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The Procedural Pause by James R. Roberts, MD,
& Martha Roberts, ACNP, PNP​

​Renowned emergency physician James R. Roberts, MD, and his daughter, Martha Roberts, ACNP, PNP, are the team behind The Procedural Pause.

The blog will focus on procedures that emergency physicians, residents, and midlevel providers are often called on to perform in the ED. Each case will cover the basics, the best approach for treatment, and pearls and pitfalls.

This blog conveys personal opinions and experiences, and application of the information here remains the professional responsibility of the clinician. Tthis blog is not intended to dictate standard of care, but is a clinical guide, not a legal document. Do not reference this site in court or as a defense. It is your responsibility to follow your hospital’s procedures and protocol and to practice under the guidelines of your professional license.

Please share your thoughts about the Roberts' posts.

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Saturday, June 1, 2019

Dozens of pharmaceutical commercials about dry eyes play on television or the radio. Ophthalmologists often use punctal plugs, also called lacrimal duct plugs, for this diagnosis.

Punctal plugs are tiny devices that fit snugly in the tear ducts or puncta of the eye. The plug completely blocks the duct and prevents tears from draining. This allows the moisture in the eye to stick around longer and lubricate the eyes. Patients rarely have major complications from the plugs, but they can fall out or slip out of position.

Patients with dry eyes may have chronic aqueous tear deficiencies or have other ocular issues such as keratoconjunctivitis, keratitis, or recurrent corneal erosions. They may try artificial tears, but these can be cumbersome and expensive. Studies have suggested using the plugs as a simple and effective alternative for dry eyes. (Cornea. 2002;21[2]:135; http://bit.ly/2DuuCo5; Am J Ophthalmol. 2001;131[1]:30; http://bit.ly/2XBM5m0.)

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A punctal plug.

Three types of plugs are available—collagen, silicone, and intracanalicular—and it's important to know their basic differences. All are placed by an ophthalmologist, and the lacrimal ducts occasionally need to be dilated during placement. Sometimes, the plugs fall out or loosen. Collagen plugs dissolve over time, and silicone and intracanalicular plugs last longer. Patients usually have silicone plugs, which look like flat white discs sticking out of the lacrimal duct; intracanalicular plugs extend into the duct and cannot be seen on the surface.

Extreme tearing, canaliculitis, and dacryocystitis are associated with these plugs. They can also migrate proximally into the lacrimal ducts. If the plugs become painful, irritated, or infected, an ophthalmologist may need to remove them surgically. (Ophthalmic Plast Reconstr Surg. 2001;17[6]:465; http://bit.ly/2UXbeLe.)

When a patient presents to the ED with visible punctal plugs, he may be experiencing irritation and ask you to remove them. Check the position of the plugs, and then call the ophthalmologist to discuss if possible. He may suggest attempting to push the plug back in place, which is easily done with a cotton swab and some patience. Do your best to keep the plugs in place unless they are causing severe side effects.

Minor symptoms and foreign-body sensation is normal for the first 24 hours after insertion. The lacrimal ducts can be sensitive from dilation and may need lubricating drops or 12-24 hours of ocular numbing drops. Patients may complain of mild ocular pruritis and burning, mild to moderately red conjunctiva, and foreign body sensation. Excessive tearing with punctal plugs is normal and expected. Reassure the patient that this will pass.

 PP-reposition punctal plug.jpg

Watch this attempt to reposition a punctal plug.

It's important for physicians to be able to detect plug loss and reposition plugs if indicated. Next month, we will review common side effects and show you how to extract them.

Wednesday, May 1, 2019

Bedside ultrasound can be useful for identifying lung structures and assisting with chest tube placement. It can also be used to identify a pneumothorax and confirm chest tube placement post-procedure. Practice looking for signs, and make sure you can identify them in normal pediatric and adult patients. You may still need additional imaging such as chest x-ray and CT to confirm the diagnosis, but US yields immediate and accurate results.

Check first for lung sliding, a simple yet convincing finding on US confirming that the lung is inflated. A thin, white line will be seen, which highlights the lung's pleural lining. It may appear shiny or shimmery, and will move back and forth subtly as the patient breathes. Monitor this for a few breath cycles to confirm. The absence of this feature indicates a pneumothorax. You may also see a comet tail, a special form of reverberation artifact.

