Antenatal Obstetrics 3 Flashcards
1
Q
How much does hypertension affect pregnancies?
A
- Pregnancy induced hypertension (PIH) affects 6-7% of pregnancies.
- Chronic hypertension complicates 3-5% of pregnancies (more common due to an older pregnant population).
2
Q
Pathology of hypertension in pregnancy??
A
• BP is directly related to systemic vascular resistance and cardiac output and follows a distinct course during pregnancy:
- ↓ in early pregnancy until 24 weeks due to ↓ in vascular volume.
- ↑ after 24 weeks until delivery via an ↑ in stroke volume.
- ↓ after delivery but may peak again 3-4 days post-partum.
3
Q
Definition of PIH? Risks? When does it resolve?
A
• PIH = hypertension (>140/90mmhg) when >20w gestation, during labour or puerperium in the absence of proteinuria or other markers of pre-eclampsia.
- At ↑ risk of developing pre-eclampsia (↑ with earlier onset HTN).
- BP usually returns to the pre-pregnancy limits within 6 weeks of delivery
4
Q
Definition of chronic hypertension in pregnancy? Risks?
A
• Chronic = pregnant women who have a high booking BP (130-140/80-90 or more) are likely to have chronic HTN.
- ↑ risk of developing pre-eclampsia.
5
Q
Define post-partum hypertension?
A
• Post-partum = new HTN which arises in the post-partum period.
- BP peaks on the 3rd – 4th day post-partum
6
Q
Secondary causes of HTN?
A
- Renal disease (e.g. polycystic disease, renal artery stenosis or chronic pyelonephritis)
- Diabetes
- Cardiac disease (e.g. coarctation of the aorta)
- Endocrine causes (e.g. Cushings, Conns or rarely phaeochromocytoma)
7
Q
Symptoms, risks of HTN in pregnancy?
A
• Symptoms are often absent - Fundal changes, renal bruits and radiofemoral delay should be excluded. • Women with chronic HTN are at risk of: - Superimposed pre-eclampsia. - Fetal growth restriction - Placental abruption
8
Q
Investigations in hypertension in pregnancy?
A
• Urinalysis – look for protein.
• Bloods – FBC, U&Es, urate, LFTs and clotting.
- These would be expected to be normal if essential HTN in pregnancy (unless there was a secondary cause of the HTN).
• USS
• Investigations for underlying cause (e.g. CXR, ECG, 24h urine collection for creatinine and for catecholaemines [if phaeochromocytoma is clinically suspected]).
9
Q
When is hypertension an emergency in pregnancy?
A
• BP of >160/110 in pregnancy is medical emergency
10
Q
Management of PIH? Mild/moderate/severe?
A
Secondary care
If mild (140-149/90-99)
Weekly urine and BP
4 weekly foetal growth scans
If moderate (>150/100) Biweekly BP and urine
If severe (>160/110)
Admit to hospital
Measure BP QDS and check urine daily
FBC, U&E, AST/ALT, bilirubin at presentation and weekly
If not stabilised on oral treatment – aim for delivery 37 weeks unless pre-eclampsia
11
Q
Management of PIH during labour and after?
A
o During Labour
Monitor BP hourly, if abnormal – operative delivery
o Review at 2 and 6 weeks, if treatment still needed refer to specialist
12
Q
Antenatal management of chronic hypertension?
A
Change drugs over to labetalol/methyldopa before conception
Aim for <150/90
Aspirin 75mg PO daily
Admit if >160/110
Foetal USS every 4 weeks from 28 weeks to assess growth, fluid volume, Doppler
• If abnormal, arrange CTG
Induction of labour around EDD
13
Q
Perinatal management of chronic hypertension?
A
Monitor BP hourly & regularly post-natally
Oxytocin alone at 3rd stage of labour (Ergometrine causes severe hypertension)
Avoid methyldopa postnatally – psychiatric complications
14
Q
What are the problems with hypertensive drugs and which are used in pregnancy?
A
o ACEi are teratogenic and affect foetal urine production.
o β-blockers are associated with ↓ birth weight and used rarely.
o Labetalol is first line choice.
o Methlydopa/Nifedipine is second line
15
Q
Definition of pre-eclampsia?
A
o BP >140/90 after 20 weeks with 1 or more + proteinuria
16
Q
Pathology of pre-eclampsia?
