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Background: Healthcare systems face challenges in optimizing resources while maintaining high-quality care. Breast cancer surgery represents a substantial share of elective surgery and provides an opportunity to evaluate different organizational models. This study presents a health economic analysis comparing two models for breast cancer surgery at the same hospital.

Methods: A bottom-up micro-costing approach was employed to evaluate potential cost-savings of breast cancer surgeries performed at a general surgical department (GS) versus a cardiothoracic surgery department (CT). We analyzed 543 consecutive patients undergoing elective breast cancer surgery between January 2014 and September 2016. Resource use was identified through direct observation, hospital administrative systems, and operating room logs. Personnel, disposables, medications, and facility costs were quantified based on observed resource use within the study dataset; no external benchmarking was performed.

Results: CT was less expensive, with an average saving of 3,547 Swedish krona (SEK) per operation (95% CI: -674 to 7,510 SEK). Bootstrap analysis with 1,000 iterations showed CT was less costly in 96.2% of samples. Procedures were shorter at CT (170.8 vs. 221.3 min), enabling more operations per day (3.2 vs. 2.4). In our deterministic simulation, removing CT capacity increased waiting times by 15%, from 39 to 45.1 days, conditional on steady inflow and constant OR availability. Annual savings at the observed annual volume (~ 192 patients) were 681,104 SEK and could reach ~ 1.77 million SEK if volumes increased to 500 patients/year.

Conclusions: The CT organizational model was more likely to be less costly while maintaining shorter waiting times. These findings suggest that CT capacity may be prioritized, particularly at higher patient volumes, to support both economic efficiency and patient access.

Background: Delirium is a common neurological complication after cardiac surgery. The purpose of the present study was to analyze the association between hemodynamic fluctuations during cardiopulmonary bypass (CPB) and the incidence of postoperative delirium (POD) in patients undergoing cardiac surgery with CPB.

Methods: This post hoc analysis included one-hundred-ninety-five (n = 195) patients aged ≥ 65 years of whom seventy (n = 70) patients developed POD. Intraoperative hemodynamic variables specifically related to the conduct of CPB were digitally recorded at 1-minute intervals. Variables outside the presumed safe boundaries for mean arterial pressure (MAP), systemic perfusion flow index– L/min/BSA (QBSA_I), systemic venous oxygen saturation (S_VO₂) and arterial oxygen delivery– ml/min/BSA (DO₂) were defined and analyzed with reference to indices of area under the curve (AUC) and the relative proportion of registrations related to POD. POD was diagnosed according to DSM-5 criteria based on a test battery performed preoperatively and repeated twice postoperatively. Statistical tests used to verify observations outside the predefined norm included the Mann-Whitney U test and the chi-squared test.

Results: Markers of hemodynamic control during CPB showed significant associations with POD. Both DO₂ (P = 0.02) and QBSA_I (P < 0.001) identified POD patients outside the predefined upper and lower safety limits. S_VO₂ values > 84% (P < 0.001) werealso associated with the development of POD. The number of S_VO₂ registrations below the lower safety limit was negligible, why statistical analysis seemed not useful. No association between MAP and POD registrations was identified.

Conclusions: This study revealed a clear association between markers of hemodynamic control and POD. These associations were most pronounced for DO₂ and QBSA_I. The detected association between high S_VO₂ and POD warrants further insight.

Selective antegrade cerebral perfusion (SACP) is a protective procedure to ascertain adequate brain perfusion during aortic arch surgeries requiring moderate hypothermic circulatory arrest. SACP entails catheterization of arteries feeding the brain, which can be done bilaterally (bSACP) or unilaterally (uSACP), but there is no consensus on when to use each approach. bSACP may increase the risk of embolization, while uSACP risks hypoperfusion due to insufficient perfusion pressure in the contralateral hemisphere, since a single catheter must perfuse both hemispheres. We developed and tested the feasibility of a new method for predicting cerebral perfusion pressures (CPP) during SACP, which could potentially aid clinicians in preoperatively identifying which SACP approach to use. Feasibility of the method was evaluated in five patients eligible for aortic arch surgery (65 ± 7 years, 3 men). Patients were investigated preoperatively with computed tomography angiography (CTA) and 4D flow magnetic resonance imaging (MRI) to assess patient-specific arterial anatomy and blood flows. From the imaging, computational fluid dynamics (CFD) simulations estimated the patients' vascular resistances. Applying these resistances and intraoperative SACP pressure/flow settings to the model's boundary conditions allowed for predictions of contralateral CPP during SACP. Predicted pressures were compared to corresponding intraoperative pressure measurements. The method showed promise for predicting contralateral CPP during both uSACP (median error (range): 2.4 (−0.2–18.0) mmHg) and bSACP (0.8 (−3.3–5.4) mmHg). Predictions were most sensitive to collateral artery size. This study showed the feasibility of CPP predictions of SACP, and presents key features needed for accurate modelling.

