Monthly Archives: October 2013

Immunocompromised Surgical Patients Highlight Notes

Immunocompromized, Pearls, Surgical Catheters, Transplantation, Typhlitis, , ,

Immunocompromised surgical patients

  • Sirolimus slows down wound healing.  Consider switching transplant patients to a different immunosupressive drug to limit wound healing problems.
  • Patients on Sirolimus also exhibit higher post operative complications of seromas, hernias, and wound dehiscence.
  • We have gotten away from the practice of administering stress dose steroids on most general surgery patients on maintenance steroids
  • Avoid placing hemodialysis catheters if possible because of the short-term and long-term complications.
  • Most likely wouldn’t remove a catheter just for a febrile episode on hemodialysis.  But if the patient is septic – still try to maintain the catheter if possible.
  • UNOS = united network of organ sharing.  When an organ donor is identified, the info is sent to UNOS who then generate a list of possible recipients.
  • Travel outside of the US.  Big question is who is the donor?
  • Organ trafficking is illegal in the US.  But not illegal to take care of the patient postop in the US after the patient had gone overseas.
  • AV fistulas are considered to be better than AV grafts – short-term and long term.
  • Peritoneal Dialysis use is expanding – many people who weren’t considered eligible in the past are now eligible.
  • Immunosuppression increases the risk for cancer.
  • Typhlitis, non-surgical protocol is used whenever possible when the patient is not toxic.  Typhlon = cecum (Greek).  Necrotizing enterocolitis, neutropenic enterocolitis., caecitis.  Typhlitis affects immunocompromized patients such as those undergoing chemotherapy, patients with AIDS, transplant patients, or the elderly.

Surgical Care Highlights

Critical Care, Fondaparinux, Neostigmine, Perioperative, , ,

Surgical Care – Perioperative

  • “Never Events” Root cause analysis needed – surgery at wrong site or wrong patient
  • Circulating nurses see things differently than surgeons
  • Tight glucose control blood glucose 90-110 mg/dl is associated with higher mortality rate in post operative patients than liberal control  <180.
  • statement that  >age 60 all need stress test – not valid
  • PEG tubes has risk of cellulitis
  • Removal of the distal ileum removal steatorrhea, impaired vitamin B12 absorption, and calcium oxalate stones.
  • Immunization is not needed hemisplenectomy and nonoperative spleen salvage.
  • Patient co-morbidities dictates BKA vs. AKA.  AKA has higher mortality rate.
  • Hepatic cirrhosis is now relative rather than absolute contraindication laparoscopic cholecystectomy
  • Dehydration occurs after some bowel preps
  • Sepsis and dilution from massive transfusions cause thrombocytopenia than heparin induced thrombocytopenia.
  • Day 1 post op – can consider feeding younger healthy patients, after colon surgery.
  • Today, PA catheters are reserved for cardiac surgery patients and occasional major vascular case with significant CAD and heart dysfunction.
  • Contrast induced nephropathy is at highest risk in patients who are hypotensive, chronic renal disease, or congestive heart failure.
  • Metformin (Glocophage) – Guidline for withdrawal prior to surgery:  discontinue for at least a day, and then RESTART 2-3 days after po intake (after surgery).  Discontinued before surgery because during withdrawal lactic acidosis can develop high Mortality >50% if not adequately treated.
  • Beta blockade may increase stroke risk in high risk cardiac patients
  • Hyperkalemia (medical emergency, manage cardiac effects) – quickest way to manage:  give calcium gluconate IV.  On the other hand IV glucose and Insulin useful for shifting potassium into the cell but needs >30 minutes to be effective.  Calcium gluconate doesn’t have effects on potassium levels in the blood, it reduces the excitability of cardiomyocytes.
  • In patients who present for emergent surgery with drug eluting stents that have been in place for at least three months, dual aspirin and plavix therapy is maintained.
  • Atrial Fib:  Amiodarone or metoprolol after 48 hours can result in good blood pressure results however the patients may still be in atrial fibrillation.  Atrial Fibrillation may correct itself with volume status and electrolyte correction.
  • Febrile patients with Staph infection on their central line and blood  – remove their central line catheter as their first line of defense.
  • Technical errors occur more often in simple / routine procedures than complicated ones.
  • DVT in the arm – location (proximal vs. distal) doesn’t matter in risk of PE.
  • Insulin drips (perioperative to maintain glucose control) should be done in the ICU or other monitored setting.
  • Hemostatic agents – gel foam with bovine thrombin – are used in the OR for coagulation.
  • Give FFP (fresh frozen plasma) when using cell saver for autotransfusion – because when processing blood in the cell saver, there is some depletion of coagulation factors.
  • Let alcohol dry before operating to prevent fires.
  • Hip fracture patients – get them to OR urgently for repair; otherwise there’s morbidities associated with bed rest.
  • Betablockers can be cardioprotective, but take precautions in giving beta blockers to patients with bradycardia, heart blocks, heart failure
  • Mechanical bowel prep doesn’t add much to infection reduction in colon surgeries
  • MRSA can even be found in skin abscesses of patients who have NOT been exposed to antibiotics.
  • NG tubes should be removed as soon as possible to maximize coughing ability and pulmonary toilet.
  • Neostigmine causes motility and contraction of the colon – give only if distal colon is not obstructed.
  • Fondaparinux seems to have equal ability to prevent DVT compared to other heparin formulations.  Trade name Arixtra.  Chemically related to low molecular weight heparins.  Fondaparinux is a synthetic Factor Xa inhibitor.