A
- Failure of trophoblastic invasion of spiral arteries leaving them vasoactive
- Endothelial cell damage + exaggerated maternal inflammatory response
- Vascualr hyperpermeability, thrombophilia and hypertension which may compensate for reduced flow of uterine arteries
17
Q
Sequelae of pathology of pre-eclampsia?
A
a) Increased vascular resistance - HTN
b) Increased vascular perm - proteinuria
c) Reduced placental flow - IUGR
d) Reduced cerebral perfusion (maternal) - eclampsia (maternal)
18
Q
Classifying pre-eclampsia?
A
Mild
Proteinuria + BP 140-160
Severe
Proteinuria + BP >160 before 32 weeks or with maternal complications
19
Q
How common is pre-eclampsia?
A
5% in nulliparous women, pts with pre-existing HTN are x6 more likely to get pre-eclampsia
20
Q
Risk factors for pre-eclampsia?
A
1) Nulliparity
2) Prev Hx
3) Maternal age (>40 or teen)
4) Twins
5) BMI >35
6) Molar preg
7) Pre-existing hypertension, DM
8) Diabetes
9) Autoimmune disease
21
Q
Symptoms of pre-eclampsia?
Signs of pre-eclampsia?
A
Symptoms - Asymptomatic - Severe Headache - Drowsy - Visual disturbances (blurring, flashing lights) - N/V - Epigastric pain – at late stage - Oedema – face, hands and feet Signs HTN= 1st sign (late), proteinuria, oedema, confusion, clonus
22
Q
Diagnosis of pre-eclampsia?
A
- BP >140/90
- Urinalysis: Proteinuria 1+ or more
23
Q
Secondary diagnosis of pre-eclampsia?
A
- Urine MSU M,C&S = proteinuria >0.5g/L (exclude infection by urine culture)
- Urine PCR >30 diagnostic
24
Q
Monitoring antenatally in pre-eclampsia?
A
- BP
- Serial FBC (rapid decline in platelets due to platelet aggregation suggests impending HELLP or DIC)
- Serial U&E (raised creatinine and uric acid)
- LFTs – prolonged APTT&PT
- Clotting and G&S
- Foetal USS surveillance (CTG or Doppler)
25
Referring pre-eclampsia?
o BP >140/90 with proteinuria 1+ or more
o Systolic >160
o Diastolic >110
o Any signs of pre-eclampsia
26
Preventative measures in pre-eclampsia management?
Aspirin from 12 weeks
27
Management of pre-eclampsia?
- Admission to hospital (>140/90 + 1+ proteinuria, signs of pre-eclampsia)
- CTG at diagnosis and repeat if change in foetal movements, PV bleeding, abdominal pain
- IOL at 37/40 weeks
28
Management of mild pre-eclampsia?
o BP QDS
o Monitor U&E, FBC and LFTs 2x a week
o Foetal growth scans every 2 weeks
29
Management of moderate pre-eclampsia?
o PO labetalol (Aim <150/100, diastolic >80) (alternatives: nifedipine/methyldopa)
o BP QDS
o Monitor U&E, FBC and LFTs 3x a week
o Foetal growth scans every 2 weeks
o BDS CTG
30
Management of severe pre-eclampsia?
o PO labetalol (Aim <150/100, diastolic >80) (alternatives: nifedipine/methyldopa)
o Senior help - may need IV labetalol, fluid restriction
o Prophylactic MgSO4
o Steroids for lung maturation
o Deliver if >34 weeks (if <34 weeks, deliver within 24-48 hours)
o BP QDS, monitor U&E, FBC and LFTs 3 times a week
31
Delivery in pre-eclampsia?
* Deliver mild by term
* Deliver mod/severe >34-36 weeks if poss
* Deliver if maternal comps or foetal distress- whatever the gestation
* Pre-eclampsia only cured by delivery
32
Post-natal management of pre-eclampsia?
- BP QDS when in hospital
- FBC, LFT and U&E 72h after birth
- Measure BP 1-2 days for up to 2 weeks when transferred to community care, review at 2 weeks and 6 weeks (urine dip done)
33
Maternal complications of pre-eclampsia?
