Up to one-quarter of the 1.6 million amputees in the United States develop painful neuromas that can interfere with even the most carefully fitted prosthetic devices.

Neuromas develop because axons sprouting from the proximal nerve stump have no distal target in which to reinnervate. 

Surgeons treat neuromas with targeted nerve implantation (TNI), a procedure that implants the proximal amputated nerve stump onto a surgically 

portion of a nearby muscle at a secondary motor point. If successful, the procedure creates regenerating axons that spread into the intramuscular motor nerve branches rather than from a neuroma. As TNI may prevent or diminish neuroma-related pain, scientists continue to evaluate TNI’s value and efficacy.

Researchers from the University of Washington in Seattle structured a study to determine whether TNI prevents primary neuroma-related pain in the setting of acute traumatic amputation, as well as address the procedure’s potential to reduce established neuromal pain in upper- and lower-extremity amputees. Their results appear online April 11, 2014, in 

Clinical Orthopaedics and Related Research.

The researchers examined 2 groups of patients who were under the care of a single surgeon. Group 1 consisted of 12 patients who underwent primary TNI for neuroma prevention at the time of acute amputation, while Group 2 included 23 patients who had developed neuromas after amputation and underwent neuroma excision with secondary TNI. Using medical records as a data source, the authors used the presence or absence of palpation-induced neuroma pain at the last follow-up as a primary outcome measure.

Patients in Group 1 were followed for at least 8 months while those in Group 2 were followed for at least 4 months. In Group 1, 92% were free of palpation-induced neuroma pain at last follow-up, and in Group 2, 87% remained pain-free. Only 8% of patients developed neuroma pain within 20 months. Since the current overall rate of neuroma after amputation is up to 25%, the rates reported in this study represented an improvement.

Although the study findings were positive, they were limited by the small sample size and the possibility that patients’ pain was caused by something other than neuroma, such as ossification. The researchers noted that by providing a distal target for regenerating axons, TNI may effectively treat neuroma pain in amputees. However, the procedure had little effect on other types of pain related to amputation, including centrally mediated phantom limb pain.

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Treating Amputees in Pain with Targeted Nerve Implantation

Many healthcare institutions and watchdog organizations look at 30-day survival after surgery as a measure of quality, but can those metrics adversely influence patient outcomes? A 

 published online April 9, 2014, in the journal 

A research team from the Johns Hopkins University School of Medicine in Baltimore, MD, set out to determine whether the 30-day survival quality metric may have unintended consequences for patients. To do so, they conducted a retrospective observational study using the Nationwide Inpatient Sample from 2005 through 2009 and reviewed all admission records coded for major cardiac surgery procedures. Then, they analyzed the day-by-day hazard function for all-cause in-hospital mortality at one-day intervals.

The authors found the pattern of postoperative mortality shifted on day 6 and day 30. They explained the shift on day 6 as potentially related to the difference between routine recovery and a complicated postoperative course. By day 6, patients who have done well have already been discharged, and those who have not may die within the first week.

According to the researchers, the change in hazard from day 30 to day 31 was 35% higher than on any other one-day increment. However, the abrupt increase in mortality at day 30 was not associated with an obvious organic cause.

In the interim between days 6 and 30, surgeons may be motivated to use more aggressive treatment, so the quality measure is positive, the authors explained. Patients may be treated despite inevitable death and at increased patient and family discomfort. They may also spend unnecessary, excessive days in intensive care units and die there instead of in more appropriate palliative care of step-down units.

The authors said further studies are needed to establish causality in cardiac surgery, and because they do not believe the phenomenon is exclusive to cardiac surgery, they indicated studies on other surgeries are needed, as well.

Many healthcare institutions and watchdog organizations look at 30-day survival after surgery as a measure of quality, but can those metrics adversely influence patient outcomes?

Are 30-day Survival Measures Related to Spikes in Mortality After Cardiac Surgery?

