With the right care, mare and foal can survive this critical event.
The first step in the decision to do a Caesarean section is that all other forms of help have been exhausted. Often, C-section candidates have already been in labor for quite some time on the farm, where manual manipulation has been tried. If it takes very long to haul the mare to the clinic for possible surgery, that adds even more time to the labor. However, C-sections are major surgery and most veterinarians and mare owners would prefer to manually assist the foal (alive or dead) through the birth canal rather than have to operate. Regardless, it is important to note that the mare's reproductive tract can be damaged easily, and C-section is frequently the best option for the well- being of the mare if the foal cannot be delivered within 20 minutes.
Anthony Blikslager, DVM, PhD, Dipl. ACVS, interim department head and associate professor of equine surgery at North Carolina State University's (NCSU) College of Veterinary Medicine, says with a C-section, getting a live foal will depend on how quickly the emergency surgery is performed once the mare goes into labor.
"Since we are a referral hospital, usually by the time the mare gets here the foal is already in critical condition or dead," he says. "We are often just trying to save the mare. There are some referral centers where the horse population is close to the hospital and they more frequently have a live foal to work with. The trouble is, once a mare goes into full-blown labor, you typically have only 30 to 60 minutes to get the foal out. It might take that long, in many regions, just to get your veterinarian to the farm."
Teamwork and Speed
"Once a mare gets to the hospital, regardless of whether the foal is alive or not, we go through a set routine to try to save the few that show up with live foals and make sure we also save the mare," says Blikslager. "If a mare shows up with a dead foal and you take too long trying to pull the foal, the mare will go into shock and you may lose her, too."
Joanne Kramer, DVM, Dipl. ACVS, clinical assistant professor of equine surgery at the University of Missouri, says if the mare has been in labor more than an hour, survival of the foal is unlikely. "Even if the foal is dead, however, the prognosis for mare survival is good if her systemic status is not severely compromised," she says. "Conditions that decrease her chances for survival include uterine rupture, endotoxemia, uterine bleeding, and retained placenta."
--Heather Smith Thomas
There are four teams called into work with a potential C-section candidate: the reproductive people, the surgical group, the anesthesia team, and the neonatal team (the group that deals with the foal). A veterinarian performs an examination of the mare to see what shape she's in upon arrival. A technician puts a catheter in a vein to give medications and fluids. Meanwhile, a member of the reproductive team puts an arm into the birth canal to see what position the foal is in, and if it is still alive.
Mike Whitacre, DVM, MS, Dipl. ACT, associate professor of theriogenology and head of the theriogenology group at NCSU, is the reproductive specialist who works closely with Blikslager on these emergency cases. "What we usually do, after I make my first evaluation of the mare, is decide whether we can possibly deliver the foal without going to surgery," says Whitacre. If surgery is necessary, the mare goes to surgical prep immediately.
If the veterinarian doesn't feel surgery is required yet, the next step is often to anesthetize the mare so the situation might be resolved with manual manipulation. Blikslager says, "Within a few minutes of her arrival, she is put into our padded area where we can induce anesthesia--to keep her from straining or feeling pain. We initially lay her on her side and put hobbles on her back ankles so we can winch her hind end off the ground. Having her hind end up helps with repositioning the foal, with her abdominal weight falling away from the back end."
He said the main thing that prevents repositioning a foal is the need to push it back in to maneuver it at the same time the mare is trying to push it out. "The forces of labor are so strong in horses that even an epidural doesn't make much difference; nothing short of anesthesia will stop it."
Whitacre says not every mare is anesthetized. "If we think we can tranquilize her and make a minor manipulation and deliver the foal, we go ahead and do that," he says.
After the mare is anesthetized, the teams spend a set period of time trying to get the foal out, notes Blikslager. "From the time the mare hits the ground until the time she goes into the operating room should be only 30 to 40 minutes," he says. "You need a separate person timing it, because the clinician will try and try, not realizing how much time has elapsed, and by then the mare could be seriously compromised."
Whitacre says most of the cases can be resolved after the mare is anesthetized, and only a small portion of them have to go to surgery. "Once we get the mare anesthetized so she stops straining, we may be able to reposition the foal," says Whitacre. "We may winch her rear quarters up because it gives us more working space, but we don't leave her winched up because it compromises her breathing."
