BARTON CLARKE
4. Sand PK, Bowen LW, Ostergard DR. Uninhibited urethral relaxation: An unusual cause of incontinence. Obstet Gynecol 1986; 68: 645-648. 5. Kulseng-Hanssen S. Prevalence and pattern of unstable urethral pressure in one hundred and seventy four gynecological patients referred for urodynamic investigation. Am J Obstet Gynecol 1983; 146: 895-900. 6. Cardozo LD, Versi E. Urethral instability in normal postmenopausal patients. Proc 15th Annual Meeting ICS London 1985; 115-116. 7. Tapp AJS, Cardozo LD, Versi E, Studd JWW. The prevalence of variation of resting urethral pressure in women and its association with lower urinary tract function. Brit J Urol 1988; 61: 314-317. 8. Versi E. Relevance of urethral pressure profilometry to date. In: Drife JO, Hilton P, Stanton S. Micturition, 1st Edition, London, Springer Verlag, 1989; 6: 81-97. 9. Blaivas JG, Labib KL, Bauer SB, Retck AB. A new approach to electromyography of the external urethral sphincter. J Urol 1977; 117: 773-717.
275
10. Scott RJ, Ostergard DR. Urethral syndrome. In: Ostergard DR, Bent AE. Urogynecology and Urodynamics Theory and Practice, 3rd Edition. Baltimore, Williams and Wilkins 1991; 2 4 264. 11. Jarvis GL. The management of urinary incontinence due to primary vesical sensory urgency by bladder drill. Brit J Uroll982; 54: 374-376. 12. Kulseng-Hanssen S. Pudendal block in female patients with unstable urethral pressure. Proc 14th Annual Meeting ICS 1984. Innsbruck 118-120. 13. Hindmarsh JR, Gosling PT, Deane AM. Bladder instability. Is the primary defect in the urethra? Brit J Urol 1983; 55: 648-651. 14. Bergman A, Koonings PP, Ballard CA. Detrusor instability. Is the bladder the cause or effect? Neurourol Urodynam 1988; 7: 186. 15. Barbalias GA, Meares EM. Female urethral syndrome, clinical and urodynamic perspectives. Urology 1984; 2: 208-212. 16. Lose G, Jorgensen L. Effect of urethral catheterization on urethral sphincter EMG and pressure profile. Neurourol Urodynam 1989; 8: 473-480.
Aust NZ J Obstet Cynaecol 1992; 32: 3: 275
Eisenmenger Syndrome in Pregnancy R. Jeyamalar*, MD, V. Sivanesaratnam, MD and P. Kuppuvelumani, MD "Departments of Medicine and Obstetrics and Gynaecology, Faculty of Medicine, University of Malaya, Kuala Lumpur Eisenmenger syndrome in pregnancy carries a high maternal and fetal morbidity and mortality, especially in the postpartum period (1). This is due to increased right to left shunting that results in tissue hypoxaemia and metabolic acidosis although the reasons for this worsening shunt are unclear. We describe our experiences with 3 patients, 2 of whom were treated in the conventional manner and succumbed, and 1 who survived the pregnancy and an exsanguinating postpartum haemorrhage by timely surgical intervention and the careful use of pharmacological agents that decreased the amount of right to left shunting and helped maintain an adequate arterial oxygenation.
CASE REPORTS Case I K, gravida 2 para 1, presented at 27 weeks' gestation with progressive effort dyspnoea. Her first pregnancy 2 years previously had been uneventful. On examinaAddress for correspondence: Dr R. Jeyamalar, Department of Medicine, Faculty of Medicine, University of Malaya, 59100 Kuala Lumpur, Malaysia
tion, she had clubbing of her fingers and toes and central cyanosis. There was clinical evidence of right ventricular hypertrophy and pulmonary hypertension. AbdominaI examination revealed a gravid uterus whose size corresponded with gestational age. The electrocardiogram (ECG) and the chest X-ray were consistent with the Eisenmenger syndrome. A 2-dimensional echocardiogram demonstrated a large atrial septa1 defect with pulmonary hypertension. While breathing room air, the arterial oxygen tension and saturation were 10 kPa and 92% and with oxygen at Wminute by nasal prongs, there was improvement to 17 kPa and 99% respectively. The patient was admitted and given oxygen for episodes of dyspnoea. At 38 weeks, she went into spontaneous labour. A healthy male infant, birth-weight 2,400 g, was delivered by low forceps under epidural analgesia. Throughout labour haemodynamics remained stable; the arterial oxygen tension and saturation were 8 kPa and 90-92% respectively with oxygen at 3l/minute via nasal prongs. Within 24 hours of delivery however, the patient had increasing right to left shunting with worsening cyanosis and acidosis. Despite increasing oxygen therapy she continued to deteriorate and succumbed on the third postdelivery day.
