Cerebral Oxygenation Changes Observed In Patients Undergoing Spinal Neurosurgery in Prone Position Using Near Infrared Spectroscopy

Near infrared spectroscopy (NIRS) devices like cerebral oximeters have lately gained their actuality in different fields of medicine. Used intraoperative they can early detect harmful event and gives a possibility to avoid from further brain damage. The goal of study was to determine whether prone position during spinal neurosurgery impacts cerebral oxygen saturation using NIRS.publishersversionPeer reviewe

Regional cerebral oxygen saturation monitoring during spinal surgery in order to identify patients at risk for cerebral desaturation

Publisher Copyright: © 2020 by the authors. Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Near infrared spectroscopy (NIRS) devices are non-invasive and monitor cerebral oxygen saturation (rScO2) continuously. NIRS interventional protocol is available in order to avoid hypoxic brain injury. Methods: We recruited patients scheduled for spinal surgery (n = 44). rScO2 was monitored throughout the surgery using INVOS 4100 cerebral oximeter. If the rScO2 values dropped more than 20% below baseline, or there was an absolute drop to below 50%, NIRS interventional protocol was followed. Results: In two patients rScO2 decreased by more than 20% from baseline values. In one patient rScO2 decreased to below 50%. NIRS protocol was initiated. As the first step, correct head position was verified-in one patient rScO2 increased above the threshold value. In the two remaining patients, mean arterial pressure was raised by injecting Ephedrin boluses as the next step. rScO2 raised above threshold. Patients with desaturation episodes had longer medium time of the operation (114 ± 35 versus 200 ± 98 min, p = 0.01). Pearson's correlation showed a negative correlation between rScO2 and duration of operation (r = 0.9, p = 0.2). Receiver operating characteristic curve analysis showed blood loss to be a strong predictor for possible cerebral desaturation (Area under the curve (AUC): 0.947, 95%CI: 0.836-1.000, p = 0.04). Conclusion: Patients with higher blood loss might experience cerebral desaturation more often than spinal surgery patients without significant blood loss.publishersversionPeer reviewe

Potential effect of two different anaesthesia techniques on the activation of hhv-6 and hhv-7 infection in relation to changes in total lymphocyte count and peripheral immune cell distribution after prolonged microvascular free flap surgery

Copyright: Copyright 2015 Elsevier B.V., All rights reserved.Microvascular free flap surgery is a complex method of wound closure for large wounds. Tissue trauma, surgical stress and general anaesthesia are known immunosuppressors that may exacerbate postoperative infections. Beta-herpesviruses HHV-6 and HHV-7 are immunomodulating viruses highly prevalent in the population of healthy individuals, which can interfere with the function of the host immune system. These viruses can be reactivated in immunosuppressed conditions. The aim of this study was to monitor the potential effects of two different anaesthesia techniques - general anaesthesia (GA) and regional anaesthesia (RA) - on the activation of HHV-6 and HHV-7 infection in relation to changes in the total lymphocyte count and peripheral immune cell distribution after microvascular free flap surgery. We found significant increase in the frequency of active HHV-7 infection after surgery (p < 0.05) in the GA group. In the RA group changes were not significant. The activation of HHV-7 infection was associated with decrease in the total lymphocyte count post-operatively in patients from the GA group. The data of our study show that reconstructive flap surgery under GA is linked with more frequent postoperative lymphopenia, which is a potential post-operative immunosuppressor that probably triggers the activation of HHV-6 and HHV-7 infection.Peer reviewe

Inherited thrombophilias in thrombosis advancement in microvascular flap surgery

Publisher Copyright: © 2021 Proceedings of the Latvian Academy of Sciences. Section B. Natural, Exact, and Applied Sciences. All right reserved.Microvascular flap surgery is a reliable method for reconstructive surgery. To avoid and foresee free flap thrombosis advancement after microvascular flap surgery, patient assessment, flawless surgical technique, and eligible perioperative care are pivotal. In this prospective observational study, we aimed to elucidate the most common inherited single nucleotide polymorphisms (SNPs) attributable to free flap thrombosis. A total of 152 patients undergoing microvascular flap surgery during the study period of 2016–2019 were analysed for five SNPs: rs6025 in Factor V Leiden (FVL) gene, rs1799963 in Factor II (FII) gene, rs2066865 in Fibrinogen Gamma Chain gene (FGG), rs2227589 in SERPINC 1 gene and rs1801133 in Methylene Tetrahydrofolate Reductase (MTHFR) gene. Activated protein C resistance (aPCR), prothrombin, antithrombin (AT), fibrinogen and homocysteine plasma levels were measured to determine association with the analysed SNPs and with free flap thrombosis advancement. Our preliminary results show that carriers of FVL mutation were associated with aPCR, as we observed significantly lower aPCR plasma levels in carriers of genotype C/T, as compared to C/C; p = 0.006 (CI 95%, 0.44 to 1.19). Additionally, mean fibrinogen plasma levels were higher in carriers of FGC gene rs2066865 genotype A/A (5.6 ± 1.81 g/l), as compared to G/A and G/G; p = 0.04 (CI 95%, 0.007 to 1.09); p = 0.004 (CI 95%, 0.48 to 2.49), respectively. The study group included 12 patients (7.9%) with free flap thrombosis. For one patient free flap thrombosis advancement might have been related to the rs6025T – FVL mutation with a PCR plasma level 1.21. Lower aPCR levels was associated with carriers of FVL rs6025 C/T and higher fibrinogen plasma levels with carriers of FGG rs2066865 A/A, suggesting that these genotypes might predict higher free flap thrombosis risk, but we found no significant association between analysed SNPs and free flap thrombosis advancement.publishersversionPeer reviewe

