Normal heart rate for a child aged 6-12 is 70-120 bpm. This is moderately higher than normal heart rate for an adult, which is 60-100 bpm. 

Proper cuff size is very important for accurate blood pressure assessment. The correct way to determine proper blood pressure cuff size is to wrap the cuff around the arm, then note the area covered by the inflatable bladder. The inflatable bladder should cover approximately 80% of the circumference of the forearm while its width should cover approximately 40%. 

The chest-piece of the stethoscope is made up of two components designed for auscultation: the bell and the diaphragm. The bell is dome-shaped and used for auscultation of low-pitched sounds, while the diaphragm is used to auscultate high-pitched sounds.

A patient with a one-time high blood pressure reading can not be diagnosed as hypertensive. A diagnosis of hypertension requires at least three measurements of blood pressure over 140/90 mmHg on at least two separate visits to health care provider. 

Stage II hypertension is defined as a blood pressure equal to or greater than 160 mmHg systolic over 100 mmHg diastolic, taken at three different times on at least two separate occasions. Stage I hypertension is systolic blood pressure of 140-160 mmHg or diastolic blood pressure of 90-100 mmHg, while prehypertension is defined as a systolic blood pressure of 120-140 mmHg or diastolic blood pressure of 80-90 mmHg.

While most examiners remember to take the pulse, temperature, and blood pressure while assessing their patient's vitals, overall visual appearance is also an important part of an individuals vitals. Does the patient appear ill? Anxious? Are there any noticeable issues with hygiene or bizarre dress or movements? Are there any signs of pallor, jaundice, or cyanosis? All of these observations can be quickly noted in a patient's chart when taking vitals.

Tachycardia is the term used to describe a faster than normal heart rate. A heart rate of more than 100 beats per minute is considered tachycardic. Bradycardia is used to describe a slower than normal heart rate. Less than 60 beats per minute is considered bradycardia.

Afebrile is a term used to describe a patient who does not have a fever. Clinically, a fever is defined as a temperature greater than 100.4 Fahrenheit. Blood pressure, heart rate, and respiratory rate do not tell you if the patient has a fever.

The most likely cause of his symptoms is hypoglycemia, which is defined as a blood glucose below  in a non-diabetic patient. The symptoms of hypoglycemia include altered consciousness, tremors, weakness, vertigo, headaches, heart palpitations, and a bounding pulse.

A temperature of  is not considered abnormal as it may reflect a normal variation in body temperature.

His blood pressure is slightly elevated, but it is unclear whether this is typical for him or whether this represents a significant change from his normal blood pressure. Regardless it would not likely be sufficiently elevated to cause his symptoms.

It is also possible he may be experiencing a panic attack, but in the presence of his depressed blood sugar (and absence of signs of anxiety), hypoglycemia is the most likely cause of his symptoms.

Abdominal rigidity and decreased bowel sounds are classic signs of peritontis. In addition, the patient will often want to lie very still, as any motion often increases pain. Cystitis, ulcerative colitis, and cholecystitis all may cause significant abdominal tenderness but would not generally result in rigidity or decreased bowel sounds.