Transfusion-related acute lung injury: a literature review

Transfusion-related acute lung injury under general anesthesia successfully treated with extracorporeal membrane oxygenation: A case report

Transfusion-related acute lung injury (TRALI) is a serious complication of blood transfusion and can also develop severe hypoxemia. In TRALI cases with difficult blood oxygenation on mechanical ventilation support, temporary veno-venous extracorporeal membrane oxygenation support appears to maintain oxygen levels.

Reporting transfusion-related acute lung injury cases

BACKGROUND:

Transfusion-related acute lung injury (TRALI) is a rare but potentially fatal complication of blood product transfusion. It is felt worldwide that TRALI is an underrecognized and underreported entity because of lack of awareness.

AIM:

The purpose of this study was to report all cases of TRALI diagnosed in a tertiary care hospital over a 5-year period.

MATERIALS AND METHODS:

This is a retrospective review of all TRALI cases reported from January 2011 to December 2015. All TRALI cases were identified from a manual review of reported transfusion reaction forms. For detailed information of all TRALI cases, medical record charts of patients were reviewed. The record of donors implicated in TRALI cases was derived from blood bank system.

STATISTICAL ANALYSIS USED:

The rate of TRALI cases per 1000 blood products transfused was computed by dividing the transfusion reactions by total number of all blood units transfused.

RESULTS:

Total number of transfusions during the study was 291,041. Six cases of TRALI were reported during this period. Rate of TRALI per 1000 units transfused was 0.02%. The mortality associated with TRALI was 33.3%. TRALI occurred following the transfusion of fresh-frozen plasma in one patient, packed red blood cells in two patients, and a mixture of blood components in three patients. In all cases, the donors were male.

CONCLUSION:

The rate of TRALI reported to our blood bank was found to be 0.02%, which is very low as compared to international data. This is the first comprehensive study on TRALI from the country and a step forward to create awareness about the importance of diagnosing and reporting TRALI.

Effect of High-Dose Erythropoietin on Blood Transfusions in Extremely Low Gestational Age Neonates: Post Hoc Analysis of a Randomized Clinical Trial

IMPORTANCE

Extremely preterm infants are among the populations receiving the highest levels of transfusions. Erythropoietin has not been recommended for premature infants because most studies have not demonstrated a decrease in donor exposure.

OBJECTIVES

To determine whether high-dose erythropoietin given within 24 hours of birth through postmenstrual age of 32 completed weeks will decrease the need for blood transfusions.

DESIGN, SETTING, AND PARTICIPANTS

The Preterm Erythropoietin Neuroprotection Trial (PENUT) is a randomized, double-masked clinical trial with participants enrolled at 19 sites consisting of 30 neonatal intensive care units across the United States. Participants were born at a gestational age of 24 weeks (0-6 days) to 27 weeks (6-7 days). Exclusion criteria included conditions known to affect neurodevelopmental outcomes. Of 3266 patients screened, 2325 were excluded, and 941 were enrolled and randomized to erythropoietin (n = 477) or placebo (n = 464). Data were collected from December 12, 2013, to February 25, 2019, and analyzed from March 1 to June 15, 2019.

INTERVENTIONS

In this post hoc analysis, erythropoietin, 1000 U/kg, or placebo was given every 48 hours for 6 doses, followed by 400 U/kg or sham injections 3 times a week through postmenstrual age of 32 weeks.

MAIN OUTCOMES AND MEASURES

Need for transfusion, transfusion numbers and volume, number of donor exposures, and lowest daily hematocrit level are presented herein.

RESULTS

A total of 936 patients (488 male [52.1%]) were included in the analysis, with a mean (SD) gestational age of 25.6 (1.2) weeks and mean (SD) birth weight of 799 (189) g. Erythropoietin treatment (vs placebo) decreased the number of transfusions (unadjusted mean [SD], 3.5 [4.0] vs 5.2 [4.4]), with a relative rate (RR) of 0.66 (95% CI, 0.59-0.75); the cumulative transfused volume (mean [SD], 47.6 [60.4] vs 76.3 [68.2] mL), with a mean difference of -25.7 (95% CI, 18.1-33.3) mL; and donor exposure (mean [SD], 1.6 [1.7] vs 2.4 [2.0]), with an RR of 0.67 (95% CI, 0.58-0.77). Despite fewer transfusions, erythropoietin-treated infants tended to have higher hematocrit levels than placebo-treated infants, most noticeable at gestational week 33 in infants with a gestational age of 27 weeks (mean [SD] hematocrit level in erythropoietin-treated vs placebo-treated cohorts, 36.9% [5.5%] vs 30.4% [4.6%] (P < .001). Of 936 infants, 160 (17.1%) remained transfusion free at the end of 12 postnatal weeks, including 43 in the placebo group and 117 in the erythropoietin group (P < .001).

