Background and Objectives: Postoperative cognitive disturbances (POCD) can significantly alter postoperative recovery. Inadequate intraoperative cerebral oxygen supply is one of the inciting causes of POCD. Near-infrared spectroscopy (NIRS) devices monitor cerebral oxygen saturation continuously and can help to guide intraoperative patient management. The aim of the study was to evaluate the applicability of the NIRS-based clinical algorithm during spinal neurosurgery and to find out whether it can influence postoperative cognitive performance. Materials and Methods: Thirty four patients scheduled for spinal neurosurgery were randomized into a study group (n = 23) and a control group (n = 11). We monitored regional cerebral oxygen saturation (rScO2) throughout surgery, using a NIRS device (INVOS 4100). If rScO2 dropped bilaterally or unilaterally by more than 20% from baseline values, or under an absolute value of 50%, the NIRS-based algorithm was initiated in the study group. In the control group, rScO2 was monitored blindly. To evaluate cognitive function, Montreal-Cognitive Assessment (MoCA) scale was used in both groups before and after the surgery. Results: In the study group, rScO2 dropped below the threshold in three patients and the NIRS-based algorithm was activated. Firstly, we verified correct positioning of the head; secondly, we increased mean systemic arterial pressure in the three patients by injecting repeated intravenous bolus doses of Ephedrine, ultimately resulting in an rScO2 increase above the approved threshold level. None of the three patients showed POCD. In the control group, one patient showed a drop in rScO2 of 34% from baseline and presented with a POCD. RScO2 drop occurred with other stable intraoperative measurements. Conclusions: A significant rScO2 drop may occur during spinal surgery in prone position despite other intraoperative measurements remaining stable, allowing it to stay otherwise unrecognized. Use of the NIRS-based clinical algorithm can help to avoid POCD in patients after spinal surgery.

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.

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.

Microvascular flap surgery is a widely acknowledged procedure for significant defect reconstruction. Multiple flap complication risk factors have been identified, yet there are limited data on laboratory biomarkers for the prediction of flap loss. The controlling nutritional status (CONUT) score has demonstrated good postoperative outcome assessment ability in diverse surgical populations. We aim to assess the predictive value of the CONUT score for complications in microvascular flap surgery. This prospective cohort study includes 72 adult patients undergoing elective microvascular flap surgery. Preoperative blood draws for analysis of full blood count, total plasma cholesterol, and albumin concentrations were collected on the day of surgery before crystalloid infusion. Postoperative data on flap complications and duration of hospitalization were obtained. The overall complication rate was 15.2%. True flap loss with vascular compromise occurred in 5.6%. No differences in flap complications were found between different areas of reconstruction, anatomical flap types, or indications for surgery. Obesity was more common in patients with flap complications (p = 0.01). The CONUT score had an AUC of 0.813 (0.659–0.967, p = 0.012) for predicting complications other than true flap loss due to vascular compromise. A CONUT score > 2 was indicated as optimal during cut-off analysis (p = 0.022). Patients with flap complications had a longer duration of hospitalization (13.55, 10.99–16.11 vs. 25.38, 14.82–35.93; p = 0.004). Our findings indicate that the CONUT score has considerable predictive value in microvascular flap surgery.

Complex microvascular techniques and in-depth knowledge of blood rheology and microanastomosis function are required for success in microvascular flap surgery. Substantial progress has been achieved in preventing complications, but the rate of flap loss is still significant and can have significant adverse effects on the patient. Flap thrombosis, flap hematoma, and flap loss are the most frequent and severe major surgical complications. Advances in understanding the pathophysiology of different flap complications, the use of preoperative risk assessment and new treatment concepts could improve the perioperative care of microvascular flap surgery patients. Our aim was to outline novel avenues for best practice and provide an outlook for further research of anesthesia and perioperative care concepts in microvascular flap surgery.

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.