Robin N.; Clancy, Michael J.; Munro, Philip T.; Robertson, Colin E. Title: Oxford Handbook of Accident and Emergency Medicine, 2nd Edition Copyright ©2005 Oxford University Press > Table of Contents > Chapter 13 – Obstetrics and gynaecology Chapter 13 Obstetrics and gynaecology P.538
Gynaecological problems Gynaecological history and examination in A&E require particular attention to privacy and confidentiality. Always obtain a full menstrual, contraceptive and sexual history: it is usually sensible to interview a patient without other family members being present. Wearing gloves, examine patients in an unhurried manner, in the presence of a chaperone, who might usefully ‘guard’ the door to prevent sudden inadvertent interruption. Use a chaperone even when the patient is being examined by female members of staff. Document the name of the chaperone in the medical record. Full examination includes digital and speculum vaginal examination, although this is not appropriate in A&E in certain circumstances (children, patients with painful vulval ulcers). Vulvovaginal pain Distinguish between dysuria, dyspareunia (pain on vaginal penetration) and constant vulvovaginal pain/irritation. The latter is often associated with infection or ulceration. Enquire about other symptoms (abdominal pain, vaginal discharge and bleeding). Vulval ulcers

  • Herpes simplex virus is sexually transmitted and usually due to type II, but is increasingly due to type I virus (responsible for cold sores). Primary infection is extremely painful, lasting up to 3wks and sometimes causing urinary retention. Look for shallow yellow vulvovaginal or perineal ulcers with red edges. Cervical ulcers may also be present, although pain may prevent speculum examination. Refer primary infections immediately for aciclovir, analgesia and to exclude co-existent infection. Secondary infections are less severe, but may last up to a week. Treat with topical and oral aciclovir (200mg five times a day for 1wk) and arrange GU follow-up, with advice to avoid sexual contact meantime. Do not prescribe aciclovir in pregnancy, but arrange for an obstetric opinion.
  • Other STDs may cause ulceration: syphilis (non-tender indurated ulcers (‘chancres’) and lymphadenopathy), chancroid, lymphogranuloma venereum and granuloma inguinale (p228). Refer to GU clinic and advise to abstain from sexual contact until treated.
  • Squamous carcinoma causes indurated ulcers with everted edgesespecially in the elderly. Refer.
  • Consider also: Behçet’s syndrome (arthritis, iritis, genital/oral ulceration), TB, Crohn’s disease.

Painful lumps

  • Bartholin’s abscess—infection of vestibular (Bartholin’s) cyst/gland at the posterior part of the labium majus is usually due to Staph., Strep. or E. coli, but may be due to N. gonorrhoea. Refer for incision and drainage (under GA) and a full GU screen.
  • Infected sebaceous cysts may also require incision and drainage under GA.
  • Urethral carbuncle – this small, red, painful swelling at the external urethral meatus is due to urethral mucosal prolapse. It may cause dysuria. Refer to an appropriate clinic to consider excision or diathermy.

P.539
Pruritis vulvae Vulval irritation may be caused by a generalized pruritic skin disorder (eg eczema), infection (particularly candidiasis) and other causes of vaginal discharge (p540), urinary incontinence, threadworms and vulval warts. Genital warts (including condylomata accuminata) are usually sexually transmitted and caused by human papillomavirus 6. Other STD may coexist. Refer to GU clinic. Vulvovaginal problems in children The hymen usually acts as an effective barrier to infection in children. Vaginal infection is therefore relatively uncommon. Pain, irritation and vaginal discharge may result from threadworms or FB, but may be due to sexual abuse. Vaginal examination in young children is not appropriately performed in A&E: it may require GA and should be undertaken by an expert. Adopt a low threshold for referring such patients. P.540
Vaginal discharge May be physiological, or due to atrophic vaginitis, infections including STDs, cervical and endometrial carcinoma, a variety of fistulae and FBs. Physiological A creamy/white discharge is normal. Variation in its consistency and amount occurs with puberty, pregnancy, OCP use, ovulation and immediately prior to menstruation. Atrophic vaginitis A profuse, sometimes bloody, yellow discharge may result from vaginal epithelial thinning due to ↓oestrogen levels associated with the menopause. This responds well to local topical or oral oestrogens, most appropriately prescribed by the patient’s GP. ‘Thrush’ Candida albicans is the commonest vaginal infection. A white discharge accompanies a red painful vulvovaginitis. Occurs in pregnancy, after oral antibiotics and with HIV and diabetes: check for glycosuria. Treatment options include clotrimazole pessaries, oral fluconazole and topical application of live yoghurt. Advise GP for follow-up for any continuing symptoms. Other infections Refer patients suspected of the following STDs to GU clinic and advise abstinence from sexual contact in the meantime:

  • Neisseria gonorrhoea may be asymptomatic, cause urethritis (dysuria), cervicitis (vaginal discharge), or PID (p546).
  • Trichomonas vaginalis infection results in a smelly profuse yellowdischarge.
  • Chlamydia trachomatis causes chronic cervicitis, Reiter’s syndrome and sometimes PID. It may be present asymptomatically.
  • Gardnerella vaginalis produces a brown offensive discharge.

Cervical and endometrial carcinoma Classically presenting with bleeding between periods, these may causedischarge. Refer to a gynaecologist. Fistulae Colovaginal fistulae may follow diverticulitis or locally invasive colorectal carcinoma. Other fistulae (including vesicovaginal and ureterovaginal) may occur after pelvic surgery. Refer for admission and investigation. Foreign bodies Tampons, condoms and various other items may be ‘lost’ or forgotten about in the vagina. Removal with forceps under direct vision should cure the offensive vaginal discharge. If a condom has been removed, ascertain whether post-coital contraception is required (p542). Consider hepatitis B/HIV prophylaxis and GU referral for STD screen, depending upon the circumstances. Vaginal tampons (particularly highly-absorbent ones which have been left in situ for many hours) are associated with ‘toxic shock syndrome’ (see below). P.541
Toxic shock syndrome Tampons used during menstruation have been implicated in many cases of the ‘toxic shock syndrome’. First described in 1978, it is caused byexotoxin produced by Staph. aureus (usually TSS toxin 1), or occasionally, Strep. Multi-organ failure may follow. Features High fever, headache, vomiting, diarrhoea, myalgia, alteredconscious level, hypotension and a widespread erythematous macular rash (with subsequent desquamation 1 week later, especially of palms and soles). Diagnosis Based upon clinical findings. Recent menstruation and the above features should prompt suspicion. Investigation Includes vaginal examination. U&E, LFTs, clotting screen, FBC, ABG, blood and vaginal cultures, ECG, CXR. Treatment If due to a tampon: remove it! Obtain venous access and give crystalloid for hypotension. If refractory, consider measuring CVP, starting inotropic support and refer to ITU. Give an anti-staphylococcal antibiotic to prevent recurrence. The use of antitoxin antibodies remains uncertain. P.542
Contraceptive problems Missed pill—refer to BNF The risk of pregnancy is greatest if OCP is missed in first 7 days of cycle. If one OCP in first 7 days is missed, or 2 or more are missed midcycle, consider post-coital contraception. If >12h late taking one OCP during midcycle, or diarrhoea is experienced midcycle, advise to continue taking OCP and use additional barrier precautions (condoms). Advise early GP follow-up for further advice. Post-coital contraception Women may attend A&E requesting post-coital contraception after:

  • isolated unprotected sexual intercourse
  • burst or lost condom
  • missed OCP
  • complete or partial expulsion of IUCD
  • rape

The risk of pregnancy following unprotected intercourse is greatest during 5days around ovulation, but exists at other times also. Patients given post-coital contraception require assessment, treatment including counselling and follow-up: usually this will be with the GP and/or family planning clinic. Options include levonorgestrel and insertion of IUCD. Levonorgestrel must be given within 72h of intercourse (not just ‘the morning after’—use of this term is thus discouraged), IUCD must be inserted within 5 days of intercourse. Both act principally to render the endometrium hostile to implantation and can therefore be properly described as contraceptives, not abortifacients. This is an important distinction, both legally and for the patient. Levonorgestrel (previously called ‘the morning after pill’ This can now be directly sold to women aged over 16yrs by pharmacists in the UK. It is usually the preferred option if patient presents within 72h of unprotected intercourse. Exclude contraindications (acute porphyria, pregnancy, focal migraine), then give levonorgestrel 1.5mg (Levonelle-2) as soon as possible. Advise the patient to return if she vomits shortly after taking the medication: give a replacement dose if vomiting occurs within 3hrs of taking it. Explain that, properly taken, this has a failure rate of only 1–2%. Arrange follow-up (usually with the GP) in 3wks to confirmthat menstruation has occurred. Advise alternative contraception(eg condoms) meantime and discuss future contraception plans. Advise also about theoretical risk of ectopic pregnancy: instruct her to return if she develops abdominal pain. Document that this advice and counselling was given to the patient. Note: hormonal emergency contraception is less effective if the patient is already taking enzyme-inducing drugs: take specialist advice. Options include an IUCD (below) or ↑ dose of levonorgestrel to 2.25mg (see BNF). IUCD This may be useful for patients unable to take the OCP (eg previouspulmonary embolus), patients who wish to use IUCD long-term and for those presenting between 3 and 5 days after unprotected intercourse. Failure is very rare. Insertion is uncomfortable and requires appropriate training: refer to the gynaecology team. Note that IUCD should not be used with a history of recent PID. P.543
Prescribing to patients on OCP Both progestogen only oral contraceptives and (combined) OCP may fail if enzyme inducing drugs are prescribed. These include: rifampicin, rifabutin, carbamazepine, phenytoin, topiramate, griseofulvin, primidone and phenobarbitone. Patients need alternative or additional contraception if these drugs are started. Rifampicin and rifabutin are such potent enzyme-inducing drugs that contraceptive precautions should continue for at least 4wks, even after a short course of rifabutin or rifampicin (as used for prophylaxis of meningococcal infection (p215). Antibiotics and the OCP (refer to BNF) Broad spectrum antibiotics commonly prescribed in A&E may interfere with oestrogen absorption and cause contraceptive failure. Before prescribing antibiotics to a female of childbearing age, ask whether she is taking the OCP. Advise additional contraceptive precautions (eg condoms) whilst taking the antibiotics and for 7days after. If these 7days run beyond the end of a packet, start the next packet immediately without a break. Document in the notes that this advice has been given. P.544
Genital injury and assault The history may be misleading. Combine a high index of suspicion with a full examination to exclude significant 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 theatre. 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 to peritonitis. Obtain venous access, erect CXR (for free gas), abdominal X-Ray (for FB), group and save and refer. Refer other vaginal tears without peritonitis for exploration and repair. Rape and sexual assault Rape is defined in the UK as vulval penetration by the penis without consent. Rape and other forms of sexual assault are believed to be grossly under-reported. Those who do report it have special requirements. Privacy is essential: ideally, a specially equipped room will be devoted to assessment of women who have been sexually assaulted. Ensure that a female member of staff is present throughout. Documentation must be legible and meticulous. An established protocol will allow prompt and thorough investigation and treatment. Usually, A&E staff provide emergency treatment and resuscitation, but most of the other aspects, including collection of forensic evidence are dealt with by a police surgeon, together with a gynaecologist. Sometimes, women initially decline police involvement: full assessment and documentation may prove useful if there is a change of mind. Whatever the extent of involvement of A&E staff, address the following: First exclude life-threatening or serious injuries. History Establish the type, date, time and place of the assault. Obtain a contraceptive/ sexual history and enquire about LMP/pregnancy. Examination Look for evidence of vaginal, oral or anal injury (and take swabs). Record any other injuries, such as bites, bruising or skin wounds (photographs useful). Investigation Obtain written informed consent. Retain clothing, loose hairs, fingernail clippings and tampons for evidence. Take appropriate swabs (vaginal, oral, anal). Perform a pregnancy test. Take and store blood for future DNA testing. Treatment

  • Resuscitate as necessary. Refer urgently the 1% of patients who have significant genital injuries (eg vaginal tears) requiring surgical intervention.
  • Consider the need for post-coital contraception (see p542).
  • Consider prophylaxis against hepatitis B, HIV and tetanus (p404).
  • Arrange follow-up to exclude STD. Consider antibiotic prophylaxis against STD if the patient is unlikely to attend follow-up: liaise with the GU team.
  • Provide initial counselling and ensure a safe place to stay (social worker may arrange this).
  • Arrange future counselling. Inform of independent local advice (eg Rape Crisis Centre).