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Table 1. Case 3 Flow Chart of Patient’s Progress Postpartum Time ~ 0 2 SO2 Management chart Day (kPa) (Yo) post delivery ~
1
2
3
4 5
6
7
8 9
10 26
0600 1200 1800 0600 1000 1400 1800 0600 1200 1800 1600 2200 01 15 0200 0600 1200 1800 0600 1200 1800 2040 0040 0130 0600 1300 1400 2200 0600 1800 0400 0600 2000 0800
13.1 10.8 9.9 9.2 9.4 13.3 17.1 13.7 8.1 8.0 8.1 7.4 4.9 7.6 13.9 8.1 7.9 8.5 6.4 6.3 5.8 5.2 4.9 8.0 4.7 4.4 5.3 6.2 6.9 5.5
3.6 3.4 4.7 6.8
97 95 95 94 96 98 98 97 92 92 93 89 74 92 98 92 91 93 86 85 81 78 12 72 71 71 78 85 89 81 54 46 38 88
0 2 at 8L/minute nasal prongs 0 2 at 8L/minute nasal prongs 0 2 at 8L/minute nasal prongs 0 2 at lOL/minute face mask Aramine infusion started
Aramine dose reduced Aramine stopped
Febrile. Aramine restarted Aramine stopped Heparin stopped
Heparin restarted Aramine restarted Aramine dose increased Aramine stopped Diltiazem started
Profuse vaginal bleeding Still bleeding Postoperation Breathing room air
p 0 2 =arterial oxygen tension; SO2 = arterial oxygen saturation
Case 2
TAL, gravida 1 para 0, was seen at 38 weeks’ gestation with dyspnoea. Soon after admission, she went into spontaneous labour and delivered a healthy male infant. On the third postdelivery day, her condition deteriorated and she was transfered to this hospital. At admission, she was febrile and central cyanosis and clubbing of the toes were noted. Cardiovascular examination revealed features consisent with Eisenmenger syndrome. A tender uterus was palpable per abdomen and on vaginal examination, the 0s was patulous and remnants of placental tissue were felt. While breathing oxygen at Wminute via face mask, the arterial oxygen tension and saturation were only 3.4 kPa and 51% respectively. The patient was started on antibiotics and the uterus evacuated. Over the next few days, the infection settled but she developed worsening hypoxia and succumbed. Case 3
SK, gravida 1 para 0, was admitted at 28 weeks’ gestation with haemoptysis. She had previously been diagnosed as having a ventricular septa1 defect with
systemic pulmonary artery pressures. On examination, she had digital clubbing and central cyanosis. She had clinical evidence of right ventricular hypertrophy and pulmonary hypertension. Abdominal examination revealed a single fetus corresponding to dates. While breathing room air, the arterial oxygen tension was 6.5 kPa and saturation was 88% and with oxygen at 6 I/minute by nasal prongs, these values improved to 9.2 kPa and 94% respectively. The patient was given oxygen at 5-8 l/minute throughout the pregnancy. Low dose aspirin (150 mg daily) and intravenous heparin were started maintaining the partial thromboplastin time at 2 to 2% times the control. The pregnancy progressed normally and at 38 weeks, the patient went into spontaneous labour. A healthy male infant weighing 2,500 kg was delivered with assisted low forceps. An hour following delivery heparin was recommenced. Within 24 hours, there was evidence of increasing right to left shunting with accompanying hypoxaemia and metabolic acidosis (table 1). Despite increasing oxygen therapy, arterial oxygenation did not improve appreciably and an aramine infusion was then started at 6.6 ug/minute. This resulted in systemic vasoconstriction and reversal of right to left shunting with an increase in oxygen tension from 9 kPa to 13 kPa over the next 4 hours. Unfortunately at this dose, the peripheral vasoconstricton became too severe resulting in metabolic acidosis and the aramine was therefore discontinued. During this period, large volumes of fluids (3-4 I/day) were given to maintain the central venous pressure (CVP) at about 5-8 mmHg to ensure an adequate right ventricular output. On the fourth postpartum day, she developed a fever of 39°C and the arterial oxygen tension dropped to 4.8 kPa. Aramine was recommenced and within an hour, the arterial oxygen tension improved to 7.6 kPa. Due to vaginal bleeding, heparin was stopped on Day 5. The bleeding ceased but within 24 hours, blood gases began to deteriorate and reinstitution of heparin and aramine did not result in sustained improvement in oxygen saturation. Diltiazem was then introduced at an oral dose of 60 mg 3 times a day. This appeared to reduce the amount of right to left shunting and stabilized the oxygen saturation in the range 85-90%. On day 9, the patient had massive vaginal bleeding despite correction of her coagulation profile and high dose oxytocin infusion. Total abdominal hysterectomy was performed following the failure of ligation of both internal iliac arteries and ovarian vessels medial to the ovaries to stop the uterine bleeding. A total of 24 pints of blood was transfused over 24 hours. Following surgery, the arterial oxygen tension and saturation were only 3.4 kPa and 46.4%. Subsequent to the reintroduction of the heparin and diltiazem these indices slowly improved. The patient was finally discharged on Day 26 with aspirin 150 mg daily and diltiazem 60 mg thrice a day. A month later, she was back to her predelivery status of health.
