Blood Volume Research Articles

Blood-pool SUV analysis of 99mTc-galactosyl human serum albumin (99mTc-GSA) normalized by blood volume for prediction of short-term survival in severe liver failure: preliminary report.

This study evaluated the usefulness of SUV analysis of 99mTc-galactosyl human serum albumin (99mTc-GSA) scintigraphy including SUV analysis of the cardiac blood pool normalized by blood volume as a predictor of short-term survival in severe liver failure. We enrolled 24 patients with severe liver failure who underwent 99mTc-GSA scintigraphy and were admitted to the intensive care unit. Patients were divided into survival and non-survival groups at 7, 14, and 28days from the performance of 99mTc-GSA scintigraphy. From SPECT images we calculated SUVs of the cardiac blood pool, performing normalization for body weight, lean body weight, Japanese lean body weight, and blood volume and we calculated SUVs of the liver, normalizing by body weight, lean body weight, and Japanese lean body weight. We also calculated the uptake ratio of the heart at 15min to that at 3min (HH15) and the uptake ratio of the liver at 15min to the liver plus the heart at 15min (LHL15) from planar images of 99mTc-GSA scintigraphy. There were significant differences between the 7day survival and non-survival groups for all SUVs of the heart and the liver and HH15, for 14day survival groups in SUVs of the heart normalized by Japanese lean body weight and blood volume, and no significant differences between 28day survival groups for any SUVs, HH15, or LHL15. Although the difference was not significant, SUV analysis of the heart normalized by blood volume showed the highest value for the area under the receiver-operating-characteristics curve for both 7day and 14day survival. SUV analysis of 99mTc-GSA including SUV analysis of cardiac blood pool normalized by blood volume is of value for prediction of short-term survival in cases with severe liver failure.

Pulmonary emphysema: the assessment of lung perfusion with Dual-Energy CT and pulmonary scintigraphy.

To assess the correlation of quantitative data of pulmonary Perfused Blood Volume (PBV) on Dual-Energy CT (DECT) datasets in patients with moderate - severe Pulmonary Emphysema (PE) with Lung Perfusion Scintigraphy (LPS) as the reference standard. The secondary endpoints are the correlation between the CT densitometric analysis and the visual assessment of parenchymal destruction with PBV. Patients with moderate - severe PE candidate to Lung Volumetric Reduction (LVR), with available a pre-procedural LS and a contrast-enhanced DECT were retrospectively included. DECT studies were performed with a 3rd generation Dual-Source CT and the PBV was obtained with a 3-material decomposition algorithm. The CT densitometric analysis was performed with a dedicated commercial software (Pulmo3D). The Goddard Score was used for visual assessment. The perfusion LS were performed after the administration of albumin macroaggregates labeled with 99mTechnetium. The image revision was performed by two radiologists or nuclear medicine physicians blinded, respectively, to LS and DECT data. The statistical analysis was performed with nonparametric tests. Thirty-one patients (18 males, median age 69 y.o., interquartile range 62-71 y.o.) with moderate - severe PE (Median Goddard Score 14/20 and 31% of emphysematous parenchyma at quantitative CT) candidate to LVR were retrospectively included. The median enhancement on PBV was 17 HU. Significant correlation coefficients were demonstrated between lung PBV and LS, poor in apical regions (Rho = 0.1-0.2) and fair (Rho = 0.3-0.5) in middle and lower regions. No significant correlations were recorded between the CT densitometric analysis, the visual score, and the PBV. Lung perfusion with PBV on DECT is feasible in patients with moderate - severe PE candidate to LVR, and has a poor to fair agreement with LPS.

