Flashcards in Complications Deck (169):
What is atelectasis?
Collapse of the alveoli
What is the etiology of atelectasis?
Inadequate alveolar expansion, high levels of inspired oxygen
What are the signs of atelectasis?
Fever, decreased breath sounds with rales, tachypnea, tachycardia, and increased density on CXR
What are the risk factors for atelectasis?
COPD, smoking, abdominal or thoracic surgery, over-sedation, poor pain control
What is the most common cause of fever during PODs #1 and #2?
What prophylactic measures can be taken against atelectasis?
Preoperative smoking cessation, incentive spirometry, good pain control
What is the treatment for atelectasis?
Postoperative incentive spirometry, deep breathing, coughing, early ambulation, NT suctioning, and chest PT
What is postoperative respiratory failure?
Respiratory impairment with increased respiratory rate, SOB, dyspnea
What is the differential diagnosis for postoperative respiratory failure?
Hypovolemia, PE, administration of supplemental O2 to a patient with COPD, atelectasis, pneumonia, aspiration, pulmonary edema, abdominal compartment syndrome, PTX, chylothorax, hemothorax, narcotic overdose, mucous plug
What is the treatment for postoperative respiratory failure?
Supplemental O2, chest PT, suctioning, intubation, and ventilation if necessary
What is the initial workup for postoperative respiratory failure?
ABG, CXR, EKG, pulse oximetry, and auscultation
What are the indications for intubation and ventilation in postoperative respiratory failure?
Cannot protect airway (unconscious), excessive work of breathing, progressive hypoxemia (PaO2 < 55 despite supplemental O2), progressive acidosis (pH < 7.3 and PCO2 > 50), RR > 35
What are the possible causes of postoperative pleural effusion?
Fluid overload, pneumonia, diaphragmatic inflammation with possible subphrenic abscess formation
What is the treatment of postoperative wheezing?
Why may it be dangerous to give a patient with chronic COPD supplemental O2?
This patient uses relative hypoxia for respiratory drive, and supplemental O2 may remove the drive
What is a pulmonary embolism?
DVT that embolizes to the pulmonary arterial system
What is DVT?
Deep Vein Thrombosis:
A clot that forms in the pelvic or lower extremity veins
Is DVT more common in the right or left iliac vein?
Left is more common (4:1) because the aortic bifurcation crosses and possibly compresses the left iliac vein
What are the signs and symptoms of DVT?
Lower extremity pain, swelling, tenderness, Homan's sign, PE.
Up to 50% are asymptomatic.
What is Homan's sign?
Calf pain with dorsiflexion of the foot seen classically with DVT, but actually found in fewer than 33% of patients with DVT
What test is used to evaluate for DVT?
What is Virchow's triad?
2. Endothelial injury
3. Hypercoagulable state
What are the risk factors for DVT and PE?
Postoperative status, multiple trauma, paralysis, immobility, CHF, obesity, OCPs, tamoxifen, cancer, advanced age, polycythemia, MI, HIT syndrome, hypercoagulable state (protein C/ protein S deficiency)
What are the signs and symptoms of PE?
SOB, tachypnea, hypotension, chest pain, occasionally fever, loud pulmonic component of S2, hemoptysis with pulmonary infarct
What are the associated lab findings with PE?
ABG: decreased PO2 and PCO2 (from hyperventilation)
Which diagnostic tests are indicated for PE?
CT angiogram, VQ scan, pulmonary angiogram
What are the associated CXR findings with PE?
1. Westermark's sign (wedge-shaped area of decreased pulmonary vasculature resulting in hyperlucency)
2. Opacity with base at pleural edge from pulmonary infarction
What are the associated EKG findings with PE?
> 50% are abnormal.
Classic finding is cor pulmonale (S1Q3T3 RBBB and right-axis deviation).
EKG most commonly shows flipped T waves or ST depression.
What is a saddle embolus?
PE that straddles the pulmonary artery and is in the lumen of both the right and left pulmonary arteries
What is the treatment for PE if the patient is stable?
Anticoagulation (heparin followed by long-term warfarin) or Greenfield filter
What is a Greenfield filter?
Metallic filter placed into IVC via jugular vein to catch emboli prior to lodging in the pulmonary artery
When is a Greenfield filter indicated?
If anticoagulation is contraindicated or patient has further PE on adequate anticoagulation or is high risk (e.g. pelvic or femur fractures)
What is the treatment for PE if the patient's condition is unstable?
Consider thrombolytic therapy.
Consult thoracic surgeon for possible Trendelenburg operation.
Consider catheter suction embolectomy
What is the Trendelenburg operation?
