P-video: Remembering NEXUS criteria

Accuracy
Valid for practice
True to literature
Overall quality

Please peer-review this blog post by clicking on the stars above.

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PV card on Cervical Spine Rules:

Canadian C-spine Rules (CCR)

References

1. Hoffman JR, Wolfson AB, Todd K, Mower WR. Selective cervical spine radiography in blunt trauma: methodology of the National Emergency X-Radiography Utilization Study (NEXUS). Ann Emerg Med. 1998 Oct;32(4):461-9. PubMed PMID: 9774931.
2. Hoffman JR, Mower WR, Wolfson AB, Todd KH, Zucker MI. Validity of a set of clinical criteria to rule out injury to the cervical spine in patients with blunt trauma. National Emergency X-Radiography Utilization Study Group. N Engl J Med. 2000 Jul 13;343(2):94-9. Erratum in: N Engl J Med 2001 Feb 8;344(6):464. PubMed PMID: 10891516.
3. Stiell IG, Clement CM, McKnight RD, Brison R, Schull MJ, Rowe BH, Worthington JR, Eisenhauer MA, Cass D, Greenberg G, MacPhail I, Dreyer J, Lee JS, Bandiera G, Reardon M, Holroyd B, Lesiuk H, Wells GA. The Canadian C-spine rule versus the NEXUS low-risk criteria in patients with trauma. N Engl J Med. 2003 Dec 25;349(26):2510-8. PubMed PMID: 14695411.

If you are interested, you can view the results of the Peer Review Demographics data.

Trick of the Trade: Reducing the metacarpal fracture

Metacarpal neck fracture reduction 

General principles of fracture reduction involve axially distracting or pulling on a fracture fragment and pushing the piece back into anatomical alignment. This can be seen in the video above (automatically starts at 2:25 for the actual procedure). What if this approach doesn't work? The fracture fragment remains immobile despite your best efforts.

Image from AO Foundation

Trick of the Trade:
Jahss reduction technique

This technique, also known as the 90-90 approach, involves flexing the patient's MCP and PIP 90 degrees. Dorsal force is applied to metacarpal head by through dorsal pressure on the proximal phalanx. The 90-90 positioning also stretches the collateral ligaments of the MCP joint, which further optimizes the reduction technique.

Although this cool animation below was intended for patient education, it nicely illustrates how the Jahss technique works.

See the Paucis Verbis card on Metacarpal Fractures.

Paucis Verbis: Composition of intravenous fluids

There has been a lot of discussion on the ideal intravenous fluid (IVF) for resuscitation in the Emergency Department and ICU. This was highlighted by the landmark study in JAMA on ICU patients who received chloride-rich versus chloride-restricted IVFs.

This got me to thinking, what exactly comprises the common IVFs that we order? We so often take for granted what's in 1 liter of normal saline. As it turns out, normal saline is not really "normal". Dr. Scott Weingart has a great podcast on "chloride poisoning" using IVFs.

This PV card helps remind me what's in each liter bag of fluids we order. At the bottom half of the card is a brief summary of the JAMA findings.

Feel free to download this card and print on a 4'' x 6'' index card.

[MS Word] [PDF]

See other Paucis Verbis cards.

Update 1/4/13: After the posting of this PV card, there was intense discussion about why the D5W osmolarity was 252 mOsm/L instead of 272 mOsm/L, which is found on various medical calculators. See the discussion by Dr. Joel Topf.

@kidney_boy @m_lin @brianjl @pharmertoxguy Great story.It's not what we know/don't know, it's what we don't know that we don't know.
— David Y.T. Chen (@dytcmd) January 4, 2013

Has this JAMA study and ongoing discussions of fluid content changed your approach to ED fluid management? 

It sure has for me. After 2 liters of normal saline, I consider switching patients to a more chloride-restrictive fluid (we have Plasma-Lyte in our ED). Examples include patients with DKA, AKA, sepsis, and severe dehydration.

Reference
Yunos NM, Bellomo R, Hegarty C, Story D, Ho L, Bailey M. Association between a chloride-liberal vs chloride-restrictive intravenous fluid administration strategy and kidney injury in critically ill adults. JAMA. 2012 Oct 17;308(15):1566-72. PubMed PMID: 23073953. .