Perioperative General Surgery Highlights

Critical Care, ICU, Pearls, Perioperative, , , , , ,

Perioperative ICU Topics

Transfusion related acute lung injury must be distinguished from cardiogenic and non cardiogenic pulmonary edema and pulmonary contusion.

  • TRALI – acute onset of non-cardiogenic pulmonary edema after transfusion of blood products.
  • Leading cause of transfusion related fatalities in the US
  • Occurs within first 6 hours following transfusion
  • Due to leukocyte antibodies in transfused plasma
  • Incidence 1:5000

Transfusion related circulatory overload – diurese early

  • Furosemide is a loop diuretic

Intubated patients should be transported in Semi fowler recumbent position, 30 degree head of bead to help prevent ventilator associated pneumonia

  • Semi fowler – knees bent, head of bed not as high as fowler position

Hydration of the patient is an important measure to prevent contrast induced nephropathy

With ICU patients with Renal insufficiency, aggressive dialysis does not lead to significant improvements in renal recovery and 30 day mortality rates

Analgesics and sedatives may blunt ACTH stimulation test for adrenal insufficiency

  • ACTH stim test for asessing the functioning of adrenal glands.
  • ACTH is made by the anterior pituitary gland which stimulates the adrenal glands to release cortisol, DHEAS, and aldosterone.
  • Adrenal insufficiency is a potentially life threatening problem
  • ACTH stimulation test is primarily used to deterine the presence of Addison’s diaseas and pituitary impairment
  • Addison’s disease: Adrenal glands do not produce sufficient steroid hormones.  Also known as primary adrenal insufficiency.
  • The test is extremely sensitive to primary adrenal insufficiency but less so to secondary adrenal insufficiency.  Secondary adrenal insufficiency is caused by deficiency of ACTH.

Precedex:  use less than 24-48 hours.

  • Dexmedetomidine – a sedative used in ICU which does not cause respiratory depression

Outcomes protonics vs. H2 blockers not that different in stress gastritis prophylaxis

Advanced directives in ICU – pastoral care staff to bring up on initial contact

Family like ICU rounds – transparency

Refeeding syndrome – low phosphate levels is a hallmark.  Happens in 10 days or more of not feeding.  When feeding resumes:  hyperglycemia – creates even lower levels by moving phosphate and potassium into cells.