Telephone advice Women may telephone A&E for advice after being raped. Advise them to inform the police immediately and then attend A&E. Discourage from wash-ing, changing clothes, using a toilet or brushing teeth before being examined. P.545
P.546
Gynaecological pain Gynaecological disorders presenting to A&E with abdominal pain may be difficult to distinguish from other disorders (p482). Take a full history of the pain: sudden onset of severe colicky pain follows ovarian torsion and acute vascular events; more insidious onset and continuous pain occur in infection and inflammation. Radiation into the back or legs suggests gynaecological origin. Other clues in the history include co-existing symptoms of vaginal discharge, vaginal bleeding or missed LMP. Abdominal and pelvic pain in early pregnancy may be due to ectopic pregnancy or threatened abortion (p558): both occur in patients who do not realize that they are pregnant or who deny the possibility of pregnancy due to embarrassment. Pain related to the menstrual cycle Consider first: could any associated vaginal bleeding be from ectopic pregnancy or threatened abortion? Physiological dysmenorrhoea Pain regularly preceding menstruation and peaking on the first 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 ≈30yrs with dysmenorrhoea and menstrual problems, infertility and dyspareunia. Symptoms are usually chronic and recurrent in a cyclical fashion and are appropriately followed up by the GP. Occasionally, an endometrial 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 pre-menstrually and may also cause significant haemorrhage, requiring resuscitation. Mittelschmerz Mid-cycle extrusion of an ovum from a follicular cyst can cause abdominal pain, which seldom requires admission or investigation. Pelvic inflammatory disease This term includes infection which has spread from the cervix to the uterus (endometritis), Fallopian tubes (salpingitis), ovaries (oophoritis) or adjacent peritoneum (peritonitis). Severity ranges from chronic low grade infection (with relatively mild symptoms) to acute infection (with severe symptoms) which may result in abscess formation. Causes 90% are sexually transmitted: sexually active women aged 15–20yrs are at particular risk. Most of the remaining 10% follow pregnancy terminations or dilatation and curettage. Organisms Chlamydia trachomatis commonest. Also: Neisseria gonorrhoea, Mycoplasma hominis, Ureaplasma urealyticum. Features Lower abdominal pain, vaginal discharge, nausea/vomiting, classically associated with fever, lower abdominal tenderness (±peritonism) and tender cervix and adnexa PV (‘chandelier sign’). Management Resuscitate with IV fluids if shocked. Check urinalysis and send high vaginal swab and cervical swab, FBC, ESR. Refer all suspected cases to the gynaecologist: even though not all will require admission, they will require antibiotics (eg ofloxacin + metronidazole) and follow-up. Sequelae Ectopic pregnancy (5 × ↑risk), infertility. P.547
Ovarian problems Torsion causes sudden onset sharp unilateral pain and usually involves an already enlarged ovary (cyst, neoplasm). Abdominal and PV tenderness may be present. Clinical diagnosis is difficult: if suspected, refer for USS and/or laparoscopy. Bleeding into an ovarian cyst may present similarly and require investigation. Uterine problems Perforation is seen especially in the presence of IUCD. Leiomyomas (‘fibroids’) may undergo torsion (sudden severe colicky pain with tender uterus), or may infarct (‘red degeneration’) particularly during pregnancy. Refer such suspected problems for specialist investigation. P.548
Vaginal bleeding See p556 for vaginal bleeding in known pregnancy. Triage forward patients with severe bleeding or evidence of hypovolaemic shock. Resuscitate first (O2, X-match and obtain Rhesus status, start IV fluids) and ask questions later. Most patients with vaginal bleeding, however, do not require resuscitation. Take a careful menstrual history and ask about associated symptoms. Attempt to assess the amount of bleeding. Interpretation of a patient’s description is notoriously difficult, but useful pointers are the presence of clots and the rate of tampon use. Always consider the possibility of pregnancy: remember that 15% of ruptured ectopic pregnancies present before a period is missed (p560). Examine for evidence of hypovolaemia and abdominal masses/tenderness. Depending upon the circumstances, speculum and bimanual vaginal examinations may be required: local policy will determine who should perform this. Menorrhagia Dysfunctional uterine bleeding Heavy and/or irregular periods without obvious pelvic pathology may result from hormonal imbalance. 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 (fibroids) Often cause menorrhagia. May present with a painful complication, 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 Significant bleeding is a risk of any gynaecological operation. Resuscitate and refer. OCP problems Breakthrough bleeding on the OCP may be due to endometrial hyperplasia. Exclude treatable vaginal/cervical lesions, arrange a cervical smear and refer to GP. Cervical erosion Replacement of stratified squamous epithelium by columnar epithelium may produce a mucoid discharge with a small amount of post-coital or intermenstrual bleeding. The cervix appears red. Obtain a cervical smear and arrange follow-up. Cervical polyp Causes post-coital bleeding. Refer to the gynaecologist. 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 touch. Advanced disease may present with pyometra, ureteric obstruction, rectovaginal fistula. Arrange urgent gynaecology follow-up for any patient with an abnormal looking cervix. Uterine carcinoma Mostly adenocarcinoma. Classically presents with ↑heavy and frequent post-menopausal bleeding, but normal examination. Arrange assessment and diagnostic curettage with the gynaecologist. Other causes Thrombocytopenia, other coagulation disorders and anticoagulant drugs. P.549
P.550
The pregnant patient Pregnant patients presenting with emergency problems create understandable anxiety. Remember that there are two patients: one may be suffering unseen. Maintaining fetal oxygenation is crucial: call the obstetrician early. Terminology The 40wks of pregnancy are divided arbitrarily into three trimesters. Traditionally, problems in the first trimester are considered ‘gynaecological’— an important point for obtaining rapid referral. Gravidity = total number of pregnancies (eg a woman in first pregnancy is a ‘primigravida’) Parity = number of pregnancies after 24wks + number before (eg a woman who has had 1 child and 2 spontaneous abortions is described as 1 + 2; gravidity = 3) Abortion is fetal death before 24wks; stillbirth is fetal death after 24wks. Progression of pregnancy The fertilized ovum is carried by peristalsis and ciliary action to the uterine cavity, which it reaches as a blastocyst 5 or 6 days after ovulation. The blastocyst implants into the endometrium: the inner part forming the embryo, the outer part the membranes and placenta. Trophoblastic tissue produces human chorionic gonadotrophin (HCG), (peaking in first trimester) acting upon the corpus luteum, which is essential for pregnancy until the placenta can produce ostrogen and progesterone. HCG subsequently↓, whereas oestrogen and progesterone↑. Symptoms of pregnancy Amenorrhoea, breast tenderness and fullness, polyuria, tiredness, nausea (appear by ≈6wks). Vomiting is common (50%), but occasionally may be severe enough to cause dehydration and weight loss (‘hyperemesis gravidarum’). Refer for admission and IV rehydration. Signs of pregnancy Not obvious in early pregnancy: uterine enlargement (see below), breast changes. Pregnancy testing—see p556. Maternal physiological changes Cardiac output↑ by 30%, peripheral vascular resistance↓: BP (especially diastolic) ↓slightly. Blood vol↑ by 30%, plasma vol↑ by 45%, Hb↓ slightly. Systolic flow murmurs are common. Water retention occurs, causing ankle oedema and carpal tunnel syndrome. Ventilation↑: the patient may feel dyspnoeic. Backache is common. ↓lower oesophageal pressure causes heartburn; ↓gut motility causes constipation; ↑ venous pressure in pelvis may cause varicose veins and haemorrhoids. Platelets, ESR, cholesterol, fibrinogen↑; albumin↓. Diagnostic imaging in pregnancy Try to avoid X-rays and CT scans. Excessive radiation exposure could result in congenital malformation, growth retardation, neoplasia and death. However, do not withold necessary X-rays in life-threatening illness. In the case of head, neck and extremity X-rays, most views can be obtained without fetal risk by 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 appropriate imaging techniques with a radiologist. P.551
Prescribing in pregnancy and during breast-feeding Consult the BNF before prescribing drugs in pregnancy or during breast feeding. The following are generally considered safe in pregnancy: penicillin, cephalosporins, nystatin, paracetamol, chlorphenamine, cimetidine. Avoid the following: tetracyclines, streptomycin, warfarin, thiazide diuretics.