Results thus far:

Poll: How would manage a metacarpal fracture in the ED?

I am in the process of creating a PV card on metacarpal fractures, divided into anatomical areas (base, shaft, neck, head), and am realizing that the EM and orthopedic literature don't quite agree. Actually they are quite vague on whether reductions should occur in the ED vs orthopedics clinic in the next few days.

• Do you need to close-reduce all angulated fractures in the ED, which are outside of "acceptable" angulations?
• What exactly are "acceptable" angulations? Some sources say that angulations of 10, 20, 30, and 40 degrees are acceptable for MC neck fractures and only 10, 10, 20, and 20 degrees are acceptable for MC shaft fractures. These numbers, though, vary from reference to reference.

The only consistent thing I've read is that rotational angulation (where not all the fingers point to the patient's scaphoid bone) requires reduction in the ED because of the concern for functional impairment.

School of thought #1:
Reduce all angulated fractures. Heck, it's bent. Straighten it.

School of thought #2: 
Leave all fractures alone. As many of 50% of fractures, especially unstable ones, will lose their realigned position when the patient is seen at the outpatient orthopedic visit. Just splint it and follow-up.

School of thought #3: 
I reduce some but not all angulated fractures.

Would love to hear the variations in people's practice. Feel free to use the Comments section of the blog to explain.

PV card: PE Severity Index (PESI) score

Do you send some of your low-risk patients with pulmonary embolism home?

This is a controversial issue which warrants a look at risk stratification tools. The primary one used is the validated Pulmonary Embolism Severity Index (PESI) score. In Lancet 2011, the authors looked at whether PESI class I and II (low risk) patients could be managed safely as outpatients. It turns out in their study, regardless of whether their PESI class I and II patients were treated as outpatients and inpatients, all fared equally well from a complications standpoint (recurrent clot, bleeding from anticoagulation).

I like the validated PESI scoring system to risk-stratify patients as low vs high risk for complications. I, however, do caution people to look closely at the exclusion criteria for this study before applying this to all ED patients.

The exclusion filter was so strict that they likely have captured a very narrow and unrealistic scope of patients to be widely applicable. It makes sense from a research standpoint to have these criteria to achieve internal validity but the question is external validity. Two exclusion criteria that struck me as awfully strict were: (1) needing parenteral opioids or (2) active alcohol or drug abuse.

Bottom line: For me, this study alone seems not have enough external validity to decide about the decision to treat PE patients as inpatient vs outpatient. Although I think that ultimately some can be managed as outpatients, I'd like to see more studies.

Feel free to download this card and print on a 4'' x 6'' index card.

[MS Word] [PDF]

See other Paucis Verbis cards.

Lots of Twitter comments in the first 24 hours of the post, summarized on Storify:

PV card: Mnemonics to predict the difficult airway

Imitation is the highest form of flattery.

Keep that in mind as you see this PV card reviewing the most commonly used mnemonics to predict a difficult airway, which Dr. Javier Benítez wrote about in his post two days ago. Dr. Hans Rosenberg and Dr. Jeff Edwards promptly commented that these mnemonics were too good to NOT make into a PV card.

So here they are.

Feel free to download this card and print on a 4'' x 6'' index card.

[MS Word] [PDF]

See other Paucis Verbis cards.

Paucis Verbis: Electrolytes and ECG changes

Image from Life in the Fast Lane

The electrocardiogram can pick up all sorts of electrolyte abnormalities. The most common abnormalities revolve around high and low levels of potassium and calcium. Magnesium derangements typically have nonspecific findings. How do you keep things straight? To make things more complicated, multiple electrolyte derangements can occur at the same time, making ECG interpretation challenging.

Thanks to Dr. Steve Field (Resident at Resurrection EM program) for the idea and card. Also take a look at Life In the Fast Lane's extensive review of ECG abnormalities and their causes.

Feel free to download this card and print on a 4'' x 6'' index card.

[MS Word] [PDF]

See other Paucis Verbis cards.

Reference

Diercks DB, Shumaik GM, Harrigan RA, Brady WJ, Chan TC. Electrocardiographic manifestations: electrolyte abnormalities. J Emerg Med. 2004 Aug;27(2):153-60. Pubmed .