The practical use of artificial intelligence in Transfusion Medicine and Apheresis

BackgroundBlood and plasma volume calculations are a daily part of practice for many Transfusion Medicine and Apheresis practitioners. Though many formulas exist, each facility may have their own modifications to consider. ChatGPT (Generative Pre-trained Transformer) provides a new and exciting pathway for those with no programming experience to create personalized programs to meet the demands of daily practice. Additionally, this pathway creates computer programs that provide accurate and reproducible outputs. Herein, we aimed to create a step-by-step process for clinicians to create customized computer programs for use in everyday practice. MethodsWe created a process of inputs to ChatGPT-40, which generated computer programming code. This code was copied and pasted into Notepad (and saved as a Python file) and Google Colaboratory to verify functionality. We validated the durability of our process by repeating it over a 5-day timeframe and by recruiting volunteers to reproduce our outputs using the suggested process. ResultsComputer code generated by ChatGPT-40 in response to our common language inputs was accurate and durable over time. The code was fully functional in both Python and Colaboratory. Volunteers reproduced our process and outputs with minimal assistance. ConclusionWe analyzed the practical application of ChatGPT-40 and artificial intelligence (AI) to perform daily calculations encountered in Transfusion Medicine. Our results provide a proof of concept that people with no programming experience can create customizable solutions for their own facilities. Our future work will expand to the creation of comprehensive and customizable websites designed for each individual user.

Experimental study of contrast-enhanced ultrasound in the evaluation of random-pattern flap blood supply in the early postoperative stage in rats.

This study aims to investigate whether contrast-enhanced ultrasound (CEUS) could be used to reveal the status of blood supply of the superficial flap of rat model in the early postoperative stage. One viable and one ischemic random-pattern flap were prepared on the left and right back of the same rat respectively with a number of 40. CEUS examinations were applied within 12 h and 7 days postoperatively, and the quantitative measurements of microvascular blood volume (BV) of the base and the end of both flaps were expressed using acoustic intensity as a ratio to that of the healthy skin. Within 12 h post operation, there was a smaller BV value of the ischemic ends than that of both the ischemic bases and viable ends (p < 0.001), while no difference was indicated between ischemic bases and viable bases or between viable bases and viable ends. The same result was provided 7 days post operation. Microcirculation of superficial tissues such as random-pattern flaps in this rat model can be assessed quantitatively by CEUS. It could sensitively and accurately reveal the objective status of tissue perfusion in the early postoperative stage.

A translational study evaluating a ruggedized portable oxygen concentrator versus an oxygen cylinder in simulated polytrauma intubation of swine.

Portable oxygen concentrators (POCs) are medical devices that use filters to selectively remove nitrogen from ambient air to produce concentrated, medical-grade oxygen. This is the first study to evaluate a ruggedized POC's performance during simulated polytrauma intubation. Twenty-seven swine were intubated and anesthetized with ketamine. At T=0, animals were extubated, received a chest wall injury, a tibia fracture, and 20% total blood volume controlled hemorrhage was initiated. At T=10 min, the swine were pre-oxygenated using a bag-valve mask connected to one of three randomized oxygen sources: (1) a ruggedized POC, (2) a M-15 oxygen cylinder, or (3) room air (control). At T=12 min, animals were re-intubated to simulate polytrauma intubation and connected to the test oxygen source for the remainder of the experiment. Surviving animals entered a 2-h period where partial pressure of oxygen (PaO2), oxygen saturation (SpO2), and regional oxygen saturation (rSO2) were monitored. Groups were compared using analysis of variance (ANOVA), Fisher's exact, log-rank analysis, or mixed-effects model as appropriate. All animals survived except one in the POC group. Mixed-effects models revealed differences between groups with regards to PaO2 (p<0.0001) and SpO2 (p=0.006). Based on post hoc analysis, oxygen cylinder PaO2 was superior to both POC and control, but there were no differences between POC and control PaO2. There were statistically and clinically significant differences in SpO2 during periods of pre-oxygenation (T=10‒12 min), intubation (T=12‒14 min), and immediately after intubation (T=14‒20 min). The POC battery was consumed in 43±13 min. In our swine model, a single, ruggedized POC provided inferior amounts of oxygen supplementation compared to an oxygen cylinder and performed no better than room air.

