Doctors use dozens of tools every day, ranging from simple handheld instruments that have barely changed in over a century to portable ultrasound devices that fit in a coat pocket. The specific tools depend on the setting: a primary care exam room, an operating room, and a specialist’s office each have their own lineup. Here’s a practical look at the instruments you’re most likely to encounter and what each one actually does.
Tools Used in a Standard Checkup
The most familiar medical tools are the ones your doctor pulls out during a routine physical exam. A stethoscope is the most iconic. It has two sides: a flat disc called the diaphragm that picks up high-pitched sounds like breath sounds and certain heart murmurs, and a hollow cup called the bell that captures low-pitched sounds like deeper heart tones. Research has confirmed that the bell side produces a louder output at low frequencies, which is why doctors flip between the two sides during a single exam.
A blood pressure cuff (sphygmomanometer) is another staple. Offices use both manual cuffs, where the doctor listens through a stethoscope while slowly releasing air, and automatic digital monitors that inflate and read pressure electronically. The American Heart Association recommends validated upper-arm cuffs for accuracy, noting that wrist and finger monitors give less reliable readings.
Other standard exam room tools include:
- Thermometer: measures body temperature, now typically with digital or infrared sensors rather than mercury
- Otoscope: a handheld light with a magnifying lens used to look inside the ears
- Ophthalmoscope: shines a focused beam into the eye so the doctor can examine the retina and optic nerve
- Tongue depressor: a flat wooden stick that holds the tongue down to inspect the throat
- Pulse oximeter: a small clip placed on the fingertip that reads blood oxygen levels in seconds
Neurological Exam Instruments
When a doctor needs to check your nervous system, a few specialized tools come out. The reflex hammer is the most recognizable. It’s a small, weighted mallet used to tap tendons at the knee, elbow, and ankle. A brisk kick of the leg after a knee tap tells the doctor that the nerve pathway between the spinal cord and that muscle is intact. Well-weighted models like the Queen’s Square or Babinski hammer give the doctor more control over the tap.
A tuning fork, usually tuned to 128 Hz, tests your ability to feel vibrations. The doctor strikes it and places the base against a bony area like your ankle or wrist. If you can’t sense the buzzing, it may signal nerve damage, which is especially important for people with diabetes. A higher-pitched 256 Hz fork is sometimes used for hearing tests instead. Doctors also use a simple safety pin (discarded after each patient) to check whether you can distinguish sharp from dull sensations on different parts of the body. A small penlight rounds out the neuro toolkit, used to check how your pupils respond to light.
Heart and Lung Monitoring Devices
Beyond the stethoscope, an electrocardiogram (EKG) machine is one of the most important tools in medicine. It uses small adhesive patches placed on the chest, arms, and legs to record the heart’s electrical activity. A standard 12-lead EKG can detect irregular heartbeats (arrhythmias), evidence of a previous heart attack, and signs of blocked or narrowed arteries causing chest pain. The test takes about 10 minutes and produces a paper tracing that doctors read almost instantly.
For lung function, a spirometer measures how much air you can blow out and how fast. You breathe forcefully into a mouthpiece, and the device calculates whether your airways are narrowed, which helps diagnose conditions like asthma or chronic obstructive pulmonary disease.
Portable Ultrasound
One of the biggest shifts in modern medicine is the rise of point-of-care ultrasound (often called POCUS). These are handheld or small mobile devices that let doctors see inside the body at the bedside, without sending you to a radiology department. Early portable models weighed just over three pounds and ran on a two-hour battery. Today’s versions can be even smaller, some connecting directly to a smartphone or tablet.
Multiple studies have found that bedside ultrasound outperforms the stethoscope and standard chest X-rays for diagnosing heart, lung, and abdominal problems. The European Federation of Societies for Ultrasound in Medicine and Biology now recommends incorporating POCUS into routine exams. Doctors use it to check heart function, look for fluid in the lungs, assess abdominal organs, and even estimate bladder volume, all in real time. The trend is moving toward ultrasound partially replacing older techniques like percussion (tapping the chest to listen for dullness) and auscultation (listening with a stethoscope) wherever the technology is available.
Surgical Instruments
Operating rooms contain a much larger and more specialized set of tools. The American College of Surgeons groups them into four main categories.
Cutting instruments start with the scalpel, used for the initial incision. Surgical scissors handle finer cuts and tissue separation. Specialized versions include Pott’s scissors for making precise incisions in blood vessels and battery-powered bone saws. More advanced cutting tools include electrosurgery devices, which use alternating electrical current to cut tissue and seal blood vessels simultaneously, and ultrasonic instruments that use high-frequency sound waves to cut and seal at the same time.
Grasping instruments include forceps (sometimes called pick-ups), which work like tweezers for holding tissue, and clamps, which are locking forceps that can grip tissue firmly or stop bleeding by clamping a blood vessel shut. In minimally invasive surgery, laparoscopic versions of these instruments are long, thin shafts inserted through small incisions, allowing the surgeon to grasp, cut, and cauterize without opening the body widely.
Retractors hold incisions open so the surgeon can see and reach the surgical site. Some are handheld, like the Army-Navy retractor used for skin layers or the Deaver retractor that holds back the abdominal wall. Others are self-retaining, meaning they lock in place and free up the surgical team’s hands. Malleable retractors can be bent to fit the specific shape needed.
Suturing instruments close the wound afterward. Curved needles threaded with suture material are the standard for internal tissues, while straight needles handle skin closure. Suture itself comes in absorbable varieties that dissolve on their own and non-absorbable types that need to be removed later. For some skin closures, surgeons skip sutures entirely and use surgical staplers or medical-grade skin glue instead.
Digital and Software Tools
A significant portion of what doctors “use” today is software. Electronic health records (EHRs) have largely replaced paper charts and serve as the central hub of patient care. An EHR stores your medical history, diagnoses, medications, immunization dates, allergies, radiology images, and lab results in one place. It also gives doctors access to evidence-based decision support tools, essentially built-in references that flag potential drug interactions, suggest diagnoses based on symptoms, or alert the doctor to overdue screenings.
EHR systems also handle electronic prescribing, sending prescriptions directly to a pharmacy, and allow different providers to share your records. If you see a specialist, they can pull up the same chart your primary care doctor uses, reducing repeated tests and miscommunication.
Protective Equipment
Personal protective equipment (PPE) isn’t a diagnostic tool, but it’s something you’ll see doctors use constantly. The FDA requires that all medical PPE meet performance standards ensuring that blood and other infectious materials cannot pass through to the wearer’s skin, eyes, mouth, or clothing under normal conditions. This includes examination gloves (typically nitrile or latex), surgical masks, face shields, and gowns.
For airborne threats, doctors use respirators certified by the National Institute for Occupational Safety and Health (NIOSH). Only respirators that meet the standards outlined in federal regulations can carry the NIOSH-approved label. The N95 respirator, which most people became familiar with during the COVID-19 pandemic, is the most common example in clinical settings.