the leakage of a fluid out of its container. In the case of inflammation, it refers to the movement of white blood cells from the capillaries to the tissues surrounding them (diapedesis). In the case of malignant cancer metastasis it refers to cancer cells exiting the capillaries and entering organs. It is frequently used in medical contexts, either referring tourine, or to blood.
Suction: Hemovac & Jackson Pratt
Jackson Pratt (JP, "grenade") drains help remove fluids from surgical area. This helps your surgical site heal.
Empty drainage fluid into a measuring cup and record amount of fluid. While maintaining pressure, replace plug. Slowly release your grip to re-establish suction.
A hemovac is a round drain with springs inside that must be compressed to establish proper suction. To re-establish suction, squeeze the drain on both sides until the drain appears to be flat. While maintaining suction, replace the plug and release your grip.
PCA by proxy
term means that PCA pump is activated by someone other than patient, commonly family or friends. This practice overrides an important safeguard built into PCA: A patient who is already sedate won't push the button and give himself unnecessary and excessive medication.(oversedation)
Teach patient and family about safe PCA use and explain why no one but the patient should ever push the button for medication. Place warning signs on all PCA pumps that say "For patient use only." Patient family and friends should be under close observation.
Maybe appropriate in some settings e.g. pediatrics where patient unable to push button.
- Using a sedation-rating tool consistently and frequently is the key to preventing oversedation and other potential problems.
- S 5 Sleep, easy to arouse
- Acceptable; no action necessary; may increase opioid dose if needed
- 1. Awake and alert
- Acceptable; no action necessary; may increase opioid dose if needed
- 2. Slightly drowsy, easily aroused
- Acceptable; no action necessary; may increase opioid dose if needed
- 3. Frequently drowsy, arousable, drifts off to sleep during conversation
- Unacceptable; monitor respiratory status and sedation level closely until sedation level is stable at less than 3 and respiratorystatus is satisfactory; decrease opioid dose 25% to 50%1 or notify prescriber2 or anesthesiologist for orders; consideradministering a non-sedating, opioid-sparing nonopioid, such as acetaminophen or an NSAID, if not contraindicated.
- 4. Somnolent, minimal or no response to verbal or physical stimulation
- Unacceptable; stop opioid; consider administering naloxone; notify prescriber or anesthesiologist; monitor respiratory statusand sedation level closely until sedation level is stable at less than 3 and respiratory status is satisfactory.
is transient, moderate to severe pain that occurs beyond pain treated by current analgesics e.g. some cancer pain; usually rapid onset and brief duration
gold standard is morphine sulfate
refers to the dose of one analgesic that is equivalent in pain-relieving effects compared with another analgesic
permits substitition in case of ineffective or intolerable side effects.
Narcan (naloxone hydrochloride) is a narcotic antagonist. It works by blocking opiate receptor sites, which reverses or prevents toxic effects of narcotic (opioid) analgesics.
Completely or partially reversing the effects of narcotics. It may also be used to diagnose overdose of narcotics.
Fentanyl (also known as fentanil, brand names Sublimaze, Actiq, Durogesic, Duragesic, Fentora, Onsolis, Instanyl, Abstral, and others) is a potent synthetic narcotic analgesic with a rapid onset and short duration of action. It is a strong agonist at the μ-opioidreceptors. Historically it has been used to treat chronic breakthrough pain and is commonly used in pre-procedures as a pain reliever as well as an anesthetic in combination with a benzodiazepine.
Fentanyl is approximately 100 times more potent than morphine
acetaminophen and hydrocodone
Norco tablets contain a combination of acetaminophen and hydrocodone. Hydrocodone belong to a group of drugs called narcotic pain relievers.Acetaminophen is a less potent pain reliever that increases the effects of hydrocodone.Norco is used to relieve moderate to severe pain.
Toradol is in a group of drugs called nonsteroidal anti-inflammatory drugs (NSAIDs). It works by reducing hormones that cause inflammation and pain in the body.Toradol is used short-term (5 days or less) to treat moderate to severe pain, usually after surgery. It is used alone or in combination with other medicines.
acetaminophen and oxycodone
Percocet contains a combination of oxycodone and acetaminophen. Oxycodone is in a group of drugs called narcotic pain relievers.Acetaminophen is a less potent pain reliever that increases the effects of oxycodone.Percocet is used to relieve moderate to severe pain.
acetaminophen and hydrocodone
Vicodin is a tablet containing a combination of acetaminophen and hydrocodone. Hydrocodone is in a group of drugs called narcotic pain relievers.Acetaminophen is a less potent pain reliever that increases the effects of hydrocodone.Vicodin is used to relieve moderate to severe pain.