Paucis Verbis: EMTALA rules in the transfer of ED patients

In U.S. academic emergency departments, decisions to accept patients is typically easy, because you have ready access to on-call physicians. When in doubt, accept transfer patients and sort things out later.

• What are the obligations for those transferring patients to other EDs? 
• What do the EMTALA (a.k.a. "anti-dumping") rules say?
• When can you transfer unstable patients?

As a general rule, the liability falls upon the transferring site and physician. So be sure that your patient won't decompensate in the ambulance during transfer. So, don't transfer that CP patient who is getting ruled-out for an MI or ACS no matter how good they look. Patients need to be stable for transfer.

Anyone with pearls to share?

Thanks to @EMurgentologist for tweeting me the idea!

Feel free to download this card and print on a 4'' x 6'' index card.

[MS Word] [PDF]

See other Paucis Verbis cards.

Reference:

• AMA Ethics Resource Center powerpoint slides
• EMTALA site FAQ

Paucis Verbis: Delayed sequence intubation

A 40 y/o man presents with significant agitation and severe respiratory distress from a COPD exacerbation. His oxygen saturation is 75% on room air, and he has diffuse, tight wheezes on exam.

You prepare to intubate the patient using a rapid sequence induction protocol: etomidate, succinylcholine, 8-0 endotracheal tube.

Or do you? 

This Paucis Verbis card discusses the delayed sequence intubation (DSI) protocol made famous by Dr. Scott Weingart (EMCrit blog). Thanks to Dr. Michelle Reina (EM resident at Univ of Utah) and Dr. Rob Bryant (Intermountain Medical Center in Utah) for designing this helpful card. Rob has even implemented a DSI protocol in his ED. 

The card breaks down the reasoning and steps behind DSI. Anecdotally, ketamine has often calmed patients down enough during the preoxygenation phase to enhance oxygenation/ventilation so much so that intubation is not required. 

Feel free to download this card and print on a 4'' x 6'' index card.

[MS Word] [PDF]

See other Paucis Verbis cards.

References

Weingart SD, Levitan RM. Preoxygenation and prevention of desaturation during emergency airway management. Ann Emerg Med. 2012 Mar;59(3):165-75.e1. PubMed PMID: 22050948. Link to free PDF

Paucis Verbis: CHF likelihood ratios

A 50 y/o man with a history of CHF and COPD is brought in by ambulance in severe respiratory distress. He is sitting upright with a RR 30 and O2 saturation of 79% on room air.

Is this a CHF or COPD exacerbation?

This is a common dilemma faced in the ED. Fortunately there are likelihood ratios to help you risk stratify using a Bayes nomogram.

Note that the first table below (McCullough et al) enrolled ED patients WITH a known history of asthma or COPD. For the second table from JAMA (Wang et al), summative LRs for BNP are provided in ED patients with or without a history of asthma/COPD.

In the end, the most helpful positive findings which help you predict a CHF exacerbation causing dyspnea are (in descending order of LR):

• Exam: S3 heart sound
• CXR: Pulmonary edema
• Initial clinical judgment  
• CXR: Cardiomegaly 
• EKG: atrial fibrillation
• CXR: Pleural effusion
• EKG: Ischemic ST-T changes  
• Exam: Jugular venous distension (JVD)
• History of atrial fibrillation 
• Lab: BNP ≥ 100 pg/mL 
• EKG: Q waves 

Thanks to Dr. Daniel Kievlan (UCSF-SFGH resident) for the idea for this PV card.

Feel free to download this card and print on a 4'' x 6'' index card.

[MS Word] [PDF]

See other Paucis Verbis cards.

References

McCullough PA, Hollander JE, Nowak RM, et al; BNP Multinational Study Investigators. Uncovering heart failure in patients with a history of pulmonary disease: rationale for the early use of B-type natriuretic peptide in the emergency department. Acad Emerg Med. 2003 Mar;10(3):198-204. PubMed PMID: 12615582. Pubmed .


Wang CS, FitzGerald JM, Schulzer M, Mak E, Ayas NT. Does this dyspneic patient in the emergency department have congestive heart failure? JAMA. 2005 Oct 19;294(15):1944-56. PMID: 16234501. Pubmed . 

Paucis Verbis: Does this adult patient need blood cultures?