Although ruptured abdominal aortic aneurysm (rAAA) is rare and usually asymptomatic, it is a rapidly life-threatening condition with outcomes that differ greatly by country.

 looked at the differences in rAAA outcomes between the United States and England with an eye toward improving care. Using the United States’ Nationwide Inpatient Sample and England’s equivalent database, the Hospital Episode, the paper 

 for all patients admitted to a hospital with rAAA from 2005 to 2010, comparing in-hospital mortality, mortality after intervention, and the decision to follow non-corrective treatment.

Both databases contained large numbers of rAAA records; in the US, the researchers found 23,838 patients, and in England, they identified 11,799 patients.

According to the study authors, patient mortality was significantly lower in the US than England. Additionally, American surgeons were more than twice as likely to offer open or endovascular repair than English surgeons, with surgeons discussing repair with more than 80% of patients in the US. As a result, patients were more likely to opt for endovascular repair in the US than in England. English patients were more likely to receive non-corrective treatment, or supportive care without open surgical or endovascular rAAA repair.

Both countries had similar rates of post-intervention mortality, with approximately 42% of patients dying. However, more American patients were discharged to rehabilitative facilities than English patients, who were more likely to be discharged to home. All patients were less likely to die if they underwent endovascular repair, were admitted on a weekday, or were treated in a hospital with a higher rAAA operative volume, bed capacity, or teaching status.

The researchers determined in-hospital survival, intervention rates, and uptake of endovascular repair were lower in England than the US. In both counties, patients treated in larger teaching hospitals that performed many rAAA repairs had better outcomes than others. They suggested England’s overall survival from rAAA would improve if UK surgeons offered interventions to a greater proportion of patients — a belief that is consistent with other published clinical data indicating that aggressive management decreases overall mortality from rAAA.

Although ruptured abdominal aortic aneurysm is rare and usually asymptomatic, it is a rapidly life-threatening condition with outcomes that differ greatly by country.

Improving Outcomes for Ruptured Abdominal Aortic Aneurysm

Anniversaries often prompt reflection, and the 2013 Boston Marathon bombing is no exception.

Among the many reflective pieces published in the medical literature, one stands out: an 11-page 

 featured in the April 2014 issue of the 

walked readers through the case of a 34-year-old man who suffered traumatic injury that day.

The patient arrived at Massachusetts General Hospital after undergoing a below-knee amputation of his right leg at the scene. The piece described the decisions made at the bombing site and in the emergency department, including amputation, tourniquet use, concerns that the tourniquet was insufficiently tied, burns, and foreign body complications.

The study provided interesting details on treatment following this type of event. For example, few healthcare professionals realize that when surgeons remove foreign bodies and shrapnel during events like the Boston Marathon bombing, the Federal Bureau of Investigations (FBI) works with the hospital to take possession of amputated limbs and foreign bodies as evidence, so chain of custody is an important concern.

Like many others, this patient developed rhabdomyolysis with creatine kinase levels exceeding 10,000 U/L, a condition that increases risk of acute renal failure. In response, the team used early, aggressive fluid resuscitation and electrolyte substitution to increase renal perfusion and stabilize urinary output.

A key section of the article addressed the multidisciplinary approach to critical care medicine and described exemplary healthcare collaboration. This patient received care from otolaryngology, psychiatry, rehabilitation medicine, and physical therapy specialists. Although he did not show signs of post-traumatic stress disorder (PTSD), the treatment team took every measure to prevent its development. They also dealt with the patient’s intractable pain, sleep disturbances, and quality of life.

The facility used a family-centered critical care medicine model and asked the patient's fiancée, a trained nurse, to participate in daily rounds and stay in the room overnight. The team also spoke daily with the patient’s father, and the patient himself contributed to this study by being present for rounds and answering questions.

However, an intrathoracic foreign body found in the patient was a challenge that required extensive imaging and a careful plan due to its proximity to the heart. Ultimately, the team decided the concerns were not urgent and deferred management. In addition, the case study described the patient’s blast injuries and explained how they differed from other injuries.

