Zhengyi Feng

Perioperative Monitoring of Thromboelastograph on Blood Protection and Recovery for Severely Cyanotic Patients Undergoing Complex Cardiac Surgery

In this study, we assessed the clinical effect of a new transfusion therapy guided by thromboelastograph (TEG) on blood protection. Thirty-one children with severe cyanosis (hematocrit ≥54%), who were diagnosed as having transposition of the great arteries or double outlet right ventricle with or without pulmonary valve stenosis, and underwent arterial switch operation or double roots transplantation, were involved and were divided into two groups. In group F (n=17), the transfusion therapy after cardiopulmonary bypass was performed with fibrinogen administration combined with traditional transfusion, guided by TEG. In group C (n=14), traditional transfusion guided by clinical experiences only was performed. We observed the blood protection effects and recovery conditions of these patients. In surgery, compared with group C, the chest closure time, fresh-frozen plasma (FFP), and platelet (PLT) volume used at closure time had no significant reductions in group F (P>0.05, respectively), and the patients in group F had no significant reductions in the amount of chest drainage (P>0.05). The total PLT and total red blood cells usage were also the same (P>0.05). But during the first 24h, FFP usage in the intensive care unit (ICU) and total perioperative FFP usage had significantly dropped in group F (P<0.05); the mechanical ventilator time, ICU stay, and hospitalization time in group F were much shorter than those in group C (P<0.05). So, TEG was effective in perioperative blood protection. Fibrinogen could be a substitute for FFP to restore hemostasis and improve the prognosis for these patients.

The myocardial protection of HTK cardioplegic solution on the long-term ischemic period in pediatric heart surgery.

Cardioplegic reperfusion during a long term ischemic period interrupts cardiac surgery and also increase cellular edema due to repeated administration. We reviewed the clinical experiences on myocardial protection of one single perfusion with histidine-ketoglutarate-tryptophan (HTK) for infants. This retrospective study included 118 infants who underwent open-heart surgery between January 2004 and December 2007. We divided the entire cohort into two groups: In group H (n = 63), myocardial protection was carried out with one single perfusion with HTK solution, and in group S (n = 55) with conventional St. Thomas crystalloid cardioplegia. The duration of cardiopulmonary bypass (CPB) did not differ between these two groups, but the duration of aortic cross-clamping time in group H was significantly shorter than that in group S (p < 0.05). During reperfusion, the spontaneous re-beating rate was higher in group H (p < 0.05). There were no differences in doses of inotropic agent and creatinekinase (CK) values on postoperative day 1 between these two groups, but the level of CK in group H was significantly less than that in group S on postoperative day 2 (p < 0.01). The mortality in group H was lower than in group S (p < 0.05). The HTK group had shorter cross-clamping time and more frequent spontaneous defibrillation than St. Thomas group. We propose that HTK is valid for some complicated cardiac surgeries with long term cross-clamping time.

Clinical outcomes and experience of 20 pediatric patients treated with extracorporeal membrane oxygenation in Fuwai Hospital.

The purpose of this study was to report retrospectively the summarized clinical findings from 20 consecutive pediatric extracorporeal membrane oxygenation (ECMO) patients and to investigate the factors associated with mortality. The ECMO circuit system was completely covered using heparin-coating technique, and venoarterial ECMO was used in all patients. Heparin dosage was 4–20 U/kg/h and active clotting time was maintained between 146 and 360 seconds. ECMO was weaned off successfully in 15 patients (75%); 11 of 15 patients (73%) survived and were discharged from the hospital; 4 of 15 patients died of postoperative complications; 5 patients failed to be weaned off ECMO. The percentage of discharged patients was 55% (11 of 20) in this cohort study. Lactic acid concentration of artery blood before ECMO in survivor patients was significantly lower than in nonsurvivor patients (p = 0.009); patient weight between two groups also had statistical difference (p = 0.046). ECMO effectively treats cardiac and pulmonary failure secondary to cardiac surgeries for complicated congenital heart diseases. Early application of ECMO in patients with cardiac and respiratory failure is still the key point of success in preventing vital organs from irreversible damage.

The effect of preprocessing stored red blood cells on neonates undergoing corrective cardiac surgery.