Leukocytosis and C-Reactive Protein May Predict Development of Secondary Cerebral Vasospasm in Patients with Aneurysmal Subarachnoid Hemorrhage

Publisher Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland.Background and Objectives: Secondary cerebral vasospasm (CV) with subsequent delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage (aSAH) remains an unpredictable pathology. The aim of this retrospective study was to investigate the association between inflammatory parameters, white blood cell (WBC) count, and C-reactive protein plasma levels (CRP) and the occurrence of secondary CV in patients with aSAH. Materials and Methods: The medical records of 201 Intensive Care Unit patients in Riga East University Hospital with aSAH were retrospectively reviewed in a 24-month period. WBC count and CRP values were observed at admission to the hospital and on the third day. According to the inclusion criteria, 117 (48 males) participants were enrolled for further analysis, with average age of 56 ± 15 years (mean ± SD). In total, secondary CV was diagnosed in 21.4% of cases, and DCI in 22.4% of cases. The patients were classified into three groups: SAH-CV group (n = 25), SAH-DCI group (n = 12), and SAH or control group (n = 80), for comparative analysis. Results: We found that SAH-CV patients demonstrated notably higher inflammatory parameters compared to controls: WBC 13.2 ± 3.3 × 109 /L vs. 11.2 ± 3.7 × 109 /L; p = 0.01 and CRP median 9.3 mg/L vs. 1.9 mg/L; p <0.001, respectively. We found that the odds of developing CV increased by 5% for each CRP increase of 1 mg/L at admission (OR, 1.05; CI, 1.014–1.087; p = 0.006). Concomitantly, the odds increased by 16% for every rise in WBC count of 1 × 109 /L (OR, 1.16; CI, 1.02–1.32; p = 0.02). WBC count was associated with the occurrence of CV with 96% sensitivity and 40% specificity, with a cut off level of 10.015 × 109 /L and AUC 0.683; p = 0.006. CRP displayed 54% sensitivity and 90% specificity with a cut off value of 8.9 mg/L and AUC 0.751; p < 0.001. Moreover, higher values of inflammatory parameters at admission correlated with a longer stay in ICU (r = 0.3, p = 0.002 for WBC count and r = 0.305, p = 0.002 for CRP values), and poor outcome (death) was significantly associated with higher CRP values at admission and on the third day (16.1. vs. 2.2. and 57.4. vs. 11.1, p < 0.001, respectively). Higher mortality was detected in SAH-CV patients (32%) compared to controls (6.3%; p < 0.001). Conclusions: Inflammatory parameters such as WBC count and CRP values at admission might be helpful to predict the development of secondary CV.publishersversionPeer reviewe

Polymorphism rs2066865 in the Fibrinogen Gamma chain (FGG) gene increases plasma fibrinogen concentration and is associated with an increased microvascular thrombosis rate

