Early thrombocytopenia is associated with an increased risk of mortality in patients with traumatic brain injury treated in the intensive care unit: a Finnish Intensive Care Consortium study.

BACKGROUND: Coagulopathy after traumatic brain injury (TBI) is associated with poor prognosis. PURPOSE: To assess the prevalence and association with outcomes of early thrombocytopenia in patients with TBI treated in the intensive care unit (ICU). METHODS: This is a retrospective multicenter study of adult TBI patients admitted to ICUs during 2003-2019. Thrombocytopenia was defined as a platelet count < 100 × 109/L during the first day. The association between thrombocytopenia and hospital and 12-month mortality was tested using multivariable logistic regression, adjusting for markers of injury severity. RESULTS: Of 4419 patients, 530 (12%) had early thrombocytopenia. In patients with thrombocytopenia, hospital and 12-month mortality were 26% and 48%, respectively; in patients with a platelet count > 100 × 109/L, they were 9% and 22%, respectively. After adjusting for injury severity, a higher platelet count was associated with decreased odds of hospital mortality (OR 0.998 per unit, 95% CI 0.996-0.999) and 12-month mortality (OR 0.998 per unit, 95% CI 0.997-0.999) in patients with moderate-to-severe TBI. Compared to patients with a normal platelet count, patients with thrombocytopenia not receiving platelet transfusion had an increased risk of 12-month mortality (OR 2.2, 95% CI 1.6-3.0), whereas patients with thrombocytopenia receiving platelet transfusion did not (OR 1.0, 95% CI 0.6-1.7). CONCLUSION: Early thrombocytopenia occurs in approximately one-tenth of patients with TBI treated in the ICU, and it is an independent risk factor for mortality in patients with moderate-to-severe TBI. Further research is necessary to determine whether this is modifiable by platelet transfusion.

Glycocalyx Degradation and Inflammation in Cardiac Surgery.

OBJECTIVE: Experimental inflammation induces degradation of glycocalyx. The authors hypothesized that inflammation is an important determinant of glycocalyx degradation in patients undergoing cardiac surgery with cardiopulmonary bypass (CPB). DESIGN: A prospective observational study. SETTING: Operation theater and intensive care unit of a university hospital. PARTICIPANTS: Two separate prospective patient cohorts. INTERVENTIONS: Blood samples were collected at 5 perioperative time points in the trial cohort (30 patients) and only preoperatively in the preoperative cohort (35 patients). Plasma syndecan-1 (biomarker of glycocalyx degradation), interleukin-6 (IL-6), IL-8, and IL-10 were measured. MEASUREMENTS AND MAIN RESULTS: In the trial cohort, preoperative ranges were as follows: 0.8-198 ng/mL for syndecan-1; 0-902 pg/mL for IL-6; 0-314.9 pg/mL for IL-8, and 0-2,909 pg/mL for IL-10. Seven out of 30 patients were outliers in terms of plasma concentrations of syndecan-1 and all cytokines preoperatively. The increase of syndecan-1 was 2.7-fold, and those of IL-6 and IL-8 were both 2.5-fold. The increase of IL-10 was modest. Plasma syndecan-1 correlated with all cytokines preoperatively (IL-6: R = 0.66, p < 0.001; IL-8: R = 0.67, p = 0.001; IL-10: R = 0.73, p < 0.001) as well as at 6 hours postoperatively (IL-6: R = 0.49, p = 0.006; IL-8: R = 0.43, p = 0.02; IL-10: R = 0.41, p = 0.03) and on the postoperative morning (IL-6: R = 0.57, p = 0.001; IL-8: R = 0.37, p = 0.06; IL-10: R = 0.51, p = 0.005) but not intraoperatively. The preoperative findings of the trial cohort could be confirmed in the preoperative cohort. CONCLUSIONS: In patients undergoing cardiac surgery with CPB, inflammation in terms of proinflammatory cytokines IL-6 and IL-8 and anti-inflammatory cytokine IL-10 is associated with glycocalyx degradation measured as plasma syndecan-1 concentrations.

The focus of temperature monitoring with zero-heat-flux technology (3M Bair-Hugger): a clinical study with patients undergoing craniotomy.