Peculiarities of cerebral blood flow and vascular reactivity in patients with large and giant tumors of the cerebello-pontine angle

Background. Vestibular schwannomas and posterior fossa meningiomas are one of the most difficult tumors for surgical treatment. The mortality rate after their removal reaches 13,5 %. The main causes of death are hemorrhagic and ischemic complications. There are no studies in the literature on tissue perfusion of brainstem structures and cerebellum and reactivity of vertebral and basilar arteries in patients with extraaxial tumors of the posterior cranial fossa. Therefore, the study of the blood supply of the brainstem structures and cerebellum, as well as the functional characteristics of the vertebral and basilar arteries in these patients is of considerable interest.Aim. To evaluate tissue perfusion of the pons and cerebellum, as well asthe reactivity of the vertebral and basilar arteries in patients with large and giant vestibular schwannomas and posterior fossa meningiomas.Materials and methods. Eighty-two patients with large and giant extraaxial tumors of the base of the posterior cranial fossa were examined. The median age was 54 [44; 61] years. Vestibular schwannomas were diagnosed in 52.4 % of patients, and meningiomas of the posterior cranial fossa were diagnosed in 47.6 %. All patients underwent duplex scanning of the basilar and vertebral arteries. We evaluated linear blood flow and coefficients of reactivity and index of vasomotor reactivity. We investigated the metabolic reactivity of cerebral blood flow by conducting hyper- and hypocapnic tests. Computed tomography perfusion imaging was performed in 18 patients. We detected cerebral blood volume, cerebral blood flow, mean transit time of contrast agent and time to peak of contrast agent. Measurements were carried out in six regions of interest located symmetrically on the pons and in the white matter of the cerebellar hemispheres on the side of the tumor and on the opposite side.Results. Linear blood flow rates in the intracranial segments of the vertebral and the basilar arteries in patients with tumors were higher than in the comparison group (p&lt;0.05). These patients are characterized by a decrease of reactivity coefficients in the vertebral and basilar arteries, especially when performing hypercapnic tests (p &lt;0.05). Paradoxical reactivity and areactivity were diagnosed in 34.9 % of patients with vestibularschwannomas and 25.6 % with meningiomas. In the pons on the side of the tumor in patients with vestibularschwannomas, a decrease in cerebral blood flow by 19.3 %, an increase in cerebral blood volume by 33.3 % and an increase in mean transit time of contrast agent and in time to peak of contrast agent by 48.1 % and 71.1 % (p &lt;0.05) were found. In patients with meningiomas in the pons on the side of the tumor, all perfusion parameters were higher (p&lt;0.05). In the deep regions of the cerebellar hemisphere on the side of the tumor in patients with tumors, all perfusion parameters were higher compared to the opposite side.Conclusion. The results of the study made it possible to quantify cerebral blood flow in patients with large and giant vestibular schwannomas and meningiomas of the posterior cranial fossa base. The revealed changes indicate the risk of developing pathological vascular reactions and disorders of cerebral blood flow in the postoperative period.

Assessing Cerebral Microvascular Volumetric Pulsatility with High-Resolution 4D CBV MRI at 7T.

Arterial pulsation is crucial for promoting fluid circulation and for influencing neuronal activity. Previous studies assessed the pulsatility index based on blood flow velocity pulsatility in relatively large cerebral arteries of human. Here, we introduce a novel method to quantify the volumetric pulsatility of cerebral microvasculature across cortical layers and in white matter (WM), using high-resolution 4D vascular space occupancy (VASO) MRI with simultaneous recording of pulse signals at 7T. Microvascular volumetric pulsatility index (mvPI) and cerebral blood volume (CBV) changes across cardiac cycles are assessed through retrospective sorting of VASO signals into cardiac phases and estimating mean CBV in resting state (CBV0) by arterial spin labeling (ASL) MRI at 7T. Using data from 11 young (28.4±5.8 years) and 7 older (61.3±6.2 years) healthy participants, we investigated the aging effect on mvPI and compared microvascular pulsatility with large arterial pulsatility assessed by 4D-flow MRI. We observed the highest mvPI in the cerebrospinal fluid (CSF) on the cortical surface (0.19±0.06), which decreased towards the cortical layers as well as in larger arteries. In the deep WM, a significantly increased mvPI (p = 0.029) was observed in the older participants compared to younger ones. Additionally, mvPI in deep WM is significantly associated with the velocity pulsatility index (vePI) of large arteries (r = 0.5997, p = 0.0181). We further performed test-retest scans, non-parametric reliability test and simulations to demonstrate the reproducibility and accuracy of our method. To the best of our knowledge, our method offers the first in vivo measurement of microvascular volumetric pulsatility in human brain which has implications for cerebral microvascular health and its relationship research with glymphatic system, aging and neurodegenerative diseases.

