Related topics

Mind Matters: Vampires, fleas and shrinks

March 25, 2019 GMT

I looked across my desk at the little fellow sitting next to his mother. His eyes widened, his lower lip started to tremble and a single tear made its way down his face. If he could have crawled into her lap and gotten any further away from me, he would have.

“He hates needles,” his mother said, matter-of-factly.

“Mmmmph,” said the little one, clearly mortified now that the thing-that-shall-not-be-named had been named.

“He’s afraid they will take all his blood – like a vampire, you know,” said his mother.

“I do,” I said.

I looked over at my young patient, who was being treated with a drug that was supposed to help him feel less agitated, less hostile and less moody. This drug, like many others we use in mental health, also required ordering periodic blood tests to ensure that it was not also causing untoward effects such as liver damage, endocrine imbalances and awkward physical changes in growing children.

“It’s more like a flea,” I said, leaning in toward my patient conspiratorially. “Just a little pinprick, a little sample, done.” A white lie, this one, but sometimes necessary to move the process along. In actual fact, I hate to have my blood drawn too.

His shoulders lowered a bit, his eyes reverted to their normal size and he slid from his mother’s back into the neighboring chair, not quite believing me yet – but closer.

“Let’s give it a try,” I said, handing mom a blue lab requisition form, with several check marks denoting diagnoses, required tests and contact information.

They rose to leave my office and my patient gave me a wide berth on the way out. I did not look like a vampire, to be sure. I did not even wear the long white coat that makes most kids cry on sight when they enter the doctor’s office. All the same, I still had the power to order the extraction of bodily fluids, and most kids, even most adults, do not take kindly to the process of being poked with a large needle in a small vein.

Why do I, and many other providers, subject you, your kids, your spouse and your parents to such periodic torture? Lab testing is part of that whole process we have discussed before – the process of a complete evaluation of a mental or physical disorder, making a good working diagnosis, crafting a reasonable treatment plan and then following up to see if it works to make the symptoms and the illness better. When you first go to see your provider, you go through a pretty thorough assessment. You provide personal information, get out your insurance cards, fill out paperwork and have your vital signs measured. You answer questions about your general health, your habits and the specific symptoms that brought you in for the visit. Then you see the doctor or PA or NP or whoever your provider might be for that day, and they ask more specific questions, honing in on what the problem is and thinking with you about ways that you might approach diagnosing and treating what ails you. You may have a limited or more extensive physical examination as part of the process. After all that is done, you may be sent to get laboratory testing done, or some of it may be completed right there in the medical office.

Why labs? Lab tests are just a piece of the broader puzzle that is you and your health. They can establish a baseline that gives your provider a snapshot of your health at a point in time, they can monitor progress in treatment and they can herald side effects or other problems that then trigger a change in the treatment plan. Baseline lab testing tends to be more broad and extensive as a rule, as a provider might cast a wide net in order to get a look at the overall picture of your health. More detailed or targeted testing might be done later to monitor drug treatment, assess recovery or track improvement or recurrence in certain diseases.

What are some of the most common lab tests that your provider might ask you to get, and what might they reveal?

A basic metabolic profile, or BMP, gives an idea of how your body’s general metabolic processes are running. Blood glucose determinations, kidney functioning and levels of electrolytes may all be reviewed.

A complete blood count, or CBC, looks at your hemoglobin and hematocrit, red and white blood cells, and platelets and other blood components. Anemia, susceptibility to infection and clotting disorders might be picked up with this test.

Lipid panels help you “know your numbers,” as we now know that better control of good and bad cholesterol, triglycerides and other fats may help to prevent cardiac and vascular problems as we age. We also know that some mental health medications may adversely affect blood sugar, lipid levels and other parameters and need to be monitored routinely.

Thyroid studies (TSH, T4, T3, others) may signal an overactive or underactive thyroid gland, which may indicate a primary health condition or one that is brought on by medication treatment for some other illness.

A urinalysis, coupled with a measurement of creatinine and a UDS (urine drug screen), gives invaluable information about regular kidney function, clearance of toxins and wastes from the body, and the presence of licit or illicit substances in the system. Note that some urine drug screens are done using chain of custody, which may be used by employers and courts.

Lastly, specific blood or urine samples may be requested to get levels of certain therapeutic drugs such as lithium, valproic acid, carbamazepine, antidepressants or antipsychotics. Some of these drugs work best at prescribed levels in the blood stream, and some tend to have fluctuating levels over time and must be titrated for best effects. Some may have narrow therapeutic windows, which means that the distance between a good, therapeutic level in the blood and a toxic, potentially harmful level is not that great and must be watched closely.

The next time your provider orders lab testing, rest assured that he or she does not mean to cause you undue distress or pain but only wants to monitor your care to maximize positive outcomes and prevent side effects, adverse events and unintentional harm.

Meet me back here next time to talk about dementia. Is there more than one kind? How is it diagnosed? Can it be treated?

As always, thanks for reading, and happy spring!