Obstetrics and gynae Flashcards
(119 cards)
1
Q
heavy menstrual bleeding
A
Bleeding deemed prolonged or excessive according to the patient. Treatment guided by QOL/patient perception.
2
Q
Causes of vaginal bleeding
A
- Dysfunctional uterine bleeding (no organic pathology) - 60% presentations
- Systemic causes (endocrine, bleeding disorders, liver disease)
- Uterine and local causes (Palm coein) - adenomyosis, fibroids, polyps, infection, carcinoma
- Iatrogenic
- Pregnancy complications (consider in sexually active women)
- Trauma/heavy exercise
3
Q
What is the commonest cause of vaginal bleeding and how do you diagnose this?
A
Dysfunctional uterine bleeding
- diagnosis of exclusion in women of reproductive age (no underlying pathology)
4
Q
- 2 Types of Dysfunctional uterine bleeding
- and underlying pathophys
- type of endometrium on histology in each case
A
Ovulatory
- ? due to excessive prostacyclin production -> incr vasodilation and decr platelet aggregation in the context of a SECRETORY endometrium
Anovulatory
- Lack of ovulation -> no CL -> no progesterone -> endometrium continues to thicken under influence of unopposed oestrogen until it outgrows blood supply, then undergoes necrosis and shedding -> cycles are long and irregular
- PROLIFERATIVE endometrium
5
Q
Consequences of DUB if not managed
A
Fe deficient anaemia
Infertility (if anovulatory because no ovulation occurring)
6
Q
Endocrine causes of heavy menstrual bleeding
A
Thyroid disease Pituitary disease Adrenal disease PCOS Extreme changes in weight
7
Q
Bleeding disorders that can cause HMB
A
Von willebrand’s disease
Platelet function disorders
Factor 5/6/10 deficiency
8
Q
Pregnancy complications that can cause abnormal menstrual bleeding
A
miscarriage
ectopic pregnancy
9
Q
Iatrogenic causes of menstrual bleeding
A
Contraception:
- OCP
- Depot provera
- Implanon
- IUCD
Anticoagulation
Chemotherapy -> causes thrombocytopenia
10
Q
Fibroids
- What is another name for this?
- what is the incidence?
- Presentation
A
- Leiomyoma
- 20% women >30yo
Presentation
- Asymptomatic
- Heavy MB
- Irregular MB
- Pressure-like pain
- Obstruction of labour
11
Q
RF for fibroids
A
Nulliparity
Obesity
+ fam HX
12
Q
Mx of fibroid/leiomyoma
A
Only treat if symptomatic! Mx depends on symptoms
- Hormonal treatment can manage heavy/irregular MB
- Hysteroscopic resection if sub mucous
- Myomectomy (remove single specific fibroid)
- Embolisation (blood blood supply to single problematic fibroid)
- Ablation (U/S beam under MRI guidance destroys fibroid tissue)
- Hysterectomy if resistant to treatment
13
Q
local/ Uterine causes for abnormal MB
A
- Body of uterus:
Myometrium
- fibroids
- Adenomyosis
Endometrium
- polyps
- hyperplasia
- carcinoma
- endometritis (infx)
- Cervix
- cervical polyps
- carcinoma - Ovarian pathology
14
Q
Do you worry about polyps
A
Asymptomatic - generally found incidentally on imaging/hysteroscopy- but remove them for histology because can be MALIGNANT.
15
Q
What is adenomyosis
What are risk factors?
A
Endometrial glands found WITHIN myometrium (normal line the outside)
RF: middle aged (30s, 40s)
- multiparous women
16
Q
Presentation of adenomyosis
A
- HMB (bleeding of endometrial glands found WITHIN and lining endometrium + uterine expansion)
- Dysmenorrhoea (irregular menstrual bleeding)
- Bulky tender uterus (uterus enlargement -> incr SA -> incr bleeding)
17
Q
Investigations and management for suspected adenomyosis
A
USS and MRI (more sensitive)
Mx
- Hormonal treatment to induce amenorrhoea/reduce flow (IUCD etc, GnRH analogues)
- Hysterectomy
18
Q
Presentation of endometrial cancer
A
Post-menopausal bleeding
HMB
Irregular menstrual bleeding
19
Q
Risk factors of Endometrial carcinoma
A
Post-menopausal woman Unopposed oestrogen (HRT) Chronic anovulatory cycles Obesity PCOS Nulliparous Infertility \+ FHX HNPCC Tamoxifen (hormone therapy for breast cancer)
20
Q
Presentation of cervical cancer
A
Often asymptomatic but may have post-coital bleeding (after sex)
21
Q
How do you diagnose Endomettrial vs cervical cancer
A
Endometrial cancer
- Endometrial biopsy
Cervical cancer
- pap smear (although can be normal)/ regular HPV testing
- COLPOSCOPY!!!
