Complex Care Exam 2

Describe an intestinal obstruction.

Occurs when intestinal contents cannot pass through the GI tract

• Partial or complete

• Simple or strangulated

Explain the difference between a partial and complete obstruction

Partial: Obstructions do not completely occlude the intestinal lumen, allowing for some fluid and gas to pass through

Complete: Totally occludes the lumen, usually requires surgery

Explain the difference between a simple and strangulated obstruction

Simple: has intact blood supply

Strangulated: no intact blood supply

Explain the difference between a mechanical and non-mechanical obstruction

Mechanical: a physical obstruction of the intestinal lumen

Non-mechanical: Reduced or absent peristalsis due to altered neuromuscular transmission of the parasympathetic innervation to the bowel

Mechanical obstruction causes

• Hernia

• Strictures from IBD

• Intussusception

Non-mechanical obstruction causes (intestinal and colon)

• Neuromuscular or vascular disorder

Mechanical colon obstruction causes:

• Colorectal cancer

• Diverticular disease

• Sigmoid volvulus: bowel twists on itself

Describe how a hernia, stricture, and intussusception can cause an obstruction

Hernia

• Intestine pushes past weakened abdominal wall and becomes trapped

Stricture

• narrowing of the intestine, caused by scar tissue build-up on the intestinal wall

• From Crohn’s or surgical adhesions/scar tissue

Intussusception

• part of the intestine folds into another part, obstructing food passage

Describe how cancer, diverticula, and volvulus can cause an obstruction

Colorectal cancer

• Tumor grows and causes obstruction

Diverticular disease

• irregular, bulging pouch in the colon wall block passage of stool

Sigmoid volvulus

• bowel twists on itself, becomes strangulated

Explain the pathophysiologic processes that occur with an obstruction

• When an obstruction occurs, fluid, gas, and intestinal contents accumulate proximal to the obstruction. 

• Distal to the obstruction, the bowel empties and then collapses

• Pressure increases proximal to obstruction and causes increase in capillary permeability

  • Leads to extravasation of fluids and electrolytes into the peritoneal cavity

• Eventually the intestinal muscle becomes fatigued, and peristalsis stops

• If blood flow is inadequate, bowel tissue becomes ischemic, then necrotic, and the bowel may perforate

• Retention of fluids in the intestine and peritoneal cavity leads to a severe reduction in circulating blood volume

  • Ends with hypotension and hypovolemic shock

Define the four hallmark clinical manifestations associated with a bowel obstruction

• Abdominal pain

• Vomiting

• Distention

• Constipation or marked change in bowel status

Explain the importance of auscultating all four quadrants of the abdomen. What would you hear?

• Bowel sounds can be present and become progressively hypoactive

• may reveal high-pitched sounds above the area of obstruction

• Bowel sounds are usually absent with paralytic ileus

Describe colicky pain

sharp, localized gastrointestinal or urinary pain that can arise abruptly, and tends to come and go in spasm-like waves

Describe the vomit associated with small bowel obstruction (high and lower)

High/proximal:

• N/V develops rapidly

• may be projective and contain bile

• usually provides temporary relief from abdominal pain in higher obstructions

Lower/distal:

• more gradual in onset

• more fecal and foul smelling

Explain the acid-base imbalance associated with intestinal obstruction

• If the obstruction is high: metabolic alkalosis

  • loss of gastric hydrochloric (HCl) acid through vomiting or NG intubation and suction

Explain the diagnostic changes present with an intestinal obstruction

• CT scans and abdominal x-rays can identify obstruction 

• Sigmoidoscopy or colonoscopy may provide direct visualization of an obstruction in the colon

• elevated WBC count may indicate strangulation or perforation

• Elevated hematocrit values may reflect hemoconcentration

• Decreased hemoglobin and hematocrit values may indicate bleeding from a neoplasm or strangulation with necrosis

• Serum electrolytes, BUN, and creatinine are monitored frequently to assess the degree of dehydration

• Metabolic alkalosis can develop from vomiting

Explain the purpose of an NG tube for intestinal obstruction

• Decompression

• Patient placed on NPO status

Explain why Lactated ringers and normal saline would be used for intestinal obstruction

• To rehydrate 

• Use isotonic fluids (not replacing electrolytes)

Explain why a stent would be part of the treatment plan for intestinal obstruction

Stents are used for palliative purposes or as “a bridge to surgery,” allowing a patient to avoid emergency surgery

• gives interprofessional care team time to correct fluid volume problems and treat other problems, thus improving surgical outcomes

Explain the nursing implications associated with an intestinal obstruction

• early recognition of deterioration in the patient's condi­tion– electrolyte imbalances, hypovolemic shock

• Strict I+Os

• Determine the location, duration, intensity, and frequency of abdominal pain

• Record the onset, frequency, color, odor, and amount of vomitus. 