Figure. Uterine size in pregnancy

Normal values in pregnant and non-pregnant women

Value Non-pregnant Pregnant
Haematocrit 0.37–0.47 0.32–0.41
Haemoglobin (g/dL) 11.5–16.0 11.0–15.0
White cell count (/L) 4.0–11.0 × 109 5.0–16.0 × 109
Platelets (/L) 150–400 × 109 134–400 × 109
ESR (mm/h) (age in years + 10)/2 44–114
Fibrinogen (g/L) 2–4 4–6
Albumin (g/L) 35–50 28–40
Urea (mmol/L) 2.5–6.7 1.6–6.0
Creatinine (micromol/L) <150 38–90
pCO2 (kPa) 4.5–6.0 (34–46 mmHg) 3.6–4.2 (27–32 mmHg)
pO2 (kPa) >10.6 (>80.6 mmHg) >10.6 (>80.6 mmHg)
HCO3- (mmol/L) 24–30 18–23

P.552
Emergency normal delivery Sometimes even the best laid plans for controlled delivery in the labour ward go awry and patients present in advanced stage of labour and deliver in A&E. This is particularly likely in a very rapid (‘precipitate’) labour. A&E staff therefore need to know about normal delivery. Labour Onset of labour is heralded by the replacement of painless, irregular (Braxton Hicks) contractions with painful uterine contractions accompanied by cervical dilatation (>3cm) and possibly a ‘show’ (mucous discharge and blood). There may be rupture of the membranes. Presentation May be: vertex, face, brow, breech, shoulder. In A&E only ‘OA’ (occiput anterior) vertex presentations are likely to proceed so fast that delivery occurs before specialist help arrives. Stages of labour First Onset of labour until cervix is fully dilated (10cm). Usually lasts >6h. The upper part or ‘segment’ of the uterus contracts, the lower segment (including the cervix) dilates. Contractions↑ in frequency (every 2mins) and duration (last 1min). The head starts to descend. Second Full dilatation until baby is born. Lasts ≈40mins in primigravida, ≈20mins in multigravida. Contraction of upper segment, abdominal muscles and diaphragm cause head to descend then rotate (usually to lie occiput anterior). An overwhelming desire to push expels the baby. Third Birth until placenta and membranes are delivered and uterus retracted (≈15mins). Assessment of a patient in labour Check pulse and BP and feel abdomen. Listen for fetal heart sounds with Pinard or doppler probe (rate should be 120–160/min). Gently examine the perineum. Do not fully examine the vagina unless the head is crowning and birth is imminent. Instead, transfer to labour ward. Management of delivery (see below)

  • call the obstetrician and anaesthetist/paediatrician
  • encourage the patient’s partner to remain with her
  • offer Entonox (50:50 mixture of nitrous oxide and O2)
  • don sterile gloves and stand on the patient’s right
  • once head crowns discourage her from bearing down: encourage rapid shallow breaths
  • use left hand to control rate of escape of head (to prevent perineal tearing)
  • press gently forwards with right thumb and fingers either side of anus
  • once head is delivered, allow it to extend
  • feel for cord around neck: slip it over head, or if impossible, clamp and divide
  • allow anterior shoulder to deliver first (mother pushing if necessary)
  • give 5u oxytocin and 500micrograms ergometrine IM (Syntometrine®)
  • deliver the baby, wrap it up/resuscitate it as necessary (p614)

Management of the cord Once baby cries and cord pulsation ceases, hold baby level with mother and clamp the cord twice (15cm from umbilicus). Divide between clamps. Place a plastic Hollister crushing clamp 1–2cm from umbilicus and cut 1cm distally. Check that 2 normal arteries are present in the umbilical cord. P.553
Management of the third stage A few mins after delivery, regular contractions begin again, causing theplacenta 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-Andrews technique helps removal: apply gentle downwards traction on the cord whilst exerting upward pressure on uterus (preventing inversion). Examine placenta carefully. Give Rhesus anti-D immunoglobulin if Rhesus -ve (p556). Immediate post-partum problems are the domain of the specialist and include: post-partum haemorrhage, amniotic fluid embolism, uterine rupture or inversion.

(1) 1st stage of labour. The cervix dilates. After full dilatation the head flexes further and descends further into the pelvis.
(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 vuval ring (crowning) and the perineum stretches over the head.
(3) The head is born. The shoulders still lie transversely in the midpelvis.
(4) Birth of the anterior shoulder. The shoulders rotate to lie in the anteroposterior diameter of the pelvic outlet. The head rotates externally. Downward and backward traction of the head by the birth attendant aids delivery of the anterior shoulder.
(5) Birth of the posterior shoulder is aided by lifting the head upwards whilst maintaining traction.

P.554
Difficulties in normal delivery Meconium-stained liquor Once the head is delivered, clear the upper airway using a wide bore soft suction catheter. Further management is discussed on p614. 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 imminent, perform an episiotomy. Infiltrate 5-10mL of 1% lidocaine postero-laterally from the posterior fourchette. Cut the perineal tissues postero-laterally using straight scissors with blunt points (see diagram below), avoiding large veins. After delivery, carefully examine the episiotomy wound which needs to be closed in layers using absorbable sutures.