PP lung sliding.jpg

Lung sliding and comet tail artifact identification are valuable US skills. Dulchavsky, et. al., performed a prospective evaluation of the sensitivity and specificity of thoracic US in detecting pneumothorax by looking for lung sliding and comet tail artifacts against chest x-ray. A total of 382 trauma patients were examined, and US confirmed 37 of 39 pneumothoraces. (J Trauma. 2001;50[2]:201.) This was 95% sensitive. CXR was completed after US and also confirmed all pneumothoraces.

The authors noted that two pneumothoraces were missed on US because subcutaneous air did not allow visualization of lung sliding. The true-negative rate was 100%. The authors also concluded that a FAST exam should include the thorax to facilitate early and accurate diagnosis of pneumothorax. This could assist with timely procedures, consultation, transfer, and treatment.

Studies have also shown that US may decrease the need for CT in diagnosing pneumothorax. A retrospective study by Lichenstein, et al., examined how chest x-ray can miss pneumothorax, suggesting that CT may be indicated to confirm the diagnosis. (Crit Care Med. 2005;33[6]:1231.) They hypothesized, however, that US may be an alternative method to diagnose pneumothorax. Pneumothorax was diagnosed if lung sliding could not be seen. Further testing with CT was completed to confirm the diagnosis. The absence of lung sliding was 100% sensitive and 78% specific for pneumothorax. (Crit Care Med 2005;33[6]:1231.)

US, CXR, and CT

CXR and computed tomography have been the gold standard for diagnosing pneumothorax. The literature suggests, however, that bedside US may be superior. A study by Wilkerson and Stone examined 606 trauma patients and found that lung US was 86-98% sensitive and  97-100% specific, while CXR was only 28-75% sensitive and 100% specific. (Acad Emerg Med 2010;17[1]:11; http://bit.ly/2JFFgxv.)

Only blunt trauma patients were included and the study was not randomized, but US was still noted to be far superior to traditional CXR for detecting pneumothorax. US, however, may not be useful in other patients depending on presentation and history. US may miss other traumatic injuries that could be seen on CXR and CT, which remain the gold standard for pneumothorax and other lung abnormalities.

The Approach

  • Use bedside US to examine the lungs and pleural and chest wall structures.
  • Evaluate for pneumothorax or other abnormalities.
  • Use bedside US for diagnosing pneumothorax and chest tube insertion and confirmation.
  • Continue to use CXR or even CT to confirm diagnosis and placement or additional concerning diagnoses, especially in trauma cases.

The Procedure

  • Position the patient at a 45- to 90-degree angle. Supine position may be more difficult when identifying structures.
  • A high-frequency linear probe should be used to look for pneumothorax. The indicator marker should point cephalad, but it is important to be between the rib spaces.
  • Position the linear probe at the midclavicular line, second intercostal space.
  • Examine the unaffected side first, and find lung sliding on ultrasound.
  • Always examine this upper anterior portion of the chest. Air in the pneumothorax will rise to the top of the chest, causing the lung to sink downward into the lung cavity.
  • Examine the affected side and compare it with the unaffected side.
  • Lung sliding will appear bright and white. Subtle movement of this line will be observed.

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Watch a video demonstrating lung sliding using US.

The Cautions

  • Be sure to practice on as many people as possible so you have a firm grasp of what's normal before applying it to patients.
  • Do not hang your hat on the solitary diagnosis of pneumothorax in blunt chest wall trauma. Obtain a CXR or proceed with CT scanning to rule out other life-threatening issues.

Monday, April 1, 2019

Seventy-five percent of trauma injuries involve some kind of thoracic insult, a quarter of which need a procedural intervention like a chest tube. (Surg Clin North Am 2007;87[1]:95; http://bit.ly/2HaoX90.) Long-term illness, lung disease, and post-operative complications may cause pleural effusions or a pneumothorax, so treating these conditions quickly can significantly decrease patient morbidity and mortality. 

Other indications for chest tube placement include:

  • Trauma: Pneumothorax, hemopneumothorax, or tension pneumothorax
  • Long-term illness: Pleural effusion (cancer, pneumonia)
  • Infection: Empyema, purulent pleuritis
  • Post-surgery, especially after lung, heart, or esophageal surgery
  • Bronchoscopy

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A CT showing a chest tube in the right lung and pneumothorax in the left lung from trauma. Scan courtesy of Clinical Cases.