R. JEYAMALAR ET AL
DISCUSSION In Eisenmenger syndrome, death results from an inbalance between the pulmonary and systemic circulations. The degree of right to left shunting that occurs is dependent on the ratio of systemic to pulmonary vascular resistances. In the postpartum period, the high pulmonary vascular resistance and the normal or low systemic resistance favour increased right to left shunting and worsening cyanosis. By carefully balancing the shunt in favour of less right to left shunting and increased pulmonary blood flow, we successfully managed our last patient. The use of pulse oximetry during labour and for a week postpartum will help detect early changes in the shunt so that the appropriate therapy could be instituted early (figure 1). increasing PVR Hypoxia Acidosis Pulmonary vascular resistance (PVR)
t
1
Oxygen aspirin calcium antagonists decreasing PVR
Shunt
t 1
increasing SVR sympathomimetic agents systemic vascular resistance (SVR) infection acidosis hypovolaemia decreasing SVR
Figure 1. Factors affecting the pulmonary and systemic vascular resistances. Both systems should be kept in balance with a favourable tilt towards increased pulmonary blood flow.
Antenatally, increasing the inspired oxygen concentration resulted in an improvement in the arterial oxygen tension indicating that in patients 1 and 3, the pulmonary vasculature was capable of vasodilating to some extent resulting in a fall in pulmonary vascular resistance and shunting. Spinnato et a1 have suggested that the presence of a fixed pulmonary hypertension that is not responsive to oxygen therapy carries a grave prognosis and may be an absolute indication to terminate the pregnancy (2). Labour was uncomplicated in all patients and neither epidural analgesia nor oxytocin resulted in significant changes in haemodynamics or shunt flow. Postdelivery the increase in right to left shunting and the accompanying metabolic acidosis that occurred could not be reversed by further increasing the inspired
277
oxygen content, unlike the experience of others (2). We therefore had to resort to an alpha sympathomimetic agent (aramine) to increase systemic vascular resistance and shift the shunt towards increased pulmonary blood flow. This had this desired effect although it gave rise to side effects necessitating its stoppage. Calcium antagonists are known to decrease pulmonary artery pressures in the Eisenmenger syndrome (3) and oral diltiazem appeared to have shifted the ratio of pulmonary vascular resistance to systemic vascular resistance in a favourable manner resulting in a decrease in right to left shunting. The role of anticoagulation in Eisenmenger syndrome is controversial. Naeye and coworkers (4) postulated that the rapid increase in pulmonary vascular resistance postpartum, is due to widespread pulmonary thrombosis although at autopsy the main pulmonary arteries are usually free of clots. Gleisher (1) strongly advocated the use of heparin from the 20th week of gestation, but others have felt otherwise (5). In Naeye’s necropsy findings however, there was fresh thrombotic material within the small channels of the plexiform lesions consisting of platelet aggregates (4) and we therefore advocate the use of low dose aspirin in the pregnant patient with Eisenmenger syndrome. A pregnant patient with Eisenmenger syndrome should be advised to have her pregnancy terminated. If this cannot be done, we advocate the use of low dose aspirin. Delivery is preferably by the vaginal route (1). Pulse oximetry should be used throughout labour and during the first week postpartum to detect early evidence of worsening shunt. The arterial oxygen saturation should be maintained at 85-90% and the pulmonary and systemic resistances carefully balanced with appropriate pharmacotherapy to achieve this. Heparin may be beneficial but contributed significantly to our patient’s bleeding.
