16: 7-year-old female with abdominal pain and vomiting

Question 1

Children have a higher risk of dehydration than adults because they have

Answer 1

• Higher surface area:body mass ratio; hence, a greater relative area for evaporation to occur
• Higher basal metabolic rates than adults, which generates heat and expends water, and
• Higher percentage of body weight that is water (in infants, 70% of body weight is water; in children, 65%; and in adults, 60%).

Question 2

The diagnostic criteria for DKA are:

Answer 2

• A random blood glucose of > 200 mg/dL (> 11.1 mmol/L)
• A venous pH < 7.3 or serum bicarbonate < 15 mEq/L (< 15 mmol/L), and
• Moderate or large ketonuria or ketonemia.

Question 3

four ways to diagnose diabetes mellitus

Answer 3

1. A patient may be diagnosed with diabetes if he/she has symptoms of diabetes (polyuria, polydipsia, and unexplained weight loss) plus a random (any time of day, without regard to time since last meal) plasma glucose concentration > 200 mg/dL (11.1 mmol/L).
2. A patient can also be diagnosed with diabetes mellitus with a fasting (no caloric intake for at least 8 hours) blood glucose > 126 mg/dL (7.0 mmol/L).
3. A patient can also be diagnosed with diabetes mellitus with a 2-hour postload glucose of > 200 mg/dL (11.1 mmol/L) during an oral glucose tolerance test.
4. A HbA1c ≥ 6.5% in an adult is diagnostic of diabetes. T

Question 4

DKA should be suspected in pediatric patients who present with the following signs and symptoms

Answer 4

Vomiting
Weight loss
Dehydration
Shortness of breath
Abdominal pain, or
Change in the level of consciousness.

Question 5

When circulating blood glucose levels reach ~180 mg/dL

Answer 5

an osmotic diuresis occurs, leading to hypovolemia, dehydration, and a loss of sodium, potassium, and phosphate in the urine

Question 6

Laboratory Abnormalities in DKA

Answer 6

• pH on a venous blood gas dec
• serum Na dec
• K nml
• bicarb dec
• Cr elevated
• serum glucose elevated
• serum ketones and urine ketones elevated

Question 7

Types of dehydration: Isotonic/Isonatremic (Na = 130-150 mEq/L [130-150 mmol/L])

Answer 7

• This is the m/c type of dehydration in children and occurs when sodium and water losses are balanced, including children presenting with acute gastroenteritis and diarrhea.
• Typically the deficit in isonatremic dehydration can be replaced over 12 hours.

Question 8

Types of dehydration:

Hypotonic/Hyponatremic (Na < 130 mEq/L [< 130 mmol/L])

Answer 8

• This type of dehydration occurs when sodium losses exceed those of water.
• This most commonly occurs when patients consume diluted fluids or water in the face of dehydration.
• Hyponatremia may also be the result of adrenal insufficiency.
• The deficit in hyponatremic dehydration is typically replaced evenly over 24 hours.
• Rapid correction of hyponatremia is associated with central pontine myelinolysis (a neurologic disease caused by damage of the myelin sheath of nerve cells in the brainstem, more precisely in the area termed the pons, the most common cause of which is the too-rapid correction of hyponatremia.

Question 9

Types of dehydration: Hypertonic/Hypernatremic (Na > 150 mEq/L [> 150 mmol/L])

Answer 9

• This type of dehydration occurs when water losses exceed that of sodium and is associated with the highest mortality.
• Possible causes of hypernatremic dehydration include breastfeeding failure, use of inappropriate rehydration solutions (boiled milk), and diabetes insipidus.
• The deficit in hypernatremic dehydration is typically replaced evenly over 48 hours.
• Too-rapid correction of hypernatremia is associated with the development of cerebral edema.

Question 10

The pathophysiology of cerebral edema is poorly understood, but epidemiologic research has identified several risk factors:

Answer 10

• High BUN concentration at presentation
• Profound acidosis with hypocapnia
• Attenuated rise in the measured serum sodium with treatment, and
• Administration of bicarbonate.

