Studies on hemodynamics and coagulation in neuroanesthesia

The main goals of neuroanesthesia are to maintain adequate cerebral perfusion pressure (CPP) and, consequently, cerebral blood flow (CBF) to guarantee sufficient oxygenation of the brain and to provide good surgical conditions for the neurosurgeon. This thesis aimed to examine critical aspects of neuroanesthesia with regard to CBF, CPP, blood coagulation, and transfusion of blood products. In our material the requirement of intraoperative blood product transfusion was low during surgery for ruptured arterial aneurysm. Intraoperative red blood cell transfusion (RBCT) seems to be preemptive in nature according to the hemoglobin levels prior to transfusion. RBCT is associated with intraoperative rupture of an aneurysm. Intraoperative RBCT may itself worsen SAH patients neurological outcome. In the event of sudden intraoperative rupture of an aneurysm, adenosine-induced asystole can be used to stop the bleeding and facilitate clipping of the aneurysm. Early infusion of fresh frozen plasma instead of crystalloids should be considered to compensate for expected excess bleeding in neurosurgery to preserve normal coagulation capacity. The potentially less harmful effect of hypertonic saline (HS), relative to mannitol, on blood coagulation may shift the decision towards HS when choosing an optimal solution for treatment of elevated ICP or brain swelling, at least when excess bleeding occurs. However, the clinical relevance of this finding remains unclear and warrants further study. Reliability of end-tidal concentration of carbon dioxide (EtCO2) as an estimate of arterial carbon dioxide partial pressure (PaCO2) after anesthesia induction is not adequate, as seen in the correlation between a decrease in mean arterial pressure and EtCO2-PaCO2 difference in our study. Optimal ventilation after induction of anesthesia should be confirmed by arterial blood gas analysis in patients undergoing neurosurgery to prevent a potentially harmful increase in PaCO2, and consequently, in CBF. Anesthesia in both sitting and prone positions is associated with changes in blood pressure and cardiac function. However, preemptive goal-directed therapy with either Ringer s acetate or hydroxyethyl starch (HES) solutions before positioning enables a stable hemodynamic state during neurosurgery in both positions. The fluid requirement did not differ between the two positions. Slightly less HES is needed to achieve comparable hemodynamics, but is it questionable whether this advantage outweighs the recent concerns regarding colloid safety.Neuroanestesiologian tärkein tavoite on ylläpitää aivojen riittävä perfuusiopaine ja verenvirtaus, jotka takaavat aivojen aineenvaihdunnan edellyttämän hapentarjonnan. Lisäksi neuroanestesiologisilla keinoilla voidaan taata hyvät neurokirurgiset leikkausolosuhteet. Tämän väitöskirjan tarkoituksena oli kuvata ja selvittää aivojen perfuusiopaineeseen sekä veren hyytymiseen ja verensiirtoihin vaikuttavia kliinisiä osatekijöitä neurokirurgisilla potilailla. Verensiirtojen tarve aneurysmaattisen subaraknoidaalivuodon saaneilla leikkauspotilailla oli aineistossamme vähäinen. Punasolujen anto on luonteeltaan ennakoivaa, koska potilaat eivät olleet aneemisia ennen siirtoja ja siirto näyttää liittyvän usein leikkauksen aikaiseen aneurysman puhkeamiseen. Punasolujen siirto saattaa itsenäisesti heikentää näiden potilaiden neurologista toipumista. Aneurysman alkaessa vuotaa leikkauksen aikana voidaan vuoto tyrehdyttää pysäyttämällä sydän lyhytaikaisesti adenosiinilla. Jääplasman antoa tulisi harkita ns. kirkkaiden liuosten sijaan massiivin verenvuodon aikana jo varhaisessa vaiheessa, jotta veren hyytymisominaisuudet säilyisivät mahdollisimman hyvinä. Korkean kallonsisäisen paineen hoitoon käytetyistä liuoksista hypertoninen keittosuola saattaa häiritä veren hyytymistä vähemmän kuin mannitoli. Tämän löydöksen kliininen merkitys vaatii jatkotutkimuksia. Ulostulevan hengityksen hiilidioksidi osapaine ei ole riittävän luotettava mittausmetodi arvioimaan veren hiilidioksidiosapainetta neurokirurgisilla potilailla, koska verenpaineen muutos vaikuttaa näiden kahden arvon erotukseen. Anestesiassa olevan potilaan ventilaation riittävyys tulee vahvistaa verikaasuanalyysillä, jotta veren hiilidioksidiosapaineen nousu ja sitä kautta aivojen verenvirtauksen mahdollisesti haitallinen nousu voidaan estää. Sekä istuvan että vasta-asennossa olevan potilaan anestesiaan liittyy muutoksia potilaan verenpaineessa ja sydämen pumppausvoimassa. Tavoiteohjatulla nestehoidolla, joko Ringerin liuosta tai HES-liuosta käyttäen, voidaan kuitenkin saavuttaa tasainen hemodynamiikka molemmissa leikkausasennoissa. Leikkausasentojen välillä ei ollut eroa tarvittavan nesteen määrässä. Hiukan vähäisemmän HES-liuoksen tarpeen kliininen merkitys on kyseenalainen

