Jordan University of Science and Technology, Irbid, Jordan
1 To whom correspondence should be addressed at: P.O.B 1572, Amman 11953, Jordan. E-mail: zoamarin{at}hotmail.com
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Abstract |
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Key words: bilateral/IVF/OHSS/oophorectomy/partial
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Introduction |
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The characteristic features of severe OHSS are ovarian enlargement and massive ascites or pleural effusion in conjunction with prominent dyspnoea, haemodynamic instability (tachycardia >120/min and or systolic blood pressure <80 mmHg), oliguria, peripheral oedema, liver dysfunction, adult respiratory distress syndrome, acute renal failure, or thromboembolic phenomena (Golan et al., 1989; Pride et al., 1990
; Navot et al., 1992
; Abramov et al., 1999
).
The pathogenesis of OHSS is thought to be an acute change in vascular permeability (Schenker, 1993). A key role has been attributed to arteriolar vasodilation (Balasch et al., 1998
) and several ovarian factors, such as the ovarian cytokines, prostaglandins, histamine, serotonin, the vascular endothelial growth factor, the renin-angiotensin and the kallikrein-kinin systems (Elchalal and Schenker, 1997
; Rizk et al., 1997
; Kobayashi et al., 1998
; Morris and Paulson, 1999
).
The clinical management of the severe forms of OHSS is based on relatively small series of sporadic case reports, as a small number of cases are seen in a single unit. The syndrome lacks reliable predictive criteria, it also lacks consensus on strategy due to the imperfect understanding of the pathogenesis. Effective measures remain controversial.
We report two cases of severe OHSS who underwent bilateral partial oophorectomy on the grounds of a deteriorating clinical picture after a protracted course of poor response to conservative management.
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Patient 1 |
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After 3 days two embryos of good quality were transferred. Luteal phase support was provided using progestogen vaginal pessaries 400 mg/day (Cyclogest 400; Aventis Pharma, Kent, UK), commencing on the day of embryo replacement.
On post oocyte retrieval day 6, the patient required hospitalization because of nausea, headache, abdominal distension and colic, dyspnoea, fainting and decreasing urinary output. Examination confirmed that there had been a significant increase in both her weight (from 74 to 78 kg) and abdominal girth measurement (from 99 to 106 cm). Ultrasound assessment revealed a right ovary of 13.5 x 13.0 x 12.5 cm and left ovary of 13.2 x 12.8 x 10.5 cm with a moderate amount of fluid in the upper abdomen, and around the liver and spleen. Fundoscopy revealed no papilloedema. Serum investigations revealed haemoconcentration (haematocrit of 47%), low albumin concentrations (24 g/l), low total protein of 57 g/l. Coagulation studies, lupus anticoagulant, anticardiolipin antibody, protein C, protein S, and antithrombin III were within normal limits with a negative allele for factor V Leiden mutation. Based on clinical symptoms and the ultrasound and laboratory findings, her OHSS was categorized as severe (Golan et al., 1989; Navot et al., 1992
).
Management consisted of analgesics, antiemetics and i.v. colloid solutions and an infusion of 20% human albumin solution (3 x 50 ml over 12 h) on a daily basis with careful clinical and laboratory monitoring. Prophylactic treatment with low molecular weight heparin (20 mg s.c. once daily) was started in conjunction with elasticated stockings.
On post oocyte retrieval day 9, the ascites had substantially increased and X-ray examination of the chest showed slightly elevated right diaphragmatic leaflet with left linear atelectatic band and no pleural effusion. Laboratory testing revealed normal concentrations of haemoglobin and packed cell volume but low albumin level of 22 g/l. In view of the marked ascites and the presence of respiratory distress, paracentesis was performed by a transvaginal ultrasonographic approach using the same set-up as for transvaginal oocyte retrieval under intravenous sedation. A total of 2 l of ascitic fluid were removed and a drain was left in situ for another 2 days. This was followed by rapid reaccumulation of the ascites while medically maintaining normal haematocrit, platelets, creatinine, blood urea nitrogen and liver function tests. The serum hCG was 92 IU/l. A second paracentesis was required on day 2 following the removal of the vaginal drain because of severe discomfort and pain. Another 2 l of ascitic fluid were removed and another drain was placed for the next 3 days on continuous drainage.
Sixteen days post oocyte retrieval, and despite early recognition of OHSS and prompt and vigilant attention to fluid management, daily albumin replacement, thrombosis prevention and drainage of ascitic fluid, the ovaries did not show any signs of diminishing in size. The albumin levels were constantly low (Figure 1) and the degree of ascitic fluid production remained high. It was decided to perform laparotomy and bilateral partial oophorectomy. Pregnancy termination was not an option.