In the noninvasive zero-heat-flux (ZHF) method, deep body temperature is brought to the skin surface when an insulated temperature probe with servo-controlled heating on the skin creates a region of ZHF from the core to the skin. The sensor of the commercial Bair-Hugger ZHF device is placed on the forehead. According to the manufacturer, the sensor reaches a depth of 1-2 cm below the skin. In this observational study, the anatomical focus of the Bair-Hugger ZHF sensor was assessed in pre- and postoperative CT or MRI images of 29 patients undergoing elective craniotomy. Assuming the 2-cm depth from the forehead skin surface, the temperature measurement point preoperatively reached the brain cortex in all except one patient. Assuming the 1-cm depth, the preoperative temperature measurement point did not reach the brain parenchyma in any of the patients and was at the cortical surface in two patients. Corresponding results were obtained postoperatively, although either sub-arachnoid fluid or air was observed in all CT/MRI images. Craniotomy did not have a detectable effect on the course of the ZHF temperatures. In Bland-Altman analysis, the agreement of ZHF temperature with the nasopharyngeal temperature was 0.11 (95% confidence interval - 0.54 to 0.75) °C and with the bladder temperature - 0.14 (- 0.81 to 0.52) °C. As conclusions, within the reported range of the Bair-Hugger ZHF measurement depth, the anatomical focus of the sensor cannot be determined. Craniotomy did not have a detectable effect on the course of the ZHF temperatures that showed good agreement with the nasopharyngeal and bladder temperatures.

Transfusion Threshold of Hemoglobin 80 g/L Is Comparable to 100 g/L in Terms of Bleeding in Cardiac Surgery: A Prospective Randomized Study.

OBJECTIVE: Anemia is common after cardiac surgery and, according to some suggestive evidence, may be associated with increased bleeding, other morbidity, and mortality. However, transfusion of red blood cells (RBC) may cause adverse effects and increase cost. The authors hypothesized that the restrictive hemoglobin threshold (Hb of 80 g/L) may aggravate bleeding more than the higher Hb threshold (Hb 100 g/L). DESIGN: Prospective randomized trial. TYPE OF HOSPITAL: University Hospital of Helsinki, Finland. PARTICIPANTS: Eighty patients with written informed consent, scheduled for elective open-heart surgery were randomized in 2 groups. INTERVENTIONS: Two study groups had RBC transfusion threshold of either Hb 80 g/L or 100 g/L. These triggers were followed for a 24-hour period postoperatively. A medical follow-up was carried out for 7 days after surgery. MEASUREMENTS AND MAIN RESULTS: Rotational thromboelastometry (ROTEM) and conventional laboratory tests were performed to evaluate coagulation. There was no significant difference in bleeding or ROTEM parameters between the groups. Complication rate and Hb concentration after 7-day follow-up were not different between the groups, but Group 100 g/L had received twice the amount of RBC transfusions. CONCLUSION: Hb threshold of 80 g/L for RBC transfusion in cardiac surgery is comparable to 100 g/L in terms of bleeding and possibly short-term complications.

Effect of Albumin in Combination With Mannitol on Whole-blood Coagulation In Vitro Assessed by Thromboelastometry.

BACKGROUND: Albumin and mannitol may interfere with hemostasis, but their coinfluence is unclear. We aimed to determine the effects of albumin alone and in combination with mannitol or Ringer acetate (RAC) on hemostasis in crossover in vitro study. MATERIALS AND METHODS: From citrated fresh whole blood withdrawn from 10 volunteers, we prepared 2.5, 5, 10, 15, and 20 vol% dilutions of 4% albumin (Alb group). Each sample was thereafter diluted by 15% mannitol (Alb/Man group) or RAC (Alb/RAC group) at a ratio of 9:1. Using thromboelastometry, FibTEM (fibrinogen ROTEM) and ExTEM (extrinsic ROTEM) tests were performed. RESULTS: A 20 vol%, but not 2.5 to 15 vol% dilution of albumin caused a prolonged clot formation time, α-angle decrease, and maximum clot firmness (MCF) weakening compared with undiluted sample (P<0.05). Clot formation time prolonged more in Alb5/Man than in Alb5 and Alb5/RAC dilution (P<0.05). In Alb2.5/Man, Alb10/Man, and Alb15/Man, dilution α-angle was lower than in corresponding Alb/RAC and Alb-group dilutions (P<0.05). In ExTEM, MCF decreased similarly in every dilution of Alb/Man and Alb/RAC compared with Alb group (P<0.05). In FibTEM, MCF decreased more in Alb10/Man than in Alb10/RAC dilution (P<0.05). CONCLUSIONS: In up to 15 vol% dilutions, albumin alone did not impair hemostasis in vitro, but in combination with mannitol or RAC coagulation was disturbed similarly at most concentrations. There was some significant additional effect with mannitol at certain concentrations. Our results indicate that coadministration of mannitol and albumin needs further study in vivo.

