Tag Archives: burns

Burn injuries, Catastrophic Injury, Experts

Defending the Pediatric Burn Case: How Knowing the Medical Literature and New Treatment Modalities Can Help Control Damages

Surgeons discussing computed tomography (CT) scans in operating theatre

Introduction

Most seasoned defense attorneys are well aware of the three subjects that often tend to cause far higher-than-expected verdicts: burns, kids, and cancer.  In this article we will address the danger of situations where there is not only a child, but the child is severely burned.

In prior posts we addressed burn classification, conventional treatment modalities, and aspects of expected outcomes.  We will not repeat that information here but instead address some general mortality statistics and where children, specifically those age six and younger, fit in.  We will also address experimental and new therapies for children, as described in the recent literature, including the use of virtual reality, albuterol inhalants, and aerosolized Heparin/Acetylcystine therapies.  All of these therapies have been shown to lower mortality rates in children.

Regardless of the burn mechanism, defending a pediatric burn case, especially if it was fatal, can be extremely difficult.  Juries tend to be very sensitive to burn injuries, especially in cases involving children.  Therefore, the product liability or aviation defense lawyer must have an in-depth understanding of the mechanics of burn injuries and available treatment options, particularly in those cases where inhalation injury is a component.  Both an aircraft cabin and a home are confined spaces that can be filled with fatal levels of smoke, sometimes within seconds.  Given these considerations, it is essential that the defense attorney be thoroughly prepared, armed with both knowledge and empathy.

Statistical Overview of Burn Injuries

According to the National Burn Repository,[1] which gathers and analyzes statistical data from burn centers throughout the United States and Canada, there were 126,000 hospital admissions for burns from 1995 – 2005.  The mean burn size was 13.4 percent total body surface area (TBSA) with sixty-two percent of the full thickness burns covering less than ten percent TBSA.  Sixty-one percent of patients were transferred to another hospital for a higher level of care.  Six and one-half percent of admissions had inhalation injuries.  The data also show that the patients were seventy percent male with a mean age of 33 years.  Flame and scald burns accounted for seventy-eight percent of all burn injuries.

The prognostic burn index, a sum of the patient’s age and percentage of TBSA burn, was used as a gauge for patient mortality for many years.  This index suggested that by taking into consideration the patient’s age and the size of their full thickness TBSA burn, and adding twenty percent for inhalation, the patient’s mortality probability could be predicted.[2]  Advances in early excision of burn eschar,[3] skin grafting, early enteral feeding,[4] and wound closure with advanced techniques (skin substitutes) have altered the simple mathematical calculation.[5]  Patients with a prognostic burn index of 90 – 100 now have a mortality rate in the 50 – 70% range with poorer outcomes at both extremes of age.[6]

The Importance of Pediatric Treatment in Cases Involving Inhalation Burns 

As noted above, mortality rates are higher in pediatric patients.  Smoke inhalation injury continues to be implicated as the leading cause of death in persons with burn injuries.  Smoke inhalation injury has a reported mortality of 20 – 80%.[7]  This is also supported by the addition of 20% traditionally added to the prognostic burn index.

In smoke inhalation injury, there is a destruction of the ciliated epithelium[8] that lines the tracheobronchial tree.  Casts[9] from these cells cause upper-airway destruction, and this leads to obstruction, causing pulmonary failure.  In one recent study, the reduction in mortality in pediatric patients with inhalation injuries placed on a regimen of aerosolized heparin[10] and acetylcystine[11] was tested.[12]  Forty-seven children, acting against forty-three controls, received 5000 units of heparin and 3 ml of a 20% solution of acetylcystine aerosolized every four hours for the first seven days of injury.  All patients were extubated when they were able to maintain spontaneous oxygen levels.  The number of patients requiring re-intubation for successive pulmonary failure was recorded, as was mortality.

The results indicate a significant decrease in re-intubation rates, incidence of atelectasis,[13] and mortality for patients treated with the regimen of heparin and acetylcystine when compared with the controls.  Heparin/acetylcystine nebulization in children with massive burn and smoke inhalation injuries results in a significant decrease in incidence of re-intubation for progressive pulmonary failure and a reduction in mortality.

The Use of Virtual Reality For Acute Pain Management in Pediatric Burn Patients

In one experimental case, virtual reality was tested for pain management.[14]  Managing high pain levels associated with pediatric burns can result in a decreased reliance on opioid medications and can potentially minimize future risk of developing psychiatric problems.  During the study, hospitalized patients over the age of six and without facial burns were selected.  A lightweight helmet with binocular display provided patients with a Virtual Reality (VR) experience during acute pain procedures such as wound care or therapy.  Pain levels were assessed using the Faces Pain Scale (FPS).[15] Constitutional signs and symptoms, opioid medication usage, as well as nursing and family member assessments of pain were also recorded.  VR provided a three-dimensional computer-simulated environment where patients could see, hear, and interact with objects displayed in the virtual world.

