Prospective randomized controlled trial of acute normovolaemic haemodilution in major gastrointestinal surgery

Background. The efficacy of acute normovolaemic haemodilution(ANH) remains uncertain because of a lack of well-designed prospectiverandomized controlled trials. The aim of this study was to assessthe effects of ANH on allogeneic transfusion, postoperativecomplications, and duration of stay. Methods. Consecutive patients undergoing major gastrointestinalsurgery were randomized to a planned 3-unit ANH, or no ANH.Both groups underwent identical management including adherenceto a transfusion protocol after surgery. Outcome measures includedthe number of patients receiving allogeneic blood, complications,and duration of stay. Results. 380 patients were screened of which 160 were includedin the study, median age was 62 yr (range 23–90), ‘ANH’n=78, ‘no ANH’ n=82. There was no significant differencebetween groups in the number of patients receiving allogeneicblood 22/78 (28%) vs 25/82 (30%), the total number of allogeneicunits transfused (90 vs 93), complication rate, or durationof stay. Haemodilution significantly increased anaesthetic time,median 55 (range 15–90) vs 40 min (range 17–80)(P<0.001). Significantly fewer patients in the ANH groupexperienced oliguria in the immediate postoperative period 37/78(47%) vs 55/82 (67%) (P=0.012). The most significant factorsaffecting transfusion were blood loss, starting haemoglobin,and age. When compared with ASA-matched historical controls,the introduction of a transfusion protocol reduced the transfusionrate in colorectal patients from 136/333 (41%) to 37/138 (27%),P=0.004. Conclusions. In this large pragmatic study, ANH did not affectallogeneic transfusion rate in major gastrointestinal surgery.Preoperative haemoglobin, blood loss, and transfusion protocolare the key factors influencing allogeneic transfusion.     

Isolated reduction of haematocrit does not compromise in vitro blood coagulation

Low haematocrit values are generally well tolerated in termsof oxygen transport but a low haematocrit might interfere withblood coagulation. We thus sampled 60 ml of blood in 30 healthyvolunteers. The blood was centrifuged for 30 min at 2000 g andseparated into plasma, which contained the platelet fraction,and packed red blood cells. The blood was subsequently reconstitutedby combining the entire plasma fraction with a mixture of packedred blood cells, 0.9% saline, so that the final haematocritwas either 40, 30, 20, or 10%. Blood coagulation was assessedby computerized Thrombelastograph^® analysis. Data were comparedusing repeated measures analysis of variance and post-hoc pairedt-tests with Bonferroni correction. Decreasing the haematocritfrom 40 to 10% resulted in a shortening of reaction time (r)and coagulation time (k), and an increase in angle     

Cerebral effects and blood sparing efficiency of sodium nitroprusside-induced hypotension alone and in combination with acute normovolaemic haemodilution

The combined reduction of oxygen-carrying capacity and perfusionpressure during the combination of acute normovolaemic haemodilution(ANH) and controlled hypotension (CH) raises concerns of hypoperfusionand ischaemic injury to the brain. Forty-two patients undergoingradical prostatectomy were prospectively allocated to receiveCH induced by sodium nitroprusside (mean arterial pressure (MAP)50 mm Hg), a combination of CH+ANH (post-ANH haematocrit 29%;intraoperative MAP 50 mm Hg), or standard anaesthesia (control).Serum levels of the brain-originated proteins neuron-specificenolase (NSE) and protein S-100, blood loss, transfusion requirements,adverse effects, and postoperative recovery profile were comparedamong the three groups. Intraoperative blood loss in the CHgroup (mean (SD)) (788 (193) ml) and CH+ANH group (861 (184)ml) was significantly less than in the control group (1335 (460)ml). Significantly fewer total units of allogeneic packed redblood cells (PRBC) were transfused in the patients receivinghypotensive anaesthesia (CH, 3 units; CH+ANH, 2 units; control,17 units). There was no difference in immediate postoperativerecovery profile among the three groups as determined by theemergence from anaesthesia and time to discharge from the postanaesthesiacare unit. Serum S-100 protein concentrations increased significantlyin all groups from baseline to peak concentrations 2 h postoperatively(CH 0.25 (0.11) µg litre^–1; CH+ANH 0.31 (0.12) µglitre^–1; control 0.31 (0.10) µg litre^–1).A return to baseline values was seen within 24 h postoperativelyin all patients. No changes in NSE concentrations were seen.Our observations suggest that CH and CH+ANH were effective inreducing blood loss and transfusion requirements in patientsundergoing radical prostatectomy. Increased serum S-100 proteinconcentrations imply a disturbance in astroglial cell membraneintegrity and an increased endothelial permeability of the blood–brainbarrier. There were no associations between serum S-100 proteinor NSE and adverse cognitive effects. Further work needs tobe done to determine the prognostic importance of S-100 proteinand NSE as surrogate variables of postoperative cerebral complications. Br J Anaesth 2001; 87: 699–705     