CONCLUSIONS AND RELEVANCE

These findings suggest that high-dose erythropoietin as used in the PENUT protocol was effective in reducing transfusion needs in this population of extremely preterm infants.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT01378273.

Inflammasomes in Tissue Damages and Immune Disorders After Trauma

Trauma remains a leading cause of death worldwide. Hemorrhagic shock and direct injury to vital organs are responsible for early mortality whereas most delayed deaths are secondary to complex pathophysiological processes. These processes result from imbalanced systemic reactions to the multiple aggressions associated with trauma. Trauma results in the uncontrolled local and systemic release of endogenous mediators acting as danger signals [damage-associated molecular patterns (DAMPs)]. Their recognition by the innate immune system triggers a pro-inflammatory immune response paradoxically associated with concomitant immunosuppression. These responses, ranging in intensity from inappropriate to overwhelming, promote the propagation of injuries to remote organs, leading to multiple organ failure and death. Some of the numerous DAMPs released after trauma trigger the assembly of intracellular multiprotein complexes named inflammasomes. Once activated by a ligand, inflammasomes lead to the activation of a caspase. Activated caspases allow the release of mature forms of interleukin-1β and interleukin-18 and trigger a specific pro-inflammatory cell death termed pyroptosis. Accumulating data suggest that inflammasomes, mainly NLRP3, NLRP1, and AIM2, are involved in the generation of tissue damage and immune dysfunction after trauma. Following trauma-induced DAMP(s) recognition, inflammasomes participate in multiple ways in the development of exaggerated systemic and organ-specific inflammatory response, contributing to organ damage. Inflammasomes are involved in the innate responses to traumatic brain injury and contribute to the development of acute respiratory distress syndrome. Inflammasomes may also play a role in post-trauma immunosuppression mediated by dysregulated monocyte functions. Characterizing the involvement of inflammasomes in the pathogenesis of post-trauma syndrome is a key issue as they may be potential therapeutic targets. This review summarizes the current knowledge on the roles of inflammasomes in trauma.

Non-Invasive Mechanical Ventilation in Critically Ill Trauma Patients: A Systematic Review

There is limited literature on non-invasive mechanical ventilation (NIMV) in patients with polytrauma-related acute respiratory failure (ARF). Despite an increasing worldwide application, there is still scarce evidence of significant NIMV benefits in this specific setting, and no clear recommendations are provided. We performed a systematic review, and a search of clinical databases including MEDLINE and EMBASE was conducted from the beginning of 1990 until today. Although the benefits in reducing the intubation rate, morbidity and mortality are unclear, NIMV may be useful and does not appear to be associated with harm when applied in properly selected patients with moderate ARF at an earlier stage of injury by experienced teams and in appropriate settings under strict monitoring. In the presence of these criteria, NIMV is worth attempting, but only if endotracheal intubation is promptly available because non-responders to NIMV are burdened by an increased mortality when intubation is delayed.

Mortality in vitamin K antagonist-related intracerebral bleeding treated with plasma or 4-factor prothrombin complex concentrate