Figure. Performing an episiotomy

Difficulty in delivering the shoulders (shoulder dystocia) After delivery of the head, the shoulders usually rotate to lie in an anteroposterior direction, so the first 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 baby’s neck towards the mother’s anus. The reverse action may then deliver the posterior shoulder. If these manoeuvres are unsuccessful, hook a finger into the axilla of the anterior shoulder to bring it down. P.555
P.556
Vaginal bleeding in pregnancy Vaginal bleeding in pregnancy produces understandable maternal distress. It may indicate serious illness which 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 apparent from gestation (see below). Bleeding may, of course, be unrelated to pregnancy. Pregnancy testing Even if the patient denies pregnancy and there is no history of amenorrhoea, consider pregnancy. Most pregnancy tests look for ß-HCG produced by the developing trophoblast. Serum ß-HCG levels rapidly ↑ so that pregnancy may be confirmed by serum tests within days of implantation and remain +ve until 20wks. Urine tests have improved considerably in recent yrs, but do not rely upon them to definitely exclude pregnancy. USS easily demonstrates most pregnancies by 5wks after LMP. Principles of treating blood loss in pregnancy

  • Give O2.
  • Obtain venous access with large bore cannulae and replace fluids aggressively.
  • Consider coagulopathy: obtain FBC and clotting screen.
  • Consider prophylaxis against Rhesus haemolytic disease of the newborn.

Anti-D immunoglobulin A Rhesus -ve mother exposed to Rhesus +ve fetal blood during pregnancy may develop antibodies. These IgG antibodies may cross the placenta during subsequent pregnancies and cause rhesus haemolytic disease of the (Rhesus +ve) newborn. The production of maternal antibodies may be prevented by the appropriate use of anti-D Ig. Consider this every time there is possible feto-maternal bleeding (ruptured ectopic pregnancy, spontaneous abortion, trauma, antepartum haemorrhage, labour and delivery). Guidelines have been produced for the use of anti-D Ig (see http://www.transfusionguidelines.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 Rhesus -ve and non-immune. After delivery or bleeding occuring in later pregnancy, Rhesus -ve mothers may require larger doses of anti-D Ig. Therefore, check the Rhesus and antibody status and also perform a Kleihauer test. This will give an indication of the extent of any fetomaternal haemorrhage: Blood Transfusion Service will advise. P.557
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 inflammation
Cervical erosions
Cervical polyps
Coagulation disorders
Trauma
2nd trimester Spontaneous abortion
Trophoblastic disease
Abruptio placentae
Placenta praevia
3rd trimester Abruptio placentae
Placenta praevia
‘Show’ of pregnancy
Vasa praevia

P.558
Spontaneous abortion Terminology Use the term ‘miscarriage’ rather than ‘abortion’ with patients. Both refer to fetal loss before 24wks gestation. Spontaneous abortion occurs in at least 20% of pregnancies. Threatened abortion refers to vaginal bleeding through a closed cervical os. 50% proceed to miscarry. If the cervix dilates or products of conception 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 infected, causing a septic abortion. Alternatively, products may be retained as a missed abortion, which carries a risk of DIC. Aetiology Mothers may feel guilty, but the causes are largely beyond their control. Risk factors include:

  • chromosomal anomalies (>50%)
  • first pregnancy
  • maternal disease and age >30yrs
  • uterine abnormalities
  • drugs (especially isotretinoin)
  • cervical incompetence
  • immunological factors
  • trauma

Approach Establish the gestation. Strongly consider: is this a ruptured ectopic pregnancy? Vaginal bleeding 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 fetal survival. Any pain with threatened abortion tends to be light and crampy. Severe pain and bleeding combined with hypotension and bradycardia implies ‘cervical shock’, where products of conception remain stuck in the cervical os. Abdominal or cervical tenderness suggests an alternative diagnosis (ectopic pregnancy or septic abortion). Vaginal examination provides other important clues: look for cervical dilatation (remember that the external os of a multigravida usually accepts a fingertip) 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 ß-HCG. X-match and obtain FBC if shocked. Treatment Resuscitate patients with significant pain or haemorrhage and refer urgently to a gynaecologist. If cervical shock is present, remove products of conception from the cervical os using sponge forceps. If severe bleeding continues, give 500micrograms ergometrine IM. Unfortunately, no intervention has been proved to alter fetal survival in threatened abortion. Patients with light bleeding, no abdominal pain and a closed os (threatened abortion) may be allowed home after USS and gynaecology review. Reassure, emphasize that it is not her fault, advise bed rest and abstinence from sexual intercourse until gynaecology follow-up in 2 days. Provide Rhesus anti-D Ig 250u IM if Rhesus -ve and non-immune. P.559
Septic abortion Sepsis may follow spontaneous, surgically induced or ‘backstreet’ abortion. Organisms S. aureus, C. welchii, Bacteroides, E. Coli, streptococci. Features vaginal bleeding, offensive discharge, ↑T°, ↓BP, uterine tenderness, peritonitis. Obtain FBC, coagulation screen, blood cultures, vaginal swabs, X-match, Rhesus status, erect CXR (to look for free gas). Resuscitate with IV fluids, give co-amoxiclav 1.2g IV and refer urgently. Missed abortion Very occasionally presents several wks or months after fetal death with no expected features of pregnancy, a -ve pregnancy test and DIC. Resuscitate and refer urgently. P.560
Ectopic pregnancy Gestational sac implantation outside the uterus has ↑ and now occurs in ≈1 in 100 pregnancies in the UK. 96% implant in the Fallopian tube, 2% in the interstitial part of uterus, 1.5% intra-abdominally. The risk of heterotopic pregnancy (combined intrauterine and ectopic) is ≈1 in 4000. Importance Ectopic pregnancy is the commonest cause of maternal mortality in the first trimester. Diagnosis is frequently missed. Consider it in any young woman presenting with abdominal pain or vaginal bleeding, especially when combined with an episode of syncope. Risk factors Include anything which delays or limits normal transit of the fertilized ovum to the uterus: PID, pelvic surgery/adhesions, previous ectopic, endometriosis, assisted fertilization, IUCD, progesterone only pill, congenital genital anatomical variants, ovarian and uterine cysts/tumours. Note that although pregnancy is unusual after tubal ligation, when it does occur there is a relatively high chance (≈1 in 6) of it being an ectopic pregnancy. Pathology Implantation of the gestational sac in the Fallopian tube may have three results:

  • Extrusion (tubal abortion) into the peritoneal cavity
  • Spontaneous involution of pregnancy
  • Rupture through the tube causing pain and bleeding

