Editing Reduction of Risk Potential (section)

== Vital Signs: Abnormalities and Their Causes ==

Reference values for a resting adult: temperature roughly 36.5 to 37.5 degrees Celsius (97.7 to 99.5 degrees Fahrenheit) orally, heart rate 60 to 100 beats per minute, respiratory rate 12 to 20 breaths per minute, blood pressure below 120/80 mm Hg as the normal category, and peripheral oxygen saturation 95 to 100 percent. Pediatric heart and respiratory rates are considerably higher and decline with age; older adults may have a blunted febrile response, so a temperature of 37.8 degrees Celsius in an older adult can represent significant infection (Potter et al., 2023).

;Tachycardia
Pain, anxiety, fever, hypovolemia and hemorrhage, hypoxia, anemia, dehydration, shock, hyperthyroidism, heart failure, sepsis, alcohol or drug withdrawal, and medications including beta agonists and anticholinergics. In bleeding, tachycardia typically appears '''before''' hypotension, which makes it the more useful early warning (Ignatavicius et al., 2021; Potter et al., 2023).

;Bradycardia
Beta blockers, calcium channel blockers, digoxin, increased intracranial pressure, hypothyroidism, hypothermia, vagal stimulation from suctioning, straining, or vomiting, conduction block, and athletic conditioning as a benign cause (Potter et al., 2023).

;Tachypnea
Hypoxia, fever, pain, anxiety, metabolic acidosis, pulmonary embolism, pneumonia, and heart failure (Potter et al., 2023).

;Bradypnea
Opioid and sedative effect, increased intracranial pressure, and neuromuscular disease. Nursing application: a respiratory rate below 12 in a client receiving opioids, especially with increasing sedation, calls for stopping further opioid dosing, stimulating the client, applying oxygen, and reporting; naloxone is reserved for significant respiratory depression because it reverses analgesia and can precipitate severe pain and withdrawal (Harding et al., 2023).

;Hypotension
Hypovolemia, hemorrhage, sepsis, cardiogenic causes, anaphylaxis, neurogenic causes such as spinal cord injury, adrenal insufficiency, and antihypertensive, opioid, or anesthetic effect. Orthostatic hypotension is commonly defined as a drop of at least 20 mm Hg systolic or 10 mm Hg diastolic within three minutes of standing, and it is a major fall risk (Potter et al., 2023).

;Hypertension
Pain, anxiety, essential hypertension, fluid overload, renal disease, increased intracranial pressure, pre-eclampsia, thyroid storm, and stimulant use. A narrowing pulse pressure occurs with hypovolemia and cardiac tamponade. A '''widening''' pulse pressure with bradycardia and irregular respirations is Cushing triad, a late and ominous sign of increased intracranial pressure (Ignatavicius et al., 2021).

;Fever
Infection, inflammation, dehydration, transfusion reaction, drug reaction, malignant hyperthermia, and neuroleptic malignant syndrome. A temperature rise within the first 24 to 48 hours after surgery is frequently atelectasis, which is why early mobility, incentive spirometry, and deep breathing are emphasized. Later postoperative fever suggests wound infection, urinary tract infection, pneumonia, or venous thromboembolism (Ignatavicius et al., 2021; Potter et al., 2023).

;Falling oxygen saturation
Verify the waveform and probe placement first, since poor perfusion, cold extremities, motion, nail polish, and severe anemia distort readings. Pulse oximetry does not detect carbon monoxide poisoning or hypercapnia (Potter et al., 2023).