Prothrombin complex concentrates (PCC) can rapidly normalise prolonged prothrombin time, induced by vitamin K antagonists (VKA). We conducted a multicentre retrospective study to investigate whether reversal of VKA coagulopathy with 4-factor PCC improves the survival of patients with VKA-related intracerebral haemorrhage as compared to plasma. We included 135 consecutive patients with VKA-related intracerebral haemorrhage treated either with plasma (mainly in Canada) or 4-factor PCC (The Netherlands and Sweden) for the reversal of VKA. Data on characteristics of the patients and the haemorrhage were collected. The volume of intracerebral haematoma was calculated from the first computed tomography (CT) scan. The unadjusted and adjusted odds ratio (OR) for 30-day all-cause mortality in both treatment groups was compared using logistic regression. Patients who received plasma (n=35, median 4 units) more often had diabetes, antiplatelet therapy, and intraventricular haemorrhage on the initial CT scans than patients who received PCC (n=100, median 22.5 IU/kg [interquartile range 20–26 IU], median of total dose 1,700 IU). The volume of intracerebral haematoma was larger in the plasma-treated group compared to the PCC-treated group (haematoma, mean 64.5 vs 36.0 cm3; p=0.021). The unadjusted OR for all-cause 30-day mortality in the PCC group was 0.40 (95% confidence interval, 0.18–0.87; p=0.021) compared to the plasma group. After adjusting for the haematoma volume, bleeding localisation and age, the effect of PCC on mortality became non-significant. In conclusion, treatment with 4-factor PCC for VKA reversal in patients with intracerebral haemorrhage does not seem to reduce the 30-day all-cause mortality compared to plasma.

Effect of premedication and other factors on the occurrence of acute transfusion reactions in dogs

OBJECTIVE

To evaluate the effect of premedication on transfusion reactions (TRs) within 24 hours after blood product transfusions in dogs.

DESIGN

Retrospective study between 2008 and 2011.

SETTING

Private veterinary referral hospital.

ANIMALS

Nine hundred and thirty-five transfusion events in 558 dogs.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Medical records of dogs receiving blood product transfusions were reviewed. Information collected included signalment, weight, transfusion product type, reason for transfusion, first or subsequent transfusion, whether an acute reaction occurred, type of reaction, whether the reaction was treated, premedication prior to the transfusion and the premedication used, other medications the animal was given, whether the animal had an immune-mediated process, and whether the transfusion was administered in the perioperative period. A total of 144 (15%) acute TRs were documented in 136 dogs. The most common TRs were fever alone (77/144 [53%]) and vomiting alone (26/144 [18%]). Six dogs died due to the TR (4%). TR was not associated with age (P = 0.257), sex (P = 0.754), weight (P = 0.829), or premedication (P = 0.312). The type of blood product transfused (P < 0.001) was significantly associated with TRs, with packed RBCs most likely associated with a TR, and plasma least likely. Immune disease (P = 0.015) was significantly associated with occurrence of a TR. Significantly fewer reactions were documented following transfusions given in the perioperative period (P = 0.023).

CONCLUSIONS

While most TRs were mild, there were some serious reactions observed including hemolysis, dyspnea, and 6 deaths. Immune-mediated disease was associated with development of a TR, while transfusion during the perioperative period was associated with lower likelihood of reaction. Packed RBC transfusions were associated with development of acute TRs. Overall occurrence of TR was not significantly altered with premedication; however, when evaluated alone, antihistamines decreased the incidence of acute allergic reactions.

Analysis of complications after blood components’ transfusions

Complications after blood components still constitute an important clinical problem and serve as limitation of liberal-transfusion strategy.

The aim of the study was to present the 5-year incidence of early blood transfusions complications and to assess their relation to the type of the transfused blood components.

Material and methods. 58,505 transfusions of blood components performed in the years 2006-2010 were retrospectively analyzed. Data concerning the amount of the transfused blood components and the numbers of adverse transfusion reactions reported to the Regional Blood Donation and Treatment Center (RBDTC) was collected.

Results. 95 adverse transfusion reactions were reportedto RBDTC 0.16% of alldonations (95/58 505) - 58 after PRBC transfusions, 28 after platelet concentrate transfusions and 9 after FFP transfusion. Febrile nonhemolytic and allergic reactions constitute respectively 36.8% and 30.5% of all complications.

Conclusion. Nonhemolyticand allergic reactions are the most common complications of blood components transfusion and they are more common after platelet concentrate transfusions in comparison to PRBC and FFP donations.

[Polytrauma with pelvic fractures and severe thoracic trauma: does the timing of definitive pelvic fracture stabilization affect the clinical course?]

BACKGROUND

The aim of this study was to investigate the influence of the surgical timing in patients with pelvic fractures and severe chest trauma on the clinical course, especially on postoperative lung function.

METHODS

A total of 47 patients were included in a prospective dual observational study. The study investigated the clinical course depending on the time of operation based on the functional lung parameters, SAPS II, SOFA and total hospital stay.

