Introduction

Ectopic pregnancy is a gynaecological emergency that often requires urgent treatment. Ectopic pregnancy occurs when the developing blastocyst becomes implanted at a site other than the endometrium of the uterine cavity. The most common extrauterine location is the fallopian tube, which accounts for 91-95 percent of all ectopic pregnancies. Although rare, other locations can include ovarian pregnancy, cervical pregnancy, interstitial pregnancy, hysterectomy/caesarean scar pregnancy, abdominal pregnancy and heterotopic pregnancy. 

Ectopic pregnancy is a notable cause of maternal morbidity and mortality, with haemorrhage resulting from ectopic pregnancy being responsible for up to 15 percent of all pregnancy related deaths and most significantly, 80 percent of deaths within the first trimester. This potentially life-threatening condition requires urgent medical or surgical treatment to reduce the risk of rupture and subsequent major haemorrhage. Early identification, sufficient pre-hospital care and transfer to an appropriate facility is affiliated with good outcomes that see minimal impact on future fertility and pregnancy rates. 

Epidemiology

The rate of ectopic pregnancy is around 1-2 percent with a maternal mortality of 0.2 per 1000 estimated ectopic pregnancies. The mortality ratio is 6.8 times higher in the non-Caucasian population and women over 35 are 3.5 times more likely to experience an ectopic pregnancy than women under 25. The majority of deaths can be attributed to sub-standard care, with the most vulnerable population being women who do not have access to sufficient medical assistance. 

Aetiology and risk factors 

The disruption of normal tubal anatomy is the major cause of ectopic pregnancy and can be caused by congenital anomalies, tumours, previous surgery and infection. The highest risk factors include previous ectopic pregnancy and prior history of tubal surgery.

Women using contraception are at a very low risk of pregnancy, however if they do conceive, the probability of an ectopic pregnancy is high. Approximately 50 percent of diagnosed ectopic pregnancies are not associated with any known risk factors. Women with ectopic pregnancy are also commonly unaware of pregnancy. 

Signs Symptoms

• The basic triad of symptoms include:
  • Abdominal pain (in 80-90% of women)
  • Vaginal bleeding (75%)
  • Amenorrhoea.
• Abdominal pain may radiate to the neck or shoulder 
• Common non-specific symptoms include vomiting, diarrhoea and syncopal or pre-syncopal episodes. 
• Signs can often mimic gastroenteritis
• Episodes of syncope in early pregnancy 
• Lower abdominal tenderness or palpable mass
• Tachycardia / pallor / hypotension / shock / syncope / orthostatic hypotension

Clinical manifestations generally occur 6-8 weeks after the last normal menstrual period. 

In a retrospective study of 2026 pregnant women who presented to the emergency department with first-trimester vaginal bleeding and abdominal pain, 18 percent were diagnosed with ectopic pregnancy. 

Assessment 

History taking is an integral aspect of the formation of a possible ectopic pregnancy diagnosis. 

Important information can include:

• History of presenting complaint
• Past medical and surgical history including obstetric and gynaecology 
• Sexual history including use of contraception
• Recent menstrual periods
• Duration, amount, colour, consistency and pattern of vaginal blood loss
• Pain assessment

Assessment should include 

• Primary and secondary survey 
• Evaluate for haemodynamic instability
• Assess for tenderness, guarding and rigidity by gentle palpation of the abdomen
• ECG 
• Ask the patient if there is any PV bleeding or discharge

Paramedics should consider a differential diagnosis of ectopic pregnancy in all women of reproductive age who are presenting with abdominal pain and have a high suspicion when pain is accompanied by vaginal bleeding. Mismanaging the care of women with ectopic pregnancies is easier than making the correct diagnosis, partly because cases present infrequently, but mainly due to presentations not always being classical. 