• Assess bowel function and sounds, including the passage of flatus

• Inspect the abdomen for scars, visible masses, and distension

• Palpate for tenderness vs rigidity 

• Measure abdominal girth daily

• Check for signs of peritoneal irritation: guarding, rebound pain, pain if bed is shaken

• Check the NG tube every 4 hours for patency.

• Frequent teeth brushing, mouthwash, rinse with water

What are the two primary labs to be assessed for when a patient receives total parenteral nutrition? What complication can occur in the vascular system when a patient receives TPN? Why?

• Labs: blood glucose levels and electrolytes

• Complications

  • thrombosis, and catheter occlusion

  • Infection and sepsis 

  • Endothelial damage 

  • Hyperglycemia and high triglyceride levels 

What are preload, afterload, and contractility

• Preload: volume of blood in the ventricles at the end of diastole (volume/stretch)

• Afterload: Resistance the left ventricle must overcome to eject blood into the aorta during systole 

Contractility: ability of the heart to contract and function as a pump

How do hemodynamics affect SV, CO, HR

• SV: affected by preload, afterload, and contractility 

• CO: affected by heart rate and stroke volume

• HR: First determinant and influencer of cardiac output 

  • Affected by medications, dysrhythmias, and nervous system

Know the relationship between SV, CO, HR

CO=SV*HR

Appreciate the CO calculation: expected compensatory changes or findings

• HR rapidly compensates for changes in CO

• Increased preload leads to increased CO (until a certain point)

• Preload is the most significant influence on stroke volume

• Very increased or decreased afterload leads to decreased CO

• Increased contractility leads to decreased CO

Hemodynamic values that can be directly monitored

• Intra-arterial blood pressure

• Central venous pressure

• Pulmonary artery pressure (PAWP/PAOP)

• Mixed venous oxygen saturation

Hemodynamic values that can be calculated

• MAP

• SVR

• PVR

What measures preload: left

• Left: Left ventricular end diastolic pressure

  • pulmonary capillary pressure and left atrial pressure

  • Pulmonary artery wedge pressure (PAWP) aka pulmonary artery occlusive pressure (PAOP) 

What measures preload: right

• Right: Right ventricular end diastolic pressure

  • measured by right atria

  • Central venous pressure (CVP)

What factors increase and decrease preload

volume in ventricles at end of diastole

What conditions increase preload

• HF

• CKD

• cardiogenic shock

• hypervolemia c/b fluid overload

• excess dietary salt intake

• Pregnancy

What conditions decrease preload

• Diuresis (directly), hypovolemia, hemorrhage,

• ascites, burns

• Venous vasodilation (indirectly)

medications that decrease preload

• diuretics

• nitrates

• ACE inhibitors and ARBs

• some CCBs

What measures afterload: left

• Left ventricular afterload: 

  • resistance of blood flow encountered by the left ventricle 

  • Measured by systemic vascular resistance (SVR)

What measures afterload: right

• Right ventricular afterload: 

  • resistance of blood flow encountered by the right ventricle 

  • Measured by pulmonary vascular resistance (PVR)

What factors increase and decrease afterload

Affected by arteriole size: vasoconstriction vs vasodilation

What conditions increase SVR

• HTN

• vasopressors

• aortic stenosis

• hypothermia

• SNS response

What conditions decrease SVR

• Depressed SNS response

• septic shock, anaphylactic shock, neurogenic shock

What conditions increase and decrease PVR

• Increase PVR

  • Pulmonary HTN

  • hypoxia

  • PE

  • pulmonary stenosis

• Decrease PVR

  • Medications 

What medications decrease afterload

• milrinone

• vasodilator medications (ex. nitroglycerin)

What factors increase and decrease contractility

• Medications 

• Changes in preload 

• Autonomic nervous system 

• Electrolyte imbalances  

• Clinical conditions

Medications that increase contractility

• Positive inotropes

• epinephrine, norepinephrine, 

• dopamine, dobutamine, 

• digitalis-like drugs (digoxin)