Use of Modified Gompertz Kinetic Modelling to Predict Biogas Production from Co-Digestion of Two Substrates and Other Treatments

This research was conducted with the aim of using Gompertz kinetic model to predict biogas production. The substrates used are the co-digestion of pig and poultry dungs. Batch culture of anaerobic digestion was used while MgSO4, Bovine blood, Charcoal water and water of pH 8 were used as various treatments. Three batches of digestions were done. From the results and statistical kinetic modelling, magnesium sulphate which serve as source of water hardness proved to enhance biogas production. This is because it serves as both salt and catalyst. Bovine blood also showed the same effect. For the charcoal water, it enhanced methane production by the increase of carbon level in C:N ratio. The research recommends as follows. That the quantity of the substrates should be enough to ensure more gas yield. The volume of blood should not be more than the water used in the slurry formation as this could affect proper mixing. The carbon content of the lignocellulose should be increased using charcoal water in slurry preparation to ensure formation of Methane (CH4) which is the main biogas. And finally that measured amount of bovine blood, Magnesium Sulphate and Charcoal can be used as additive in biogas production.

Internal blood loss in fatal liver lacerations - determining lethality from relative blood loss.

Certificates of medical evidence are often used to aid the court in assessing the cause and severity of a victim's injuries. In cases with significant blood loss, the question whether the bleeding itself was life-threatening sometimes arises. To answer this, the volume classification of hypovolemic shock described in ATLS® is commonly used as an aid, where a relative blood loss > 30% is considered life-threatening. In a recent study of deaths due to internal haemorrhage, many cases had a relative blood loss < 30%. However, many included cases had injuries which could presumably cause deaths via other mechanisms, making the interpretation uncertain. To resolve remaining ambiguity, we studied whether deaths due to isolated liver lacerations had a relative blood loss < 30%, a cause of death where the mechanism of death is presumably exsanguination only. Using the National Board of Forensic Medicine autopsy database, we identified all adult decedents, who had undergone a medico-legal autopsy 2001-2021 (n = 105 952), where liver laceration was registered as the underlying cause of death (n = 102). Cases where death resulted from a combination of also other injuries (n = 79), and cases that had received hospital care, were excluded (n = 4), leaving 19 cases. The proportion of internal haemorrhage to calculated total blood volume in these fatal pure exsanguinations ranged from 12 to 52%, with 63% of cases having a proportion < 30%. Our results lend further support to the claim that the volume classification of hypovolemic shock described in ATLS® is inappropriate for assessing the degree of life-threatening haemorrhage in medico-legal cases.

The non-haemorrhagic vagal response to trauma: a review of hypotensive and bradycardic responses to injury in the absence of bleeding.

Trauma has the potential to cause haemorrhage, tissue damage, pain, visceral manipulation and psychological distress. Each of these consequences of trauma can cause changes in autonomic outflow, which dictates a patient's vital signs. Patients who are hypotensive and bradycardic due to a vagally mediated parasympathetic response to pain, psychological distress and visceral manipulation may be confused with those who exhibit bradycardia and hypotension following significant blood volume loss. This review summarises literature that describes specific stimuli, patterns of injury and patient characteristics that are associated with a non-haemorrhagic vagal response to trauma. Twenty-six records described predominantly parasympathetic responses to trauma (both blunt and penetrating) and surgery ("iatrogenic trauma"). Such a non-haemorrhagic vagal response occurs following a wide variety of injury patterns. Patient age and sex are poor predictors of the likelihood of a non-haemorrhagic vagal response. The development and resolution of a non-haemorrhagic vagal response occurs over a heterogenous time period. It is unclear whether speed of onset and resolution is linked to the pattern of injury or other factors causing a predominantly parasympathetic response following non-haemorrhagic trauma. The pattern of injury, patient demographic and speed of onset / resolution associated with the non-haemorrhagic vagal response to trauma may is heterogenous. It is therefore challenging to clinically distinguish between the hypotensive bradycardia due to hypovolaemia secondary to haemorrhage, or a parasympathetic response to trauma in the absence of bleeding.