Decisions To Make
One factor that comes into the sequence of events is the owner's finances. It's a three-tiered approach--first to check the status of the foal with the mare standing, then talk to the owner if the mare needs to be immediately anesthetized. If manipulating the foal with the mare anesthetized doesn't work, she might need surgery. On occasion an owner might not be willing to go to the expense of a C-section, and a fetotomy (removal of the dead foal a piece at a time) might be performed instead.
Blikslager says, "The C-section cost may go up to $3,500 (including initial exams, preps, medication, anesthesia, surgery, and aftercare). The owners may tell us they can afford to have us anesthetize the mare and try to get the foal out, but can't afford the C-section. In that instance we would push that second stage longer and more aggressively than if they'd given us the option to go ahead with a C-section. And at this point we would also consider a fetotomy to save the mare."
James T. Robertson, DVM, Dipl. ACVS, associate professor of equine surgery at The Ohio State University, explains that a fetotomy always carries risk for damaging the mare, particularly her cervix. However, it can be done safely by someone practiced in the procedure. "It involves putting a large instrument in there to cut up the fetus, and if it takes more than one or two quick cuts, you put the mare at risk," says Robertson. "If it's a valuable broodmare, you are better off doing the C-section."
The C-Section Surgery
If a decision is made to go to surgery and the mare is already anesthetized, she merely needs to be moved to the operating room. Careful anesthetic management is important, especially if the foal is still alive. The mare must be well-oxygenated to maintain the foal's oxygen supply.
Before she goes into surgery, the team gives her antibiotics. "The best time to prevent an infection is before you even start surgery," says Blikslager. "We usually give anti-inflammatory medication as well."
Blikslager says, "We (clip and) surgically scrub the whole belly and make an incision on the midline, as for a colic surgery, except this incision goes clear to the udder. The colic incision usually starts at the navel and works forward."
Robertson says some of the earlier C-sections (done in Europe) were through the flank, which doesn't work as well. "You need a long incision, and the easiest access and easiest way to control everything is doing it through the bottom of the abdomen," says Robertson. "Some mares have edema (fluid swelling) around the udder, but you deal with that; you just have to contend with a little more bleeding."
Blikslager says, "As soon as we get through the belly wall, we look for the gravid (pregnant) horn of the uterus, containing the foal. We pull that up out of the incision as much as we can. Then we put sterile towels around that gravid horn, because when you cut into it there will be some leakage of fluid. We want that to be soaked up by a towel and not get back into the mare's belly."
Robertson explains that if there have been any prior attempts to manipulate the foal, this fluid could be contaminated and harmful to the mare.
Blikslager says, "We try to find a back or front leg of the foal, to help us position the incision--because you want to cut right over the top of one of the legs. We make a 15- to 20-centimeter incision through the wall of the uterine horn."
The incision should be about as long as the distance between the foal's foot and his hock, so he can come through it without ripping a larger hole in the uterus, explains Robertson. "The incision is made in an area along the horn where there is not as much blood supply and not too close to the main body of the uterus," says Robertson. "You try to also select an area that will be easy to suture."
Blikslager says once the uterus is open, the team puts obstetrical chains on the ankles to elevate the foal out of the incision.
"If the foal is alive, a team puts the foal on a gurney that already has an oxygen cylinder on it, and they start working immediately on the foal," Blikslager says. "Meanwhile, I am busy cleaning up the surgical site, and closing up the incision in the uterus."
Robertson explains that the initial step is to run a continuous suture around the edges of the uterine walls. "A mare can bleed to death if you don't put that stitch around the opening," explains Robertson. "You are basically squeezing the whole edge to reduce the likelihood of significant bleeding. The surgeon generally does at least a two-layer closure on the uterus, taking the edges and inverting them a little. The whole time you are working on it, the uterus is shrinking (returning to its nonpregnant size), if it's healthy."
