The influence of homologous blood transfusion on immunity and clinical outcome in aortic surgery

Can Hospital Transfusion Committees Change Transfusion Practice?

Blood and blood products are commonly over-used in hospital practice. We investigated whether the introduction of a red-cell transfusion trigger (haemoglobin <8 g dL–1) influenced transfusion practice in surgery. Coronary artery bypass grafts (CABGs, n=400), total hip replacements (n=107), colectomies (n=85) and transurethral prostatectomies (TURPs, n=158) were reviewed over two periods of six months, before and after the introduction of the policy by the local hospital transfusion committee.

After introduction of the policy, the proportion of patients transfused fell from 57% to 45% with CABGs (P=0.02) and from 52% to 26% with hip replacements (P=0.006); for colectomies and TURPs there was no change. Hospital stay did not increase in any of the groups. In the second period, haemoglobin concentration on discharge was lower after total hip replacement, by a mean (95% CI) of 0.7 (0.3–1.2) g dL–1 (P=0.002) and after colectomy, by a mean of 0.6 (0.1–1.1) g dL–1 (P=0.03).

Although other factors cannot be excluded, we suggest that the reductions in red-cell transfusion were in large part attributable to the new transfusion policy.

Impact of postoperative drainage autologous blood re-transfusion on the coagulation parameters and D-dimer levels of patients after total hip arthroplasty

BACKGROUND

Postoperative drainage autologous blood re-transfusion (ABT) is an important treatment method that maintains a high haemoglobin (HGB) content and obviates the need for allogeneic blood transfusion in patients after surgery. However, the safety of ABT remains controversial.

OBJECTIVES AND METHODS

This study aimed to investigate the safety of postoperative drainage ABT in primary total hip arthroplasty (THA). In this randomized, controlled study, patients undergoing THA were selected and randomly divided into two groups. A device for postoperative ABT was used for the 49 patients in the ABT group, whereas conventional postoperative vacuum drainage was used for the 42 patients in the drainage blood (Drain) group without ABT. The coagulation parameters and D-dimer (DD) levels of the two groups of patients were recorded before surgery (T0) and on postoperative days one (T1), three (T2), seven (T3), and 14 (T4).

RESULTS

A within-group comparison after THA showed that the postoperative fibrinogen (FIB) and DD levels were higher than those before surgery in both groups (P < 0.01). A between-group comparison showed that, at different time points, the postoperative drainage blood amount and the coagulation parameters were not significantly different between the two groups. Compared with the Drain group, the DD levels in the ABT group were significantly higher at T1, T2, and T3 (P < 0.05).

CONCLUSION

Postoperative drainage ABT did not significantly impact the coagulation parameters of patients after THA. However, the DD levels after ABT significantly increased, which may affect the risk of thrombosis.

Biomarkers of inflammation in major vascular surgery: a prospective randomised trial

BACKGROUND

Surgery induces inflammation and pro-inflammatory cytokines are associated with post-operative complications. In cardiac surgery, it has been shown that volatile anaesthetics have cardioprotective properties. We explored whether sevoflurane affects the pro-inflammatory response favourably compared with total intravenous anaesthesia (TIVA) after surgery.

METHODS

We measured monocyte chemotactic protein 1 (MCP-1), matrix metalloproteinase 9 (MMP-9), C-reactive protein (CRP), vascular cell adhesion molecule 1 (VCAM-1), interleukin (IL)-6 and IL-8 perioperatively and evaluated if the anaesthetic regimen affected these mediators. Our hypothesis was that sevoflurane-based anaesthesia is associated with a reduced release of biomarkers of inflammation compared with TIVA with propofol/remifentanil.

RESULTS

In the total population, MCP-1, MMP-9, IL-6 and IL-8 increased 30 min after arrival intensive care unit, compared with before surgery (P < 0.001), whereas CRP and VCAM-1 transiently declined (P < 0.001). From 30 min after arrival intensive care unit to 1st post-operative day, MCP-1 and IL-6 levels declined (P < 0.001), CRP and VCAM-1 increased (P < 0.001), whereas MMP-9 and IL-8 were not significantly altered. Pre-operatively there were no significant differences in any variables between the two anaesthetic groups. Lower levels of MCP-1 and IL-8 (P < 0.001) and higher levels of IL-6 and MMP-9 (P = 0.003) were found in the sevoflurane group, compared with the TIVA group 30 min post-operatively. CRP and VCAM-1 levels did not differ. There were no significant differences between the two anaesthetic groups before surgery or at 1st post-operative day.