Perfusion-weighted MRI patterns in neuropsychiatric systemic lupus erythematosus: a systematic review and meta-analysis.

Neuropsychiatric Systemic Lupus Erythematosus (NPSLE) is a complex manifestation of Systemic Lupus Erythematosus (SLE) characterized by a wide range of neurological and psychiatric symptoms. This study aims to elucidate the patterns of Perfusion-Weighted MRI (PWI) in NPSLE patients compared to SLE patients without neuropsychiatric manifestations (non-NPSLE) and healthy controls (HCs). A systematic search was conducted in PubMed/Medline, Embase, Web of Science, and Scopus for studies utilizing PWI in NPSLE patients published through April 14, 2024. Cerebral blood flow (CBF) data from NPSLE, non-NPSLE patients, and HCs were extracted for meta-analysis, using standardized mean difference (SMD) as an estimate measure. For studies lacking sufficient data for inclusion, CBF, cerebral blood volume (CBV), and mean transit time (MTT) were reviewed qualitatively. Our review included eight observational studies employing PWI techniques, including dynamic susceptibility contrast (DSC) and arterial spin labeling (ASL). The meta-analysis of NPSLE compared to non-NPSLE incorporated four studies, encompassing 104 NPSLE patients and 90 non-NPSLE patients. The results revealed an SMD of -1.42 (95% CI: -2.85-0.00, I2: 94%) for CBF in NPSLE compared to non-NPSLE. PWI reveals informative patterns of cerebral perfusion, showing a significant reduction in mean CBF in NPSLE patients compared to non-NPSLE patients. Our qualitative synthesis highlights these changes, particularly in the frontal and temporal lobes. However, the existing data exhibits considerable heterogeneity and limitations.

Comparison of Perfusion Imaging Definitions of the No-Reflow Phenomenon after Thrombectomy-What Is the Best Perfusion Imaging Definition?

We performed an external validation of 4 existing published definitions of no-reflow in thrombectomy patients with extended Thrombolysis in Cerebral Infarction scale 2c to 3 (eTICI2c-3) angiographic reperfusion who underwent 24-hour perfusion imaging from 2 international randomized controlled trials (EXTEND-IA TNK part-1 and 2) and a multicenter prospective observational study. Receiver-operating-characteristic and Bayesian-information-criterion (BIC) analyses were performed with the outcome variable being dependent-or-dead at 90-days (modified Rankin Score [mRS] ≥3). Of 131 patients analyzed, the prevalence of no-reflow significantly varied between definitions (0.8-22.1%; p < 0.001). There was poor agreement between definitions (kappa 5/6 comparisons <0.212). Among patients with no-reflow according to at least 1 definition, there were significant differences between definitions in the intralesional interside differences in cerebral blood flow (CBF) (p = 0.006), cerebral blood volume (CBV) (p < 0.001), and mean-transit-time (MTT) (p = 0.005). No-reflow defined by 3 definitions was associated with mRS ≥3 at 90 days. The definition of >15% CBV or CBF asymmetry was the only definition that improved model fit on BIC analysis (ΔBIC = -8.105) and demonstrated an association between no-reflow and clinical outcome among patients with eTICI3 reperfusion. Existing imaging definitions of no-reflow varied significantly in prevalence and post-treatment perfusion imaging profile, potentially explaining the variable prevalence of no-reflow reported in literature. The definition of >15% CBV or CBF asymmetry best discriminated for functional outcome at 90 days, including patients with eTICI3 reperfusion. ANN NEUROL 2024.

A Pilot and Feasibility Study of Continuous Cardiac Output and Blood Pressure Monitoring during Intermittent Hemodialysis.

