Sam Eriksson

Increased C1q, C4 and C3 deposition on platelets in patients with systemic lupus erythematosus - a possible link to venous thrombosis?

Objective: Patients with systemic lupus erythematosus (SLE) have an increased risk of developing vascular diseases (VD) such as myocardial infarction, stroke and venous thrombosis, which can only partly be explained by traditional risk factors. The role of platelets in this process has not been extensively studied. Platelet activation supports complement binding to the platelet surface, and increased C4d has been seen on platelets in SLE patients as well as in non-rheumatic patients with stroke. In this study we investigated in vivo platelet deposition of the classical complement pathway components C1q, C4d and C3d in relation to VD in SLE patients. Furthermore, the ability of serum to support in vitro complement deposition on fixed heterologous platelets was analyzed. Methods: Blood from 69 SLE patients and age- and sex-matched healthy individuals was collected in sodium-citrate tubes and platelets isolated by centrifugation. Complement deposition on platelets was detected by flow cytometry. Results: We could demonstrate that SLE patients had increased C1q, C3d and C4d deposition on platelets as compared to healthy controls (p < 0.0001). SLE patients with a history of venous thrombosis had increased complement deposition on platelets as compared to SLE patients without this manifestation (p < 0.05). In vitro studies demonstrated that serum from patients with lupus anticoagulant, venous thrombosis or antiphospholipid antibody syndrome supported increased platelet C4d deposition in vitro as compared to SLE patients without these manifestations (p < 0.05). Our data support the hypothesis that platelet activation and the subsequent complement deposition on platelets are central in the development of venous thrombosis in SLE. Conclusions: Altogether we suggest that complement deposition on platelets could reflect important pathogenetic events related to the development of venous thrombosis in SLE and might be used as a marker for venous thrombosis in SLE.

Non-invasive imaging of microcirculation: a technology review.

Microcirculation plays a crucial role in physiological processes of tissue oxygenation and nutritional exchange. Measurement of microcirculation can be applied on many organs in various pathologies. In this paper we aim to review the technique of non-invasive methods for imaging of the microcirculation. Methods covered are: videomicroscopy techniques, laser Doppler perfusion imaging, and laser speckle contrast imaging. Videomicroscopy techniques, such as orthogonal polarization spectral imaging and sidestream dark-field imaging, provide a plentitude of information and offer direct visualization of the microcirculation but have the major drawback that they may give pressure artifacts. Both laser Doppler perfusion imaging and laser speckle contrast imaging allow non-contact measurements but have the disadvantage of their sensitivity to motion artifacts and that they are confined to relative measurement comparisons. Ideal would be a non-contact videomicroscopy method with fully automatic analysis software.

Limiting factors for liver regeneration after a major hepatic resection for colorectal cancer metastases.

BACKGROUND Chemotherapy before resection of colorectal metastases in the liver is extensively used and has been shown to induce histopathological changes in the liver parenchyma, although little is known about the effect of chemotherapy on liver regeneration. The aim of this study was to determine if pre-operative chemotherapy influences the regenerated liver volume after a major liver resection. PATIENTS AND METHODS This retrospective cohort study included 74 patients subjected to a major liver resection for colorectal metastases. Patients were divided into two groups depending on whether they had been treated with chemotherapy less than 3 months before surgery or not. Liver volumes were measured before and 1 year after resection. RESULTS Pre-operative chemotherapy reduced volumetric liver regeneration (83 ± 2% versus 91 ± 2%; P = 0.007) as compared with patients without chemotherapy. There was a linear correlation between regenerated volume and time interval between the end of chemotherapy to resection (P = 0.031). CONCLUSIONS Pre-operative chemotherapy in patients with colorectal liver metastases negatively affects volume regeneration after a partial hepatectomy. The time interval between chemotherapy and surgery determines the impact of these affects.

Microcirculation changes during liver resection — A clinical study

BACKGROUND In this study we aimed to evaluate effects of liver resection on hepatic microcirculation. In addition we wanted to study if histological liver damage could be detected intra-operatively. PATIENTS AND METHODS 40 patients undergoing hepatic resection were included and grouped according to if they were operated with a major or minor resection. Hepatic microcirculation measurements were made intra-operatively before and after liver resection with sidestream dark-field (SDF) imaging. Red blood cell velocity (RBCV), sinusoidal diameter and functional sinusoidal density were determined. RESULTS After hepatic resection RBCV increased in both the minor and major groups (44 μm/s, P=0.016 and 121 μm/s, P=0.002). RBCV in patients with histological damages was 225 (148-464) μm/s vs. 161 (118-329) μm/s in patients with no damage (P=0.016). CONCLUSION A hepatic resection leads to an increase of sinusoidal RBCV. SDF imaging could potentially be used to intraoperatively identify histological damages.

Laser speckle contrast imaging for intraoperative assessment of liver microcirculation: a clinical pilot study.