CONCLUSION

We found an inflammatory response during the observation period, which was modified by the anaesthetic regimen in the early phase. This short-lasting difference is probably too short to support a cardioprotective effect of sevoflurane compared with TIVA in open abdominal aortic surgery.

Identification of predictive factors for perioperative blood transfusion in colorectal resection patients

BACKGROUND

Blood transfusion is associated with higher postoperative complication. With the availability of autologous blood and erythropoietin, it would be advantageous to identify patients who are at higher risk for requiring blood transfusion. Our aim is to identify possible predictive factors for perioperative blood transfusion in patients undergoing colorectal resection. We examined 206 patients who underwent colorectal resections.

MATERIALS AND METHODS

We analyzed factors including preoperative hematocrit, age, history of radiation, type of resection, operative blood loss, additional surgical procedure, surgery duration, and comorbidity.

RESULTS

Forty-one patients (19.9%) received perioperative blood transfusion. Twenty patients (55.6%) with preoperative hematocrit less than 30 received transfusion (p<0.0001). Twenty-one patients (12.4%) with preoperative hematocrit greater than 30 received perioperative blood transfusion. Thirty-three patients (17.9%) under 65 years received transfusion. Eight patients (36.4%) more than the age of 65 received transfusion (p=0.05). Ten patients (16.1%) without any comorbidity received transfusion, whereas ten patients (15.1%) with one comorbidity, ten patients (22.2%) with two comorbidities, and 11 patients (33.3%) with greater than three comorbidities received blood transfusion (p=0.07). In the multivariate analysis, relative risk of perioperative blood transfusion was 3.63 for patients with preoperative hematocrit less than 30 (p<0.0001), 1.26 for patients more than the age of 65 (p=0.49), and 1.07 for each comorbidity (p=0.62). Patients with higher number of comorbidities and age greater than 65 tend to have lower preoperative hematocrit than other patients.

CONCLUSION

Hematocrit less than 30 is an independent risk factor for requiring perioperative blood transfusion, and patients with hematocrit less than 30 should be considered for autologous blood transfusion and erythropoietin.

Massive blood transfusion and outcome in 1062 polytrauma patients: a prospective study based on the Trauma Registry of the German Trauma Society

BACKGROUND AND OBJECTIVES

About 15% of polytrauma patients receive massive blood transfusion (MBT) defined as > or = 10 units of packed red blood cells (PRBC). In general, the prognosis of trauma patients receiving MBT is considered to be poor. The purpose of this study was to investigate the impact of MBT on the outcome of polytrauma patients.

MATERIALS AND METHODS

Records of 10 997 patients in the Trauma Registry of the German Trauma Society were analysed. Transfusion data were available from 8182 severe trauma patients with a mean injury severity score of 24.5 and, of these 8182 patients, 1062 received > or = 10 units of PRBC. First, a logistic regression model for the predictors of mortality was performed. Second, incidences of organ failure and sepsis as well as survival rates were analysed.

RESULTS

The highest risk for mortality was age over 55 years (odds ratios [OR] 4.7; confidence intervals [CI 95%], 3.5-6.5) followed by Glasgow Coma Scale < or = 8 (OR 4.6; 3.4-6.1), MBT > or = 20 units of PRBC (OR 3.3; 2.1-5.4), thromboplastin time < 50% (OR 3.2; 2.2-4.4) and injury severity score > or = 24 (OR 2.9; 2.1-4.1). Transfusion of 10-19 PRBC was identified as the variable with the lowest risk for mortality (OR 1.5; 1.0-2.3). Risk of organ failure, sepsis and death correlated with increasing transfusion amount. For the MBT patients, the survival rate was 56.9% (CI 95%, 53.9-59.9%) compared to 85.2% (84.4-86.0%) of non-MBT patients (P < 0.001). In the MBT group with > 30 PRBC (mean 40.6 PRBC) 39.6% survived (31.7-47.5%).