Military personnel who had undergone leg amputations visited the patient in the intensive care unit to discuss their successful rehabilitation, which served as an example that fully independent vocational and social functioning was possible and likely. The case study also described the patient’s anger and frustration, despite his relief at having survived the bombing.

Overall, the patient reported that his care was exceptional. When asked what could have been better, he gave an expected yet humorous answer: the food.

Lessons in Critical Care from the Boston Marathon Bombing

Until recently, repairing aged or diseased aortic valves required open-heart surgery and valve replacement with an artificial piece. Unfortunately, many patients who need valve replacement are considered inoperable or high risk, as they are too sick or frail to undergo the traditional operation and its lengthy recuperation period.

considered high risk for standard valve replacement surgery

In November 2011, the US Food and Drug Administration (FDA) approved a transcatheter aortic-valve replacement (TAVR) system called the Sapien Transcatheter Heart Value for aortic stenosis patients who are 

. This TAVR is constructed of cow tissue and polyester and supported with a stainless steel mesh frame. It is inserted using a delivery catheter via a 1-inch cut in a leg artery, through which the surgeon guides the catheter to the heart and places the device inside the dysfunctional valve.

 was based on a study of 365 patients who received the Sapien valve. Although those patients were 2.5 times more likely to experience a stroke and had 8 times as many vascular and bleeding complications than the control group, 69% of the Sapien patients were alive at one year compared to 50% of control patients. Currently, the system’s manufacturer, Edwards Lifesciences Inc., is conducting additional studies with next-generation devices.

On January 17, 2014, the FDA approved a similar TAVR device, Medtronic Inc.'s CoreValve, for patients who are unable to undergo aortic-valve surgery. Its approval was based on the 

, a study of patients who could not have conventional aortic-valve replacement surgery due to risk factors that increased mortality risk to 15% or more. At one year, 75% of patients were alive, while 25.5% of patients had died or experienced a major stroke — a rate approximately 40% lower than the FDA-identified acceptable rate. More than 20% of patients needed pacemaker implantation after surgery. This TAVR system was associated with very low stroke and paravalvular leak rates.

At the 2014 American College of Cardiology (ACC) scientific meeting, held March 29-31, 2014, in Washington, DC, researchers presented a new 

 on the CoreValue TAVR system, which appeared online in the 

. Across 55 surgical centers, they enrolled 795 patients with severe aortic stenosis at increased surgical risk and randomly assigned them to either TAVR (n=394) or surgical aortic-valve replacement (n=401). The primary endpoint was death from any cause at one year.

At one year, the all-cause death rate was significantly lower in the TAVR group than the surgical group. Additionally, patients in the TAVR group had an absolute risk reduction of 4.9%. The researchers believed the TAVR’s less-invasive nature allows patients to mobilize and recover in as little as one week, which contributes to the survival benefit that occurred consistently across 9 subgroups, including age, sex, body mass index (BMI), hypertension, previous coronary artery bypass grafting (CABG), peripheral vascular disease, and diabetes.

Although the study was not designed to gauge stroke outcomes, the stroke rates were 13% and 9% in the surgery and TAVR groups, respectively.

The researchers concluded both TAVR systems will require long-term study to determine whether TAVR valves endure as long as those implanted surgically, which last around 20 years.

Researchers believe the less-invasive nature of transcatheter aortic-valve replacement systems allows patients to mobilize and recover in as little as one week, which contributes to the device's greater survival benefit compared to open-heart surgery.

Transcatheter Aortic-Valve Replacement Deemed Safer than Open-Heart Surgery

Deep brain stimulation (DBS) surgery represents a significant medical achievement for patients with Parkinson’s disease (PD) or other hyperkinetic disorders that are refractory to medication. Despite DBS’s generally positive history, patients often have preconceptions about the procedure, especially its risks.

 on DBS that appeared in the January 2014 issue of the 

, researchers from the Mischer Neuroscience Institute in Texas assessed the incidence of surgical complications both during and after DBS device implantation. Their study population consisted of 728 patients with movement disorders who underwent new DBS device implantation surgery by a single surgeon between 2002 and 2010.