Implantation in a uterine horn is particularly dangerous: pregnancy may reach 10-14wks before rupture. Exceptionally, intraperitoneal pregnancies may proceed almost to term. Symptoms The classic acute presentation is of sudden onset unilateral severe abdominal pain accompanied by a collapse/vasovagal episode and followed by mild, fresh vaginal bleeding. There is a background of amenorrhoea (usually ≈8wks). Shoulder tip pain (free intraperitoneal fluid irritating the diaphragm) and features of hypovolaemia occur with significant haemorrhage. Presentation is frequently atypical and more chronic: recurrent lower abdominal pain combined with slight irregular vaginal bleeding. The bleeding may be dark (like ‘prune juice’) as the decidua is shed. There may be no vaginal bleeding. Enquire about possible risk factors. Signs Look for hypovolaemic shock. If present, volume replacement must accompany full assessment. Abdominal tenderness is variable, ranging from mild to severe with peritonism. Cullen’s sign (discolouration around the umbilicus) is of historical interest only. Bimanual vaginal examination reveals tender adnexa and sometimes a mass, but may be deferred to a specialist (risk of ↑bleeding). Speculum inspection usually shows vaginal blood. Investigation Must not delay resuscitation and referral. Pregnancy test is almost always +ve, but serum ß-HCG levels are lower than expected for normal pregnancy. Transabdominal USS is useful if it demonstrates an intrauterine pregnancy or an adnexal mass. Frequently it does neither. Transvaginal USS may be better. P.561
Differential diagnosis

  • Threatened abortion—bleeding is usually more severe (p558).
  • Ruptured corpus luteum cyst—the corpus luteum supports pregnancy for the first 6-8wks. Rupture causes sudden peritoneal irritation, but rarely bleeds significantly.
  • PID (p546).
  • Trophoblastic disease (p562).

Treatment Give O2, insert two large (12 or 14G) cannulae, cross-match 6 units of blood, request Rhesus status. Resuscitate initially with crystalloid IV fluids as necessary. If suspected, refer urgently to the gynaecology team since sudden deterioration may occur. Significant haemorrhage requires urgent surgery. Check Rhesus and antibody status: anti-D Ig may be needed (p556). P.562
Vaginal bleeding in later pregnancy Gestational trophoblastic disease Occasionally, a fertilized ovum may form abnormal trophoblastic tissue, but no fetus. The pathological spectrum ranges from benign hydatidiform mole to invasive choriocarcinoma. Choriocarcinoma is relatively rare, affecting ≈1 in 40,000 pregnancies. Presentation Usually vaginal bleeding at 12-16wks, with passage of tissue which may resemble frogspawn. Often accompanying abdominal pain and sometimes pre-eclampsia or eclampsia. The uterus may be much larger than expected for dates. DIC may occur. Investigations USS shows ‘snowstorm’ and no fetus. Serum HCG is grossly↑. Management Obtain venous access, serum HCG, FBC, group and save, IV fluids/resuscitation and refer. Antepartum haemorrhage Bleeding after 20wks occurs in 2.5% of pregnancies. Abruptio placentae and placenta praevia are most likely causes, although other cervical or vaginal lesions may be responsible. Abruptio placentae Premature separation of the normally situated placenta affects ≈1% of pregnancies. It causes haemorrhage which may risk the fetus, depending on the extent of placental involvement and rapidity of separation. Risk factors:

  • pre-eclampsia
  • previous abruption
  • trauma (p568)
  • smoking
  • ↑parity

Presentation There is usually some vaginal bleeding (‘revealed haemorrhage’), but occasionally bleeding is limited to the confines of the uterus (‘concealed haemorrhage’). In either case, there may be much more utero-placental bleeding than is immediately apparent. There may be abdominal pain and tenderness. Abruptio placentae may precipitate labour. A large bleed can cause DIC or absent fetal heart sounds. Placenta praevia The placenta is situated wholly or partly over the lower uterine segment and cervical os. Risk factors Mother aged >35yrs, 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 labour. If placenta praevia is a possibility, do not perform digital or speculum vaginal examination. Vasa praevia Rarely, an abnormal fetal blood vessel may be attached to the membranes over the internal os. Haemorrhage may cause fetal exsanguination, usually during labour. P.563
Management of antepartum haemorrhage

  • Call an obstetrician immediately.
  • Give O2.
  • Obtain venous access (2 large bore cannulae) and resuscitate with IV fluids as necessary.
  • Send U&E, FBC, blood glucose, X-match, Rhesus and antibody status, Kleihauer test, clotting screen.
  • Monitor the fetus (cardiotocography).
  • USS locates the placenta, demonstrates the fetus and may show concealed haemorrhage.
  • Give anti-D Ig as advised by Blood Transfusion Service if Rhesus -ve (p556).

P.564
Abdominal pain in pregnancy Attempting to deduce the cause of abdominal pain can ordinarily be difficult: in pregnancy it is even more so. Some possible underlying diseases may be causing unseen fetal distress and can produce rapid maternal deterioration. Therefore, triage ahead, contact the obstetrician and resuscitate vigorously. Initial investigations usually include BMG, urinalysis, blood tests and USS. Vaginal bleeding accompanying abdominal pain implies a gynaecological or obstetric problem (p546). Remember, however, that the reverse is not necessarily true: ruptured ectopic pregnancy and concealed haemorrhage in abruptio placentae may present without vaginal bleeding. In later pregnancy, even if there is doubt as to whether the principal problem is obstetric or not, it is a good idea to involve the obstetrician at an early stage. Pregnancy related causes The following are considered elsewhere:

  • ectopic pregnancy (p560)
  • ‘red degeneration’ of a fibroid (p547)
  • gestational trophoblastic disease (p562)
  • abruptio placentae (p562)
  • onset of labour (p552)