Obstruction of the intestine due to paralysis of the intestinal muscles. The paralysis does not need to be complete to cause ileus, but the intestinal muscles must be so inactive that it prevents the passage of food and leads to a functional blockage of the intestine. Ileus commonly follows some types of surgery, especially abdominal surgery. It also can result from certain drugs, spinal injuries, inflammation anywhere within the abdomen that touches the intestines, and diseases of the intestinal muscles themselves. Irrespective of the cause, ileus causes constipation, abdominal distention, and nausea and vomiting. On listening to the abdomen with a stethoscope, few or no bowel sounds are heard (because the bowel is inactive).
is the premature "bursting" open of a wound along surgical suture. It is a surgical complication that results from poor wound healing. Risk factors are age, diabetes, obesity, poor knotting or grabbing of stitches, and trauma to the wound after surgery. Sometimes a pink (serosanguinous) fluid may leak out. A possible cause of wound dehiscence includes inadequate scar formation.
Evisceration is a rare but severe surgical complication where the surgical incision opens (dehiscence) and the abdominal organs then protrude or come out of the incision (evisceration). Evisceration is an emergency and should be treated as such.
cover the opening and organs with the cleanest sheet or bandage material you have, after wetting it thoroughly. If you have been bandaging your wound, you should have the supplies to cover the tissue with sterile bandages. The fabric/bandage needs to be moist, to prevent it from adhering to tissue. If you have sterile saline, use it to saturate the bandage or towel.
keep the patient calm and seated or lying down
is a surgical device placed in a wound to drain fluid. It consists of a soft rubber tube placed in a wound area, to prevent the build up of fluid.
A Penrose drain removes fluid from a wound area. Frequently it is put in place by a surgeon after a procedure is complete to prevent the area from accumulating fluid, such as blood, which could serve as a medium for bacteria to grow in.
Nonpharmacologic pain therapy
Reduce dose of analgesic required and minimize side effects; possibly alter ascending nociceptive input or stimulate descending pain modulation mechanisms
- TENS or PENS
- Heat or cold therapy
- Cognitive therapies: Distraction, Hypnosis, Imagery, Relaxation
Opioids Side Effects
- CNS depression: Leads to respiratory depression; most serious adverse effect
- Nausea and vomiting
- Urinary retention
- Diaphoresis and flushing
- Pupil constriction (miosis)
- Constipation: a common adverse effect and may be prevented with adequate fluid and fiber intake
- Opioid Tolerance: A common physiologic result
- of chronic opioid treatment. Result: larger dose is
- required to maintain the same level of analgesia
: Physiologic adaptation of the body to the presence of an opioid.
Opioid tolerance and physical dependence are expected with long-term opioid treatment and should not be confused with psychologic dependence (addiction)
Weaning off opiates
Regardless of withdrawal symptoms, when a patient experiences severe respiratory depression, an opioid antagonist (naloxene [Narcan]) should be given.
Physical dependence is seen when the opioid is abruptly discontinued or when an opioid antagonist is administered
weaning from opioids can be done safely byslowly tapering the opioid dose
A decrease by 10% of the original dose per week is usually well tolerated with minimal physiological adverse effects. Some patients can be tapered more rapidly without problems (over 6 to 8 weeks).
Symptoms of mild opioid withdrawal may persist for six months afteropioids have been discontinued.
Consider using adjuvant agents, such as antidepressants to manageirritability, sleep disturbance or antiepileptics for neuropathic pain.
Do not treat withdrawal symptoms with opioids or benzodiazepines afterdiscontinuing opioids.
