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Investigation: since this is a retrospective review of 938 erythrapheresis in children with sickle cell disease from 1 january to 31 december 2020, the disposable sets were not available for return.Red cell exchange on cell separators are used in the child with sickle cell disease and effective in lowering hemoglobin s level.Of the 938 apheresis performed in 2020 in our unit, we observed a low rate of procedural failure and few complications.Ninety-six percent of erythrapheresis was performed as part of chronic exchange programs, in more than 80% of cases for cerebral vasculopathy or after the onset of ischemic strokes.Less than 4% of the procedures were performed for specific indications (preparation for cholecystectomy most often).The approaches are rarely an obstacle to the realization of the apheresis.In case of insufficient venous capital, the placement of an arteriovenous fistula may be considered.Depending on the child's weight, hemoglobin level and the severity of the sickle cell anemia, precautions may be necessary when initiating the procedure.Nurses experienced in pediatric apheresis and a good medical knowledge of sickle cell disease allowed us to use this technique from the age of 3 years and the weight of 15 kg.The pediatric apheresis unit (umtc) is attached to the sickle cell reference center at the robert-debré hospital in paris, a center which follows around 2000 sickle cell children.This reference center is also a referral center for skill centers in north-eastern paris, where the population of sickle cell patients is constantly increasing.This unit, created in 2015 in response to the growing need for transfusion exchanges, brought together in one place manual transfusion exchanges, erythrapheresis and other pediatric apheresis (photochemotherapy and cell sampling).The combination within the same service of the two exchange techniques has caused over the years the switch from manual exchanges towards apheresis (fig.1).We resumed all the exchanges by apheresis carried out over one year in order to assess the characteristics of the pediatric population that we treated.From 1 january to 31 december 2020, 938 erythrapheresis were performed.Eight procedures were stopped early due to problems with the access routes, for a failure rate of 0.8%.Nine hundred and four of these procedures concerned 103 children in a chronic transfusion exchange program, 26 procedures were ad hoc exchanges.In 2020, these ad hoc exchanges were less numerous than in other years (around 50% less) due to the health crisis because they usually concern exchanges carried out before a scheduled surgical intervention.They were distributed as follows: 18 for cholecystectomy (69%), 4 for tonsillectomy (15%), 4 for pre-marrow transplant (15%), 2 for other surgery and one for acute chest syndrome.For the patients in the chronic exchange program, the indications were as follows: 87 for cerebral vascular disease or ischemic stroke (84.4%), 8 for severe vaso-occlusive crises despite treatment with hydroxyurea (7.7%), 4 for prevention of vaso-occlusive complications during corticosteroid therapy (3.9%) and 4 for severe organ damage (3.9%).The children were aged 3.3 to 19.3 years (median 11.8 years) (fig.2), weighing 15.3 to 85.8 kg (median 37.7 kg) (fig.3).The routes of entry used were arteriovenous fistulas for 13 of 103 chronic exchange patients (12.6%).For all other procedures, the peripheral channels are used with cathlons of 20 or 22 gauges most often, sometimes 24 gauges.The cell separators used are spectra optia from terumo or com tec from fresenius, chosen according to the need or not for an initial depletion and the weight of the patient.The volume of red blood cells exchanged averaged 27.8 ml / kg, adjusted for each procedure depending on the indication for the exchange, hemoglobin level and hemoglobin s level of the day.When an initial depletion is desired, it is compensated by physiological serum and calculated for a minimum hemoglobin greater than or equal to 8 g / dl.The target hematocrit was programmed to reach a target hemoglobin between 9.5 and 10.5 g / dl.This target was reached in 93% of cases.The treated blood volume is most often less than a blood mass for a median procedure duration of 85 minutes (minimum 43 minutes, maximum 177 minutes) (fig.4).The undesirable effects related to the procedure were as follows: vagal discomfort was noted 17 times, i.E.A frequency of 1.8% of erythrapheresis, the most frequent manifestations of these discomforts being abdominal pain and secondary drowsiness, with or without sweating and mucocutaneous pallor.This impact is probably underestimated, some discomforts occurring after leaving the service.Two transfusion incidents have been reported: an allergic reaction with dyspnea and an episode of hyperthermia shivering.The anticoagulation used has always been acd-a alone, no adverse effects linked to citrate have been observed.The difficulties mentioned in performing apheresis in children are often the route of entry.In our experience we often have more difficulty with adolescents with impaired venous capital than with underweight children.The use of small caliber cathlons (" yellow ", 24g) can allow a flow sufficient for apheresis of reasonable duration either in bleeding or in return.Our procedure failure rate has decreased significantly with the experience of our nurses and the introduction of systematic warming and hydration upon arrival of the patient on the ward.The use of arteriovenous fistula is known for these procedures [5], the complications described in sickle cell patients are thrombosis and infections.We had no complications in 2020, but the complications that we have had to deplore over the past 5 years are thromboses requiring recanalization.The second obstacle may be the volume of the extracorporeal circuit of the kit in relation to the total blood volume of the child, which could pose problems