- Eclampsia (tonic-clonic seizures resulting from cerebrovascular vasospasm)
- Haemolysis, elevated liver enzymes, low platelet count (HELLP)
- CVAs (cerebral haemorrhage)
- Liver/renal failure
- DIC
- Pulmonary oedema
34
Foetal complications of pre-eclampsia?
- IUGR
- Morbidity and mortality
- Placenta abruption
- Pre-term birth
- Hypoxia
35
When does pre-eclampsia resolve?
Cured by delivery
36
What is eclampsia?
- Obstetric emergency
- Tonic-clonic seizures + pre-eclampsia
- Occurs in 1% of pregnancies with pre-eclampsia
37
When do seizures occur in eclampsia?
```
o Antenatally = 38%
o Intrapartum = 18%
o Postnatally (usually within the first 48 hours) = 44%
```
38
Management of eclampsia?
o Senior help (call for help)
o Airway
o Breathing (15L/m NRM)
o Circulation and IV access (Bloods - FBC, U&E, LFT & 2 wide bore cannula in ACF)
o Continuous monitoring of maternal O2 sats and BP
o MgSO4 4g IV over 5-10 mis, further 2g bolus (then IVI)
IV calcium gluconate ready for MgSO4 toxicity
Diazepam if repeated seizures
o If >160/110, use labetalol IV or nifedipine
o Consider steroids (dex) for lung maturity
o Restrict fluids to 80ml/hr
o Continuous foetal CTG
o Deliver once stable, LSCS quickest method as IOL takes a while
39
Managing hypertension in eclampsia?
o If >160/110, use labetalol IV or hydralazine IV
40
Monitoring during eclampsia management?
o Catheterise hourly urine output
o HR, BP, RR and O2 sats every 15 mins
o FBC, U&E, LFTs, creatinine and clotting every 12 hours
41
What is HELLP syndrome?
Serious complication regarded as a variant of severe pre-eclampsia which manifests with haemolysis (H), elevated liver enzymes (EL) and low platelets (LP)
42
Epidemiology of HELLP syndrome?
- Incidence = 5-20% of pre-eclamptic pregnancies.
- Materinal mortality = ~1%
- Perinatal mortality = ~10-60%
43
Symptoms and signs of HELLP?
- Syndrome is usually self-limiting but permanent liver or renal damage may occur.
- Symptoms include:
• Epigastric or RUQ pain
• N&V
- Signs include:
• Tenderness RUQ
• increased BP and other features of pre-eclampsia
• Dark urine (due to haemolysis)
44
What complications of HELLP syndrome?
- Eclampsia may co-exist
| - DIC, liver failure and liver rupture may also occur
45
Management of HELLP syndrome?
* As for eclampsia and delivery is indicated
| * If HELLP syndrome - consider high dose steroids
46
Glucose metabolism changes in pregnancy?
o Insulin requirements increase throughout pregnancy and are maximal at term.
o A normal woman can increase the amount of insulin she produces to counteract diabetogenic hormones (human placental lactogen, cortisol, glucagon, oestrogen and progesterone) to maintain her blood sugars at 4-4.5 mmol/L.
o Diabetic women are unable to do this and need close monitoring of the blood sugars for good control.
47
Effect of diabetes on pregnancy?
- Increased foetal and neonatal morbidity and mortality.
- Foetal hyperglycaemia - leads to hyperinsulinaemia through β-cell hyperplasia in foetal pancreatic cells.
- Insulin in the foetus acts as a growth promoter. The net effect is therefore macrosomia, organomegaly and increased erythropoiesis.
- Foetal polyuria causes polyhydraminos.
- Neonatal hypoglycaemia.
- Surfactant deficiency occurs through reduced production of pulmonary phospholipids – RDS
48
Effect of pregnancy on diabetes?
- Ketoacidosis
- Retinopathy:
There is a 2x ↑ risk of development or progression of existing disease
All diabetic women should have assessment for retinopathy in pregnancy, proliferative retinopathy requires treatment
- Nephropathy:
Affects 5-10% of women.
Renal function and proteinuria may worsen during pregnancy
- Ischaemic heart disease:
Pregnancy increases cardiac workload
49
Optimal glycaemic control during pregnancy?
o Aim for normoglycaemia.
o Aim FBG 3.5-5.9mmol/L, 1hPPG <7.8mmol/L
o HbA1c <6.5%
o There is increased risk of miscarriage and congenital abnormalities with poor control.
o Monitor glucose at least 4x a day, usually before meals but post-meal glucose may give tighter control.