Plasma substitution effects of a new hydroxyethyl starch HES 130/0.4 compared with HES 200/0.5 during and after extended acute normovolaemic haemodilution

Background. The volume expansion effect of a recently introducedhydroxyethyl starch, HES 130/0.4, was compared with the commonlyused HES 200/0.5 after rapid infusion of a single large dose(up to 2 litres) administered during acute normovolaemic haemodilution(ANH). Methods. This prospective, randomized, double-blind study included40 patients scheduled for major abdominal surgery with no contraindicationto ANH. Patients were randomized to undergo ANH with eitherHES 130/0.4 (n=20) or HES 200/0.5 (n=20). Blood was collectedto reach a target haemoglobin level of about 8.0 g dl^–1and simultaneously replaced by the same volume of colloid (HES130: 1825 [SD 245] ml; HES 200: 1925 [183] ml). Heart rate,mean arterial pressure, cardiac filling pressure, and cardiacoutput were measured before induction of anaesthesia (baseline),10 min after completion of ANH, before surgery, at the end ofsurgery and on the following morning (postoperative day 1; POD1).ANH blood was systematically retransfused during surgery orbefore POD1. Results. Exchange of about 40% of blood volume resulted in similarhaemodynamic changes in both groups. Filling pressures increasedsignificantly, while cardiac index remained unchanged (HES 130:from 3.3 [0.4] to 3.2 [0.7] litre min^–1 m^–2; HES200: from 3.0 [0.6] to 3.1 [0.7] litre min^–1 m^–2).Need for crystalloids and colloids was similar between the groupsduring surgery and on POD1. Total blood loss (HES 130: median2165 ml, range 660–2970 ml; HES 200: median 2464 ml, range640–19 380 ml) and amount of allogeneic red blood cellstransfused (HES 130: median 0, range 0–4 units; HES 200:median 0, range 0–18 units) were comparable in the twogroups. Conclusions. This study demonstrates a good immediate and medium-termplasma volume substitution effect of HES 130 compared with HES200. HES 130 could represent a suitable synthetic colloid forplasma volume substitution during extensive ANH. Br J Anaesth 2003; 91: 196–202     

Hydroxyethyl starch is superior to lactated Ringer as a replacement fluid in a pig model of acute normovolaemic haemodilution

Background. Tissue tolerance to oxygen privation during acutenormovolaemic haemodilution with different fluids remains unclear.We tested the hypothesis that hydroxyethyl starch (HES) is superiorto lactated Ringer's solution in pigs for preserving tissueperfusion during acute normovolaemic haemodilution. Methods. Twenty-four animals were randomized into control, lactatedRinger's solution and HES groups. All groups, except the control,underwent acute normovolaemic haemodilution. Haemodynamics,oxygen parameter indices, global anaerobic metabolic markers,echocardiographic parameters, gastric tonometry and serum osmolaritywere monitored at baseline, immediately after (0 min) and 60and 120 min after the end of haemodilution. Myocardial, liver,stomach and intestine samples were collected for further evaluation. Results. Cardiac and oxygen parameter index responses to acutenormovolaemic haemodilution were comparable. However, the incrementin cardiac index, stroke volume index, and left ventricularstroke work index were more sustained in the starch group. Inthe lactated Ringer's group, gastric pH decreased significantlyand was accompanied by a significant increase in lactate. Myocardialultrastructure was better preserved in the starch group. Theother tissue samples presented no change. Conclusions. In this model of ANH, the starch group had a superiorhaemodynamic response. Minor loss of myocardial cellular integrityand preserved gastric pHi reinforce these findings.     

