Inadvertent arterial puncture involving the subclavian artery and the aorta during central venous catheterization: a case report.

BACKGROUND: This case report describes a subclavian vein cannulation that inadvertently led to an arterial puncture with the catheter tip radiologically seen at the level of the aorta. This case emphasizes the importance of postprocedural imaging and the disadvantages of not using ultrasound guidance in central venous catheterization. CASE PRESENTATION: A 24-year-old Caucasian man with diabetes mellitus type 1 presented himself to the emergency department due to abdominal pain accompanied by nausea and vomiting. The patient's vital signs revealed blood pressure of 84/53 mmHg, heart rate of 103 beats per minute, respiratory rate of 18 breaths per minute, and temperature of 98.2 °F (36.7 °C). On physical examination, he was found to have dry oral mucosa with poor skin turgor, with diagnostics showing that he was in diabetic ketoacidosis after running out of insulin for 2 days. The patient was transferred to the intensive care unit to receive a higher level of care. Unfortunately, due to difficulty of peripheral line placement, only a gauge-22 cannula was secured at the left dorsum of the hand. Efforts to replace the current peripheral line were unsuccessful, and a decision to perform a central vein cannulation via the internal jugular vein was made. This was futile as well due to volume depletion, prompting a subsequent right subclavian vein route attempt. The procedure inadvertently punctured the arterial circulation, leading to the catheter tip being visible at the level of the aorta on postprocedure X-ray. The subclavian line was immediately removed with no adverse consequences for the patient. A right femoral line was successfully placed, and continuous management of the diabetic ketoacidosis ensued until normalization of the high anion gap was achieved. CONCLUSION: Utilization of real-time ultrasound guidance via the subclavian approach could have allowed for direct visualization of needle insertion to the anatomical structures, guidewire location, and directionality, all of which can lead to decreased complications and improved cannulation success compared with the landmark technique. A leftward direction of the catheter seen on postprocedural X-rays should raise high suspicion of inadvertent catheter placement and immediate correction. This complication should have been prevented if ultrasound guidance had been used.

Synthetic cannabinoid induced acute respiratory depression: Case series and literature review.

Synthetic Cannabinoids are a street drug that is widely attainable and cheap compared to natural cannabis, and has variable potency and unpredictable effects with no commercially available diagnostic test to confirm its presence. Similar to natural cannabis, Synthetic Cannabinoid intoxication can present in several ways with the most common emergency room presentations to be of neurologic and psychiatric manifestation. The respiratory depressive effect of Synthetic Cannabinoids has not been well documented in medical literature. We report four patients admitted in the Intensive Care Unit with acute respiratory failure necessitating endotracheal intubation after use of Synthetic Cannabinoid. All patients had a reversal of respiratory failure in less than 24 h, three patients had a complicated course due to aspiration pneumonia. All four patients exhibited aggressive behavior, with two of them diagnosed with Bipolar Disorder and Cocaine Use Disorder. The effect of Synthetic Cannabinoids in peripheral receptors such as chemoreceptors and baroreceptors can increase bronchial airway resistance. It is postulated that CB1 receptor stimulation could be one of the possible mechanisms of synthetic cannabinoid-induced respiratory depression. Chemical gases released after its inhalation may also cause damage to the bronchiolar epithelium and has the potential to disrupt the protective surfactant layer in the alveoli, which then could interfere with effective gas exchange leading to hypoxia and acidosis. The stimulation of CB1 receptors have a series of downstream signaling effects in the G protein-coupled pathway and mitogen-activated protein kinase (MAPK) pathway, causing suppression of both excitatory and inhibitory neuronal activity. The aforementioned molecular changes in the central nervous system after CB1 receptor stimulation could impact respiration. The use of Synthetic Cannabinoids can cause respiratory depression in individuals without an underlying pulmonary disease and adds to the growing number of literature about the presentation and debilitating adverse events from its consumption. Although there is no specific toxidrome associated with it, clinicians should have a high index of suspicion with its use especially in patients presenting with a history of drug overdose.