The anesthesiologist's perspective on emergency aortic surgery: Preoperative optimization, intraoperative management, and postoperative surveillance

The management of emergencies related to the aorta requires a multidisciplinary approach involving various health care professionals. Despite technological advancements in treatment methods, the risks and mortality rates associated with surgery remain high. In the emergency department, definitive diagnosis is usually obtained through computed tomography angiography, and management focuses on controlling blood pressure and treating symptoms to prevent further deterioration. Preoperative resuscitation is the main focus, followed by intraoperative management aimed at stabilizing the patient's hemodynamics, controlling bleeding, and protecting vital organs. After the operation, factors such as organ protection, transfusion management, pain control, and overall patient care must be taken into account. Endovascular techniques are becoming more common in surgical treatment, but they also present new challenges in terms of complications and outcomes. It is recommended that patients with suspected ruptured abdominal aortic aneurysms be transferred to facilities with both open and endovascular treatment options and a track record of successful outcomes to ensure the best patient care and long-term results. To achieve optimal patient outcomes, close collaboration and regular case discussions between health care professionals are necessary, as well as participation in educational programs to promote a culture of teamwork and continuous improvement.

Benefits of Prehabilitation before Complex Aortic Surgery

The purpose of this narrative review was to detail and discuss the underlying principles and benefits of preoperative interventions addressing risk factors for perioperative adverse events in open aortic surgery (OAS). The term "complex aortic disease" encompasses juxta/pararenal aortic and thoraco-abdominal aneurysms, chronic aortic dissection and occlusive aorto-iliac pathology. Although endovascular surgery has been increasingly favored, OAS remains a durable option, but by necessity involves extensive surgical approaches and aortic cross-clamping and requires a trained multidisciplinary team. The physiological stress of OAS in a fragile and comorbid patient group mandates thoughtful preoperative risk assessment and the implementation of measures dedicated to improving outcomes. Cardiac and pulmonary complications are one of the most frequent adverse events following major OAS and their incidences are correlated to the patient's functional status and previous comorbidities. Prehabilitation should be considered in patients with risk factors for pulmonary complications including advanced age, previous chronic obstructive pulmonary disease, and congestive heart failure with the aid of pulmonary function tests. It should also be combined with other measures to improve postoperative course and be included in the more general concept of enhanced recovery after surgery (ERAS). Although the current level of evidence regarding the effectiveness of ERAS in the setting of OAS remains low, an increasing body of literature has promoted its implementation in other specialties. Consequently, vascular teams should commit to improving the current evidence through studies to make ERAS the standard of care for OAS.

Drugs to reduce bleeding and transfusion in major open vascular or endovascular surgery: a systematic review and network meta-analysis

BACKGROUND

Vascular surgery may be followed by internal bleeding due to inadequate surgical haemostasis, abnormal clotting, or surgical complications. Bleeding ranges from minor, with no transfusion requirement, to massive, requiring multiple blood product transfusions. There are a number of drugs, given systemically or applied locally, which may reduce the need for blood transfusion.

OBJECTIVES

To assess the effectiveness and safety of anti-fibrinolytic and haemostatic drugs and agents in reducing bleeding and the need for blood transfusion in people undergoing major vascular surgery or vascular procedures with a risk of moderate or severe (> 500 mL) blood loss.

SEARCH METHODS

We searched: Cochrane Central Register of Controlled Trials; MEDLINE; Embase; CINAHL, and Transfusion Evidence Library. We also searched the WHO ICTRP and ClinicalTrials.gov trial registries for ongoing and unpublished trials. Searches used a combination of MeSH and free text terms from database inception to 31 March 2022, without restriction on language or publication status.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) in adults of drug treatments to reduce bleeding due to major vascular surgery or vascular procedures with a risk of moderate or severe blood loss, which used placebo, usual care or another drug regimen as control.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were units of red cells transfused and all-cause mortality. Our secondary outcomes included risk of receiving an allogeneic blood product, risk of reoperation or repeat procedure due to bleeding, risk of a thromboembolic event, risk of a serious adverse event and length of hospital stay. We used GRADE to assess certainty of evidence.