Inserting a chest tube is literally hit or miss. If you miss, you may seriously compromise the outcome, so you need to embrace a few simple concepts: know your landmarks, know your technique and tools, and know the cautions and what can go wrong.

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This 49-year-old morbidly obese woman had a spontaneous pneumothorax four days after elective bronchoscopy. Note the misplaced pigtail catheter in the subcutaneous tissue to the left of the fifth intercostal space on the right side of the patient's rib cage. The standard approach was used for this insertion without success.

The Basics

Chest tube insertion should be well-rehearsed and instinctive. You should not hesitate to insert a life-saving tube into a pleural cavity immediately to drain air, blood, bile, or pus. Obtaining a thorough history and chest x-ray is absolutely pivotal to your diagnosis. Know your landmarks before insertion: the fourth and fifth intercostal space and the anterior-axial line. Go up and over the rib as you insert chest tubes. Avoid the lower rib margin to prevent injury to the neurovascular bundle.

You can use one of several tube thoracostomy techniques. Most clinicians prefer standard or classic insertion, that is, blunt dissection (incision, Kelly clamp, finger placement, tube placement). Others may prefer the Seldinger technique using pigtails, but these are usually reserved for pneumothorax only. Pigtails can be placed anteriorly or laterally. It may be difficult to place them laterally in obese patients.

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Use ultrasound to identify landmarks. Find the space between the fourth and fifth ribs. Chest wall anatomy should be confirmed before placement to minimize complications. Use a pen to draw out the safe zone to assist with placement. Photo by Martha Roberts.

Insertion Devices and Techniques

  • Classic approach, blunt dissection
  • Seldinger approach, pigtail insertion
  • Trocar insertion
  • Handheld insertion device such as the Reactor
  • Needle thoracostomy

The Trocar

An alternative method utilizes blunt or sharp trocar insertion. These devices are metal or plastic obturators with a sharpened or blunt tip and a hollow tube. The trocar method requires first making an incision in the same place as for the classic technique. A Kelly clamp may or may not be used. The trocar is blindly advanced to the pleura and then forced through the pleura into the chest cavity. The obturator is removed, and the chest tube remains in place. But is it safe to use a trocar chest tube?

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Sharp trocar tips and trocar storage tubes. Photos by Martha Roberts.

Medscape notes that targeted guidewire (pigtail) and trocar-guided placement are considered high risk for complications in the ED, and that the standard or classic technique should be used for emergent thoracostomy. ("Tube Thoracostomy." Nov. 16, 2018; http://bit.ly/2EiYfZ2.) One study noted that even experienced respiratory physicians and thoracic surgeons may overpenetrate the trocar and cause visceral injuries. (Thorax 2010;65[1]:5.)

Trocar insertion techniques may be valuable if there is extensive chest trauma or multiple broken ribs and a risk to the provider entering the chest cavity with an unprotected finger. Trocars may also be useful in morbidly obese patients or in rural settings with limited resources.

 PP trocar 5.jpg

Have your setup with Pleur-evac and suction ready to go before becoming sterile or making an incision. Photo by Martha Roberts.

Trocar Safety

Four of seven reports in a meta-analysis of trocar insertion safety concluded that the technique was associated with a significantly higher rate of tube malposition and complications. (Interact Cardiovasc Thorac Surg 2014;19[1]:125; http://bit.ly/2Sv5F0b.) One of the retrospective reviews in the analysis found the rate of tube malposition to be similar in groups using the trocar and blunt dissection. The authors, however, abandoned the trocar technique because of severe complications like lung and stomach injuries. Other studies in this meta-analysis showed that the trocar was "as safe as and even more effective than blunt dissection alone." A randomized prospective study in cadavers also included in the meta-analysis found fewer complications with blunt tip trocars than sharp ones.

The authors advised avoiding the blind trocar technique for chest tube placement in adults because of the higher incidence of malposition and complications. They recommended using the blunt dissection technique with digital exploration of the pleural cavity before chest tube placement. One of the studies, however, found that blunt dissection into the pleural space, followed by the use of a trocar to direct the chest tube, was as safe as and more effective than blunt dissection alone. (J Cardiothorac Surg 2010;5:21; http://bit.ly/2BPtzOD.)