22
Q
Blood supply to female pelvic visera
A
Ovarian artery/vein (from abdominal aorta) -> Ovaries, fallopian tubes, uterus
Uterine artery/vein (from internal iliac) -> uterus
Vaginal artery (from internal iliac) -> cervix and vagina
Pudendal artery (from internal iliac) -> clitorus, perineal muscles, inferior rectum
23
Q
What is contained within suspensory ligament of ovary?
A
Ovarian artery, vein, nerves, lymphatics
24
Q
inside what ligament does the uterine artery run?
A
The cardinal ligament /transverse ligament, connecting the cervix to the ischial spine
25
When cutting the transverse ligament as part of a hysteroscopy, what structure is endangered and what is it's relationship to this?
Risk injuring the ureters which run just under the uterine artery
26
Where do the ureters run in relationship to
- the common iliac artery
- the uterine artery
Ureters run:
- over the common iliac
- under the uterine artery
27
What ligaments support the ovary
Suspensory ligament (from ovary to pelvic wall)
Ovarian ligament (from uterus to ovary)
28
What structure is a remnant of the gubernaculum and what is it's anatomical path?
Round ligament
Runs from just lateral to ostia (fallopian tube entrance to uterus), through deep inguinal ring and inguinal canal, to labia majora
29
What is the order of parts of the fallopian tube?
Where are ectopic pregnancies most likely to arise?
Fimbria
Infundibulum (widest)
Ampulla (longest) - ectopics most likely here!
Isthmus (narrowest, just lateral to ostia)
30
What ligaments support the uterus?
Upper
- broad ligament
- round ligament
Middle
- transverse/cardinal ligament
- pubocervical lig
- uterosacral lig
31
What structures and muscles comprise the urogenital triangle
Bulbospongiosum (bulb of vestibule and greater vestibular gland) - surrounds clitorus, urethra, vagina)
Ischiocavernosum
Transverse perineal muscles
32
What muscles comprise the anogenital triangle?
Levator ani (pubo and ileo-coccygeus)
Anal sphincter
Transverse perineal muscle
33
What is the nerve supply to the perineum?
Pudendal nerve, S234
34
lymphatic drainage of female pelvic viscera
Lymphatic drainage is via the
iliac
sacral
aortic lymph nodes
NOTE: NOT inguinal
35
What is salpingitis?
| What can this result in if untreated?
Inflammation of uterine tubes by bacterial infection
Can result in scarring -> stricturing of tubes -> obstruction > infertility or ectopic pregnancy
36
Which pelvic floor muscle is most prone to injury during childbirth?
What is it's function? What can result when it is damaged?
Puborectalis due to its medial position
Attaches from body of pubis and forms a U-shaped around the anal canal
Contraction puts a 90deg kink in anal canal maintaining continence.
Relaxation leads to defecation.
Damage -> decal incontinence
37
Damage to which structure in childbirth is most likely to lead to prolapse of the vagina
Perineal body
38
What is a LLETZ procedure?
Large Loop Excision of the Transformation zone of the Cervix
Abnormal Pap smear and subsequent investigation with Colposcopy the surface of your cervix has shown changes or abnormal cells (dysplasia).
LLETZ aims to totally remove the abnormal cells from the cervix.
39
DDX intermenstrual bleeding or post coital bleeding
Consider local cause
- polyps
- infection
- IUCD
- uterine or cervical cancer
- perimenopausal (anovulation)
40
Questions to ask about abnormal bleeding (not including associated features)
When was menarche?
When was first day or last normal menstrual period?
How long do you bleed for?
Length of cycle - regular/irregular?
Flow - #pads/tampons per day; flooding; clots?
Duration of time experiencing those SX
Bleeding between periods or after intercourse?
41
Associated features to ask on history of abnormal bleeding (not including associated features)
Bleeding between periods or after intercourse?
