A clinical photograph of a printed arterial blood gas (ABG) analysis report. The document displays measured and calculated physiological values at a patient temperature of 37.0°C. Key measured values include a pH of 7.480, pCO2 of 22.3 mmHg, pO2 of 330.6 mmHg, and electrolyte levels (Na+ 143.4 mmol/L, K+ 3.28 mmol/L, Ca++ 1.03 mmol/L). Calculated values show a bicarbonate (HCO3-) level of 16.8 mmol/L and an oxygen saturation (SO2%) of 100.0%. This visual demonstrates a 'saturation gap' characteristic of certain toxicological conditions, such as methemoglobinemia, where the calculated oxygen saturation from the ABG appears normal (100%) despite the patient potentially experiencing clinical cyanosis and low peripheral pulse oximetry readings. The image is an educational tool for critical care, emergency medicine, and clinical toxicology, illustrating the interpretation of acid-base balance and oxygenation status.

This medical anatomical diagram illustrates the arterial blood supply and vascular distribution patterns across the internal skull base, specifically focusing on feeders involved in skull base meningiomas. The composite image consists of five sub-figures (A-E) superimposed on a superior view of a human skull model. Sub-figure A depicts the Dorsal Meningeal Artery (DMA) in red, originating from the meningohypophyseal trunk and descending along the upper clivus. Sub-figure B shows the Ascending Pharyngeal Artery (APA) in orange, distributing around the foramen magnum and lower clivus. Sub-figure C highlights the Tentorial Artery (TA) in green, following the course of the tentorium cerebelli. Sub-figure D illustrates the Petrosal Branch (PB) in blue, arising from the middle meningeal artery near the foramen spinosum and reaching the petrous apex. Sub-figure E provides a summarized color-coded overlay demonstrating the spatial relationships of these four vascular territories relative to the clivus, petrous bone, and foramen magnum. This visual guide assists in identifying potential feeding arteries based on the tumor's dural attachment site during preoperative planning for meningioma resection.

Anatomical Diagram and intraoperative overlay illustrating the arterial blood supply to the cavernous sinus, specifically regarding the feeding vessels of skull base meningiomas. The cavernous sinus is highlighted by a pink outline. The arterial distribution is color-coded: the Tentorial Artery (TA) is represented in yellow, demonstrating its supply to the superolateral aspect of the posterior cavernous sinus. The Dural Meningeal Artery (DMA) is shown in blue, highlighting its coverage of the inferomedial portion of the posterior cavernous sinus. A red arrow identifies the interface where cranial nerves are typically situated between these two arterial territories. The image serves as a clinical reference for neurosurgical planning, helping to differentiate between petrotentorial and petroclival meningioma attachments based on their primary feeding arteries and their spatial relationship to critical neurovascular structures within the skull base.

This medical anatomical diagram illustrates the arterial blood supply territories of the human brain through color-coded mapping on axial and coronal sections. Image 'a' displays an axial section at the level of the genu of the corpus callosum, while image 'b' shows a coronal section at the level of the head of the caudate nucleus. The primary vascular territories are identified as follows: red represents the Anterior Cerebral Artery (ACA), supplying the superior and medial aspects; green denotes the Middle Cerebral Artery (MCA), covering the extensive lateral and central regions; and blue indicates the Posterior Cerebral Artery (PCA) territory at the base and posterior aspects. Additionally, smaller vascular zones are identified, including the anterior choroidal artery (purple in 'a', light blue in 'b') and the posterior communicating artery (orange). Blue arrows highlight the border zones or watershed regions between major territories, which are clinically significant as areas highly susceptible to ischemia during hypoperfusion. This visual resource is designed for medical students and clinicians to understand neurovascular anatomy and the pathophysiology of watershed strokes.

A surgical illustration depicting orthotopic renal transplantation, specifically focusing on the arterial clamping technique. The diagram shows the abdominal aorta as a central, vertical cylindrical vessel. A Satinsky surgical clamp is applied to the aorta, positioned precisely at the base of the left renal artery. This selective clamping method is designed to occlude blood flow for the creation of an anastomotic opening (approximately 8 mm from the artery base) while purposefully sparing the mesenteric arteries and the right renal artery, which are visible branching superiorly to the clamped segment. The illustration highlights the relationship between the surgical instrumentation and vascular anatomy to maintain systemic circulation and prevent lower limb or contralateral renal ischemia during the procedure. Key features include the orientation of the clamp jaws relative to the aortic wall and the positioning of the arterial suture lines for donor kidney attachment.