Incidence of Postoperative Hematomas Requiring Surgical Treatment in Neurosurgery: A Retrospective Observational Study.

OBJECTIVE: We aimed to characterize the occurrence of postoperative hematoma (POH) after neurosurgery overall and according to procedure type and describe the prevalence of possible confounders. METHODS: Patient data between 2010 and 2012 at the Department of Neurosurgery in Helsinki University Hospital were retrospectively analyzed. A data search was performed according to the type of surgery including craniotomies; shunt procedures, spine surgery, and spinal cord stimulator implantation. We analyzed basic preoperative characteristics, as well as data about the initial intervention, perioperative period, revision operation and neurologic recovery (after craniotomy only). RESULTS: The overall incidence of POH requiring reoperation was 0.6% (n = 56/8783) to 0.6% (n = 26/4726) after craniotomy, 0% (n = 0/928) after shunting procedure, 1.1% (n = 30/2870) after spine surgery, and 0% (n = 0/259) after implantation of a spinal cord stimulator. Craniotomy types with higher POH incidence were decompressive craniectomy (7.9%, n = 7/89), cranioplasty (3.6%, n = 4/112), bypass surgery (1.7%, n = 1/60), and epidural hematoma evacuation (1.6%, n = 1/64). After spinal surgery, POH was observed in 1.1% of cervical and 2.1% of thoracolumbar operations, whereas 46.7% were multilevel procedures. 64.3% of patients with POH and 84.6% of patients undergoing craniotomy had postoperative hypertension (systolic blood pressure >160 mm Hg or lower if indicated). Poor outcome (Glasgow Outcome Scale score 1-3), whereas death at 6 months after craniotomy was detected in 40.9% and 21.7%. respectively, of patients with POH who underwent craniotomy. CONCLUSIONS: POH after neurosurgery was rare in this series but was associated with poor outcome. Identification of risk factors of bleeding, and avoiding them, if possible, might decrease the incidence of POH.

Prone Versus Sitting Position in Neurosurgery-Differences in Patients' Hemodynamic Management.

OBJECTIVE: Neurosurgery in general anesthesia exposes patients to hemodynamic alterations in both the prone and the sitting position. We aimed to evaluate the hemodynamic profile during stroke volume-directed fluid administration in patients undergoing neurosurgery either in the sitting or the prone position. METHODS: In 2 separate prospective trials, 30 patients in prone and 28 patients in sitting position were randomly assigned to receive either Ringer acetate (RAC) or hydroxyethyl starch (HES; 130 kDa/0.4) for optimization of stroke volume. After combining data from these 2 trials, 2-way analysis of variance was performed to compare patients' hemodynamic profile between the 2 positions and to evaluate differences between RAC and HES consumption. RESULTS: To achieve comparable hemodynamics during surgery, a higher mean cumulative dose of RAC than HES was needed (679 mL ± 390 vs. 455 mL ± 253; P < 0.05). When fluid consumption was adjusted with weight, statistical difference was lost. Fluid administration did not differ between the prone and sitting position. Mean arterial pressure was lower and cardiac index and stroke volume index were higher over time in patients in the sitting position. CONCLUSIONS: The sitting position does not require excess fluid treatment compared with the prone position. HES is slightly more effective than RAC in achieving comparable hemodynamics, but the difference might be explained by patient weight. With goal-directed fluid administration and moderate use of vasoactive drugs, it is possible to achieve stable hemodynamics in both positions.

