Propofol: Better Sedation, Quicker Recovery
Conscious sedation has been around for years. A decade ago it was benzos and narcotics (usually fentanyl). Several years back low-dose etomidate gained popularity but it suffered from side effects, myoclonus being the most. This made one of the most common ED uses of conscious sedation (fracture and dislocation reduction) difficult if not impossible. Most recently, the safety of etomidate has been questioned due to its association with adrenal insufficiency. Now comes Propofol, a drug commonly used for sedation of OR and intubated ICU patients. Propofol is seeing increased use in conscious sedation at doses of approximately 10-20 mg (always better to start low and titrate) IVP q 20-30 seconds until sedation is achieved. From that point about 0.1 mg/kg/min may be used to keep a patient properly sedated. Caution should be used when bolusing Propofol as a major side effect is hypotension and if boluses are given too rapidly you can stack the dosing and find your patient too sedated. Propofol is an excellent agent for the sedation of mechanically ventilated patients. Doses range from 5 mcg/kg/min to 50mcg/kg/min. Its short half-life and duration of action make it ideal for our environment. No further monitoring is needed 15 minutes after the drug has been discontinued, which can be crucial in a busy ER as you no longer tie up a bed for an extra hour after a sedation.
Digital Radiology and Multirow CT Scans:
When I started this game a little over a decade ago head CTs were common place and abdominal CTs were ordered only if you “really needed” them. Surgeons still took patients to the OR for a suspected appy. A sick trauma got X-rays of their C-spine, chest and pelvis, and you thought about what other imaging might be needed. As CT scanners have multiplied their rows like bacteria on a petri dish, right or wrong, we have exponentially increased their use. Now, any moderate mechanism MVC gets a trauma scan‚ meaning CT head through pelvis. Everyone with chest pain and shortness of breath gets a chest CT, and everyone with abdominal pain, tenderness and a mildly elevated WBC gets a belly CT. As CT scanners have increased their rows, they have increased their speed meaning a pan scan ties up a CT gantry for 5-10 minutes instead of 30. It literally takes longer to set the patient up for the scan than to complete the scan. Along with speed, multirow detectors also offer us the ability to get much finer detail in our images, allowing for much greater detail and a better chance at detecting pathology. Secondly, in medicine we have the growing sense that we cannot afford to be wrong so everyone wants to gather more information. The downside to CT imaging is that it does not come cheap. With every scan comes a significant dose of radiation and those doses add up over time. Think about a woman in her 20s with recurrent renal calculi. How many scans might she receive during her reproductive years? How many over her lifetime? While still not quite ready for prime time, the triple scan is just around the corner. The hope is that with a single scan we rule out aortic dissection, myocardial infarction, and pulmonary embolism in one shot. Keep your eye on MRI, which is exploding in use similar to what CT scans saw a few years ago.
Alternative Vascular Access: Use Your Whole Toolbox
Five years ago when a nurse told you they could not get an IV on a patient with no EJ available, you’d immediately go to a central line. This mentality has slowly been nudged by the wayside with increased use of ultrasound-guided intravenous access and acceptance of intraosseous access as an alternative in adults. An ultrasound quickly finds appropriate targets without discomfort to the patient, and can then help a skilled user visualize cannulation of the vessel in real time. Remember, though, that deeper lines can eject under high flow just like an EJ, as the extra layers of tissue allow for movement of the catheter outward under sustained high flow injections such as those seen with CT scans ( i.e. PE and Dissection studies). If immediate access is what you need then an intraosseous needle is the answer. Vidacare’s EZ-IO is my personal favorite for ease of use, patient comfort, and speed. But other alternatives exist including Cook, Jamishidi, Bone Injection Gun, and FAST-1 Sternal IO. IO can be used for basically any rapid infusion med but will not give you the flow needed for CT scans. Remember that IOs cause mild discomfort during insertion but severe pain with infusions so a little cardiac lidocaine goes a long way.