Hypotension is common during intermittent hemodialysis (IHD) and may be due to a decreased cardiac index (CI). However, no study has simultaneously and continuously measured CI and mean arterial pressure (MAP) to understand the prevalence, severity, and duration of CI decreases or relate them to MAP, blood volume (BV) and net ultrafiltration (NUF) rate. In a prospective, pilot and feasibility investigation, we studied 10 chronic IHD patients. We used the ClearSight System™ to continuously monitor CI and MAP; the CRIT-LINE®IV monitor to detect BV changes and collected data on NUF rate. Device tolerance and compliance was 100%. All patients experienced at least ≥ 1 episode of severe CI decrease (&gt; 25% from baseline), with a median duration of 24 minutes [IQR 6-87] and of 68 minutes [14-106] for moderate decreases (&gt;15% but  25% from baseline). Eight patients experienced a low CI state (&lt;2.2 L/min/m2). The lowest CI was 0.9 L/min/m2 with a concomitant MAP of 94 mmHg. When the fall in CI was severe, MAP increased in 58% of cases and remained stable in 28%. Overall, CI decreased by -0.55 L/min/m2 when BV decrease was moderate vs mild (p&lt;0.001) and by -0.8 L/min/m2 when NUF rate was high vs low (p&lt;0.001). Continuous CI monitoring is feasible in IHD and shows frequent moderate-severe CI decreases, sometimes to low CI state levels. Such decreases are typically associated with markers of decreased intravascular volume status but not with a decrease in MAP, implying marked vasoconstriction.

Is it useful to wash stored red blood cells in cardiopulmonary bypass priming fluid for neonatal cardiac surgery? A single-centre retrospective study.

Neonatal cardiac surgery requires careful consideration of cardiopulmonary bypass (CPB) priming fluid composition due to small blood volume and immature physiology. This study investigated the impact of allogeneic stored red blood cells (RBCs) processed using an autotransfusion system in CPB priming fluid for neonates. We compared perioperative parameters, inflammatory mediators, coagulation indicators, vasoactive-inotropic score (VIS) and clinical outcomes between neonates receiving unwashed (n = 56) and washed (n = 45) RBCs in CPB priming fluid. Regression models were used to assess the independent association between RBC washing and patient outcomes. The autotransfusion system improved stored RBC quality. The washed group showed higher peak haematocrit (p < 0.01) and haemoglobin levels (p = 0.04) during CPB, an increased oxygen delivery index during rewarming (p < 0.05) and lower postoperative lactate levels and VIS (p < 0.05). Inflammatory (IL-6, IL-8 and IL-10) and coagulation parameters (D-dimer, fibrinogen and fibrin degradation product) fluctuated compared with baseline but did not significantly differ between groups. The washed group had a lower incidence of hyperlactacidaemia and delayed sternal closure at CPB weaning. Adding washed allogeneic stored RBCs to neonatal CPB priming fluid reduced postoperative lactate elevation and VIS without early improvement in the inflammatory and coagulation systems.

Perfusion imaging predicts short-term clinical outcome in isolated posterior cerebral artery occlusion stroke.

Ischemic strokes due to isolated posterior cerebral artery (PCA) occlusions represent 5% of all strokes but have significant impacts on patients' quality of life, primarily due to visual deficits and thalamic involvement. Current guidelines for acute PCA occlusion management are sparse, and the prognostic value of perfusion imaging parameters remains underexplored. We conducted a retrospective analysis of 32 patients with isolated PCA occlusions treated at Johns Hopkins Medical Institutions between January 2017 and March 2023. Patients underwent pretreatment perfusion imaging, with perfusion parameters analyzed using RAPID software. The primary outcome was short-term clinical outcome as measured by the National Institutes of Health Stroke Scale (NIHSS) at discharge. The median age of the cohort was 70years, with 34% female and 66% male. Significant correlations were found between NIHSS at discharge and various perfusion parameters, including time-to-maximum (Tmax) >6seconds (ρ=.55, p=.004), Tmax >8seconds (ρ=.59, p=.002), Tmax >10seconds (ρ=.6, p=.001), mismatch volume (ρ=.51, p=.008), and cerebral blood volume (CBV) < 34% (ρ=.59, p=.002). Tmax and CBV volumes significantly correlated with discharge NIHSS with marginal superiority of Tmax >10seconds and CBV <42% volumes. These findings suggest that CT and MR perfusion imaging can play a crucial role in the acute management of PCA strokes, though larger, standardized studies are needed to validate these results and refine imaging thresholds specific to posterior circulation infarcts.

