Diffuse alveolar hemorrhage after hematopoietic cell transplantation- response to treatments and risk factors for mortality

Diffuse alveolar hemorrhage (DAH) is a life-threatening complication of hematopoietic cellular therapy (HCT). This study aimed to evaluate the effect of DAH treatments on outcomes using data from consecutive HCT patients clinically diagnosed with DAH from 3 institutions between January 2018-August 2022. Endpoints included sustained complete response (sCR) defined as bleeding cessation without recurrent bleeding, and non-relapse mortality (NRM). Forty children developed DAH at a median of 56.5 days post-HCT (range 1-760). Thirty-five (88%) had at least one concurrent endothelial disorder, including transplant-associated thrombotic microangiopathy (n=30), sinusoidal obstructive syndrome (n=19), or acute graft versus host disease (n=10). Fifty percent had a concurrent pulmonary infection at the time of DAH. Common treatments included steroids (n=17, 25% sCR), inhaled tranexamic acid (INH TXA,n=26, 48% sCR), and inhaled recombinant activated factor VII (INH fVIIa, n=10, 73% sCR). NRM was 56% 100 days after first pulmonary bleed and 70% at 1 year. Steroid treatment was associated with increased risk of NRM (HR 2.25 95% CI 1.07-4.71, p=0.03), while treatment with INH TXA (HR 0.43, 95% CI 0.19- 0.96, p=0.04) and INH fVIIa (HR 0.22, 95% CI 0.07-0.62, p=0.005) were associated with decreased risk of NRM. Prospective studies are warranted to validate these findings

Method and validation of synaptosomal preparation for isolation of synaptic membrane proteins from rat brain

The ability to isolate and observe molecular changes in protein composition and function at synapses is important in understanding the disease mechanisms. Because signal transmission is highly regulated by transient phosphorylation of neuronal proteins at the synapse, preservation of this protein modification during synaptosome preparation is essential. Therefore, enriched preparations of synaptic particles called synaptosome are necessary to study synapse function. Because of insufficiency of ample sample for quantitative and qualitative analysis via old method, we applied some modifications that were resultant in high synapse yield. Interestingly, we found that modified methods produced more protein as well as more clear protein band on electrophoresis. Therefore, the modified procedure was better than the older method in effort to isolate more pure synapse protein for improved result outcome. To advance the method for our study, the following modifications were made to the regularly used protocols: • The pellet consisting of synaptosomes was cleaned two to three times in HEPES buffer containing proteases inhibitor and centrifuged at 12,000 × g for 15 min each. This step is highly essential to remove any contamination of sucrose-HEPES buffer and other organelle's which interfere with protein purification analysis. • Following this step, the synaptosome pellets were suspended in RIPA buffer (mixed with protease inhibitor and PMSF) along with 0.2% TritonX-100 and further centrifuged at 20,000 × g. • Further, the resulting pellet was discarded and suspended in RIPA buffer (mixed with protease inhibitor and PMSF) only. The sample was immediately used for protein estimation and protein electrophoresis

The Number of Tracheal Intubation Attempts Matters! A Prospective Multi-Institutional Pediatric Observational Study

