Effect of Increasing Blood Pressure on Brain Tissue Oxygenation in Adults After Severe Traumatic Brain Injury.

OBJECTIVES: To examine if increasing blood pressure improves brain tissue oxygenation (PbtO2) in adults with severe traumatic brain injury (TBI). DESIGN: Retrospective review of prospectively collected data. SETTING: Level-I trauma center teaching hospital. PATIENTS: Included patients greater than or equal to 18 years of age and with severe (admission Glasgow Coma Scale [GCS] score < 9) TBI who had advanced neuromonitoring (intracranial blood pressure [ICP], PbtO2, and cerebral autoregulation testing). INTERVENTIONS: The exposure was mean arterial pressure (MAP) augmentation with a vasopressor, and the primary outcome was a PbtO2 response. Cerebral hypoxia was defined as PbtO2 less than 20 mm Hg (low). MAIN RESULTS: MAP challenge test results conducted between ICU admission days 1-3 from 93 patients (median age 31; interquartile range [IQR], 24-44 yr), 69.9% male, White (n = 69, 74.2%), median head abbreviated injury score 5 (IQR 4-5), and median admission GCS 3 (IQR 3-5) were examined. Across all 93 tests, a MAP increase of 25.7% resulted in a 34.2% cerebral perfusion pressure (CPP) increase and 16.3% PbtO2 increase (no MAP or CPP correlation with PbtO2 [both R2 = 0.00]). MAP augmentation increased ICP when cerebral autoregulation was impaired (8.9% vs. 3.8%, p = 0.06). MAP augmentation resulted in four PbtO2 responses (normal and maintained [group 1: 58.5%], normal and deteriorated [group 2: 2.2%; average 45.2% PbtO2 decrease], low and improved [group 3: 12.8%; average 44% PbtO2 increase], and low and not improved [group 4: 25.8%]). The average end-tidal carbon dioxide (ETCO2) increase of 5.9% was associated with group 2 when cerebral autoregulation was impaired (p = 0.02). CONCLUSIONS: MAP augmentation after severe TBI resulted in four distinct PbtO2 response patterns, including PbtO2 improvement and cerebral hypoxia. Traditionally considered clinical factors were not significant, but cerebral autoregulation status and ICP responses may have moderated MAP and ETCO2 effects on PbtO2 response. Further study is needed to examine the role of MAP augmentation as a strategy to improve PbtO2 in some patients.

Perioperative Care and Outcomes of Patients with Brain Tumors Undergoing Elective Craniotomy: Experience from an Ethiopian Tertiary-Care Hospital.

OBJECTIVE: To describe patients, perioperative care, and outcomes undergoing supratentorial and infratentorial craniotomy for brain tumor resection in a tertiary-care hospital in Ethiopia. METHODS: A retrospective cohort study of patients consecutively admitted between January 1, 2021, and December 31, 2021, was performed. We characterized patients, perioperative care, and outcomes. RESULTS: The final sample comprised 153 patients; 144 (94%) were 18 years and over, females (n = 48, 55%) with primarily American Society of Anesthesiologists physical class II (n = 97, 63.4%) who underwent supratentorial (n = 114, 75%), or infratentorial (n = 39, 25%) tumor resection. Patients were routinely admitted (95%) to floor/wards before craniotomy; Inhaled anesthetic (isoflurane 88%/halothane 12%) was used for maintenance of general anesthesia. Propofol (n = 93, 61%), mannitol (n = 73, 48%), and cerebrospinal fluid drain (n = 28, 18%), were used to facilitate intraoperative brain relaxation, while the use of hyperventilation was rare (n = 1). The average estimated blood loss was 1040 ± 727 ml; 37 (24%) patients received tranexamic acid, and 57 (37%) received a blood transfusion. Factors associated with extubation were a) infratentorial tumor location: relative risk (RR) 0.45 (95% confidence interval [CI] 0.29-0.69), preoperative hydrocephalus: RR 0.51, (95% CI 0.34-0.79), shorter total anesthesia duration: 277.8 + 8.8 versus 426.77 + 13.1 minutes, P < 0.0001, lower estimated blood loss: 897 + 68 ml versus 1361.7 + 100 ml, P = 0.0002, and cerebrospinal fluid drainage to facilitate brain relaxation: RR 0.52, 95% CI 0.32-0.84). Approximately one in ten patients experienced postoperative obstructive hydrocephalus, surgical site infections, or pneumonia. CONCLUSIONS: These findings suggest that certain factors may impact patient outcomes following craniotomy for tumor resection. By identifying these factors, health care providers may be better equipped to develop individualized treatment plans and improve patient outcomes. Additionally, the study highlights the importance of postoperative monitoring and management to prevent complications.