MAIN RESULTS

We included 22 RCTs with 3393 participants analysed, of which one RCT with 69 participants was reported only in abstract form, with no usable data. Seven RCTs evaluated systemic drug treatments (three aprotinin, two desmopressin, two tranexamic acid) and 15 RCTs evaluated topical drug treatments (drug-containing bioabsorbable dressings or glues), including fibrin, thrombin, collagen, gelatin, synthetic sealants and one investigational new agent. Most trials were conducted in high-income countries and the majority of the trials only included participants undergoing elective surgery. We also identified two ongoing RCTs. We were unable to perform the planned network meta-analysis due to the sparse reporting of outcomes relevant to this review. Systemic drug treatments We identified seven trials of three systemic drugs: aprotinin, desmopressin and tranexamic acid, all with placebo controls. The trials of aprotinin and desmopressin were small with very low-certainty evidence for all of our outcomes. Tranexamic acid versus placebo was the systemic drug comparison with the largest number of participants (2 trials; 1460 participants), both at low risk of bias. The largest of these included a total of 9535 individuals undergoing a number of different higher risk surgeries and reported limited information on the vascular subgroup (1399 participants). Neither trial reported the number of units of red cells transfused per participant up to 30 days. Three outcomes were associated with very low-certainty evidence due to the very wide confidence intervals (CIs) resulting from small study sizes and low number of events. These were: all-cause mortality up to 30 days; number of participants requiring an allogeneic blood transfusion up to 30 days; and risk of requiring a repeat procedure or operation due to bleeding. Tranexamic acid may have no effect on the risk of thromboembolic events up to 30 days (risk ratio (RR) 1.10, 95% CI 0.88 to 1.36; 1 trial, 1360 participants; low-certainty evidence due to imprecision). There is one large ongoing trial (8320 participants) comparing tranexamic acid versus placebo in people undergoing non-cardiac surgery who are at high risk of requiring a red cell transfusion. This aims to complete recruitment in April 2023. This trial has primary outcomes of proportion of participants transfused with red blood cells and incidence of venous thromboembolism (DVT or PE). Topical drug treatments Most trials of topical drug treatments were at high risk of bias due to their open-label design (compared with usual care, or liquids were compared with sponges). All of the trials were small, most were very small, and few reported clinically relevant outcomes in the postoperative period. Fibrin sealant versus usual care was the topical drug comparison with the largest number of participants (5 trials, 784 participants). The five trials that compared fibrin sealant with usual care were all at high risk of bias, due to the open-label trial design with no measures put in place to minimise reporting bias. All of the trials were funded by pharmaceutical companies. None of the five trials reported the number of red cells transfused per participant up to 30 days or the number of participants requiring an allogeneic blood transfusion up to 30 days. The other three outcomes were associated with very low-certainty evidence with wide confidence intervals due to small sample sizes and the low number of events, these were: all-cause mortality up to 30 days; risk of requiring a repeat procedure due to bleeding; and risk of thromboembolic disease up to 30 days. We identified one large trial (500 participants) comparing fibrin sealant versus usual care in participants undergoing abdominal aortic aneurysm repair, which has not yet started recruitment. This trial lists death due to arterial disease and reintervention rates as primary outcomes.

AUTHORS' CONCLUSIONS

Because of a lack of data, we are uncertain whether any systemic or topical treatments used to reduce bleeding due to major vascular surgery have an effect on: all-cause mortality up to 30 days; risk of requiring a repeat procedure or operation due to bleeding; number of red cells transfused per participant up to 30 days or the number of participants requiring an allogeneic blood transfusion up to 30 days. There may be no effect of tranexamic acid on the risk of thromboembolic events up to 30 days, this is important as there has been concern that this risk may be increased. Trials with sample size targets of thousands of participants and clinically relevant outcomes are needed, and we look forward to seeing the results of the ongoing trials in the future.

Risk factor prediction of severe postoperative acute kidney injury at stage 3 in patients with acute type A aortic dissection using thromboelastography

Objective

Perioperative blood transfusions and postoperative drainage volume not only are the commonly recognized risk factors for acute kidney injury (AKI) but also are indirect indicators of coagulopathy in patients with acute type A aortic dissection (ATAAD). However, standard laboratory tests fail to accurately reflect and assess the overall coagulopathy profile in patients with ATAAD. Thus, this study aimed to explore the association between the hemostatic system and severe postoperative AKI (stage 3) in patients with ATAAD using thromboelastography (TEG).