Scale 0 - 10
Pain scale are usuful tools to help patient communicate pain intensity. Numeric scales, verbal descriptor scales (e.g. more, little, moderate, severe) or visual analog scale (e.g. line with one end "no pain" and other end labeled with "worst possible"; patient points to line)
- Mild 1-3
- non-opioids, ASA, acetaminophen, NSAIDs
- Moderate 4-6
- opoiods: codeine, oxycodone (Percodan), propoxyphen (Darvon)
- Severe 7-10
- opioids: morphine, hydromorphone, meperidine (Demerol - avoid) Fentanyl
- RBG (random blood glucose) > 200 mg/dL + symptoms (polydipsia, polyphagia, polyuria and weight loss)
- FBG (fasting blood glucose) > 126 mg/dL
- OGTT (75g) 2hr glucose > 200 mg/dL
- Normal blood glucose 70-100 mg/dL
- IFG (impaired fasting glucose) 100 - 126 mg/dL
- IGT (impaired glucose tolerance) 140 - 199 mg/dL
- Type I:
- - body's own T cells ttack and destroy pancreatic beta cells
- - typicallty seen in people with lean body type
- long preclinical period; may be present for years before onset of symptoms
- - onset of symptoms rapid once start
- - classic symptoms: polydipsia, polyphagia, polyuria and unexplained weight loss
- - requires supply of exogenous insulin
- - consistency in timing and food eaten important
- Type II
- - insufficient insulin production and/or poor utilization by tissues
- - 90% of patients with diabetes
- - greater prevalence in some ethnic populations: African Americans, Native Americans, Asian Americans, and Hispanic Americans
- - calorie and fat reduction is goal in nutritional therapy
- - weight loss of 5% - 7% improves glycemic control
- - weight loss via moderate decrease in calories (500cal/day) and increase in caloric expenditure
high and dry
- dry skin
- recurrent blurred vision
- weight loss
- - administer IV fluids to correct dehydration
- - administer insulin therapy (bolus then IV infusion) to reduce blood glucose and serum acetone
- - administer electrolytes to correct electrolyte imbalance
- - assess renal status (urine output)
- - monitor level of consciousness
- - assess vital signs to determine presence of fever, hypovolemic shock, tachycardiaand Kussmaul respirations
blood glucose < 70 mg/dL
incorrect insulin (over) dose
- skipped meal
- alcohol consumption
- increased physical exercise
- drug interaction
- Extreme hunger
- 15:15 - provide 15g of carbohydates (not candy/chocolate bars which has fat which slows absorption) then check in 15 minutes, such as 4-6oz of fruit juice or regular soft drink or 8oz of low fat milk.
once symptoms improved, eat longer-lasting carbohydrate such as bread or milk
administer glucagon if unconscious or ineffective oral treatment; or 50ml 50% IV glucose
Insulin administration sites
- subcutaneous injection; do not aspirate
- always take blood glucose reading before administering insulin
speed of absorption (fast to slow): abdomen > arm > thigh > buttock
do not inject into site to be exercised (variable/faster absorption and onset/peal of action)
rotate injections within one particular site to avoid variable absorption; half-inch square
associated with occurrence of undetected hypoglycemia during sleep; patient c/o headache on awakening, night sweats or nightmares, and patient's blood glucose is elevated on awakening in morning
early AM (hypoglycemia) >> morning (hyperglycemia) >> increase insulin
: LESS insulin
- - Rebound effect in which an overdose of insulin causes hypoglycemia
- - Usually during hours of sleep
- - Counterregulatory hormones released; Rebound
- hyperglycemia and ketosis occur
Insulin syringe and pens
- routine handwashing with soap and water sufficient; if in hospiral, alcohol swab to prevent nosocomial infections.
