Abdominal Pain in Females of Childbearing Years

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Squad 54 has been dispatched to Curtis Hall for a complaint of abdominal pain. As the crew arrives on scene, they are directed to a 19-year-old female lying in bed, clutching her abdomen and complaining of pain. As Michael, the EMT crew chief, begins his assessment, he notes that she is able to talk, indicating that both her airway and breathing are adequate. Her skin is pink and her extremities are warm and dry, indicating that for the moment she has adequate circulation. Michael asks her what is wrong, and she says she is having pain in her lower stomach.

Before continuing this scenario, let’s consider abdominal pain in the childbearing-age female.

Epidemiology

Abdominal pain is an extremely common complaint in the emergency setting, accounting for up to 10% of all emergency department visits.¹ Although abdominal pain frequently occurs, it can be a frustrating chief complaint, as it is a rather non-specific problem that may not even directly represent the disease process actually affecting the patient. Because of their more complex anatomy, females of reproductive age require special consideration when they present with abdominal discomfort. A survey of women of reproductive age reported that 39% of this group experience non-menstrual pelvic pain yearly, which may manifest as abdominal pain.² Every year in the United States, 5.8% of every 1,000 women presenting to an ED receive a diagnosis of pelvic inflammatory disease, and 1.1% of 1,000 women are diagnosed with an ectopic pregnancy.³ These are both serious conditions carrying significant morbidity. Ectopic pregnancies also have a significant mortality.

Anatomy

The abdominal cavity is the largest internal cavity in the body (Table 1). Its complexity lies not only within its many structures, but also with its interaction of the nerves that innervate them. There are three distinct pathways in the abdomen that transmit pain: visceral, somatic and referred. Nociceptors sense and transmit pain sensation, which is described as either visceral or somatic. Visceral is pain sensed from the actual internal organs and their autonomic innervation that may be the earliest manifestation of pain. This pain is often a response to stretching or inflammation and is responsible for referred pain due to many organ nerve plexi and pathways crossing. Somatic pain receptors lie within both the skin and internal tissues and are able to pick up sensations related to temperature, swelling and vibration. Somatic pain is usually more focalized and may present as sharp pain, where visceral pain, sometimes called peritoneal pain, is more generalized, dull and achy. Referred pain, on the other hand, occurs away from the injured organ and is a result of the brain's inability to determine where the pain in a particular area is coming from. While the absolute reason for referred pain is uncertain and debated, it is thought to be a function of how the nerves develop in the fetal period along with crossed connections as they synapse.

There are several organs in the lower abdominal quadrants, including the cecum, appendix, sections of the ascending colon, ureter and kidney on the right, and the sigmoid colon, sections of the descending colon, ureter and kidney on the left. The bladder lies midline. In the female patient, the ovaries and fallopian tubes are found bilaterally in the lower quadrants. The uterus is midline just posterior to the bladder. While it can be easily argued that the pelvis and abdomen are two distinct body regions, in the emergency setting they can be thought of as one, as pain in these quadrants presents in a similar manner.

EMTs are trained to ask questions to characterize the situation in which the illness or pain presented, as well as to see how it has evolved. These questions, which follow the OPQRST mnemonic, address onset, provocation, quality, if the pain radiates, severity of the pain, as well as describing the time of onset and duration. Additionally, there are some specific questions that can be asked of a woman experiencing abdominal pain to help further guide management and to narrow the etiology of the pain. While it is not a first responder’s job to come up with the diagnosis, many times it is helpful to think of a list of common possibilities that could be causing this pain. This list is known as a “differential diagnosis.” The differential diagnosis of abdominal pain should prioritize the diagnoses that are most common, as well as those likely to have a high morbidity or mortality. The questions asked of the patient should be aimed at trying to narrow down the EMT's differential list.

One rule of thumb for any woman of childbearing age is to assume she is pregnant until proven otherwise. It doesn’t matter if she had her menstrual cycle yesterday or six months ago, assume she is pregnant as you perform an assessment. Keeping this in mind, one must take a systematic approach to developing diagnoses.