Methods

We selected 106 consecutive patients with ATAAD who underwent emergency aortic surgery at Beijing Anzhen Hospital. All participants were categorized into the stage 3 and non-stage 3 groups. The hemostatic system was evaluated using routine laboratory tests and TEG preoperatively. We undertook univariate and multivariate stepwise logistic regression analyses to determine the potential risk factors for severe postoperative AKI (stage 3), with a special investigation on the association between hemostatic system biomarkers and severe postoperative AKI (stage 3). The receiver operating characteristic (ROC) curves were generated to assess the predictive ability of hemostatic system biomarkers for severe postoperative AKI (stage 3).

Results

A total of 25 (23.6%) patients developed severe postoperative AKI (stage 3), including 21 patients (19.8%) who required continuous renal replacement therapy (RRT). Multivariate logistic regression analysis demonstrated that the preoperative fibrinogen level (OR, 2.02; 95% CI, 1.03 to 3.00; p = 0.04), platelet function (MA level) (OR, 1.23; 95% CI, 1.09 to 1.39; p = 0.001), and cardiopulmonary bypass (CPB) time (OR, 1.01; 95% CI, 1.00 to 1.02; p = 0.02) were independently associated with severe postoperative AKI (stage 3). The cutoff values of preoperative fibrinogen and platelet function (MA level) for predicting severe postoperative AKI (stage 3) were determined to be 2.56 g/L and 60.7 mm in the ROC curve [area under the curve (AUC): 0.824 and 0.829; p < 0.001].

Conclusions

The preoperative fibrinogen level and platelet function (measured by the MA level) were identified as potential predictive factors for developing severe postoperative AKI (stage 3) in patients with ATAAD. Thromboelastography could be considered a potentially valuable tool for real-time monitoring and rapid assessment of the hemostatic system to improve postoperative outcomes in patients.

Anaesthesia for vascular emergencies - a state of the art review

In this state-of-the-art review, we discuss the presenting symptoms and management strategies for vascular emergencies. Although vascular emergencies are best treated at a vascular surgical centre, patients may present to any emergency department and may require both immediate management and safe transport to a vascular centre. We describe the surgical and anaesthetic considerations for management of aortic dissection, aortic rupture, carotid endarterectomy, acute limb ischaemia and mesenteric ischaemia. Important issues to consider in aortic dissection are extent of the dissection and surgical need for bypasses in addition to endovascular repair. From an anaesthetist's perspective, aortic dissection requires infrastructure for massive transfusion, smooth management should an endovascular procedure require conversion to an open procedure, haemodynamic manipulation during stent deployment and prevention of spinal cord ischaemia. Principles in management of aortic rupture, whether open or endovascular treatment is chosen, include immediate transfer to a vascular care centre; minimising haemodynamic changes to reduce aortic shear stress; permissive hypotension in the pre-operative period; and initiation of massive transfusion protocol. Carotid endarterectomy for carotid stenosis is managed with general or regional techniques, and anaesthetists must be prepared to manage haemodynamic, neurological and airway issues peri-operatively. Acute limb ischaemia is a result of embolism, thrombosis, dissection or trauma, and may be treated with open repair or embolectomy, under either general or local anaesthesia. Due to hypercoagulability, there may be higher numbers of acutely ischaemic limbs among patients with COVID-19, which is important to consider in the current pandemic. Mesenteric ischaemia is a rare vascular emergency, but it is challenging to diagnose and associated with high morbidity and mortality. Several peri-operative issues are common to all vascular emergencies: acute renal injury; management of transfusion; need for heparinisation and reversal; and challenging postoperative care. Finally, the important development of endovascular techniques for repair in many vascular emergencies has improved care, and the availability of transoesophageal echocardiography has improved monitoring as well as aids in surgical placement of endovascular grafts and for post-procedural evaluation.

Management of Acute Complications during Endovascular Procedures in Peripheral Arterial Disease: A Review

Endovascular therapy, as opposed to surgical bypass, has become the mainstay for peripheral arterial disease even in long segment occlusions. Complications can occur during the arterial access, catheter manipulation, balloon dilation, and/or stent placement. Given the high prevalence of comorbidities such as diabetes, hypertension, renal dysfunction, and coronary artery disease in these patients, early identification of procedural complications and initiation of treatment are of paramount importance. This review aims to provide comprehensive data on the identification and management of commonly encountered endovascular complications during endovascular interventions in peripheral arterial disease.

Patient Blood Management in Vascular Surgery

Patient blood management (PBM) is an evidence-based, multidisciplinary approach aimed at appropriately allocating blood products to patients requiring transfusion while simultaneously minimizing inappropriate transfusions. The 3 pillars of patient blood management are optimizing erythropoiesis, minimizing blood loss, and optimizing physiological reserve of anemia. Benefits seen from PBM include limiting hospital costs and mitigating harm from numerous risks of transfusion.

