Transfusion-free cardiopulmonary bypass in Jehovah's Witness patients weighing less than 5 kg

Performing cardiac surgery on pediatric Jehovah's Witness patients is a great challenge for the surgical team and especially for the perfusionist. Jehovah's Witnesses reject blood transfusions on the grounds of their literal interpretation of passages of the Bible. In accordance with this belief, Jehovah's Witnesses feel that it is also forbidden to retransfuse autologous blood that has been separated from their own circulatory system. We report the use of cardiopulmonary bypass (CPB) during open-heart surgery in three infants with a body weight of 4.5 kg, 3.5 kg, and 3.1 kg, respectively, without transfusion of blood components. A small-volume CPB circuit with a priming volume of 200 mL, including the arterial line filter, was designed to decrease the degree of hemodilution. A dedicated pediatric heart lung machine console with remote pump heads and intensive blood conservation efforts allowed the operation without the use of donor blood. The CPB circuits were primed with crystalloid solution only. The procedures were performed in normothermia or in moderate hypothermia. Pre-CPB hemoglobin levels were 10.8 g/dL, 10.6 g/dL, and 8.5 g/dL. The hemoglobin concentrations measured during CPB ranged from 5.9 to 6.5 g/dL, 6.4 to 6.8 g/dL, and 5.5 to 5.9 g/dL, respectively. The patients did not receive any blood or blood products during their entire hospital stay.     

6%羟乙基淀粉130/0.4体外循环预充对心脏手术患儿血浆胶体渗透压及乳酸水平的影响

Objective To investigate the effects of hydroxyethyl starch 130/0.4 (HES) used as priming fluid for cardiopulmonary bypass (CPB) on the plasma colloid osmotic pressure (COP) and lactic acid (LAC) concentration in infants undergoing cardiac surgery.Methods Forty infants of either sex with age ≤6 yr undergoing cardiac surgery with CPB were randomly divided into 2 groups (n =20 each): HES group and control group. The left radial artery and the right internal jugular vein were cannulated for blood pressure (BP) and the central venous pressure (CVP) monitoring. Arterial blood gases, blood LAC concentration, hemoglobin (Hb), hematocrit (Hct), mean arterial pressure (MAP) and nasopharyngeal temperature were measured and recorded immediately before and 5 min after aortic cross-clamping, at the end of CPB and operation. Plasma COP was measured before induction of anesthesia (T1), at 5 and 30 min of CPB (T2 and T3, respectively), before routine ultra-filtration (T4), at the end of CPB (T5) and2 h in ICU (T6).Results The plasma LAC concentration was significantly lower and the COP significantly higher in HES group than in control group (P＜0.05 or 0.01).The plasma LAC concentration increased after aortic cross-clamping, reached the peak at the end of CPB and then declined at the end of operation, but was still higher than that before aortic cross-clamping in both groups. Plasma COP was significantly decreased during CPB as compared with the baseline at T1, but increased at T6 in both groups.Conclusion Using HES 130/0.4 as pdming fluid for CPB can effectively improve plasma COP and reduce blood LAC level in infants undergoing cardiac surgery with CPB.     

5kg以下低体重婴儿室间隔缺损的外科治疗

目的报道低体重婴儿室间隔缺损(VSD)伴肺动脉高压的外科手术修补结果和体会.方法1994年3月至1999年12月,对50例2～11月龄,体重3.2～5.0?kg的VSD病婴采用中度低温体外循环行补片修补术.全组术前均伴中度以上肺动脉高压(Pp/Ps平均为0.68±0.09).结果住院死亡2例,住院死亡率为4%,死亡原因分别为心包压塞和脑昏迷.术后主要并发症为肺部感染、肺动脉高压危象和心律失常.结论对5?kg以下低体重婴儿的较大VSD采用外科手术修补可以取得满意效果.     