Preliminary results suggested at least a 20% decrease on FPS during VR intervention.  Pediatric patients report an increased tolerance to exposed dressing sites during VR.  It remains unknown which patient factors (age, sex, characteristics of the burn, background pain level, etc.) are predictive of effective pain management with VR.

Conclusion

Olson Brooksby has defended many product liability and aviation cases where the resulting injury was a serious, sometimes fatal, burn.  From a defense perspective, such cases pose difficulties if defense counsel is not prepared to skillfully handle the cross examination of the treating burn physician.  The best way to do so is to be familiar with the prevailing treatment methods and the relevant literature.  Conversance with the literature will provide a working understanding of the techniques that were available to the treatment team to minimize the pediatric burn patient’s pain and increase the likelihood of survival.

 

[1] Miller, S.F.M., et al., National Burn Repository, 2005, American Burn Association: Chicago, IL. P. 1-51.

[2] Grunwald, T.B. and Garner, W.L. Acute Burns. University of Southern California; Los Angeles County + USC Burn Center, Los Angeles, California.

[3] Dead matter cast off the surface of the skin after a burn.

[4] Tubal feeding through the intestine.

[5] Rose, D.D. and E.B. Jordan, Perioperative management of burn patients.  Aorn J, 1999. 69(6): p. 1211-22; quiz 1223-30.

[6] N., K. Aoki, and M. Yamazaki, Recent advances in the management of severely burned patients.  Nippon Geka Gakkai Zasshi, 1999. 100(7): p. 424-9.

[7] Thompson PB, Herndon DN, Taber DL, et al.  Effects of mortality of inhalation injury. J. Trauma 1986; 26:163-5.

[8] Threadlike projections from the free surface of epithelial cells such as those lining the trachea, or bronchi.  The propel or sweep materials, such as mucus or dust across a surface such as the respiratory tract.  Taber’s Cyclopedic Medical Dictionary, 19th Ed.. 2001. Venes. D., Ed., F.A. Davis Co., Philadelphia.

[9] Pliable or fibrous material shed in various  pathological conditions, the product of effusion.  It is molded to the shape of the part in which it has been accumulated, i.e., bronchial or tracheal casts.  Taber’s Cyclopedic Medical Dictionary, 19th Ed.. 2001. Venes. D., Ed., F.A. Davis Co., Philadelphia.

[10] Heparin is an aparenteral anticoagulant drug with a faster effect than warfarin or its derivatives.  It is composed of polysaccharides that inhibit coagulation by forming an antithrombin. An antithrombin is anything that prevents action on the thrombin.  The Thrombin is an enzyme formed in coagulating blood which reacts with soluble fibrinogen to form a blood clot.  Taber’s Cyclopedic Medical Dictionary, 19th Ed.. 2001. Venes. D., Ed., F.A. Davis Co., Philadelphia.

[11] Acetylcystine is a chemical substance that, when nebulized and inhaled, liquefies mucus and pus.  Taber’s Cyclopedic Medical Dictionary, 19th Ed.. 2001. Venes. D., Ed., F.A. Davis Co., Philadelphia.

[12] M.H. Desai, MD, R. Micak, RRT, RCP, J. Richardson, RCP, RRT, R. Nichols, MD, and D.N. Herndon, MD.  Reduction in Mortality in Pediatric Patients with Inhalation Injury with Aerosolized Heparin/Acetylcystiine Therapy.  University of Texas Medical Branch and Shriners Burns Institute, Galveston.  American Burn Association, 1998.

[13] Collapse of part (or, less commonly, all) of a lung.

[14] Minassian, A PhD; Kotay, A MS; Perry, W PhD; Tenenhaus, M MD, FACS; Potenza, B M. MD, FACS.  The Use of Virtual Reality for Acute Pain Management in Pediatric Burn Patients.  University of California San Diego, The American Burn Association, 2006.

[15] The Faces Pain Scale, also known as the Wong-Baker FACES Pain Rating Scale, is intended for children over three years of age.  It provides a series of six drawn facial expressions with an associated numerical value from zero through 5 representing the associated pain.  Hockenberry MJ, Wilson D:  Wong’s Essentials of Pediatric Nursing, 8th Edition. St. Louis:  2009: Mosby.