- need corresponding syringe with insulin concentration e.g. U100 insulin with U100 insulin syringe
- Insulin Pens
- 1. prepare for injection
- - check label to make sure using correct insulin
- 2. attach new needle
- 3. preform safety test
- - select dose of 2 units
- - hold pen with needle pointing upward; tap reservoir gently so any air bubbles rise to needle
- - press injection button; check that insulin does come out
- - removes air bubbles and ensures that pen and needle are working properly
- 4. select required dose
- 5. inject dose
- - press injection button in all the way. hold button for 10 seconds then withdraw needle
- 6. remove needle
Mealtime insulin (bolus) / Supplemental Insulin
for control of postmeal blood glucose levels
rapid-acting synthetic insulin analogs have an onset of approximately 15 minutes and should be injected 0-15 minutes before meal; includes lispro (Humalog), aspart (Novolog), and glusiline (Apidra)
short-acting regular insulin has an onset of 30-60 minites and should be injected 30-45 minutes before meal; includes regular insuin (Humulin R, Novolin R)
long-acting / background insulin
for people who must long-acting basal (background) insulin to control blood glucose in between meals and overnight; without, increased risk of DKA
- include glargine (Lantus) [DO NOT MIX] and detemir (Levemir)
- used once daily at bedtime or morning (consistent time each day)
: NPH 1-4hr onset; 4-12hour peak; 14-24hour duration
risk for hypoglycemia is reduced
Glycosated hemoglobin A1C
to help determine glycemic levels over time; not used as diagnostic test for diabetes
shows amount of glucose attached to hemoglobin molecules over their life span; amount of glucose attached to hemoglobin increases when blood glucose increases over time
indicates overall glucose control for previous 90-120 days
ideal is 7% or less for people with diabetes
can be affected by diseases affecting RBCs e.g. sickle cell anemia
Foot Care (diabetic)
- - inspect feet daily, especially area between toes
- - wash feet daily with lukewarm water and soap; dry thoroughly
- - do no apply moisturizing cream to area between toes
- - change into clean cotton socks every day
- - check shoes for foreign objects (nails, pebbles) before putting them on
- - buy shoes later in the day when feet are normally larger; have plenty of room for your toes
- - trim nails straight across with nail clipper
- - do nottreat blisters, sores or infections with home remedies
- - check temperature of water with wrist before stepping into bathtub
- - do not use very hot or cold water. Never use hot water bottles, heating pads, or portable heaters to warm feet
- - do not go barefoot
- - do not soak you feet
- - do not cross legs or wear garters or tight stockings that constrict blood flow
Sick Day instructions
- 1. contact MD if pain, fever, diarrhea, difficulty breathing, moderate or large ketones, blood sugar > 250-300 mg/dL, unresponsive to insulin, mental status changes vomiting or cannot hold down food.
- 2. always take usual does of insulin or oral diabetes medication. Never omit medication even if unable to eat.
- 3. Test blood sugar Q3-4hours or minimum of 4X per day. Test blood glucose levels at least before each meal (ac) and at bedtime (hs).
- 4. Check urine if blood sugar over 240mg/dl (especially if Type I)
- 5. Drink 9 ounces of caffeine-free and alcohol-free liquid every hour, such as water, caffeine-free tea, consomme, fruit juices, and regular or diet sodas. Take at 15 grams of carbohydrates every 1-2 hours.
- 6. Consult with MD before taking OTC meds and other prescriptions.
- 7. Rest and do not exercise.
- - avoid heating and freezing which alters insulin molecules
- - current insulin vials may be left at room temperature for up to 4 weeks; extra insulin stored in refrigerator
- - avoid prolonged exposure to direct sunlight
- - store insulin in thermos or cooler to keep cool if traveling in hot cimates
- - prefilled syringes are stable for up to 30 days when stored in refrigerator; store syringes prefilled with cloudy solution with needle pointing up
- - roll prefilled syringes between palms before injection to warm refrigerated insulin and to resuspend particles
Oral diabetic agents
Work to improve mechanisms by which insulin and glucose are produced and used by the body
- Work on three defects of type 2 diabetes
- - Insulin resistance
- - Decreased insulin production
- - Increased hepatic glucose production
- ↑ Insulin production from pancreas
- examples: Glipizide (Glucotrol), Glimepiride (Amaryl)
- Increase insulin production from pancreas
- Taken 30 minutes before each meal up to time of meal
- Should not be taken if meal skipped
- examples: Repaglinide (Prandin), Nateglinide (Starlix)
- Reduce glucose production by liver
- Enhance insulin sensitivity at tissues
- Improve glucose transport into cells
- Do not promote weight gain
- example: Metformin (Glucophage)
- α-Glucosidase inhibitors
- “Starch blockers” slow down absorption of carbohydrate in small intestine
- example: Acarbose (Precose)
- Most effective in those with insulin resistance
- Improves insulin sensitivity, transport, and utilization at target tissues