CONCLUSION

Massive blood transfusion is one main prognostic factor for mortality in trauma. Although MBT is generally considered to be critical, every second trauma patient with MBT survived. A cut-off value for the number of PRBC could not be determined. Extended transfusion management even with high amounts of PRBC seems to be justified.

Aprotinin does not diminish blood loss in elective operations for infrarenal abdominal aneurysms: a randomized double-blind controlled trial

Surgery for abdominal aneurysm is associated with substantial blood loss. In cardiac surgery, aprotinin, a fibrinolysis inhibitor, has shown to reduce blood loss significantly. Our aim was to assess the effect of aprotinin, when administered during elective surgery of infrarenal abdominal aneurysm, on coagulation, blood loss, and morbidity. A double-blind randomized trial was performed on 35 consecutive patients. They were randomized to either an aprotinin or a placebo group. The aprotinin group received 2,000,000 kallikrein inhibiting units (KIU) of aprotinin (500,000 KIU in 50 mL NaCl 0.9%) as a starting dose, followed by 500,000 KIU per hour during the operation. The placebo group received equal amounts of only NaCl 0.9%. During the operation and 24 hr thereafter, blood samples were taken to assess coagulation factors. Blood loss was measured in suction devices and swabs. All patients were followed until their discharge from the hospital. Statistical analysis was performed by independent t-test or Mann-Whitney U-test and chi-squared test. There was no significant difference in the amount of blood loss or the amount of blood products administered between the two groups. Morbidity and mortality were also comparable. In both groups, consumption of clotting factors could be detected, indicating activation of the coagulation cascade. However, in the aprotinin group, the alpha2-antiplasmin level was raised during surgery, indicating inhibition of fibrinolysis. Administration of aprotinin during elective operations for infrarenal aortic aneurysm induces inhibition of fibrinolysis. However, it does not significantly reduce blood loss or the need for blood products.

[Survival after blood transfusion: a study at Rouen university hospital]

The aim of this study was to estimate short term survival rate after blood transfusion according to various criteria.

PATIENTS AND METHODS

Patients admitted and transfused from January, 1 until June, 30 1996 at Rouen university hospital were retrospectively included, and their status (alive or dead) was determined. The characteristics of patients admitted and transfused were compared to the overall population of inpatients. Independent factors associated with mortality six months after blood transfusion were evaluated using Cox model.

RESULTS

During the study period, 1887 patients were transfused. These patients were older, more often admitted in surgical or in intensive care units, and had a longer duration of stay, than the overall inpatients population. The survival rate at six months in transfused patients was 76.1%. Mortality rate at six months was independently higher in patients aged 75 and older, in men, in patients admitted in intensive care units, or transfused with homologous fresh-frozen plasma or packed platelet blood cells. Mortality rate was lower in patients who underwent a surgical procedure, in children under 16, and in patients whose stay was classified in "Circulatory system disorders", "Musculoskeletal system and connective tissues disorders or trauma", or "Injuries, allergy or poisoning".

CONCLUSION

In this study implemented in a teaching hospital inpatients receiving blood transfusion, the survival was mainly associated with the severity and characteristics of the diseases requiring transfusion.

Supernatant from stored red blood cell primes inflammatory cells: influence of prestorage white cell reduction

BACKGROUND

The contribution of RBC transfusion to adverse patient outcomes is controversial. There is conflicting clinical data and limited biologic data that provide an underpinning biologic rationale for any adverse impacts from RBC transfusion. This study used in-vitro measures of PMN stimulation to determine the ability of supernatant from RBCs to stimulate allogeneic WBCs and to determine the influence of residual donor WBCs and storage time on the proinflammatory potential of RBCs.

STUDY DESIGN AND METHODS

Three types of RBCs were assessed: standard non-WBC-reduced RBCs (S-RBCs), buffy coat-poor RBCs (BCP-RBCs), and prestorage WBC-filtered RBC (LF-RBCs). Supernatant was collected weekly up to Day 42 of storage. PMN priming by supernatant from RBCs was determined by three methods: induction of CD11b expression on PMNs, induction of IL-8 release from PMNs, and the chemotactic effect of supernatant on PMNs.

