Andrea Vercelli

Ketamine is a fast-acting N-methyl-D-aspartate (NMDA) receptor antagonist that can be used in a range of clinical scenarios in the pre-hospital setting and emergency department (ED). When compared with other anesthetic agents, ketamine has many unique properties, such as the ability to produce dose-dependent analgesic and anesthetic effects with a wide margin of safety. Ketamine may be used in the ED for sedation, pain management, and acute agitation treatment in the cases of benzodiazepine (BDZ)-resistant alcohol withdrawal syndrome (AWS) and substance use disorder. To highlight the efficacy and safety of ketamine, we reviewed the literature, starting with a description of four different cases of patients who presented to our ED and were treated with ketamine.

Methemoglobinemia (MET) is a life-threatening condition resulting from the development of methemoglobin (MetHb), which binds oxygen irreversibly, causing refractory hypoxia and so-called “functional anemia”. MET can be caused by hereditary or acquired processes. Acquired forms are the most common. Symptoms correlate with the MetHb level and range from cyanosis and dyspnea to dysrhythmias, metabolic acidosis, coma, and cardiac arrest. MetHb levels above 70% are fatal. Methylene blue (MB) is the specific antidote. In all cases, supportive treatment, including intravenous hydration, glucose correction, and oxygen supplementation, must be started immediately. Exchange transfusion has been used successfully to treat MET and may be appropriate in patients for whom MB is ineffective. We report the case of a 54-year-old woman who presented to our emergency department for the acute and sudden development of chest pain, shortness of breath, and severe cyanosis after drinking a significant amount of boiled courgette water. Arterial blood gas analysis revealed a MetHb level of 26%. She was treated immediately with MB, oxygen supplementation, and hydration with normalization of her MetHb in 12 hours. Our recommendation is to always investigate MET in patients with unexplained cyanosis and refractory hypoxia.

We report the case of a 52-year-old marathon runner admitted to our emergency department for exertional heat stroke (EHS). The electrocardiogram (ECG) showed a supraventricular tachycardia, probably an atrial flutter with 2:1 block, conducted with left bundle branch block. After 10 minutes of aggressive fluid management and rapid external cooling, the ECG returned to normal. As the high-sensitivity cardiac troponin I was elevated, coronary angiography and an electrophysiological study were performed, revealing normal coronary arteries and excluding inducible arrhythmias. As reported in the current literature, our findings confirm that the electrocardiographic changes and elevation of cardiac markers in EHS do not reflect cardiac ischemia, but rather a myocardial injury due to the pathophysiological response to dehydration and hyperthermia, which markedly impaired stroke volume and cardiac output. EHS is a life-threatening condition with a complex pathophysiology caused by thermoregulatory failure. Diagnosis is not always straightforward, but early recognition and timely management (the "golden hour") with rapid cooling and intravenous fluids are crucial to prevent irreversible and fatal organ damage. EHS is defined by a rectal temperature > 40.5 °C with symptoms or signs of neurological dysfunction, such as confusion, drowsiness, or seizures, which can rapidly worsen with delirium, coma, and cardiac arrest. With this case report, we want to remind emergency physicians that early diagnosis and appropriate management of EHS can avoid death and inappropriate treatment. (www.actabiomedica.it).

Dear Editor, In the recently published article by McLatchie et al., the authors state that emergency clinicians may miss acute aortic syndrome (AAS) by not considering it as a possibility, being falsely reassured by atypical or resolved symptoms, or mistaking it for other more common conditions.¹ The authors emphasise the importance of always considering AAS in the differential diagnosis of chest, back or abdominal pains, collapse, perfusion deficits or neurological compromise and suggest a risk stratification scoring system such as ADD-RS in combination with D-dimer to standardise the approach and help physicians discern which patients to scan.

Renal artery thrombosis is a severe and often misdiagnosed entity, that represents a true medical emergency in which renal infarction can occur. The diagnosis is often a challenge for the emergency physicians since it can mimic other more common diseases, including renal colic. We report the case of an 82-year-old man who presented to our emergency department for abdominal pain, nausea, and vomiting resulting from right renal artery thrombosis and infarction caused by misdiagnosed atrial fibrillation. Starting from our experience, we recommend to always keep renal thromboembolism in the differential diagnosis in a patient with sudden onset of flank/abdominal pain, high levels of lactate dehydrogenase and/or haematuria since early diagnosis and proper treatment are the keys to rapid recovery. (www.actabiomedica.it)

Wunderlich syndrome (WS) or spontaneous renal haemorrhage is a rare and life-threatening condition often leading to haemorrhagic shock. WS is characterized by an acute onset of non-traumatic subcapsular and perirenal haematoma formation due to several causes, including neoplasms, cystic rupture, vasculitis, coagulopathies, and infections. The classical presentation includes acute flank or abdominal pain, a palpable flank mass and hypovolemic shock (Lenk’s triad). Nausea, vomiting, fever, and haematuria can also be present. Computed tomography angiography is mandatory to localize the source of haemorrhage. Super-selective embolization can be performed to stop bleeding, while surgery is reserved to haemodynamic unstable patients and neoplastic cases. We describe a case of WS in a 79-year-old male patient, who rapidly developed hypovolemic shock requiring urgent nephrectomy. (www.actabiomedica.it)

