OHSS Flashcards
Percentage of OHSS in ART cycles (mild and severe)
33% mild
3.1-8.0% severe
Definition ohss
Systemic disease resulting from vasoactive products released by hyperstimulated ovaries
Pathophysiology ohss
Increased capilllary permeability, leading to leakage of fluid from the vascular compartment, with third-space fluid accumulation and intravascular dehydration
Ovarian enlargement with local and systemic effects of pro inflammatory mediators
Symptoms ohss
Abdominal bloating Abdominal pain Extreme thirst Nausea and vomiting Anuria/oliguria SOB Thrombosis Vulval swelling Leg swelling
Risk factors ohss
Young age
PCOS
DM
Previous OHSS
High follicular phase LH
High-dose gonadotrophin stimulation regimens
Use of fnRH analogues as opposed to antagonists
Multiple follicular response with stimulation
High estradiol levels during treatment (>20000 p/mol)
Exposure to hcg
Conception
Ways to reduce incidence or severity
Low-dose stimulation protocols
Follicular monitoring
GnRH antagonist cycles rather than analogues
Progesterone instead of hcg for luteal suppport
Abandoning cycle prior to hcg admin and oocyte collection
Delaying ET/ freezing
Hcg trigger w/h until estradiol levels have returned to acceptable levels
GnRH agonist triggering final maturation of oocyte (but reduced pregnancy rates)
What drugs to be avoided in OHSS
NSAIDS
When to admit to hospital with OHSS
Pain control Unable to have adequate fluid intake Worsening OHSS despite OP intervention Unable to attend OP f/U Have critical OHSS
Indications for paracentesis
Severe abdominal dissension and abdominal pain secondary to ascites
SOB and rep compromise secondary to ascites
Oliguria despite adequate volume replacement, secondary to increased abdominal pressure causing reduced renal perfusion
What is reduced in OHSS?
Hypovolaemia
Reduced serum similarity
Low sodium
Investigations
FBC U/Es (hyponat, hyperkal) Serum Osmolality (hypo) Pelvic USS Haematocrit CRP LFTs (high and low albumin) Coag (high fibrinogen) Hcg
Other tests
ABG, D-diner, ECG, CXR, CTPA
DDx OHSS
Ectopic Pelvic infection Pelvic abscess Appendicitis Torsion Cyst rupture Bowel perf
Things to ascertain from history
Time of onset of symptoms relative to trigger
Medication used for trigger (hcg or GnRH agonist)
Number of follicles on final monitoring scan
Number of eggs collected
Was there an ET
PCOS
Mild OHSS
Abdominal bloating
Mild abdo pain
Ovarian size usually <8cm
Moderate OHSS
Moderate abdo pain
Nausea and vomiting
USS evidence of ascites
Ovarian size usually 8-12 cm
Severe OHSS
Clinical ascites Oliguria Haematocrit > .45 Hyponatraemia Hypo-osmol Hyperkalaemia Low albumin Ovarian size usually >12cm
Critical OHSS
Tense ascites Haematocrit >0.55 WCC >25 Oliguria/anuria VTE ARDS
Management OHSS
If admitted - monitored daily; OP r/v every 2-3 days
Analgesia and antiemetic
Fluid replacement oral route by thirst
IV Colloids
Paracentesis if severe pain, SOB, or oliguria
LMWH