Torsion, rupture or haemorrhage 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 fluid may complicate pregnancy involving uniovular twins. Pain and vomiting is accompanied by a large abdomen for gestation and an unusually mobile fetus. Pre-eclampsia Abdominal pain (particularly right upper quadrant pain) in pregnancy may reflect pre-eclampsia (p566). Check BP and urinalysis and refer urgently. Non-obstetric causes Urinary tract infection UTI is relatively common in pregnancy due to urinary stasis. Women are at particular risk if they have had previous UTI. Abdominal/loin pain and pyrexia with rigors indicate acute pyelonephritis. Send MSU, FBC and blood cultures and refer for IV antibiotics. Treat patients with asymptomatic UTI or cystitis without evidence of pyelonephritis with oralantibiotics (eg amoxicillin 250mg PO tds or a cephalosporin) and arrange GP follow-up when the MSU result will be available. When prescribing antibiotics in pregnancy, take care to avoid those drugs which arecontra-indicated (eg trimethoprim, tetracyclines—see BNF). Acute appendicitis Presentation in early pregnancy may be as classically described, but can be confused with ectopic pregnancy or rupture/torsion of an ovarian cyst. In later pregnancy, the point of maximal tenderness in acute appendicitis rises towards the right hypochondrium. Check BMG, serum amylase and urinalysis. Give analgesia and refer if suspected. P.565
Gallstones Pain from gallstones often presents for the first time in pregnancy.The presentation of biliary colic and cholecystitis is similar to that in the non-pregnant patient (p488). USS reveals stones and associated pathology. Give analgesia and refer: if possible, the patient will be treated conservatively. Acute pancreatitis Usually related to gallstones. There is a significant risk to mother and fetus. Presentation and treatment are as described on p486. Perforated peptic ulcer If suspected, obtain erect CXR with lead shield for the fetus. Resuscitate and refer (p489). Intestinal obstruction Usually follows adhesions from previous surgery. The diagnosis may not be immediately obvious: pain, vomiting and constipation may be initially attributed to pregnancy. These symptoms plus abdominal tenderness and high pitched bowel sounds suggest the diagnosis. An erect abdominalX-ray will confirm it, but this should only be requested by a specialist. P.566
Medical complications of pregnancy Pre-eclampsia and eclampsia This poorly understood vasospastic uteroplacental disorder affects 7% of pregnancies. It results in widespread systemic disturbance involving the liver, kidneys, coagulation and cardiovascular systems. Placental infarcts may occur and compromise the fetus. Pre-eclampsia = 2 or more of: hypertension (>140/90), proteinuria and oedema. Variant presentation: haemolysis, elevated LFTs, low platelets (HELLP syndrome) particularly affects the multigravida. Progression to eclampsia is heralded by: confusion, headache, tremor, twitching, ↑ reflexes. Visual disturbance and/or abdominal pain may occur. Eclampsia = onset of fits after 20wks (or fits in association with pre-eclampsia). Maternal mortality is 2%, perinatal mortality 15%. Management

  • Give O2 and crystalloid IVI 1-2mLs/kg/h.
  • Obtain FBC, uric acid, U&E, LFTs, clotting screen, ECG, fetal monitoring.
  • Refer all patients with BP>140/90 or proteinuria and oedema.
  • If there is evidence of impending eclampsia or patient commences to fit: call the obstetrician and anaesthetist, check BMG, control airway, give O2 and 4-6g magnesium sulphate slowly IV over 25mins, followed by a maintenance magnesium suphate 1-2g/h IVI.
  • Follow local advice regarding control of hypertension (eg labetolol 10mg slow IV bolus, followed by an IVI starting at 1-2mg/min, ↑as required).
  • Urgent delivery is a priority in eclampsia, both for mother and fetus.

Thromboembolic disease Pregnancy carries 5 × ↑risk and is a significant cause of maternal mortality. Extra risk factors Caesarian section, previous DVT/PE, ↑age, bed rest, GA. Only 50% of DVTs are clinically apparent, but ≈25% embolise. Therefore, adopt a high index of suspicion. USS is the safest initial investigation for DVT. PE presents with pain, dyspnoea, haemoptysis (p118). If suspected, obtain ECG, ABG and CXR (with lead shield for fetus). Give O2, load with 5000u IV heparin, then give 1000u/h continuous IVI (alternatively use LMWH in standard doses) and refer. Disseminated intravascular coagulation DIC may complicate a variety of obstetric problems: abruptio placentae, intrauterine death, missed abortion, amniotic fluid embolism, eclampsia, sepsis, trophoblastic disease. Clinical picture Widespread haemorrhage and microvascular occlusion. Obtain FBC, X-match, clotting screen, fibrin degradation products, fibrinogen, U&E and LFTs. Treatment Resuscitate with O2, IV fluids (according to CVP), blood transfusion and FFP. Refer urgently and consider urgent delivery and treatment of underlying disease. Diabetes mellitus Pregnancy encourages hyperglycaemia. IDDM in pregnancy may be more difficult to control and is associated with an ↑insulin requirement. DKA occurs relatively easily (p148). Other problems Thyrotoxicosis presents not infrequently in pregnancy. Pre-existing heart dis-ease worsens as blood volume and cardiac output↑: involve a specialist early. P.567
P.568
Trauma in pregnancy Background Principal causes are similar to those in the non-pregnant: road traffic collisions, falls and assaults. Contrary to popular opinion, the use of seat belts does ↓risk of serious injury in pregnancy. The ‘lap’ belt should lie over the anterior superior iliac spines. Anatomical considerations The following are worthy of consideration:

  • As the uterus enlarges it rises out of the pelvis with the bladder—both are at ↑risk of injury.
  • The size of the uterus and stretching of the peritoneum make abdominal assessment difficult.
  • The bony pelvis is less prone to fracture, but retroperitoneal haemorrhage may be torrential due to ↑vascularity.
  • Supine hypotension may occur and bleeding from lower limb wounds↑ due to ↑venous pressure.
  • The diaphragm is higher in pregnancy.
  • The pituitary doubles in size and is at risk of infarction in untreated hypovolaemic shock.

Physiological considerations Pregnancy is associated with dramatic changes in physiology:

  • Pregnant patents may tolerate up to 35% loss of blood volume before manifesting classic signs of hypovolaemic shock, largely at the risk of uteroplacental circulation.
  • The ↓functional residual capacity and ↑O2 requirement result in hypoxia developing more quickly.
  • There is an ↑risk of regurgitation of gastric contents.
  • Coagulation may be deranged or rapidly become so.

Injuries to the uterus, placenta and fetus Fetal injury Both blunt and penetrating trauma may damage the fetus. It is, however, more likely to suffer as a result of maternal hypoxia/hypovolaemia or placental abruption. Placental abruption Deceleration forces in blunt trauma may shear the inelastic placenta from the elastic uterus. Haemorrhage (maternal and fetal) may be significant and result in DIC. This may present with vaginal bleeding (much may be concealed internally), uterine tenderness or fetal distress. Uterine rupture This is relatively uncommon. Major rupture causes severe bleeding. The uterus and fetus may be felt separately. Amniotic fluid embolism Rare and with a poor prognosis. Presents with sudden collapse, dyspnoea, ↓BP, fitting and bleeding (from DIC). P.569
Approach to the injured pregnant patient Follow that outlined on p312, with the additional specific points: History

  • Determine gestation and any problems in this and previous pregnancies.

Examination

  • Involve an obstetrician early: examine vagina for bleeding or rupture of membranes.
  • Palpate for fundal height (mark skin), abdominal tenderness, uterine contractions.
  • Listen for fetal heart sounds and rate (Pinard or doppler probe).
  • Remember that head injury may mimic eclampsia and vice-versa.