The type of trocar you choose is also important. A Scandinavian study in 100 human cadavers found misplacements and organ injuries occurred more frequently using sharp-tipped trocars than blunt ones. Success rates were 92 percent using blunt tips v. 86 percent using sharp-tipped trocars. Neither type of trocar showed a significant decrease in time to complete the procedure. (Scand J Trauma Resusc Emerg Med 2012;20:10; http://bit.ly/2IFXgHO.)

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Watch this informal but informative discussion about trocar insertion with C. Trey Dobson, MD, and Dedrick Luikens, DO.

Pearls

  • The British Thoracic Society released well-researched guidelines in 2010 about chest tube emergencies and insertion skills. (Thorax 2010;65[Suppl 2]; http://bit.ly/2Ua2wET.)
  • The society recommends performing erect, posteroanterior inspiratory chest x-rays for suspected pleural effusion and to confirm tube placement. If identification is difficult, increase specificity by adding supine or lateral decubitus x-rays, ultrasound, and finally CT (in that order) to aid in diagnosis. Ultrasound is an emerging technology for assessing tube placement, but chest x-ray is standard of care. (Medscape. "Tube Thoracostomy." Nov. 16, 2018; http://bit.ly/2IGtiU9.)
  • Ultrasound does, however, detect pleural fluid septations with greater sensitivity than CT, and it can be useful during procedures to reduce the risk of organ puncture, according to the British Thoracic Society guidelines.
  • Keep in mind the potential toxicity of lidocaine for localized injection. The maximum dose is 4-7 mg/kg (0.4 to 0.7 mL/kg), depending on whether epinephrine is used. (UpToDate, "Subcutaneous Infiltration of Local Anesthetics," April 3, 2019; http://bit.ly/2H8AeH1.)
  • Consider less common causes of pleural exudates such as tuberculosis, pulmonary embolism, autoimmune disorders, asbestos, pancreatitis, sarcoidosis, lymphoma, post-MI, and post-CABG. Yellow nail syndrome, drugs, and fungal infection can rarely cause this condition.
  • Malignant effusions can be diagnosed by pleural fluid cytology in about 60 percent of cases, but MRI and PET are the most effective, according to the British Thoracic Society guidelines.
  • Give prophylactic antibiotics when chest tubes are placed in trauma patients, particularly in those with penetrating injury. A meta-analysis of five trials found antibiotics significantly decreased the risk of empyema in patients with blunt or penetrating thoracic trauma compared with placebo. (UpToDate, "Placement and management of thoracostomy tubes and catheters in adults and children," Feb. 19, 2019; http://bit.ly/2GNrHdo.)
  • All kinds of things can go wrong. Read about them in the International Journal of Critical Illness & Injury Science (2014;4[2]:143): http://bit.ly/2T3i1BP.

Friday, March 1, 2019

​Immediate relocation of ankle dislocations is necessary to preserve the vascular or neurological integrity of the lower extremity and relieve extreme pain. Literature reviews reveal that early reduction followed by a short period of immobilization (six to 12 weeks) and functional or physical rehabilitation produce good clinical outcomes. (Injury 2017;48[10]:2027).

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Left ankle dislocation from a football accident. Photo by M. Roberts.

Ankle dislocations occur from blunt or traumatic incidents such as sporting events (football, gymnastics), motor vehicle crashes, falling, or jumping. Patients may state that their toes were pointed down or plantar-flexed during the impact or that their ankles were already turned far inward or outward. (Surg Clin North Am 1965;45[1]:79.) Significant force is required to produce an ankle dislocation.

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An x-ray of an ankle joint in the AP view showing fracture-dislocation of the ankle. Source: Creative Commons.

At-Risk Populations

  • Sporting accidents (31%) and motor vehicle crashes (30%) are the most common causes of acute ankle dislocation. (Injury 2017;48[10]:2027.)
  • These injuries usually happen to men and boys.
  • Obese patients and those who smoke are at higher risk. (Bone Joint Res 2013;2[6]:102; http://bit.ly/2DGG94d.)
  • Prior history of ankle fracture, strains, or sprains increases risk.

