[Monitoring of hemostasis during liver transplantation: contribution of thromboelastography]

Maniabilité et intérêts potentiels du thromboélastomètre modifié (Rotem™) dans le monitorage extemporané de l'hémostase en réanimation

OBJECTIVE

Preliminary assessment of a rotary thromboelastometer (Rotem) in the haemostasis monitoring in ICU.

STUDY DESIGN

Prospective, open.

PATIENTS AND METHODS

The device: the Rotem is a rotary thromboelastometer, which measures continuously and retranscribes numerically viscoelastic properties of a clot after an in vitro haemostasis activation. 83 patients with various haemostasis disorders that 122 blood samples have been subjected to a double analysis: extemporaneous by Rotem and at the laboratory for conventional haemostasis tests (aPTT, PT, fibrinogen, platelets). We assessed Rotem's manipulation duration, time for the first results. We compared Rotem variables with conventional haemostasis parameters and haemostasis diagnosis with each method.

RESULTS

Mean Rotem manipulation duration was measured at 2 minutes 51 seconds+/-1 minute 48 seconds and time for results at 13+/-6 minutes. Plasma fibrinogen level was strongly correlated with the kinetic of clot formation (CFT) and the maximun clot firmness (MCF) measured by Rotem (R>0.7, coefficient of Pearson). Platelets were strongly correlated with MCF. The PT and aPTT had a weak correlation with Rotem parameters (R< or =0.53). The diagnosis concordance between the two techniques was good with a pondered kappa coefficient measured at 0.68. Hypocoagulability thromboelastographic profile with Rotem was in agreement with conventional parameters diagnosis in 92 percent of cases. Hypercoagulability thromboelastographic profile was associated with a significant increase of conventional parameters (supranormal value in 78%). Normal thromboelastography profile was associated with normal conventional parameters in 49%. Different reagents used on several simultaneous tests specified the thromboelastographic diagnosis. A diagnostic algorithm showed the interest of the Rotem for the prediction of conventional test results.

CONCLUSION

Rotem is an easy manipulation device whose concordant and rapid results allow its emergency use in the framework of haemorrhagic situations. It also allows an approach of hypercoagulability states so that the therapeutic implication remains to evaluate. The Rotem offers a dynamic multifactorial approach on total blood of haemostasis that is what makes it a prime aid of haemostasis monitoring, in complement of usual analytic haemostasis evaluation.

Pediatric resuscitation in the operating room

The resuscitation of pediatric patients undergoing anesthesia involves appropriate administration of fluid and blood products and stabilization of vital signs. Crystalloid is first-line therapy for fluid resuscitation, and should be given with awareness of its potential dilution of the child's hematocrit. Many alternatives to homologous blood transfusions now exist, however, when necessary for increasing oxygen-carrying capacity or treating coagulopathy benefits likely outweight the risks. The risks for such transfusion include infectious, hemolytic, metabolic, and immunologic effects. When fluid and blood administration does not stabilize the patient, the differential diagnosis of hypotension, arrest, or arrhythmias must include medication errors, anesthetic overdose, electrolyte disturbances, hypoxemia, ventilatory problems, and surgical insults, including medications given in the operative field. Resuscitation should include treatment of hypocalcemia and hyperkalemia, chest compressions, and the administration of epinephrine when necessary.