Blikslager says surgeons usually don't remove the placenta; it's better to let it come out vaginally. "We peel it back from the edges of the incision, just so we don't catch it with stitches," he says. "Then we usually get into a new surgical gown and rinse out the belly and close it up. If we had any question about whether there has been any intestine wrapped up or adjacent to the uterus or in trouble, we can look at that at the same time. Sometimes intestines nearby will get bruised. Sometimes we'll get a dystocia (difficult birth) that is also a colic. Or sometimes we'll get a dystocia in which the mare is having difficulty because the uterus is twisted, so we have to flip the uterus around and make sure the intestine didn't get caught up in it."
Chances for the Foal
The chances for having a live foal following a C-section vary greatly depending how long it takes to get the mare to the referral hospital.
If the foal survives the surgery, he'll need oxygen, because he needs to wake up from the anesthesia given to the mare. Robertson says in most cases a foal that is not already compromised by a long labor will come around pretty quickly. "Most hospitals put the foal on a foal bed--a big cushion where people can hold him," says Robertson. "You give him oxygen and apply mild antiseptic to his umbilical cord."
After a C-section the mare's colostrum production might be compromised, so the foal needs supplemental colostrum.
"The mare may have milk, but you are still better off giving the foal something immediately, whether it's colostrum or a commercial product," says Robertson. "We give it to him by tube as soon as he is awake, unless he is really good at sucking a bottle."
The mare is usually given oxytocin (a hormone that induces uterine contractions) to help her shed the placenta. "You can start it during surgery," says Blikslager. "After she recovers from the anesthesia, we hook it up again as a continuous infusion in her IV (intravenous line), or you can give it as multiple injections.
"We continue the antibiotics and Banamine after surgery, to prevent infection and try to reduce the effects of shock," says Blikslager. "We usually give a lot of IV fluids. Often these mares are already dehydrated when they come in."
Most of the mare's aftercare is geared toward avoiding shock, dealing with electrolyte imbalances, concern with placental health, and watching the mare carefully for complications such as peritonitis-- inflammation of the membrane lining the abdominal cavity that might result from leakage of fluid from the uterus, particularly if the foal has been dead for a while.
"Anytime a mare suffers shock associated with the uterus or a retained placenta, she is more at risk for laminitis than when shock is associated with other conditions (such as blood loss), so we have to watch out for that," says Blikslager.
Most mares recover well from C- section surgery. Whitacre says that on rare occasions, a mare has problems post- surgically from anesthesia, or she has problems getting up. Robertson says recovery in some mares can be tough because they are exhausted from prolonged dystocia. "If someone has been working in there and pushing at the foal, the mare may get a bit of paralysis and nerve injury," he notes. "She may be getting a little toxic, then has to undergo anesthesia, then you have to try to wake her up. The better shape she's in going into surgery, the more likely she is to recover."
Blikslager says, "We keep a close eye on the surgical incision for signs of infection. A mare will typically be in the hospital for five to seven days after a C-section. She'll be a couple of days in intensive care, then have a gradual weaning off all the medications and fluids. We make sure there is no laminitis and the uterus is contracting. The reproductive people come back each day and feel the uterus to make sure it's okay. Then the mare goes back home and continues recovery. She usually spends a month in a stall, then a month in a small paddock before returning to a normal exercise routine." Even if you can't save a foal, the mare can return to full reproductive health if she receives prompt surgical care and thorough aftercare.
Experience has shown that mares can have successful C-sections, produce live foals, and go on to full reproductive health. The key is early intervention by a skilled veterinarian who can help you make the right decisions for the safety and health of the mare and foal.
About the Author
Heather Smith Thomas ranches with her husband near Salmon, Idaho, raising cattle and a few horses. She has a B.A. in English and history from University of Puget Sound (1966). She has raised and trained horses for 50 years, and has been writing freelance articles and books nearly that long, publishing 20 books and more than 9,000 articles for horse and livestock publications. Some of her books include Understanding Equine Hoof Care, The Horse Conformation Handbook, Care and Management of Horses, Storey's Guide to Raising Horses and Storey's Guide to Training Horses. Besides having her own blog, www.heathersmiththomas.blogspot.com, she writes a biweekly blog at http://insidestorey.blogspot.com that comes out on Tuesdays.
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