Utilization of rehabilitation services in violent versus nonviolent traumatic spinal cord injury.

BACKGROUND: Violence is the third leading cause of spinal cord injury (SCI) in the United States, and people with violence-related SCI have worse long-term outcomes compared to other traumatic SCI etiologies. Little is known, however, about the underlying reasons for these differences. Access to and utilization of rehabilitation services may differ in this population, but their outpatient care has not been previously investigated. OBJECTIVE: To evaluate differences in utilization patterns of outpatient rehabilitation services between people with violence-related SCI and other traumatic SCI etiologies. DESIGN: Retrospective cohort study. SETTING: Academic tertiary care hospital system. PATIENTS: A total of 41 patients with violence-related SCI residing in King County at the time of injury who completed inpatient rehabilitation (IPR) in our institution were identified from the hospital trauma registry and matched with 41 control patients with nonviolent traumatic SCI. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE(S): The number of appointments attended, canceled, and missed during the first year after discharge from IPR were obtained by chart review for physical medicine & rehabilitation (PM&R) physicians and therapy services. RESULTS: People with violence-related SCI had decreased follow-up with outpatient rehabilitation services after IPR discharge compared to non-violent traumatic SCI, including PM&R (2.50 ± 2.44 vs. 3.76 ± 2.21 visits, ß = -1.28, p = .017), physical therapy (8.91 ± 11.02 vs. 17.57 ± 15.26, ß = -9.79, p = .009), occupational therapy (4.28 ± 7.90 vs. 10.04 ± 14.42, ß = -6.18, p = .033), and recreational therapy (0.293 ± 0.955 vs. 1.37 ± 2.86, ß = -1.07, p = .035). The rate of missed appointments was also higher among people with violence-related SCI compared to controls for PM&R (25.2% ± 28.5% vs. 9.9% ± 16.5%, ß = 14.6%, p = .014) and physical therapy (26.0% ± 32.0% vs 4.2% ± 13.2%, ß = 22.1%, p = .009). CONCLUSIONS: Individuals with violence-related SCI had fewer follow-up appointments with PM&R physicians and other allied health professionals and were more likely to miss scheduled appointments compared to other traumatic SCI etiologies. Decreased outpatient follow-up may affect long-term outcomes for people with violence-related SCI.

Critical Care Experience With Clinical Cerebral Autoregulation Testing in Adults With Traumatic Brain Injury.

BACKGROUND: To describe the setting, feasibility, and safety of static cerebral autoregulation testing in critically injured adults with traumatic brain injury (TBI).  Methods: We reviewed static autoregulation testing using transcranial Doppler (TCD) ultrasound in patients > 18 years with TBI ICD codes between January 1, 2014, and December 31, 2021. Adverse events during testing were defined as systemic hypertension (systolic blood pressure (SBP>180 mmHg), bradycardia (HR<40 bpm), and high ICP (>30 mmHg). Impaired and absent cerebral autoregulation was defined as an autoregulatory index (ARI) <0.4 and ARI 0, respectively. We characterized prescribed changes in intracranial pressure (ICP) and cerebral perfusion pressure (CPP) targets by autoregulation testing results.  Results: A total of 135 patients, median age 31 (interquartile range (IQR) 24, 43) years, 71.9% male, admission Glasgow coma scale (GCS) score 3 (IQR 3, 5.5), and 70.9% with subdural hematoma from severe (GCS 3-8; 133 (98.5%)) and moderate (GCS 9-12; 2 (1.5%)) TBI, underwent 309 attempted testing. All patients were mechanically ventilated and had ICP monitoring; 246 (80%) had brain tissue oxygen monitoring, and 68 (22%) had an external ventricular drain. The median number of autoregulation tests was two (range 1-3) tests/patient, and the median admission to the first test time was two days (IQR 1, 3). Of 55 (17.8%) tests not completed, systemic hypertension (32, 10.4%), intracranial hypertension (10, 3.2%), and bradycardia (3, 0.9%) were transient. Fifty-three (51%) of the first (n=104) autoregulation tests showed impaired/absent cerebral autoregulation. Impaired/absent autoregulation results at the first test were associated with repeat cerebral autoregulation testing (RR 2.25, 95% CI [1.40-3.60], p=0.0007) than intact cerebral autoregulation results. Pre-testing cerebral hemodynamic targets were maintained (n=131; 86.8%) when cerebral autoregulation was impaired (n=151; RR 1.49, 95% CI [1.25-1.77], p<0.0001). However, 15 (9.9%) test results led to higher ICP targets (from 20 mmHg to 25 mmHg), 5 (3.3%) results led to an increase in CPP target (from 60 mmHg to 70 mmHg), and five out of 131 (3.8%) patients underwent decompressive craniectomy and placement of an external ventricular drain. Intact cerebral autoregulation results (n=43/103, 41.7%) were associated with a change in ICP targets from 20 mmHg to 25 mmHg (RR 3.15, 95% CI [1.97-5.03], p<0.0001).  Conclusions: Static cerebral autoregulation testing was feasible, safe, and useful in individualizing the care of patients with moderate-severe TBI receiving multimodal neuromonitoring. Testing results guided future testing, cerebral hemodynamic targets, and procedural decisions. Impaired cerebral autoregulation was very common.