Fiberoptic Airway: The Light at the End of the Tunnel
There has been a virtual explosion of alternative/difficult airway devices over the past 5-10 years but it is in fiberoptics that we are seeing the most dramatic changes. Fiberoptics give you the benefit of seeing your target from an internal perspective so you do not have to align three different axes in order to visualize an intubation, making anterior and obese airways much easier and making an in-line intubation effortless. They also have the added benefit of letting others see what you see, improving teaching of novices, as well as helping others assist an experienced operator. Fiberoptics come in two basic flavors, those with the camera at the tip at the leading edge of an internal stylet (i.e. Storz Bonfils, Airway RIFL, Levitan, or flexible scopes) and those with a camera built into a laryngoscope-style blade (i.e. GlideScope or Storz devices). Recent generations of devices have improved optics over their predecessors, and Storz recently introduced a high definition line. The latest and greatest devices are starting to tout built-in recording options, which are great for on-the-spot teaching or QI.
Both CPAP (constant pressure delivery through inspiration and expiration) and BiPAP (positive airway pressures at different levels during inspiration and expiration) have been around for some time now but they are seeing increasing usage in the ED and on EMS rigs to stave off intubation. The patients who seem to do the best are those with CHF followed by COPD and those with bilateral pneumonia. Asthma sufferers seem to get the least benefit. Multiple studies cite significant improvements with pre-hospital and emergency department use of CPAP and BiPAP reducing intubations, hospital stays, mortality and the cost of care. I think most of us have seen patients destined to suck on plastic saved from intubation by BiPAP. Like IO access, expect to see more patients coming in by EMS already on CPAP.
The push to get the equivalent of a Swan-Ganz catheter continues with several machines out in the past couple of years all purporting to do it better than the next. Recent literature shows that use of CVP and Sv02 as a guide in sepsis may not be the Holy Grail the Rivers data implied it should be. The fact of the matter is that CVP is a snapshot estimate of preload in a patient and is not applicable to every patient situation. Look for future devices to take continuous measurements in an attempt to overcome this by using variability between the measurements as tools in determining the volume status and cardiac output. These devices come in two flavors: invasive (Edwards Vigileo, CardioQ esophageal Doppler), and non-invasive (USCOM 1A, bmeye NexFin HD, and Cardio Dynamics BioZ). Monitors such as the InSpectra Tissue Oxygenation Monitor use tissue perfusion as another tool in your kit with some early abstracts pointing towards variability of StO2 (soft tissue oxygen) recovery as a reliable measure of microcirculatory function.
Personal Digital Assistants:
I consider myself a younger doctor having been in medicine since the late 90s, but I can recall the days of med students and residents carrying pounds of books in their pockets to the point that pockets were bulging at the seams and would occasionally tear out. We affectionately referred to this as the pocket lavage. I bought my first PDA in 1998 and was one of a handful of students using one. Residents and attendings would look with great interest at what I could do with this small device in the palm of my hand. What a change a decade makes. Physicians have adopted PDAs much more rapidly than the general population with younger doctors, residents and students leading the pack. The always-resistant surgeons have been the slowest to adopt PDAs. A few years back, Research In Motion (RIM) took the PDA scene by storm with the Blackberry line, which combined a PDA and phone into one slick package. Between Blackberry and Windows mobile, the original PDA King Palm was barely eking out an existence. Everything changed with the introduction of the iPhone, now in its third iteration with the 3Gs. The iPhone really brought the PDA to the masses and changed the landscape of PDAs forever. Palm has answered with the Palm Pre‚ which was met with mixed reviews. All of these devices offer you every pocket book you could want with PEPID being the most useful and concise for use in the ED. But it’s the extras that make the difference and at this moment in time no one offers more apps (many for free) than the Apple iPhone. My iPhone currently has apps (application) for ABG analysis, RSI (great for Peds or dosing for unusual cases), eye charts, med calculators, OB wheels, blood alcohol, PEPID, Epocrates, as well as multiple apps to fill little dead spots in the day and to help organize your life. Thanks to my PDA I can carry all of the info I need on my hip and leave my lab coat, which I’ve always hated anyway, to collect dust in my closet. Look for PDAs to start to link into hospital systems in the future for real-time viewing of vital signs and test results (see Airstriptech.com for the iPhone).