References 1. Gleisher N, Midwall J, Hochberger D, Jaffin H. Eisenmenger’s Syndrome in pregnancy. Obstet Gynae Survey 1979; 34: 721-741. 2. Suinnato JA. Kravnach BJ. Coooer MW. Eisenmenger’s Svndrome i n pregnancy: Epidural anaesthesia for elective caesareansection. NEJM 1981; 304: 1215-1217. 3. Wong CK. Lau CP. Leung WH, Cheng CH. The use of nifedipine in patients with Eisenmenger’s Syndrome complicating patency of the arterial duct. Int J Cardiol 1989; 25: 173-178. 4. Naeye RL, Hagstrom JWC, Talmadge BA. Post partum death with maternal congenital heart disease. Circulation 1967; 36: 304-312. 5. Pitts JA, Crosby WM, Basta LL. Eisenmenger’s Syndrome in Pregnancy. A Heart J 1977; 93: 321-326.
4. Sand PK, Bowen LW, Ostergard DR. Uninhibited urethral relaxation: An unusual cause of incontinence. Obstet Gynecol 1986; 68: 645-648. 5. Kulseng-Hanssen S. Prevalence and pattern of unstable urethral pressure in one hundred and seventy four gynecological patients referred for urodynamic investigation. Am J Obstet Gynecol 1983; 146: 895-900. 6. Cardozo LD, Versi E. Urethral instability in normal postmenopausal patients. Proc 15th Annual Meeting ICS London 1985; 115-116. 7. Tapp AJS, Cardozo LD, Versi E, Studd JWW. The prevalence of variation of resting urethral pressure in women and its association with lower urinary tract function. Brit J Urol 1988; 61: 314-317. 8. Versi E. Relevance of urethral pressure profilometry to date. In: Drife JO, Hilton P, Stanton S. Micturition, 1st Edition, London, Springer Verlag, 1989; 6: 81-97. 9. Blaivas JG, Labib KL, Bauer SB, Retck AB. A new approach to electromyography of the external urethral sphincter. J Urol 1977; 117: 773-717.
275
10. Scott RJ, Ostergard DR. Urethral syndrome. In: Ostergard DR, Bent AE. Urogynecology and Urodynamics Theory and Practice, 3rd Edition. Baltimore, Williams and Wilkins 1991; 2 4 264. 11. Jarvis GL. The management of urinary incontinence due to primary vesical sensory urgency by bladder drill. Brit J Uroll982; 54: 374-376. 12. Kulseng-Hanssen S. Pudendal block in female patients with unstable urethral pressure. Proc 14th Annual Meeting ICS 1984. Innsbruck 118-120. 13. Hindmarsh JR, Gosling PT, Deane AM. Bladder instability. Is the primary defect in the urethra? Brit J Urol 1983; 55: 648-651. 14. Bergman A, Koonings PP, Ballard CA. Detrusor instability. Is the bladder the cause or effect? Neurourol Urodynam 1988; 7: 186. 15. Barbalias GA, Meares EM. Female urethral syndrome, clinical and urodynamic perspectives. Urology 1984; 2: 208-212. 16. Lose G, Jorgensen L. Effect of urethral catheterization on urethral sphincter EMG and pressure profile. Neurourol Urodynam 1989; 8: 473-480.