Publisher Copyright: © 2019 by the authors. Licensee MDPI, Basel, Switzerland.Background and Objective: Thrombosis due to inherited hypercoagulability is an issue that has been raised in microvascular flap surgery previously. We analyzed the association of a single nucleotide polymorphism (SNP) in rs2066865 in the fibrinogen gamma chain (FGG) gene, alteration in plasma fibrinogen concentration, and presence of microvascular flap thrombosis. Materials and Methods: A total of 104 adult patients with microvascular flap surgery were subjected to an analysis of the presence of SNP rs2066865 in the FGG gene. Alterations in plasma fibrinogen concentration according to genotype were determined as a primary outcome, and flap thrombosis was defined as a secondary outcome. Results: Flap thrombosis was detected in 11.5% of patients (n = 12). Successful revision of anastomosis was performed in four patients, resulting in a microvascular flap survival rate of 92.3%. We observed an increase in plasma fibrinogen concentration in genotype G/A and A/A carriers (G/G, 3.9 (IQR 4.76-3.04); G/A, 4.28 (IQR 5.38-3.18); A/A, 6.87 (IQR 8.25-5.49) (A/A vs. G/A, p = 0.003 and A/A vs. G/G, p = 0.001). Within group differences in microvascular flap thrombosis incidence rates were observed—G/G 6/79 (7.59%); G/A 5/22 (22.7%); A/A 1/3 (33.3%) (OR 0.30 95%; CI 0.044 to 0.57), p = 0.016; RR 3.2—when G/G versus G/A and A/A were analyzed respectively. Conclusions: A/A and G/A genotype carriers of a single nucleotide polymorphism in rs2066865 in the fibrinogen gamma chain gene had a higher plasma fibrinogen concentration, and this might be associated with an increased microvascular flap thrombosis incidence rate. Determined polymorphism could be considered as a genetic marker associated with microvascular flap thrombosis development. To confirm the results of this study, the data should be replicated in a greater sample size.Peer reviewe

Prediction of the Difficult Laryngoscopy with Ultrasound Measurements of Hyomental Distance

Ultrasound measurement of hyomental distance is promising as a predictor for difficult laryngo-scopy in cases of difficult airway management. The aim of the study was to evaluate the prognos-tic value of ultrasound measurement of hyomental distance (HMD) for prediction of difficultlaryngoscopy. Hyomental distance was sonographically measured in neutral (HMDn) and extremehead extension (HMDe) positions for fifty-six patients scheduled for elective surgery requiring tra-cheal intubation. Then the hyomental distance ratio (HMDR) was calculated. According to pres-ence of difficult laryngoscopy assessed by the Cormack–Lehane (CL) score, patients weredivided into a difficult laryngoscopy group (DL, n = 15) and easy laryngoscopy group (EL, n = 41).We calculated the sensitivity and specificity of HMDn, HMDe, and HMDR for difficult laryngo-scopy. DL was present in 15 (27%) patients. We found a significant intergroup difference inHMDR between the DL and EL groups (1.12 ± 0.04 vs. 1.24 ± 0.06, respectively;p< 0.001). Incontrast, we were not able to find a significant difference for HMDn and HMDr. HMDR had thehighest sensitivity 86.7% and specificity 85.4% (p< 0.01) to predict difficult laryngoscopy, wherethe area under the curve was 0.939;p< 0.01 for HDMR < 1.2 cm. Moreover, we found that diffi-cult laryngoscopy was associated with higher body mass index (BMI), with higher values in theDL group compared to EL patients (34.3 ± 9.1 vs. 28.5 ± 5.7 kg/m2, respectively;p= 0.035).HMDR < 1.2 cm measured by ultrasound might have a good predictive value for prediction of diffi-cult laryngoscopy.publishersversionPeer reviewe

Thromboelastometry for Assessing Risks of Free Flap Thrombosis in Patients Undergoing Microvascular Surgery

Publisher Copyright: © Copyright © 2020 Vanags, Stepanovs, Ozolina, Mukans, Bjertnaes and Mamaja. Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Introduction: Coagulation assessment is often missing in microvascular surgery. We aimed at evaluating the predictive value of thromboelastometry for free flap thrombosis in microvascular surgery patients. Materials and Methods: We enrolled 103 adult patients with traumatic injuries scheduled for microvascular free flap surgery into a prospective observational study. Thirty-six patients with recent trauma underwent surgery within 30 days (ES group), and were compared with 67 trauma patients who underwent surgery later than 30 days (late surgery, LS group) after the injury. Rotational thromboelastometry (RTE) was performed before surgery. Functional fibrinogen to platelet ratio (FPR) ≥ 42 was selected as the main hypercoagulability index. Free flap thrombosis was set as primary outcome. Thrombotic risk factors and duration of surgery related to free flap thrombosis were secondary outcomes. Statistical significance p 240 min, the risk of free flap thrombosis increased (OR 3.5, CI 1.16-10.6; p = 0.026) with 93.3% sensitivity and 86.7% specificity (AUC 0.85; p = 0.007). In contrast, in LS patients hypercoagulability increased the odds of free flap thrombosis (OR 8.83, CI 1.74–44.76; p = 0.009). Moreover, a positive correlation was found between FPR ≥ 42 and free flap thrombosis rate (r = 0.362; p = 0.003). In the LS group, the presence of thrombogenic comorbidities correlated with free flap thrombosis rate (OR 7, CI 1.591–30.8; p = 0.01). Conclusions: In LS patients with thrombogenic comorbidities, thromboelastometry supports the detection of hypercoagulability and predicts free flap thrombosis risk. In ES patients, postoperative hypercoagulability did not predict free flap thrombosis. Prolonged surgery time should be considered as a risk factor.Peer reviewe