Painful periods or pain with intercourse? Deep/superficial; always or recently
Faint/light headed/sweating/fatigue/palpitations -> anaemia
Pressure/frequency/distension -> fibroids/mass
Endocrine SX (weight changes, hair growth, acne) -> thyroid/PCOS
Easy bleeding/bruising -> bleeding disorder
Sexual partners, condom use, discharge, pelvic pain -> PID/endometritis/pregnancy
Last pap smear -> cervical cancer
Medications (incl contraception and blood thinners i.e. warfarin and aspirin)
42
DDX secondary dysmenorrhoea or deep dyspareunia
Endometriosis
adenomyosis
infection
43
What investigations would you perform for abnormal bleeding?
FBE, iron studies, BHCG
+/- Coags, PFA, CBA, vWF (? bleeding problem)
+/- FSH, LH, estradiol, androgen screen (?PCOS)
+/- TFTs (?thyroid disease), prolactin, LFTs
Imaging
- trans-vaginal USS (first line w pipelle)
Endometrial sampling:
Via pipelle in O/P (if + for malignancy, can refer patient straight to oncology without hysteroscopy D&C)
Any abnormality on USS or pipelle, proceed to:
Hysteroscopy, D&C is gold standard -> biopsy
44
What can USS assess in gynae.
What can it not detect?
Can assess
- uterine size, shape
- endometrial thickness
- adenomyosis
Cannot detect
- endometriosis
- adnexal mass
45
Risks of hysteroscopy D&C
Perforation
Infection
Gas embolism
46
Indications for endometrial sampling for abnormal bleeding
Woman >40yo
Women <40yo with any RFs for endometrial cancer
Persistent Sx
47
Treatment for abnormal bleeding
Treat any underlying causes (e.g.: thyroid)
1. Medical
- Anti PGE (NSAIDs, mefanamic acid/ponstan)
- Tranexamic acid (antifibrinolytic to reduce flow)
- Hormonal (COCP, depot provera, GnRH analogue)
- Mirena IUD
2. Surgical
- Endometrial ablation (+ tubal ligation)
- Hysterectomy (+/- oophorectomy)
48
What women are indicated for endometrial ablation
What women shouldn't this be used on?
Sx of abnormal bleeding
- perimenopausal ideally (NOT in women who want to become pregnant)
- endometrium can grow back but isn't as luscious as it was previously -> can lead to IUGR
49
What is the difference between a subtotal and total hysterectomy?
Subtotal - leave behind cervix
Total - take out cervix, body, fundus of uterus
50
What is the most common cause of teenager w menorrhagia?
What are other relatively common causes?
Anovulatory dysfunctional uterine bleeding (especially within first 18 months after menarche)
```
Bleeding disorder (10-20%)
PCOS, thyroid disorder
```
Pregnancy
Local uterine/cervical causes rare
51
what is metrostaxis?
What is the management?
Metrostaxis is acute blood loss that can lead to haemodynamic instability
MX
- IV fluids +/- transfusion
- High dose PGE in acute phase (every 2 hours until bleeding stops, then wean - note: stopping PGE suddenly can induce period)
- Mirena/embolism/hystectomy as long-term MX
52
What is dyschezia?
Pain w defecation
53
Mittelschmerz
Midcycle pain usually felt in iliac fossa due to ovulation
54
Causes of secondary dysmenorrhoea
```
Endometriosis
Adenomyosis
Intracavity mass (IUD, polyp, fibroid)
```
55
Dyspareunia causes
- Superficial pain (at introitus)
- deep pain (pelvic)
- midway pain
superficial
- thrush
- skin conditions
- vestibulodynia
Deep
- endometriosis
- adenomyosis
- adhesions
- ovarian cysts
Midway
- Pelvic floor spasm/exhaustion for chronic contraction
56
What is vestibulodynia and how do you diagnose it?
