A fatal medication error

A 75-year-old woman died at Vanderbilt University Medical Center after receiving intravenous vecuronium, a drug that causes muscle paralysis, instead of Versed, a sedative.

Here’s what happened.

She had been recovering well from an intraparenchymal brain hematoma after a fall. While awaiting a full body positron emission tomography (PET) scan in the radiology department, the patient said she was anxious about being in the machine because she was claustrophobic.

A doctor ordered Versed 2 mg IV in the electronic medical record at 2:47 PM. Two minutes later, the pharmacy verified the order. The radiology department staff said they could not give the medication because they were very busy and the patient would need to be monitored.

So nurse A, who was functioning as the “help all” nurse was asked by the patient’s nurse, nurse B, to go to radiology and give the medication. At 2:59 PM, nurse A went to the automated dispensing cabinet (ADC) and searched for Versed in the patient’s profile. When she couldn’t find the drug listed, she selected the “override” setting to search for the drug. She entered the first two letters of the drug, VE, and clicked on the first medication that popped up.

Can you be held liable for resuscitating a patient who has a DNR order?

A New Mexico woman, suffering from Dercum’s disease (adiposis dolorosa) which causes painful fatty tumors, is suing a Santa Fe hospital and an emergency physician claiming she was the victim of two negligent acts in 2016.

One, according to the Albuquerque Journal, she told hospital personnel she was allergic to Dilaudid but went into cardiac arrest after receiving an injection of the drug.

Two, despite the presence of a lawfully executed “do not resuscitate” (DNR) advance directive, she was successfully resuscitated and now faces continued pain and medical bills.

The staff had been aware of her DNR order and had even issued her a purple bracelet labeled “DNR.” However since the cardiac arrest was allegedly caused by an allergic reaction to Dilaudid, the staff may have felt her problem was not related to her illness and would likely result in a successful resuscitation.

While researching this subject, I found several instances of patients or families suing hospitals and doctors for failing to heed a DNR order or what some have called “wrongful life.”

However, I found only one major case that had gone to conclusion. A Georgia woman had both an advance directive and a healthcare proxy—her granddaughter. She was admitted to a hospital for a cough and eventually required a thoracentesis. The healthcare proxy agreed to allow the procedure to be done but specifically said her grandmother did not want intubation or mechanical ventilation.

A 2017 paper in The Journal of Clinical Ethics said the patient was temporarily intubated and ventilated during the thoracentesis. She was extubated, but a bout of respiratory distress was treated with intubation and mechanical ventilation again without consulting the granddaughter. The patient died two weeks later.

The granddaughter sued, and the hospital settled for $1,000,000. I believe this is the first such case settled for that much money. The biggest problem was failure of the doctor to communicate with the healthcare proxy.

Many issues in medicine are not black or white. Here’s the other side of the story. An elderly Boston man suffered a cardiac arrest in a hospital CT scanner and was resuscitated. The resident who treated him wrote that during the code, a nurse discovered a 6-year-old advance directive saying he did not want to be resuscitated in his chart.

But the code team noted he had walked into the hospital for the test and felt certain they could save him. They contacted his son and healthcare proxy who said “My father would want everything done to save his life.” The code was successful. He was weaned from mechanical ventilation and extubated after a few hours. He thanked his doctor and was discharged from the hospital two days later.

Some take-home points:

A DNR order and an advance directive may not necessarily be the same. For more information, read an interview with the plaintiff’s lawyer in the Georgia case.

Whether to resuscitate a patient or not may depend on the circumstances [e.g., whether an event is likely reversible or not], the wording of an advance directive, and/or the wishes of the healthcare proxy.

If possible, explain the possible scenarios and outcomes of resuscitation and DNR to your patients and their families well before a cardiac arrest occurs.

Communicate with patients and their healthcare proxies.

Appendectomy outcomes in the modern era

Finally we have some data on the current rate of complications of appendectomy for uncomplicated appendicitis. But that’s not all. This new paper, published online in the journal Surgery, reveals much about the diagnosis, technique, and outcomes of appendectomy in the United States.

Using data from 115 hospitals participating in the National Surgical Quality Improvement Program, researchers at UCLA analyzed the results of 7778 adult patients undergoing appendectomy for simple appendicitis in 2016.