Pulmonary artery embolectomy
What is a retrievable IVC filter?
IVC filter that can be removed
What percentage of retrievable IVC filter are actually removed?
What prophylactic measures can be taken for DVT/PE?
LMWH 40 mg SQ QD or 30 mg SQ bid; subQ heparin (5000 units q8h); sequential compression device boots beginning in OR; early ambulation
What is aspiration pneumonia?
Pneumonia following aspiration of vomitus
What are the risk factors for aspiration pneumonia?
Intubation/extubation, impaired consciousness, dysphagia, nonfunctioning NGT, Trendelenburg position, emergent intubation with full stomach, gastric dilatation
What are the signs and symptoms of aspiration pneumonia?
Respiratory failure, chest pain, increased sputum production, fever, cough, mental status changes, tachycardia, cyanosis, infiltrate on CXR
What are the associated CXR findings with aspiration pneumonia?
Early: fluffy infiltrate or normal CXR
Late: pneumonia, ARDS
Which lobes are commonly involved in aspiration pneumonia?
Which organisms are commonly involved in aspiration pneumonia?
Community acquired: gram-positive/mixed
Hospital: gram-negative rods
Which diagnostic tests are indicated for aspiration pneumonia?
CXR, sputum, Gram stain, sputum culture, bronchoalveolar lavage
What is the treatment for aspiration pneumonia?
Bronchoscopy, antibiotics if pneumonia develops, intubation if respiratory failure, ventilation with PEEP if ARDS
What is Mendelson's syndrome?
Chemical pneumonitis secondary to aspiration of stomach contents (i.e. gastric acid)
Are prophylactic antibiotics indicated for aspiration pneumonia?
What are possible NGT complications?
Aspiration pneumonia, atelectasis, sinusitis, minor UGI bleeding, epistaxis, pharyngeal irritation, gastric irritation
What are the risk factors for gastric dilatation?
Abdominal surgery, gastric outlet obstruction, splenectomy, narcotics
What are the signs and symptoms of gastric dilatation?
Abdominal distension, hiccups, electrolyte abnormalities, nausea
What is the treatment for gastric dilatation?
What do you do if you have a patient with high NGT output?
Check high AXR and, if the NGT is in duodenum, pull back the NGT into stomach
What is postoperative pancreatitis?
Pancreatitis resulting from manipulation of the pancreas during surgery or low blood flow during the procedure (i.e. cardiopulmonary bypass), gallstones, hypercalcemia, medications, idiopathic
What lab tests are performed for postoperative pancreatitis?
Amylase and lipase
What is the initial treatment for postoperative pancreatitis?
Same as that for the other causes of pancreatitis (e.g. NPO, aggressive fluid resuscitation, +/- NGT PRN)
What are the postoperative causes of constipation?
What is the treatment for constipation?
What is OBR?
Ortho Bowel Routine:
Docusate sodium (daily), dicacodyl suppository if no bowel movement occurs, Fleet enema if suppository is ineffective
What is short bowel syndrome?
Malabsorption and diarrhea resulting from extensive bowel resection (< 120 cm of small bowel remaining)
What is the initial treatment for short bowel syndrome?
TPN early, followed by many small meals chronically
What causes SBO?
Adhesions (most of which resolve spontaneously), incarcerated hernia (internal or fascial/dehiscence)
What causes ileus?
Laparotomy, hypokalemia or narcotics, intraperitoneal infection
What are the signs of resolving ileus/SBO?
Flatus PR, stool PR
What is the order of recovery of bowel function after abdominal surgery?
1. Small intestine
When can a postoperative patient be fed through a J-tube?
From 12-24 postoperative hours because the small intestine recovers function first in that period
What are the pre-hepatic causes of postoperative jaundice?
Hemolysis (prosthetic valve), resolving hematoma, transfusion reaction, post-cardiopulmonary bypass, blood transfusions (decreased RBC compliance leading to cell rupture)
What are the hepatic causes of postoperative jaundice?
Drugs, hypotension, hypoxia, sepsis, hepatitis, "sympathetic" hepatic inflammation from adjacent right lower lobe infarction of the lung or pneumonia, preexisting cirrhosis, right-sided heart failure, hepatic abscess, pylephlebitis (thrombosis of portal vein), Gilbert syndrome, Crigler-Najjar syndrome, Dubin-Johnson syndrome, fatty infiltrate from TPN
What are the post-hepatic causes of postoperative jaundice?