Do you order blood cultures for all your ED patients with a fever? Obviously no. What's your decision making process on ordering this test? There are really no findings or tests with high specificity (rules-IN bacteremia), except interestingly "shaking chills". Notice almost all the criteria listed below approach a likelihood ratio (LR) of 1.0. Two prediction rules do exist, however, to help you virtually rule-OUT bacteremia:

• SIRS
• Shapiro prediction rule

The list of LRs also will be helpful to show learners in the ED that an isolated serum WBC number is useless risk-stratifier.

Patient case:
A 55 y/o man with a PMH of hypertension presents with a community-acquired pneumonia on CXR, no fevers, no chills, no vomiting.

• Temperature 37.8 C, BP 160/90, HR 100, RR 16, Sat 100% RA
• Serum WBC 20K (no bands)
• Platelets 300K
• Creatinine 1.1 mg/dL

What is the patient's pre-test and post-test probability for having bacteremia? Use these helpful stats from the Rational Clinical Examination series from JAMA.

Answer to patient case:

• Start with 7% pretest probability for bacteremia with a community acquired pneumonia.
• Using the clinical prediction rules, the WBC 20K and HR 100 bpm are criteria for SIRS but do not fulfill the Shapiro prediction criteria. LR = 1.8 * 0.08 = 0.144. Post-test probability for bacteremia = 0.06%. 
• If the patient had instead a normal HR of 80 bpm, both the SIRS and Shapiro criteria would have been negative. LR = 0.09 * 0.08 = 0.0072. Post-test probability for bacteremia = << 0.1%.

Feel free to download this card and print on a 4'' x 6'' index card.

[MS Word] [PDF]

See other Paucis Verbis cards.

This discussion doesn't address WHETHER we should get blood cultures despite a risk for bacteremia in the setting of uncomplicated pneumonia receiving IV antibiotics or pyolenephritis with a pending urine culture.

Reference
Coburn B, Morris AM, Tomlinson G, Detsky AS. Does this adult patient with suspected bacteremia require blood cultures? JAMA. 2012 Aug 1;308(5):502-11. Pubmed .

Shapiro NI, Wolfe RE, Wright SB, Moore R, Bates DW. Who needs a blood culture? A prospectively derived and validated prediction rule. J Emerg Med. 2008 Oct;35(3):255-64. Pubmed .

Paucis Verbis: Overanticoagulation and supratherapeutic INR

I find it amazing that I know more non-emergency physicians virtually in the social media world rather than in person. Primarily through Twitter, I follow and am followed by medical educators from various specialties. If you haven't joined Twitter yet, I think it might be time. There is a whole world of collaboration and conversation going on in this virtual community, which crosses specialties and geography.

Last week, Dr. Javier Benítez (@jvrbntz) was tweeting a Question of the Day, referencing a 2010 Paucis Verbis card on overanticoagulation, which was based on the 2008 American College of Chest Physicians (ACCP) guidelines. About 8 minutes after I retweeted his question, Dr. Roy Arnold (@cholerajoe), a pulmonary/critical care physician kindly informed me that the 2012 ACCP guidelines have been out since February.

So this PV card is replacing the 2010 card with revised recommendations. To more in-depth discussion, definitely take a look at Dr. Scott Weingart's great podcast over at EMCrit. He helps to clarify holes which the 2012 ACCP guidelines don't really address such as:

• Question: What if the patient is minorly bleeding with a high INR? 
• Answer: Oral vitamin K and 15 mL/kg FFP

• Question: What if you only have the 3-factor PCC (factors II, IX, X) and not the recommended 4-factor PCC (factors II, IX, X plus factor VII)? The U.S. primarily has the 3-factor PCC. At my institution, we have bebulin.  
• Answer: If PCC is indicated, add recombinant factor VIIa or FFP to the 3-factor PCC to cover for factor VII.

2008 ACCP guidelines

New 2012 ACCP guidelines and pearls

Feel free to download this card and print on a 4'' x 6'' index card.

[MS Word] [PDF]

See other Paucis Verbis cards.

References

Holbrook A, et al; American College of Chest Physicians. Evidence-based management of anticoagulant therapy: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest. 2012 Feb;141(2

Suppl):e152S-84S. Pubmed .