Aust NZ J Obstet Cynaecol 1992; 32: 3: 275
Eisenmenger Syndrome in Pregnancy R. Jeyamalar*, MD, V. Sivanesaratnam, MD and P. Kuppuvelumani, MD "Departments of Medicine and Obstetrics and Gynaecology, Faculty of Medicine, University of Malaya, Kuala Lumpur Eisenmenger syndrome in pregnancy carries a high maternal and fetal morbidity and mortality, especially in the postpartum period (1). This is due to increased right to left shunting that results in tissue hypoxaemia and metabolic acidosis although the reasons for this worsening shunt are unclear. We describe our experiences with 3 patients, 2 of whom were treated in the conventional manner and succumbed, and 1 who survived the pregnancy and an exsanguinating postpartum haemorrhage by timely surgical intervention and the careful use of pharmacological agents that decreased the amount of right to left shunting and helped maintain an adequate arterial oxygenation.
CASE REPORTS Case I K, gravida 2 para 1, presented at 27 weeks' gestation with progressive effort dyspnoea. Her first pregnancy 2 years previously had been uneventful. On examinaAddress for correspondence: Dr R. Jeyamalar, Department of Medicine, Faculty of Medicine, University of Malaya, 59100 Kuala Lumpur, Malaysia
tion, she had clubbing of her fingers and toes and central cyanosis. There was clinical evidence of right ventricular hypertrophy and pulmonary hypertension. AbdominaI examination revealed a gravid uterus whose size corresponded with gestational age. The electrocardiogram (ECG) and the chest X-ray were consistent with the Eisenmenger syndrome. A 2-dimensional echocardiogram demonstrated a large atrial septa1 defect with pulmonary hypertension. While breathing room air, the arterial oxygen tension and saturation were 10 kPa and 92% and with oxygen at Wminute by nasal prongs, there was improvement to 17 kPa and 99% respectively. The patient was admitted and given oxygen for episodes of dyspnoea. At 38 weeks, she went into spontaneous labour. A healthy male infant, birth-weight 2,400 g, was delivered by low forceps under epidural analgesia. Throughout labour haemodynamics remained stable; the arterial oxygen tension and saturation were 8 kPa and 90-92% respectively with oxygen at 3l/minute via nasal prongs. Within 24 hours of delivery however, the patient had increasing right to left shunting with worsening cyanosis and acidosis. Despite increasing oxygen therapy she continued to deteriorate and succumbed on the third postdelivery day.
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Table 1. Case 3 Flow Chart of Patient’s Progress Postpartum Time ~ 0 2 SO2 Management chart Day (kPa) (Yo) post delivery ~
1
2
3
4 5
6
7
8 9
10 26
0600 1200 1800 0600 1000 1400 1800 0600 1200 1800 1600 2200 01 15 0200 0600 1200 1800 0600 1200 1800 2040 0040 0130 0600 1300 1400 2200 0600 1800 0400 0600 2000 0800
13.1 10.8 9.9 9.2 9.4 13.3 17.1 13.7 8.1 8.0 8.1 7.4 4.9 7.6 13.9 8.1 7.9 8.5 6.4 6.3 5.8 5.2 4.9 8.0 4.7 4.4 5.3 6.2 6.9 5.5
3.6 3.4 4.7 6.8
97 95 95 94 96 98 98 97 92 92 93 89 74 92 98 92 91 93 86 85 81 78 12 72 71 71 78 85 89 81 54 46 38 88
0 2 at 8L/minute nasal prongs 0 2 at 8L/minute nasal prongs 0 2 at 8L/minute nasal prongs 0 2 at lOL/minute face mask Aramine infusion started
Aramine dose reduced Aramine stopped
Febrile. Aramine restarted Aramine stopped Heparin stopped
Heparin restarted Aramine restarted Aramine dose increased Aramine stopped Diltiazem started
Profuse vaginal bleeding Still bleeding Postoperation Breathing room air
p 0 2 =arterial oxygen tension; SO2 = arterial oxygen saturation
Case 2