Age, admission platelet count, and mortality in severe isolated traumatic brain injury: A retrospective cohort study.

BACKGROUND: We asked whether patients >50 years of age with acute traumatic brain injury (TBI) present with lower platelet counts and whether lower platelet counts are independently associated with mortality. METHODS: We combined trauma registry and laboratory data on a retrospective cohort of all patients ≥18 years of age admitted to our Level 1 US regional trauma center 2015-2021 with severe (Head Abbreviated Injury Score [AIS] ≥3), isolated (all other AIS <3) TBI who had a first platelet count within 1 h of arrival. Age and platelet count were assessed continuously and as groups (age 18-50 vs. >50, platelet normals, and at conventional transfusion thresholds). Outcomes such as mean admission platelet counts and in-hospital mortality were assessed categorically and with logistic regression. RESULTS: Of 44,056 patients, 1298 (3%, median age: 52 [IQR 33,68], 76.1% male) met all inclusion criteria with no differences between younger and older age groups for (ISS; 18 [14,26] vs. 17 [14,26], p = .22), New ISS (NISS; 29 [19,50] vs. 28 [17,50], p = .36), or AIS-Head (4 [3,5] vs. 4 [3,5]; p = .87). Patients aged >50 had lower admission platelet counts (219,000 ± 93,000 vs. 242,000 ± 76,000/µL; p < .001) and greater in-hospital mortality (24.5% vs. 15.6%, p < .001) than those 18-50. In multivariable regression, firearms injuries (OR9.08), increasing age (OR1.004), NISS (OR1.007), and AIS-Head (OR1.05), and decreasing admission platelet counts (OR0.998) were independently associated with mortality (p < .001-.041). Platelet transfusion in the first 4 h of care was more frequent among older patients (p < .001). CONCLUSIONS: Older patients with TBI had lower admission platelet counts, which were independently associated with greater mortality.

Bacterial Brain Abscess and Life-Threatening Intracranial Hypertension Requiring Emergent Decompressive Craniectomy After SARS-CoV-2 Infection in a Healthy Adolescent.

Acute coronavirus 2 (SARS-CoV-2) infection usually results in mild symptoms, but secondary infections after SARS-CoV-2 infection can occur, particularly with comorbid conditions. We present the clinical course of a healthy adolescent with a brain abscess and life-threatening intracranial hypertension requiring emergent decompressive craniectomy after a SARS-CoV-2 infection. A 13-year-old healthy immunized male presented with invasive frontal, ethmoid, and maxillary sinusitis and symptoms of lethargy, nausea, headache, and photophobia due to a frontal brain abscess diagnosed three weeks after symptoms and 11 days of oral amoxicillin treatment. Coronavirus disease 2019 (COVID-19) reverse transcription-polymerase chain reaction (RT-PCR) was negative twice but then positive on amoxicillin day 11 (symptom day 21), when magnetic resonance imaging revealed a 2.5-cm right frontal brain abscess with a 10-mm midline shift. The patient underwent emergent craniotomy for right frontal epidural abscess washout and functional endoscopic sinus surgery with ethmoidectomy. On a postoperative day one, his neurological condition showed new right-sided pupillary dilation and decreased responsiveness. His vital signs showed bradycardia and systolic hypertension. He underwent an emergent decompressive craniectomy for signs of brain herniation. Bacterial PCR was positive for Streptococcus intermedius, for which he received intravenous vancomycin and metronidazole. He was discharged home on hospital day 14 without neurological sequelae and future bone flap replacement. Our case highlights the importance of timely recognition and treatment of brain abscess and brain herniation in patients with neurological symptoms after SARS-CoV-2 infection, even in otherwise healthy patients.