Across 1,356 stereotactic procedures, the patients received 1,333 new DBS electrodes and 1,218 new internal pulse generators (IPGs) for the treatment of movement disorders. Sixty-two percent of study population had PD, while the remaining patients were treated for essential tremor (19.8%), dystonia (8,8%), mixed disease (4.1%), and other hyperkinetic movement disorders (5.2%)

Although severe intraoperative adverse events were rare, they included vasovagal response in 6 patients, hypotension in 2 patients, and seizure in 2 patients. Additionally, 4 patients experienced asymptomatic intracerebral hemorrhage (ICH), 25 had asymptomatic intraventricular hemorrhage, 8 experienced symptomatic ICH, and 3 suffered ischemic infarction. For 13 patients, those events were associated with hemiparesis and/or decreased consciousness.

Eighteen patients developed long-term complications that did not require additional surgery. Of that group, 8 reported hardware discomfort and 10 reported loss of desired effect.

Some patients experienced hardware-related complications that required surgical revision, including wound infections (13 patients), lead malposition and/or migration (13 patients), component fracture (10 patients), component malfunction (4 patients), and loss of effect (19 patients).

The study, which was one of the largest trials on DBS to date, documented that complications secondary to DBS surgery are rare. The authors emphasized the DBS’s relative safety and hoped it encourages more patients to consider the benefits of the procedure.

Despite the generally positive history of deep brain stimulation, patients often have preconceptions about the procedure, especially its risks.

Avoiding the Common Complications of Deep Brain Stimulation

Since 2002, the United States Preventive Services Task Force (USPSTF) has recommended preoperative psychological screening (PPS) for patients undergoing back surgery. The PPS starts with a 20- to 25-minute patient questionnaire and promotes follow-up with a longer assessment by a trained psychologist as needed.

To determine how many surgeons actually comply with this recommendation, researchers at Johns Hopkins University conducted a 

, the results of which appeared in the April 2014 issue of the 

The researchers invited 340 spine surgeons to complete an online survey, which was open between December 2010 and January 2011. In addition to basic demographic questions about the surgeons and their practices, the survey asked about the surgeon’s beliefs regarding the impact of psychological conditions on health and recovery, and use of the PPS.

Among the 110 respondents, 41 (37%) used PPS to screen for depression (100%) or anxiety (85%). More experienced surgeons (>15 years of practice), those with higher annual procedural volume (>200 back surgeries annually), and those who practiced independent of a university were more likely to administer PPS. Most spine surgeons did not use PPS routinely, despite indicating they were aware that psychological factors have serious repercussions on patients’ physical health and recovery. Most of the surgeons also said they did not employ an on-staff rehabilitation psychologist. Additionally, only 11 of 103 respondents routinely referred patients for PPS.

Thus, the survey reported only 10% of orthopedic surgeons and neurosurgeons follow professional guidelines recommending routine psychological screenings prior to major surgery for severe back and leg pain, even though more than 600,000 of those surgeries are performed in the US annually. The researchers pointed out that psychological conditions, especially anxiety and depression, can contribute to disabling back pain and poor health outcomes, including longer recuperation, delayed return to work, postsurgical complications, and post-discharge medication noncompliance.

“Our survey results show that surgeons and patients still have a long way to go in recognizing and appreciating how much psychological factors and mental health can impact the success of their back surgeries,” health services researcher and senior study investigator Richard Skolasky, ScD, said. “It may be necessary to delay surgery in order to first treat a patient’s depression or anxiety to minimize the likelihood of prolonged recuperation after their operation.”

The researchers were surprised that spine surgeons in private practices or community hospitals were more likely to administer psychological screening tests than their university-affiliated counterparts. 

Survey results show that surgeons still have a long way to go in recognizing how psychological factors can impact the success of back surgeries.