Venous oxygen saturation during normovolaemic haemodilution in the pig

BACKGROUND: Hypovolaemia may be considered to represent a volume-restricted cardiac output (CO), but CO varies inversely with the haemoglobin concentration (Hb) and a maximal mixed venous oxygen saturation (SvO2) may be a better target for volume administration than a maximal CO. METHODS: In 10 anaesthetized pigs, volume loading with 6% hydroxyethyl starch was performed to obtain a maximal SvO2 followed by normovolaemic haemodilution with 6% hydroxyethyl starch. RESULTS: Volume loading increased SvO2 from 55.0+/-5.2% to 64.8+/-9.0% (mean+/-SD) associated with an increase in CO (2.3+/-0.4 to 3.5+/-0.9 l/min) and central venous oxygen saturation (ScvO2; 68.2+/-9.3% to 79.4+/-7.2%; P<0.05). Heart rate (HR), mean arterial (MAP), central venous (CVP), pulmonary arterial mean (PAMP), and occlusion pressures (PAOP) increased as well (P<0.05). In contrast, during progressive haemodilution, SvO2 and ScvO2 remained statistically unchanged until the haemoglobin concentration had decreased from 5.5+/-0.4 to 2.9+/-0.2 mM, while CO and HR increased at a haemoglobin value of 4.4+/-0.4 and 4.0+/-0.4 mM and CVP and PAOP decreased at a haemoglobin of 4.0+/-0.4 and 2.9+/-0.2 mM, respectively (P<0.05) leaving MAP unaffected. CONCLUSION: This study found that volume loading increased cardiac output and mixed and central venous oxygen saturations in parallel, but during normovolaemic haemodilution an increase in cardiac output left mixed and central venous oxygen saturations statistically unchanged until haemoglobin concentration was reduced by approximately 50%. Accordingly, volume therapy should be directed to maintain a high venous oxygen saturation rather than a change in cardiac output.     

Transfusion guidelines in children: I

The transfusion of a blood product to a child is associated with a greater risk of harm when compared to an adult. Transfusion is necessary in certain situations and so the benefits have to be balanced against potential adverse events. This article will present information concerning blood transfusion thresholds in children, calculations for maximal tolerated blood loss and the concept of massive transfusion protocols.     

Transfusion guidelines in children: I

The transfusion of a blood product to a child is associated with a greater risk of harm when compared to an adult. Transfusion is necessary in certain situations and so the benefits have to be balanced against potential adverse events. This article will present information concerning blood transfusion thresholds in children, calculations for maximal tolerated blood loss and the concept of massive transfusion protocols.     

Transfusion guidelines in children: I

The transfusion of a blood product to a child is associated with a greater risk of harm when compared to an adult. In certain situations transfusion is necessary and so the benefits have to be balanced against potential adverse risks. This article will present information concerning blood transfusion thresholds in children, calculations for maximal tolerated blood loss and the concept of massive transfusion protocols.     

回收式自体输血在儿童先天性髋关节脱位手术中的应用

[目的]探讨儿童先天性髋关节脱位的股骨和骨盆联合手术中洗涤式自体血液回收的应用方法与前景。[方法]2003年8月~2005年12月,17例先天性髋关节脱位股骨和骨盆联合手术中,使用Cell Saver 5血液回收系统行术中的血液回收。观察回输自体血液后的并发症发生情况,记录术中估计失血量、实际回收血量,以及回输血前后的Hb、Hct、P lt、PT、APTT、HR、BP、SPO2等的变化情况。[结果]17例患儿术中血液回收总量2 090 m l,平均每人(171±53)m l。其中4例出现一过性血红蛋白尿,其他无并发症。患者术前和术后24 h的Hb、Hct、HR比较差异有显著性意义(P<0.01);患者术前和术后24 h的P lt、PT、APTT、SPO2、BP比较差异无显著性意义(P>0.05)。[结论]儿童先天性髋关节脱位的股骨和骨盆联合手术中的血液回收是安全、有效的自体输血方式,明显节约异体血的用量,有效避免血液传播性疾病的发生。     

Blood loss and the need for transfusion in patients who undergo partial or radical nephrectomy for renal cell carcinoma