Central sensitisation at entrance to vagina = pain with non-noxious stimuli
Diagnose with cotton-bud prodding (does it reproduce the same pain felt with sex)
57
Presentation of endometriosis
Cyclical pain: dysmenorrhoea, mid cycle pain, premenstrual pain
Pain on void/defecation w period
Provoked pain (pain w sex, tampon insertion, vaginal examination)
Infertility
Asymptomatic
58
Diagnosis of endometriosis
Clinical presentation (60-70% sensitivity)
USS can help detect cysts of endometriosis (positive if cysts are present in 2 consecutive USS, 6 weeks apart)
Or MRI
Laparoscopy is gold standard (matchstick spots)
59
Common sites for endometriosis
Pouch of douglas
Uterosacral ligament/fold
Side walls of ovaries and pelvis
60
Exam findings for endometriosis
```
Lower abdo tenderness
Tenderness on PV (lateral fornices)
Palpable adnexal mass (endometrioma = cyst)
Palpable vaginal nodule/thickening
Fixed uterus (adhesions)
```
61
MX of endometriosis
Do nothing (SX aren't severe, don't impact QOL)
Pain relief/analgesia
Hormonal (OCP, progestins, GNRH analogues)
Surgery
- endometrial ablation or excision
- hysterectomy
62
MX of the infertility associated w Endometriosis
```
Remove hydrosalpinges
Remove endometriomas >3cm
Remove all 'E'
Early move to IVF
Plan pregnancies earlier (<35)
```
63
Classic presentation (SX and signs) of adenomyosis
SX
- menorrhagia
- dysmenorrhoea
Signs
- bulky uterus
- uterus tender on bimanual palpation
64
What investigations to diagnose Adenomyosis?
USS - spec/sens in the 80s%
Hysterectomy -> histology is gold standard
65
Mx of adenomyosis
Tx is about QOL
Do nothing
Medication
- Analgesia (NSAIDs)
- Hormones (OCP, progestin, GNRH analogues)
- Mirena
Surgical
- hysterectomy
- myomectomy
- ? endometrial ablation
66
What is the perceived cause/pathophys behind primary dysmenorrhoea?
High levels of prostaglandins -> incr uterine contractions -> myometrial angina -> pain
67
Treatment primary dysmenorrhoea
Do nothing
Analgesics - NSAIDs
Hormones (OCP, progestins, GnRH analgoes)
Mirena IUD
Hysterectomy once completed family (radical)
Acupuncture
Smooth muscle relaxants: nifedipine, GTN, buscapan (can cause postural hypotension! LOC etc)
68
What is the average age range for menopause?
What causes menopause?
45-55
Primordial follicles stores are exhausted by atresia and ovulation (accelerated loss after age of 37)
69
What is perimenopause? What is the underlying pathophys?
Onset of menopausal SX up to a year after the final menstrual period
Pathophys:
- Gradual rise in FSH
- Fluctuations in estrodial and progesterone (declining levels overall due to lack of ovulation)
- Decr ovarian inhibit B released from ovarian granulosa cells
70
What factors influence age of onset of menopause if any?
Smoking
Hysterectomy
-> earlier age of onset
71
Consequences of menopause
why do these symptoms develop?
Short-term
- vasomotor symptoms (hot flushes and night sweats)
- vaginal dryness and atrophic vaginitis
- sleep/mood disturbance/ reduced libido
Medium to long term
- bone loss and osteoporosis
Due to decr oestrogen (E2 - estradiol)
72
How does menopause lead to osteoporosis?
E2 normally suppresses bone reabsorption by suppressing osteoclast activity so E2 deficiency
- increases bone resorption
- increases renal Ca excretion
73
Prevention of osteoporosis
Diet - incr Ca intake
Reduce alcohol and smoking
Vitamin D
Weight-baring exercises,
74
Risk factors for osteoporosis
```
Prolonged steroid therapy
Premature menopause
Malabsorption
CLD
Hyperparathyroidism
```
75
What is premature menopause?
what risks are associated?
Menopause before 40 years
Incr risk of
- CV disease
- osteoporosis
- depression
76
Causes of premature menopause
Iatrogenic (chemo/radiotherapy; surgery)
Premature ovarian failure (idiopathic spontaneous ovarian failure)
Rare causes:
Galactosaemia
Turner syndrome
Fragile X syndrome
77
Diagnosis of pre-mature menopause
- > 4 months amenorrhoea before age 40
- exclude causes of secondary amenorrhoea (prolactin, TFTs, betaHCG)
- HIGH FSH on 2 occasions 1 month apart
78
What is HRT?
How can it be given?
```
hormone replacement therapy used in menopause for SX relief.
Contains oestrogen (treats SX and progesterone (protects against endometrial cancer)
```
Can be given as:
- tablets
- patches
- gel (estradiol only for tx of vaginal dryness)
- intrauterine (mirena)
79
Benefits vs risks of HRT
Benefits:
- effective relief of menopausal SX
- reduces loss of bone density and risk of fractures (if >60)
- improves QOL
Risks:
- Incr VTE and stroke
- Incr risk CVD
- Incr risk of breast cancer if use >5years (progesterone on breast)
- Incr risk of endometrial cancer (unopposed oestrogen)
80
Non-hormonal SX relief for menopause
Gapapentin
Clonidine
SSRI/SNRI
81
CI to HRT
```
Personal HX breast cancer
HX VTE or FHx thrombophilia
CV of CHD
Active liver disease (risk of cholecystitis)
Uncontrolled HTN
```
82
SX of atrophic vaginitis
Vaginal dryness, discomfort, pruritus, dyspareunia, UTI, urgency
83
When is HRT indicated?