Decreased maximum clot firmness in rotational thromboelastometry (ROTEM®) is associated with bleeding during extracorporeal mechanical circulatory support.

BACKGROUND:: We aimed to characterize the coagulation disturbances which may increase the risk of bleeding, thrombosis or death shortly after implantation of an extracorporeal membrane oxygenation (ECMO) or ventricular assist (VAD) device. METHODS:: Antithrombotic treatment was started in 23 VAD and 24 ECMO patients according to the hospital protocol. Additionally, conventional laboratory testing, rotational thromboelastometry (ROTEM®) and platelet function analysis (Multiplate®) were performed at predetermined intervals. RESULTS:: Four out of twenty-four (16.7%) of ECMO patients and 6/23 (26.1%) of VAD patients had severe bleeding after the procedure. When all the patients were analyzed together, low maximum clot firmness (MCF) in ExTEM and FibTEM analyses was associated with severe bleeding (p<0.05) and low MCF in FibTEM with 30-day mortality. Low platelet count and hematocrit levels were also associated with severe bleeding. When VAD and ECMO patients were separated into different groups, the association between ROTEM® parameters, bleeding and survival was found only in limited time points. Four patients with VAD had cerebral ischemia indicative of thromboembolism. However, this had no significant correlation with ROTEM® or Multiplate® parameters. CONCLUSION:: Hypocoagulation shown by ROTEM® was associated with bleeding complications in patients with mechanical circulatory support. In contrast, hypercoagulation did not correlate with clinical thrombosis.

Preoperative identification of neurosurgery patients with a high risk of in-hospital complications: a prospective cohort of 418 consecutive elective craniotomy patients.

OBJECT: Patients undergoing craniotomy are routinely assessed preoperatively, yet the role of these assessments in predicting outcome is poorly studied. This study aimed to identify preoperative factors predicting in-hospital outcome after cranial neurosurgery. METHODS: The study cohort consisted of 418 consecutive adults undergoing elective craniotomy for any intracranial lesion. Apart from the age criteria (≥ 18 years), almost all patients were considered eligible for the study to increase external validity of the results. The studied preoperative assessments included various patient-related data, routine blood tests, American Society of Anesthesiologists (ASA) Physical Status Classification system, and a local modification of the ASA classification (Helsinki ASA classification). Adverse outcomes were in-hospital mortality, in-hospital systemic or infectious complications, and in-hospital CNS deficits. Resource use was defined as length of stay (LOS) in the intensive care unit and overall LOS in the hospital. RESULTS: The in-hospital mortality rate was 1.0%. In-hospital systemic or infectious complications and permanent or transient CNS deficits occurred in 6.7% and 11.2% of the patients, respectively. Advanced age (≥ 60-65 years), elevated C-reactive protein level (> 3 mg/L), and high Helsinki ASA score (Class 4) were associated with in-hospital systemic and infectious complications, and a combination of these could identify one-fourth of the patients with postoperative complications. Moreover, this combination of preoperative assessment parameters was significantly associated with increased resource use. CONCLUSIONS: In this first prospective and unselected cohort study of outcome after elective craniotomy, simple preoperative assessments identified patients with a high risk of in-hospital systemic or infectious complications as well as extended resource use. Presented risk assessment methods may be widely applicable, also in low-volume centers, as they are based on composite predictors and outcome events.

Transfusion Frequency of Red Blood Cells, Fresh Frozen Plasma, and Platelets During Ruptured Cerebral Aneurysm Surgery.