PURPOSE: We assessed blood loss and subsequent transfusion associated with nephrectomy performed for suspected renal cell carcinoma to establish guidelines for preoperative autologous blood donation and identify a subgroup of patients that may benefit from erythropoietin administration. MATERIALS AND METHODS: We retrospectively reviewed the charts of 211 patients who underwent partial (73%) or radical (23%) nephrectomy for presumed renal cell carcinoma at our institution between 1990 and 1999. Patients were divided into groups 1-44.5% treated with radical nephrectomy for localized disease, 2-21.3% radical nephrectomy for metastatic lesions invading the renal vasculature or inferior vena cava, 3-8% radical nephrectomy for metastatic disease with locally extensive lesions and 4-26.5% partial nephrectomy for localized lesions. Patient charts were evaluated for preoperative and postoperative hematocrit, estimated blood loss, transfusions received, surgical complications and underlying disease. RESULTS: Median estimated blood loss was 200, 400, 250 and 555 cc in groups 1 to 4, respectively. However, patients in groups 2 and 3 had a substantially greater range of blood loss than those in groups 1 and 4, respectively. The incidence of those with a blood loss of greater than 1 l. was 7%, 36%, 24% and 11% in groups 1, to 4, respectively. The incidence of those requiring transfusion was significantly lower in group 1 than in groups 2 to 4 (18% versus 44%, 24% and 30%, respectively, p <0.009). Mean transfusion requirement plus or minus standard deviation was significantly greater in groups 2 and 3 than in 1 and 4 (2.3 +/- 1.08, 5.5 +/- 4.4, 11.3 +/- 9.6 and 2.3 +/- 1.7 units, respectively, p <0.05). No significant difference was noted in the change in hematocrit as a result of surgery in the 4 groups (p >0.05). Similarly underlying disease and operative complications did not have a significant effect on blood loss or transfusion (p >0. 05). CONCLUSIONS: Radical or partial nephrectomy for localized renal cell carcinoma leads to consistent and well tolerated operative blood loss that rarely results in the need for substantial transfusion. In contrast, nephrectomy for advanced disease may cause a risk of greater blood loss and subsequent need for the transfusion of multiple units of blood. While preoperative autologous blood donation may have limited value in this regard due to the high cost and number of units needed, preoperative erythropoietin administration may be a viable option. Prospective randomized studies are currently planned.     

Assessment of intraoperative blood transfusion practice during elective non-cardiac surgery in an Indian tertiary care hospital

Background. We assessed appropriate intraoperative use of wholeblood during elective surgery. Methods. This prospective observational audit by a team of anaesthetistsover 3 months in a multi-speciality tertiary care teaching hospitalused strict preset criteria to evaluate the use of blood transfusionduring elective surgery by anaesthetists. The criteria usedto evaluate the rate of appropriate transfusion were haemoglobinless than 8 g dl^–1, haemoglobin less than 10 g dl^–1in patients with medical co-morbidities and blood loss greaterthan 20% of blood volume when more than 1000 ml. Results. The overall rate of appropriate use of blood was 40.7%;it was inappropriate in 19.2% of cases (haemoglobin >11 gdl^–1). The primary trigger was low haemoglobin (measuredintraoperatively or derived from blood loss). Patients in whomhaemoglobin was measured intraoperatively had a significantlyhigher appropriate use of blood (P<0.05). There was a reductionin blood use over the 3-month audit period (P<0.05). Conclusions. Current intraoperative blood use is sub-optimal.Intraoperative haemoglobin estimation is an effective and simplemeasurement to improve appropriate use of blood. The indicationfor transfusion should be recorded in the case notes. Br J Anaesth 2003; 91: 586–9     

Storage of strain-specific rat blood limits cerebral tissue oxygen delivery during acute fluid resuscitation