50
How to assess severity of diabetes antenatally?
o HTN
o Retinopathy (funoscopy, ophthalmology assessment)
First clinic appointment and 28 weeks
o Nephropathy (U&E, urinalysis, urinary protein:creatinine ratio, 24 hour urine for protein, creatinine clearance).
o Neuropathy (clinical assessment)
o Cardiac disease
51
Antenatal education in pre-existing diabetes?
o Ensure understanding of effects of hyperglycaemia on fetus and the need for tight control.
o Instruct to inform doctor as soon as pregnancy confirmed.
o Some drugs need stopping (e.g. ACEi)
52
Antenatal general advice in pre-existing diabetes?
o Stop smoking
o Optimize weight (aim for a normal BMI)
o Minimise alcohol (max 1-2 units twice/week)
53
Antenatal medication in pre-existing diabetes?
- Aspirin
o Take 75mg daily from 12 weeks onwards to reduce risk of pre-eclampsia
- Folic acid:
o ↑ risk of neural tube defects, so start on 5mg folic acid.
- Rubella status:
o Offer vaccination if not rubella immune.
54
Antenatal contraception in pre-existing diabetes?
o Ensure effective contraception until good control achieved and pregnancy desired
55
When to refer pregnant mother with pre-existing diabetes?
Specialist diabetic antenatal consultant clinic
56
Other antenatal care needed with diabetic mother?
- Foetal echo at 18-20 weeks
| - Foetal growth scans every 4 weeks from 28 weeks
57
Delivery of pregnancy with pre-existing diabetes?
• Timing of delivery:
- Elective delivery by induction at 38-39 weeks (40 weeks for GDM)
- Delivery should be sooner if complications occur
- Corticosteroids given in premature
• Mode of delivery:
- Vaginal is preferred.
58
Labour of pregnancy with pre-existing diabetes?
- Continuous electronic fetal monitoring
- Avoid hyperglycaemia
- Medications
o Use sliding scale if DM on insulin, or CBG >7mmol/L
o Aim for glucose 4-7
o Insulin needs fall as labour progresses and immediately postpartum
o Stop infusion at delivery if T2 or GDM not on insulin
o IV fluids should always be given with sliding scale
Stable situations = 5% dextrose
High blood glucose = normal saline
- Avoid maternal hyperglycaemia → causes fetal hypoglycaemia.
- If steroids are given for threatened preterm labour monitor glucose closely as hyperglycaemia should be anticipated
59
Postpartum care of pregnancy with pre-existing diabetes?
• Halve the sliding scale initially.
• Change back to SC insulin when eating and drinking.
• Start with the pre-pregnancy dose of SC insulin.
• If this is not known, it is roughly half the last dose
• Aim for a BM 4-9 mmol/L in the postpartum period.
• Encourage breast-feeding.
- Avoid oral hypoglycaemic drugs if breast-feeding, insulin is safe.
• Baby needs early feeding and glucose monitoring.
60
Maternal complications of pregnancy with pre-existing diabetes?
- UTI
- Recurrent vulvovaginal candidiasis
- Pregnancy-induced hypertension/pre-eclampsia
- Obstructed labour
- Operative deliveries (CS and assisted vaginal deliveries)
- ↑ retinopathy (15%)
- ↑ nephropathy
- Cardiac disease
61
Foetal complications of pregnancy with pre-existing diabetes?
- Miscarriage (in diabetes with poor control)
- Congenital abnormalities (in diabetics with poor control):
- Preterm labour
- Polyhydramnios (25%)
- Macrosomia (25-40%)
- IUGR
62
Neonatal complications of pregnancy with pre-existing diabetes?
- Polycythaemia
- Jaundice
- Hypoglycaemia
- Hypocalcaemia
- Hypomagnesaemia
- Hypothermia
- Cardiomegaly
- Birth trauma:
- Shoulder dystocia, RDS, Erbs
63
Where is GDM more prevalent?
• More prevalent in women of South East Asian, Mediterranean and Afro-Caribbean origin.
64
Risk factors for GDM?
- Family history of 1st degree relative with diabetes.