Question 11

T2DM Risk Factors

Answer 11

• Obesity: Type 2 DM in children is more strongly associated with obesity than with any other clinical condition. Most studies have found that mean body mass index (BMI) among children with type 2 DM is >95th reference percentile for age.
• Ethnicity: more prevalent in Native American, African American, Latino, Asian American, Pacific Islander populations.
• Age: Peak age at diagnosis in youth is between 12 and 16 years (midpuberty)
• Sex (female; 3:1)
• Sedentary lifestyle

Question 12

Using the Glasgow Coma Scale, a score is assigned in each of three categories

Answer 12

Best eye-opening response
Best verbal response
Best motor response

Question 13

Adjusted verbal response criteria for children under the age of 5 years:

Answer 13

5 - Smiles, orientated to sounds, follows objects, interacts
4 - Cries but consolable, inappropriate interactions
3 - Inconsistently inconsolable, moaning
2 - Inconsolable, agitated
1 - No verbal response

Question 14

In a patient with dehydration and tachycardia

Answer 14

resuscitation with an IV fluid bolus is crucial. Fluid resuscitation should begin quickly with an IV fluid bolus of isotonic (0.9%, aka normal, saline) at 20 mL/kg over 60 minutes to begin to restore intravascular volume.

Question 15

next step is to try to identify or exclude the potentially life-threatening conditions on the differential diagnosis

Answer 15

• -A bedside capillary blood glucose measurement (fingerstick) will quickly identify two treatable causes of altered mental status, hypo- and hyperglycemia. The presence of hypoglycemia could point to a metabolic abnormality or toxic ingestion as potential causes.
• -Placing such a pt on a continuous CV monitor is important for monitoring response to therapy and identifying potentially lethal cardiac rhythm disturbances
• -A UA will be helpful in quickly identifying glucosuria or ketonuria or suggesting urinary tract/kidney infection. Urine may also be sent for evaluation of toxins.
• -A blood gas and electrolyte panel will identify metabolic derangements that need immediate correction, and may also help to make the diagnosis.

Question 16

Insulin Administration

Answer 16

• An insulin drip (0.1 units/kg/hour) should be started after the patient has received initial volume expansion, usually about 1 hour after starting fluids. (An insulin drip is typically started at the same time as maintenance plus replacement IV fluids.)
• Bicarbonate should not be given routinely because of the well-described paradoxical CNS acidosis and hypokalemia from rapid correction of acidosis. In addition, bicarbonate administration has been associated with an increased risk of cerebral edema, the most common cause of diabetes-associated death in children.
• Although K should be added eventually to the IV fluids, it should not be added until the serum K level is known.
• An insulin bolus is generally not recommended in children because it has also been associated with an increased risk of cerebral edema and could cause the glucose to drop too rapidly.
• After the initial fingerstick, glucose levels should be monitored carefully (every 30 minutes to 1 hour initially).

Question 17

Provide bolus fluids to restore intravascular volume

Answer 17

This is accomplished with a 10-20 mL/kg bolus of 0.9% saline (isotonic or “normal” saline). The general recommendation for patients who are not in DKA or renal failure is to provide serial boluses until the patient urinates. However, patients in DKA typically start urinating very shortly after providing fluid boluses due to osmotic diuresis (this occurs in diabetes when the serum glucose concentration exceeds the renal threshold for glucose reabsorption [> 180mg/dL], leading to glucosuria and obligate loss of water, sodium and potassium, not because they have received enough resuscitation fluids. Therefore, patients in DKA should be monitored for improvement of their vital signs (normalized heart rate and blood pressure) and mental status.

Question 18

correct dehydration

Answer 18

The amount of fluid required to replace the patient’s deficit is dictated by your assessment of the degree of dehydration (3-5%, 6-10% or 11-15%). The composition of fluid (0.3% saline, 0.45% saline, 0.9% saline, etc.) and rate of infusion is dictated by the serum sodium concentration/osmolarity. In hyponatremic dehydration a sodium deficit is calculated, and in hypernatremic dehydration a free water deficit is calculated.

Question 19

Provide maintenance fluids

Answer 19

In addition to the fluids required to replace the fluid deficit, patients with dehydration must also be provided with maintenance fluids. Maintenance fluids replace daily insensible losses (perspiration and respiration) and normal urine output (approximately 2.0 mL/kg/hr for children < 15 kg and 1.0 mL/kg/hr for children > 15 kg and adults). Insensible losses account for approximately 40% of daily maintenance needs, while normal urine output accounts for about 60%. In general, 0.25% saline (1/4 normal saline) or 0.45% saline (1/2 normal saline) with 5-10% dextrose is used to provide maintenance fluids.