Abdominal Compartment Syndrome – open abdomen immediately with elevated intra-abdominal pressure and renal failure, hypotension, or high pulmonary ventilation pressures.

Use of diuretics in ACS (Abdominal Compartment Syndrome) is controversial.  Some surgeons diurese early to decrease bowel edema and to get the abdomen closed.

ICU central lines to be assessed daily and document need for it daily

Trauma patients, erythropoetin may predispose to DVT

  • Liver production of erythropoetin predominates in the fetal and perinatal period
  • Renal production is dominant during adulthood

Induced coma clouds the issue of brain death in regards to organ donation.

Elderly ICU with hyperactive delirium have better outcomes than those with hypoactive delirium.

Elevated CK levels hallmark in propofol infusion syndrome.

  • Potentially and often fatal
  • cardiac failure, rhabdomyolysis, renal failure, hyperkalemia, hypertriglycerdemia, hepatomegaly.
  • Maybe caused by impaired mitochondrial function
  • CK = creatine kinase = present in all muscles
  • Elevated CK levels indicated muscle damage/strain – could be from heart attack or muscles being overworked (ie. weight lifting).
  • Propofol infusion syndrome is at higher risk when patients are already on catecholamines or corticosteroids.

Inhaled PGE2, selectively vasodiates the pulmonary vasculature, it improves VQ mismatch in severe hypoxemia

  • An area with no ventilation (V/Q = zero) = shunt
  • The area with no perfusion = dead space
  • PGE2 = prostaglandin E2
  • PGE2 softens cervix and causes uterine contraction, causes fever, direct vasodilator, relaxes smooth muscles.

In sepsis, norepinephrine raises heart rate less than dopamine.

  • Vasoactive drug use in septic shock
  • Used to increase blood pressure
  • Dopamine is the immediate precursor of norepinephrine and epinephrine
  • Less tachycardic reaction with NorEpinephrine compared to Dopamine.

Trauma Pearls

Pearls, Trauma, Uncategorized
  • 2 incision fasciotomy for compartment syndrome of extremity fractures – a common problem is incision is made too far laterally to help the anterior compartment (missed)
  • After 24-48 h of open abdomen management,  fistula rate is approx 15% if abdomen is not closed.
  • If stable hemothorax – 24-48 h to see if evac.  By day 2-3 it would be increasingly difficult to evacuate blood beyond that time, thorascopically.
  • Thoracic aortic injuries.  Endovascular repair typically not used in young patients or less than 20mm diameter aorta.
  • Complication of LMA = vomiting
  • Splenic injury, > or = 20% do not heal in three months.
  • Elderly patients with elevated INR, small head bleed on coumadin.  Rx with early plasma infusions, and early factor 7A use.
  • Carotid injuries do not occur commonly in easily accessible locations; put patient on antiplatelet  therapy and most of these injuries will heal.
  • Serial cardiac enzymes are rarely needed in patients with suspected blunt cardiac injury.
  • Zone I retroperitoneal hematomas = central periaorta hematomas.  Explore gun shot wound Zone I retrperitoneal hematomas even without expanding hematoma.
  • To evaluate  distal perfusion, proximity GSW to both extremities, use ankle brachial index rather than arterial pressure index.  (The API is the ratio between systolic blood pressures measured distal to a penetrating injury in one extremity and the systolic pressure measured at the same location in the contralateral uninjured extremity.)
  • solid organ injury, CT vascular extravasation should not determine management approach – instead depend on hemodynamics.
  • Injury to kidney after blunt trauma – prefer nonoperative treatment for better renal salvage even with urinary extravasation.
  • Head trauma, small epidural hematoma, no other injuries, observation in ICU x 24h – neuro exams, and repeat CT in 6h.
  • Leg with crush type wound with venous injury.  Re-establish blood flow quickly with shunt.  Tie a suture around shunt, do not debride the vessel back before placing shunt because the vessel will be injured more with the shunt tying.
  • Blunt traumatic arrest cases – not likely to survive to discharge from hospital.   Consider terminating resusitation.
  • Comatose patients, can remove cervical-collar if a good helical CT scan of the spine is completely normal.
  • A true transpelvic GSW (gunshot wound) should go to OR even with (or without) gross blood on rectal exam.
  • Complication and mortality rates  with rib fractures are twice higher in elderly patients than younger patients.
  • Physical exam with seatbelt sign is often not helpful, small bowel injury association is not 100%.
  • Side curtain airbags are more helpful than frontal airbags for additional protection in addition to seatbelts which do not do as well with lateral movement.
  • —-