Blood on the drapes: A multispecialty comparison of blood spill estimates.

Estimated blood loss (EBL) is an important part of the perioperative process. This project aims to determine the accuracy of perioperative team members to estimate blood volume on drapes and the operating room floor. Aliquots of unused human blood were used to create surgical scenarios, and standardized pictures and videos were taken. Physicians, residents, nurses, medical students, and surgical technicians were surveyed and asked to estimate the blood volume for each series. Accuracy and consistency of responses was analyzed. One hundred and forty five responses were recorded: 57 attending physicians, 36 residents, 27 registered nurses, 17 medical students, and seven circulating surgical techs. Median percent error (PE) for all cases was 211.11%, demonstrating a global overestimation of blood volume. PE for the 150mL images was statistically significantly lower than that of the 50 and 100mL images. Circulating Surgical Technicians were the most accurate group, with a median PE of 125%, followed closely by Medical Students (PE=158.33%). The most accurate specialty was Orthopedics (PE=168.06%). The least accurate groups were Attending Physicians (PE=286.11%) and General surgery (GSGY) (PE=327.78%). The most accurate orthopedic surgery and GSGY subspecialties were Hand (PE=237.64%) and Vascular (PE=108.33%), respectively. Statistical analyses showed no significant differences by clinical role, surgical specialty, or subspecialty. This study demonstrates a global overestimation of blood volume when using the visual method, with improved accuracy at higher volumes. Our findings highlight the limitations of visual estimation methods for EBL.

Tight Application of a Surgical Tourniquet Prior to Inflation Increases Venous Pressure In the Upper Limb; Potentially Resulting in Increased Blood Loss and Poorer Visibility

Tourniquets are commonly used in extremity surgery to help provide a bloodless operative field to improve visibility and reduce length of procedures. With the development of WALANT (wide awake, local anaesthetic, no tourniquet) techniques, many surgeons undertake surgery without tourniquet inflation. The correct technique of pneumatic tourniquet application is poorly understood by healthcare staff. The application of a tight tourniquet when applied for optional use or use for only a portion of a procedure, rather than for inflation throughout can cause venous engorgement of an extremity leading to increased blood loss and reduced operative field visualisation thereby discouraging surgeons from persevering with WALANT strategies. To determine the effect of tourniquet application tension on limb volume prior to skin incision. 30 volunteers had the volume of their non-dominant forearm measured post-inflation of a surgical tourniquet using two different application techniques. Tight application was defined as the tourniquet fastened using a dynamometer to a tension of 100N. Loose application was defined as the tourniquet fastened using a dynamometer to a tension of 50N. The tourniquet was then inflated to 200mmHg after both application techniques. Exsanguination was performed by elevation of the arm for 1min prior to tourniquet inflation. At 5min the forearm volume was measured using a volume displacement technique. 93% of participants (28/30) had a higher volume of water displaced when the tourniquet was applied tightly. The mean difference between the loose and tight applications was 30.06mls. The increase in volume in tightly applied tourniquets is believed to result from increased intravascular volume. This increase in blood volume can lead to increased intra-operative blood loss and poor intra-operative visualisation when operating without tourniquet inflation. Loose application of the tourniquet pre-inflation appears to prevent sequestration of venous blood in the limb, therefore decreasing operative blood loss and improving view for operating. Level 1; Symptom Prevalence Study.

AEROBIC BLOOD CULTURES AND COMPARISON TO CLINICAL FINDINGS OF FREE-RANGING GREEN TURTLES (CHELONIA MYDAS) IN EAST CENTRAL FLORIDA.