This study compared the effect of unprocessed and processed packed red blood cells (PRBCs) with the continuous autotransfusion system (CATS) during neonate heart surgery. Sixteen neonatal patients undergoing cardiac surgery were randomly divided into two groups: unprocessed PRBC (C group, n = 8); processed PRBC (P group, n = 8). The CATS was employed perioperatively. Series laboratory and clinical parameters, including levels of hematocrit, blood potassium, blood glucose, blood lactate, acid-base, and total priming volume of PRBC, were used to compare the effect between the two groups. Before CPB, the hematocrit of processed PRBCs in P group was significantly higher than those in C group (p < 0.01), and the concentrations of potassium, blood glucose, and lactate of processed PRBCs in P group were significantly lower than those in C group (p < 0.01). At the beginning and the end of CPB, the hematocrit levels in P group were all higher than those in C group (p < 0.05); lactate levels in P group were significantly lower than those in C group at the beginning of CPB (p < 0.01), and lower than that of C group at the end of CPB (p < 0.05). The total priming of PRBCs in P group was significantly less than that in C group (p < 0.01). Perioperative processing with CATS provided a high-quality RBC concentration, decreased the total priming of PRBCs, providing increased high-quality blood salvage during neonatal CPB procedure.

The influence of cardiopulmonary bypass priming without FFP on postoperative coagulation and recovery in pediatric patients with cyanotic congenital heart disease

Transfusion guidelines have been produced for the evidence-based use of fresh frozen plasma (FFP). However, the inappropriate use of FFP is still a worldwide problem, especially in the prophylactic settings. In the present study, 100 cyanotic pediatric patients (age 6xa0months to 3xa0years) undergoing cardiac surgery with cardiopulmonary bypass (CPB) were randomized to receive either 10–20xa0ml/kg FFP (FFP group, nu2009=u200950) or 10–20xa0ml/kg 4xa0% succinylated gelatin (Gelofusine, GEL group, nu2009=u200950) in the priming solution. Rapid thromboelastography (r-TEG) was measured before skin incision and 15xa0min after heparin neutralization. Postoperative renal and hepatic function, mediastinal chest tube drainage, transfusion requirements, and recovery time were observed. The relationships between hematologic and demographic data and postoperative bleeding volume were also analyzed. The results showed that there were significantly elevated levels of fibrinogen (r-TEG parameters: fibrinogen contribution to maximal amplitude (MAf) and fibrinogen level (FLEV)) in the FFP group compared to the GEL group. The postoperative blood loss, total transfusion requirements, and recovery time were not significantly different between the two groups, indicating that there were no obvious clinical benefits of using FFP in the priming. The maximal amplitude (MA) of r-TEG measured after heparin neutralization was correlated with the 6-h postoperative bleeding volume. In addition, preoperative fibrinogen level rather than FFP priming was an independent predictor of postoperative blood loss. Conclusion: Prophylactic use of FFP in the priming solution does not have obvious clinical benefits in cyanotic congenital heart disease (CCHD) patients. Gelofusine, an artificial colloid, is a safe and effective substitute of FFP in the priming solution. Furthermore, r-TEG can be used as a “real-time” assessment tool to evaluate postoperative bleeding and guide transfusion after cardiac surgery in pediatric patients.

Application of modified perfusion technique on one stage repair of interrupted aortic arch in infants: a case series and literature review.

One stage repair of interrupted aortic arch (IAA) associated with cardiac anomalies in neonates and infants is challenging for the entire surgical team. Deep hypothermic circulatory arrest (DHCA) prolongs myocardial and cerebral ischemia and may induce heart, brain, and major organ dysfunction. From May 2004 to May 2006, 13 infants with IAA underwent one stage repair by median sternotomy under DHCA with continuous regional cerebral perfusion (RCP) in Fuwai Children’s Heart Center. Median age at operation was 10.4 ± 6.7 months, and mean body weight was 6.58 ± 2.15 kg. Temperature of nasopharynx was decreased to 18°C–20°C; rectal temperature was controlled at 19°C–22°C. Flow rate of RCP was maintained with 20–25 ml · kg−1 · min−1 under DHCA combined with RCP. Mean artery pressure (MAP) measuring from right radial artery was 32.5 ± 5.8 mm Hg, and MAP from femoral artery was 11.2 ± 3.5 mm Hg. Mean cardiopulmonary bypass (CPB) time was 141.6 ± 21.7 min, and mean aortic clamp time was 52.3 ± 10.9 min. Mean duration of RCP was 31.5 ± 12.4 min. Mean intubation time in intensive care unit (ICU) was 54.7 ± 12.6 hours, and mean ICU stay was 67.9 ± 28.4 hours. This report describes our CPB protocol under DHCA using continuous RCP in low weight pediatric patients to minimize neurological complications during one stage IAA repair and summarizes the various CPB managements in recent literature as well.