Insulinoma

Insulinoma,

Tumor of the beta cells of the pancreas

  • secretes insulin
  • Normally beta cells secrete insulin in response to high glucose in the blood stream.
  • Diagnosis is made with blood tests of low blood glucose, elevated insulin, and elevated proinsulin and C-peptide levels.
  • Steve Jobs of Apple died of Metastatic Insulinoma.
  • rarely malignant, metastasis and primary usually present concomitantly.
  • finding insulinoma near the pancreatic duct – this insulinoma might be malignant

Whipples Triad suggests insulinoma

  1. Symptoms of Hypoglycemia
  2. Low plasma glucose
  3. Relief of symptoms when glucose is raised to normal

Sestamibi scan

Hyperparathyroidism, Sestamibi Scan

Sestamibi Parathyroid Scan

  • It’s a nuclear scan to localize parathyroid adenomas.
  • Tc99m-sestamibi is absorbed faster by a hyperfunctioning parathyroid gland
  • Allows the surgeon to remove the one gland of the 4 parathyroids which is hyperfunctioning – minimally invasive parathyroidectomy.
  • Sestamibi scan only detects only about 70% of HPT lesions.  So don’t discard the diagnosis of HPT when the sestamibi scan is negative.
  • Hyperparathyroidism is the excess of parathyroid hormone (PTH) in the blood stream.  Primary hyperparathyroidism (Primary HPT) has lab values of high calcium and high PTH.  Secondary hyperparathyroidism has lab values of low calcium and high PTH.  Most common cause of secondary HPT is chronic renal failure.  (treatment is possibly renal transplantation).
  • Sestamibi scan is to detect parathyroid hyperfunctioning which then is a cause of primary HPT.

 

Secondary HPT

Endocrine, Hungry Bone Syndrome, Hypocalcemia, Parathyroid hormone, Secondary hyperparathyroidism, Vitamin D,

Secondary Hyperparathyroidism

  • excessive PTH secreted by parathyroid glads in response to hypocalcemia.
  • Seen in chronic renal failure (most common cause of secondary HPT)
  • Bone and joint pain are common
  • Parathyroid hypertrophy
  • no role for parathyroid surgery
  • Vitamin D deficiency can cause secondary HPT

Normal calcium level with elevated PTH

Normal calcium blood levels with an elevated PTH might be due to vitamin D levels.  Low vitamin D levels lead to elevated PTH levels to help maintain normal calcium blood levels.

Chronic Renal Failure

  • Failing kidneys fail to convert enough vitamin D to its active form
  • Does not adequately excrete phosphate into the urine
  • Insoluble calcium phosphate forms in the body which removes calcium from the circulation – thus hypocalcemia and thus increases parathyroid hormone in an attempt to increase serum calcium levels

Other causes besides renal failure

  • Malabsorption dependent bariatric surgery
  • malabsorption due to chronic pancreatitis, small bowel disease

What is tertiary hyperparathyroidism?

Tertiary hyperparathyroidism occurs when the correction of the underlying cause will not stop excess PTH secretion

Vitamin D and Calcium?

The body needs vitamin D to absorb calcium from our diet.

What is primary hyperparathyroidism?

  • Increased PTH secretion and raised serum calcium levels
  • 85% caused by parathyroid adenoma (usually only one gland affected)
  • 10% caused by chief cell hyperplasia

What is hungry bone syndrome?