Question 20

Replace ongoing losses

Answer 20

In many patients with dehydration, the losses may continue, even after replacement therapy has begun. Therefore, careful attention must be paid to monitoring the patient’s output and vital signs, to determine the need for additional replacement. The amount and type of replacement fluid is determined by the source of the losses. For example, in gastroenteritis with ongoing diarrhea, stool output that exceeds 1.0 g/kg/hr should be replaced every 4 to 6 hours with 0.45% saline (1/2 normal saline). Additional examples of ongoing losses are emesis, nasogastric tube output, increased insensible losses due to fever, and tachypnea.

Question 21

There are three methods of calculating maintenance fluids

Answer 21

By caloric expenditure
By body surface
The Holliday-Segar method

Question 22

The Holliday-Segar method is probably the easiest to remember.

Answer 22

• -100 mL/kg/day for the first 10 kg of body weight
• -50 mL/kg/day for the second 10 kg of body weight
• -20 mL/kg/day for each additional 1 kg of body weight

Question 23

Admission Orders for Patient in DKA

Answer 23

• continuous monitoring of vitals
• hourly neuro checks
• monitors I and Os
• insulin orders
• –Patient will continue on the insulin drip until the acidosis has resolved (bicarbonate > 15 mEq/L [> 15 mmol/L] or a normal anion gap) and the patient is ready to transition to subcutaneous insulin.
• serum glucose every 60 mins
• serum ca, mg, and phosphorous now
• check serum pH (VBG) every 60 mins
• urine dipstick for ketones

Question 24

every insulin regimen has the same two components:

Answer 24

• -Basal insulin: An intermediate- to long-acting preparation to suppress hepatic glucose production and maintain normoglycemia in the fasting state.
• -Prandial insulin: Doses of short-acting insulin taken before meals and/or snacks to cover the expected carbohydrate load from the food intake.

Question 25

Traditional Regimen

Answer 25

2/3 of the total dose in the morning (1/3 rapid or short-acting, 2/3 intermediate-acting [e.g., NPH])
1/6 of the total at dinner as rapid or short-acting insulin, and
1/6 of the total before bed as intermediate-acting insulin.

Question 26

“Basal-bolus” Therapy

Answer 26

• -Half of the total daily dose is given in the form of an “ultra-long-acting” basal insulin given at bedtime (e.g., insulin glargine, which lasts for upwards of 24 hours), and
• -Half is split evenly among all 3 meals.

Question 27

The initial total daily dose of insulin varies with weight, age, pubertal status, and presence or absence of DKA.

Answer 27

• -Children recovering from DKA may require up to 1 unit/kg per day of insulin.
• -Children without DKA at presentation may be treated with 0.25 to 0.75 unit/kg per day, depending on age and pubertal status.

Question 28

Patients with type 1 diabetes have an increased risk of

Answer 28

other autoimmune related diseases, with autoimmune thyroid disease and celiac disease being the most common

Question 29

Differential Diagnosis of Vomiting and Altered Mental Status: DKA (1/8)

Answer 29

• -Vomiting-usually precipitated by the acidosis-is often a presenting symptom, as are increased respiratory rate and vague abdominal pain.
• -A preceding history of enuresis and polydipsia is strongly suggestive of newly presenting diabetes.
• -Unless a coincident infection precipitates ketosis and thus a presentation for medical evaluation, one does not expect to see fever in a child with DKA.
• -Diffuse abdominal pain is characteristic, a consequence of the ongoing acidosis.
• -Significant dehydration is a prominent feature due to a combination of vomiting and osmotic diuresis.
• -AMS is often a result of dehydration and/or electrolyte abnormalities; its presence should make one consider whether or not there is concurrent cerebral edema.
• -Tachypnea is a normal physiologic response to attempt to compensate for the acidosis in DKA, which is purely a metabolic acidosis.

Question 30

Differential Diagnosis of Vomiting and Altered Mental Status: Toxic ingestions (2/8)

Answer 30

• -Toxic ingestion often results in vomiting, altered mental status, and obtundation.
• -Dehydration is possible depending on the extent of vomiting and the degree to which any change in mental status impairs oral intake.
• -Aspirin overdose may present with tachypnea.
• -Abdominal pain may be seen in toxic ingestions-in an overdose of iron, for example.