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Patient 2 |
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Four days following oocyte retrieval the patient complained of nausea, dyspnoea, abdominal distension and pain. Physical examination revealed stable vital signs, clear lung fields and a distended abdomen. Transvaginal ultrasound demonstrated a right ovary of 13.5 x 13.0 x 12.5 cm and left ovary of 13.5 x 12.5 x 11.5 cm with a small amount of free peritoneal fluid. The patients thrombophilic diathesis indices were all within normal limits. The only alteration in laboratory evaluation was a low serum albumin level of 23 g/l. The patient was admitted for observation, albumin replacement, fluid balance monitoring and prophylactic anticoagulants.
On post oocyte retrieval day 6, the patient underwent transvaginal ultrasound-guided aspiration of 2500 ml of peritoneal fluid and was subsequently transferred to the intensive care unit because of the development of prominent dyspnoea, haemodynamic instability (tachycardia and low blood pressure) and oliguria (urine output <400 ml/24 h), haemoconcentration (45%) and oedema. The drain was removed after 48 h. On post oocyte retrieval day 9, she was noted to have more pronounced dyspnoea, anxiety, tachycardia, blood pressure of 80/50 mmHg with persistent low urinary output. On physical examination she had a relapse of abdominal distension and bilateral decrease in breath sounds. Repeat paracentesis with continuous drainage was performed. Over the ensuing 3 days, the patient became lethargic with complete loss of appetite and continued to complain of shortness of breath and decreased urinary output. Arterial blood gases at ambient conditions, including PO2, PCO2, pH, base deficit, and bicarbonate concentrations were marginally abnormal (pO2 78 mmHg, PCO2 28 mmHg, pH 7.46, base deficit 4.5, HCO3 18.5 mEq/l). Serum albumin levels were persistently low (Figure 1) despite daily infusion of the maximal dose of 150 ml of 20% albumin and close monitoring of fluid balance.
On day 14 post oocyte collection and in view of this protracted course of OHSS and severe anxiety associated with invasive monitoring and multiple medical therapies in the intensive care unit, deteriorating respiratory status, oliguria and haemodynamic instability, it was decided to perform laparotomy and bilateral partial oophorectomy. At operation both ovaries were grossly enlarged to 12 x 12 x 11 cm each. Wedge resection reaching the stromal centre of each ovary was performed on the opposite side to the tubes. The excised wedge consisted of 30% of each ovarian cortex extending to the centre of each ovary, thus excising
30% of each ovary. Any remaining cysts were punctured and drained. The resulting gap was closed in a similar fashion to that for the first patient.
Post-operatively, the patient made a remarkable recovery. There was a marked improvement in serum albumin levels (Figure 1) and urinary output. There was also a very dramatic decrease in the amount of ascitic fluid drainage, coming to a virtual halt within 24 hours. This was combined with weight loss and reversal of abdominal girth. She was able to go home on post-operative day 3 in a very good physical and mental state.
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Discussion |
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The second concern facing physicians is the management of the severe forms of OHSS. The clinical acumen is supported by, and based on, relatively small series of sporadic case reports. In a review of severe OHSS (Abramov et al., 1999), the main signs and symptoms recorded in 209 patients were ascites (99%), dyspnoea (92%), haemoconcentration (95%) and gastrointestinal disturbances (54%). Oliguria was reported in 62 patients (30%), whereas massive pleural effusion appeared in 19%. Peripheral oedema occurred in 13% and thromboembolism in 2%.
Some unusual reported complications include benign intracranial hypertension (Lesny et al., 1999), spontaneous OHSS and deep vein thrombosis (Todros et al., 1999
), OHSS complicated by peritonitis due to perforated appendicitis (Fujimoto et al., 2002
), recurrent cholestasis (Midgley et al., 1999
), hepatic dysfunction (Elter et al., 2001
), internal jugular vein thrombosis (Belaen et al., 2001
), cortical vein thrombosis misinterpreted as intracranial haemorrhage (Tang et al., 2000
), subclavian deep vein thrombosis (Loret de Mola et al., 2000
), myocardial infarction (Ludwig et al., 1999
), superior vena cava thrombosis (Lamon et al., 2000
), pericardial and pleural effusions complicated by supraventricular arrhythmia (Sovova et al., 1999
), deep cerebrovascular thrombosis (Aboulghar et al., 1998
), perforated duodenal ulcer (Uhler et al., 2001
), massive pulmonary oedema, pleural effusion and death (Cluroe and Synek, 1995
; Semba et al., 2000
). These case reports illustrate that OHSS can be a serious and life-threatening complication of controlled ovarian stimulation.