To develop a differential diagnosis, it is essential to have both a history of present illness and an accurate physical exam. Obtaining a history includes an accurate description of pain using the OPQRST mnemonic, as well as determining the patient’s history of any abdominal problems and any specific symptoms previously experienced.

There are several ways to perform an abdominal assessment. One option is the quadrant method, where the abdomen is broken down into four quadrants (upper right, upper left, lower right, lower left); however, a system-based approach can be a better assessment.

Since pain does not always present in a specific area, limiting an assessment to one abdominal quadrant can make a differential diagnosis difficult. However, if you can approach the patient’s assessment one organ system at a time, it is less likely that something will be missed. Work from the head down, going system by system, developing a wide differential. Start wide and narrow it down based on presentation. Table 2 identifies body systems based on a list of conditions that may cause abdominal pain.

This broad list of differentials can be narrowed down based on the presentation of each particular case. For example, the absence of fever can eliminate many causes, such as infections, while presence of bruising may support others. Keeping in mind that the management of most abdominal pain in the field will be similar, the following questions can help identify when there might be a more serious cause.

Physical Exam

As with any physical exam, one must develop a systemic manner in which it is done the same way each time. Although this patient presents with abdominal pain, remember that all abdominal pain does not represent an abdominal problem. For example, inferior myocardial infarction may present with abdominal pain. A full physical exam is always warranted. The first part of the abdominal exam is done without even touching the patient. Ask the patient to expose her abdomen and perform a visual inspection. Look for visual distension, bruising, bleeding or other abnormalities. Auscultate with the stethoscope, listening for bowel sounds, noting both frequency and pitch. Pay particular attention for bruit, which is the noise made by turbulent blood flow as it passes through an obstruction in an artery. If there is no abdominal bruit, palpate the abdomen. Bruits may suggest an abdominal aortic aneurysm and palpation of the area may exacerbate the disease.⁵

Begin palpating the abdominal quadrant diagonally opposite the quadrant where the patient is experiencing pain. It is important to not just palpate the abdomen, but to also look at the patient’s body posture and facial expressions at the same time. If the patient is not able to tolerate light palpation, there is no need to continue eliciting pain by pressing deeper on that quadrant. Look to see if the patient’s abdomen tenses up as soon as touched or if she can tolerate deep palpation before pain becomes intolerable. The inability to tolerate light palpation is a peritoneal sign, which again suggests diffuse irritation to the peritoneal lining of the abdominal cavity and may suggest pathology related to peritonitis, the most common example being appendicitis. Sometimes, peritoneal signs are best elicited when moving the stretcher into the ambulance, as even with the gentlest hands, unavoidable vibrations occur.

Using the original scenario, the following cases will help illustrate different presentations of abdominal pain.

As Michael continues questioning his female patient, she explains that she woke up this morning with nausea and generalized lower abdominal pain. She says she feels feverish and has not wanted to eat anything all day. She began vomiting about a half-hour ago, and the pain has shifted to the right side of her umbilicus. She does not want to move, because any movement or vibration is unbearably painful.

This is a classic presentation for acute appendicitis. While more than 95% of patients with appendicitis have abdominal pain, only about 50% have the other classic symptoms. Appendicitis occurs usually from stool obstructing the outlet of the appendix, lymphoid hyperplasia, or inflammation/obstruction blocking the ongoing production of mucus by the appendix. While definitive treatment is surgical removal of the appendix, emergency management consists of hydration with IV fluids, keeping the patient NPO (nothing by mouth) and comfort measures. The old dogma used to be not to give pain medication in order to have an accurate abdominal exam; however, studies continue to show that pain medication does not interfere with the diagnostic accuracy of abdominal examinations, and it adds to patient comfort.⁶

It is also helpful to keep in mind that one-third of women of childbearing age with appendicitis are misdiagnosed with pelvic inflammatory disease (PID).⁷ In order to differentiate appendicitis from PID, the following three characteristics are 99% sensitive for ruling out appendicitis: 1) no migration of pain, 2) bilateral abdominal tenderness, 3) no nausea or vomiting.⁸ While this does not necessarily rule in PID, it can rule out appendicitis. Clinically, you can look for these things to help point the hospital receiving team in the right direction.