  • Severe Hypocalcemia seen after surgical correction of HPT
  • Chronically deprived bone aggressively absorbs calcium

MIBG

Adrenal, MIBG scan, Pheochromocytoma,

Useful when cross-sectional imaging is negative and an ectopic pheochromocytoma is suspected.

What is an MIBG scan

  • Uses a radiactive substance (tracer) and a scanner to find the presence of pheochromocytoma or neuroblastoma.
  • MIBG is the radioisotope.  metaiodobenzylguanidine
  • Patients are sometimes given an iodine mixture to prevent the thyroid gland from absorbing too much of the radioisotope.
  • 90% sensitive for detection of pheochromocytomas
  • FDOPA (fluoro-Dopa) PET/CT scan is also available for the detection of pheochromocytomas

 Pheochormocytomas typically show evidence of hyperintensity on T2 weighted MRI.

Exposing the right sided adrenal gland

Adrenalectomy, , , , ,

Right Triangular Ligament of the Liver

  • Take down the right triangular ligament of the liver to expose the right adrenal gland.
  • Gland is right next to the vena cava (IVC = inferior vena cava)

Open right adrenalectomy

  • Mobilize the right lobe of the liver and the hepatic flexure of the colon
  • Enter the retroperitoneum
  • Reflect the duodenum and head of pancreas medially (Kocher maneuver)
  • The Kocher maneuver exposes the right adrenal gland and inferior vena cava.

Ectopic ACTH production

Cancer, Cushing's Syndrome, Ectopic ACTH, Lung, Medullary Thyroid Cancer, ,

Ectopic ACTH Syndrome

Also known as EAS

Sources of Ectopic ACTH production.

  • Lung = most common cause.
  • Thymus
  • Thyroid – Medullary carcinoma
  • Ovary
  • Adrenal Gland – pheochromocytoma
  • Liver
  • Pancreas
  • Other neuroendocrine cancers

Difference between Cushings syndrome and Cushings disease

  • Cushings syndrome is cortisol excess from any cause.
  • Cushings disease is cortisol excess by pituitary ACTH over-secretion

Presentation found on the internet regarding Ectopic ACTH production:

http://www.med.unc.edu/medicine/web/ectopicacth.pdf

Subclinical Cushing Syndrome

Adrenalectomy, Diabtetes, Endocrine, Hypertension, Subclinical Cushing's Syndrome, Uncategorized

What is subclinical cushing’s syndrome?

  • subclinical hypercortisolism / may be observed with adrenal incidentaloma
  • autonomous clucocorticoid production without specific signs and symptoms of Cushing’s syndrome.
  • Much more common than classic Cushing’s syndrome
  • Patients have a high prevalence of obesity, hypertension, and type 2 diabetes.
  • Patients with incidentally detected adrenal masses who are about to undergo surgery should have testing for subclinical Cushing’s to avoid postoperative adrenal crisis..
  • Best test is short dexamethasone suppression test.

What is Cushing’s syndrome?

  • exaggerated facial roundness,
  • weight gain around the midsection and upper back
  • thinning of arms and legs.
  • stretch marks
  • hypertension
  • diabetes
  • Cushing’s syndrome occurs when exposed to high levels of the hormone cortisol for an extended period of time.
  • this can either occur with taking too much corticosteroid medication or when the body makes too much cortisol.
  1. Pituitary adenoma – secreting excess ACTH which stimulates the adrenal glands to make more cortisol
  2. Ectopic ACTH secreting tumor (ie. Lungs, pancreas, thyroid or thymus gland)
  3. Primary Adrenal Gland disease
  4. Familial Cushing syndrome

Diabetes type 1 vs. type 2

Type 1 = immune disorder.  Body attacks and destroys insulin producing beta cells in the pancreas.  Must take insulin.  Sometimes called insulin dependent or juvenile onset diabetes.

Type 2 = either the body doesn’t produce enough insulin or the cells ignore the insulin (resistant).  Sometimes called adult onset diabetes.  Obesity is the strongest risk factor for type 2 diabetes.