A Venezuelan surgical resident appeals for help

I received the following email. It has been edited for length and readability.

I assume you know is happening in my country, Venezuela. Basically a communist-socialist party has taken control of the government for 20 years now and has the citizens under the worst economic crisis of South America along with one of the most important refugee situations of the continent.

I can write 300 pages about it, but I believe I’ve said enough. As you may know, EVERYTHING has gone to bad situations in this country: public services, roads, HOSPITALS, UNIVERSITIES, food shortage, lack of water and electricity, freedom of speech, and the list goes on and on.

A Revolutionary Experience!

Listen as renowned surgeon Leo Gordon reads his epic story about pancreatic insufficiency and the American Revolution. Based on a true story. The podcast is 15 minutes long and worth every second of it.

“Number of medical students pursuing surgery specialty drops by half”

That was the headline in a September 10 Becker’s ACS Review article. The first sentence of the piece was more specific, “Only 4 percent of medical students surveyed in 2018 said their chosen medical specialty is general surgery, compared with 8 percent in 2016, according to Medscape's Medical Student Life & Education Report 2018.”

This caused some consternation among general surgeons on Twitter. I tweeted, “Interesting. Lifestyle is finally catching up to us. I think it will get worse.”

How to interpret the literature: A new series of posts

The Salty Statistician will be a recurring feature of this blog wherein we ask statisticians in medicine to break down articles from the surgery literature and assess whether the reported conclusions are supported by the data. Let’s look at this study:

Groh MA et al. Is Surgical Intervention the Optimal Therapy for the Treatment of Aortic Valve Stenosis for Patients With Intermediate Society of Thoracic Surgeons Risk Score? Annals of Thoracic Surgery.

The authors attempted to address the question of whether aortic stenosis patients deemed “intermediate risk” [IR] for surgical aortic valve replacement [AVR] are best treated with open surgery or transcatheter AVR. The authors looked at 1,144 patients who received surgical AVR from 2008-2014 at a single center focusing on the 620 “intermediate risk” patients. At the end of the follow-up period, 72 had died.

Unfortunately, major methodological issues undermine the paper’s conclusions. Fortunately, this provides an excellent teaching opportunity.

First, the authors inappropriately used logistic regression to analyze independent predictors of mortality. Logistic regression treats the outcome as a simple “Yes” or “No” variable, while ignoring the time-at-risk. This study included patients treated over a six-year period (2008-2014) who therefore have substantial differences in the amount of time at risk. Consider the following hypothetical patients.

Patient A treated in 2008 and died in 2014 surviving six years after surgery. The logistic regression model simply counts patient A as “dead.”

Patient B treated in 2014 and alive in 2017 but dies in 2018, after the data were analyzed and the paper published. He survived four years after surgery and in the logistic regression model, counts as “alive” since data were analyzed in 2017.

Patient A lived for six years after surgery, but counts as “worse” in the analysis than Patient B who only lived for four years because of the time at which the data were “frozen” and analyzed. Of course, this is unavoidable in long-term outcomes studies, but one must choose an appropriate statistical method that accounts for time-at-risk.

Cox proportional-hazards models are more appropriate for a long-term survival outcome than logistic regression. When building a Cox model, one specifies both the current status (i.e., alive/dead) as well as an amount of follow-up time. For example, Patient A is “dead” with six years of follow-up; Patient B is “alive” but with only three years of follow-up. This provides a proper assessment of how strongly the independent variables are associated with risk of mortality while accounting for the unequal follow-up time.

Second, the authors state their data supports the conclusion that “SAVR is the optimal therapy for most of the patients” in the IR group in comparison to TAVR. However, their paper lacks any data on outcomes in IR patients who were treated with TAVR. Why the authors believe presenting data from a series of SAVR patients is sufficient to claim that SAVR is the “optimal therapy” absent any comparison data on patients treated with TAVR is unclear. Randomized controlled trials have more appropriately compared SAVR and TAVR in the IR population. Link here and here.

Which patients should receive surgical AVR versus transcatheter AVR is a good question, but to answer it, the paper used an incorrect approach.