- examples: Pioglitazone (Actos), Rosiglitazone (Avandia)
- Amylin analog
- Hormone secreted by beta cells of pancreas
- Cosecreted with insulin
- Indicated for type 1 and type 2 diabetics
- Slows gastric empyting, reduces postprandial glucagon secretion, increases satiety
- example: Pramlintide (Symlin)
- Incretin mimetic
- Synthetic peptide
- Stimulates release of insulin from b cells
- Subcutaneous injection
- Suppresses glucagon secretion
- Reduces food intake
- Slows gastric emptying
- Not to be used with insulin
- example: Byetta
person with diabetes can eat same foods as person who does not have diabetes
Nutritional energy intake should be balanced with energy output
- Carbohydrates and monounsaturated fats should provide 45% to 65% of total energy intake
- Fats no more than 25% to 30% of meal plan’s total calories; <7% fromsaturated fats
- Protein contribute <10% of total energy consumed
- Intake should be significantly less than general population
- - High in calories
- - No nutritive value
- - Promotes hypertriglyceridemia
- - Detrimental effects on liver
- - Can cause severe hypoglycemia
- Type 1 diabetes mellitus
- - Meal plan based on individual’s usual food intake and is balanced with insulin and exercise patterns
- - Insulin regimen managed day to day
- Type 2 diabetes mellitus
- - Emphasis based on achieving glucose, lipid, and blood pressure goals
- - Calorie reduction
Exercise and diabetes
- - Monitor blood glucose levels before, during, and after exercise
- - Essential part of diabetes management
- - ↑ Insulin receptor sites
- - Lowers blood glucose levels
- - Contributes to weight loss
- - Several small carbohydrate snacks (10-15g CHO) can be taken every 30 minutes during exercise to prevent hypoglycemia
- - Best done after meals; 1hr after meals
- - Exercise plans should be started after medical
- - ok if blood glucose > 100 mg/dl and < 250 mg/dl
Self-monitoring of Blood Glucose
- 1. wash hands with soap and water; alcohol for site not needed unless in hospital. Dry finger before puncturing.
- 2. If difficult to obtain adequate drop of blood for testing,warm hands in warm water or let arms hang dependently for few minutes before finger puncture.
- 3.Use side of finger pad rather than near center since fewer nerve endings are along side of finger pad.
- 4. Puncture should only be deep enough to obtain large drop of blood. Unnecessarily deep punctures may cause pain and bruising
Foot ulcers (diabetic)
- - Most common cause of hospitalization in diabetes
- - Result from combination of microvascular and macrovascular diseases
- - Risk factors: Sensory neuropathy, Peripheral
- arterial disease,
- - Other contributors: Smoking, Clotting abnormalities,
- Impaired immune function, autonomic neuropathy
- - Loss of Protective Sensation (LOPS) often prevents patient from becoming aware that (foot) injury has occurred
Ankle Brachial Index (ABI)
the ratio of the blood pressure in the lower legs to the blood pressure in the arms. Compared to the arm, lower blood pressure in the leg is an indication of blocked arteries (peripheral vascular disease). The ABI is calculated by dividing the systolic blood pressure at the ankle by the systolic blood pressures in the arm.
ABI values < 0.9 & >1.3 should be investigated
A Doppler ultrasound blood flow detector, commonly called Doppler Wand or Doppler probe, and a sphygmomanometer (blood pressure cuff) are usually needed. The blood pressure cuff is inflated proximal to the artery in question. Measured by the Doppler wand, the inflation continues until the pulse in the artery ceases. The blood pressure cuff is then slowly deflated. When the artery's pulse is re-detected through the Doppler probe the pressure in the cuff at that moment indicates the systolic pressure of that artery.
Intermittent Claudication (diabetic)
clinical diagnosis given for muscle pain (ache, cramp, numbness or sense of fatigue), classically in the calf muscle, which occurs during exercise and is relieved by a short period of rest. It disappears after a brief rest and the patient can start walking again until the pain recurs.
- All the "P's"
- Increase in Pallor
- Decrease in Pulses
Exercise can improve symptoms; increased blood flow enhances the creation of collateral vessels to the affected muscle. Catheter based intervention is also an option. Atherectomy, stenting, and angioplasty to remove or push aside the arterial blockages are the most common procedures via catheter based intervention. These procedures can be performed by interventional radiologists, interventional cardiologists, vascular surgeons and thoracic surgeons, among others.Surgery is the last resort; vascular surgeons can perform either endarterectomies on arterial blockages or perform an arterial bypass.
- Diabetics more susceptible to infections
- Defect in mobilization of inflammatory cells
- Impairment of phagocytosis by neutrophils and monocytes
Hypovolemic Shock - Assessment
occurs when there is aloss of intravascular fluid; volume is inadequate to fill the vascular space
results when the fluid is lost through hemorrhage, GI loss (vomiting, diarrhea), fistula drainage, diabetes insipidus, or diuresis.