Experience with clinical cerebral autoregulation testing in children hospitalized with traumatic brain injury: Translating research to bedside.

Objective: To report our institutional experience with implementing a clinical cerebral autoregulation testing order set with protocol in children hospitalized with traumatic brain injury (TBI). Methods: After IRB approval, we examined clinical use, patient characteristics, feasibility, and safety of cerebral autoregulation testing in children aged <18 years between 2014 and 2021. A clinical order set with a protocol for cerebral autoregulation testing was introduced in 2018. Results: 25 (24 severe TBI and 1 mild TBI) children, median age 13 years [IQR 4.5; 15] and median admission GCS 3[IQR 3; 3.5]) underwent 61 cerebral autoregulation tests during the first 16 days after admission [IQR1.5; 7; range 0-16]. Testing was more common after implementation of the order set (n = 16, 64% after the order set vs. n = 9, 36% before the order set) and initiated during the first 2 days. During testing, patients were mechanically ventilated (n = 60, 98.4%), had invasive arterial blood pressure monitoring (n = 60, 98.4%), had intracranial pressure monitoring (n = 56, 90.3%), brain-tissue oxygenation monitoring (n = 56, 90.3%), and external ventricular drain (n = 13, 25.5%). Most patients received sedation and analgesia for intracranial pressure control (n = 52; 83.8%) and vasoactive support (n = 55, 90.2%) during testing. Cerebral autoregulation testing was completed in 82% (n = 50 tests); 11 tests were not completed [high intracranial pressure (n = 5), high blood pressure (n = 2), bradycardia (n = 2), low cerebral perfusion pressure (n = 1), or intolerance to blood pressure cuff inflation (n = 1)]. Impaired cerebral autoregulation on first assessment resulted in repeat testing (80% impaired vs. 23% intact, RR 2.93, 95% CI 1.06:8.08, p = 0.03). Seven out of 50 tests (14%) resulted in a change in cerebral hemodynamic targets. Conclusion: Findings from this series of children with TBI indicate that: (1) Availability of clinical order set with protocol facilitated clinical cerebral autoregulation testing, (2) Clinicians ordered cerebral autoregulation tests in children with severe TBI receiving high therapeutic intensity and repeatedly with impaired status on the first test, (3) Clinical cerebral autoregulation testing is feasible and safe, and (4) Testing results led to change in hemodynamic targets in some patients.

Minimal effective weight-based dosing of ondansetron to reduce hypotension in cesarean section under spinal anesthesia: a randomized controlled superiority trial.

BACKGROUND: The weight-based dosing of ondansetron to reduce hypotension has never been investigated. The aim of this study is to determine the optimal dose of ondansetron required based on the patient's weight to reduce hypotension following spinal anesthesia for cesarean section. METHODS: In this prospective, triple-blinded, parallel group, randomized controlled trial, a total of 228 pregnant women were randomized to receive either normal saline (group NS) or ondansetron 0.05 mg/kg (group O1) or ondansetron 0.1 mg/kg (group O2) intravenously 5 min before induction of spinal anesthesia. The incidence of hypotension, mean arterial pressure, heart rate, vasopressor requirements, and blood loss between the three groups were compared. Maternal and neonatal complications were also assessed. Changes in blood pressure and heart rate were compared using the generalized estimating equations method. RESULTS: Thirteen patients were excluded from the analysis because of no intervention (n = 12) and protocol violation (n = 1). Two hundred and fifteen patients remained for the intention-to-treat analysis. The incidence of hypotension in groups NS (n = 72), O1 (n = 71), and O2 (n = 72) were 81.9%, 84.5%, and 73.6%, respectively (P = 0.23). The episodes of hypotension before delivery (first 14 min after spinal anesthesia) were significantly higher in group O1 compared to NS (5 vs 2, P = 0.02). The overall heart rates throughout the operations were not different among the three groups. The ephedrine requirements and amount of blood loss were also similar among the three groups. The metoclopramide requirement was significantly lower in group O2 compared to group NS (2.8% vs 16.7%, P = 0.01). There were no serious adverse events in terms of maternal or neonatal complications. CONCLUSIONS: Ondansetron 0.05 mg/kg or 0.1 mg/kg administered before spinal anesthesia did not reduce the incidence of hypotension in this study. TRIAL REGISTRATION: Thai Clinical Trials Registry, TCTR 20160323001 , 22 March 2016.