You’ve heard it before, but medicine is definitely making the transition from an analog world to a digital one. We see the transition in the way we communicate, moving from overhead pages (“Dr. Strangelove to room 13 STAT!”) to personal communication devices. These new devices range from Voice Over Internet Protocol (VOIP) phones to wearable Star Trek-like communicators. The PolycomSpectraLink series is an example of the former, while the Vocera B2000 Communications Badge is an example of the latter. Having the ability to call consultants and staff for help, as well as receive calls anywhere in the ED no matter what you are doing (even when using the rest room) is a great boon in a busy department. Many of us are also seeing the loss of the analog pen in exchange for the keyboard and digital pen. Physician documentation software has also exploded over the past few years. The T-System, which started with a digital version of their popular charting software, has now expanded to a complete ED patient tracking package. HMED software attacked the same problem from the other direction starting as a patient tracking system that expanded into documentation. One of the great benefits of these systems is the ability to log into any computer in the ED (sometimes finding an open computer can the hardest part) and access patient records for lab/radiology results, order entry and documentation. This can be very helpful when you are stuck in a sick patient’s room but still need to check on your other patients. Online, you can access virtually every textbook in medicine, as well as every article written in every journal for the past few decades. If your system subscribes to these resources you literally have the world of accumulated medical knowledge at your fingertips. The virtual expansion is also connecting facilities with virtual critical care bays and ICUs, allowing doctors and nurses at larger hospitals to assist with complicated cases in smaller facilities.
MedGadget.com’s favorite gear
The Portable CO-Oximeter:
Unsung Triage Workhorse
by Nicholas Genes, MD
When thinking of cool new gadgets we use in the emergency department, docs invariably mention expensive devices with sexy screens and fiber optics. These gadgets are glamorous. Not only do they help in high-profile situations where older technologies may not be sufficient, but bringing out this tech attracts a crowd of fellow docs, students, nurses, family and other patients – and when used successfully, these devices have been known to spur spontaneous high-fives among operators and onlookers.
But today we put the spotlight on a decidedly less glamorous device. It lacks a colorful video screen and It’s not reserved for the tough cases but rather used as a workhorse at triage, on patients that most of us would say aren’t that sick. This gadget doesn’t change the course of patient care very often – but when it does, it can be dramatic.
I’m talking about the non-invasive, portable CO-oximeter. These little devices work just as easily as your standard pulse oximeter – they’re about as small, and can be used on patient after patient – but in addition to oxygen, they can detect carboxyhemoglobin (some models also can identify methemoglobin). Their reported values of COHb correlate very well with serum levels over a wide range, and with remarkable accuracy. Since it’s impractical to send blood tests for carboxyhemoglobin levels on everyone presenting with flu-like symptoms, this gadget quickly gives docs data on important and probably under-diagnosed toxicity.
A recent trial looked at all non-critical adult patients who presented to a large academic ED (Suner, 2008). From this group they found 28 cases of carbon monoxide toxicity – 11 of which were completely unexpected. That may not sound like a lot when you consider they screened over 14,000 patients (and there were a few false positives, too). But when you think about all the patients we see in the ED with vague complaints of headache, fatigue or nausea, well, wouldn’t you want this little piece of information before sending these folks back into a potentially unsafe environment? The authors have picked up many cases of occult CO toxicity over the years, and, when the fire department surveyed these patients’ homes, they found dangerous heating conditions or faulty venting.
We remind ourselves to check for CO poisoning in the winter, or after natural disasters when patients are using alternative forms of power. But we still end up missing many cases of CO toxicity, and indeed, many facilities lack the ability to test for it at all (Hampson 2006). The CO-oximeter is an easy-to-use tool that may influence the course of care for a small but vulnerable population – at that’s why we’ve chosen it as Unsung EM Gadget of the Year.
(Disclosure – in the study cited, the CO-oximeter manufacturer, Masimo, supplied materials and funding for research assistants, and one of the study authors is an EPM advisor.)