A Story About Hemolytic Uremic Syndrome (HES)
The month of August is for me a time of remembrance. My wife and I just celebrated our 26th anniversary. I am surprised and thankful that she has put up with me and the life of a perfusionist for the past 26 years. You know, missed birthday parties for your kids, missed anniversary dinners, missed school functions, etc. “It is amazing how fast time flies”— I always thought this was just a corny line used by old people like my parents and grandparents. Now it has become part of my repertoire, as I speak to my own children as they come and go from college life. But you know, sometimes anniversaries are not always happy and joyous; sometimes they bring sorrow and pain. Some events are still etched within the recesses of your memory, and spring forth uninvited when the calendar rolls around . . .
My first encounter with the beautiful two-year old little girl was a shy wave of the hand returning my smile and wave at her through the glass enclosed room as we, the medical staff attending grand rounds on August 14, 1997, discussed her case presentation.
She had presented at another facility in the Denver area with a history of three days of bloody diarrhea and mild fever. She had been transferred to our facility the previous night with a 39,000 white blood count, 21,000 platelet count, hematocrit of 34%, BUN of 19, Creatine 0.7, and serum Sodium of 122. She remained oliguric and somewhat dehydrated, receiving intravenous fluids.
The presumptive diagnosis was Hemolytic Uremic Syndromehus (HUS) and a decision was made to place a central access venous line for plasmapheresis, which was started within 10 hours of admission.
On day # 1 at our facility, we received the culture report from the first hospital this child visited which revealed Escherichia coli 0157:H7, a particularly virulent strain. On this day her BUN was 68, Creatine 2.2 and the decision was made to place a peritoneal dialysis catheter to facili3te removal of the accumulating byproducts of metabolism. During the surgical procedure to place this catheter, approximately 300mls of ascitic fluid was drained from the abdominal cavity.
By day # 3 the decision was made to switch from peritoneal dialysis to hemodialysis due to increasing difficulty with the removal of peritoneal lavage fluid and concern over another spike in temperature. She remained on a schedule of daily plasmapheresis.
On day # 4 she had to be intubated and concern over possible seizure activity was voiced by the nursing staff. By midnight her condition had worsened with lower blood pressure and addition of a Dopamine drip at 7mcg/kg/min. I received a call from the pediatric intensivist, alerting me to potential ECMO, and began the drive into the hospital. While enroute, the patient suddenly went into cardiac arrest. I arrived at the PICU and quickly set-up and primed the ECMO circuit while the cardiovascular surgeon cannulated the right neck vessels. The cardiac echo, performed shortly after initiating ECMO, revealed depressed myocardial function (LV ejection fraction of 30%). This was thought to be due to endotoxin-induced depression.
The ECMO circuit consisted of: Avecor 1500 membrane, Minntech HPH 400 hemoconcentrator, “standard” ECMO circuit employing a Gish 30 ml bladder, and a Stockert/Sorin computer assisted perfusion system (CAPS). A 12 Fr BioMedicus cannulae was placed into her aorta via the right carotid artery and a 14 Fr BioMedicus cannulae in her right jugular vein and positioned into her right atrium.
The patient was stabilized on ECMO within the first 8 hours following administration of sufficient blood products to reach appropriate hemostasis and achieve activated coagulation times of 180-220 seconds. The dopamine was reduced to renal levels (3 mcg/kg/min) and dialysis was instituted via the ECLS circuit and our hemoconcentrator filter. We continued to provide access for daily plasmapheresis via the bladder (pre-membrane/venous) and post-membrane/arterial sampling ports for return of the “cleaned product.”
By day #3 of ECMO support, the patient exhibited more generalized edema (anasarca), intermittent chattering of the venous line as we incurred difficulty with adequate venous drainage, and increasing need for volume administration to maintain appropriate mean arterial pressures (MAP). It was decided to add low dose Epinephrine (0.1mcg/kg/min) to maintain her MAP and minimize the addition of more volume.
On day # 4 of ECMO support, we continued to have intermittent problems with venous drainage and had gradually increased the Epinephrine drip to (0.4mcg/kg/min) to maintain MAP greater than 35 mmHg. We began to battle increasing metabolic acidosis, despite excellent oxygenation and carbon dioxide removal. There was increasing concern over “dying/dead” bowel that could be causing the acidosis and increasing girth of the abdomen. It was reluctantly decided to perform an exploratory laparotomy while on ECLS in the PICU.
The surgeons noted “significant areas of ischemic and gangrenous bowel” which were resected. The abdominal cavity was thoroughly irrigated with copious amounts of antibiotic-laced irrigation fluid and partially closed with drains and retention sutures and mounds of dressing material.
On day # 5 of ECMO support we continued to battle excessive fluid/blood loss from the abdominal cavity, intermittent chattering of the venous line due to the tremendous girth of the abdominal cavity and decreasing venous return to the right side of the heart, multiple blood product transfusions, and increasing pharmacological support for the failing heart and body’s perfusion. The parents and the medical staff elected to withdraw ECMO support during the early afternoon, and the patient expired within 5 minutes.
The post mortem examination revealed: “Hemolytic Uremic Syndrome with E.coli septicemia, acute renal failure, necrotic colitis, ascites, thrombocytopenia, cerebral edema.