Introduction: The study objective was to investigate whether a Ringer’s acetate based priming solution with addition of Mannitol and sodium concentrate increases the risk of cardiac surgery associated kidney injury (CSA-AKI).

Methods: This is a double blind, prospective randomized controlled trial from a single tertiary teaching hospital in Sweden including patients aged ≥65 years (n = 195) admitted for routine cardiac surgery with cardiopulmonary bypass. Patients in the study group received Ringer’s acetate 1000 mL + 400 mL Mannitol (60 g) + sodium chloride 40 mL (160 mmol) and heparin 2 mL (10 000 IU) 966 mOsmol (n = 98), while patients in the control group received Ringer’s acetate 1400 mL + heparin 2 mL (10 000 IU), 388 mOsmol (n = 97) as pump prime. Acute kidney injury was analysed based on the Kidney Disease Improving Outcomes (KDIGO 1-3) definition.

Results: The overall incidence of CSA-AKI (KDIGO stage 1) was 2.6% on day 1 in the ICU and 5.6% on day 3, postoperatively. The serum creatinine level did not show any postoperative intergroup differences, when compared to baseline preoperative values. Six patients in the Ringer and five patients in the Mannitol group developed CSA-AKI (KDIGO 1-3), all with glomerular filtration rates <60 mL/min/1.73 m2. These patients showed significantly higher plasma osmolality levels compared to preoperative values. Hyperosmolality together with patient age and the duration of the surgery were independent risk factors for postoperative acute kidney injury (KDIGO 1-3).

Conclusions: The use of a hyperosmolar prime solution did not increase the incidence of postoperative CSA-AKI in this study, while high plasma osmolality alone increased the associated risk by 30%. The data suggests further examination of plasma hyperosmolality as a relative risk factor of CSA-AKI.

Objective: Postoperative delirium (POD) is common after cardiac surgery. We have previously identified plasma sodium concentration and the volume of infused fluids during surgery as possible risk factors. Both are linked to the selection and composition of the pump prime used for cardiopulmonary bypass (CPB). Present study aims to examine whether hyperosmolality increases the risk for POD.

Design: Patients ≥65 years (n = 195) scheduled for cardiac surgery were prospectively enrolled into this double blinded randomised clinical trial. Study group received a pump prime containing mannitol and ringer-acetate (966 mOsmol) (n = 98) vs. ringer-acetate (388 mOsmol) (n = 97) in the control group. Postoperative delirium was defined according to DSM-5 criteria based on a test-battery pre- and postoperatively (days 1–3). Plasma osmolality was measured on five occasions and coordinated with the POD assessments. The primary outcome was the POD incidence related to hyperosmolality as the secondary outcome.

Results: The incidence of POD was 36% in the study group and 34% in the control group, without intergroup difference (p=.59). The plasma osmolality was significantly higher in the study group, both on days 1 and 3 and after CPB (p<.001). Post hoc analysis indicated that high osmolality levels increased the risk for delirium on day 1 by 9% (odds ratio (OR) 1.09, 95% CI 1.03–1.15) and by 10% on day 3 (OR 1.10, 95% CI 1.04–1.16).

Conclusions: Use of a prime solution with high osmolality did not increase the incidence of POD. However, the influence of hyperosmolality as a risk factor for POD warrants further investigation.

BACKGROUND: Cerebral blood flow (CBF) is believed to be relatively constant within an upper and lower blood pressure limit. Different methods are available to monitor CBF autoregulation during surgery. This study aims to critically analyze the application of the cerebral oxygenation index (COx), one of the commonly used techniques, using a reference to data from a series of clinical registrations.

METHOD: CBF was monitored using near-infrared spectroscopy, while cerebral blood pressure was estimated by recordings obtained from either the radial or femoral artery in 10 patients undergoing cardiopulmonary bypass. The association between CBF and blood pressure was calculated as a moving continuous correlation coefficient. A COx index > 0.4 was regarded as a sign of abnormal cerebral autoregulation (CA). Recordings were examined to discuss reliability measures and clinical feasibility of the measurements, followed by interpretation of individual results, identification of possible pitfalls, and suggestions of alternative methods.

RESULTS AND CONCLUSION: Monitoring of CA during cardiopulmonary bypass is intriguing and complex. A series of challenges and limitations should be considered before introducing this method into clinical practice.

