Cesarean section is the most common surgery performed in the United States; nearly one third of all deliveries are cesarean sections, according to the Center for Disease Control. Bleeding can occur from the uterine or skin incision, from the placental attachment site, or from a nicked or damaged blood vessel. Blood loss from cesarean section may be twice that lost in vaginal delivery, according to the Encyclopedia of surgery; so, additional internal bleeding can rapidly lead to hypovolemic (low blood volume) shock.
Vital Sign Changes
Tachycardia, or rapid heartbeat over 100 beats per minute, is a classic sign of internal bleeding and hypovolemic shock. Because the blood volume drops, blood pressure to less than 90 mm Hg systolic. Breathing may become rapid and gasping, with respiration of 22 minute or more, according to the Merck Manual.
After delivery by cesarean section, all women are given a medication called oxytocin to help the uterus contract and stay firm, so bleeding doesn't occur. If the uterus loses its tone, and becomes flabby, it's called uterine atony, or a "boggy" uterus, and large amounts of internal bleeding can occur rapidly, according to David Miller, M.D. For this reason, the uterus is felt manually through the abdomen every hour or so for the first few hours after delivery.
The uterus is generally felt between the public bone and the navel after a cesarean delivery. If the uterus begins to be palpated at a higher level each time it's checked, it may be filling up with blood. Bruising or a bluish tint to the skin below the navel may also be seen if internal bleeding occurs. The abdomen may become hard, distended or painful to touch.
Women with internal bleeding become very pale. Hands and feet may be cold and clammy, the woman may be very sweaty, and capillary refill time, which is checked by pushing down on a fingernail and watching to see how fast the blood returns to the nail, is slow, according to the Merck Manual.
Weakness and Anxiety
Women with internal bleeding may complain of being weak, or may even pass out, especially if they try to stand up. Feelings of anxiety and an impending sense of doom are common during an episode of internal bleeding, according to the Merck Manual.
Because the cervix is soft and often somewhat dilated, or open, even after a planned cesarean delivery, blood can escape through the vagina. Women who have had cesarean sections still have vaginal bleeding, called lochia, from the placental site after delivery. However, if bleeding becomes heavier than normal, saturating a pad an hour, or if large clots are passed, internal bleeding should be considered.
Decreased Urine Output
Because blood flow to the kidneys is reduced, urine output may fall to less than 30 milliliters (ml) per hour, according to the Merck Manual. Most women have a foley catheter inserted for a cesarean delivery to keep the bladder empty, and the urine output is checked every hour for the first few hours after delivery.
A complete blood count, or CBC, may show a decrease in hemoglobin or hematocrit, although this won't show up on a blood test immediately in the case of rapid blood loss, according to the Merck Manual.