2016 5 OHSS Flashcards
** What are the reporting responsibilities in relation to OHSS? **
- Licensed centres need to report severe & critical cases to HFEA
- Verbally within 12 working hours, form within 24
- Gynae units need to inform fertility centre
** What information should women be provided about OHSS? **
- Verbal & written
- To all women undergoing fertility treatment
- Including 24-hour contact number
** Which women with OHSS can be managed as outpatients? **
- Mild & moderate
- Severe in select cases
** What outpatient management is suitable for OHSS? **
- Fluid intake & output monitoring
- Avoid NSAIDs
- LWMH for all severe, some moderate
- Paracentesis can be done
- Review every 2-3 days unless signs of worsening
- Bloods if signs of worsening, particularly haematocrit as sign of intravascular volume depletion
** In what situations should women with OHSS be admitted? **
- Unable to achieve satisfactory pain control
- Unable to maintain adequate fluid intake
- Signs of worsening
- Unable to attend OP F/U
- Critical OHSS
** How should fluid balance be managed in OHSS? **
- Oral, guided by thirst as 1st line
- IV fluids 2nd line
- If persistent haemoconcentration despite colloid volume replacement, consider invasive monitoring
- Avoid diuretics unless oliguria once fluid replete & ascites drained
** What are the indications for paracentesis in OHSS? **
- Severe abdo distension & pain
- SOB & resp compromise
- Oliguria despite adequate volume replacement
** How should paracentesis be carried out in OHSS? **
- Under US guidance
- Abdominally or vaginally
** What additional signs & symptoms should prompt investigation for thromboembolism in OHSS? **
Unusual neurology inc headache, visual disturbance, dizziness, neck pain
Esp as tends upwards & to arterial system
Even if several weeks after OHSS improved
** What are the increased risks for pregnancy following OHSS? **
- Pre-eclampsia
- Preterm delivery
** When is surgical management indicated in OHSS? **
Coincident problem eg
1. Adnexal torsion
2. Ovarian rupture
3. Ectopic pregnancy
How does OHSS develop?
- Excessive ovarian response
- Proinflammatory mediators: VEGF & cytokines
- Increased vascular permeability
- Loss of fluid into 3rd space as ascites, pleural & pericardial effusions
- Hypovolaemia with paradoxical hypo-osmoloality & hyponatraemia
- Prothrombotic effect
What is the incidence of OHSS?
Mild: 1/3
Moderate or severe: 1-8%
Hospitalisation: 0.3%
What are the risk factors for OHSS?
- Previous Hx OHSS
- PCOS
- Increased antral follicle count
- High levels AMH
- GnRH agonists rather than antagonists to stimulate
What is the history needed to assess OHSS?
- Timing of trigger & onset
- Medication used as trigger
- Number of follicles on scan
- Number of embryos collected
- If/how many embryos replaced
- PCOS diagnosis
What are the symptoms of OHSS?
- Abdominal bloating
- Abdominal pain
- N&V
- SOB, inability to lie flat
- Reduced urine output
- Leg swelling
- Vulval swelling
- Comorbidities eg thrombosis
What examination is needed for OHSS?
- General: dehydration, oedema, HR, BP, RR, weight
- Abdominal: ascites, palpable mass, peritonism, girth
- Respiratory: pleural effusion, pneumonia, pulmonary oedema
What investigations are needed for OHSS & findings expected?
- FBC, haematocrit rise
- CRP, rise in severity
- U&E, hypoNa+ & hyperK+
- Serum osmolality, hypo
- LFTs, rise enzymes, drop albumin
- Clotting, rise fibrinogen, drop antithrombin
- hCG
- USS: ovarian size, pelvic & abdo free fluid, Doppler if torsion suspected
What additional tests may be indicated in OHSS?
- ABG
- D-dimers
- ECG
- CXR
- CTPA or V/Q
When is OHSS expected to present?
Early: within 7 days of injection
Late: 10+ days after injection, usually due to endogenous hCG from early pregnancy, usually more severe
What symptoms would not be expected in OHSS?
- Severe pain
- Pyrexia
- Peritonism
What are the differential diagnoses for OHSS?
- Pelvic infection
- Pelvic abscess
- Appendicitis
- Ovarian torsion
- Cyst rupture
- Bowel perforation
- Ectopic pregnancy
What are the features of mild OHSS?
- Abdominal bloating
- Mild abdominal pain
- Ovarian size < 8cm3
What are the features of moderate OHSS?
- Moderate abdominal pain
- N&V
- US evidence of ascites
- Ovarian size 8-12cm3