Elinluovuttajan hoito - kliinikon vinkkejä

Teema : elinsiirrotElinluovuttajan hoidossa pyritään huolehtimaan irrotettavien elinten elinkelpoisuudesta turvaamalla niiden riittävä verenkierto ja hapentarjonta. Elinluovuttajan hoidosta on olemassa kansalliset hoito-ohjeet. Tässä artikkelissa käydään läpi muutamia elinluovuttajaan hoitoon liittyviä keskeisiä asioita

Incidence and Associated Factors of Anemia in Patients with Acute Moderate and Severe Traumatic Brain Injury

Background Anemia might contribute to the development of secondary injury in patients with acute traumatic brain injury (TBI). Potential determinants of anemia are still poorly acknowledged, and reported incidence of declined hemoglobin concentration varies widely between different studies. The aim of this study was to investigate the incidence of severe anemia among patients with moderate to severe TBI and to evaluate patient- and trauma-related factors that might be associated with the development of anemia. Methods This retrospective cohort study involved all adult patients admitted to Tampere University Hospital's emergency department for moderate to severe TBI (August 2010 to July 2012). Detailed information on patient demographics and trauma characteristics were obtained, including data on posttraumatic care, data on neurosurgical procedures, and all measured in-hospital hemoglobin values. Severe anemia was defined as a hemoglobin level less than 100 g/L. Both univariate and multivariable analyses were performed, and hemoglobin trajectories were created. Results The study included 145 patients with moderate to severe TBI (male 83.4%, mean age 55.0 years). Severe anemia, with a hemoglobin level less than 100 g/L, was detected in 66 patients (45.5%) and developed during the first 48 h after the trauma. In the univariate analysis, anemia was more common among women (odds ratio [OR] 2.84; 95% confidence interval [CI] 1.13-7.15), patients with antithrombotic medication prior to trauma (OR 3.33; 95% CI 1.34-8.27), patients with cardiovascular comorbidities (OR 3.12; 95% CI 1.56-6.25), patients with diabetes (OR 4.56; 95% CI 1.69-12.32), patients with extracranial injuries (OR 3.14; 95% CI 1.69-12.32), and patients with midline shift on primary head computed tomography (OR 2.03; 95% CI 1.03-4.01). In the multivariable analysis, midline shift and extracranial traumas were associated with the development of severe anemia (OR 2.26 [95% CI 1.05-4.48] and OR 4.71 [95% CI 1.74-12.73], respectively). Conclusions Severe anemia is common after acute moderate to severe TBI, developing during the first 48 h after the trauma. Possible anemia-associated factors include extracranial traumas and midline shift on initial head computed tomography.Peer reviewe

Transition of a Clinical Practice to Use of Subdural Drains after Burr Hole Evacuation of Chronic Subdural Hematoma : The Helsinki Experience

BACKGROUND: A number of randomized controlled trials have shown the benefit of drain placement in the operative treatment of chronic subdural hematoma (CSDH); however, few reports have described real-life results after adoption of drain placement into clinical practice. We report the results following a change in practice at Helsinki University Hospital from no drain to subdural drain (SD) placement after burr hole craniostomy for CSDH. METHODS: We conducted a retrospective observational study of consecutive patients undergoing burr hole craniostomy for CSDH. We compared outcomes between a 6-month period when SD placement was arbitrary (Julye December 2015) and a period when SD placement for 48 hours was routine (July-December 2017). Our primary outcome of interest was recurrence of CSDH necessitating reoperation within 6 months. Patient outcomes, infections, and other complications were assessed as well. RESULTS: A total of 161 patients were included, comprising 71 (44%) in the drain group and 90 (56%) in the non-drain group. There were no significant differences in age, comorbidities, history of trauma, or use of antithrombotic agents between the 2 groups (P > 0.05 for all). Recurrence within 6 months occurred in 18% of patients in the non-drain group, compared with 6% in the drain group (odds ratio, 0.28; 95% confidence interval, 0.09-0.87; P = 0.028). There were no differences in neurologic outcomes (P = 0.72), mortality (P = 0.55), infection rate (P = 0.96), or other complications (P = 0.20). CONCLUSIONS: The change in practice from no drain to use of an SD after burr hole craniostomy for CSDH effectively reduced the 6-month recurrence rate with no effect on patient outcomes, infections, or other complications.Peer reviewe

Neurointensive care results and risk factors for unfavorable outcome in aneurysmatic SAH : a comparison of two age groups