Surgery for coarctation of the aorta in infants weighing less than 2 kg

BACKGROUND: Low- and very low-birth weight infants are now candidates for reparative cardiac surgery. Outcomes after coarctation repair have not been characterized in this patient population. METHODS: We performed a retrospective review of 18 consecutive neonates less than 2 kg who underwent repair of aortic coarctation between August 1990 and December 1999. RESULTS: Median weight was 1,330 g, and median gestational age was 31 weeks. A ventricular septal defect was present in 5 patients, and Shone's complex in 4. Sixteen patients had resection and end-to-end anastomosis, and 2 had resection and subclavian flap. Median clamp time was 15.5 minutes. One patient died during hospitalization. Two patients died late postoperatively (5-year estimated survival 80%). Mean follow-up was 28.5 months. Eight patients (44%) had a residual or recurrent coarctation, 5 underwent balloon dilation, and 3 underwent reoperation. Freedom from reintervention for recoarctation was 60% at 5 years. Shone's complex or a hypoplastic arch was an independent risk factor for decreased survival (p < 0.001). Very low birth weight was a multivariate predictor for increased risk of recoarctation (p = 0.01). CONCLUSIONS: Coarctation repair in less than 2-kg premature non-Shone's infants can be performed with a low mortality. The rate of recoarctation is higher in the very low-birth weight infants, but can be managed with low risk.     

A review of laparoscopic Nissen fundoplication in children weighing less than 5 kg

Purpose

Minimally invasive procedures in small infants and neonates are being performed in increasing numbers. In this study, we describe our institution's experience with laparoscopic Nissen fundoplications (LNFs) in children weighing less than 5 kg.

Methods

All cases of LNF attempted in children weighing less than 5 kg since January 2003 at a tertiary-care pediatric hospital were reviewed after Institutional Review Board approval.

Results

One hundred twenty-two children weighing less than 5 kg underwent LNF during the study period. They ranged from 2 weeks to 3 years of age (mean, 94 ± 61.3 days) and weighed 1.94 to 4.99 kg (mean, 3.68 ± 0.77 kg). Twenty-nine percent (n = 35) were neurologically impaired. Eighty-eight percent (n = 107) had concurrent gastrostomy tube placement. Eight (7%) were converted to laparotomy. The average operative time was 112 ± 46 minutes. Seventy-one percent (n = 87) required intensive care unit use for an average of 14.3 ± 17.4 days. The average time to start enteral feeds was 2.6 ± 2.6 days. Thirty-one percent (n = 38) required postoperative mechanical ventilation for an average of 12.0 ± 20.6 days. The average hospital length of stay was 36.6 ± 36.0 days (range, 3-175 days).Six patients (5%) had a complication or recurrent gastroesophageal reflux. Three patients had recurrent reflux, one of which underwent another LNF. One patient had a gastric perforation. Another required a redo LNF after a disrupted wrap was noted at a recurrent hiatal hernia repair. Lastly, one patient had bleeding from an accessory hepatic artery with liver retractor placement.

Conclusions

Laparoscopic Nissen fundoplication can safely and effectively be performed in small children (<5 kg) with similar outcomes and rates of complication as previously published reports in larger children. These children, however, do have prolonged intensive care unit and mechanical ventilation use associated with their prematurity and significant comorbidities.     

Repair of complete atrioventricular septal defects in patients weighing less than 5 kg

