Not to be confused with [[Meigs's syndrome]]. Certainly not to be confused with [[Pre-eclampsia]] > [!references]- > - [Dunn - Ovarian hyperstimulation syndrome](x-devonthink-item://1B980E68-9725-4F49-B661-794DCF02C90D) > - [Hayes’ - Ovarian Hyperstimulation Syndrome](x-devonthink-item://44A99CA3-7503-4917-9EBE-D42F3675DAEF) > - [RANZCOG Consensus Statement on Ovarian Hyperstimulation Syndrome (2015)](bookends://sonnysoftware.com/ref/DL/15472) - [online](https://www.anzsrei.com/pdf/prevention-ovarian-hyperstimulation-syndrome-kwik.pdf) > - [ A modern classification of OHSS (2009)](bookends://sonnysoftware.com/ref/DL/244229) > - [Modified Golan classification of OHSS](https://radiopaedia.org/articles/modified-golan-classification-of-ovarian-hyperstimulation-syndrome) > - [RWH presentation on OHSS admissions and severity](https://ranzcogasm.com.au/wp-content/uploads/2023/03/presentation.pptx-63.pdf) > - Case: [Critical OHSS presenting with isolated unilateral massive pleural effusion](https://ranzcogasm.com.au/wp-content/uploads/2023/03/presentation.pptx-82.pdf) ## Overview - Iatrogenic complication of fertility treatments to induce final oocyte maturation and trigger oocyte release, often in women undergoing in vitro fertilisation - Occurs following an exaggerated response to stimulation of ovaries by FSH when LH or hCG is also present - typically a self-limited condition lasting 10-14 days with supportive treatment usually sufficient, but can persist if pregnancy occurs, and can be severe and life-threatening in some cases ### Pathogenesis - ↑ capillary permeability (likely from ↑ VEGF) → leakage of fluid into extravascular spaces → hypovolaemia and haemoconcentration, ↓ albumin → oedema, ascites, pleural effusions; rarely pericardial effusion, shock, renal failure, [[DVT]], [[ARDS]] - Condition is generally characterised by **ovarian enlargement** and **↑ vascular permeability** ### Risk factors > ~5% following ovulation induction with exogenous gonadotrophins. severe OHSS in 0.2% - 1% of stimulation cycles. - younger patients - weight <60kg - PCOS - previous OHSS - rapidly rising estradiol levels - pregnancy increases risk, severity, and duration due to hCG - [[Hypothyroidism|hypothyroid]] - formation of a large number of intermediate sized (10-14mm) follicles ## Severity > - There are [several](bookends://sonnysoftware.com/ref/DL/244229) different scores for OHSS; bizarrely, the 2009 ANZCOG consensus statement actually doesn't provide one, noting that there is no universally agreed classification of the severity of OHSS (even though one would think that a specialist committee producing a consensus statement would have the capacity to produce a consensus opinion about how to assess the condition they are providing a consensus about). > - Any of the above can give a general sense of the issues to consider when discussing the case with gynaecology ; getting the grade right is less important than having a general sense of the difference between mild and more severe versions of the disease - haematocrit >45% generally considered a marker of moderate or severe OHSS - serum albumin is not a criterion for severity of OHSS and has uncertain predictive value - generally higher estradiol >10,000 - 20,000 for moderate, >20k for severe ### Dunn (very simple classification for FACEMs) - mild - abdominal discomfort - moderate - USS detected ascites - severe - *clinical* ascites and pleural effusion - haemoconcentration - critical - hypovolaemic shock - renal & resp failure - severe haemoconcentration ### Golan criteria 1989 | Category | Description | | ------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Mild OHSS<br> | ***Grade 1:***<br>Abdominal distension and discomfort<br><br>***Grade 2:***<br>*Features of gr1 +* nausea, vomiting, +/- diarrhoea. Ovaries enlarged to 5-12 cm | | Moderate OHSS | ***Grade 3:***<br>Features of mild OHSS + *ultrasound evidence of ascites* | | Severe OHSS | ***Grade 4:***<br>Features of mod OHSS + *clinical* evidence of ascites +/- hydrothorax or breathing difficulties<br><br>***Grade 5:***<br>All of the above + Δ in blood volume, ↑ blood viscosity due to third-spacing, [[Coagulopathy]], AKI | ### Navot criteria 1992 | | Severe | Critical | | ------------ | ----------------------------- | ------------------------------------------------ | | Ovary | variably enlarged | variably enlarged | | ascites | tense ascites +/- hydrothorax | ascites +/- hydrothorax +/- pericardial effusion | | haematocrit | > 45% | >55% | | WBC | >15,000 | >25,000 | | urine output | oliguria | oliguria or anuria | | renal f(x) | - Cr 88 - 132<br>- CrCl ≥ 50 | - Cr ≥ 141<br>- CrCl < 50 | | Liver | dysfuction | dysfunciton | | oedema | anasarca (severe oedema) | anasarca | | Other | | - thromboembolic phenomena<br>- [[ARDS]] | ### Rizk & Aboulghar (1999) | Category | Description | | -------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Moderate | Discomfort, pain, nausea, distension, ultrasonic evidence of ascites and enlarged ovaries, normal haematological and biological profiles | | Severe | ***Grade A:***<br>Dyspnea, oliguria, nausea, vomiting, diarrhoea, abdominal pain, clinical evidence of ascites, marked distension of abdomen or hydrothorax, ultrasound showing large ovaries and marked ascites, normal biochemical profile<br><br>***Grade B:***<br>Grade A plus massive tension ascites, markedly enlarged ovaries, severe dyspnea and marked oliguria, increased haematocrit, elevated serum creatinine and liver dysfunction<br><br>***Grade C:***<br>Complications such as respiratory distress syndrome, renal shut-down or venous thrombosis | ## Complications - hypotension due to third-spacing fluid losses - dehydration and electrolyte imbalance due to vomiting - renal failure - ARDS - [[ovarian torsion]] - sepsis - thromboembolic disease - infection (chest, urine) ## Investigations - EUC looking for [[hyponatremia]], [[hyperkalemia|hyper-K]] - FBC looking for haemoconcentration (eg haematocrit >45%) - LFT looking for mild-mod transaminitis - CRP - coags - +/- estradiol - POCUS abdomen looking for ascites - POCUS ECHO exclude pericardial effusion - CXR looking for pleural effusion ## Diagnosis - history of ovarian stimulation - typical clinical features - nausea, vomiting - diarrhoea - transvaginal ultrasound - Examination - fluid retention - oedema - ascites - pleural effusion ## Management - most cases resolve spontaneously - onset 3-7 days post stimulation usually less severe than delayed onset - less severe forms resolve in 7 days in absence of pregnancy vs 10-20 days in severe forms - supportive treatment of - hypovolaemia - pain - nausea - bloating (eg possible paracentesis for symptoms relief -- may not alter course of disease) - dyspnoea - strict fluid balance - monitor electrolytes - DVT ppx - analgesia -- may need PCA opiates ## Disposition - discuss all cases with gyanecology -- at minimum needs close follow up - admit moderate and above cases to hospital - HDU/ICU admit for pts with resp compromise, shock, organ failure