• Calcium

• Milrinone

Medications that decrease contractility

• Negative inotropes: 

• Calcium channel blockers

• Beta blockers

What conditions increase contractility

• Increased preload: fluid or blood administration

• Electrolyte imbalances

• SNS activation

What conditions decrease contractility

• Hypoxemia

• PNS activation

• Acidosis, hypercapnia

• HF

Define hemodynamic parameters: CO, SV, CI, MAP

• Cardiac output: volume of blood pumped by the heart in 1 minute

• Stroke volume: the volume of blood pumped out of the left ventricle with each contraction

• Cardiac index: measurement of CO adjusted for body surface area

• Mean arterial pressure: measure of tissue perfusion 

List non-invasive findings to assess hemodynamic status

• Preload

  • Fluid status: JVD or flat, urine output, skin turgor

• Afterload

  • vasoconstriction/vasodilation: BP, MAP, skin temp and color, capillary refill

• Contractility

  • Pulse strength and rate

  • Capillary refill

Levophed/norepinephrine for hemodynamics

• Positive inotrope: Increases BP and CO

  • Increases SVR (afterload) and preload

• Can be used to treat shock

• If given too much:

  • severe HTN

  • arrhythmias

  • headaches

  • tissue damage

Sodium nitroprusside for hemodynamics 

• Vasodilator: reduces afterload and preload

• Lowers BP

• Variable effects on CO

Nitroglycerin for hemodynamics 

• Vasodilator: reduces afterload and preload

• Lowers BP and cardiac O2 demand, improves CO

NS for hemodynamics 

• Increases intravascular volume → increases preload and CO

• Can have adverse effects of acidosis and AKI

What effect do moderate increased and decreased preload have on CO?

• Increased preload → increased CO

• decreased preload → decreased CO

What effect do extremely increased and decreased preloads have on CO?

• Extremely increased preload → decreased CO

  • Too much myocardial stretch, decreases contractility 

• Extremely decreased preload → decreased CO

What effect do extremely increased and decreased afterloads have on CO?

• Extremely increased afterload → decreased CO

  • Increased vasoconstriction, becomes too difficult to pump

• Extremely decreased afterload → decreased CO

  • Vasodilation leads to not enough force to pump

What is the Monro-Kellie doctrine, and how does it relate to increased intracranial pressure?

• states that the three components must remain relatively constant within the closed skull structure. 

• If the volume of any of the three components increases within the cranial vault and the volume from another component is displaced, the total intracranial volume will not change, but the pressure will increase instead

What is the normal range for ICP? What level is considered pathologic?

• Normal: 5-15 mmHg supine

• Pathological: sustained pressure over 20 mmHg

How is ICP measured and where?

• Pressure transducer in the following locations:

  • Ventricles

  • Subarachnoid space

  • Subdural space

  • Epidural space

  • Brain tissue

What specific vital sign and specific body system will be most affected if there are sustained increases in the ICP affecting the brainstem? What will you expect to see because you know this vital sign can be affected?

• Brainstem is the respiratory center

• Will see decrease RR or irregular respirations 

• Respiratory arrest can occur

What is the difference between primary and secondary brain injury?

Primary: Occurs at the initial time of an injury

Secondary: The resulting injury from the brain moving and hitting the opposite side of the skull

• can occur several hours to days after the initial injury

What is the most sensitive indicator of a patient’s neurologic status?

• LOC is the most sensitive and reliable indicator of the patient's neurologic status

• patient's state of consciousness is defined by the patient's clinical responses and pattern of brain activity (done using EEG)

What are some changes the RN may see with LOC when a person has increased ICP?

• Flat affect

• change in orientation

• Decrease in attention level

• Coma

How will the RN know if the patient is in a coma? What is present/absent?

• Coma- the deepest state of unconsciousness

• The patient does not respond to painful stimuli.

• Corneal and pupillary reflexes are absent. 

• The patient cannot swallow or cough

• incontinent of urine and feces

• The EEG pattern demonstrates suppressed or absent neuronal activity

What does the Glasgow Coma Scale assess? What are the three things that are measured?