A prospective, controlled study on the utility of rotational thromboelastometry in surgery for acute type A aortic dissection

To evaluate the hemostatic system with ROTEM in patients undergoing surgery for acute type aortic dissection (ATAAD) using elective aortic procedures as controls. This was a prospective, controlled, observational study. The study was performed at a tertiary referral center and university hospital. Twenty-three patients with ATAAD were compared to 20 control patients undergoing elective surgery of the ascending aorta or the aortic root. ROTEM (INTEM, EXTEM, HEPTEM and FIBTEM) was tested at 6 points in time before, during and after surgery for ATAAD or elective aortic surgery. The ATAAD group had an activated coagulation coming into the surgical theatre. The two groups showed activation of both major coagulation pathways during surgery, but the ATAAD group consistently had larger deficiencies. Reversal of the coagulopathy was successful, although none of the groups reached elective baseline until postoperative day 1. ROTEM did not detect low levels of clotting factors at heparin reversal nor low levels of platelets. This study demonstrated that ATAAD is associated with a coagulopathic state. Surgery causes additional damage to the hemostatic system in ATAAD patients as well as in patients undergoing elective surgery of the ascending aorta or the aortic root. ROTEM does not adequately catch the full coagulopathy in ATAAD. A transfusion protocol in ATAAD should be specifically created to target this complex coagulopathic state and ROTEM does not negate the need for routine laboratory tests.

Postoperative Intensive Care Management of Aortic Repair

Vascular surgery patients have multiple comorbidities and are at high risk for perioperative complications. Aortic repair surgery has greatly evolved in recent years, with an increasing predominance of endovascular techniques (EVAR). The incidence of cardiac complications is significantly reduced with endovascular repair, but high-risk patients require postoperative ST-segment monitoring. Open aortic repair may portend a prohibitive risk of respiratory complications that could be a contraindication for surgery. This risk is greatly reduced in the case of an endovascular approach, and general anesthesia should be avoided whenever possible in the case of endovascular repair. Preoperative renal function and postoperative kidney injury are powerful determinants of short- and long-term outcome, so that preoperative risk stratification and secondary prevention are critical tasks. Intraoperative renal protection with selective renal and distal aortic perfusion is essential during open repair. EVAR has lower rates of postoperative renal failure compared to open repair, with approximately half the risk for acute kidney injury (AKI) and one-third of the risk of hemodialysis requirement. Spinal cord ischemia used to be the most distinctive and feared complication of aortic repair. The risk has significantly decreased since the beginning of aortic surgery, with advances in surgical technique and spinal protection protocols, and is lower with endovascular repair. Endovascular repair avoids extensive aortic dissection and aortic cross-clamping and is generally associated with reduced blood loss and less coagulopathy. The intensive care physician must be aware that aortic repair surgery has an impact on every organ system, and the importance of early recognition of organ failure cannot be overemphasized.

Associations Between Preoperative Risk, Postoperative Complications, and 30-Day Mortality

BACKGROUND

Comorbidities and postoperative complications increase mortality, making early recognition and management critical. It is useful to understand how they are associated with one another. This study assesses associations between comorbidities, complications, and mortality.

METHODS

We calculated associations between comorbidities, complications, and 30-day mortality using the 2012-2018 ACS-NSQIP database. We examined the association between mortality and number of complications which complications were most associated with mortality.

RESULTS

5,777,108 patients were included. 30-day mortality was 0.95%. For most comorbidities or postoperative complications, patients with these had higher mortality than patients without. Having ≥ 1 complication increased mortality risk by 32.5-fold (6.5% vs. 0.2%). Mortality rate significantly increased with increasing number of complications, particularly after two or more complications. Bleeding and sepsis were associated with the most deaths.

CONCLUSION

The 30-day mortality rate was < 1% but was 32-fold higher in patients with complications and increased rapidly for patients with ≥ 2 complications. Bleeding and sepsis were the most prominent complications associated with mortality.