Pelvic inflammatory disease is characterized by an ascending infection of vaginal bacteria into the pelvic cavity, which can manifest in uterine, fallopian or ovarian pain. The most important clinical impact of PID is the damage it causes to the fallopian tubes. If not treated thoroughly and quickly, it can cause scarring and increase the chance of an ectopic pregnancy six- to 10-fold, and increase the risk of chronic pelvic pain four-fold. Proper management of pelvic inflammatory disease includes broad-spectrum antibiotics, because both aerobic and anaerobic bacteria can cause PID. Significant risk factors for PID include younger age of first sexual intercourse, older sex partners, alcohol use before intercourse, concurrent chlamydia infection or prior suicide attempt. High-risk behaviors are generally risk factors for developing PID because of their association with sexually transmitted infections and alteration of the vaginal flora.

Unfortunately, the signs and symptoms of pelvic inflammatory disease are generally non-specific. Non-specific abdominal pain in a female must always be considered for PID because of its impact on female fertility. The CDC suggests minimum criteria for diagnosing and beginning treatment of PID, including lower abdominal tenderness, adnexal tenderness or cervical motion tenderness. Other supporting criteria include oral temperature >38°C, abnormal cervical or vaginal discharge (macropurulent), presence of abundant WBCs on microscopy of vaginal secretions, elevated erythrocyte sedimentation rate, elevated C-reactive protein, or laboratory documentation of cervical infection with N. gonorrhoeae or C. trachomatis.¹⁰

It is important to know about PID in the field because it will be a presenting problem in a number of patients. Remember that diagnosis is not necessary, particularly in new cases; however, be sure to ask about a history of PID, since supportive measures can be performed without a differential diagnosis. These include IV fluids and transport in a position of comfort to a facility that can provide definitive diagnosis and treatment. Pelvic examinations in the field are not indicated, as they only allow for increased discomfort and undue pain and will not affect acute prehospital management. This is not to say a visual exam of the external vagina is unwarranted to ensure there is no gross bleeding that needs to be cared for urgently.

Case #2: One piece of information can change a differential diagnosis.

Continued questioning reveals that your patient got drunk a few months ago and had unprotected intercourse at a party. She hasn’t told anyone or done anything about it because she is so afraid she might be pregnant, she just wants to put it out of her mind and hope it will go away. Her vital signs reveal that she is tachycardic and her blood pressure is 118/76. She is extremely uncomfortable and screams each time you attempt to move her.

This information provides a high index of suspicion for ectopic pregnancy. An ectopic pregnancy is when a fertilized egg does not properly implant in the uterus, but instead implants or grows somewhere outside of the uterus. The most common site of implantation outside the uterus is the fallopian tube, which can rupture if a fetus begins to grow inside the closed tube. Classically, the pain is severe, to the lateral aspects of the pelvis and unilateral. Unfortunately, the presentation is highly variable. When an ectopic pregnancy is suspected, perform a visual inspection of the external aspect of the vagina to check for gross bleeding. An internal pelvic exam is not indicated, as it will not change the prehospital management of this patient. A patient is likely to have positive pregnancy test results because she is, in fact, pregnant, but unfortunately in the wrong location. Vaginal bleeding or spotting can often be confused with having a menstrual period, so a patient may not know she is pregnant. One might question why a normal low blood pressure in this patient is concerning. In a healthy 19-year-old, a blood pressure of 96/56 would be great; however, because this patient is in intense pain and probably anxious, one would expect her blood pressure to be higher. The whole clinical picture is important when assessing a patient. While it’s important to not just treat numbers, her clinical picture suggests she is in compensatory shock, most likely secondary to intravascular blood loss secondary to a ruptured ectopic pregnancy.

This patient warrants rapid transport to an emergency department, IV access and frequent vital signs monitoring. Two IVs are not necessary except in the case of profound hypotension that is not responsive to initial fluid therapy. Reassess the patient regularly, and consider the Trendelenburg position if she becomes hemodynamically unstable. The receiving ED should be informed early of the critical nature of this patient in order to activate necessary personnel. This is a surgical emergency.