Background: The impact of multiple tracheal intubation (TI) attempts on outcomes in critically ill children with acute respiratory failure is not known. The objective of our study is to determine the association between number of TI attempts and severe desaturation (SpO2 \u3c 70 %) and adverse TI associated events (TIAEs). Methods: We performed an analysis of a prospective multicenter TI database (National Emergency Airway Registry for Children: NEAR4KIDS). Primary exposure variable was number of TI attempts trichotomized as one, two, or \u3e= 3 attempts. Estimates were adjusted for history of difficult airway, upper airway obstruction, and age. We included all children with initial TI performed with direct laryngoscopy for acute respiratory failure between 7/2010-3/2013. Our main outcome measures were desaturation (\u3c 80 % during TI attempt), severe desaturation (\u3c 70 %), adverse and severe TIAEs (e.g., cardiac arrest, hypotension requiring treatment). Results: Of 3382 TIs, 2080(65 %) were for acute respiratory failure. First attempt success was achieved in 1256/2080(60 %), second attempt in 503/2080(24 %), and \u3e= 3 attempts in 321/2080(15 %). Higher number of attempts was associated with younger age, history of difficult airway, signs of upper airway obstruction, and first provider training level. The proportion of TIs with desaturation increased with increasing number of attempts (1 attempt: 16 %, 2 attempts: 36 %, \u3e= 3 attempts: 56 %, p \u3c 0.001; adjusted OR for 2 attempts: 2.9[95 % CI: 2.3-3.7]; \u3e= 3 attempts: 6.5[95 % CI: 5.0-8.5], adjusted for patient factors). Proportion of TIs with severe desaturation also increased with increasing number of attempts (1 attempt: 12 %, 2 attempts: 30 %, \u3e= 3 attempts: 44 %, p \u3c 0.001); adjusted OR for 2 attempts: 3.1[95 % CI: 2.4-4.0]; \u3e= 3 attempts: 5.7[95 % CI: 4.3-7.5]). TIAE rates increased from 10 to 29 to 38 % with increasing number of attempts (p \u3c 0.001); adjusted OR for 2 attempts: 3.7[95 % CI: 2.9-4.9]; \u3e= 3 attempts: 5.5[95 % CI: 4.1-7.4]. Severe TIAE rates went from 5 to 8 to 9 % (p = 0.008); adjusted OR for 2 attempts: 1.6 [95 % CI: 1.1-2.4]; \u3e= 3 attempts: 1.8[95 % CI: 1.1-2.8]. Conclusions: Number of TI attempts was associated with desaturations and increased occurrence of TIAEs in critically ill children with acute respiratory failure. Thoughtful attention to initial provider as well as optimal setting/preparation is important to maximize the chance for first attempt success and to avoid desaturation

Distinctive effect of anesthetics on the effect of limb remote ischemic postconditioning following ischemic stroke.

Limb remote ischemic postconditioning (LRIP) has been reported as an effective method to reduce the induced experimental stroke damage after ischemic reperfusion (IR) injury. Studies suggest that anesthetics used during induction of ischemic stroke can reduce IR injury, which could affect the actual mechanisms of neuroprotection by LRIP. This study focuses on the comparative effects of anesthetics such as isoflurane and ketamine-xylazine on ischemic injury when used during LRIP. Adult C57BL/6 mice were anesthetized by isoflurane or halothane, and transient middle cerebral artery occlusion (MCAO) was induced through insertion of the filament. Under isoflurane or ketamine-xylazine anesthesia, LRIP was performed after 90 min of reperfusion by carrying out three cycles of 5 min ischemia/5 min reperfusion of the bilateral hind limbs for one session per day for a total of 3 days. Results showed that the use of different anesthetics-isoflurane or ketamine-xylazine-during LRIP had no effects on body weight. However, LRIP was able to improve neurological function as observed by the neurological deficit score in ischemic mice. Interestingly, the neurological deficit in the group where ketamine-xylazine was used was better than the group where isoflurane was used during LRIP. Furthermore, the LRIP was able to prolong the period of the ischemic mice on the rotarod and this effect was more significant in the groups where ketamine-xylazine was used during LRIP. Moreover, LRIP significantly attenuated the infarction volume; however, this effect was independent of the anesthetic used during LRIP. From these results, we conclude that ischemic mice that were subjected to LRIP under ketamine-xylazine anesthesia had better neurological deficit outcomes after stroke

“Difficult to Sedate”: Successful Implementation of a Benzodiazepine-Sparing Analgosedation-Protocol in Mechanically Ventilated Children

We sought to evaluate the success rate of a benzodiazepine-sparing analgosedation protocol (ASP) in mechanically ventilated children and determine the effect of compliance with ASP on in-hospital outcome measures. In this single center study from a quaternary pediatric intensive care unit, our objective was to evaluate the ASP protocol, which included opiate and dexmedetomidine infusions and was used as first-line sedation for all intubated patients. In this study we included 424 patients. Sixty-nine percent (n = 293) were successfully sedated with the ASP. Thirty-one percent (n = 131) deviated from the ASP and received benzodiazepine infusions. Children sedated with the ASP had decrease in opiate withdrawal (OR 0.16, 0.08–0.32), decreased duration of mechanical ventilation (adjusted mean duration 1.81 vs. 3.39 days, p = 0.018), and decreased PICU length of stay (adjusted mean 3.15 vs. 4.7 days, p = 0.011), when compared to the cohort of children who received continuous benzodiazepine infusions. Using ASP, we report that 69% of mechanically ventilated children were successfully managed with no requirement for continuous benzodiazepine infusions. The 69% who were successfully managed with ASP included infants, severely ill patients, and children with chromosomal disorders and developmental disabilities. Use of ASP was associated with decreased need for methadone use, decreased duration of mechanical ventilation, and decreased ICU and hospital length of stay