Most Surgeons Skip Routine Pre-op Psychological Screenings

Heart surgery patients can experience postoperative atrial fibrillation (PAF) after mitral valve surgery, cardiac bypass surgery, or both. As the complications of PAF include stroke and longer hospital stays, surgeons have spent decades searching for cost-effective ways to prevent and treat the condition.

Previous studies demonstrated an inverse association between PAF and betaâ€blocker use; however, that suggests PAF’s underlying etiology is related to excessive sympathetic discharge and catecholamines.

Now, researchers at East Carolina University’s Brody School of Medicine have identified monoamine oxidase (MAO) as a major determinate of PAF and detailed their findings in a 

 published in the March 2014 issue of the 

The researchers examined human heart tissue samples obtained from 244 patients who underwent cardiac surgery between 2010 and 2012. They assessed reactive oxygen species (ROS) generation from multiple sources in the cardiac tissue and examined total glutathione (GSHt), GSH-peroxidase (GPx), and GSH-reductase (GR).

“What we found is that the enzyme responsible for metabolizing epinephrine and dopamine, MAO, is a strong predictor of whether a person will have atrial fibrillation after heart surgery,” said Ethan Anderson, PhD, the study’s principal investigator.

The researchers determined that MAO and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase generated ROS at rates 10-fold greater than intact, 

Additionally, they determined MAO activity varied 50â€fold among patients. Those with the highest level of MAO activity were significantly more likely to develop PAF. GPx was also associated with PAF, but the relationship was not linear.

The authors concluded that atrial MAO activity is an independent predictor of PAF. Their findings also supported the current theory that PAF’s etiology originates in atrial myocardium redox imbalance, such as oxidative stress.

As the complications of postoperative atrial fibrillation include stroke and longer hospital stays, surgeons have spent decades searching for cost-effective ways to prevent and treat the condition.

One Step Closer to Identifying Post-op Atrial Fibrillation Causes, Prevention

Clinicians are often concerned about balancing the adequate treatment of acute postsurgical pain against adverse effects, persistent opioid use, and opioids’ contribution to the development of persistent pain. As a result, many surgeons would appreciate access to an assessment tool that could predict prolonged postoperative opioid use.

 published in the February 2014 issue of 

 described opioid-naïve patients’ rates of prolonged postoperative opioid use and identified the risk factors for it.

The study authors enrolled 39,140 opioid-naïve patients aged 66 years or older who underwent major elective surgery — including cardiac, intrathoracic, intra-abdominal, and pelvic procedures &mdash; at acute care hospitals in Ontario, Canada, between April 2003 and March 2010. Prolonged opioid use was defined as ongoing outpatient prescriptions for opioids for more than 90 days post-surgery.

Approximately half of the patients (49.2%) were discharged from the hospital with an opioid prescription. By 90 days after surgery, only 3.1% continued to receive opioids.

Those with a significantly higher risk of prolonged opioid use were typically younger, earned a lower household income, and had specific comorbidities, such as diabetes, heart failure, and pulmonary disease. Preoperative use of certain drugs — including benzodiazepines, selective serotonin reuptake inhibitors (SSRIs), and angiotensin converting enzyme (ACE) inhibitors &mdash; was also associated with prolonged opioid use. The researchers explained that the use of ACE inhibitors may prompt prescribers to avoid non-steroidal anti-inflammatory drugs (NSAIDs) because they may precipitate decompensated heart failure. Among those patients, prescribers may prefer opioids, instead.

The type of surgical procedure was also highly associated with prolonged opioid use. For example, open- and minimally-invasive thoracic procedures were twice as likely to end with prolonged opioid use than open radical prostatectomies. However, open- and minimally-invasive major gynecological procedures were associated with significantly lower risks compared to other surgeries.

Although the study could not prove that all identified associations are causal relations, the findings explained some long-term risks of opioid treatment in the postoperative setting. The results may also help surgeons direct appropriate interventions to specific patient subgroups.

A study published in BMJ explains the long-term risks of opioid treatment in the postoperative setting.

April 2014