BACKGROUND: The aim of this study was to evaluate the impact of weight less than 5 kg at operation on mortality and morbidity in patients with atrioventricular septal defect (AVSDc) undergoing total correction. METHODS: Between January 1990 and December 2002, 190 consecutive patients with AVSDc underwent total biventricular correction. They were divided into two groups: group I (n = 64 patients weighing < 5 kg) and group II (n = 126 patients weighing > 5 kg). Associated major cardiac malformations were found in 49 (25.8%) patients. Associated left atrioventricular valve (LAVV) malformations were found in 35 (18.4%) patients. The mean follow-up time was 4.1 +/- 2.9 years (range 2 months-10.7 years). RESULTS: The in-hospital mortality in group I was 7.8% (5 patients) versus 8.7% (11 patients) in group II (p = 0.95). Major associated cardiac malformations (p < 0.001) and pulmonary hypertension (p = 0.006) were found to be strong predictors for poor postoperative survival. At discharge the mean LAVVR grade in group I was 1.45 +/- 1.2 versus 1.2 +/- 1 in group II (p = 0.13). The actuarial overall survival rates at 1, 3, 5, and 7 years were 96.5%, 92.5%, 91.5%, and 89% respectively and the actuarial overall reoperation free survival rates at 1, 3, 5, and 7 years were 95%, 87%, 84%, and 73%. Twenty-three patients underwent reoperation due to severe left atrioventricular valve regurgitation (LAVVR). Strong predictors for overall reoperation free survival were the operation year before 1995 (p < 0.001), postoperative LAVVR greater than or equal to 2 (p = 0.006), major associated cardiac malformations (p = 0.00034), associated LAVV malformations (p = 0.0044), and non or partial LAVV cleft closure (p = 0.012). The actuarial survival rates between patients weighing less than 5 kg versus patients weighing more than 5 kg were similar (p = 0.51); instead the overall reoperation free survival was significantly lower in patients weighing less than 5 kg (p = 0.022) according to the log-rank test. Weight less than 5 kg (p = 0.023, beta = -0.6) was one of the predictors for reoperation due to severe LAVVR in this series. CONCLUSIONS: We may conclude that in the current era repair of AVSDc can be carried out successfully in patients less than 5 kg, however, weight less than 5 kg at initial complete repair seems to be a predictor for late reoperation due to LAVVR. Suture separation at the cleft site or between the leaflets of the newly created mitral valve and the patch remain the main causes of postoperative LAVVR in patients weighing less than 5 kg.     

High-flow total body perfusion with severe hemodilution and normothermia in infants weighing less than 10 kg—Safe limits of hemodilution in cardiopulmonary bypass in infants

Cardiopulmonary bypass with 17 to 57 per cent dilution of hemoglobin for repair of ventricular septal defect (VSD) was applied to 26 infants weighing less than 10 kg at normal temperature. The higher flow rate was required to compensate the reduced oxygen carrying capacity and to maintain an adequate arterial pressure in proportion to a decrease of hemoglobin value. Perfusion index resulted in 3.0 to 6.5 L/m²/min in this series. When the dilution ratio of hemoglobin became more than 50 per cent and high flow rate was required, however, oxygen transfer ratio decreased remarkably on account of inadequate oxygen delivery and impaired venous return. In these cases, it was difficult to remove the diluent immediately after the operation in spite of powerful diuretic therapy. The results of the present study indicate that the safe limits of hemodilution is 50 per cent in cardiopulmonary bypass at normal temperature in infants.     

Perioperative blood product transfusion of two different perfusion strategies on pediatric patients undergoing aortic arch surgery

Simple regional cerebral perfusion (SRCP) or cerebro-myocardial perfusion (CMP) is selectively used in one-stage complex aortic arch malformation repair. This analysis was performed to investigate the effect of CMP and SRCP on perioperative blood product consumption, and to evaluate whether these two strategies have different effects on the clinical outcomes. A retrospective analysis of 284 children with complicated aortic malformation from January 2010 to June 2018 was performed. The overall cohort was divided into SRCP group (n = 202) and CMP group (n = 82). A comprehensive comparison of perioperative blood product consumption-related indexes was performed. Cardiopulmonary bypass time, cardiac arrest time, cooling, and rewarming time in the CMP group were significantly shorter than those in the SRCP group (P < .05). Chest tube time was 3.82 ± 1.33 days in the SRCP group compared to 3.42 ± 0.97 days in the CMP group (P = .005). Moreover, intraoperative platelet (PLT) transfusion volume (mL/kg) and rate (%) were significantly lower in the CMP group (P < .001). Multivariate regression analysis found that intraoperative PLT transfusion was significantly negatively correlated with CMP management [OR = 0.237 (0.110-0.507), P < .001] and CPB time was independently associated with delayed chest tube removal (>3 days) [OR = 1.010 (1.001-1.020), P = .031]. In-hospital mortality and early postoperative adverse events were not significantly different between the two groups. In children with on-pump complex aortic arch surgeries, CMP is more preferable than SRCP in blood protection. However, overall prognosis was not remarkably different between these two perfusion groups. They are both safe and feasible.     