Altered Fibrinolysis during and after Surgery

Major surgery induces hemostatic changes related to surgical stress, tissue destruction, and inflammatory reactions. These changes involve a shift of volume from extravascular space to intravascular and interstitial spaces, a "physiologic" hemodilution of coagulation proteins, and an increase of plasmatic fibrinogen concentration and platelets. Increases in fibrinogen and platelets together with a simultaneous dilution of pro- and anticoagulant factors and development of a hypofibrinolytic status result in a postoperative hypercoagulable state. This profile is accentuated in more extensive surgery, but the balance can shift toward hemorrhagic tendency in specific types of surgeries, for example, in prolonged cardiopulmonary bypass or in patients with comorbidities, especially liver diseases, sepsis, and hematological disorders. Also, acquired coagulopathy can develop in patients with trauma, during obstetric complications, and during major surgery as a result of excessive blood loss and subsequent consumption of coagulation factors as well as hemodilution. In addition, an increasing number of patients receive anticoagulants and antiplatelet drugs preoperatively that might influence the response to surgical hemostasis. This review focuses on those situations that may change normal hemostasis and coagulation during surgery, producing both hyperfibrinolysis and hypofibrinolysis, such as overcorrection with coagulation factors, bleeding and hyperfibrinolysis that may occur with extracorporeal circulation and high aortic-portal-vena cava clamps, and hyperfibrinolysis related to severe maintained hemodynamic disturbances. We also evaluate the role of tranexamic acid for prophylaxis and treatment in different surgical settings, and finally the value of point-of-care testing in the operating room is commented with regard to investigation of fibrinolysis.

Outcome of Major Hemorrhage at a Major Cardiothoracic Center in Patients with Activated Major Hemorrhage Protocol versus Nonactivated Protocol

This study aimed to determine the impact of major hemorrhage (MH) protocol (MHP) activation on blood administration and patient outcome at a UK major cardiothoracic center. MH was defined in patients (> 16 years) as those who received > 5 units of red blood cells (RBCs) in < 4 hours, or > 10 units in 24 hours. Data were collected retrospectively from patient electronic records and hospital transfusion databases recording issue of blood products from January 2016 to December 2018. Of 134 patients with MH, 24 had activated MHP and 110 did not have activated MHP. Groups were similar for age, sex, baseline hemoglobin, platelet count, coagulation screen, and renal function with no difference in the baseline clinical characteristics. The total number of red cell units (median and [IQR]) transfused was no different in the patients with activated (7.5 [5-11.75]) versus nonactivated (9 [6-12]) MHP (p = 0.35). Patients in the nonactivated MHP group received significantly higher number of platelet units (median: 3 vs. 2, p = 0.014), plasma (median: 4.5 vs. 1.5, p = 0.0007), and cryoprecipitate (median: 2 vs. 1, p = 0.008). However, activation of MHP was associated with higher mortality at 24 hours compared with patients with nonactivation of MHP (33.3 vs. 10.9%, p = 0.005) and 30 days (58.3 vs. 30.9%, p = 0.01). The total RBC and platelet (but not fresh frozen plasma [FFP]) units received were higher in deceased patients than in survivors. Increased mortality was associated with a higher RBC:FFP ratio. Only 26% of patients received tranexamic acid and these patients had higher mortality at 30 days but not at 24 hours. Deceased patients at 30 days had higher levels of fibrinogen than those who survived (median: 2.4 vs. 1.8, p = 0.01). Patients with activated MHP had significantly higher mortality at both 24 hours and 30 days despite lack of difference in the baseline characteristics of the patients with activated MHP versus nonactivated MHP groups. The increased mortality associated with a higher RBC:FFP ratio suggests dilutional coagulopathy may contribute to mortality, but higher fibrinogen at baseline was not protective.

Evaluation of Automated Delivery of Propofol Using a Closed-Loop Anesthesia Delivery System in Patients Undergoing Thoracic Surgery: A Randomized Controlled Study

OBJECTIVE

Automated propofol total intravenous anesthesia (TIVA) administered by a closed-loop anesthesia delivery system (CLADS) exhibits greater efficiency than conventional manual methods, but its use in major thoracic surgery is limited.

DESIGN

Prospective, single-blind, randomized controlled study.

SETTING

Single-center tertiary care hospital.

PARTICIPANTS

Patients undergoing thoracic surgery.

INTERVENTIONS

Patients were randomly allocated to receive CLADS-driven (CLADS group) or manually controlled (manual group) propofol TIVA.