Positive blood cultures have been identified in debilitated, stranded, and deceased green turtles (Chelonia mydas), suggestive of septicemia. Interpretation of these results is often difficult because multiple studies have previously identified bacteremia in clinically healthy reptiles. In this study, paired blood cultures and skin cultures obtained after aseptic preparation of the venipuncture site were collected from 50 immature free-ranging green turtles from Port Canaveral, Florida. Blood culture results were compared with health status (apparently healthy versus unhealthy, based on physical examination findings and appropriate body condition), date of collection, presence of external fibropapillomatosis, healed or unhealed injuries, and presence of barnacles. Weight, body condition score, body condition index, morphometric measures, volume of blood collected, and body temperature were compared between blood culture-positive and blood culture-negative turtles. Positive blood cultures were identified in 14% (7 of 50) of all turtles, including 15.6% (5 of 32) of apparently healthy turtles. Vibrio spp., Bacillus megaterium, Cellulomonas sp., and Staphylococcus pasteuri were isolated in blood culture from apparently healthy individuals. There was a significant association (P = 0.048) between positive skin cultures and positive blood cultures, but isolates obtained were consistently different between paired results. There was no significant association (P > 0.05) between blood culture results and health status, evidence of healed or unhealed injuries, external fibropapillomatosis, or presence of barnacles. Based on the results of this study, positive blood cultures suggestive of nonclinical bacteremia may be present in apparently healthy green turtles. The results of this study will aid the attending clinician in interpretation of blood culture results of apparently healthy or presumed septicemic captive and rehabilitating green turtles as part of the conservation and population recovery of this threatened species.

Pharmacokinetic profiles of methylcobalamin in rats after multiple administration routes by a simple LC-MS/MS assay with a small volume of plasma

Methylcobalamin (MBL) is a vitamin B12 coenzyme and is effective for treating peripheral neuropathies. Little is known about pharmacokinetics (PK) of MBL in animals, we have developed a simple assay for MBL by using only 0.01 mL of plasma for PK of MBL in rats. Under minimal light exposure (<5 lx), MBL was extracted by a simple protein precipitation using methanol and detected by liquid chromatography with tandem mass spectrometry. MBL in rat plasma at 20–10,000 ng/mL was quantified using only 0.01 mL of plasma. Relative error and relative standard deviation met the acceptance criteria in reproducibility assessments, indicating the robustness of the assay. PK of MBL was evaluated after intravenous, intramuscular, and subcutaneous administration. PK of MBL was dose proportional at 5–20 mg/kg in both intramuscular and subcutaneous administrations. Bioavailability after the two dosing routes was complete (ca. 100 %). The incurred sample reanalysis also supported that the assay is robust. The established assay was successfully applied to PK studies in rats to find that MBL showed high bioavailability after intramuscular and subcutaneous administrations.

Evaluation of immunological status in pregnant and aborted women with cytomegal infection in Thi-Qar Governorate

The current study was conducted on aborted and pregnant women suspected of being infected with cytomegalovirus in The-Qar Governorate. (90) Serum samples of pregnant and aborted women were examined using the Enzyme-linked Immunosorbent assay(ELISA). through the examination, (50) sample of women infected with CMV virus were found, with rate of 55.55%, where it was found that (43) sample of them carried the IgG antibody, with a rate of 48.88%, and(5) sample with the IgM immunoglobulin antibody, with a rate of (5.5%), and (2) sample of Igm+IgG, with a rate of (2.2%). Through the study of blood parameters that was conducted on (40) blood samples of women infected with the virus, compared to (10) blood samples of uninfected women there was a decrease in the blood hemoglobin rate (Hb)(11.54%) and compressed blood volume by (0.35) compared to the control group, three were no significant difference(p&gt;0.05) for the total number of white blood cells. When conducting a differential of white blood cells for infected women it was found that there was an increase in the percentage of lymphocytes by (40.50), While no significant differences were observed (p&gt;0.05) in the percentage of monocytes,neutrophils eosinophils, and basophils. As for the phagocytosis factor, an increase in the phagocytosis factor was recorded for infected women compared to the control group, as the phagocytosis factor for infected women reached 12-60% and for the control group 47.10%.