BACKGROUND: The effect of blood storage on tissue oxygen delivery has not been clearly defined. Some studies demonstrate reduced microvascular oxygen delivery, whereas others do not. We hypothesize that storage of rat blood will limit its ability to deliver oxygen to cerebral tissue. METHODS: Anaesthetized rats underwent haemorrhage (18 ml kg(-1)) and resuscitation with an equivalent amount of fresh or 7 day stored strain-specific whole blood. Arterial blood gases, co-oximetry, red cell counts and indices, and blood smears were performed. Hippocampal tissue oxygen tension (PBr(O2)), regional cerebral blood flow (rCBF), and mean arterial pressure (MAP) were measured before and for 60 min after resuscitation (n=6). Data [mean (SD)] were analysed by anova. RESULTS: After 7 days, there was a significant reduction in pH, Pa(O2), an increase in Pa(CO2), but no detectable plasma haemoglobin in stored rat blood. Stored red blood cell morphology demonstrated marked echinocytosis, but no haemolysis in vitro. MAP and PBr(O2) in both groups decreased after haemorrhage. Resuscitation with stored blood returned MAP [92 (SD 16) mm Hg] and PBr(O2) [3.2 (0.7) kPa] to baseline, whereas rCBF remained stable [1.2 (0.1)]. Resuscitation with fresh blood returned MAP to baseline [105 (16) mm Hg] whereas both PBr(O2) [5.6 (1.5) kPa] and rCBF [1.9 (0.4)] increased significantly (P<0.05 for both, relative to baseline and stored blood group). There was no evidence of haemolysis in vivo. CONCLUSIONS: Although resuscitation with stored blood restored cerebral oxygen delivery to baseline, fresh blood produced a greater increase in both PBr(O2) and rCBF. These data support the hypothesis that storage limits the ability of RBC to deliver oxygen to brain tissue.     

Erythropoietin therapy and preoperative autologous blood donation in children undergoing open heart surgery

We assessed the feasibility and efficacy of subcutaneous erythropoietinalpha (EPO) therapy and preoperative autologous blood donation(ABD) in children undergoing open heart surgery. Thirty-ninechildren were treated consecutively with EPO (100 U kg^–1s.c. three times a week in the 3 weeks preceding the operationand i.v. on the day of surgery) and two ABDs were made (Group 1).As controls to compare transfusion requirements, 39 consecutiveage-matched patients who had undergone open heart surgery duringthe two preceding years were selected (Group 2). In a meantime of 20 (SD 5) days, 96% of scheduled ABDs were performedand only three mild vasovagal reactions were observed. The meanvolume of autologous red blood cells (RBC) collected was 6 (1) ml kg^–1and the mean volume of autologous RBC produced as a result ofEPO therapy before surgery was 7 (3) ml kg^–1,corresponding to a 28 (11)% increase in circulating RBC volume.The mean volume of autologous RBC collected was not differentfrom that produced [6 (1) vs 7 (3) ml kg^–1,P=0.4]. Allogenic blood was administered to three out of 39children in Group 1 (7.7%) and to 24 out of 39 (61.5%) in Group2. Treatment with subcutaneous EPO increases the amount of autologousblood that can be collected and minimizes allogenic blood exposurein children undergoing open heart surgery. Br J Anaesth 2001; 87: 429–34     

Autologous blood patch for persistent air leak in children

Purpose

Persistent air leak (PAL) is associated with increased morbidity. Standard treatment of PAL includes chemical or mechanical pleurodesis. Long-term impact of these interventions is not known in the pediatric population. Autologous blood patch (ABP) offers a novel treatment option. We report our experience with autologous blood patch to successfully treat PAL in eight children.

Methods

Children with PAL were treated with ABP. A fresh whole blood sample was obtained from each patient and injected via their pre-existing chest tube. Volume of blood injected, time to cessation of air leak, time to chest tube removal, outcomes and complications were reviewed.

Results

Eight children aged 2 months to 18 years underwent ABP. Three children had immediate seal of air leak, while two patients sealed after 1 and 2 days. Three patients required a second ABP, after which they had immediate seal of air leak. Chest tubes were removed within 2–3 days in 7 cases. One child developed an asymptomatic pneumothorax and required 8 days for radiographic resolution.

Conclusion

ABP appears to be a safe and effective treatment option for PAL in children. ABP offers an inexpensive, easy to perform technique and avoids use of toxic chemicals for pleurodesis in pediatric patients.     