Effect of decreased plasma colloid osmotic pressure on development of pulmonary edema in dogs

The effect of decreased plasma colloid osmotic pressure on the development of pulmonary edema was studied in anesthetized dogs. Lung lymph flow was used as a sensitive and reliable indicator of fluid filtration rate in the lung. When plasma colloid osmotic pressure alone was reduced by slow infusion of saline, and hydrostatic pressure in the pulmonary vascular bed was maintained at normal level by exsanguination, lung lymph flow increased almost linearly with the reduction in colloid osmotic pressure, but was not increased more than five fold of the control, despite a reduction of 80% in the plasma colloid osmotic pressure. Furthermore, there was no evidence of fluid in the tracheal aspirations and no gross evidence of pulmonary edema. In contrast, both decrease in colloid osmotic pressure and increase in pulmonary capillary hydrostatic pressure produced a marked increase in lung lymph flow. This flow varied linearly with the level of the pulmonary artery wedge-plasma colloid osmotic pressure difference and approached twelve fold of the control, when the plasma colloid osmotic pressure was reduced by 73% and the pulmonary artery wedge pressure was elevated by 20 mmHg from the baseline. Our data indicate that decreased colloid osmotic pressure is not associated with the development of pulmonary edema, when there is no increase in pulmonary vascular hydrostatic pressure.     

兔体外循环中聚乙二醇牛血红蛋白偶联物对平均动脉压、胶体渗透压及p50的影响

目的探讨在体外循环(CPB)预充液中加入聚乙二醇牛血红蛋白偶联物(PEG-bHb)对兔平均动脉压(MAP)、胶体渗透压(COP)及p50的影响。方法24只成年健康大耳白兔(2．59±0．19)kg,通过股动脉、颈静脉插管建立体外循环通路,转流1h。随机分成3组,对照组(n =8),以晶／胶体液作为体外循环预充液；实验组1(n=8),在预充液中加入PEG-bHb,PEG-bHb占总容量(兔循环血量+预充量)的5％；实验组2(n=8),预充液中加入PEG-bHb,占总容量(兔循环血量+预充量)的15％,体外循环开始后放出自体血(放血量占兔循环血量的20％),CPB结束后将自体血回输。每组监测CPB前和CPB中平均动脉压；在CPB前、CPB中15、50 min、CPB后1 h测胶体渗透压及动脉血p50值。结果实验组1和实验组2在CPB中的MAP均高于对照组,但只有实验组2在转中10 min时与对照组相比差异有统计学意义(P＜0．05)；实验组2在CPB中COP值均较高；实验组1动脉血p50值较对照组高。结论PEG-bHb占实验兔循环血量+预充量的5％对CPB中和CPB后MAP和COP无明显影响,并且由p50提示向组织释放O_2量增多,此量可安全用于CPB预充；另外,在CPB前放出部分自体血将对CPB中血液保护发挥一定作用。     