Final Rating (1-5 Scalpels): 1 Scalpel - significant methodological issues

This issue of the Salty Statistician was written by Andrew Althouse (@ADAlthousePhD), currently an Assistant Professor of Medicine at the University of Pittsburgh as well as Statistical Editor of Circulation: Cardiovascular Interventions.

We intend this series to focus on work that is perceived to have a high impact on clinical practice, so we welcome reader suggestions. If you have a paper that you would like to see reviewed as part of the Salty Statistician series, please tweet @Skepticscalpel or @ADAlthousePhD or email SkepticalScalpel@Hotmail.com. We cannot promise that all submissions will be reviewed in this space, but we will do our best.

A perforated colon case report raises a few issues

When a medical paper is featured on the Daily Mail website, you know it’s going to be something odd.

An autistic young man with prior hospitalizations for chronic constipation and megacolon was admitted to a hospital in London, UK with a markedly distended abdomen. A CT scan showed a dilated rectum and colon with a diameter as large as 18 cm (7 inches).

He was treated conservatively for two days with laxatives. Enemas were ordered, but the patient declined. He then developed peritonitis, kidney dysfunction, mental status changes, and metabolic acidosis.

Patient worries after accessing his chest x-ray report online

I received an email a few days ago. It has been edited for length and clarity.

I would like some advice please. I am a 46-year-old male with an off and on cough for 4-5 months. I have never smoked. After my primary care physician examined me, he ordered a chest x ray. A few days later I got a call from the doctor who said my x ray was normal. I was happy to hear that, but I am enrolled with My Chart which allows you to review your results online. Well, I read it and to me it doesn't sound what you would call totally normal, but I have no medical training so I could be wrong. I copied and pasted the report from the radiologist below. What concerns me is the "elevation" he refers to and using the word "fairly" clear lungs. Should I ask for another test or see another doctor for an opinion? If I was your family member would you suggest looking into this more?

CLINICAL INFORMATION: Cough

FINDINGS: The frontal view demonstrates fairly clear lungs with slightly increased elevation of the left hemidiaphragm compared with the prior study. This may be at least partially caused by air in the adjacent bowel. No pleural effusion or pneumothorax is noted. The cardiomediastinal silhouette is unremarkable. The lateral view demonstrates fairly stable appearance of the lung bases compared with the previous study.

More proof medical error is not the third leading cause of death

Over the last 20 years, estimates of the number of deaths caused by medical error have risen from 44,000-98,000 in 1999 [1] all the way up to 440,000 [2] and 251,000 [3]. Despite my efforts [4, 5] and those of others [6, 7] to debunk these guesses, they continue to permeate the lay press. If you Google “third leading cause of death,” you will find countless headlines naming medical error.

The papers claiming medical errors cause so many deaths assume that all complications result from errors and all complications are preventable. They extrapolate their final numbers from small studies not designed to or capable of estimating deaths due to medical error nationwide.

The most recent figures available from the National Hospital Discharge Survey [8] state that the number of hospital deaths dropped from 776,000 in the year 2000 to 715,000 in 2010. It is simply not plausible that 251,000 (35%) or 440,000 (61%) inpatient deaths are due to medical error.

A recent study [9] from Norway found that of 1000 consecutive in-hospital deaths reviewed, only 42 (4.2%) were judged to be probably (greater than a 50% chance) to definitely avoidable.

Everything you ever wanted to know about operating room head coverings

In case you might want to challenge your hospital’s policy on the subject, I have gathered all of the recent research I could find on surgical head wear.

In response to a 2013 question from a reader, I blogged about the complete lack of evidence that OR staff hair caused wound infections or any other problem. After a similar question from another reader three years later, I pointed out nothing had changed.

Finally a 2017 paper in the journal Neurosurgery appeared online comparing the incidence of wound infections in clean cases for the 13 months before and the 13 months after the institution of a ban on the wearing of the traditional surgeons’ ca`p. Over 15,000 patients were included in the study which found no statistically significant difference in the rate of wound infections.

Are neckties dangerous to your health?

Wearing a necktie significantly decreases cerebral blood flow says a new study in the journal Neuroradiology. This finding caused a minor flurry of activity on Twitter, and as usual, the press sensationalized and misinterpreted the study’s results.

Here’s a headline from the Deccan Chronicle: “Wearing ties hamper [sic] productivity in office; here’s why.” The sub- heading is “Study suggests men who wear T-shirts in the office may produce better work.” T-shirts were not mentioned in the paper. The name of the journal that published it was incorrect in the article too.