Diagnostic neuroimaging diagram illustrating the setup for Pulsed Arterial Spin Labeling (PASL). The image contains two panels: a sagittal view (left) and a coronal view (right) of the human head and neck, presented as T1-weighted MRI scans. Superimposed on these scans is a large blue rectangular block representing the labeling slice prescription (inversion slab), positioned over the neck region to capture inflowing blood. Within this blue slab, the major feeding arteries (carotid and vertebral arteries) are highlighted in purple, demonstrating the volume where water molecules in the blood are magnetically labeled. A light green horizontal bar is positioned higher across the cerebral cortex, indicating the imaging plane or region where tissue perfusion signal will be measured after a post-labeling delay. Key anatomical landmarks visible include the cervical spine, brainstem, cerebellum, and the base of the skull, showing the spatial relationship between the labeling site in the neck and the target imaging site in the brain. This visual serves as an educational guide for technical MRI protocol positioning in perfusion imaging.

This Comparison Chart displays three coronal PET scan images (a, b, and c) of the human torso, demonstrating the impact of respiratory gating on diagnostic image quality. The modality highlights metabolic activity using a grey scale representing Standardized Uptake Value (SUV) from 0 to 6. Anatomical landmarks include the liver (showing high radiotracer uptake), kidneys, spine, and pulmonary regions. Image (a) shows the scan without motion compensation, where thoracic lesions indicated by arrows appear blurred and elongated along the cranio-caudal axis due to respiratory motion. Image (b) utilizes data-driven quiescent period gating (DDG), and image (c) utilizes externally driven (RPM) quiescent period gating. In both (b) and (c), the motion-compensated images show significantly improved lesion clarity, better definition of lesion morphology, and higher overall image contrast compared to the non-gated image (a). This clinical example illustrates how respiratory gating techniques minimize motion artifacts, particularly for small pulmonary and hilar lesions, enhancing diagnostic accuracy and quantitative SUV measurements in oncology imaging.

Recommendation Table 52. Recommendations for acid-base homeostasis and electrolytes <table><thead><tr><th>Recommendations</th><th>Class^a</th><th>Level^b</th><th>Ref^c</th></tr></thead><tbody><tr><td>Alpha-stat acid-base management should be considered in adult cardiac surgery patients with high-moderate hypothermia due to improved neurological and neurocognitive outcomes.</td><td>IIa</td><td>B</td><td>[786, 787]</td></tr><tr><td>Magnesium sulphate may be considered perioperatively for prophylaxis of postoperative arrhythmias and improved cardiac protection/tissue oxygenation.</td><td>IIb</td><td>B</td><td>[790, 792, 793]</td></tr></tbody></table>