舒芬太尼用于不同心脏手术患者的药代动力学

目的 研究舒芬太尼用于不同心脏手术患者的药代动力学特征.方法 择期心脏手术患者16例,年龄56～64岁,体重52 ～ 78 kg,ASA分级Ⅱ或Ⅲ级,按手术类型分为非CPB下冠状动脉旁路移植术组(Ⅰ组)和心脏瓣膜置换术组(Ⅱ组),每组8例.麻醉诱导时前臂静脉注射舒芬太尼5μg/kg,于注药后1、3、5、10、20、30、60、120、180、240和360 min时采集桡动脉血样3ml,抗凝,用液相色谱-质谱法测定血浆舒芬太尼浓度,3P97药理学程序计算CPB前和CPB时的药代动力学参数.结果 舒芬太尼在心脏手术患者的药代动力学符合三室模型,其三指数函数方程Ⅰ组为:Cp(t)＝11.7e -0.47t+1.9 e-0.043t+ 0.27 e-0.0032t；Ⅱ组CPB前和CPB时分别为:Cp(t) ＝33.4 e-1.87t+7.1 e-0.103t+2.0e 0.0248t和Cp(t) ＝23.8 e-0.54t+5.2 e-0.054t+0.15 e-0.0017t.与Ⅰ组比较,Ⅱ组CPB前常数和速率常数(P、A、B、π、α、β、K21、K13、K31、K10)、消除半衰期、药物浓度-时间曲线下面积升高,快速分布半衰期、表观分布容积降低,CPB时P、A、β、消除半衰期、k21、K10和药物浓度-时间曲线下面积升高,B、β、k31、表观分布容积和清除率降低(P< 0.05或0.01).结论 舒芬太尼在心脏手术患者的药代动力学特征符合三室模型,心功能差和低温CPB导致药物代谢减慢,作用时间延长.     

Comparison of parameters for detection of splanchnic hypoxia in children undergoing cardiopulmonary bypass with pulsatile versus nonpulsatile normothermia or hypothermia during congenital heart surgeries

The aim of this study is to evaluate gastric mucosal oxygenation together with whole-body oxygen changes in infants undergoing congenital heart surgery with cardiopulmonary bypass (CPB) procedure and the use of either pulsatile or nonpulsatile mode of perfusion with normothermia and pulsatile or nonpulsatile moderate hypothermia. Sixty infants undergoing congenital cardiac surgery were randomized into four groups as: nonpulsatile normothermia CPB (NNCPB, n = 15), pulsatile normothermia CPB (PNCPB, n = 15), nonpulsatile moderate hypothermia CPB (NHCPB, n = 15), and pulsatile moderate hypothermia CPB (PHCPB, n = 15) groups. In NNCPB and PNCPB groups, mild hypothermia was used (35°C), whereas in NHCPB and PHCPB groups, moderate hypothermia (28°C) was used. Gastric intramucosal pH (pHi), whole-body oxygen delivery (DO(2)) and consumption (VO(2)), and whole-body oxygen extraction fraction were measured at sequential time points intraoperatively and up to 2 h postoperatively. The measurement of continuous tonometry data was collected at desired intervals. The values of DO(2), VO(2), and whole-body oxygen extraction fraction were not different between groups before CPB and during CPB, whereas the PNCPB group showed higher values of DO(2), VO(2), and whole-body oxygen extraction fraction compared to the other groups at the measurement levels of 20 and 60 min after aortic cross clamp, end of CPB, and 2 h after CPB (P < 0.0001). Between groups, no difference was observed for pHi, lactate, and cardiac index values (P > 0.05). This study shows that the use of normothermic pulsatile perfusion (35°C) provides better gastric mucosal oxygenation as compared to other perfusion strategies in neonates and infants undergoing congenital heart surgery with CPB procedures.     