Forbes didn’t do much better. It’s lede is “Neckties are stupid. Could they also make you stupid?” The paper said nothing of the kind.

Papers about robotic surgery outcomes may be swayed by payments from the manufacturer

In 2015 alone, the top 20 surgeons receiving payments from Intuitive Surgical Inc., makers of the da Vinci robot, collected a median of almost $142,000. Of those surgeons, 12 have published 37 papers about the robot with 27 (73%) reaching strongly favorable conclusions about the robot’s effect on clinical outcomes, feasibility, or safety. Nine (24%) were equivocal, and one (2%) study was negative.

These results appeared in a paper published online in the American Journal of Surgery by investigators from the University of Michigan.

The 37 papers consisted of 36 observational studies and 1 randomized controlled trial. Robotic surgery patient outcomes were compared to patients operated on in the same institution or by the same surgeon in 11 papers, patients operated on in a different institution or by a different surgeon in 4 studies, to a database in 4, and to previously published papers in 2 instances. No controls or comparisons were used in 16 (43%) papers.

Intuitive Surgical sponsored six of the studies, all of which had positive outcomes.

According to the CMS Open Payments website, compensation received by the top 20 surgeons ranged from $106,176 to $325,164. Among the top 20 earners were 11 general surgeons, 4 colorectal surgeons, 3 thoracic surgeons, and 2 gynecologists.

Three of the 37 papers contained no conflict of interest disclosure statements.

Several limitations of the study were listed. Most journals favor publishing papers with positive results. It may be that surgeons not receiving any industry payments might have published similar numbers of positive studies. The accuracy of the Open Payments site has been questioned but it is the best resource we have currently.

The authors described their paper as a pilot study and called for more research on not only Intuitive’s effect on the medical literature but also the influence of industry in general.

The paper also illustrates the woeful state of research on robotic surgery—a device that has been used on patients for almost 20 years.

We need less research

“We need less research, better research, and research done for the right reasons. Abandoning using the number of publications as a measure of ability would be a start.” Although I have expressed similar sentiments in blog posts [here and here], I didn’t say it. It was written by Douglas Altman, a well-known statistician and researcher who died in June.

Altman made that statement in a 1994 BMJ article entitled “The scandal of poor medical research.” Here we are, 24 years later, and nothing has changed. In fact, thanks to the rise of predatory journals, things are much worse.

Altman lamented research containing flaws such as “the use of inappropriate designs, unrepresentative samples, small samples, incorrect methods of analysis, and faulty interpretation” and felt many poor studies were the result of pressure on researchers to publish.

Some data is better than no data at all

Do you believe that?

I heard it frequently when the infamous Propublica Surgeon Scorecard first appeared three years ago. Back then I blogged about it saying “To me, bad data is worse than no data at all.”

A recent study in BJU International confirmed my thoughts about this type of publicly posted data and identified a previously unreported issue. The paper attempted to determine whether the public was able to accurately interpret statistics used in the Surgeon Scorecard. It turns out they were not very good at it.

Investigators from the Department of Urology at the University of Minnesota surveyed 343 people who attended the Minnesota State Fair in 2016. Those who took the survey had a median age of 48, were 60% female, 80% white, and 60% college educated. Their median annual income was $26,550 with an interquartile range of $22,882-$32,587.

The dark side of academic research

A new study found several senior academic surgeons had published papers in what used to be termed “predatory journals.” The newer, gentler term is “solicited publishing,” but it defines the same pay-to-play, low quality publications.

Surgeons from the University of California, San Diego examined 110 emails sent to the senior author from 29 publishers during a six-week period and early 2017. Nearly all were requesting manuscript submissions. The 29 publishers represented 113 different surgery journals most of which had existed for two years or less. Only 12 were indexed in PubMed, and of the 9 that mentioned a self-reported impact factor, the median was 0.24 which means they had less than one citation per article in the last two years. The median publication fee for the 88 journals posting the information was $755.

Emails from the publishers contained a mean of 9.6 grammatical errors, possibly because more than half had addresses in foreign countries, and of those with US addresses, 30% were residential.