TABLE 2. Treatable Inborn Errors of Metabolism Associated With Global Developmental Delay and Intellectual Disability for Tier 2 Evaluation <table><thead><tr><th>Disorder (Gene)</th><th>Clinical Features (Untreated)</th><th>Biochemical Evaluation</th></tr></thead><tbody><tr><td>Phenylketonuria(PAH)</td><td>Developmental delay/intellectual disability, autism, eczema, reduced skin and hair pigmentation, epilepsy⁴⁸</td><td>Plasma amino acids (increased phenylalanine)</td></tr><tr><td>Classic homocystinuria (CBS1)</td><td>Developmental delay/intellectual disability, marfanoid habitus (tall stature, scoliosis, pectus excavatum), eye lens dislocation and/or high myopia, increased risk of thrombosis⁴⁹</td><td>Total homocysteine (increased), plasma amino acids (increased methionine)</td></tr><tr><td>Organic acidurias</td><td>Developmental delay/intellectual disability, metabolic acidosis, hyperammonemia, failure to thrive, epilepsy, movement disorder, metabolic stroke²⁴</td><td>Urine organic acids, plasma acylcarnitines, ammonia</td></tr><tr><td>Urea cycle disorders</td><td>Episodes of hyperammonemic encephalopathy, protein aversion⁵⁰</td><td>Ammonia, plasma amino acids (abnormal citrulline and/or arginine), urine organic acids (+/− increased orotic acid)</td></tr><tr><td>Creatine deficiency syndromes (AGAT, GAMT, SLC6A8)</td><td>Developmental delay/intellectual disability, autism, epilepsy⁵¹</td><td>Urine creatine/creatinine, plasma creatine, urine and plasma guanidinoacetate</td></tr><tr><td>Lesch-Nyhan syndrome (HPRT1)</td><td>Developmental delay/intellectual disability, autism, spasticity, movement disorder, uric acid nephropathy²⁰</td><td>Plasma uric acid (increased), urine purine and pyrimidines</td></tr><tr><td>Mucopolysaccharidoses</td><td>Developmental delay, behavioral abnormalities, coarse facial features, hepatosplenomegaly, ophthalmological findings, orthopedic anomalies (eg, progressive spine deformities)⁵²</td><td>Urine glycosaminoglycans</td></tr><tr><td>Biotinidase deficiency</td><td>Developmental delay/regression, hypotonia, ataxia, epilepsy, hearing and vision loss, skin rash, alopecia⁵³</td><td>Biotinidase enzyme activity (if not included on newborn screening or clinical suspicion)</td></tr></tbody></table>

A clinical photograph illustrating a specialized human body experiment architecture for respiratory motion compensation during medical imaging or radiation therapy. The setup is mounted on a Somatom Emotion Duo CT scanner couch and includes several numbered components for immobilization and signal acquisition. A: Target simulator for reproducing respiratory displacement; B: Respiratory compensating system (RSS); C: Body fix base; D: Hip fix for lower body stabilization; E: Custom thermoplastic cast used for precise patient immobilization. For signal acquisition, a strain gauge (F) is placed over the abdominal region, held by an arch-type fixture (G) and connected via a compression rod (H). This arrangement translates the physical movement of the abdomen during respiration into voltage signals. The system is designed to synchronize couch movement with the patient's breathing cycle to offset respiratory motion, ensuring more accurate diagnostic imaging or targeted dose delivery in radiation oncology.

This composite educational image illustrates the clinical and diagnostic features of distal renal tubular acidosis (dRTA) associated with sensorineural hearing loss. (a) Data table showing results of a bicarbonate loading test, characterized by low urine-to-blood pCO2 gradient and positive urinary anion gap. (b) Renal ultrasound images of the left and right kidneys demonstrating medullary nephrocalcinosis, visualized as multiple hyperechoic foci within the renal pyramids. (c) Axial FIESTA (Fast Imaging Employing Steady-state Acquisition) cerebral MRI scan showing bilateral enlargement of the endolymphatic sacs (indicated by white arrows), a common finding in Pendred syndrome or dRTA with hearing loss. (d) Anatomical schematic of the inner ear, labeling the cochlea, vestibule, semicircular ducts, and endolymphatic duct. (e) Audiogram plot showing frequency (kHz) versus decibels (dB), depicting significant hearing impairment. The collection integrates metabolic laboratory data, diagnostic radiology (ultrasound and MRI), and functional audiological testing to present a comprehensive case of a hereditary renal-otological syndrome.

This diagnostic image is an axial Fluid-Attenuated Inversion Recovery (FLAIR) magnetic resonance imaging (MRI) scan of the brain. The image demonstrates prominent, symmetrical hyperintensities localized within the bilateral basal ganglia, specifically involving the putamina (indicated by white arrows). Additionally, a smaller, heterogeneous area of increased signal intensity is visible in the anterior midline of the cerebral parenchyma. These visual findings are characteristic of bilateral putaminal necrosis, often associated with acute toxic metabolic encephalopathy, such as methanol poisoning. The image highlights key radiological features used in neuroradiology for identifying toxic insults to the deep gray matter structures. It serves as an educational example for medical students and clinicians in identifying specific imaging patterns related to systemic toxicity and high-anion gap metabolic acidosis.