6%羟乙基淀粉对冠状动脉旁路移植术血浆胶体渗透压的影响

目的观察6%羟乙基淀粉130/0.4对非体外循环冠状动脉旁路移植术（OPCAB）中血浆胶体渗透压（COP）的影响。方法 34例行OPCAB患者（NYHAⅠ或Ⅱ级）,麻醉诱导时开始输注6%羟乙基淀粉至血管吻合完毕,总量控制为25～35ml/kg。分别于输注前（T0）、离断乳内动脉后（T1）、桥血管吻合完毕时（T2）监测血浆COP及血流动力学变化,并记录输液量、失血量、Hb、Hct及心脏指数（CI）。结果手术过程血流动力学稳定。T1时失血量（120±30）ml,输注6%羟乙基淀粉（998±110）ml,血浆COP由T0时（21.7±1.4）mmHg升高至（22.3±1.3）mmHg（P〈0.05）;T2时失血量（778±179）ml,输注6%羟乙基淀粉（2190±135）ml,血浆COP降至（21.5±1.4）mmHg。T2时Hb和Hct较T0时明显下降（P〈0.01）,但CI显著升高（P〈0.05）。结论 6%羟乙基淀粉可稳定OPCAB术血浆COP。     

Nitric oxide added to the sweep gas of the oxygenator during cardiopulmonary bypass in infants: A pilot randomized controlled trial

Our objective was to assess the effect of nitric oxide added to the sweep gas of the oxygenator during cardiopulmonary bypass (CPB) in infants on platelet count, platelet function, clinical outcomes, and safety. A randomized, double‐blinded, placebo‐controlled clinical trial in infants less than a year of age undergoing cardiac surgery requiring CPB was undertaken. Nitric oxide at a dose of 20 ppm was added to the sweep gas in the treatment group. Blood was collected at baseline and prior to separation from CPB to measure platelet count and function as determined by responsiveness to specific agonists. Clinical outcomes were observed through hospital discharge. Methemoglobin levels were measured preoperatively, at the conclusion of CPB, and upon admission to the ICU. Forty patients consented and were randomized in the trial. Eighteen patients were randomized to the treatment group and 22 were included in the placebo group. The groups were similar in terms of age, weight, gender, and surgical complexity. No significant differences were found in measures of platelet count, platelet response to agonist, or clinical outcomes. Patients in the treatment group had higher methemoglobin levels after receiving nitric oxide, but no levels approached toxicity (maximum 2.4%). Nitric oxide added to the sweep gas of the oxygenator during CPB in infants did not have an appreciable effect on the preservation of platelet count, platelet responsiveness to agonist, or clinical outcomes. Methemoglobin levels were increased after receiving nitric oxide but were far below a toxic level of 15%.     

Outcome of tunnelled central venous catheters used for haemodialysis in children weighing less than 15 kg

Purpose

Central venous catheters (CVC) are frequently used for haemodialysis (HD) in children. However, there is paucity of information on the outcomes of CVCs when used for HD in very young patients. Our objective is to report the success, safety and complication rates of CVCs used for HD in children weighing less than 15 kg.

Materials and methods

This is a single-center retrospective study of all patients with end-stage renal disease (ESRD) weighing < 15kg, who underwent a tunneled CVC placement for HD, between July 2006 and June 2012 at our institution. Analysed data included clinical background, age and weight at initiation of HD, outcome of HD, CVC vein insertion site, reason for removal, and catheter survival (in days).

Results

Thirty-one CVC were placed in 11 patients weighing < 15 kg, 8 males and 3 females. The main causes of ESRD were renal dysplasia and congenital nephrotic syndrome. At the beginning of HD, mean age was 27.5 (range 5–60) months and mean weight was 10.4 kg (4.5–13 kg). The preferred insertion site was the right internal jugular vein (90%). Mean duration of HD was 312 days. Mechanical factors were the main reason for catheter removal (39%). Mean catheter survival was 110 days/catheter.

Conclusions

We believe our study provides relevant information and encouraging data to support the use of CVC for HD in this cohort of infants; however, further improvement in prevention of catheter thrombosis and management of infections needs to be achieved.     

Validation of a definition of excessive postoperative bleeding in infants undergoing cardiac surgery with cardiopulmonary bypass

Objective

To derive and validate an objective definition of postoperative bleeding in neonates and infants undergoing cardiac surgery with cardiopulmonary bypass.