RESULTS

The average ISS was 32±6, PTS was 34±11 and TTSS was 9±3 points. The pelvic fractures were stabilized definitively after an average of 7±2 days. The early stabilization correlated significantly with a lower TTSS and SAPS II on admission (p<0.05), shorter time of ventilation (p<0.05) and stay in the intensive care unit (p<0.01) as well as the decreased need for packed red blood cells (p<0.01).

CONCLUSIONS

In this study patients with pelvic fractures and thoracic trauma benefited positively from an earlier definitive pelvic fracture stabilization with respect to a shorter time of ventilation and stay in the intensive care unit due to a lower need for red cell concentrates.

Patient blood management--the new frontier

As one of the oldest and most common procedures in clinical practice, allogeneic blood transfusions face many issues including questionable safety and efficacy, increasing costs and limited supply. The need to provide effective care for a relatively small population of patients who could not be transfused for various reasons gave rise to 'bloodless medicine and surgery', which was subsequently proposed as a care strategy for all patients, with the goal of minimising the use of allogeneic blood components. The next evolution came from the shift from a 'product-centred' approach towards a 'patient-centred' approach, that is, a focus on patient outcome rather than use of blood components, which gave birth to 'patient blood management'. Defined as "the timely application of evidence-based medical and surgical concepts designed to maintain haemoglobin concentration, optimise haemostasis and minimise blood loss in an effort to improve patient outcome", patient blood management is expected to reshape the future of transfusion medicine and the way blood components are used in clinical practice.

Early respiratory complications after liver transplantation

The poor clinical conditions associated with end-stage cirrhosis, pre-existing pulmonary abnormalities, and high comorbidity rates in patients with high Model for End-Stage Liver Disease scores are all well-recognized factors that increase the risk of pulmonary complications after orthotopic liver transplantation (OLT) surgery. Many intraoperative and postoperative events, such as fluid overload, massive transfusion of blood products, hemodynamic instability, unexpected coagulation abnormalities, renal dysfunction, and serious adverse effects of reperfusion syndrome, are other factors that predispose an individual to postoperative respiratory disorders. Despite advances in surgical techniques and anesthesiological management, the lung may still suffer throughout the perioperative period from various types of injury and ventilatory impairment, with different clinical outcomes. Pulmonary complications after OLT can be classified as infectious or non-infectious. Pleural effusion, atelectasis, pulmonary edema, respiratory distress syndrome, and pneumonia may contribute considerably to early morbidity and mortality in liver transplant patients. It is of paramount importance to accurately identify lung disorders because infectious pulmonary complications warrant speedy and aggressive treatment to prevent diffuse lung injury and the risk of evolution into multisystem organ failure. This review discusses the most common perioperative factors that predispose an individual to postoperative pulmonary complications and these complications’ early clinical manifestations after OLT and influence on patient outcome.

Predictors of pulmonary failure following severe trauma: a trauma registry-based analysis

BACKGROUND

The incidence of pulmonary failure in trauma patients is considered to be influenced by several factors such as liver injury. We intended to assess the association of various potential predictors of pulmonary failure following thoracic trauma and liver injury.

METHODS

Records of 12,585 trauma patients documented in the TraumaRegister DGU® of the German Trauma Society were analyzed regarding the potential impact of concomitant liver injury on the incidence of pulmonary failure using uni- and multivariate analyses. Pulmonary failure was defined as pulmonary failure of ≥ 3 SOFA-score points for at least two days. Patients were subdivided according to their injury pattern into four groups: group 1: AIS thorax < 3; AIS liver < 3; group 2: AIS thorax ≥ 3; AIS liver < 3; group 3: AIS thorax < 3; AIS liver ≥ 3 and group 4: AIS thorax ≥ 3; AIS liver ≥ 3.

RESULTS

Overall, 2643 (21%) developed pulmonary failure, 12% (n= 642) in group 1, 26% (n= 697) in group 2, 16% (n= 30) in group 3, and 36% (n= 188) in group 4. Factors independently associated with pulmonary failure included relevant lung injury, pre-existing medical conditions (PMC), sex, transfusion of more than 10 units of packed red blood cells (PRBC), Glasgow Coma Scale (GCS) ≤ 8, and the ISS. However, liver injury was not associated with an increased risk of pulmonary failure following severe trauma in our setting.