Sort me! Paucis Verbis cards now catalogued

After much recent feedback on the poll about the Paucis Verbis cards (thanks to all who responded!), I see trends:

• Several have commented that it is getting increasingly difficult to find a card that they are searching for. There are over 100 cards now! So, I managed to figure out how to embed a Google Doc spreadsheet into the blog, which now allows you to sort and search for particular cards (minor HTML coding necessary). This list will permanently live on the Paucis Verbis page.

• Many are downloading cards manually. That's crazy, and I apologize for wasting your time. I made a zipped file with the first 100 PV cards. It's the top listed file in the spreadsheet. 

• There's a mix of readers using Dropbox and Evernote, so I'll continue to upload the cards there as well. I renamed the cards a little better in Dropbox so that the titles are easier to search (thanks to the anonymous user on the poll).

Poll: Is anyone using the Paucis Verbis cards?

Feedback is essential for continued growth and improvement in any longitudinal project that you work on.

Thus annually, I conduct a poll to see if I can improve anything on the blog. This year, I wanted to focus on the Paucis Verbis pocket cards. There are over 100 cards now, which are each based on recent peer-reviewed publications. I try to make them as practical as possible with the goal of improving evidence-based practice at the bedside.

I personally use these cards almost on every shift to help teach students and residents as well as a clinical reference tool. Really, who can remember ALL of the Canadian C-Spine Rules criteria or the PECARN criteria for head CT imaging in pediatric patients!?

Currently, one can access PV cards by:

• Reading from the blog website
• Manually downloading each PDF or DOC file
• Subscribing to my Dropbox PV folder
• Subscribing to my Evernote PV notebook

Because I am not tech-savvy enough to track downloads, and Dropbox/Evernote doesn't track subscriptions or usage, I have no idea if I am the ONLY person using these cards. If no one is using them, I may have to rethink what might be useful to the blog readership. I'm totally open to new ideas and change.

In that spirit, would you be kind enough to fill out a very brief, anonymous survey? Thank you so much for your time.

Click to read the already submitted responses.

Welcome to the blog team: Dr. Javier Benítez

It is with great pleasure that I introduce the newest member of the Academic Life in EM blog team -- Dr. Javier Benítez. He is an extremely active EM Twitter educator (@jvrbntz), who can efficiently convey key concepts in 140 characters or less! Got a short attention span? Follow Javier's Twitter feed.

Currently, Javier is posting "Question of the Day" tweets, which reference the Paucis Verbis pocket cards on this site. It is a perfect example of a bridge between blogs and Twitter for medical education. He'll also be posting on the blog as well.

Here's a short blurb from Javier:
I went to medical school in SUNY Downstate in New York City where I became interested in emergency medicine and critical care. My other interests include medical education and social media as a tool for medicine. My goals are to practice medicine in an academic institution where I can work closely with medical students and residents. I have used Academic Life in EM as a learning tool and it has proven to be quite effective. It’s an honor to take part on this blog. My hopes are to inspire and educate other learners about the wonderful world of emergency medicine.

Paucis Verbis: D-Dimer test

D-Dimer: To order or not to order?

That's the question when it comes to risk stratifying a patient for a pulmonary embolism with a low pretest probability. One should consider confounding conditions which may cause an elevated D-Dimer level. There's always confusion about what may cause an elevated D-Dimer besides venous thromboemboli. So I thought I would make a pocket card as a reminder.

Feel free to download this card and print on a 4'' x 6'' index card.

[MS Word] [PDF]

See other Paucis Verbis cards.

References

Wakai A, Gleeson A, Winter D. Role of fibrin D-dimer testing in emergency medicine. Emerg Med J. 2003 Jul;20(4):319-25. Pubmed. Free article

Paucis Verbis: Blunt cardiac injury

From www.ctsnet.org

Do you always get a troponin for patients who sustain blunt chest trauma?

Hopefully your answer is no. Of note, it is also NOT indicated as a screening test for those in whom you suspect a blunt cardiac injury (BCI). It can be normal in the setting of arrhythmias and it can be falsely elevated in the setting of catecholamine release or reperfusion injury from hypovolemic shock.

The initial screening test should include an EKG and a FAST ultrasound exam. If you have abnormal EKG findings, then a troponin is warranted (in addition to hospital admission).

Below summarizes a suggested algorithm from the recent EM Clinics of North America publication series. Definitive statements are challenging because there is no gold standard to diagnose BCI.