Case #3

Changing our patient’s presentation slightly, as Michael enters the dorm room, the patient complains of an intense gnawing pain between her umbilicus and her sternum that she says feels like it is burning through her back. She says she just got back from Mardi Gras in New Orleans this morning and has consumed a great deal of alcohol over the last week or so. She says the pain, which is constant and unrelenting, started this morning and has gotten progressively worse.

The most common causes of acute pancreatitis are gallstones and excessive alcohol consumption.¹¹ Ecchymosis, or bruising, on the flanks (Grey Turner's sign) or around the umbilicus (Cullen's sign) are signs of blood in the abdominal cavity, which suggests pancreatic necrosis and abdominal bleeding. Other diseases or injuries that cause internal bleeding may also mimic these signs, and it is important to note that they typically take 24–48 hours to manifest. Patients with pancreatitis often complain of pain originating inferior to the sternum and radiating posteriorly. The pain is usually constant and gnawing; however, if there is involvement of the gallbladder with gallstones, pain may present in sharp bursts that come and go. Jaundice can be present when the biliary tract is obstructed. These patients’ hemodynamic status should be monitored closely, as a significant amount of fluid can leave the intravascular space, the blood vessels, and go into the tissues or body cavities. Management of this patient should consist of a thorough physical exam, close monitoring of vital signs, IV fluid hydration, keeping her NPO, and emergent transport in a position of comfort to a notified emergency department.

Treatment of Abdominal Pain in the Field and Beyond

As shown in Table 1, there are many different pathologies contributing to abdominal pain. Remember, however, that common things are common, so management should be based on the common etiologies of abdominal pain. Don’t go looking for a zebra when the horse is right in front of you. Luckily, the emergency treatment of most abdominal pain is the same. While we have previously discussed the importance of considering the complex anatomy of females of childbearing age, anatomy doesn’t really change the management greatly on an EMS call. As always, the ABCs come first. Most abdominal pain is vague and may not lead you directly to the pathology, unlike the cases above. It is your responsibility to remember that, even without a serious differential diagnosis, hemodynamic instability may occur at any time and regular reevaluation during transport is important. These patients should receive a thorough physical exam, checking the genital area for gross bleeding. Internal pelvic exams are not performed by EMS providers. Any time a patient presents with signs of hemodynamic instability, including tachycardia, signs of dehydration or falling blood pressure, administer normal saline through at least one IV. The abdominal compartment can hold a lot of fluid, and significant internal bleeding can occur before physical symptoms develop. Keep all patients with abdominal pain NPO, as they might need emergent surgery, and because food releases gastric and pancreatic contents and shunts vital blood flow from other organs to the gut. Monitor vital signs periodically and use the Trendelenburg position if blood pressure dictates; otherwise, place the patient in a position of comfort. IV pain medication can be started to provide patient comfort, but it is best to contact medical control or the receiving facility for recommendations.

Transition of care should convey the emergent status of the patient using pertinent history, trended vital signs and physical exam findings. If there is something you feel the receiving staff should be told, make it known no matter how busy they are. You sometimes have information from the field that is not available to the emergency department.

ED management consists of reevaluation and narrowing down the differential diagnoses. After initial stabilization, a complete history and physical, one of the first tests run will be a pregnancy test, as it can affect the differential diagnosis, as well as which drugs or imaging studies can be done in managing this patient. In the case of pelvic pathology, the OB/GYN on call will normally be activated to do a thorough physical exam and a vaginal ultrasound. CT/MRI or US may be used to further narrow down the diagnosis, along with blood tests to measure pancreatic enzyme activity, liver function, and markers of inflammation and infection. A surgeon or internal medicine staff may be called in for definitive management.