of hypovolemia or anemia at the initiation of the ring.Since the separators operate almost permanently in isovolaemia (to within 30 ml), good hydration of the child with physiological serum before the exchange is sufficient to maintain an adequate volume.In the event of anemia which risks lowering the hematocrit too much at priming, it is possible either to transfuse the child before the exchange or to perform a personalized priming (possible on the optia).To avoid variations in hematocrit that could have an impact on cerebral perfusion, we do not do an initial depletion in children weighing less than 25 kg or in patients with severe vasculopathy or who have had a recent vascular accident.With the same aim of avoiding excessive variations in the hematocrit, we prefer to use the priming with albumin on the optia, rather than with a red blood cell pellet in the event of anemia requiring priming.Personalized.The occurrence of vagal discomfort after apheresis is usually even in children without seriousness.They require continued iv hydration and a few additional hours of hospitalization.These occur in children of all ages, weight and both sexes.They are often repeated in the same patients.The prevention of recurrence is based on iv hyperhydrataion in pre and post exchange.They seem to be favored by voluminous exchanges (> 30 ml / kg) with initial depletion.Since the child has difficulty expressing signs of hypocalcaemia, we prevent the side effects associated with the use of acd by continuously infusing diluted calcium gluconate in the return route during the procedure.In the event of hypomagnesemia on the initial assessment, oral supplementation is made pre- and post-exchange.Each transfusion incident is the subject of a significant haemovigilance declaration in sickle cell patients particularly at risk of alloimmunization and severe transfusion accident.We did not observe any hyperhemolysis syndrome in this series, but we can see that the so-called exchange indications ¿comfort ¿ (before travel or examination, for example) have almost disappeared since the increase in the description.Of these transfusion accidents [6].The occurrence of a severe adverse reaction was not observed in this series, but in a child with progressive unstable vasculopathy, the occurrence of a vascular accident after transfusion exchange is possible.In our experience it can occur as well after an exchange in manual technique as after an apheresis.Since this is a retrospective review of 938 erythrapheresis in children with sickle cell disease from 1 january to 31 december 2020, the lot numbers were not provided; therefore, a disposable lot history search could not be conducted.According to therapeutic apheresis: a physician's handbook, adverse events occur during therapeutic procedures with a frequency of 4.8%.Vasovagal incidents occur around 0.5% of procedures.The reactions generally manifest as pallor and diaphoresis.In a full blown attack, the reaction progresses from pallor and sweating to pulse slowing and blood pressure decreasing.More severe vasovagal reactions may include nausea, vomiting, and/or convulsions.The most common reactions were fever (7.7%), urticaria (7.4%), hypocalcemic symptoms such as facial paresthesias (7.3%), pruritus (5.8%), tachycardia (5.6%), and mild hypotension (5.6%).According to therapeutic apheresis: a physician's handbook, adverse events occur during therapeutic procedures with a frequency of 4.8%.Symptoms of allergic reactions may include hives, dyspnea, wheezing, burning eyes, tachycardia, hypotension, and or facial swelling and flushing.Mild reactions can be treated with diphenhydramine administered through an iv.According to therapeutic apheresis: a physician's handbook, adverse effects related to vascular access are a frequent concern.Hemorrhage or pneumothorax or both may complicate cvc insertion, while thrombosis and infection are the most frequently observed complications of prolonged central venous access.During a dressing change, the site should be cleaned and observed for signs of infection such as redness, swelling, drainage, and foul odor.If an infection is suspected, cvc removal should be considered, and the patient should be treated for infection as appropriate.The cause of a cvc flow problem may sometimes be difficult to determine, although patient repositioning will sometimes improve flow.A common situation is that the cvc can be flushed without resistance but does not yield blood return; this scenario may be the result of kinking, poor positioning, intralumenal clots, or venous thrombosis.Blocked cvcs can sometimes be cleared with a fibrinolytic agent such as tpa.The placement of a cvc is considered by some to be the greatest risk related to the apheresis procedures, and it should be avoided if the procedure can be performed using peripheral iv.Article citation: lesprit e, et al, érythraphérèses chez l¿enfant drépanocytaire, expérience d¿une unité d¿aphérèse pédiatrique, transfusion clinique et biologique.Https://doi.Org/10.1016/j.Tracli.2021.09.002 root cause: a root cause assessment was performed for the vasovagal reactions.Vasovagal are common side effects of therapeutic apheresis procedures.They are typically caused by the patient's disease state, the rate of ac infusion, the length of the procedure, the patient's sensitivity to the procedure and/or the hemodynamic stress of the procedure.A root cause assessment was performed for the allergic reactions.Based on the available information a definitive root cause could not be determined but it is likely due to one or a combination of the possible causes listed below: * patient's sensitivity to the replacement rbcs * patient's sensitivity to the ethylene oxide used to sterilize the disposable set a root cause assessment was performed for the complications of thrombosis and infections.The authors attributed the cause to the patients' arteriovenous fistula.
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