MEASUREMENTS AND MAIN RESULTS

Anesthesia depth consistency (primary objective) and anesthesia delivery performance, propofol usage, work ergonomics, intraoperative hemodynamics, and recovery profile (secondary objectives) were analyzed. No differences were found for anesthesia depth consistency (percentage of time the bispectral index was within ± 10 of target) (CLADS group: 82.5% [78.5%-87.2%] v manual group: 86.5% [74.2%-92.5%]; p = 0.581) and delivery performance, including median performance error (CLADS group: 3 [-4 to 6] v manual group: 1 [-2.5 to 6]); median absolute performance error (CLADS group: 10 [10-12] v manual group:10 [8-12]); wobble (CLADS group: 10 [8-12] v manual group: 9 [6-10.5]); and global score (CLADS group: 24.2 [21.2-29.3] v manual group: 22.1 [17.3-32.3]) (p > 0.05). However, propofol requirements were significantly lower in the CLADS group for induction (CLADS group: 1.27 ± 0.21] mg/kg v manual group: 1.78 ± 0.51 mg/kg; p = 0.014) and maintenance (CLADS group: 4.02 ± 0.99 mg/kg/h v manual group: 5.11 ± 1.40 mg/kg/h; p = 0.025) of TIVA. Ergonomically, CLADS-driven TIVA was found to be significantly superior to manual control (infusion adjustment frequency/h) (manual infusion: 9.6 [7.8-14.9] v CLADS delivery [none]).

CONCLUSIONS

In thoracic surgery patients, CLADS-automated propofol TIVA confers significant ergonomic advantage along with lower propofol usage.

Effects of a targeted blood management programme on allogeneic blood transfusion in abdominal aortic aneurysm surgery

OBJECTIVES

To investigate the impact of a dedicated cell salvage practitioner team on blood loss and allogeneic transfusion in abdominal aortic aneurysm (AAA) surgery.

BACKGROUND

Cell salvage reduces allogeneic transfusion in AAA surgery, but is commonly performed by the anaesthetic nurse. At our hospital, a dedicated patient blood management practitioner is present for all elective open AAA repairs.

METHODS/MATERIALS

Data were collected on 171 AAA patients operated on at the John Radcliffe Hospital, Oxford over a 3-year period, looking at the Patient Blood Management processes, including: blood loss, cell salvage, near-patient testing (thrombelastography) and transfusion rates of allogeneic blood products.

RESULTS

Blood loss ranged from 3-108% of estimated blood volume (EBV) (median 25% = 1500 mL). In seven patients who lost 70-110% of their EBV, none reached the thrombelastography intervention threshold for R time (11 min) or MA (48 mm) despite such massive blood loss. Overall, only 7/171 (4%) patients received intra-operative allogeneic blood, all of whom had a mean baseline haemoglobin concentration < 106 g L^-1 (median 98, range 95-105 g L^-1 ). In terms of other blood products, only 4/171 (2·3%) received one unit of platelets each intra-operatively. None received FFP or cryoprecipitate.

CONCLUSIONS

Such low levels of allogeneic transfusion have not been reported previously. We hypothesise that this is due to the additional blood management contributions of the specialised cell salvage practitioners and collaboration with the rest of the vascular surgical team. These results support the development of pre-operative anaemia clinics. Overall the service runs at a profit to the trust.

Early postoperative blood pressure and blood loss after cardiac surgery: A retrospective analysis

BACKGROUND

Increased blood loss after cardiac surgery is a risk factor for patient morbidity and mortality. Guidelines for postoperative haemodynamics management recommend normotensive blood pressure to avoid increased chest drain volumes. The aim of this study was to verify the correlation of early postoperative hypertension and blood loss in patients after cardiac surgery during the early postoperative period.

METHODS

Postoperative mean blood pressure values and chest drain volumes of 431 patients were registered by an intensive care monitoring system during first 60minutes after intensive care admission. Correlation between blood pressure and blood loss was calculated by linear regression analysis.

RESULTS

In the entire patient cohort and in various subgroup analyses (body-mass-index, type of surgery, comorbidity, emergency surgery, preoperative anticoagulation therapy) no association between early mean blood pressure >80mmHg and increased blood loss was evident in simple regression analysis. Merely, after aortic surgery a correlation of hypertension and blood loss was found. Multiple regression revealed postoperative INR values >1.5 and thrombocyte counts <100.000/nL to impact blood loss in contrast to postoperative hypertension.

CONCLUSION

Evidence for strict blood pressure management to reduce blood loss after cardiac surgery is scarce. Instead, in face of higher INR and low thrombocytes increasing postoperative blood loss, achieving and maintaining a physiological coagulation is essential.