Anesthesia view of hematuria associated with cell saver use during scoliosis surgery.

Sir,

Surgical correction of scoliosis involving metallic fixation of the vertebral bodies is associated with extensive blood loss. Cell saver is commonly used in scoliosis surgery as a mean of salvaging and returning the patient's red blood cells. We present a case of transient a symptomatic hematuria following cell saver use in scoliosis surgery. A 14-year-old female patient presented with scoliosis (t4-l3) level. She was booked for scoliosis correction.

The patient was healthy with normal preoperative lab results (blood work up and urine). Her medical history, as well as family history, was unremarkable.

After IV induction of general anesthesia, invasive monitors were smoothly and safely inserted without any injuries or excessive bleeding. Cell saver was used during the surgery and 300 mL of blood filtered through cell saver given back to the patient; followed by another 100 mL of blood was given as well as one unit of packed red blood corpuscles (PRBCS) was cross matched and transfused to the patient by the end of the procedure. Throughout the operation, the vital signs remain stable, but gradual change of the urine color to pink, darker pink than to red was noticed in the urine bag. Close monitoring was performed, the patient remains vitally stable and she recovered smoothly from anesthesia without any complications.

Even though it is a safe procedure to use cell saver devices, we recommend a special caution to be taken as it has the potential for a transient hematuria that may not alarm the doctors or nurses.

Substantial blood loss and the requirement for blood transfusion remain major considerations for prolonged spinal surgeries. Surgical correction of scoliosis involving metallic fixation of the vertebral bodies is associated with extensive blood loss.[1] Excessive blood loss not only increases the operative time but also increases the risks of allogeneic blood transfusion. The extensive use of pre, intra- and postoperative red blood cell salvage and autologous blood transfusion has been highly effective in reducing blood loss and transfusion requirements.[2]

Cell saver is commonly used in scoliosis surgery as a mean of salvaging and returning the patient's red blood cells.[3] The major advantages of cell saverinclude rapid availability, reduction of exposure to infectious agents transmitted by homologous blood transfusion, and a decrease in immune modulation.[4] However, the efficacy of cell saver use in pediatric spinal deformity surgery is unclear. In addition, there are reported complications with cell saver usage in pediatric patients, including concern for reinfusion of heparin zed blood leading to altered homeostasis, and alteration in electrolyte balance, and transient hematuria.[5]

Recently it is reported that processing of cardiotomy blood with a cell saver in patients undergoing cardiac surgery resulted in an increase in postoperative bleeding and greater use of allogeneic blood products.[6]

We present a case of transient a symptomatic hematuria following cell saver use in scoliosis surgery. A 14-years-old female patient presented with the scoliosis (t4-l3) level. She was booked for scoliosis correction orthopedic spine surgery.

The patient was healthy with normal preoperative lab results (blood work up and urine). Her medical history, as well as family history was unremarkable. She has neither history of medication nor hospitalization. She is not known diabetic, hypertensive, or allergic to any substances.

After IV induction of general anesthesia, invasive monitors were inserted include arterial line, central venous line, and urinary catheter. As well as 2 (16G) peripheral cannulas, and body warmer. All procedures were smooth without any injuries or excessive bleeding. Cell saver were used during the surgery and 300 mL of blood filtered through cell saver given back to the patient; followed by another 100 mL of blood was given. One unit of packed red blood corpuscles (PRBCS) was cross matched and transfused to the patient by the end of the procedure. Throughout the operation the vital signs remained stable, but gradual change of the urine color in the urine bag to pink; darker pink then to red was noticed. No bleeding or petechial hemorrhages were noticed. Close monitoring was performed, the patient remains vitally stable and she recovered smoothly from anesthesia without any complications. The patient was shifted to the post anesthesia care unit (PACU) then to word. Few hours later the urine became clear spontaneously. The patient developed transient asymptomatic hematuria after infusion of filtered blood and PRBCS. The hematuria disappeared spontaneously after few hours. Review of the preoperative causes of hematuria in nonurological cases reveals no interference with the urinary system. Moreover, there was no urethral trauma during catheter insertion. Blood pressure was stable all through the operative course that rules out the possibility of shock and eventual hematuria.

Hemolysis of the filtered blood may contribute to the development of hematuria. Hemolysis during collection with cell saver use may be caused by several mechanisms that may include the smaller diameter suction device that is used to “skim” blood from a large surface in spine surgery. This technique causes more mechanical trauma and aspirates air, increasing the amount of blood-air interface that promotes cell rupture.[7] Furthermore, hemolysis can be induced by irrigation with hypotonic fluid, excessive suction pressure >100 mm Hg, aspiration of clotted blood, and cell rupture can be caused by the collection of blood with povidine iodine, alcohol, hydrogen peroxide, and bone cement. All can lead to hemolysis.[89]

In spite of the safe use wide of cell saver in scoliosis surgery complications that ranges from mild to severe or life threatening have occurred.[10] Hematuria is rare complication but not uncommon in 1997 a case of the patient who had life-threatening disseminated intravascular coagulation (DIC) was reported, in spite of the multiplicity of the predisposing factors, but the use of the Intraoperative blood salvage was among the major ones.[11]

Keverline and Sanders reported earlier three patients with transient hematuria associated with the use of intraoperative salvage and reinfusion in different pediatric orthopedic operations. It was thought to be caused by a direct insult to the kidneys by the return of poorly washed blood.[12] In a study of five intraoperative autologous transfusions (IAT) devices when used in cardiac surgery, free hemoglobin in the collection reservoir ranged between 49.9 and 4689.9 mg/L (mean of 651 mg/L, demonstrating hemolysis with the collection process indicating that the centrifugal processing, and washing does not remove all stoma-free hemoglobin.[9]

A recent study reported the usefulness of used of cell saver in significantly decreasing postoperativeneed for blood transfusion. Furthermore, they described number of factors to be considered as significant parameters in predicting intraoperative blood loss.[13]

Even though it is a safe procedure we recommend special caution must be taken while using cell saver devices in patients as it has the potential for light transient and asymptomatic complication.