Moderate to severe menopausal SX only, used at lowest dose and for shortest duration possible in younger women (<51)
84
What is Tibolone?
Synthetic steroid w weak oestrogen, progestogen and androgenic action
Treats menopausal SX (vasomotor SX, libido and vaginal lubrication)
85
Delancey levels of pelvic support
1:
- Cardinal-uterosacral ligament complex
- supports upper vagina, cervix
2:
- Endopelvic fascia
- bladder, middle vagina, rectum
3:
- fusion of vagina to perineal membrane and body
- supports lower vagina, urethra, anus
86
Most common cause of pelvic prolapse
Other causes
1. Damage to elevator and due to childbirth (stretching/trauma)
2. Age
3. Menopause
4. Previous surgery to correct pelvic organ support defects
5. Hysterectomy (-> vault prolapse)
6. Congenital defects (collagen defects)
7. Incr intra-abdominal pressure (Straining/heavy lifting/chronic cough and constipation)
8. Obesity/smoking/diabetes
87
Types of prolapse
Anterior vaginal wall descent = cystocele
Apical descent = Uterine/vaginal vault prolapse +/- enterocoele
Posterior vaginal wall descent = rectocele
Procidentia = down and out prolapse
Urethral or rectal prolapse
88
what is an enterocoele?
Portion of the small bowel extends into the pouch of douglas
89
What procedure can predispose to an enterocoele?
TO a cystocoele?
1. Burch colposuspension
| 2. sacrospinous suspension
90
What serotypes of HPV cause genital warts?
where is the most common place for HPV genital warts in women?
What are their clinical importance?
types 6 and 11
vulval warts
They are surrogates for exposure to and carriage of oncogenic types HPV 16 and 18 so requires regular pap smears!
91
Treatment for genital warts
Topical cream (ex: Imiquimod cream)
Non-responders -> diathermy or laser under anaesthesia
92
What is bartholinitis?
It is possible for the Bartholin's glands (secrete mucus to lubricate vagina) to become blocked and inflamed resulting in pain -> Bartholin's cyst -> A Bartholin's cyst in turn can become infected and form an abscess.
Red and tender swelling beneath the posterior part of labia majora
93
Leucorrhoea
Non-Infective, non-bloodstained physiological vaginal discharge
- diagnosis of exclusion (endocervical swab to exclude potential pathogens such as chlamydia or gonorrhoea or vaginal smear to exclude candida, bacterial vaginosis, chlamydia)
94
3 common pathological causes of abnormal vaginal discharge
1. trichomonas vaginalis = trichomoniasis (vaginal itching and irritation + profuse sometimes green frothy discharge)
2. Candidiasis (severe vulvovaginal irritation assoc w thick cheese discharge)
3. Bacterial vaginosis (no SX or thin greyish discharge w fishy smell)
95
Barriers to ascending vaginal ifetion
Thick cervical mucus
Acidic vaginal secretions
Shedding of endometrium monthly
96
How might infection be introduced into upper genital tract?
Sexually transmitted
Instrumentation (IUD insertion, gynae procedure such as D&C, termination of pregnancy)
Disruption of normal cervical barrier
following miscarriage, delivery or gynaecological surgery
HAem spread is rare
97
What is PID? How does it present?
What main organisms cause this?
Infection of more than one pelvic organ
Presentation:
Severe bilateral lower abdo tenderness and pain
Guarding
Cervical excitation
Fever +/- rigors
Cl -> mucopurulent discharge, dysuria, inter menstrual bleeding
N.Gon-> dysuria, frequency, purulent discharge
- Cl. trachomatis
- Neisseria gonorrhoea
98
SX of chlamydia vs gonorrhoea cervical infection
Both can be symptomless
Cl -> mucopurulent discharge, dysuria, inter menstrual bleeding
N.Gon-> dysuria, frequency, purulent discharge -> can spread down to bartholin's gland or up to endometrium and fallopian tubes
99
Diagnosis of PID
Laparoscopy or TV USS (less invasive) is diagnostic
endocervical and urethral swabs for N.G MCS
Urine and endocervical swab for Cl.Trach PCR
100
Long term effects of PID
Damage and scarring to fallopian tubes -> tube strictures
Incr risk of infertility
Incr risk ectopic pregnancies
101
How can chronic PID present?