Background Liver microcirculation can be affected by a wide variety of causes relevant to liver transplantation and resectional surgery. Intraoperative assessment of the microcirculation could possibly predict postoperative outcome. The present pilot study introduces laser speckle contrast imaging (LSCI) as a new clinical method for assessing liver microcirculation. Methods LSCI measurements of liver microcirculation were performed on ten patients undergoing liver resection. Measurements were made during apnea with and without liver blood inflow occlusion. Hepatic blood flow was assessed by subtracting zero inflow signal from the total signal. Zero inflow signal was obtained after hepatic artery and portal vein occlusion. Perfusion was expressed in laser speckle perfusion units, and intraindividual and interindividual variability in liver perfusion was investigated using the coefficient of variability. Results Hepatic microcirculation measurements were successfully made in all patients resulting in analyzable speckle contrast images. Mean hepatic blood flow was 410±36 laser speckle perfusion units. Zero inflow signal amounted to 40%±4% of the total signal. Intraindividual and interindividual coefficients of variability in liver perfusion were 25% and 28%, respectively. Conclusion Under the conditions of this pilot study, LSCI allows rapid noncontact measurements of hepatic blood perfusion over wide areas. More studies are needed on methods of handling movement artifacts.

Concurrent biliary drainage and portal vein embolization in preparation for extended hepatectomy in patients with biliary cancer.

Background Patients with perihilar cholangiocarcinoma and gallbladder cancer extending into the hilum often present with jaundice and a small future liver remnant (FLR). If resectable, preoperative biliary drainage and portal vein embolization (PVE) are indicated. Classically, these measures have been performed sequentially, separated by 4–6 weeks. Purpose To report on a new regime where percutaneous transhepatic biliary drainage (PTBD) and PVE are performed simultaneously, shortening the preoperative process. Material and Methods Six patients were treated with concurrent PTBD and PVE under general anesthesia. Results Surgical exploration followed the combined procedure after 35 days (range, 28–51 days). The FLR ratio increased from 22% to 32%. Three patients developed cholangitis after the procedure. Conclusion The combined approach of PTBD and PVE seems feasible, but more studies on morbidity are warranted.

Significance of poor performance status after resection of colorectal liver metastases

BackgroundPerformance status (PS) is known as one of the strongest prognostic factors for survival in metastatic colorectal cancer patients. The aim of the present study was to analyze factors associated with poor PS assessed after resection for colorectal liver metastases and the impact on survival.MethodsAll patients undergoing curative resection for colorectal liver metastases between 2010 and 2015 in a single center were reviewed retrospectively.ResultsA total of 284 patients were included, out of whom 74 patients (26%) presented with a postoperative PS WHO > 2 precluding administration of adjuvant chemotherapy. These patients had a shorter recurrence-free survival (P = 0.002) and shorter overall survival (P < 0.001). Multivariable analysis showed that patients with PS > 2 after surgery had higher preoperative ASA score, had a higher frequency of major complications after surgery, and had more frequently synchronous liver and lung metastases. PS was found to be the strongest independent factor predicting survival (hazard ratio 0.45). When patients with postoperative PS > 2 developed recurrent disease (54 of 74), 43 (80%) received tumor specific treatment.ConclusionsPatients with postoperative PS > 2 who did not receive adjuvant chemotherapy had decreased recurrence-free and overall survival after liver resection for colorectal liver metastases. After recurrence, a large majority of these patients had had improvement in PS allowing for administration of tumor specific treatment.

Perioperative liver and spleen elastography in patients without chronic liver disease

AIM To investigate changes in hepatic and splenic stiffness in patients without chronic liver disease during liver resection for hepatic tumors. METHODS Patients scheduled for liver resection for hepatic tumors were considered for enrollment. Tissue stiffness measurements on liver and spleen were conducted before and two days after liver resection using point shear-wave elastography. Histological analysis of the resected liver specimen was conducted in all patients and patients with marked liver fibrosis were excluded from further study analysis. Patients were divided into groups depending on size of resection and whether they had received preoperative chemotherapy or not. The relation between tissue stiffness and postoperative biochemistry was investigated. RESULTS Results are presented as median (interquartile range). 35 patients were included. The liver stiffness increased in patients undergoing a major resection from 1.41 (1.24-1.63) m/s to 2.20 (1.72-2.44) m/s (P = 0.001). No change in liver stiffness in patients undergoing a minor resection was found [1.31 (1.15-1.52) m/s vs 1.37 (1.12-1.77) m/s, P = 0.438]. A major resection resulted in a 16% (7%-33%) increase in spleen stiffness, more (P = 0.047) than after a minor resection [2 (-1-13) %]. Patients who underwent preoperative chemotherapy (n = 20) did not differ from others in preoperative right liver lobe [1.31 (1.16-1.50) vs 1.38 (1.12-1.56) m/s, P = 0.569] or spleen [2.79 (2.33-3.11) vs 2.71 (2.37-2.86) m/s, P = 0.515] stiffness. Remnant liver stiffness on the second postoperative day did not show strong correlations with maximum postoperative increase in bilirubin (R2 = 0.154, Pearson’s r = 0.392, P = 0.032) and international normalized ratio (R2 = 0.285, Pearson’s r = 0.534, P = 0.003). CONCLUSION Liver and spleen stiffness increase after a major liver resection for hepatic tumors in patients without chronic liver disease.