Perioperative course of FXIII in children undergoing major surgery

Background: Acquired deficiency of FXIII because of perioperative hemodilution has been described several times in adults; however, data in children are scarce. We performed a prospective observational trial to evaluate the intraoperative course of FXIII in children undergoing elective major surgery. Methods: Blood samples were repeatedly taken from 46 children aged 0.3–16 years undergoing major surgery. Concentrations of FXIII and fibrinogen, thrombelastometry by ROTEM^®, and cell count were assessed intraoperatively. Results: A significant decrease in FXIII concentration (median 60%; IQR 49–69%) was already noted at beginning of surgical procedures, while most ROTEM^® traces remain unchanged. FXIII levels further deteriorated intraoperatively to minimal levels of 33% (15–61%). Lowest intraoperative clot strength (ExTEM) was 44 mm (34–50 mm), and fibrinogen plasma levels decreased to minimal levels of 130 mg·dl^?1 (95–160 mg·dl^?1). In 43 of 46 children, transfusion therapy was necessary. Despite of transfusion of fresh frozen plasma (cumulative total dose 22 ml·kg^?1 [11–32 ml·kg^?1]) in 21 of 46 children, FXIII level remains low in all children till the end of surgery at levels of 39% (20–46%). Conclusions: Coagulation factor XIII decreased early during major surgery owing to hemodilution. Overall intraoperative FXIII levels remain low despite of transfusion of fresh frozen plasma.     

储血器放置不同高度对术中自体回收红细胞溶血损伤的影响

目的探讨储血器放置不同高度对脊柱手术患者自体回收红细胞溶血损伤的影响。方法选择拟在全麻下行脊柱手术的择期患者90例,男47例,女43例,年龄33～65岁,体重53～82 kg,ASAⅠ或Ⅱ级,术中均使用自体血液回收机行血液回收。采用随机数字表法随机分为三组:进血口高置组(H组)、进血口正常组(N组)和进血口低置组(L组),每组30例。H组:储血器进血口高于手术野水平30 cm;N组:储血器进血口与手术野同一水平;L组:储血器进血口低于手术野水平30 cm。手术结束前,对储血器内回收的血液进行离心、洗涤,抽取洗涤后的血样,行红细胞渗透脆性实验,计算在不同浓度的低渗NaCl溶液中红细胞的溶血率;分别于洗涤血样静置即刻(T_0)、1 h(T_1)和2 h(T_2)时检测洗涤血样上清液中游离血红蛋白(FHb)的浓度。结果在NaCl浓度为0.48%～0.68%时洗涤血红细胞溶血率H组明显高于N组和L组(P0.05)。与T_0时比较,T_1、T_2时H组FHb浓度明显升高,T_2时N组和L组FHb浓度明显升高(P0.05);与T_1时比较,T_2时三组FHb浓度均明显升高(P0.05)。T_1、T_2时H组FHb浓度明显高于N组和L组(P0.05)。结论在血液回收过程中,储血器进血口位于手术野同一水平或低于手术野30 cm时对回收红细胞造成的溶血损伤低于放置在手术野上方30 cm者。     

Comparison of lactated Ringer's, gelatine and blood resuscitation on intestinal oxygen supply and mucosal tissue oxygen tension in haemorrhagic shock

Objectives. To evaluate the effects on intestinal oxygen supply,and mucosal tissue oxygen tension during haemorrhage and afterfluid resuscitation with either blood (B; n=7), gelatine (G;n=8), or lactated Ringer's solution (R; n=8) in an autoperfused,innervated jejunal segment in anaesthetized pigs. Methods. To induce haemorrhagic shock, 50% of calculated bloodvolume was withdrawn. Systemic haemodynamics, mesenteric venousand systemic acid–base and blood gas variables, and lactatemeasurements were recorded. A flowmeter was used for measuringmesenteric arterial blood flow. Mucosal tissue oxygen tension(PO₂muc), jejunal microvascular haemoglobin oxygen saturation(HbO₂) and microvascular blood flow were measured. Measurementswere performed at baseline, after haemorrhage and at four 20min intervals after fluid resuscitation. After haemorrhage,animals were retransfused with blood, gelatine or lactated Ringer'ssolution until baseline pulmonary capillary wedge pressure wasreached. Results. After resuscitation, no significant differences inmacrohaemodynamic parameters were observed between groups. Systemicand intestinal lactate concentration was significantly increasedin animals receiving lactated Ringer's solution [5.6 (1.1) vs3.3 (1.1) mmol litre^–1; 5.6 (1.1) vs 3.3 (1.2) mmol litre^–1].Oxygen supply to the intestine was impaired in animals receivinglactated Ringer's solution when compared with animals receivingblood. Blood and gelatine resuscitation resulted in higher HbO₂than with lactated Ringer's resuscitation after haemorrhagicshock [B, 43.8 (10.4)%; G, 34.6 (9.4)%; R, 28.0 (9.3)%]. PO₂mucwas better preserved with gelatine resuscitation when comparedwith lactated Ringer's or blood resuscitation [20.0 (8.8) vs13.8 (7.1) mm Hg, 15.2 (7.2) mm Hg, respectively]. Conclusion. Blood or gelatine infusion improves mucosal tissueoxygenation of the porcine jejunum after severe haemorrhagewhen compared with lactated Ringer's solution.     