- fluid moves out of the vascular space into extravascular space (interstitial or intravascular space) called third spacing, as in leaks from surgical sites into abscess pockets, loss of blood volume into fracture site, burns and ascites.
- physiological consequences
- 1. decreased venous return to heart
- 2. decreased preload
- 3. decreased stroke volume
- 4. decreased cardiac output
- clinical signs:
- fall in BP
- blood flow shunted
- - renin activation in kidneys
- - impaired motility and slowing of peristalsis in GI tract
- - arterial oxygen levels drop with increased rate and depth of respiration in lungs
- Progressive Stage
- increased systemic interstitial edema
- renal: increased BUN and creatinine levels, increased urine specific gravity
- cerebral: anxiety, confusion, agitation, altered mentation, decreased level of consciousness
- cardiopulmonary: decreased BP, orthostatic hypotension, tachycardia, tachypnea, dysrhythmias, decreased CVP and PAWP, weak and thready pulses, decreased SpO2, crackles
- GI: decreased bowel sounds, paralytic ileus, hyper/hypo-glycemia
- hepatic: increased liver enzymes (e.g. AST, ALT) and lactate
- peripheral: decreased peripheral pulses, cool and clammy skin, decreased capillary refill, pallor or cyanosis
Hypovolemic Shock - Treatment
- * Monitor vital signs, orthostatic blood pressure, mental status, and urinary output
- * Monitor trends in hemodynamic parameters (e.g. CVP, PAP, PAWP) to assess patient's status and detect fluid deficits or excesses and to evaluate patitent's response to treament.
- * Volume expansion with administration of appropriate fluid to maintain blood pressure and cardiac output
- * Monitor for symptoms of respiratory failure (e.g. low PaO2, elevated PaCO2 levels, respiratory muscle fatigue) to plan respiratory interventions.
- * Monitor fluid status, including I/O
- * Monitor renal function (e.g. BUN, creatinine levels)
- * Provide O2 therapy and/or mechanical ventilation to maximize oxygenation and maintain SaO2 > 90%
- * Monitor blood glucose levels.
modified Trendenlenburg position
IVs with not only crystalloids but also colloids and/or blood products. Note: Lactated Ringers solution should be used cautiously because failing liver cannot convert lactate to bicarbonate leading to increased serum lactate levels
protect against fluid replacement hypothermia by warming fluid
fluid resuscitation in hypovolemic shock is initally calculated 3:1 rule (3ml of isotonic crystalloid for every 1ml of estimated blood loss)
dopamine (Intropin) can increase cardiac output; to treat hypotension; to increase urine output; increases renal perfusion, glomerular filtration rate, sodium excretion and urine output; inhibits insulin secretion
Vasopressin is an exogenous preparation of ADH; causes potent vasoconstriction leading to increased blood pressure without associated tachycardia and arrhytmias present by b-adrenergic stimulation
dobutamine causes vasodilation from beta2 stimulation which decreases afterload and improves myocardial contraction without massive increases in hearte rate and blood pressure; hypotension may occur if vasodilation is not offset by an increase in cardiac output.
Vasodilators (e.g. nitroglycerin, nitroprusside) are a type of vasoactive drugs used clinically to treat hypertension, prodiced controlled hypotension, and decrease left ventricular (systemic) myocardial workload; decrease systemic BP by decreasing systemic vascular resistance, venous return and cardiac output. Nitroprusside leads to a risk of cyanide toxicity; need to replace Q24h
Central Venous Pressure (CVP) Monitoring
is a reflection of blood volume and reflects right heart filling pressure
distal tip of catheter is positioned in superior vena cava just above the atrium
- normal range for CVP is 2-8 cm H2O or 2-6mm Hg
- hypovolemia and shock decrease CVP; fluid overload, vasoconstrictive states and cardiac tamponade increase CVP
has one-way valces in the side ports with a reservoir bag attached; prevens exhaled CO2 from getting into reservoir. Does not allow for rebreathing of exhaled air. Prevents the inhalation of room air and the re-inhalation of exhaled air.
allows for the administration of high concentrations of oxygen, 60–90% O2
for patients who require high-flow oxygen, but do not require breathing assistance; patients who are unable to breathe on their own would require an active breathing device, such as a bag valve mask or endotracheal tube.