Feel free to download this card and print on a 4'' x 6'' index card.

[MS Word] [PDF]

See other Paucis Verbis cards.

Reference

Bernardin B, Troquet JM. Initial management and resuscitation of severe chest trauma. Emerg Med Clin North Am. 2012 May;30(2):377-400. Pubmed .

Paucis Verbis: Isopropyl alcohol

Continuing on the theme of Toxic Alcohols (osmolal gap, ethylene glycol, methanol), this Paucis Verbis card focuses on isopropyl alcohol toxicity, which is commonly found in rubbing alcohols. In this toxic alcohol, fomipezole is actually NOT indicated because you want to have alcohol dehydrogenase convert the toxic parent compound (isopropyl alcohol) into the nontoxic metabolite (acetone). 


Note that these are merely guidelines and you should tailor management plans with your toxicologist and nephrologist.

Feel free to download this card and print on a 4'' x 6'' index card.

[MS Word] [PDF]

See other Paucis Verbis cards.

References
Kraut JA, Kurtz I. Toxic alcohol ingestions: Clinical features, diagnosis, and management. Clin J Am Soc Nephrol. 2008;3:208-225. Pubmed .

Jammalamadaka D, Raissi S. Ethylene glycol, methanol, and isopropyl alcohol intoxication. Am J Med Sci. 2010;339(3):276-281. Pubmed .

Paucis Verbis: Toxic alcohols - Methanol

Continuing on the theme of Toxic Alcohols (osmolal gap, ethylene glycol), this Paucis Verbis card focuses on methanol toxicity. Useful are the American Academy of Clinical Toxicologists recommendations on when to administer an antidote (fomipezole) and when to perform hemodialysis. I redrew the flowchart based on what's relevant to the ED in the initial stages (I used Google Docs' Drawing feature).

Note that these are merely guidelines and you should tailor management plans with your toxicologist and nephrologist.

Feel free to download this card and print on a 4'' x 6'' index card.

[MS Word] [PDF]

See other Paucis Verbis cards.

References

Kraut JA, Kurtz I. Toxic alcohol ingestions: Clinical features, diagnosis, and management. Clin J Am Soc Nephrol. 2008;3:208-225. Pubmed .

Jammalamadaka D, Raissi S. Ethylene glycol, methanol, and isopropyl alcohol intoxication. Am J Med Sci. 2010;339(3):276-281. Pubmed .

Marraffa JM, Cohen V, Howland MA. Antidotes for toxicological emergencies: a practical review. Am J Health-Syst Pharm. 2012;69:199-212. Pubmed .

Barceloux DG, Bond GR, Krenzelok EP, Cooper H, Vale JA; American Academy of Clinical Toxicology Ad Hoc Committee on the Treatment Guidelines for Methanol Poisoning. American Academy of Clinical Toxicology practice guidelines on the treatment of methanol poisoning. J Toxicol Clin Toxicol. 2002;40(4):415-46. Pubmed .

Paucis Verbis: Toxic alcohols - Ethylene glycol

Following last week's Paucis Verbis card on calculating the osmolal gap, here is the first installment of the Toxic Alcohols cards. First up -- ethylene glycol. There are useful American Academy of Clinical Toxicologists recommendations on when to administer an antidote (fomipezole) and when to perform hemodialysis.

Here's a quick review of the metabolism of the different toxic alcohols. The parent compounds for ethylene glycol and methanol are innocuous and the metabolites are toxic.

Feel free to download this card and print on a 4'' x 6'' index card.

[MS Word] [PDF]

See other Paucis Verbis cards.

See Dr. Leon Gussow's great review on The Poison Review and tips of a recent Annals of EM paper on identifying a small subset of patients with ethylene glycol who did well despite NOT receiving hemodialysis.

References

Kraut JA, Kurtz I. Toxic alcohol ingestions: Clinical features, diagnosis, and management. Clin J Am Soc Nephrol. 2008;3:208-225. Pubmed .

Jammalamadaka D, Raissi S. Ethylene glycol, methanol, and isopropyl alcohol intoxication. Am J Med Sci. 2010;339(3):276-281. Pubmed .

Marraffa JM, Cohen V, Howland MA. Antidotes for toxicological emergencies: a practical review. Am J Health-Syst Pharm. 2012;69:199-212. Pubmed .