Choledocholithiasis, stricture, cholangitis, cholecystitis, biliary-duct injury, pancreatitis, sclerosing cholangitis, tumors (e.g. cholangiocarcinoma, pancreatic cancer, gallbladder cancer, metastases), biliary stasis (e.g. ceftriaxone)
What blood test results would support the assumption that hemolysis was causing jaundice in a patient?
Decreased: haptoglobin, Hct
Increased: LDH, reticulocytes
Also, fragmented RBCs on a peripheral smear
What is blind loop syndrome?
Bacterial overgrowth in the small intestine
What are the causes of blind loop syndrome?
Anything that disrupts the normal flow of intestinal contents
What are the surgical causes of B12 deficiency?
Blind loop syndrome, gastrectomy (decreased secretion of intrinsic factor), excision of the terminal ileum (site of B12 absorption)
What is post-vagotomy diarrhea?
Diarrhea after a truncal vagotomy
What is the cause of post-vagotomy diarrhea?
After truncal vagotomy, a rapid transport of bile salts to the colon results in osmotic inhibition of water absorption in the colon, leading to diarrhea
What is dumping syndrome?
Delivery of hyperosmotic chyme to the small intestine causing massive fluid shifts into the bowel (normally the stomach will decrease the osmolality of the chyme prior to its emptying)
With what conditions is dumping syndrome associated?
Any procedure that bypasses the pylorus or compromises its function (i.e. gastroenterostomies or pyloroplasty).
Thus, dumping of chyme into the small intestine.
What are the signs and symptoms of dumping syndrome?
Postprandial diaphoresis, tachycardia, abdominal pain and distention, emesis, increased flatus, dizziness, weakness
How is the diagnosis of dumping syndrome made?
History, hyperosmolar glucose load will elicit similar symptoms
What is the medical treatment for dumping syndrome?
Small, multiple, low-fat/low-carb meals that are high in protein content.
Also, avoidance of liquids with meals to slow gastric emptying.
Surgery is a last resort.
What is the surgical treatment for dumping syndrome?
Conversion to Roux-en-Y (+/- reversed jejunal interposition loop)
What is a reversed jejunal interposition loop?
Segment of jejunum is cut and then reversed to allow for a short segment of reversed peristalsis to slow intestinal transit
What is diabetic ketoacidosis?
Deficiency of body insulin, resulting in hyperglycemia, formation of ketoacids, osmotic diuresis, and metabolic acidosis
What are the signs of DKA?
Polyuria, tachypnea, dehydration, confusion, abdominal pain
What are the associated lab values with DKA?
Elevated glucose, increased anion gap, hypokalemia, urine ketones, acidosis
What is the treatment for DKA?
Insulin drip, IVF rehydration, K supplementation, +/- bicarbonate IV
What electrolyte must be monitored closely in DKA?
Potassium and hypokalemia (corrections of acidosis and glucose/insulin drive K into cells and are treatment for hyperkalemia)
What must you rule out in a diabetic with DKA?
Infection (perirectal abscess is classically missed)
What is Addisonian crisis?
Acute adrenal insufficiency in the face of a stressor (i.e. surgery, trauma, infection)
What is the cause of Addisonian crisis?
Postoperatively, inadequate cortisol release usually results from steroid administration in the past year
What are the signs and symptoms of Addisonian crisis?
Tachycardia, N/V/D, abdominal pain, +/- fever, progressive lethargy, hypotension, eventual hypovolemic shock
Clinically, what is infamous about Addisonian crisis?
Tachycardia and hypotension refractory to IVF and pressors
Which lab values are classic for Addisonian crisis?
Decreased Na, increased K (secondary to decreased aldosterone)
What is the treatment for Addisonian crisis?
IVFs (D5 NS), hydrocortisone IV, fludrocortisone PO
What is fludrocortisone?
What is SIADH?
Syndrome of Inappropriate AntiDiuretic Hormone
What does ADH do?
ADH increases NaCl and H2O resorption in the kidney, increasing intravascular volume (released from posterior pituitary)
What are the causes of SIADH?
CNS trauma, oat-cell lung cancer, pancreatic cancer, duodenal cancer, pneumonia, lung abscess, increased PEEP, stroke, general anesthesia, idiopathic, postoperative, morphine
What are the associated lab findings with SIADH?
Low sodium, low chloride, low serum osmolality, increased urine osmolality
How can the serum sodium level in SIADH be remembered?
SIADH = Sodium Is Always Down Here = hyponatremia
What is the treatment for SIADH?
Treat primary cause, restrict fluid intake
What is diabetes insipidus?
Failure of ADH renal fluid conservation resulting in dilute urine in large amounts
What is the source of ADH?