RESULTS

Supernatant from S-RBCs induced the expression of CD11b on PMNs, primed PMNs to release IL-8, and was chemotactic for PMNs. The magnitude of this PMN-priming progressively amplified with storage time. In contrast, supernatant from BCP-RBCs or LF-RBCs did not significantly prime PMNs. The PMN-priming effect of supernatant from RBCs correlated more closely with the level of MNCs in the RBCs than PMN content.

CONCLUSION

Supernatant from stored S-RBCs prime unstimulated allogeneic PMNs in vitro. Prestorage buffy-coat WBC reduction was as effective as WBC depletion in abrogating this proinflammatory response elicited by supernatants from RBCs. The clinical consequences, if any, of these findings for transfusion recipients are unknown.

Efficacy of a criterion-driven transfusion protocol in patients having pediatric cardiac surgery

OBJECTIVES

Low-hematocrit bypass is one technique used to prevent allogeneic transfusion during cardiopulmonary bypass. The purpose of this study is to determine the efficacy of a criterion-driven transfusion protocol and the effect of low-hematocrit bypass with moderate hypothermia in pediatric cardiac surgery.

METHODS

Seventy-five children who underwent cardiopulmonary bypass with low-hematocrit bypass for repair of congenital heart disease were studied. Criteria for red blood cell transfusion included anemia with a hematocrit level of less than 15% during bypass and 20% after bypass. During cardiopulmonary bypass, venous oxygen saturation, hematocrit values, and regional cerebral oxygenation were continuously monitored. Arterial lactate levels were measured postoperatively.

RESULTS

All patients had an uncomplicated perioperative course, and no perioperative death occurred. Twenty-two patients (29.3%) received a transfusion, and 53 (70.7%) patients did not. The hematocrit levels before and after modified ultrafiltration in the transfused group (21.6 +/- 5.5%, 26.6 +/- 6.5%) were significantly higher than those in the nontransfused group (18.9 +/- 3.7%, 23.1 +/- 4.1%) (P <.05). There was no significant difference between the group's arterial lactate levels immediately after admission to the intensive care unit and 1 day after the operation. The arterial lactate levels 6 hours after the admission to the intensive care unit for the nontransfused patients were higher than with the transfused patients (4.3 +/- 3.0 versus 2.5 +/- 1.5 mmol/L, (P <.05). For arterial lactate level, the relation with patients' weight had the highest correlation (R = 0.678, P <.0001).

CONCLUSIONS

A criterion-driven transfusion program can be effective, and low-hematocrit bypass with a hematocrit value below 20% may affect lactate production or clearance from the body.

The role of hospital transfusion committees in blood product conservation

Transfusion committees have been created in different countries to oversee all aspects of blood product transfusion within individual institutions. A fundamental role of hospital transfusion committees is to ensure appropriate blood product use by developing local policies, educating clinicians, and auditing blood use. Unfortunately, this task is hampered by the lack of universally accepted criteria for blood product transfusion. Several examples of specific interventions directed toward improving blood use have been described in the literature. Despite some limitations of these reports, largely because of shortfalls in study design, such interventions appear to be generally effective, but there is not enough evidence to recommend a specific course of action to ensure appropriate blood use. Notwithstanding such problems, a functional hospital transfusion committee can have a major impact on local rates of inappropriate transfusion.

Blood transfusion, independent of shock severity, is associated with worse outcome in trauma

BACKGROUND

We have previously shown that blood transfusion in the first 24 hours is an independent predictor of mortality, intensive care unit (ICU) admission, and increased ICU length of stay in the acute trauma setting when controlling for Injury Severity Score, Glasgow Coma Scale score, and age. Indices of shock such as base deficit, serum lactate level, and admission hemodynamic status (systolic blood pressure, heart rate) and admission hematocrit were considered potential confounding variables in that study. The objectives of this study were to evaluate admission anemia and blood transfusion within the first 24 hours as independent predictors of mortality, ICU admission, ICU length of stay (LOS), and hospital LOS, with serum lactate level, base deficit, and shock index (heart rate/systolic blood pressure) as covariates.