• Assesses LOC after brain injury 

1. Eye opening: spontaneous, to sound, to pressure, none

2. Verbal response: oriented, confused, words, sounds, none

Motor response: commands, type of movement

What are the three changes that would indicate that a patient is experiencing Cushing’s triad?

• Systolic hypertension with a widening pulse pressure

  • SBP minus DBP gets larger

• Bradycardia with a full and bounding pulse

• Irregular respirations

What does the presence of Cushing’s triad indicate?

• medical emergency: sign of brainstem compression and impending death

• Often doesn’t appear until ICP has been increased for some time or is very high

What changes occur with the temperature during Cushing’s triad, and why?

A change in body temperature may also occur because increased ICP can affect the hypothalamus (usually a fever)

What specific changes may be present with the person’s eyes and vision when they have increased ICP? What could these changes indicate?

• Unequal pupils

• Diplopia

• Doll’s eye dysfunction

• Papilledema – swelling of the optic nerve

• Fixed, unilateral, dilated pupil: indicates brain herniation

What is the significance of raccoon eyes and bruising over the mastoid process?

• Raccoon eyes- severe bruising around the eyes

• Battle sign- bruising over the mastoid process

• can indicate a basilar skull fracture, and the injury is a significant deep internal injury

• Injury is deeper in the brain tissue than it appears!!

What is the difference between decorticate and decerebrate posturing? Which is more severe? Why is it more severe?

Decorticate

• Arms flexed in towards core 

• Extension of the legs with plantar flexion 

• Indicates damage to the corticospinal tract (nerve pathway in the midbrain that connects the brain and spinal cord)

Decerebrate 

• Arms extended and hyperpronated, at sides

• Legs hyperextended with plantar flexion

• Indicates more extensive brain damage

  • Deeper parts of brain that control vital autonomic functions

Describe the headache associated with increased ICP.

• nocturnal headache and/or a headache in the morning is cause for concern and may indicate a tumor or other space-occupying lesion that is causing increased ICP

•  Straining, agitation, or movement may accentuate the pain

Describe the vomiting associated with increased ICP.

• usually not preceded by nausea (unexpected vomiting)

• Projectile vomiting may also occur

What diagnostic study is contraindicated when a patient has increased ICP? Why is it contraindicated?

• In general, a lumbar puncture is not performed when increased ICP is suspected

• Cerebral herniation could occur from the sudden release of the pressure in the skull from the area above the lumbar puncture

What are the purposes and benefits of a patient having a ventriculostomy?

• gold standard for monitoring ICP 

• A specialized catheter is inserted into the lateral ventricle and coupled to an external transducer

• Directly measures the pressure within the ventricles

• Facilitates removal and/or sampling of CSF

• Allows for intraventricular drug administration

What are some BASIC nursing concerns associated with the patient having a ventriculostomy? What will you assess based on these concerns?

• Inaccurate readings: assess for reasons

• Routinely assess the insertion site

• Infection: CSF should always be clear

  • Higher chance when in over 5 days or have leak or systemic infection

What are some reasons why there may be an inaccurate reading from the ventriculostomy?

• CSF leaking around catheter causing lower reading

• Obstruction of the intraventricular catheter (from tissue or blood clot)

• Kinks in the tubing

• Height difference between catheter and transducer

• Incorrect height of drainage system

• Bubbles or air in tubing

What is mannitol, and why is it used in the treatment of increased ICP?

• osmotic IV diuretic

• Creates a gradient that pulls fluid into blood vessels from tissues to reduce ICP

What are some potential complications related to mannitol?

• Affect hematocrit levels and blood viscosity 

• Need to monitor fluid and electrolyte status

• Neuro status: brain doesn’t handle quick fluid shifts well

• Contraindicated in renal disease

Why are corticosteroids used in the treatment of increased ICP? Corticosteroids have two primary functions.

2 primary functions:

• Suppress inflammation

• suppress immune system

Adverse effects of long term corticosteroid use

• Hyperglycemia

• Increased risk for infections

• GI bleeding

• Hypernatremia

Why are barbiturates used in the treatment of increased ICP?

Patient shivering/shaking from dysregulated temperature control → barbiturates used to sedate patient to reduce metabolic workload of brain

What nutritional requirement is increased when a patient has increased ICP? Why?

• Increased need for glucose (hypermetabolic/catabolic state)

• Enteral or parenteral nutrition started if oral intake inadequate 

  • Nutritional replacement usually begins within 3 days after injury