Background: Responsible and efficient resource utilization are important factors in healthcare. The aim of this study was to investigate how total case time differs between two differently organized surgical departments. Methods: This is a retrospective observational study of a cohort of patients undergoing elective surgery for breast cancer or malignant melanoma in a university hospital setting in Sweden. All patients were operated on by the same set of surgeons but in two different surgical departments: a general surgery (GS) and a cardiothoracic (CT) surgery department. Patients were selected to the two departments from a waiting list in the order of referral for surgery. The effect of being operated on at the CT department compared to the GS department was estimated by linear regression. Results: The final study cohort comprised 349 patients in the GS department and 177 patients in the CT department. Both groups were similar regarding surgical procedures, American Society of Anesthesiologists' score, body mass index, age, sex, and the skill level of the operating surgeon. These covariates were included in the linear regression model. The total case time, defined by the Procedural Time Glossary as room set-up start to room clean-up finish, was significantly shorter for the patients who underwent a surgical procedure at the CT department compared to the GS department, even after adjusting for the background characteristics of the patients and surgeon. After adjusting for the selected covariates, the average difference in total case time between the two departments was − 30.67 min (p = 0.001). Conclusions: A significantly shorter total case time was measured for operations in the CT department. Plausible explanations may be more beneficial organizational factors, such as staffing ratio, skill mix in the operating room team, and working behavioral aspects regarding resource utilization.

The sensitivity to heparin during cardiopulmonary bypass (CPB) is determined by patient-specific characteristics and is assessed by the whole blood activated clotting time (ACT). We aimed to examine reliability measures between two different ACT monitors using Bland-Altman analysis: bias should not exceed 50 ± 50 seconds for measurements performed during CPB or 10 ± 10 seconds before and after CPB. The ACT response should be linear in relation to the concentration of heparin in plasma. Twenty patients (n = 20) aged 20-80 years and admitted for coronary artery bypass surgery were enrolled to this clinical observational study. ACT values and antifactor Xa were sampled: 1) before induction of anesthesia, 2) after heparin bolus, 3) during CPB at the start of rewarming, 4) at weaning from CPB, and 5) after heparin reversal. The evaluation comprised the Hemostasis Management System Plus™ (HMS, Medtronic Inc., Minneapolis, MN) and i-STAT™ (Abbott, Point of Care Inc., Princeton, NJ). Bias for the HMS Plus™ vs. i-STAT™ was +105 ± 119 seconds for measurements during CPB and +2.8 ± 11.7 seconds before and after CPB. Associated limits of agreement for the observed bias were ±235 and ±23 seconds, respectively. Inter-device correlation of ACT values was .46 (p < .001) during CPB; otherwise .48 (p = .02). Both devices produced ACT values unrelated (<10%) to the measured heparin concentration. The use of multivariable regression analysis demonstrated an independent association between the ACT measurement and hematocrit, however, not with the plasma concentration of heparin. ACT monitors demonstrate unacceptable bias differences, combined with wide limits of agreement. The ACT response correlated with hematocrit, but not with the actual heparin concentration.

Background: Patients with preoperative dual antiplatelet therapy prior to coronary artery bypass surgery are at risk of bleeding and blood component transfusion. We hypothesise that an optimised cardiopulmonary bypass strategy reduces postoperative blood loss and transfusions.

Methods: In total, 60 patients admitted for coronary artery bypass grafting with ticagrelor and aspirin medication withdrawn <96 hours before surgery were prospectively randomised into two equal sized groups. Cardiopulmonary bypass combined a closed Cortiva (R) heparin-coated circuit with low systemic heparinisation (activated clotting time < 250 seconds) and intraoperative cell salvage in the study group, whereas the control group used a Balance (R) coated open circuit, full systemic heparinisation (activated clotting time > 480 seconds) and conventional cardiotomy suction. This perfusion strategy was evaluated by the chest drain volume after 24 hours, perioperative haemoglobin and platelet loss accompanied by global coagulation assessments.

Results: Patients in the study group demonstrated significantly better outcomes signified by lower blood loss 554 +/- 224 versus 1,100 +/- 989 mL (p < 0.001), reduced packed red cell transfusion 7% versus 53% (p < 0.001), reduced haemoglobin -28 +/- 15 versus -40 +/- 14 g/L (p = 0.004) and platelet loss -35 +/- 36 versus -82 +/- 67 x 10(9)/L (p = 0.001). Indices of rotational thromboelastometry indicated shorter clotting times within the internal and external pathways. Adenosine diphosphate activated platelet function was within normal range based on Multiplate (R) aggregometry, while ROTEM (R) platelet analyses indicated inhibited function both preoperatively and post-bypass. Platelet inhibition by aspirin was verified throughout the perioperative period. Platelet function showed no intergroup differences.

Conclusion: A stringent perfusion strategy reduced blood loss and transfusions in dual antiplatelet therapy patients requiring urgent surgery.