CONCLUSIONS

Specific factors, but not liver injury, were associated with an increased risk of pulmonary failure following trauma. Trauma surgeons should be aware of these factors for optimized intensive care treatment.

Persistent earache due to tonsillolith

Tonsilloliths are rare dystrophic calcification formed as a result of chronic inflammation of the tonsils. Tonsilloliths tend to occur more commonly with increasing age and are relatively rare in children. We report a case of unilateral tonsilloliths in an eight-year-old boy, who presented with earaches and history of regurgitating tiny yellowish-white foul smelling pellets. The tonsilloliths were successfully removed under local anaesthesia following which the symptoms subsided.

The effect of aspirin in transfusion-related acute lung injury in critically ill patients

Aspirin has been found to improve outcomes in an animal model of transfusion-related acute lung injury. We examined the association of aspirin use before admission to the intensive care unit and the development of transfusion-related acute lung injury in critically ill patients. We performed a post-hoc analysis of a nested case-control study that had been undertaken in a tertiary referral hospital. Transfusion-related acute lung injury cases were matched with controls (transfused patients not developing lung injury). Of these 218 patients, 66 used aspirin (30%). Use of aspirin did not alter the risk of transfusion-related acute lung injury after transfusion of platelets (OR 1.06, CI 0.59-1.91, p = 0.85), plasma (OR 1.06, 95% CI 0.59-1.92, p = 0.84), or red blood cells (OR 1.09, 95% CI 0.61-1.94, p = 0.77). Adjustment for confounding variables using propensity scoring also did not affect the risk of acquiring transfusion-related acute lung injury (p = 0.66). In conclusion, aspirin did not protect against transfusion-related lung injury in this cohort of critically ill patients.

Conversion to low transfusion-related acute lung injury (TRALI)-risk plasma significantly reduces TRALI

BACKGROUND

Transfusion-related acute lung injury (TRALI) is an uncommon but serious transfusion reaction. Studies have shown that the transfusion of HLA and HNA antibodies in donor plasma can lead to TRALI. Female donors are more likely to have such antibodies due to alloantigen exposure during pregnancy. Many blood suppliers have now implemented various TRALI risk reduction strategies to unknown effect. A retrospective analysis of TRALI reactions in plasma recipients before and after the conversion to low-TRALI-risk plasma (all-male donor plasma, male-predominant plasma, nulliparous female plasma, and HLA antibody-tested plasma) is reported.

STUDY DESIGN AND METHODS

Transfusion reaction reports at three large hospitals 16 months before and 16 months after the conversion to low-TRALI-risk plasma were analyzed. Respiratory reactions were categorized as TRALI, possible TRALI, or other (e.g., transfusion-associated circulatory overload or allergic reactions). Reactions were reported as a percentage of total units transfused and rates for the two time periods were compared. Trends in reaction rates for other components were also compared.

RESULTS

A total of 2156 transfusion reactions in association with 461,598 transfused blood components were reviewed. The incidence of combined TRALI or possible TRALI reactions, due to the transfusion of plasma, decreased from 0.0084% to zero (p = 0.052). The rate of TRALI or possible TRALI reactions in red blood cell and platelet recipients did not change significantly.

CONCLUSION

The conversion to low-TRALI-risk plasma has reduced the incidence of TRALI reactions in plasma recipients.

Association of allogeneic red-blood cell transfusion with surgeon case-volume

BACKGROUND

Surgeon case-volume predicts a variety of patient outcomes. We hypothesize that surgeon case-volume predicts RBC transfusion across different surgical procedures.

METHODS

We performed a cohort study of 372,670 in-patient surgical cases in the 52 non-federal hospitals in Maryland between 2004 and 2005. The main outcome measure was relative risk of receiving a transfusion.

RESULTS

Overall, 13.9% of patients received a transfusion. Patients seen by the highest case-volume surgeons (>161 cases/y) were more likely to receive a transfusion (16% versus 11%, P < 0.01) compared with middle case-volume surgeons (89-161 cases/y). After adjusting for confounders, the highest case-volume patients were still at increased risk of transfusion [relative risk (RR) 1.10, 1.07-1.14]. This result was true across many surgery types.

CONCLUSIONS

Surgeon case-volume is independently associated with the likelihood of RBC transfusion across a broad range of surgical procedures. Future efforts should be directed towards studying and standardization of transfusion practices.

