DDX by Vital Signs

Hyperthermia/Fever 

Infection 

Malignancy 

Inflammatory/rheumatologic 

Hyperthyroidism 

PE 

Drugs 

NMS (antipsychotics) 

MH fron anaesthetic, heat stress 

Serotonin syndrome 

Hypothermoia 

environmental exposure 

Hypothyroidism 

adrenal insufficiency 

Sepsis 

neuromuscular disease 

Malnutrition 

thiamine deficiency 

hypoglycemia.  

Ethanol abuse and carbon monoxide intoxication in some cases 

Meds: MC medications that impair thermoregulation are anxiolytics, antidepressants, antipsychotics, and opioids.  

Meds: that can impair a patient's ability to compensate for low temp = po antihyperglycemics, BBs, alpha agonists (eg, clonidine), and general anesthetic agents 

Tachypnea  

Metabolic acidosis from (DKA vs OH/starvation ketoacidosis vs ASA/methanol/ethylene glycol poisoning vs CKD) 

Hyperthyroidism  

Pregnancy 

Pheochromocytoma 

Hypoglycemia 

Hypocalcemia 

Cardiac: ACS, HF, PE 

Pulmonary: PTX, Airway dz (copdae, asthma, upper airairway obstruction,etc) 

Infection/sepsis 

CNS disorder: s/p grand mal seizure, brainstem pathology, central hyperventilation syndrome. 

Tachycardia – PHAT HADES 

P pain 

H hypovolemia 

A anxiety 

T fever 

H hypoxia 

A anemia 

D drugs 

E etoh withdrawal(esp if at rest), opiate withdrawal 

S systemic prob pheochromocytoma, thyroid 

Other 

- Too much fluid can cause atrial stretch= tachycardia. 

Bradycardia 

Sinus Bradycardia 

Sinoatrio block 

AV block( I, II, III) 

ICH 

Hypothermia 

Hyperkalemia 

Hypoxia 

AMI 

OSA

Long QT syndrome 

Meds: antiarrhythmics, BBs, antHTNs(clonidine methyldopa), lithium, amitriptyline, Precedex. 

Autonomic: vasovagal, carotid sinus hypersensitivity 

Hypothyroidism 

Athlete/baseline 

Anorexia 

Infection(sepsis, lyme disease) 

Spinal cord injury 

Hypotension 

Hypovolemic(collapsed IVC, hyperdynamic heart, no b-lines) 

• Dehydration 

• GI bleed/RP bleed 

• Trauma 

• Poor PO intake 

• Gastroenteritis 

Cardiogenic(dilated IVC, hypodynamic heart, b lines) 

• MI 

• HF exacerbation 

• Myocarditis 

• Toxin/drugs including BBs 

• Valve insufficiency 

• Arrythmias(a-fib, secondary afib(volume down), abnormal electrolytes) 

Distributive(collapsed ivc, hyperdynamic heart, no b lines) 

• Sepsis 

• Anaphylaxis 

• Drugs/Toxins 

• Neurogenic: spinal cord injury, brain injury, neurogenic stress cardiomyopathy

Obstructive(dilated ivc, hyperdynamic heart, no b lines) 

• PE 

• Tamponade 

• Pneumothorax 

• IPH 

Undifferentiated: 

• Toxic/Drug induced: CCB, BB, Clonidine, digoxin, opiates, sedatives, VPA, TCA, Phenothiazine, CO 

• Occult: Acidosis(get ABG, BMP, consider bicarb or RRT), hyper/hypothyroid(get TSH/t4, consider empiric tx), anaphylaxis, adrenal issue(consider hydrocort), hypocalcemia, occult GI bleed, RP bleed, Toxin(BB/CCB toxicity), 2nd cause of shock, Orthostatic hypotension, vasovagal hypotension. 

Hypertension(urgency/emergency) 

Essential untreated 

Discontinued meds/noncompliance 

Neurologic emergencies: Ischemic/hemorrhagic stroke, head trauma, hypertensive encephalopathy 

MC Cardiac emergencies: acute LV dysfunction with pulmonary edema, ACS, Acute HF,  

Vascular emergencies: acute aortic dissection, recent vascular surgery rebleed?, epidural hematoma 

Renal emergencies: acute hypertensive nephrosclerosis 

Ingestion of sympathomimetic agents (eg, tyramine-containing foods in patients who take chronic monoamine oxidase inhibitors [11], amphetamine-like compounds, cocaine, etc)  

Pheochromocytoma  

Severe autonomic dysfunction (eg, Guillain-Barré and multiple system atrophy syndromes or acute spinal cord injury)