TAL, gravida 1 para 0, was seen at 38 weeks’ gestation with dyspnoea. Soon after admission, she went into spontaneous labour and delivered a healthy male infant. On the third postdelivery day, her condition deteriorated and she was transfered to this hospital. At admission, she was febrile and central cyanosis and clubbing of the toes were noted. Cardiovascular examination revealed features consisent with Eisenmenger syndrome. A tender uterus was palpable per abdomen and on vaginal examination, the 0s was patulous and remnants of placental tissue were felt. While breathing oxygen at Wminute via face mask, the arterial oxygen tension and saturation were only 3.4 kPa and 51% respectively. The patient was started on antibiotics and the uterus evacuated. Over the next few days, the infection settled but she developed worsening hypoxia and succumbed. Case 3
SK, gravida 1 para 0, was admitted at 28 weeks’ gestation with haemoptysis. She had previously been diagnosed as having a ventricular septa1 defect with
systemic pulmonary artery pressures. On examination, she had digital clubbing and central cyanosis. She had clinical evidence of right ventricular hypertrophy and pulmonary hypertension. Abdominal examination revealed a single fetus corresponding to dates. While breathing room air, the arterial oxygen tension was 6.5 kPa and saturation was 88% and with oxygen at 6 I/minute by nasal prongs, these values improved to 9.2 kPa and 94% respectively. The patient was given oxygen at 5-8 l/minute throughout the pregnancy. Low dose aspirin (150 mg daily) and intravenous heparin were started maintaining the partial thromboplastin time at 2 to 2% times the control. The pregnancy progressed normally and at 38 weeks, the patient went into spontaneous labour. A healthy male infant weighing 2,500 kg was delivered with assisted low forceps. An hour following delivery heparin was recommenced. Within 24 hours, there was evidence of increasing right to left shunting with accompanying hypoxaemia and metabolic acidosis (table 1). Despite increasing oxygen therapy, arterial oxygenation did not improve appreciably and an aramine infusion was then started at 6.6 ug/minute. This resulted in systemic vasoconstriction and reversal of right to left shunting with an increase in oxygen tension from 9 kPa to 13 kPa over the next 4 hours. Unfortunately at this dose, the peripheral vasoconstricton became too severe resulting in metabolic acidosis and the aramine was therefore discontinued. During this period, large volumes of fluids (3-4 I/day) were given to maintain the central venous pressure (CVP) at about 5-8 mmHg to ensure an adequate right ventricular output. On the fourth postpartum day, she developed a fever of 39°C and the arterial oxygen tension dropped to 4.8 kPa. Aramine was recommenced and within an hour, the arterial oxygen tension improved to 7.6 kPa. Due to vaginal bleeding, heparin was stopped on Day 5. The bleeding ceased but within 24 hours, blood gases began to deteriorate and reinstitution of heparin and aramine did not result in sustained improvement in oxygen saturation. Diltiazem was then introduced at an oral dose of 60 mg 3 times a day. This appeared to reduce the amount of right to left shunting and stabilized the oxygen saturation in the range 85-90%. On day 9, the patient had massive vaginal bleeding despite correction of her coagulation profile and high dose oxytocin infusion. Total abdominal hysterectomy was performed following the failure of ligation of both internal iliac arteries and ovarian vessels medial to the ovaries to stop the uterine bleeding. A total of 24 pints of blood was transfused over 24 hours. Following surgery, the arterial oxygen tension and saturation were only 3.4 kPa and 46.4%. Subsequent to the reintroduction of the heparin and diltiazem these indices slowly improved. The patient was finally discharged on Day 26 with aspirin 150 mg daily and diltiazem 60 mg thrice a day. A month later, she was back to her predelivery status of health.