Respiratory complications after oesophageal surgery

PURPOSE OF REVIEW

The most frequent complications of oesophageal surgery are respiratory and these are associated with increased critical care stay, hospital stay and mortality. This review focuses on the risk factors associated with the development of respiratory complications after oesophageal surgery.

RECENT FINDINGS

An acceptable operative mortality, increased and improved quality of life can be gained in appropriately selected patients. When induction therapy is scheduled, smoking cessation is advised. The preoperative treatment of airway pathogens can reduce postoperative complications and this may be particularly relevant in patients who have received induction chemoradiotherapy. Nonrandomized studies suggest that thoracic epidural analgesia improves outcome. Minimally invasive surgery is increasingly used and appears safe but direct comparisons to open surgery in terms of respiratory complications are awaited. Few randomized studies are available to guide anaesthetic management but anaesthetists should aim to avoid hypoxaemia, hypotension, aspiration and limit blood and fluid administration. Postoperative aspiration is common and steps to reduce it are recommended.

SUMMARY

The multifactorial nature of respiratory complications after oesophageal surgery may mean that a number of interventions are needed to have a detectable influence on outcome, much like a care bundle strategy.

Transfusion-related acute lung injury (Trali) after mastectomy with microsurgical breast reconstruction

BACKGROUND AND OBJECTIVES

After its description more than 20 years ago, TRALI--Transfusion Related Acute Lung Injury--became the main cause of transfusion-related morbidity and mortality in the United States and England. Since reliable data on its epidemiology in Brazil are not available, the difficulty to diagnose, varied clinical presentation, and absence of specific laboratory data, case reports are important. This is the first report of this transfusion reaction indexed in the LILACS data base.

CASE REPORT

A 36-year old female underwent mastectomy with microsurgical breast reconstruction under general anesthesia. Immediately after the transfusion of one unit of packed red blood cells in the post-anesthetic recovery room, she developed respiratory failure, which did not require reintubation. Supportive treatment was instituted in the intensive care unit after other diagnostic hypotheses were ruled out. She had a favorable evolution and was discharged from the hospital without sequelae.

CONCLUSION

The importance of judicious blood transfusion is emphasized since, although disease transmission is rare, TRALI is not, but it is underestimated due to the diversity of diagnostic hypotheses. Therefore, the knowledge of this disorder and its dissemination, especially in our country, is important.

Transfusion-related acute lung injury

Approximately one person in 5,000 will experience an episode of transfusion-related acute lung injury (TRALI) in conjunction with the transfusion of whole blood or blood components. Its hallmarks include hypoxemia, dyspnea, fever, hypotension, and bilateral pulmonary edema (noncardiogenic). The mortality for reported cases is 16.3%. The incidence and mortality may be even higher than estimated because of under-recognition and under-reporting. Although TRALI was identified as a clinical entity in the 1980s, a lack of consensus regarding a definition was present until 2004. An exact cause has yet to be identified; however, there are two theories regarding the etiology: the "antibody" and the "two-hit" theories. These theories involve both donor and recipient factors. Further education and research are needed to assist in the development of strategies for the prevention and treatment of TRALI.

Severe transfusion-related acute lung injury managed with extracorporeal membrane oxygenation (ECMO) in an obstetric patient

Transfusion-related acute lung injury (TRALI) is the leading cause of transfusion-related mortality in the United States. Management is usually supportive, including supplemental oxygen, intravenous fluids, and mechanical ventilation if necessary. Most patients recover within 72 hours. We present a nearly fatal case of TRALI in an obstetric patient, which was successfully managed with extracorporeal membrane oxygenation (ECMO).

Aims of obstetric critical care management

The aims of critical care management are broad. Critical illness in pregnancy is especially pertinent as the patient is usually young and previously fit, and management decisions must also consider the fetus. Assessment must consider the normal physiological changes of pregnancy, which may complicate diagnosis of disease and scoring levels of severity. Pregnant women may present with any medical or surgical problem, as well as specific pathologies unique to pregnancy that may be life threatening, including pre-eclampsia and hypertension, thromboembolic disease and massive obstetric haemorrhage. There are also increasing numbers of pregnancies in those with high-risk medical conditions such as cardiac disease. As numbers are small and clinical trials in pregnancy are not practical, management in most cases relies on general intensive care principles extrapolated from the non-pregnant population. This chapter will outline the aims of management in an organ-system-based approach, focusing on important general principles of critical care management with considerations for the pregnant and puerperal patient.