Investigation

  • Check BMG, coagulation screen, Rhesus/antibody status and Kleihauer test.
  • Consider CVP monitoring (remembering the CVP is lower in pregnancy).
  • Monitor fetal heart (cardiotocograph)—the rate should be 120-160/min.
  • USS investigates fetal viability, placental injury and gestational age.
  • Do not withold essential X-rays, but do consider alternatives (USS or DPL). Seek senior advice. Remember that the greatest risks fromX-rays to the fetus are in early pregnancy. In later pregnancy, risks to the fetus may be outweighed by failure to identify injuries by not obtaining X-rays.
  • DPL—if indicated, use a supra-umbilical open approach (see p337).

Treatment

  • Give O2 and refer early.
  • If chest drains are required insert 1-2 intercostal spaces higher than usual.
  • Decompress the inferior vena cava by manually displacing the uterus to the left or by using a 15° right lateral (Cardiff) wedge, or if neck injury has been excluded, by nursing in left lateral position.
  • Treat fluid losses with aggressive IV fluid replacement.
  • An NG tube ↓risk of regurgitation and aspiration.
  • Remember tetanus prophylaxis (p396).
  • Consider anti-D immunoglobulin if the patient is Rhesus -ve.
  • Even if there is no overt maternal injury refer for fetal monitoringfor 4h.
  • Abdominal tenderness, hypovolaemia or fetal distress may require urgent laparotomy.
  • If the patient has a cardiac arrest, perform emergency Caesarian section if the patient is >24wks pregnant and 5mins has elapsed without output (see p570).

P.570
Cardiac arrest in pregnancy Rate Estimated in late pregnancy at ≈1 in 30,000. Causes CVA, PE, uteroplacental haemorrhage, amniotic fluid embolism, eclamptic fits and haemorrhage, anaesthetic problems and drug reactions, underlying heart disease. IHD is rarely implicated: the underlying rhythm is more commonly EMD than VF. Unfortunately, this is reflected in the poor prognosis. Remember the following physiological factors:

  • The airway is difficult to control (large breasts, full dentition, neck oedema and obesity)
  • ↑ aspiration risk (↓ lower oesophageal pressure, ↑intragastric pressure)
  • ↑O2 requirements in pregnancy, yet harder to ventilate (↓ chestcompliance)
  • Chest compression is awkward (flared ribs, raised diaphragm, obesity, breast hypertrophy)
  • Gravid uterus compresses inferior vena cava diminishing venous return
  • There are 2 patients: mother and fetus

Approach to resuscitation Follow the European Resuscitation guidelines for the management of cardiac arrest in adults (p44). The special situation of pregnancy mean that some additional points also apply:

  • Call urgently for help from an obstetrician and paediatrician.
  • Apply cricoid pressure (Sellick manoeuvre) at the beginning ofresuscitation and until the airway is secured.
  • Aim to secure the airway with a cuffed tracheal tube at an early stage.
  • Decompress the inferior vena cava by either manual displacement of the uterus to the left, or the use of sandbags or a special 15° right lateral (‘Cardiff’) wedge.
  • Consider and treat the cause (eg remember that hypovolaemic shock from unseen haemorrhage may respond to a large IV fluid challenge).
  • If there is no return of spontaneous circulation within 5mins perform a Caesarian section (providing the patient is >24wks pregnant).

Emergency Caesarian section Rationale After several mins of maternal cardiac arrest the best chance of survival for the fetus is to be removed from the now hostile hypoxic environment of the uterus. Caesarian section also benefits the mother by decompressing the inferior vena cava, resulting in ↑venous return. Procedure Continue closed chest compression and ventilation. Make a midline skin incision from pubic symphysis to epigastrium. Incise the underlying uterus vertically, starting 6cm above the bladder peritoneal reflection. Continue the uterine incision upwards to the fundus, through an anteriorly placed placenta if necessary. Speed is essential. Deliver the baby, holding it head down and below the level of the mother’s abdomen. Clamp and cut the umbilical cord. Resuscitate the baby (p614). P.571
P.572
Post-partum problems Physiology of the puerperium Within 24h of delivery uterine involution means that the fundus is level with the umbilicus. By 2wks the uterus should be impalpable. Uterine discharge (‘lochia’) gradually↓, but may last up to 6wks. An initially bloody discharge becomes yellow within 2wks. The external cervical os gradually closes so that after 1wk it no longer accepts a finger. Speculum examination will now reveal the typical parous os (see below). Post-partum haemorrhage Primary Haemorrhage >500mL in the first 24h is often related to retained placenta/clots. This, together with uterine inversion and amniotic fluid embolism are principally problems of the labour ward. Secondary Excessive fresh vaginal bleeding between 1 day and 6wks after a delivery affects ≈1% pregnancies. The most common cause is retained products of conception: uterine involution may be incomplete and USS may reveal the retained products. Other causes include intrauterine infection (see below), genital tract trauma, trophoblastic disease. Resuscitate appropriately for blood loss and refer. Severe bleeding may respond to IV oxytocin. Pyrexia Treat according to the underlying cause, which include the following:

  • pelvic infection (see below)
  • UTI
  • mastitis
  • chest infection
  • DVT
  • illness apparently unrelated to pregnancy/delivery

Pelvic infection Involves a significant threat: may be complicated by septicaemia, necrotizing fasciitis, DIC or septic PE. There is an ↑risk with: surgical procedures in labour, prolonged membrane rupture, internal fetal monitoring and repeated examinations. Features Uterine tenderness and subinvolution, pyrexia, offensive lochia, peritonitis. Send Vaginal swabs for culture, FBC, group and save, clotting screen and blood cultures. Resuscitate with O2 and IV fluids and refer. For septic shock, give IV co-amoxiclav (1.2g) and IV metronidazole (500mg), monitor CVP, consider inotropes and ventilation. Infected episiotomy wound —refer to obstetrician. Mastitis and breast abscess Mastitis is commonly due to Staph. or Strep. Send milk for culture and commence oral antibiotics (eg co-amoxiclav). Instruct patient to express and discard milk from the affected breast, but to continue breast-feeding from the other. Arrange GP follow-up. Refer patients with abscesses for surgical drainage by incision or the now preferred aspiration (p502). P.573
Psychiatric illness Rapid hormonal swings are responsible for elation being frequently replaced by tearfulness and anxiety (‘fourth day blues’). Less commonly (0.5% pregnancies) puerperal psychosis occurs. Those with a previous psychotic illness are at particular risk. Exclude sepsis and refer for psychiatric help. The patient may need to be compulsorily detained (p600). Thromboembolic disease A major cause of maternal mortality throughout pregnancy and the puerperium. Adopt a high index of suspicion and refer for investigation (p118).

Figure. Appearance of the cervical Os

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