What are the 2 major types of diabetes insipidus?
1. Central DI
2. Nephrogenic DI
What is the mechanism of the 2 types of DI?
1. Central: decreased production of ADH
2. Nephrogenic: decreased ADH effect on kidney
What are the classic causes of central DI?
Brain injury, tumor, surgery, infection
What are the classic causes of nephrogenic DI?
Amphotericin B, hypercalcemia, chronic kidney infection
What lab values are associated with DI?
Hypernatremia, decreased urine sodium, decreased urine osmolality, increased serum osmolality
What is the treatment for DI?
Fluid replacement, follow Na levels and urine output.
Nephrogenic: consider thiazide diuretics
What are the arterial line complications?
Infection; thrombosis (which can lead to finger/hand necrosis); death/hemorrhage from catheter disconnection
What is the Allen test?
Measures for adequate collateral blood flow to the hand via the ulnar artery:
1. Patient clenches fist and clinician occludes radial and ulnar arteries
2. Patient opens fist and clinician releases only the ulnar artery
If the palm exhibits immediate strong blush upon release of ulnar artery, then ulnar artery can be assumed to have adequate collateral flow if the radial artery were to thrombose
What are the common causes of dyspnea following central line placement?
PTX, pericardial tamponade, carotid puncture (which can cause a hematoma that compresses the trachea), air embolism
What is the differential diagnosis of postoperative chest pain?
MI, atelectasis, pneumonia, pleurisy, esophageal reflux, PE, musculoskeletal pain, subphrenic abscess, aortic dissection, PTX, chylothorax, hemothorax, gastritis
What is the differential diagnosis of postoperative atrial fibrillation?
Fluid overload, PE, MI, pain (excess catecholamines), atelectasis, pneumonia, digoxin toxicity, hypoxia, thyrotoxicosis, hypercapnia, idiopathic, acidosis, electrolyte abnormalities
What is the most dangerous period for a postoperative MI following a previous MI?
Six months after an MI
What are the risk factors for postoperative MI?
History of MI, angina, Qs on EKG, S3, JVD, CHF, aortic stenosis, advanced age, extensive surgical procedure, MI within 6 months, EKG changes
How do postoperative MIs present?
Often without chest pain.
New onset CHF, new onset cardiac dysrhythmia, hypotension, chest pain, tachypnea, tachycardia, N/V, bradycardia, neck pain, arm pain.
What EKG findings are associated with cardiac ischemia/MI?
Flipped T waves, ST elevation, ST depression, dysrhythmias (e.g. new onset AFib, PVC, VTach)
Which lab tests are indicated with MI?
Troponin I, cardiac isoenzymes (elevated CK mb fraction)
What is the treatment for postoperative MI?
Nitrates (paste or drip), aspirin, oxygen, pain control with IV morphine, beta-blocker (as tolerated), heparin (possibly, thrombolytics are contraindicated in the postoperative patient), ICU monitoring
How can the treatment of postoperative MI be remembered?
BEta-blocker (as tolerated)
When do postoperative MIs occur?
66% occur on POD #2-5 (often silent and present with dyspnea or dysrhythmia)
What is a CVA?
CerebroVascular Accident (stroke)
What are the signs and symptoms of a CVA?
Aphasia, motor/sensory deficits usually lateralizing
What is the workup for a CVA?
Head CT (must rule out hemorrhage if anticoagulation is going to be used); carotid Doppler U/S (evaluate for carotid occlusive disease)
What is the treatment for a CVA?
ASA, +/- heparin if feasible postoperatively.
Thrombolytic therapy is not usually postoperative option.
What is the perioperative prevention of CVA?
Avoid hypotension; continue aspirin therapy preoperatively in high-risk patients if feasible; preoperative carotid Doppler U/S in high-risk patients
What is postoperative renal failure?
Increase in serum creatinine and decrease in creatinine clearance.
Usually associated with decreased urine output.
What is anuria?
< 50 cc urine output in 24 hours
What is oliguria?
Between 50-400 cc of urine output in 24 hours
What is the differential diagnosis for postoperative renal failure?
1. Inadequate blood perfusing kidney: inadequate fluids, hypotension, CHF.
2. Kidney parenchymal dysfunction: ATN, nephrotoxic contrast or drugs.
3. Obstruction to outflow of urine from kidney: Foley catheter obstruction/stone, ureteral/urethral injury, BPH, bladder dysfunction (e.g. medications, spinal anesthesia).
What is the workup for postoperative renal failure?
BUN, Cr, urine electrolytes/Cr, FENa, U/A, renal U/S
What is FENa?