Ankle Anatomy Review

  • Three bones make up the ankle joint: the tibia, fibula, and talus. Below the ankle joint is the subtalar joint, which is between the talus and the calcaneus.
  • Ankle dislocations tear multiple ligaments and the joint can be unstable, including the deltoid and calcaneonavicular ligament (spring ligament), the anterior talofibular ligament (ATFL), the posterior talofibular ligament (PTFL), and the syndesmosis (includes AITFL, PITFL, TTFL, IOL, ITL).
  • Types of dislocations are anterior, posterior, medial, lateral, superior, or combined.
  • Posterior dislocations (46% of the time) are most common. (Injury 2017;48[10]:2027.) The talus bone is often pushed behind the other ankle bones. Dislocations may also be pushed to either side, to the front, or upward. Disruption of the mortise is variable. (Foot Ankle 1988;9[2]:64.)
  • Ankle dislocation without a fracture is a rare diagnosis. (Clin Orthop Relat Res 2001;[382]:179.) It's more likely to have a fracture-dislocation than a sprain or tear dislocation alone.
  • Neurovascular compromise is also rare, although possible.

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AP image of a normal left ankle in an adult (left). Lateral drawing of the left ankle (right). Source: Creative Commons.

Types of Ankle Dislocations

  • Posterior dislocation: The talus moves backward in relation to the tibia (plantar flexion during the injury).
  • Anterior dislocation: The talus is pushed forward in relation to the tibia (dorsiflexion during the injury).
  • Lateral dislocation: The ankle is twisted from inversion or eversion with associated malleolar fractures.
  • Superior dislocation (pilon injury): The talus is pushed upward in the space between the tibia and the fibula, typically from axial loading such as jumping, falling from a height, or having a foot on the brake pedal in a motor vehicle crash.


Complicated bimalleolar fracture of the ankle and questionable dislocation. Consider CT after reduction of the ankle in such cases.

What to Do?

  • Give intravenous pain medication (opioids are a good choice) and immediate procedural sedation if necessary.
  • Obtain x-ray imaging in the AP, lateral, mortise, and oblique views. The mortise and oblique views are taken with an internal rotation of 10-20 degrees, placing the medial and lateral malleoli in the same horizontal plane, which provides optimum viewing of the tibial plafond and talar dome. (Medscape. April 28, 2016; http://bit.ly/2UljqQk.)
  • Perform closed reduction of the joint and stabilize.
  • Repair any laceration. Larger lacerations or open fractures most likely need immediate orthopedic surgical repair.
  • Obtain bedside fluoroscopy or post-reduction films. Check out our November 2015 blog post on fluoroscopy for a refresher! (http://bit.ly/2Gd5FiP.)
  • Splint immediately at 90 degrees at the ankle. Use short posterior leg splint with short stirrup reinforcement for dislocation without significant fractures and long posterior leg splint with short stirrup reinforcement for fracture-dislocations.
  • Use elevation and ice, and give more pain control. (Roberts and Hedges' Procedures in Emergency Medicine and Acute Care, 7th Edition. Philadelphia: Elsevier; 2017.)

PP-ankle dislocation3.jpg

Short or long posterior splint with important stirrup reinforcement to keep the joint stable. Have all supplies ready to go before you start the procedure. The use of multiple bandages is suggested. This is a two-person job. Watch a video of how this is done.

Long-Term Complications

  • Chronic pain, stiffness, and immobility
  • Infection. Open fractures need antibiotics. (J Trauma Acute Care Surg 2014;77[3]:400.)
  • Nonunion of the bone, or avascular necrosis
  • Multiple surgeries, pins, plates, or other
  • Vascular or nerve damage
  • DVT
  • Use caution for patients with diabetes and peripheral vascular disease, smokers, obesity, advanced age, and pediatric growth plates.

Discharge vs. Surgery

Discharging closed ankle dislocations is acceptable in the emergency department as long as patients have no neurovascular compromise, open fracture, or other orthopedic complications. Acute surgical ankles with open fractures need immediate orthopedic consult washout, repair, and possible pinning or plating, depending on the extent of the injury. Many closed dislocations without fracture can be splinted by EPs with urgent follow-up. This scenario is unusual. Expert consult before discharge is strongly advised. An orthopedic specialist should be involved in all ankle dislocations during the ED visit, closed or open.

Next Appointment: Schedule patients with closed, stable relocations to be seen urgently by orthopedics within five days. Give enough pain control for these injuries to last them until their appointment.