Conclusion

Although abdominal pain in the potentially pregnant female can seem quite complex, once broken down to simple steps, management is quite simple. Remembering the ABCs and using a systematic approach on each patient can help simplify the emergency. You should feel a certain sense of relief that your job is to stabilize and transport to the appropriate facility as quickly and comfortably as possible, leaving some of the more difficult diagnoses to the hospital team. Try to notify the receiving facility as early as possible so they can activate the necessary teams, even if they are not as receptive as you would like. This can make a large difference in ED staff preparedness and improve patient care. With any emergency, EMTs must act as the liaison between patient, family and hospital staff for the most effective management of even the most complex patients.
 

References

1. Bengiamin R, Budhram G, King K, Wightman J. Chapter 21: Abdominal Pain. In: Marx J, ed. MD Consult: Marx: Rosen's Emergency Medicine, Vol 2010. https://www.mdconsult.com.libproxy.tulane.edu:2048/books/page.do?sid=1078388978&eid=4-u1.0-B978-0-323-05472-0..00021-9&isbn=978-0-323-05472-0&type=bookPage§ionEid=4-u1.0-B978-0-323-05472-0..00021-9&uniqId=225263251-3#4-u1.0-B978-0-323-05472-0..00021-9 ed. Mosby, 2009.

2. Chapter 145: Inflammatory and anatomic diseases of the intestine, peritoneum, mesentery and omentum. from Goldman: Cecil Medicine, on MD Consult. https://www.mdconsult.com.libproxy.tulane.edu:2048/das/book/body/225578276-5/1079522335/1492/553.html#4-u1.0-B978-1-4160-2805-5..50150-6--cesec1_6312. Accessed 11/6/2010, 2010.

3. Curtis KM et al. Visits to emergency departments for gynecologic disorders in the United States, 1992–1994. Obstet Gynecol 91:1007, 1998.

4. Colucciello SA, Lukens TW, Morgan DL. Abdominal pain: An evidence-based approach. Emerg Med Pract 1:2, 1999.

5. Core T, Hayes K. Acute abdominal pain: A systematic approach to adult assessment. Nursing Critical Care, 2010. https://journals.lww.com/nursingcriticalcare/Abstract/2008/05000/Acute_abdominal_pain__A_systematic_approach_to.7.aspx. Accessed 11/7/2010, 2010.

6. Thomas SH, Silen W, Cheema F, et al. Effects of morphine analgesia on diagnostic accuracy in emergency department patients with abdominal pain: A prospective, randomized trial. J Am Coll Surg 196(1):18–31, 2003.

7. Dahlberg D, Lee C, Fenion T, Willoughby D. Differential diagnosis of abdominal pain in women of childbearing age: Appendicitis or pelvic inflammatory disease? Adv Nurse Pract 12(1):40, 2004.

8. Morishita K, Gushimiyagi M, Hashiguchi M, et al. Clinical prediction rule to distinguish pelvic inflammatory disease from acute appendicitis in women of childbearing age. Am J Emerg Med 25(2):152–157, 2007.

9. Beigi RH, Wiesenfeld H. Pelvic inflammatory disease: New diagnostic criteria and treatment. Obstet Gynecol Clin North Am 30:777, 2003.

10. Centers for Disease Control and Prevention: 2006 guidelines for treatment of sexually transmitted disease. MMWR 55:11, 2006.

11. Gupta K, Wu B. Acute pancreatitis Ann Intern Med 153(9):ITC51, 2010.

Kevin T. Collopy, BA, FP-C, CCEMT-P, NREMT-P, WEMT, is an educator, e-learning content developer and author of numerous articles and textbook chapters. He is also a flight paramedic for Ministry Spirit Medical Transportation in central Wisconsin and a lead instructor for Wilderness Medical Associates. Contact him at kcollopy@colgatealumni.org.

Sean M. Kivlehan, MD, MPH, NREMT-P is an emergency medicine resident at the University of California San Francisco and a former New York City paramedic for 10 years. Contact him at sean.kivlehan@gmail.com.

Scott R. Snyder, BS, NREMT-P, is the EMS education manager for the San Francisco Paramedic Association in San Francisco, CA, where he is responsible for the original and continuing education of EMTs and paramedics. Scott has worked on numerous publications as an editor, contributing author and author, and enjoys presenting on both clinical and EMS educator topics. Contact him at scottrsnyder@me.com.