Treatment

• Allow the patient to gain a position of comfort 
• Vital signs and ECG.
• Monitor haemodynamic stability
• Gain large bore IV access
• Fluid therapy as per medication protocol with emphasis on permissive hypotension
• Consider analgesia
• Support and reassurance. The patient is likely to suspect a miscarriage and should therefore be cared for in a sensitive manor and provided with the emotional support and the necessary amount of information you can provide at the time, keeping in mind a confirmed diagnosis of ectopic pregnancy cannot be made by the Paramedic and therefore should not be conveyed to the patient. 
• Liaise with obstetrics unit in the metropolitan area or local hospital in country areas, recording all advice in EPCR. 
• Consider CSPSOC advice 

Hospital management and prognosis 

Diagnostic tests include serial Human chorionic gonadotropin (hCG) measurements and transvaginal ultrasound. Both medical and surgical management options exist and depend on the duration of pregnancy and haemodynamic status of the woman.

Conservative medical management is the goal for unruptured ectopic pregnancy and involves methotrexate therapy which comes with a high (above 90%) success rate and is found to have no adverse effects on ovarian function or future pregnancies. Only 35 percent of ectopic pregnancies suit the criteria for medical management. 

Surgical management is necessary for hemodynamically unstable patients, patients with confirmed or impending rupture, patients with co-existing intrauterine pregnancy and patients who do not meet medical criteria. A laparoscopic approach is used and a salpingostomy is performed to remove the fallopian tube (in fallopian tube pregnancy). Prognosis is similar to the medically managed group. The rate of recurrent ectopic pregnancy is 15 percent, rising to 30 percent after two ectopic pregnancies.

Summary 

• The most common extrauterine location for implantation of the developing blastocyst is the fallopian tube
• Haemorrhage from ectopic pregnancy is responsible for 80 percent of first trimester deaths
• Paramedics should consider ectopic pregnancy in all women of reproductive age who are presenting with abdominal pain
• Clinical manifestations generally occur 6-8 weeks after last normal menstrual period
• History taking forms a large part of a suggested pre-hospital diagnosis
• Identifying risk factors is important, however 50 percent of women have no known risk factors at diagnosis
• If contraceptive failure occurs, risk of ectopic pregnancy is high
• Rupture can result in hypovolaemic shock 
• Early identification and transfer to appropriate care is associated with good outcomes

References

Curtis, K., & Ramsden, C. (2016). Emergency and trauma care for nurses and paramedics (2nd ed.). Chatswood, NSW: Elsevier Australia

Barnhar, K. T. (2018). Ectopic pregnancy. BMJ Best Practice. Advance online publication. https://bestpractice-bmj-com.ipacez.nd.edu.au/topics/en- gb/174/pdf/174/Ectopic%20pregnancy.pdf

Ectopic pregnancy and miscarriage: Diagnosis and initial management in early pregnancy of ectopic pregnancy and miscarriage. (2012). National Institute for Health and Clinical Excellence. Retrieved May 17, 2020, from https://ranzcog.edu.au/RANZCOG_SITE/media/RANZCOG- MEDIA/Women%27s%20Health/Statement%20and%20guidelines/Clinical%20- %20Gynaecology/NICE-Ectopic-pregnancy-and-miscarriage.pdf?ext=.pdf

Government of Western Australia North Metropolitan Health Service- Women and Newborn Health Service, 2020. Pregnancy: First Trimester Complications. Obstetrics and Gynaecology Directorate. Retrieved from https://www.kemh.health.wa.gov.au/~/media/Files/Hospitals/WNHS/For%20health% 20professionals/Clinical%20guidelines/OG/WNHS.OG.PregnancyFirstTrimester.pdf

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Tulandi, T. (2020). Ectopic pregnancy: Epidemiology, risk factors, and anatomic sites. Topic 5481 (29), UpToDate. Retrieved May 17, 2020, from https://www-uptodate- com.ipacez.nd.edu.au/contents/ectopic-pregnancy-epidemiology-risk-factors-and- anatomic- sites?search=ectopic%20pregnancy&source=search_result&selectedTitle=3~150&usa ge_type=default&display_rank=3

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