Adrenalectomy for subclinical Cushing’s Syndrome?

http://onlinelibrary.wiley.com/doi/10.1111/j.1365-2265.2011.04253.x/pdf

Adrenalectomy may lead to cure or better control of diseases associated with subclinical Cushing’s syndrome such as diabetes and hypertension

 Adrenal Incidentalomas

Most pose no clinical problems.

Post operative hypocalcemia

Endocrine, Hypocalcemia, Parathyroid hormone, Thyroid,

Low Calcium after thyroidectomy

  • Most common complication after total or near total thyroidectomy is hypocalcemia due to hypoparathyroidism.  Post thyroidectomy hypoparathyroidism is usually related to disruption of the blood supply to parathyroid glands.
  • A patient needs only a single healthy parathyroid gland to have normal parathyroid function.

Symptoms of hypocalcemia

  • Could be asymptomatic or show up as:
  • mild paresthesias
  • Painful tentany
  • muscle aches
  • weakness or twitching
  • Larngeal spasm
  • Arrythmia

PTH

  • Parathyroid hormone measurement after surgery.  Possibly consider this protocol.  If less than 10 (pg/ML) supplement with calcium and calcitriol.  If between 10-20 supplement with calcium.  If greater than 20 – then no supplementation.
  • PTH is secreted by the chief cells of the parathyroid gland.
  • Acts to increase the concentration of calcium in the blood
  • PTH half life is about 4 minutes.

what is Calcitriol?

  • Hormonally active form of vitamin D.
  • After thyroidectomy, supplimentation with Calcitriol may supress PTH levels.

A main reason for hospitalization overnight after  total thyroidectomy

To monitor for the risk of hypocalcemia.

What is Octreotide

Carcinoid Syndrome, Octreotide, Pancreatic fistulas, Prophylaxis, Somatostatin, Whipple

Octreotide

  • Sandostatin is the brand name – by Novartis
  • Mimics natural somatostatin pharmacologically
  • But is more potent inhibitor of growth hormone, glucagon, and insulin than somatostatin.
  • May be considered a treatment in carcinoid syndrome.
  • The prophylactic use of perioperative octreotide does not reduce the incidence of pancreatic fistula or complications after pancreaticoduodenectomy (Whipple).  Reference:  http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1421155/ – article from the year 2000: Does Prophylactic Octreotide Decrease the Rates of Pancreatic Fistula and Other Complications After Pancreaticoduodenectomy?

What is a Gastrointestinal Stromal Tumor (GIST)

Cancer, Gastrointestinal Stromal Tumor, GIST, Uncategorized

GIST – Gastrointestinal Stromal Tumor

  • GISTs may be malignant or benign
  • More common in the stomach and small intestine but can be found anywhere along the GI tract.
  • Begins in cells called th interstitial cells of Cajal (ICC) – considered the pacemakers of the GI tract
  • GIST may have a genetic component.  Neurofibromatosis type 1 is linked to GIST.
  • Partial resections are usually adequate with GIST treatment with negative margins.  Formal gastrectomy is not usually necessary, nor is partial gastrectomy with nodal dissection.  Organ sparing approaches are usually appropriate.

What is a Petersen’s Hernia after Roux-en-Y Gastric Bypass?

Gastric Bypass, Internal Hernia, Laparoscopic Surgery, Petersen's Hernia, Roux-en Y, Weight Loss Surgery

Petersen’s Hernia

  • A form of internal hernia (usuall through iatrogenic defects from prior surgery)
  • Can be found after Roux-en Y Gastric Bypass surgeries (a form of WLS: weight loss surgery)
  • The Petersen’s Hernia is found between the transferse colon mesentery and the mesentery of the segement of Jejunum
  • It is the herniation of intestinal loops through the defect between the small bowel limbs, the transverse mesocolon and the retroperitoneum.
  • Laparoscopic surgery is a risk factor for this type of hernia because of fewer post operative adhesions.