The pathogenesis of OHSS may be explained by an increase in vascular permeability leading to leakage of protein rich intravascular fluid into the peritoneal, pleural and pericardial cavities and a consequent reduction in circulating fluid volume. A number of vasoactive mediators that alter the permeability of capillaries have been identified in serum, follicular fluid and in cultured human luteinizing granulosa cells (Elchalal and Schenker, 1997; Rizk et al., 1997
; Balasch et al., 1998
; Doldi et al., 1999
; Morris and Paulson, 1999
). The severity of the syndrome is directly related to the extent of ovarian response to stimulation. The biochemical link between the ovary and OHSS remain unclear. Transvaginal ultrasound guided aspiration of the multiple corpora lutea as a therapeutical approach to severe OHSS has been reported (Fakih and Bello, 1992
). The authors suggest that bilateral partial oophorectomy was effective not only due to the emptying of the contents of the corpora lutea, but also to the total excision of some luteal cysts where the walls closely incorporate most of the granulosa cells that are the likeliest origin of most vasoactive mediators. This procedure gives some insight into the possible aetiology of OHSS and suggests that the main, or perhaps the sole producer of vasoactive substances in OHSS is the ovary. Although transvaginal ultrasound guided aspiration of the multiple corpora lutea as a therapeutical approach to severe OHSS may seem less aggressive compared with laparotomy, it is the authors opinion that it is less effective as the contents do re-accumulate and is difficult as most of the content of the corpora lutea constitutes a thick coagulum; especially in the later forms of OHSS, which is not very amenable to aspiration. This was observed in the above two cases, both at the ultrasound evaluation of the ovaries and during the surgical interventions.
Although the pathophysiology of OHSS remains unclear, the appearance of its features and symptoms are always associated with the presence of hCG. Therefore, pregnancy may aggravate early OHSS and may induce late OHSS. In the case of the first multiparous patient described, the option of partial oophorectomy was by far the preferred one as opposed to terminating the pregnancy, having in mind that she did not have any plans for future pregnancies. Even if she had such plans, her ovarian reserve, arguably, would have been adequate. In cases of successful assisted reproductive technology outcome, it is the authors view that this procedure is preferable to pregnancy termination.
In the second case described, the patient developed critical OHSS despite the avoidance of pregnancy and lack of further luteal exposure to hCG. Close vigilance for potential OHSS, as well as for the variable appearance of its possible sequelae, was imperative in providing care to this otherwise young and healthy woman. Coasting, hCG dose reduction and cryopreservation of all resulting embryos were three OHSS prevention modalities that were adopted in the case of this patient with no success. The natural course of OHSS is eventually to improve over time, and the marked worsening in status prompted an aggressive search for secondary complications and ways to avoid them, hence the decision to perform bilateral partial oophorectomy. Treatment resulted in complete resolution of symptoms within 3 days.
The procedure of bilateral partial oophorectomy in severe OHSS may seem aggressive as it aims to excise a given volume of the ovaries. There is a plethora of commonly practised procedures that similarly aim at reducing the functional volume of ovaries, albeit for other indications and under different circumstances. Examples are bipolar electrocoagulation (Merchant, 1996), argon laser ovarian capsule drilling and vaporization (Heylen et al., 1994
), laparoscopic ovarian resection (Campo et al., 1993
) for the treatment of PCOS per se, and laparoscopic ovarian electrocautery to prevent the cancellation of IVF cycles due to risk of OHSS in women with polycystic ovaries (Rimington et al., 1997
). The long-term anatomical and physiological sequelae are perhaps similar in all those procedures. Alteration of the tubo-ovarian relationship may be expected in some cases. While this may not make a difference to some patients, such as those requiring IVF and ICSI, it would probably affect the fecundity of others. Research into the long-term ovarian reserve implications of procedures that diminish the overall ovarian mass is needed.
To our knowledge, this is the first report on the use of partial oophorectomy in the management of severe OHSS. The seriousness of this worrying clinical condition and the lack of any definitive therapy to date justify considering new approaches. Although clear scientific evidence is lacking to justify ovarian surgery in OHSS, dramatic changes as evidenced by serial estimations of serum albumin, urinary output, ascitic fluid drainage, daily weight and abdominal girth measurements before and after surgery strengthen the argument that it was the ovarian surgery that was therapeutic and that recovery was not just part of the natural disease process. It has been found that those indirect but reliable indices seem to correlate well with reversal of OHSS (Whelan III and Vlahos, 2000).
The authors propose that this seemingly aggressive procedure is a potentially useful treatment when faced with severely or critically affected patients with OHSS. Further research is needed to provide guidelines for its judicial implementation.
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References |
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