Perineural Administration of Dexmedetomidine in Axillary Brachial Plexus Block Provides Safe and Comfortable Sedation : A Randomized Clinical Trial

Publisher Copyright: Copyright © 2022 Rocans, Ozolina, Andruskevics, Narchi, Ramane and Mamaja.Dexmedetomidine prolongs the duration of regional block while its systemic sedative effect when administered perineurally is unknown. We aimed to evaluate the systemic sedative effect of perineural dexmedetomidine in patients after axillary brachial plexus block (ABPB). This single-blinded prospective randomized control trial included 80 patients undergoing wrist surgery receiving ABPB. Patients were randomized into two groups – Control group (CG, N = 40) and dexmedetomidine group (DG, N = 40). Both groups received ABPB with 20 ml of 0.5% Bupivacaine and 10 ml of 2% Lidocaine. Additionally, patients in DG received 100 mcg of dexmedetomidine perineurally. Depth of sedation was evaluated using Narcontrend Index (NI) and Ramsay Sedation Scale (RSS) immediately after ABPB and in several time points up to 120 min. Duration of block as well as patient satisfaction with sedation was evaluated using a postoperative survey. Our results showed that NI and RSS statistically differed between groups, presenting a deeper level of sedation during the first 90 min in DG compared to controls, P < 0.001. In the first 10 to 60 min after ABPB the median RSS was 4 (IQR within median) and median NI was 60 (IQR 44–80) in DG group, in contrast to CG patients where median RSS was 2 (IQR within median) and median NI was 97 (IQR 96–98) throughout surgery. The level of sedation became equal in both groups 90 and 120 min after ABPB when the median NI value was 98 (97–99) in DG and 97.5 (97–98) in CG, P = 0.276, and the median RSS was 2 (IQR within median) in both groups, P = 0.128. No significant intergroup differences in hemodynamic or respiratory parameters were found. Patients in DG expressed satisfaction with sedation and 86.5% noted that the sensation was similar to ordinary sleep. In DG mean duration of motor block was 13.5 ± 2.1 h and sensory block was 12.7 ± 2.8 h which was significantly longer compared to CG 6.3 ± 1.5 h, P < 0.001 and 6.4 ± 1.8 h, P < 0.001. We found that beside prolongation of analgesia, perineural administration of dexmedetomidine might provide rather safe and comfortable sedation with no significant effect on hemodynamic or respiratory stability and yields a high level of patient satisfaction.publishersversionPeer reviewe

The Impact of Different Ventilatory Strategies on Clinical Outcomes in Patients with COVID-19 Pneumonia

Funding Information: The authors declare that the article publication fee has been covered with the support of Educational Centre of Riga East University Hospital. No funders were involved in the study design, collection, analysis, interpretation of data or writing of this article. Publisher Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland.Introduction: The aim was to investigate the impact of different ventilator strategies (non-invasive ventilation (NIV); invasive MV with tracheal tube (TT) and with tracheostomy (TS) on outcomes (mortality and intensive care unit (ICU) length of stay) in patients with COVID-19. We also assessed the impact of timing of percutaneous tracheostomy and other risk factors on mortality. Methods: The retrospective cohort included 868 patients with severe COVID-19. Demographics, MV parameters and duration, and ICU mortality were collected. Results: MV was provided in 530 (61.1%) patients, divided into three groups: NIV (n = 139), TT (n = 313), and TS (n = 78). Prevalence of tracheostomy was 14.7%, and ICU mortality was 90.4%, 60.2%, and 30.2% in TT, TS, and NIV groups, respectively (p < 0.001). Tracheostomy increased the chances of survival and being discharged from ICU (OR 6.3, p < 0.001) despite prolonging ICU stay compared to the TT group (22.2 days vs. 10.7 days, p < 0.001) without differences in survival rates between early and late tracheostomy. Patients who only received invasive MV had higher odds of survival compared to those receiving NIV in ICU prior to invasive MV (OR 2.7, p = 0.001). The odds of death increased with age (OR 1.032, p < 0.001), obesity (1.58, p = 0.041), chronic renal disease (1.57, p = 0.019), sepsis (2.8, p < 0.001), acute kidney injury (1.7, p = 0.049), multiple organ dysfunction (3.2, p < 0.001), and ARDS (3.3, p < 0.001). Conclusions: Percutaneous tracheostomy compared to MV via TT significantly increased survival and the rate of discharge from ICU, without differences between early or late tracheostomy.publishersversionPeer reviewe