METHODS

Prospective data were collected on 15,534 patients admitted to a Level I trauma center over a 3-year period (1998-2000) and stratified by age, gender, race, Glasgow Coma Scale score, and Injury Severity Score. Admission anemia and blood transfusion were assessed as independent predictors of mortality, ICU admission, ICU LOS, and hospital LOS by logistic regression analysis, with base deficit, serum lactate, and shock index as covariates.

RESULTS

Blood transfusion was a strong independent predictor of mortality (odds ratio [OR], 2.83; 95% confidence interval [CI], 1.82-4.40; p < 0.001), ICU admission (OR, 3.27; 95% CI, 2.69-3.99; p < 0.001), ICU LOS (p < 0.001), and hospital LOS (Coef, 4.37; 95% CI, 2.79-5.94; p < 0.001) when stratified by indices of shock (base deficit, serum lactate, shock index, and anemia). Patients who underwent blood transfusion were almost three times more likely to die and greater than three times more likely to be admitted to the ICU. Admission anemia (hematocrit < 36%) was an independent predictor of ICU admission (p = 0.008), ICU LOS (p = 0.012), and hospital LOS (p < 0.001).

CONCLUSION

Blood transfusion is confirmed as an independent predictor of mortality, ICU admission, ICU LOS, and hospital LOS in trauma after controlling for severity of shock by admission base deficit, lactate, shock index, and anemia. The use of other hemoglobin-based oxygen-carrying resuscitation fluids (such as human or bovine hemoglobin substitutes) in the acute postinjury period warrants further investigation.

Can hospital transfusion committees change transfusion practice?

Blood and blood products are commonly over-used in hospital practice. We investigated whether the introduction of a red-cell transfusion trigger (haemoglobin <8 g dL(-1)) influenced transfusion practice in surgery. Coronary artery bypass grafts (CABGs, n=400), total hip replacements (n=107), colectomies (n=85) and transurethral prostatectomies (TURPs, n=158) were reviewed over two periods of six months, before and after the introduction of the policy by the local hospital transfusion committee. After introduction of the policy, the proportion of patients transfused fell from 57% to 45% with CABGs (P=0.02) and from 52% to 26% with hip replacements (P=0.006); for colectomies and TURPs there was no change. Hospital stay did not increase in any of the groups. In the second period, haemoglobin concentration on discharge was lower after total hip replacement, by a mean (95% CI) of 0.7 (0.3-1.2) g dL(-1) (P=0.002) and after colectomy, by a mean of 0.6 (0.1-1.1) g dL(-1) (P=0.03). Although other factors cannot be excluded, we suggest that the reductions in red-cell transfusion were in large part attributable to the new transfusion policy.

Economic evaluation of a randomized clinical trial of haemodilution with cell salvage in aortic surgery

BACKGROUND

This study evaluated the costs of acute normovolaemic haemodilution (ANH) and intraoperative cell salvage (ICS) versus homologous blood transfusion in aortic surgery in a prospective multicentre randomized trial.

METHODS

One hundred and forty-five patients were randomized either to standard transfusion practice (homologous) or to a combination of ANH and ICS (autologous). Costs for each inpatient admission were identified. Cell salvage costs were assigned on the assumption that 50 operations were done each year employing a trained cell salvage operator. The results were analysed statistically using bias-corrected bootstrap analysis.

RESULTS

Patients who had transfusion of homologous blood received some 251 units and those having a homologous transfusion received 103 units (P = 0.008). There was no difference in morbidity, mortality and duration of hospital stay. Transfusion-related mean costs were similar at 340 UK pounds for patients having a homologous transfusion and 357 UK pounds for those receiving autologous blood (mean difference 17 UK pounds (95 per cent confidence interval [c.i.]--184 UK pounds to 174 UK pounds); P not significant). There was also no significant difference in mean overall costs: 5859 UK pounds for homologous and 5384 UK pounds for autologous transfusion (mean difference--475 UK pounds (95 per cent c.i.--2231 UK pounds to 1342 UK pounds)). Sensitivity analysis showed that costs remained similar for 20 and 150 operations per annum. Exclusion of a dedicated cell salvage operator reduced autologous transfusion costs but did not have a significant impact on overall cost.

CONCLUSION

Autologous transfusion is cost neutral in aortic surgery even when surgical activity is low.