Fractional Excretion of Na
What is the formula for FENa?
(Una / Pna) X (Pcr / Ucr) X 100
What is the BUN/Cr ratio in prerenal vs renal failure?
Prerenal: > 20:1
Renal: < 20:1
What is the urine specific gravity in prerenal vs renal failure?
Prerenal: > 1.020 (as body tries to hold on to fluid)
Renal: < 1.020 (kidney has decreased ability to concentrate urine)
What is the urine Na in prerenal vs renal failure?
Prerenal: < 20
Renal: > 40
What is the urine osmolality in prerenal vs renal failure?
Prerenal: > 450
Renal: < 300 mOsm/kg
What are the indications for dialysis in postoperative renal failure?
Fluid overload, refractory hyperkalemia, BUN > 130, acidosis, uremic complication (encephalopathy, pericardial effusion)
What is DIC?
Activation of the coagulation cascade leading to thrombosis and consumption of clotting factors and platelets and activation of fibrinolytic system (fibrinolysis), resulting in bleeding
What are the causes of DIC?
Tissue necrosis, septic shock, massive large-vessel coagulation, shock, allergic reactions, massive blood transfusion reaction, cardiopulmonary bypass, cancer, obstetric complications, snake bites, trauma, burn injury, prosthetic material, liver dysfunction
What are the signs and symptoms of DIC?
Acrocyanosis or other signs of thrombosis, then diffuse bleeding from incision sites, venipuncture sites, catheter sites, or mucous membranes
What are the associated lab findings with DIC?
Increased fibrin-degradation products, elevated PT/PTT, decreased platelets, decreased fibrinogen (level correlates well with bleeding), presence of schistocytes, increased D-dimer
What is the treatment for DIC?
Removal of cause; IVFs; O2; platelets; FFP; cryoprecipitate (fibrin); Epsilon-aminocaproic acid (as needed in predominantly thrombotic cases); heparin and antithrombin III (indicated in predominantly thrombotic cases as needed)
What is abdominal compartment syndrome?
Increased intra-abdominal pressure usually seen after laparotomy or after massive IVF resuscitation
What are the signs and symptoms of abdominal compartment syndrome?
Tight distended abdomen, decreased urine output, increased airway pressure, increased intra-abdominal pressure
How is intra-abdominal pressure measured?
Read intrabladder pressure (Foley catheter hook up to manometry after instillation of 50-100 cc of water)
What is normal intra-abdominal pressure?
< 15 mmHg
What intra-abdominal pressure indicates need for treatment?
> 25 mmHg, especially if signs of compromise
What is the treatment for abdominal compartment syndrome?
Release the pressure by placing drain and/or decompressive laparotomy (leaving fascia open)
What is a Bogata bag?
Sheet of plastic (empty urology irrigation bag or IV bag) used to temporarily close the abdomen to allow for more intra-abdominal volume
What is urinary retention?
Enlarged urinary bladder resulting from medications or spinal anesthesia
How is urinary retention diagnosed?
Physical (palpable bladder), PVR
What is the treatment for urinary retention?
With massive bladder distention, how much urine can be drained immediately?
Most would clamp after 1 L and then drain the rest over time to avoid a vasovagal reaction
What is the classic sign of urinary retention in an elderly patient?
What are the signs and symptoms of wound infection?
Erythema, swelling, pain, heat
What is the treatment for wound infections?
Open wound; leave open with wet-to-dry dressing changes; antibiotics if cellulitis present
What is fascial dehiscence?
Acute separation of fascia that has been sutured closed
What is the treatment for fascial dehiscence?
Bring back to the OR emergently for reclosure of the fascia
What is a wound hematoma?
Collection of blood (blood clot) in operative wound
What is the treatment for a wound hematoma?
Acute: Remove with hemostasis
Subacute: Observe (heat helps resorption)
What is a wound seroma?
Post-operative collection of lymph and serum in the operative wound
What is the treatment of a wound seroma?
Needle aspiration, repeat if necessary (prevent with closed drain)
What are the signs and symptoms of pseudomembranous colitis?
Diarrhea, fever, hypotension, tachycardia
What is the incidence of bloody diarrhea in pseudomembranous colitis?
What classic antibiotic causes C. difficile overgrowth?
Clindamycin (but almost all antibiotics can cause it)
How is pseudomembranous colitis diagnosed?
C. difficile toxin in stool, fecal WBC, flex sig (see a mucous pseudomembane in lumen of colon)
What is the treatment for pseudomembranous colitis?
1. Flagyl (PO or IV)
2. PO vancomycin if refractory to Flagyl