Antibiotics: A Surgical Infection Society guideline recommends that open fractures receive intravenous antibiotics and IM tetanus prophylaxis. Data support a short course of first-generation cephalosporins as soon as possible after injury to lower the risk of infection. (Surg Infect [Larchmt] 2006;7[4]:379.)

Hematoma Block? This may be used as an alternative to conscious sedation. It offers a comparable amount of analgesia without the cardiovascular risk, cost, and time. (J Foot Ankle Surg 2011;50[4]:507.)

Malleolar Fractures: Bimalleolar and trimalleolar fractures are unstable and require operative fixation.

Splinting: Patients should be splinted with the ankle joint at 90 degrees, not bear weight, and be referred to an orthopedist within a few days. (UpToDate. June 8, 2018; http://bit.ly/2UnJElp.)

Rehab: Research about early weight-bearing and physical therapy is ongoing. Rehabilitation for most ankle fractures can be carried out with a basic home exercise program of stretching, range of motion, strengthening, and balance exercises. (JAMA 2015;314[13]:1376; http://bit.ly/2UosAM8.)

Friday, February 1, 2019

​The slit lamp is a straightforward and user-friendly machine designed to make ocular exams easy. All the buttons, knobs, and lights, however, can be intimidating. This should not dissuade practitioners from getting cozy, driving the joystick, and evaluating ocular issues.


An ED slit lamp with an LED light and magnification power up to 40x. Photo by M. Roberts.

ED slit lamps are designed to be a bit more basic in function than those found in an ophthalmologist's office. Many EDs may house more complex machinery, but the vast majority of microscope and light arm combination is set at one length with one lens and one to two magnification options. Machines may be equipped with several filters (blue, red-free, green, gray), but cobalt blue is really the only one you need to rule out corneal abrasions. More basic versions of slit lamps in the ED still allow for full corneal and retinal exams.

Consider a few things before performing a slit lamp ocular exam:

  • Evaluate the space and lighting in the room. You should be able to darken the room, and make sure you have enough room; the machine often takes up a lot of space next to a stretcher.
  • Check the machine and set up. Test the machine to ensure it turns on, and obtain a wheeled stool for yourself and a chair for the patient.
  • Consider the ability of the patient to participate in the exam. Check the patient's ocular pressure using a tonometry pen before completing a slit lamp exam. See our November 2018 blog post for more tips on how to complete a tonometry exam.
  • Prepare other equipment: tetracaine or proparacaine for ocular anesthesia; tissues or gauze for the patient to blot her eyes; fluorescein dye to visualize corneal abrasions; pH paper if there is concern for acid or alkaline burns; cotton swabs for lid eversion in the case of foreign body; an 18 g needle for deep foreign bodies; a corneal burr for rust ring removal; and normal saline in 10 mL syringes for quick ocular washout.

The most important part about mastering the slit lamp exam is to have everything you need prior to having the patient put her face in the chin rest. Set up the machine for your comfort before examining the patient. This includes setting the focal length of the lens, adjusting the height and width of the slit lamp beam or light, and positioning the overall table.

Watch our video to see how to successfully set up a slit lamp machine for an exam in less than five minutes.

Troubleshooting issues with the machine:

  • Is it plugged in?
  • Is it turned on?
  • Is the bulb blown?
  • Is the beam horizontal or vertical?
  • Is the width a slit or a circle?
  • Is the intensity too bright or dull?

Jim Weighs In

  • It's important to have the patient keep his forehead close to the strap so his eye does not go out of focus.
  • Clean the chin strap and forehead bar with alcohol prep before positioning the patient.

Martha Weighs In

  • Wash your hands, and wear gloves for ocular exams.
  • Use the joystick at the base of the slit lamp to fine-tune your image.
  • Most manufacturers suggest waiting a full two to three minutes after turning on the light to reach maximum intensity and illumination.

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The round silver knob, left, is used to adjust the slit length, slit rotation, cobalt blue filter, and fixation star control. The smaller lever above it changes other filters (i.e., red-free, green). The illumination head with an LED bulb, right. Photos by M. Roberts.

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Eyepieces and diopters should be initially set to zero, left. The joystick, right, is for fine-tuning and precise movements during the examination. Photos by M. Roberts. 


This diagram shows what the buttons do and where to locate certain features of the slit lamp.