- Obesity (BMI >30)
- Previous large baby (>4kg)
- Previous unexplained still birth
- Previous gestational diabetes
- Polycystic ovarian syndrome
- Polyhydramnios in this pregnancy
- Glycosuria on two or more occasions in this pregnancy.
- Abnormal timed random glucose
>5.5mmol/L fasting or >2 hours after food.
>7.0 mmol/L <2 hours after food
65
Symptoms and signs of GDM?
* Recurrent infections
* Persistent glycosuria
* Large for date foetus with macrosomia or polyhydramnios
66
When to screen for GDM?
```
o 1st degree relative
o Previous baby >4.5kg
o BMI>30
o Ethnicity (South Asian, Caribbean, Middle East)
o Previous GDM
```
67
Diagnosis of GDM?
• 75g 2-hour OGTT soon after booking, 24-28 weeks and repeated at 34 weeks (if other two negative)
Overnight fasting (8 hours minimum – water only, no smoking)
75g load in 250-300mL water.
Plasma glucose measured fast and at two hours
68
Results of OGTT indicative of GDM?
- Diabetic results
Fasting glucose ≥5.6 mmol/L
2-hour glucose ≥7.8 mmol/L
- Only one value has to be abnormal to make the diagnosis
69
Antenatal monitoring in GDM?
o USS & cardiac echo
o Foetal growth every 4 weeks from 28-36
o Glucose levels
70
Immediate management of GDM?
o If diagnosed, offer review with diabetes and antenatal clinic within 1 week
o Inform GP
o Information
Implications of diagnosis for her and baby (DVLA website)
Importance of good glucose control – less risks of macrosomia, trauma during birth, hypoglycaemia, IOL
Treatments offered
71
Treatment for GDM if FPG <7 at diagnosis?
Lifestyle advice
• Eat healthy diet, foods with low GI, refer to dietician
• Regular exercise (walking, etc)
Pharmacological
• If failed with diet and lifestyle after 1-2 weeks
• Offer metformin
• Insulin is 2nd line, if metformin CI or not enough
• Glibenclamide is an option
72
Treatment for GDM if FPG >7 at diagnosis?
Pharmacological
• Insulin
• Glibenclamide is an option
73
Antenatal care for GDM? Targets?
o Diabetes and antenatal clinic every 1-2 weeks through pregnancy
o Monitoring using home blood glucose monitor if on insulin (4x daily)
1-hour PPG if on diet or OHA
o Targets:
Fasting – <5.3
1h PPG – <7.8
2h PPG – <6.4
ALWAYS ABOVE 4MMOL/L
o HbA1c
At booking and consider 2nd and 3rd trimester in pre-existing diabetes
o Insulin
Multiple daily injections with glucagon prescribed
74
Labour management of GDM? Timing and glucose management?
o Timing
Birth between 37-38+6 weeks of pregnancy
If complications, elective birth <37 weeks (T1&T2)
Birth no later than 40+6 weeks, offer elective birth
o Glucose monitoring
Every hour during labour (4-7)
Insulin sliding scale infusion may be needed
2-4 hourly after birth and admit if:
• Hypoglycaemia, RDS, signs of cardiac decompensation, neonatal encephalopathy, need fluids/NG feeds
75
Postnatal management of GDM?
o Lifestyle advice
o FPG at 6-12 weeks to exclude diabetes
o Annual HbA1c
76
How common is VTE in pregnancy?
* VTE is a leading cause of maternal morbidity and mortality in developed countries
* 10x more common in pregnancy
* DVT 3x more common than PE
* Most common in post-natal period
77
What does VTE include?
• Thromboembolic events include venous thrombosis (DVT) of the leg, calf or pelvis and pulmonary embolism (PE).
• Thomboembolic disease can occur at any point in the pregnancy:
- Antenatal DVT is more common than postpartum DVT
- VTE is higher in puerperium.
78
Risk factors of VTE - pregnancy?
- Venous stasis in the lower limbs
- Possible trauma to the pelvic veins at the time of delivery
- Changes in the coagulation system:
↑ in procoagulant factors (factors X, VII and fibrinogen)
↓ in endogenous anticoagulant activity
Suppression of fibrinolysis
Significant ↓ in protein S activity.