Change in use of allogeneic red blood cell transfusions among surgical patients

BACKGROUND

Although RBC transfusions can be lifesaving, recent evidence suggests that their use is associated with added morbidity and mortality and that a lower transfusion threshold is safe. It is unclear if this new evidence has translated into decreased RBC use among surgical patients. The purpose of this study is to measure the change in use of RBCs during the last decade.

STUDY DESIGN

We performed a cross-sectional cohort study of all patients who underwent inpatient operations in the 52 hospitals in Maryland in 1997 to 1998 and 2004 to 2005. The primary outcomes variable was whether or not the patient received an allogeneic RBC transfusion. We controlled for confounders related to RBC transfusion, including age, gender, race, type of admission, comorbid conditions, and surgeon patient-volume.

RESULTS

Patients receiving RBCs were older (63 versus 52 years), were more likely to be admitted through the emergency department (37% versus 24%) or as a readmission (12% versus 6.9%), had more Romano-Charlson index comorbidities, and had a higher unadjusted mortality (6.5% versus 1.1%). Comparing 1997 to 1998 to 2004 to 2005, RBC use in surgical patients increased (8.9% versus 14%), although unadjusted mortality decreased (2.0% versus 1.5%). Factors associated with higher adjusted relative risk (RR) of transfusion include age older than 65 years (RR = 2.45), unscheduled admissions (emergency department RR = 1.32, readmission RR = 1.62), Romano-Charlson comorbidities (RR = 1.04 to 2.71), third quartile of surgeon volume (RR = 1.10), death (RR = 1.24), and having operations in 2004 to 2005 (RR = 1.42).

CONCLUSIONS

Despite evidence supporting more restrictive use of RBC transfusions, RBC use among surgical patients has increased during the last decade.

Transfusion-related acute lung injury: a clinical challenge

Transfusion-related acute lung injury is a life-threatening clinical syndrome. In the last 3 years, it has become the leading cause of reported transfusion-related deaths in the United States. This syndrome is characterized by acute hypoxemia and noncardiogenic pulmonary edema directly linked in time to a blood transfusion. All types of blood products have been implicated in transfusion-related acute lung injury, but transfusion of plasma-containing products from multiparous women seems to carry the highest risk. The purpose of this article is to raise awareness of this syndrome for the critical care nurse. This article discusses the widely accepted clinical features of transfusion-related acute lung injury, its pathogenesis, differential diagnosis, and treatment.

Transfusion-related acute lung injury and leucocyte-reacting antibodies

BACKGROUND AND OBJECTIVES

Transfusion-related acute lung injury (TRALI) is underdiagnosed and underreported. This is why we present cases suspected for TRALI, in which leucocyte antibodies were examined.

MATERIAL AND METHODS

We analysed 44 patients with respiratory insufficiency, related to transfusion, who met criteria of acute lung injury (ALI). Lymphocyte and granulocyte antibodies were examined in donors and patients by six methods.

RESULTS

Based on recent trends, we divided patients into two groups: TRALI (without risk factors for ALI) and possible TRALI (with probable risk factors). The incidence of antibodies was 68.2%, the majority were human leucocyte antigen (HLA) class I and/or II, the minority were non-specific granulocyte antibodies; half of all detected antibodies, however, reacted with granulocytes. Antibodies were found in 17 donors (more often in TRALI than in possible TRALI) and in 19 patients (in four - suspected to be of the donor origin, which would diminish the number of antibodies to 15). In seven available cases, we observed cognate antigen and/or positive cross-match. In the majority of patients, TRALI occurred after transfusion of red cells, in 56.2%- stored above 14 days; all the units were non-leucoreduced. Lookback in two donors showed that transfusions in 20 patients did not result in reported TRALI, even in the patient with cognate antigen.

CONCLUSIONS

Our clinical observations suggest that to distinguish between TRALI and possible TRALI is difficult and the results are equivocal - it is worth considering whether it can be omitted. We have confirmed that antibodies are involved in TRALI, although their role is very complex. The role of stored red blood cells in the development of TRALI requires further observations in comparison with a control group of patients without TRALI.