Evidence-based use of FFP: the influence of a priming strategy without FFP during CPB on postoperative coagulation and recovery in pediatric patients:

Objective: Although fresh frozen plasma (FFP) is one of the most commonly used hemostatic agents in clinical specialties today, there is little evidence available supporting its administration. Our present study observed the effects of a priming strategy without FFP during cardiopulmonary bypass (CPB) on postoperative coagulation and clinical recovery in pediatric patients, aiming to supply new evidence for evidence-based use of FFP. Method: Eighty pediatric patients with congenital heart disease undergoing cardiac surgery with CPB were randomized to receive either 10-20 ml/kg 4% succinylated gelatin (Gelofusine, GEL group, n = 40) or 1-2 units FFP (FFP group, n = 40) in the pump prime. Rapid-thromboelastography (r-TEG) and functional fibrinogen level were measured before skin incision and 15 minutes after heparin reversal. We recorded the volume of chest tube drainage, transfusion requirements and the dosage of pharmacological agents. The ventilation time, ICU length of stay and hospitalization time after surgery were also collected. Results: After heparin neutralization, there were significantly elevated levels of fibrinogen in the FFP group, which were manifested by r-TEG parameters MAf and FLEV. No significant differences were observed between the two groups in postoperative bleeding, transfusion requirements and the usage of pharmacological agents. Recovery time was also comparable between the two groups. Conclusion: In conclusion, prophylactic use of FFP in the priming solution does not provide clinical benefits as presumed. Artificial colloids, such as Gelofusine, can be used safely and effectively as a substitute for FFP in the pump prime. TEG is an effective assessment tool to evaluate postoperative coagulation function in pediatric patients.

Clinical application of pulsatile perfusion during cardiopulmonary bypass in pediatric heart surgery.

The benefits of pulsatile over nonpulsatile perfusion has been widely debated in pediatric cardiac operations with cardiopulmonary bypass (CPB). To evaluate the role of pulsatile perfusion in pediatric complicated patients with congenital heart disease undergoing open heart surgery, we performed pulsatile CPB and compared several effects with nonpulsatile perfusion. Pediatric patients (n = 24) diagnosed as typical tetralogy of Fallot (TOF) were randomly divided into two groups: pulsatile perfusion (PP) group and nonpulsatile perfusion (NP) group. Pulsatile perfusion patients used modified roller pump PP during cross-clamping period in CPB, although NP cases used roller pump continuous flow perfusion during CPB. We monitored hemodynamic status and inflammatory media in blood samples over time in all patients. Effective PP can be monitored in PP patients and pulse pressure (&Dgr;P) was significantly higher in PP group than NP group (p < 0.01). Inflammatory media peaked at the time CPB was weaned off. In PP patients, IL-8 and TNF-α were lower after cross-clamp off and intensive care unit period than in NP cases. Free plasma hemoglobin concentration in PP group at preclamp off and CPB weaned off were higher than that of NP group (p < 0.05). Pulsatile perfusion can be successfully applied in pediatric perfusion. Pulsatile perfusion had the role of reducing concentration of inflammatory media in pediatric patients.

Retrospective analysis of 99 patients with the application of extracorporeal membrane oxygenation in Fuwai Hospital.

The purpose of this study was to retrospectively summarize and analyze the data of 99 cases with the application of consecutive extracorporeal membrane oxygenation (ECMO) from December 2004 to August 2008 in Fuwai Hospital. The intersurface of the ECMO equipment system was completely heparin coated. All patients received venoarterial ECMO, and the activated clotting time was maintained between 120 and 180 seconds. The heparin dose was 5–20 U · kg−1 · h−1. Mean blood flow was 40–220 ml · kg−1 · min−1 during ECMO assisted period. The shortest ECMO time was 12 hours, and the longest was 504 hours (mean time, 119.45 ± 80.20 hours). Sixty patients (60.6%) weaned from ECMO successfully; 54 of them (84%) were discharged, and six died of postoperative complications. Thirty-nine patients could not wean from ECMO. Total discharge rate was 54.5%. ECMO is an effective mechanical assistant therapy for cardiac and pulmonary failure after cardiac surgery. Earlier use of ECMO for heart lung failure patients and avoidance of irreversible damage to the main organs are still the key points in the success of ECMO.