This pathophysiology diagram illustrates the cellular mechanism by which acidosis regulates MondoA transcriptional activity. The schematic is divided into two comparative states: 'Control' (blue background) and 'Acidosis' (red background). Key components include a mitochondrion, Hexokinase 2 (HK2), the MondoA protein, and metabolic intermediates glucose and glucose-6-phosphate (G6P). Under control conditions, mitochondrial ATP (mtATP) levels are low, and HK2 is bound to the outer mitochondrial membrane. Glucose is converted to G6P by HK2, resulting in basal MondoA interaction. In the 'Acidosis' state, a shift in pH drives a significant increase in mtATP production. This high mtATP concentration facilitates enhanced HK2 enzymatic activity at the mitochondrial surface, leading to increased production of G6P. The elevated G6P levels trigger MondoA to undergo nuclear localization and increased transcriptional activity, as indicated by a large upward arrow toward the nucleus. This diagram demonstrates how metabolic sensing of mitochondrial energy charge and cytoplasmic glucose levels are integrated via HK2 to control gene expression under conditions of metabolic stress or altered pH.

This composite educational image illustrates the physiological and radiological impacts of smoke inhalation (SI) and the therapeutic effects of oxygen microbubbles (OMB). Panel A shows a bar graph demonstrating a significant decrease in peripheral oxygen saturation (SpO2) from a baseline of ~98% to ~85% following smoke inhalation. Panel B presents ventral-dorsal and lateral thoracic x-rays of an animal model. The 'Control' images show clear lung fields and distinct cardiac silhouettes. In contrast, the 'Smoke Inhalation' images demonstrate diffuse, bilateral pulmonary infiltrates and increased lung opacity, characteristic of acute lung injury. Anatomical landmarks including the spine, ribs, and sternum are visible across both views. Panels C and D provide statistical dose-response analyses for SpO2 and partial pressure of arterial oxygen (PaO2). These graphs show that intraperitoneal administration of OMB, particularly at a dose of 10% body weight/volume (BW/V), significantly improves oxygenation compared to saline controls, indicating the potential for OMB to mitigate SI-induced hypoxemia.

This clinical graphic illustrates the real-time monitoring of Oxygen Reserve Index (ORI) and arterial oxygen saturation (SpO2) in a patient during the perioperative period. The chart displays two primary monitoring windows: (A) pre-oxygenation before tracheal intubation and (B) pre-oxygenation prior to extubation. The ORI (black line), a unit-less index ranging from 0.00 to 1.00, reflects oxygenation status in the moderate hyperoxic range (PaO2 ~100–200 mmHg). During initial pre-oxygenation (A), the ORI sharply rises to approximately 0.4 while SpO2 remains stable near 100%. Following intubation, the FiO2 is reduced to 35%, causing a significant drop in ORI to values fluctuating between 0.0 and 0.2, effectively avoiding hyperoxia. In phase (B), pre-oxygenation before extubation triggers a sharp spike in ORI toward its maximum value, indicating a robust oxygen reserve. This tool provides non-invasive clinical insight into oxygenation levels when SpO2 is already maximized and non-informative, allowing for safer airway management and precise titration of supplemental oxygen.

This Comparison Chart consists of a series of three anteroposterior (AP) chest radiographs (labeled A, B, and C) illustrating the radiological progression of a patient undergoing Extracorporeal Membrane Oxygenation (ECMO) for Acute Respiratory Distress Syndrome (ARDS). Radiograph (A), taken before ECMO initiation, shows severe, bilateral pulmonary congestion and diffuse, ill-defined opacities consistent with widespread alveolar edema or consolidation. Radiograph (B), taken during ECMO therapy, demonstrates a moderate reduction in pulmonary opacities and improved aeration of the lung fields. Radiograph (C), captured after ECMO weaning, reveals significant resolution of congestion with clearer lung parenchyma, indicating clinical improvement. Visible medical devices throughout the sequence include an endotracheal tube, multiple electrocardiogram (ECG) leads, and various vascular catheters (including potential ECMO cannulae and central venous lines). The series highlights the role of mechanical circulatory support in managing severe hypoxemia and pulmonary edema, providing a visual timeline of lung recruitment and recovery in a critical care setting.