BACKGROUND: The use of blood products after subarachnoid hemorrhage (SAH) is common, but not without controversy. The optimal hemoglobin level in patients with SAH is unknown, and data on perioperative need for red blood cell (RBC), fresh frozen plasma (FFP), or platelet transfusions are limited. We studied perioperative administration of RBCs, FFP, and platelets and the impact of red blood cell transfusions (RBCTs) on outcome in patients undergoing surgery for ruptured a cerebral arterial aneurysm. METHODS: A retrospective analysis was performed of 488 patients with aneurysmal SAH during the years 2006-2009 at Helsinki University Central Hospital. Patients who received RBC, FFP, or platelet concentrates perioperatively were compared with a cohort of patients from the Helsinki database of aneurysmal SAH who did not receive transfusions. A multiple regression model was created to identify factors related to transfusion and outcome. RESULTS: RBC, FFP, or platelet concentrates were given in 7.6% (37 of 488), 3.1% (15 of 488), and 1.2% (6 of 488) of patients intraoperatively and in 3.5% (17 of 486), 1.6% (8 of 488), and 0.9% (4 of 488) of patients postoperatively. Of 37 intraoperative RBCTs, 26 were related to intraoperative rupture of the aneurysm. Intraoperative RBCTs were associated with lower preoperative hemoglobin concentration, higher World Federation of Neurosurgical Societies classification, and intraoperative rupture of an aneurysm. In multivariate analysis, intraoperative RBCT (odds ratio = 5.13, 95% confidence interval = 1.53-17.15), worse World Federation of Neurosurgical Societies classification and Fisher grade (odds ratio = 1.97, confidence interval = 1.64-2.36 and odds ratio = 1.89, confidence interval = 1.23-2.92, respectively), and increasing age (odds ratio = 1.07, confidence interval = 1.04-1.10) independently increased the risk of poor neurologic outcome at 3 months. CONCLUSIONS: Transfusion frequencies of RBCs, FFP, and platelets were relatively low. Intraoperative RBCT was strongly related to intraoperative rupture of the aneurysm in patients with poor-grade SAH. The observed association between poor outcome and RBCT in patients with SAH warrants further study.

Stroke volume-directed administration of hydroxyethyl starch (HES 130/0.4) and Ringer's acetate in prone position during neurosurgery: a randomized controlled trial.

PURPOSE: General anesthesia in the prone position is associated with hypotension. We studied stroke volume (SV)-directed administration of hydroxyethyl starch (HES 130 kDa/0.4) and Ringer's acetate (RAC) in neurosurgical patients operated on in a prone position to determine the volumes required for stable hemodynamics and possible coagulatory effects. METHODS: Thirty elective neurosurgical patients received either HES (n = 15) or RAC (n = 15). Before positioning, SV measured by arterial pressure waveform analysis was maximized by fluid boluses until SV did not increase more than 10 %. SV was maintained by repeated administration of fluid. RAC 3 ml/kg/h was infused in both groups. Thromboelastometry assessed coagulation. Mann­Whitney U test, Wilcoxon signed-rank test, ANOVA on ranks, and a linear mixed model were applied. RESULTS: Comparable hemodynamics were achieved with the mean cumulative (SD) boluses of HES or RAC 240 (51) or 267 (62) ml (P = 0.207) before positioning, 340 (124) or 453 (160) ml (P = 0.039) 30 min after positioning, and 440 (229) or 653 (368) ml at the end of surgery (P = 0.067). The mean dose of basal RAC infusion was 813 (235) and 868 (354) ml (P = 0.620) in the HES and RAC group, respectively. Formation and maximum strength of the fibrin clot were decreased in the HES group. Intraoperative blood loss was comparable between groups (P = 0.861). CONCLUSION: The amount of RAC needed in the prone position was 25 % greater. The cumulative dose of 440 ml HES induced a slight disturbance in fibrin formation and clot strength. We suggest cautious administration of HES during neurosurgery.

Thromboelastometry during intraoperative transfusion of fresh frozen plasma in pediatric neurosurgery.

Normal blood coagulation is essential in pediatric neurosurgery because of the risk of abundant bleeding, and therefore it is important to avoid transfusion of fluids that might interfere negatively with the coagulation process. There is a lack of transfusion guidelines in massive bleeding with pediatric neurosurgical patients, and early use of blood compounds is partly controversial. We describe two pediatric patients for whom fresh frozen plasma (FFP) infusion was started at the early phase of brain tumor surgery to prevent intraoperative coagulopathy and hypovolemia. In addition to the traditional laboratory testing, modified thromboelastometry analyses were used to detect possible disturbances in coagulation. Early transfusion of FFP and red blood cells preserved the whole blood coagulation capacity. Even with continuous FFP infusion, fibrin clot firmness was near to critical value at the end of surgery despite increased preoperative values. By using FFP instead of large amounts of crystalloids and colloids when major blood loss is expected, blood coagulation is probably less likely to be impaired. Our results indicate, however, that the capacity of FFP to correct fibrinogen deficit is limited.