79
Risk factors of VTE - high risk?
o Hx of >1 VTE, unprovoked or oestrogen-related VTE, single provoked VTE + thrombophilia or FHx, antithrombin 3 deficiency
80
Risk factors of VTE - intermediate risk?
o Thrombophilia but no VTE, single provoked VTE, medical comorbidities (cancer, inflammatory conditions, significant cardiac or respiratory conditions, SLE, sickle cell, nephrotic syndrome), IVDU, antenatal surgery
81
Other risk factors for VTE?
o Age>35, BMI>30, parity 3 or more, smoker, large varicose veins, current infection, pre-eclampsia, immobility, dehydration, multiple pregnancy, ART
82
Symptoms and signs of VTE?
* Clinical signs may be absent.
* DVT
* PE
* Cerebral vein thrombosis (rare)
* If VTE is suspected, treatment should be commenced while diagnostic tests are awaited.
83
Screening performed for VTE?
• Women with previous VTE should be screened for thrombophilia before pregnancy
84
If DVT/PE suspected, what investigations should be performed?
FBC, U&E, LFT, clotting
| ABG, ECG and CXR in PE
85
DVT imaging for diagnosis in pregnancy?
Compression or Duplex US
• If positive – DVT confirmed
• If high clinical suspicion but tests negative – LMWH and repeat imaging in 1 week
• If negative - ruled out and stop LMWH
86
PE imaging for diagnosis in pregnancy?
CXR immediately, if normal:
• V/Q Scan
If abnormal CXR - CTPA
87
Management if VTE suspected or at risk? When given? What are the criteria?
o LMWH (given 6 months and 6 weeks postpartum) - Enoxaparin SC
• Diagnosis of DVT/PE - BDS
• All high risk for VTE prophylaxis
• Any woman undergoing emergency LSCS need 7 days postpartum LMWH
• Antithrombin III deficiency = merits higher doses of LMWH
o Avoid immobility and dehydration
o Elevate legs and compression stockings
88
Management of massive PE in pregnancy?
o Seek expert help
o Airway - assess and optimise if needed
o Breathing - assess - 15L/m NRM O2, ABG
o Circulation - assess - 2 WB cannula in ACF, Blood (FBC, CRP, coagulation), Fluids 0.9% NaCl 500ml bolus
o Ix - CXR, VQ scan
o Rx - LMWH (Carried on until 6 weeks post-partum), alteplase (only if mother moribund)
o Embolectomy in tertiary centres
89
Management of VTE during labour?
o Stop LMWH, keep hydrated
o Planned elective IOL or CS- regional anaesthesia only acceptable >12h since prophylactic dose and >24 after therapeutic dose of LMWH
90
Postnatal care of VTE?
```
o LMWH (can switch to warfarin following pregnancy)
o During next pregnancy, needs VTE prophylaxis throughout and 6 weeks postpartum
```
91
VTE management of antiphospholipid syndrome?
o Aspirin 75mg daily and LMWH from 6 weeks onwards
92
VTE management of antithrombin 3 deficiency?
o LMWH (enoxaparin)
93
Risk factors which score 4 in VTE risk asssessment?
Previous VTE
| OHSS
94
Risk factors which score 3 in VTE risk asssessment?
Previous provoked VTE
Co-morbidity (Cancer, HF, SLE, SCD, IBD)
Surgical procedure
Hyperemesis
95
Risk factors which score 2 in VTE risk asssessment?
C-section in labour
| BMI >40
96
Risk factors which score 1 in VTE risk asssessment?
Thrombophilia
Dehydration
Parity 3 or more
Smoking
Age >35
Multiple pregnancy
FHx of VTE in 1st degree relative
Immobility
BMI >30
Varicose Veins
IVF/ART
Pre-eclampsia
97
Score indications for giving VTE prophylaxis and when?
If 4 or more antenatally - first trimester LMWH
If 3 antenatally - from 28 weeks LMWH
If 2 or more postnatally - LMWH for 10 days
If admitted - consider LMWH
All given antenatally and 6 weeks postnatal
98
Indications for aspirin in pregnancy?
12 weeks
1 high RF
2 or more moderate RF
99
Name high RF for aspirin in pregnancy?
```
Hx of PET
Diabetes
Chronic HTN
Renal disease
Multiple pregnancy
SLE/APS
```
100
Name moderate RF for aspirin in pregnancy?
Nulliparity
BMI >30
FHx of PET
>35 years old
101
Presciption of aspirin if indicated?
At 12 weeks, 75mg