The requirement that residents must be involved in research should be abolished

In a 2012 blog post called “Things that puzzle me about surgical education,” I wrote the following:

“There was the emphasis that still exists today on making sure every resident did research. At last, some are questioning the value of this for the average clinical surgeon. Contrary to the prevailing wisdom, there is no evidence that a resident who is dragged kicking and screaming through a clinical research project or who spent a year in someone’s lab really learns anything about research or how to read and understand a research paper.”

Nothing has changed.

According to the ACGME Program Requirements for Graduate Medical Education in General Surgery Section II.B.5.e: Clinical and/or basic science research must be ongoing in the residency program; based at the institution where residents spend the majority of their clinical time; and performed by faculty with frequent, direct resident involvement.

Family of late pop singer Prince sues everyone for malpractice

According to the New York Times, “The suit claims that Prince’s death was a “direct and proximate cause” of the hospital failing to appropriately diagnose and treat the overdose, as well as its failure to investigate the cause and provide proper counseling.”

The suit names a hospital and an emergency department physician in Moline, Illinois where Prince’s private jet made an emergency landing when he became unresponsive during a 2016 flight home to Minnesota from a concert in Atlanta.

An employee of his told paramedics who met the plane that he “may have taken a Percocet.” After Prince regained consciousness, he supposedly told the ED doc he had taken two Percocets, but she did not believe him because it had taken two doses of Narcan, an opioid antidote, to revive him.

Friends said he refused all testing including blood and urine toxicology because he was trying to keep his addiction a secret.

2018 Residency Match Update

The National Resident Matching Program Advance Data Tables for the 2018 Main Residency Match again show an increase in the number of first-year positions offered, going from 28,849 in 2017 to 30,232 this year.

Of the 18,818 seniors graduating from US allopathic medical schools, 17,740 (94.3%) matched, 1078 (5.7%) did not match, and 474 withdrew or did not submit a rank list. The 5.7% who went unmatched was identical to last year’s figure.

The 1511 graduates of US allopathic medical schools from previous years did not fare as well with 43.8% matching and 56.2% going unmatched—slightly worse than the 2017 percentages.

What is the worst way to combat school shootings?

Please read carefully because there might be a test.

A school district in Pennsylvania placed a 5 gallon bucket of rocks in each classroom two years ago. If locking and barricading the classroom door does not work, the students have been instructed to throw rocks at the would-be shooter instead of hiding under their desks.

According to a Buzzfeed story, the school superintendent for Schuylkill County believes the rocks serve as a powerful deterrent. He said, “If an armed intruder attempts to gain entrance to any of our classrooms, they will face a classroom full of students armed with rocks. And they will be stoned.”

Maybe it’s working. Since the arrival of the rocks, there have been no shooter incidents in any Schuylkill County school.

The decline and fall of the rectal exam

For almost 20 years, the value of the digital rectal exam (DRE), a long time staple of the complete examination of the trauma patient, has been questioned. Performing a rectal examination on all trauma patients is no longer advocated except for a few specific indications.

As recently as two months ago, trauma surgeon Michael McGonigal blogging at The Trauma Pro reinforced the message. Because a rectal examination is so uncomfortable for patients already traumatized and its yield is so minimal, he advocates doing it in only patients with spinal cord injury, pelvic fracture, and penetrating abdominal trauma. For a more extensive discussion of the topic, see Life in the Fastlane, an emergency medicine blog.

Can data in electronic medical records be trusted?

If the subject is respiratory rates, the answer is “No” according to a recent study. The authors reviewed the records of 28,500 patients over 220,000 hospital days and found recorded maximum respiratory rates “were not normally distributed but were right skewed with values clustered at 18 to 20 breaths per minute.”

The figure below shows maximum respiratory rates compared to heart rates which were normally distributed.

Reminder: Most sources say the normal respiratory rate of an adult ranges from 12 to 20 breaths per minute.

More negative data about the nonoperative management of simple appendicitis

If you think I am the only one urging restraint in the adoption of nonoperative management of patients with uncomplicated appendicitis, you are wrong. A pediatric surgeon and a research fellow from Harvard and Massachusetts General Hospital have recently published their thoughts on the matter online in Annals of Surgery.