Slack brain in meningioma surgery through lateral supraorbital approach.

BACKGROUND: Surgery of skull base meningiomas by the lateral supraorbital (LSO) approach requires relaxed brain. Therefore, we assessed combined effects of the elements of neuroanesthesia on neurosurgical conditions during craniotomy. METHODS: The anesthesiological and surgical charts of 66 olfactory groove, 73 anterior clinoidal, and 52 tuberculum sellae meningioma patients operated on by the senior author (J.H.) at the Department of Neurosurgery of Helsinki University Central Hospital, Helsinki, Finland, between September 1997 and August 2010, were retrospectively analyzed. RESULTS: One-hundred fifty-four (82%) patients had good surgical conditions, and this was achieved by (1) elevating the head 20 cm above the cardiac level in all patients with only slightly lateral turn or neck flexion, (2) administering mannitol preoperatively in medium or large meningiomas (n = 60), (3) maintaining anesthesia with propofol infusion (n = 46) or volatile anesthetics (n = 107) also in patients with large tumors (n = 37), and (4) controlling intraoperative hemodynamics. Brain relaxation was satisfactory in 18 (10%) and poor in 15 (8%) patients. The median intraoperative blood loss was 200 (range, 0-2000) ml. Only 9% of patients received red blood cell transfusion. The median time to extubation was 18 (range, 8-105) min after surgery. Extubation time correlated with the patients' preoperative clinical status and the size of tumor but not with the modality of anesthesia. CONCLUSIONS: Slack brain during the LSO approach is achieved by correct patient positioning, preoperative mannitol, either by propofol or in small tumors inhaled anesthetics, and optimizing cerebral perfusion pressure. Under these circumstances, intraoperative brain swelling is prevented, bleeding is minimal, and no blood transfusions are needed.

Comparison of hypertonic saline and mannitol on whole blood coagulation in vitro assessed by thromboelastometry.

BACKGROUND: Hypertonic saline (HS) is an alternative to mannitol for decreasing intracranial pressure in traumatic brain injury and before craniotomy. Both HS and mannitol may interfere with blood coagulation but their influence on coagulation has not been compared in controlled situations. Therefore, we evaluated different strengths of HS and 15% mannitol on blood coagulation in vitro. METHODS: Citrated fresh whole blood, withdrawn from 10 volunteers, was diluted with 0.9%, 2.5%, or 3.5% HS or 15% mannitol to make 10 vol.% and 20 vol.% hemodilution in vitro. The diluted blood and undiluted control samples were analyzed with thromboelastometry (ROTEM(®)) using two activators, tissue thromboplastin without (ExTEM(®)) or with cytochalasin (FibTEM(®)). RESULTS: In the FibTEM(®) analysis, maximum clot firmness (MCF) was stronger in the 2.5% HS group than in the mannitol group after both dilutions (P < 0.05). In the ExTEM(®) analysis, clot formation time (CFT) was more delayed in the mannitol group than in the 0.9%, 2.5%, or 3.5% HS groups in 20 vol.% hemodilution (P < 0.05). MCF was weaker in the mannitol group than in the other groups after 20 vol.% dilution (P < 0.05). MCF was also weaker in the 3.5% than in the 0.9% saline group after 20 vol.% dilution (P < 0.05). CONCLUSIONS: Blood coagulation is disturbed more by 15% mannitol than by equiosmolar 2.5% saline. This disturbance seems to be attributed to overall clot formation and strength but also to pure fibrin clot firmness. This saline solution might be more favorable than mannitol before craniotomy in patients with a high risk of bleeding.

Colloid solutions: a clinical update.