Pyosalpinx
Hydrosalpinx
Chronic tuba-ovarian abscess
Chronic pelvic cellulitis
102
Symptoms of pelvic organ prolapse
- Asymptomatic
- Protruding bulge from vaginal opening
- Pelvic pressure/backache
- Ulceration/bleeding from prolapsed vaginal skin
- Difficulty urinating/defecating
- Incontinence of urine/faeces
103
Treatment of pelvic organ prolapse
1. None
2. Conservative
- Physic: Pelvic floor exercises
- Oestrogen replacement
- Lifestyle changes
- Pessary (supporting vaginal device)
3. Surgery
104
Pessary
What is it?
SEs?
Supporting vaginal device made from inert material (silicone)
Restore pelvic organ to normal position
SE: Can cause UTIs, vaginal infections, vaginal discharge/bleeding/erosions if in for a long time.
105
What are the surgeries called to fix:
1. Cystocoele
2. Rectocele
3. Uterine prolapse
4. Vault prolapse
1. -> anterior colporrhapy
2. -> Posterior colporrhapy
3. Vaginal hysterectomy or vag/abdo hysteropexy
4. Sacrospinous fixation
Abdominal sacral colpopexy
106
What is a McCall culdeplasty?
Repair of enterocoele - re-support using uterosacral cardinal ligaments
107
What is an abdominal sacral colpopexy?
Surgical repair of vault prolapse where vagina and uterus and re-attached to sacrum using mesh
108
Preventative strategies against PO prolapse
Avoid difficult vaginal deliveries
Avoid forceps which damage the pelvic floor
Education post delivery about exercise ad physio to optimise pelvic floor strength
Avoid heavy lifting
Weight loss
Quit smoking
109
Treatment of PID
§ Cephalosporins (cefriaxone IM) and azithromycin (oral) for gonorrhoea
§ Metronidazole to cover anaerobes (trichomonas)
§ Doxycycline for chlamydia
□ Check they aren't pregnant!
§ If she has a tuboovarian abscess, will need IV antibiotics
□ Don't usually drain these abscesses because drainage causes more harm than good
110
Causes of PPH
4 Ts
Tone: uterine atony, distended bladder.
Trauma: lacerations of the uterus, cervix, or vagina.
Tissue: retained placenta or clots.
Thrombin: pre-existing or acquired coagulopathy.
111
What causes late decelerations?
FEtal hypoxia and acidosis, usually due to
reduced uteroplacental blood flow: causes include...
Maternal hypotension
Pre-eclampsia
Uterine hyperstimulation
112
What does sinusoidal CTG pattern indicate?
Severe foetal hypoxia
Severe foetal anaemia
Foetal/maternal haemorrhage
113
What are variable decelerations caused by?
They are most often seen during labour and in patients’ with reduced amniotic fluid volume.
Variable decelerations are usually caused by umbilical cord compression¹:
114
What do shoulders of deceleration indicate?
“shoulders of deceleration“.
| Their presence indicates the foetus is not yet hypoxic and is adapting to the reduced blood flow. Reassuring feature
115
Conservative management of variable decelerations
Position change
IV fluids
Decrease syntocinin infusion rate.
116
What are accelerations?
Accelerations are an abrupt increase in baseline heart rate of >15 bpm for >15 seconds.
The presence of accelerations is reassuring.
117
What is normal variability?
| what is reduced variability? absent?
6-25.
Reduced <=5
Absent <=3
Non reassuring if >45-60min duration
118
What causes reduced variability?
Reduced variability caused by:
1. fetal seeing (last <60min)
2. maternal sedatives (opiates / benzodiazepines / methyldopa / magnesium sulphate)
3. Foetal acidosis (due to hypoxia) – more likely if late decelerations are also present
4. Foetal tachycardia
5. Prematurity – variability is reduced at earlier gestation (<28 weeks)
6. Congenital heart abnormalities
119
Causes of prolonged severe bradycardia are
```
Prolonged cord compression
Cord prolapse
Epidural & spinal anaesthesia
Maternal seizures
Rapid foetal descent
```