Rh(D)阴性血型病人剖宫产术中成分式自体输血的安全性

目的 评价Rh(D)阴性血型病人剖宫产术中成分式自体输血的安全性.方法 拟行剖宫产术的Rh(D)阴性血型病人30例,年龄20～35岁,体重50～80 kg,ASA分级Ⅰ或Ⅱ级.静脉输注乳酸钠林格氏液7 ml/kg后经桡动脉采血,采血速率60～80 ml/min,采血同时静脉输注与采血等速率的6%羟乙基淀粉130/0.4.采集的自体血经2个循环的直接法分离为富含血小板血浆、贫血小板血浆和浓缩红细胞,每个循环以分离出红细胞后15 s时停止采血.出血量≥全身血容量的20%时立即回输自体血;出血量<全身血容量20%者,在缝合子宫后回输,依次回输富含血小板血浆、输贫血小板血浆和输浓缩红细胞.监测母体生命体征指标和胎儿心率.记录自体血采集过程中低血压和心动过速的发生情况.分别于采血前(基础状态)、采血结束时、自体血回输前和术后24 h时采集外周静脉血样,测定Hb、Hct、Plt、PT、APTT、INR和Fib.胎儿娩出后采集脐动脉血样,进行血气分析.于胎儿娩出后1、5min时行Apgar评分.记录术中出血量和异体输血情况.结果 自体血采集过程中未见低血压和心动过速的发生,胎儿HR维持在正常范围.与基础状态比较,其他时点SpO2、Hb、Hct、Plt、PT、APTT、INR和Fib差异无统计学意义(P>0.05).脐动脉血pH值、BE和乳酸浓度均在正常范围内.胎儿娩出后1、5 min时Apgar评分分别为(9.0±0.8)、(9.2±0.8)分;术中出血量(405±28)ml,所有病人未输注异体血.结论 Rh(D)阴性血型病人剖宫产术中成分式自体输血的安全性良好.

Abstract：

Objective To investigate the safety of autologous blood component transfusion during cesarean section in patients with Rh (D)-negative blood group.Methods Thirty ASA Ⅰ or Ⅱ patients of Rh (D)-negative blood group, aged 20-35 yr, weighing 50-80 kg, undergoing elective cesarean section, were enrolled in this study.After lactated Ringer' s solution 7 ml/kg was infused, blood was obtained from radial artery at a rate of 60-80ml/min, and blood volume was maintained by simultaneous infusion of 6% hydroxyethyl starch 130/0.4 at the same rate. The collected blood was subjected to two cycles of autologous blood component separation. Blood collecting during each cycle was stopped 15 s after red blood cells were separated. The autologous blood was infused when the blood loss≥20% of blood volume. The autologous blood was infused after suture of the uterus when the blood loss < 20% of blood volume. The parameters of maternal vital signs and fetal heart rate were monitored. Hypotension and tachycardia were recorded during autologous blood collecting. SpO2 was monitored routinely. Venous blood samples were taken before blood collecting (baseline), at the end of blood collecting, before autologous blood transfusion, 24 h after operation for determination of Hb, Hct, Plt, PT, APTT, INR and Fib. Umbilical arterial blood samples were obtained after delivery for blood gas analysis. Apgar score was recorded at 1 and 5 min after birth. Blood loss and allogeneic blood transfusion were also recorded. Results No hypotension and tachycardia occurred during the process of blood collecting and the fetal heart rate was within the normal range. Compared with the baseline value, there were no significant differences in SpO2 , Hb, Hct, Plt, PT, APTT, INR and FIB value at the other time points. The pH value and concentrations of base excess and lactate were within the normal range.The Apgar score was (9.0 ±0.8) and (9.2 ± 0.8) at 1 and 5 min after birth respectively. The blood loss during operation was (405 ± 28) ml and no patients received homologous blood transfusion. Conclusion The safety of autologous blood component transfusion is good during cesarean section in Rh (D)-negative blood group patients.