Question 31

Differential Diagnosis of Vomiting and Altered Mental Status: GI obstruction (3/8)

Answer 31

• -Vomiting, sometimes bilious, is commonly seen in GI obstruction.
• -Almost all patients with obstruction will be dehydrated; the degree of dehydration depends on degree of vomiting.
• -Abdominal pain is a prominent feature of GI obstruction.
• -Altered mental status is unlikely unless dehydration is severe.

Question 32

Differential Diagnosis of Vomiting and Altered Mental Status: Inc ICP (4/8)

Answer 32

> > Increased ICP often presents with vomiting.
Rarely, a tumor might cause a central diabetes insipidus.
A patient with increased ICP may exhibit an altered level of consciousness, often preceded/accompanied by headache.

Question 33

Differential Diagnosis of Vomiting and Altered Mental Status: Gastroenteritis (5/8)

Answer 33

• -Gastroenteritis is the most common cause of vomiting; it may be viral or bacterial.
• -It usually also presents with fever, colicky abdominal pain, and diarrhea.
• -Dehydration is common in gastroenteritis.

Question 34

Differential Diagnosis of Vomiting and Altered Mental Status: Appendicitis (6/8)

Answer 34

–Abdominal pain is a prominent symptom of appendicitis, classically migrating to the RLQ

Question 35

Differential Diagnosis of Vomiting and Altered Mental Status: Bacterial PNA (7/8)

Answer 35

• -The possibility of pneumonia should be investigated in any child presenting with abdominal pain (can be caused by inflammation of the pleura).
• -If the patient becomes septic, can see a diminished level of consciousness.
• -Signs of dehydration, if present, are mild.

Question 36

Differential Diagnosis of Vomiting and Altered Mental Status: Pyelonephritis (8/8)

Answer 36

> > Vomiting may be seen in pyelonephritis and may lead to dehydration.
It would be important to distinguish between urinary frequency-which one might expect in the case of pyelonephritis-and polyuria, which should not commonly be present.

Question 37

signs of cerebral edema

Answer 37

irregular respirations, headache, vomiting, third nerve palsy, and high blood pressure.

Question 38

A 9-year-old male presents to the ED in an ambulance after he was found unconscious at a local playground. In the ED he is arousable but extremely obtunded. He is able to minimally verbalize that his head hurts and his stomach feels uncomfortable. He states the pain is constant and non-radiating. He vomits clear liquid twice over the course of 30 minutes. Vital signs are as follows: T 37.6 C, P 66 bpm, BP 155/80 mm Hg, RR 18 bpm. You further notice that his breathing is irregular with brief episodes of apnea. On physical exam you are unable to reproduce the abdominal pain and there is no rebound tenderness or guarding. The rest of the physical exam is unremarkable. What is the most likely diagnosis?

Answer 38

This is the correct choice. Increased ICP can be secondary to epidural or subdural hemorrhage. It is possible the patient may have fallen while playing in the playground. Increased ICP can present as the classic Cushing’s triad: hypertension, inappropriate slowing of the heart rate, and irregular respirations (Cheyne-Stokes respiration). A further complication of increased ICP is epigastric discomfort. This is caused by the elevated ICP causing vagal stimulation, resulting in the secretion of gastric acid. Lastly, the patient’s headache and non-bilious vomiting can also be ascribed to the increased ICP.

Question 39

most common causes of a small bowel obstruction

Answer 39

adhesions from a previous surgery or a hernia

Question 40

A 7-year-old boy is brought by ambulance to the ED with altered consciousness. The EMT said he found the boy in a pool of vomit. He is unable to answer questions coherently and he is alone. Physical exam findings indicate dry mucous membranes, tachypnea, tachycardia, and moaning on palpation of the abdomen. His physical exam is otherwise normal, including a normal blood pressure. What is the most likely cause of his condition?

Answer 40

DKA typically presents with altered mentation, vomiting, dehydration, and abdominal pain. The history will yield polydipsia and polyuria during the days preceding DKA. Metabolic acidosis causes tachypnea as the body tries to blow off CO2 through a compensatory respiratory alkalosis.

Question 41

Potassium in DKA

Answer 41

In diabetic ketoacidosis, the acidosis and lack of insulin cause potassium to leave cells and enter the serum, causing an elevated serum potassium level. However, as the DKA is corrected and insulin is administered, the potassium will re-enter the cells, causing a decreased serum potassium level, so potassium levels should be monitored closely when therapy is initiated.