Overview of Culdocentesis
Culdocentesis is a medical procedure that was once commonly used to diagnose a condition called hemoperitoneum, which is when blood fills the space within the abdomen. However, with the advent of advanced scanning technology like transvaginal sonography, its use has decreased in developed countries. That is not the case however in countries where such technology may not be readily available, like Papua New Guinea. There, culdocentesis is often used to confirm a ruptured ectopic pregnancy, which is a health crisis and demands immediate surgical action.
This diagnostic method is especially critical in populations where conditions like anemia and pelvic inflammatory disease (PID) are common. PID often has symptoms similar to a ruptured ectopic pregnancy, making it harder to diagnose the pregnancy without a culdocentesis. Needless to say, the procedure has been a gamechanger in treating ectopic pregnancy, especially before sonography became prevalent.
Beyond diagnosing ectopic pregnancies though, culdocentesis can also be valuable in detecting other medical conditions. For example, acute fallopian tube inflammation, known as salpingitis, or PID, would show up as pus-filled fluid. Endometrioma, a type of ovarian cyst, would produce a dark, ‘chocolate’-like fluid during the procedure, while other conditions might lead to the presence of ascitic fluid.
However, it’s important to note that hemoperitoneum could lead to misleading results in a culdocentesis. Other health issues like hemorrhagic ovarian cysts, twisted ovarian cysts or ruptured ovarian follicles can cause this condition. Another crucial point is that a clear or blood-streaked fluid during a culdocentesis does not necessarily discredit the possibility of an ectopic pregnancy. In such a scenario, the procedure might have to be repeated at a later time, as the pregnancy might exist but has not ruptured yet. Around 1 in 4 or 1 in 3 ectopic pregnancies can result in hemoperitoneum, making it a considerable risk for women in their reproductive years.
Anatomy and Physiology of Culdocentesis
In a side view of a woman’s pelvis, the bladder is located at the front, right behind the pubic bone. Just behind the bladder, there is the uterus, which sits on top of the bladder. The uterus and the vagina sit at right angles to each other, and the point where they meet is where the cervix is located.
There is a little pocket-like space behind the uterus, known as the pouch of Douglas. This is separated from the uterus by a wall of tissue called the rectouterine septum. The pouch of Douglas is an area where blood could potentially gather if there is any internal (peritoneal) bleeding. Located behind the pouch of Douglas is the rectum, which is part of the large intestine.
Why do People Need Culdocentesis
A ruptured ectopic pregnancy happens when a fertilized egg grows outside of the womb – most commonly in one of the fallopian tubes – and then bursts. It’s a very serious condition with some clear warning signs. You would need immediate medical attention if you have a ruptured ectopic pregnancy or if there’s a suspicion of it.
Some of the signs and symptoms include a positive pregnancy test or an elevated beta-human chorionic gonadotropin (this is a hormone produced by the cells of the placenta during pregnancy), abdominal pain, vaginal bleeding, feeling rigid or having a sudden strong pain in your abdomen when touched (that’s what’s meant by ‘peritoneal signs’), feeling pressure in the rectal area, and signs of shock like a rapid heartbeat and low blood pressure. The feeling of shock occurs from losing blood rapidly into the abdomen (a condition known as hemoperitoneum). If any of these symptoms are present, immediate medical care would be needed.
When a Person Should Avoid Culdocentesis
There are some circumstances where certain conditions can make specific procedures unadvisable. For instance, if it’s known that a woman has a mass or a womb that tilts backwards towards the spine instead of forwards (termed a “retroverted uterus”) and this fills the area at the back of the womb (known as the “pouch of Douglas”), the procedure may be inappropriate.
Equipment used for Culdocentesis
The equipment needed for this procedure includes a speculum, which is a tool used to widen an opening in your body so the doctor can see or reach an interior part more easily. They will also use lubricated jelly to make the procedure more comfortable for you. A Foerster sponge forceps, also known as ring forceps, is used to hold onto or manipulate delicate tissues. Sterile gauze or sponges will be used to keep the procedure area clean.
An iodine solution is used to cleanse the skin and prevent infection. A tenaculum or a Vulsellum forceps, both types of tools for holding and stabilizing tissues, might be used. An 18-gauge spinal needle, which is 5 cm long, will be used in some part of the procedure. They will also use a 10mL syringe, often referred to as a three-finger control syringe, for administering any necessary medications or solutions during the procedure.