Membranous nephropathy (MN) is the commonest cause of nephrotic syndrome (NS) in adult male patients worldwide. Most of the cases (80%) are idiopathic (primary MN, PMN), whereas about 20% are associated with autoimmune diseases, malignancies or exposures (secondary MN). PMN is a kidney-specific autoimmune glomerular disease mediated by antibodies to the M-type phospholipase A2 receptor (anti-PLA2R) (85%), thrombospondin type 1 domain containing 7A (THSD7A) (3-5%), or by other still unidentified mechanisms (10%). Most of the patients with PMN present with NS (80%). Clinical course of PMN is characterised by spontaneous remissions (40%) and relapses (15-30%). One third develop end-stage renal disease (ESRD) within 5 to 15 years from the onset. Anti-PLA2R/THSD7A antibodies levels correlate with proteinuria, clinical course, and outcomes. The treatment still remains matter of debate. Hypertension, proteinuria, and hyperlipidaemia must be treated in all patients. Immunosuppressive therapy is indicated in patients with elevated anti-PLA2R/THSD7A levels and proteinuria >3.5 g/d at diagnosis. With proper management, only 10% or less will develop ESRD over the subsequent 10 years. Here we report a case of a 34-year-old male patient with a ten-year history of asymptomatic PMN, treated with ACE-inhibitors, who presented to our emergency room for acute chest pain and exertional dyspnoea due to ESRD that required urgent dialysis. (www.actabiomedica.it).

Introduction: The early identification of patients with SARS-CoV-2 infection is still a real challenge for emergency departments (ED). First, we aimed to develop a score, based on the use of the lung ultrasonography (LUS), in addition to the pre-triage interview, to correctly address patients; second, we aimed to prove the usefulness of a three-path organization (COVID-19, not-COVID-19 and intermediate) compared to a two-path organization (COVID-19, non-COVID-19). Methods: We retrospectively analysed 292 patients admitted to our ED from 10 April to 15 April 2020, with a definite diagnosis of positivity (93 COVID-19 patients) or negativity (179 not-COVID-19 patients) for SARS-COV-2 infection. Using a logistic regression, we found a set of predictors for infection selected from the pre-triage interview items and the LUS findings, which contribute with a different weight to the final score. Then, we compared the organization of two different pathways. Results: The most informative factors for classifying the patient are known nasopharyngeal swab positivity, close contact with a COVID-19 patient, fever associated with respiratory symptoms, respiratory failure, anosmia or dysgeusia, and the ultrasound criteria of diffuse alveolar interstitial syndrome, absence of B-lines and presence of pleural effusion. Their sensitivity, specificity, accuracy, and AUC-ROC are, respectively, 0.83, 0.81, 0.82 and 0.81. The most significant difference between the two pathways is the percentage of not-COVID-19 patients assigned to the COVID-19 area, that is, 10.6% (19/179) in the three-path organization, and 18.9% (34/179) in the two-path organization (p = 0.037). Conclusions: Our study suggests the possibility to use a score based on the pre-triage interview and the LUS findings to correctly manage the patients admitted to the ED, and the importance of an intermediate area to limit the spread of SARS-CoV-2 in the ED and, as a consequence, in the hospital.

Kounis syndrome (KS) is a coronary syndrome in the setting of allergic/anaphylactic reactions and can be classified in three variants: vasospastic allergic angina (type I), allergic myocardial infarction (type II) and stent thrombosis (type III). The early diagnosis is of paramount importance for the correct management and the prognosis, being KS a life-threatening emergency condition. KS is not uncommon, but it is frequently unrecognized or undiagnosed in virtue of its broad clinical manifestations. The diagnosis should be based on the combination of cardiovascular and allergic/anaphylactic clinical symptoms and signs, as well as on laboratory, electrocardiographic, echocardiographic, and angiographic evidence. ECG monitoring, cardiac enzymes and troponin are mandatory to confirm or exclude KS in a patient with subclinical or clinical, acute or chronic allergic reactions. Nevertheless, the treatment is a real challenge for the emergency clinicians because guidelines have not been established yet, and the therapy is based on the variant type. We herein report the case of type I KS in a woman with no prior history of allergy, admitted to our emergency department for abdominal pain, nausea and hematochezia. Starting from this case we conducted a systematic search of the following databases: PubMed, Google Scholar, Science Direct, Medline, using the keywords of "Kounis syndrome", "coronary spams", "cardiac arrest", "sudden death", "allergy", and "anaphylaxis". The main purpose of this review is to remind emergency clinicians to keep a high index of suspicion regarding KS when dealing with patients with allergic reactions or anaphylaxis to promptly identify and correctly manage KS.

In the so called COVID19 era, headache, fever and gastrointestinal symptoms are highly suggestive for SARS-CoV-2 infection, but in all the cases presenting to the emergency room, clinicians should always keep in mind alternative diagnoses, particularly if the patient is pregnant. Life-threatening diseases, such as eclampsia and posterior reversible encephalopathy syndrome (PRES), should be promptly recognized and treated. Eclampsia is defined as a seizure occurring in association with pre-eclampsia, and it represents one of the major and serious obstetric disorders associated with significant maternal and perinatal morbidity and mortality. PRES is a distinctive clinical and imaging syndrome characterized by acute headaches, visual impairment, seizures, and altered sensorium, that can be associated with severe eclampsia. Emergency clinicians should always consider eclampsia in the differential diagnosis of headache in pregnant women. The prompt and accurate diagnosis of eclampsia/PRES is crucial to prevent adverse maternal and perinatal outcomes. Here we describe the case of a young pregnant woman admitted to our emergency department for fever, dyspnea, headache, nausea and vomiting, who developed generalized tonic clonic seizures and a subsequent status epilepticus due to eclampsia and PRES. (www.actabiomedica.it)