R. JEYAMALAR ET AL
DISCUSSION In Eisenmenger syndrome, death results from an inbalance between the pulmonary and systemic circulations. The degree of right to left shunting that occurs is dependent on the ratio of systemic to pulmonary vascular resistances. In the postpartum period, the high pulmonary vascular resistance and the normal or low systemic resistance favour increased right to left shunting and worsening cyanosis. By carefully balancing the shunt in favour of less right to left shunting and increased pulmonary blood flow, we successfully managed our last patient. The use of pulse oximetry during labour and for a week postpartum will help detect early changes in the shunt so that the appropriate therapy could be instituted early (figure 1). increasing PVR Hypoxia Acidosis Pulmonary vascular resistance (PVR)
t
1
Oxygen aspirin calcium antagonists decreasing PVR
Shunt
t 1
increasing SVR sympathomimetic agents systemic vascular resistance (SVR) infection acidosis hypovolaemia decreasing SVR
Figure 1. Factors affecting the pulmonary and systemic vascular resistances. Both systems should be kept in balance with a favourable tilt towards increased pulmonary blood flow.
Antenatally, increasing the inspired oxygen concentration resulted in an improvement in the arterial oxygen tension indicating that in patients 1 and 3, the pulmonary vasculature was capable of vasodilating to some extent resulting in a fall in pulmonary vascular resistance and shunting. Spinnato et a1 have suggested that the presence of a fixed pulmonary hypertension that is not responsive to oxygen therapy carries a grave prognosis and may be an absolute indication to terminate the pregnancy (2). Labour was uncomplicated in all patients and neither epidural analgesia nor oxytocin resulted in significant changes in haemodynamics or shunt flow. Postdelivery the increase in right to left shunting and the accompanying metabolic acidosis that occurred could not be reversed by further increasing the inspired
277
oxygen content, unlike the experience of others (2). We therefore had to resort to an alpha sympathomimetic agent (aramine) to increase systemic vascular resistance and shift the shunt towards increased pulmonary blood flow. This had this desired effect although it gave rise to side effects necessitating its stoppage. Calcium antagonists are known to decrease pulmonary artery pressures in the Eisenmenger syndrome (3) and oral diltiazem appeared to have shifted the ratio of pulmonary vascular resistance to systemic vascular resistance in a favourable manner resulting in a decrease in right to left shunting. The role of anticoagulation in Eisenmenger syndrome is controversial. Naeye and coworkers (4) postulated that the rapid increase in pulmonary vascular resistance postpartum, is due to widespread pulmonary thrombosis although at autopsy the main pulmonary arteries are usually free of clots. Gleisher (1) strongly advocated the use of heparin from the 20th week of gestation, but others have felt otherwise (5). In Naeye’s necropsy findings however, there was fresh thrombotic material within the small channels of the plexiform lesions consisting of platelet aggregates (4) and we therefore advocate the use of low dose aspirin in the pregnant patient with Eisenmenger syndrome. A pregnant patient with Eisenmenger syndrome should be advised to have her pregnancy terminated. If this cannot be done, we advocate the use of low dose aspirin. Delivery is preferably by the vaginal route (1). Pulse oximetry should be used throughout labour and during the first week postpartum to detect early evidence of worsening shunt. The arterial oxygen saturation should be maintained at 85-90% and the pulmonary and systemic resistances carefully balanced with appropriate pharmacotherapy to achieve this. Heparin may be beneficial but contributed significantly to our patient’s bleeding.
References 1. Gleisher N, Midwall J, Hochberger D, Jaffin H. Eisenmenger’s Syndrome in pregnancy. Obstet Gynae Survey 1979; 34: 721-741. 2. Suinnato JA. Kravnach BJ. Coooer MW. Eisenmenger’s Svndrome i n pregnancy: Epidural anaesthesia for elective caesareansection. NEJM 1981; 304: 1215-1217. 3. Wong CK. Lau CP. Leung WH, Cheng CH. The use of nifedipine in patients with Eisenmenger’s Syndrome complicating patency of the arterial duct. Int J Cardiol 1989; 25: 173-178. 4. Naeye RL, Hagstrom JWC, Talmadge BA. Post partum death with maternal congenital heart disease. Circulation 1967; 36: 304-312. 5. Pitts JA, Crosby WM, Basta LL. Eisenmenger’s Syndrome in Pregnancy. A Heart J 1977; 93: 321-326.