They call their opinion piece “Ulysses Syndrome” because they liken the fate of those undergoing nonoperative management to the “10-year ordeal filled with unexpected peril and ample misfortune” that befell Ulysses while attempting to go home.

Here are a few highlights.

How the public is misinformed about the outcomes of CPR

A survey of 1000 volunteer adults found 71% regularly watched medical television dramas, but only 12% said the shows “were a reliable source of health information.”

The participants were given some brief vignettes describing scenarios where CPR was administered—a 54-year-old who suffered a heart attack at home and received CPR by paramedics, an 80-year-old with a postoperative cardiac arrest in the hospital after surgery, and a post-traumatic arrest in an 8-year-old.

Those surveyed estimated CPR success rates at 57% to 72% and rates of long-term survival with neurologic recovery at 53% to 64%.

Perforated appendix not seen on CT scan

From an email received two days ago. Posted with permission and edited for length and clarity.

I came across your blog while looking for information on something puzzling that happened to my sister. I read the blog on CT scans and appendicitis* and went through all of the comments section. I couldn't find a case like my sister’s.

She has been sick off and on for the last two months. It began with what seemed like a bad stomach virus, fever, throwing up, diarrhea, gas pain, bloating, and stomach cramps. She brushed it off as a 24 hour type thing, stayed home from work a few days, and felt better but never returned to normal. She would have intermittent stomach upset and began to have weight loss. About 3 weeks ago, she went to see her GP who ran some tests (antibody tests, no CBC, chem 7 or normal work up) and diagnosed her with gluten intolerance.

"The Resident"

A new medical drama with the same old characters.

The show opened with the chief of surgery in the middle of a rather bloody open, not laparoscopic, appendectomy.

The circulating nurse started taking selfies with her phone; the anesthesiologist was distracted; the patient started moving; blood spurted all over the surgeon.

According to a nurse, the patient lost 2 liters of blood in 20 seconds.

What artery, other than the aorta, could he possibly have cut that would bleed so much? The chief of surgery just stood there. I yelled at the TV, “Put pressure on it for God’s sake.“

Finally, they started CPR and the surgeon seemed to be packing the wound.

Facial exercises to make you look younger? I don't think so.

One would think a study covered by the New York Times would be both scientifically valid and important. Apparently, that is not always the case.

Under the headline “Facial Exercises May Make You Look 3 Years Younger” is a story about a research letter published in JAMA Dermatology. The Times article concludes with a quote from the lead author, “But for now, it is reasonable to consider contorting and pinching up your face if you wish to try to look younger.”

Is it reasonable? Let’s see if this 1½ page research letter proved its point.

Is chronic pain after inguinal hernia repair a big problem?

Yesterday one of my twitter followers posted this:

He was referring to a paper in the British Journal of Surgery that said 15.2% of patients who had inguinal herniorrhaphies complained of severe chronic pain one year after the surgery. Open hernia repairs caused significantly more chronic pain than did endoscopic total extraperitoneal [TEP] repairs, but the reoperation rate was significantly higher for TEP procedures.

The study included almost 23,000 patients and was based on data from the Swedish Hernia Registry and a questionnaire sent to the patients one year after their initial hernia operation. Pain was rated on a scale of 1 to 7 and was considered chronic if it was present for more than 3 months and interfered with daily activities.

The recurrence rate for the 18,000 patients who had open anterior mesh repair was 3.4% compared to 23.3% for the 2688 who had TEP repairs.

The authors concluded that the trade-off for less pain was an increased recurrence rate. Only 232 [1.39%] of the 1666 patients with recurrent hernias had undergone repeat herniorrhaphy.

Some of the comments on Twitter were as follows:

When I was in private practice in the early 1980s, I invited all of my post-op hernia patients to return to my office for yearly follow-up at no charge.

One day, a nice elderly gentleman was sitting in the exam room when I walked in. After an exchange of pleasantries, I asked him how his hernia repair was doing. He said he had no problems and was quite happy.

I had him stand up and when he lifted his gown, I saw a softball-sized recurrent hernia. Ever since then, I have not trusted any studies in which follow-up was not done in person.

Based on my experience, the recurrence rate after groin hernia repairs could even be higher than the Swedish study reported.

The incidence of chronic pain after inguinal herniorrhaphy may depend on how surgeons follow their patients.