Background The mean age of actively treated subarachnoid hemorrhage (SAH) patients is increasing. We aimed to compare outcomes and prognostic factors between older and younger SAH patients. Methods A retrospective single-center analysis of aneurysmal SAH patients admitted to a neuro-ICU during 2014-2019. We defined older patients as >= 70 years and younger patients asPeer reviewe

Intensive care of traumatic brain injury and aneurysmal subarachnoid hemorrhage in Helsinki during the Covid-19 pandemic

Background To ensure adequate intensive care unit (ICU) capacity for SARS-CoV-2 patients, elective neurosurgery and neurosurgical ICU capacity were reduced. Further, the Finnish government enforced strict restrictions to reduce the spread. Our objective was to assess changes in ICU admissions and prognosis of traumatic brain injury (TBI) and aneurysmal subarachnoid hemorrhage (SAH) during the Covid-19 pandemic. Methods Retrospective review of all consecutive patients with TBI and aneurysmal SAH admitted to the neurosurgical ICU in Helsinki from January to May of 2019 and the same months of 2020. The pre-pandemic time was defined as weeks 1-11, and the pandemic time was defined as weeks 12-22. The number of admissions and standardized mortality rates (SMRs) were compared to assess the effect of the Covid-19 pandemic on these. Standardized mortality rates were adjusted for case mix. Results Two hundred twenty-four patients were included (TBIn= 123, SAHn= 101). There were no notable differences in case mix between TBI and SAH patients admitted during the Covid-19 pandemic compared with before the pandemic. No notable difference in TBI or SAH ICU admissions during the pandemic was noted in comparison with early 2020 or 2019. SMRs were no higher during the pandemic than before. Conclusion In the area of Helsinki, Finland, there were no changes in the number of ICU admissions or in prognosis of patients with TBI or SAH during the Covid-19 pandemic.Peer reviewe

Aikuisten krooninen subduraalihematooma

Vertaisarvioitu. English summaryKrooninen kovakalvonalainen verenpurkauma eli subduraalihematooma on yleinen neurokirurgista hoitoa vaativa sairaus. Sitä tulisi epäillä etenkin iäkkäillä potilailla, joiden yleistila on selittämättömästi heikentynyt. Taustalla on usein pään lievä vamma, joka johtaa hiljalleen kertyvään siltalaskimovuotoon kovakalvon ja lukinkalvon väliin. Merkittävimpiä riskitekijöitä ovat ikä, pään vamma, miessukupuoli, alkoholin liikakäyttö, antitromboottinen lääkitys, aivoatrofia ja kallonsisäisen toimenpiteen jälkitila. Tyypillisesti oireet ilmenevät viikkojen kuluttua, kun laajeneva hematooma alkaa painaa aivokudosta. Oireita ovat tasapainovaikeus, raajaheikkous, yleistilan heikkeneminen, päänsärky, sekavuus, puhehäiriö, muistin huononeminen, väsymys tai epileptinen kohtaus. Hoitona tehdään kallonporausleikkaus eli tre-panaatio, jossa hematooma purkautuu ulos. Varhainen diagnoosi ennustaa hyvää hoitotulosta. Etenkin iäkkäillä potilailla kuolleisuus vuoden sisällä on varsin suuri.Krooninen kovakalvonalainen verenpurkauma eli subduraalihematooma on yleinen neurokirurgista hoitoa vaativa sairaus. Sitä tulisi epäillä etenkin iäkkäillä potilailla, joiden yleistila on selittämättömästi heikentynyt. Taustalla on usein pään lievä vamma, joka johtaa hiljalleen kertyvään siltalaskimovuotoon kovakalvon ja lukinkalvon väliin. Merkittävimpiä riskitekijöitä ovat ikä, pään vamma, miessukupuoli, alkoholin liikakäyttö, antitromboottinen lääkitys, aivoatrofia ja kallonsisäisen toimenpiteen jälkitila. Tyypillisesti oireet ilmenevät viikkojen kuluttua, kun laajeneva hematooma alkaa painaa aivokudosta. Oireita ovat tasapainovaikeus, raajaheikkous, yleistilan heikkeneminen, päänsärky, sekavuus, puhehäiriö, muistin huononeminen, väsymys tai epileptinen kohtaus. Hoitona tehdään kallonporausleikkaus eli trepanaatio, jossa hematooma purkautuu ulos. Varhainen diagnoosi ennustaa hyvää hoitotulosta. Etenkin iäkkäillä potilailla kuolleisuus vuoden sisällä on varsin suuri.Peer reviewe

Perioperative Treatment of Brain Arteriovenous Malformations Between 2006 and 2014: The Helsinki Protocol

We reviewed retrospectively the perioperative treatment of microsurgically resected brain arteriovenous malformations (bAVMs) at the neurosurgical department of Helsinki University Hospital between the years 2006 and 2014. We examined the performance of the treatment protocol and the incidence of delayed postoperative hemorrhage (DPH).Peer reviewe

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.Peer reviewe