Lidocaine, a type of local anesthetic used to numb the specific area of the body, will be used to minimize any discomfort during the procedure. And lastly, gloves are always used to keep the procedure as sterile and safe as possible.
Who is needed to perform Culdocentesis?
In order to perform the medical procedure, a medical professional is needed, such as a doctor or a nurse practitioner, who is trained and experienced in such procedures. Additionally, support from either a nurse or a nursing aide (nurse’s helper) is required. Their role is to assist the doctor, ensuring everything goes smoothly during the process.
Preparing for Culdocentesis
To get ready for a procedure called culdocentesis, the necessary tools should be set up on a table nearby for the doctor to use. Safe cleanliness practices are crucial when setting up. To assist during this process, a nurse or nursing aide should be in the room. The patient will need to lie down in what’s called a lithotomy position, ideally on a movable bed with supports for the legs. This is to make sure the patient is as comfortable as possible.
How is Culdocentesis performed
The doctor will begin your check-up with a hands-on exam to check your adnexa (the area encompassing the ovaries, fallopian tubes, and supporting tissues) and cervix for any signs of discomfort. They will also check the position of your uterus and look for any masses or tenderness at the back of the lower part of your pelvic cavity, also known as the cul-de-sac.
Next, the doctor will carry out a speculum examination. This involves using a lubricated tool, called a speculum, that is carefully inserted into your vagina, helping the doctor examine the area more thoroughly.
After the speculum is in place, the doctor will use a tool called a Foerster sponge forceps to introduce a special gauze, soaked in iodine, into your body. This is done to cleanse your cervix and the back part of your vagina, known as the posterior fornix.
Then, a tenaculum or Vulsellum forceps is applied to the lower part of the cervix. The doctor will warn you about potential cramps during this part of the procedure. This tool is then moved to expose the back part of your vagina.
The doctor will then numb the mucosa (a layer of skin) about 1 cm below the back part of the cervix with lidocaine, an anesthetic.
The doctor will then use a long needle filled with a small amount of air or sterile saline and insert it 1 cm below where the cervix ends in the posterior fornix, pushing the needle in further by 3 to 4 cm and then injecting the air or saline. If it’s difficult to inject the air or saline, the doctor will reposition the needle until it’s easier. The needle should enter the Pouch of Douglas, which is a slight dip in the pelvic cavity behind the uterus. The doctor may aim the needle towards the sacrum (the lower part of your spine) and away from the uterus to help with positioning.
Finally, the doctor will try to draw out fluid with a syringe. If three attempts yield no fluid, the procedure should be stopped.
Possible Complications of Culdocentesis
There can be various complications that might happen during a surgical procedure. These could include accidentally pricking the internal organs, the rectum, or the uterus. There might also be puncture of blood vessels, cysts, or tumors. If you have an ectopic pregnancy (when a fertilized egg grows outside the uterus), it could accidentally be withdrawn during the procedure. This could also happen with infected cells or cells carrying cancer, potentially spreading the infection or cancer to other parts of the body.
What Else Should I Know About Culdocentesis?
When fluids are taken out from the body for examination, the fluid can be looked at under a microscope and also used to grow bacteria for better understanding of the infection. Sometimes, when the fluid comes from a particular area in the lower part of the body (known as the pouch of Douglas), the blood doesn’t clot if it’s due to internal bleeding. However, when the bleeding is quite heavy, the blood can clot.
For this type of procedure, a successful test is determined by how much of your blood is made up of red blood cells, also known as a hematocrit. When it is 15% or higher, the test result is positive. If the extracted fluid is either too clotted or there’s no fluid at all, the test will not provide a clear diagnosis. If by accident a blood vessel is pierced during the procedure, that can lead to blood clotting.
There may be situations where the test results come out negative, but that doesn’t always mean there is no problem. Certain conditions like an unruptured outside-the-womb pregnancy, or a damaged Pouch of Douglas due to other health conditions such as endometriosis or inflammation in the pelvis, can lead to a false-negative result. In the case of outside-the-womb pregnancies, the distance from the uterus can affect the amount of bleeding that occurs – bleeding can be less if the distance is more and vice versa.
A study conducted back in 1998 aimed to figure out how well this fluid extraction test compares to ultrasound for detecting internal bleeding. The study involved 46 patients, 40 of whom had an outside-the-womb pregnancy. The results showed that ultrasound was more accurate and reliable in identifying internal bleeding compared to the fluid extraction test. Because ultrasound tests showed more consistent and precise results, the fluid extraction test is no longer the preferred method for diagnosing internal bleeding.