Albumin, dextran, gelatin, and hydroxyethyl starch (HES) solutions are colloids that efficiently expand the circulating blood volume. The administration of colloids restores the intravascular volume with minimal risk of tissue edema in comparison with crystalloid solutions alone. However, colloids are always given for surgical and critically ill patients. The type of the colloid, volumes applied, aggressiveness of fluid resuscitation, and the volume status at the initial phase of administration determine their clinical responses. The outcome after fluid resuscitation with various colloids in critically ill patients seems to be comparable according to systematic reviews. A randomized, adequately powered clinical trial comparing modern nonprotein colloid to albumin is still lacking. Rapidly degradable HES solutions have good hemodynamic effects, and the risk of adverse renal and coagulation effects, as well as allergic reactions, is minimal. The current investigation has also shown the beneficial effect of HES solution (especially HES 130/0.4) on inflammatory response, postoperative nausea and vomiting, and postoperative outcome. The indication of colloids with an assessment of the degree of hypovolemia and safety profiles should thus be taken into consideration before colloid administration.

Adenosine-induced cardiac arrest during intraoperative cerebral aneurysm rupture.

BACKGROUND: Rupture of an intracranial aneurysm during surgical clipping may have devastating consequences. Should this happen all methods ought to be considered to stop the bleeding. A short-term cardiac arrest induced by adenosine could be a feasible method to help the surgeon. We present our experiences in the administration of adenosine during an intraoperative aneurysm rupture. METHODS: Medical records of patients who underwent surgical clipping of a cerebral arterial aneurysm were reviewed from 2 university hospitals' operative database in the years 2003 to 2008. Patients were included in this study if adenosine had been administered during intraoperative rupture of an aneurysm. RESULTS: Altogether, 16 of 1014 patients were identified with the use of adenosine during an intraoperative rupture of an aneurysm. All of the patients had sinus rhythm and normotension before the rupture of the aneurysm. Twelve patients were administered a single dose of adenosine and 4 multiple boluses for induction of cardiac arrest; the median (range) total dose was 12 (6-18) mg and 27 (18-87) mg, respectively. The clipping of the aneurysm and the recovery of circulation were uneventful in all cases. In a subgroup analysis according to patient outcome as alive/dead, the pre- and postoperative neurologic condition correlated with the outcome, whereas adenosine did not have any effect on the patient outcome. CONCLUSION: In a case of a sudden aneurysm rupture, adenosine-induced circulatory arrest could be a safe option to facilitate clipping of an aneurysm. However, if adenosine is used, a very close collaboration between the surgeon and the anesthesiologist is required.

Thromboprophylactic management in the neurosurgical patient with high risk for both thrombosis and intracranial bleeding.

PURPOSE OF REVIEW: Pharmacologic thromboprophylaxis is indicated in neurosurgery patients having high risk for venous or arterial thrombosis. The pharmacologic thromboprophylaxis, as well as temporary interruption of antithrombotic drugs because of surgery, and possible use of substitutive medication ('bridging therapy') are reviewed. RECENT FINDINGS: Pharmacologic thromboprophylaxis is used for most neurosurgical patients, but clinical practices vary a lot. There are only few reports of the management of neurosurgery patients having mechanical prosthetic heart valves, atrial fibrillation with comorbidities, history of deep venous thrombosis, thrombophilia, or coronary artery stent. These patients present a high risk for both thrombosis and bleeding as temporary interruption of antithrombotic medication as well as a substitutive medication would be indicated. Generally, the bridging therapy with low-molecular-weight heparin (LMWH) is a feasible approach in patients needing interruption of vitamin K antagonists. Experiences in neurosurgery patients emphasize carefully secured hemostasis and tailored dose as well as timing of LMWH. In patients with a recent coronary artery stent scheduled for neurosurgery, an individualized plan is needed. Bridging therapy for antiplatelet agents or novel oral anticoagulants is not yet settled. SUMMARY: Pharmacologic thromboprophylaxis, or bridging therapy, should be tailored according to the individual risks and the type of neurosurgery. The bleeding risk is likely minimized by allowing coagulation capacity to normalize preoperatively and by using reduced doses of LMWH starting relatively late after neurosurgery.