Reversible focal intracranial hypertension swine model with continuous multimodal neuromonitoring.

BACKGROUND: Intracranial hypertension (HI) is associated with worse neurological outcomes and higher mortality. Although there are several experimental models of HI, in this article we present a reproducible, reversible, and reliable model of intracranial hypertension, with continuous multimodal monitoring. NEW METHOD: A reversible intracranial hypertension model in swine with multimodal monitoring including intracranial pressure, arterial blood pressure, heart rate variation, brain tissue oxygenation, and electroencephalogram is developed to understand the relationship of ICP and EEG. By inflating and deflating a balloon, located 20 mm anterior to the coronal suture and a 15 mm sagittal suture, we generate intracranial hypertension events and simultaneously measure intracranial pressure and oxygenation in the contralateral hemisphere and the EEG, simulating the usual configuration in humans. RESULTS: We completed 5 experiments and in all of them, we were able to complete at least 6 events of intracranial hypertension in a stable and safe way. For events of 20-40 mmHg of ICP we need an median (IQR) of 4.2 (3.64) ml of saline solution into the Foley balloon, a median (IQR) infusion time of 226 (185) second in each event and for events of 40-50 mmHg of ICP we need a median (IQR) of 5.1 (4.66) ml of saline solution, a median (IQR) infusion time of 280 (48) seconds and a median (IQR). The median (IQR) maintenance time was 352 (77) seconds and 392 (166) seconds for 20-40 mmHg and 40-50 mmHg of ICP, respectively. COMPARISON WITH EXISTING METHOD(S): Existing methods do not include EEG measures and do not present the reversibility of intracranial hypertension. CONCLUSIONS: Our model is fully reproducible, it is capable of generating reversible focal intracranial hypertension through strict control of the injected volume, it is possible to generate different infusion rates of the volume in the balloon, in order to generate different scenarios, the data obtained are sufficient to determine the brain complacency in real time. and useful for understanding the pathophysiology of ICP and the relationship between ICP (CPP) and EEG.

Heart rate variability follow-up during COVID-19 -a case report.

BACKGROUND: To detect an early increase in the inflammatory response might prove to be vital for mitigating the deleterious effects of the disease over time. CASES: A 52-year-old obese man with moderate asthma and hypertension, who developed COVID-19 and had moderate symptoms, used a wearable device to record heart rate variability (HRV) during his illness. He had low parasympathetic tone, which decreased daily until it reached almost 2 standard deviations (SD) below normal values at the end of the second week. His sympathetic tone increased from > 3 SD to > 5 SD. CONCLUSIONS: Conclusions: These findings suggest an altered modulation of the sympathetic and parasympathetic nervous systems in COVID-19, such that the sympathetic tone is augmented and the parasympathetic tone is reduced. Population norms of COVID-19 infections should be further studied over the short-term and using 24 h HRV measurements.

Critical appraisal of published literature.

With a large output of medical literature coming out every year, it is impossible for readers to read every article. Critical appraisal of scientific literature is an important skill to be mastered not only by academic medical professionals but also by those involved in clinical practice. Before incorporating changes into the management of their patients, a thorough evaluation of the current or published literature is an important step in clinical practice. It is necessary for assessing the published literature for its scientific validity and generalizability to the specific patient community and reader's work environment. Simple steps have been provided by Consolidated Standard for Reporting Trial statements, Scottish Intercollegiate Guidelines Network and several other resources which if implemented may help the reader to avoid reading flawed literature and prevent the incorporation of biased or untrustworthy information into our practice.

Inexpensive video-laryngoscopy guided intubation using a personal computer: initial experience of a novel technique.

Video-laryngoscopy may provide an enhanced view of laryngeal structures compared to direct visualization. Commercial video-laryngoscopes are often expensive, limiting its adoption for routine use. We describe our initial experience using an inexpensive custom made device. Patients >15 years age, were randomly chosen, after informed consent, for video-laryngoscopy. A custom device easily assembled using an USB endoscopic camera, a conventional Macintosh laryngoscope blade size 3 or 4, and a personal computer was used. Patients with Mallampati class 1-3 were chosen. Video-laryngoscopy was recorded and reviewed. Twenty-four patients aged 16-68 years, of mean weight 58.46 ± 12.54 (40-86) kg were studied. The glottis could be visualized and intubation could be performed in all patients with 22/24 patients on first attempt. Mean duration of laryngoscopy was 22.17 ± 12.78 (7-59) s. Time taken for intubation, was mean of 28.58 ± 21.01 (9-89) s. Three patients with anticipated difficult airways could be intubated on the first attempt. Minor blood staining of the airway was seen in the video in two patients. Cormack-Lehane laryngoscopy grade visualized was 1 in 9/24, 2 in 15/24 patients. Percentage of glottic opening score was 62.29 ± 28.40 (20-100) %. Real-time video could be captured in all cases. The custom-made, inexpensive, video-laryngoscopy device is safe and reliable for clinical use. Real-time visualization and endotracheal intubation were successful in all patients, including those with anticipated difficult airway. Further, this device helps in archiving the video of intubation.

Assessment and confirmation of tracheal intubation when capnography fails: a novel use for an USB camera.

A 62 year old male with a right pyriform fossa lesion extending to the right arytenoid and obscuring the glottic inlet was planned for laser assisted excision. Direct laryngoscopic assessment after topicalization of the airway, showed a Cormack Lehane grade 3 view. We report a case where, in the absence of a fiberscope, a novel inexpensive Universal Serial Bus camera was used to obtain an optimal laryngoscopic view. This provided direct visual confirmation of tracheal intubation with a Laser Flex tube, when capnography failed to show any trace. Capnography may not be reliable as a sole indicator of confirmation of correct endotracheal tube placement. Video laryngoscopy may provide additional confirmation of endotracheal intubation.

Idiopathic subglottic stenosis in pregnancy: A deceptive laryngoscopic view.

A 28-year-old lady with term gestation, pre-eclampsia and a vague history of occasional breathing difficulty, on irregular bronchodilator therapy, was scheduled for category 1 lower segment caesarean section in view of foetal distress. A Cormack-Lehane grade 1 direct laryngoscopic view was obtained following rapid sequence induction. However, it was not possible to insert a 7.0 or 6.0 size styleted cuffed tracheal tube in two attempts. Ventilation with a supraglottic device was inadequate. Airway was secured with a 4.0 size microlaryngeal surgery tube with difficulty. Computed tomography scan of the neck following tracheostomy for failed extubation revealed subglottic stenosis (SGS) with asymmetric arytenoid calcification. This report describes the management of a rare case of unrecognised idiopathic SGS in pregnancy.