 

Aviation, aviation attorney, aviation attorney, aviation, aviation law, aviation lawyer, aviation law, aviation lawyer, Manufacturing, Metals, Personal Injury

Turbine Engine Hot Section Manufacturing: Complex Metallurgy and Dangerous Work Environments

Turbine engine hot section manufacturing is a complex industry that involves risk of serious injury and an adherence to safety rules and best practices.

There is a common maxim that two technologies liberated the modern world: the automatic washing machine and the jet engine.  When RAF Lieutenant Frank Whittle received an English patent on the basic design for the modern jet engine in 1930 (the first flight was not until 1941), he probably could not have imagined the changes that would occur, in materials, complexity, and performance capability.

Today’s commercial jet engines have as many as 25,000 parts.  They are up to eleven feet in diameter and twelve feet long.  The engines can weigh more than 10,000 pounds and produce 100,000 pounds of thrust.  Even the engine on a fully tested and approved design may take two years to assemble.  A super-jumbo jet can carry 500-800 passengers, depending on configuration, and have a take-off weight of 1.2 million pounds.

Section I will provide a basic overview of the production and metallurgical complexities associated with the manufacture of some hot section components.  Section II will address a unique aspect of jet hot section manufacturing.  Specifically, the complex and exacting standards required to avoid catastrophic in-flight aviation accidents also require the most disciplined adherence to best practices for safety to avoid catastrophic occupational injury, particularly burns, in high temperature work environments.  Section III will briefly discuss the catastrophic burn injuries that result from failure to follow exacting safety precautions.

Section I:  The Hot Section

At the front of the engine, a fan drives air into the engine’s first compartment, the compressor, a space approximately 20 times smaller than the first stage of the compressor.   As the air leaves the high-pressure compressor and enters the combustor, it mixes with fuel and is burned.  As the gas is combusted and expands, some gas passes through the exhaust and some is rerouted to the engine’s turbine (a set of fans that rotate compressor blades).  The turbine extracts energy from the ultra-hot gases to power the compressor shaft and generate power.

Because the turbine is subject to such incredible heat, labyrinthine airways in the turbine blades allow cool air to pass through them to cool the turbine.  With the cooling mechanism of the airstream, the turbine can function in gas streams where the temperature is higher than the melting point of the alloy from which the turbine is made.

Titanium, purified to aviation specifications in the 1950s, is used for the most critical components of the “hot section” such as the combustion chamber and turbine.  The hardness of titanium is difficult to work with, but it is resistant to extreme heat.  It is often alloyed with other metals such as nickel and aluminum for high strength/weight ratios.

Hot Section Component Manufacturing

The intake fan.  The fan must be strong so it does not fracture if large birds or debris are sucked in.  It is made of a titanium alloy.  Each fan blade consists of two skins produced by shaping molten titanium in a hot press.  Each blade skin is welded to a mate, with a hollow cavity in the center being filled with titanium honeycomb.

The compressor disc. This is a solid core, resembling a notched wheel, to which the compressor blades are attached.  It must be free of even minute imperfections, since these could cause creeping or develop into fractures under the tremendous stress of engine operation.  Historically machined, compressor discs are now manufactured through a process called powder metallurgy, which consists of pouring molten metal onto a rapidly rotating turntable that breaks the molten metal into millions of microscopic droplets that are flung back up almost immediately, due to the table’s spinning.  As they leave the turntable, the droplets’ temperature plummets by 2120 degrees Fahrenheit (1000 degrees Celsius) in half a second, causing them to solidify and form a very fine metal powder, which solidifies too quickly to absorb impurities.  The powder is packed into a forming case and vibrated in a vacuum to remove air.  The case is then sealed and heated, under 25,000 pounds of pressure per square, inch into a disc.

Compressor blades.  These blades are still formed by traditional methods of casting.  Alloy is poured into a ceramic mold, heated in a furnace, and cooled.  The mold is broken and blades are machined to final shape, often to exacting tolerances on the order of 7 microns.

Combustion chambers.  Combustion chambers blend air and fuel in small spaces for long periods of time at incredible temperatures.  Titanium is alloyed (to increase ductility) and then heated to liquid before being poured into several complex segment molds.  The segments are welded together after cooling and removal.

The turbine disc and blades.  The turbine disc is formed by the same powder metallurgy used to create the compressor disc.  However, turbine blades are subjected to even greater stress due to the intense heat of the combustor.  Copies of the blades are formed by pouring wax into metal molds.  Once set, the wax shape is removed and immersed in a ceramic slurry bath, forming a ceramic coating.  Each cluster of shapes is heated to harden the ceramic and melt the wax.  Molten metal is then poured into the hollow left by the melted wax.

The metal grains of the blades are then aligned parallel to the blade by directional solidifying, which is important due to the blade stresses.  If the grains are aligned correctly, the blade is much less likely to fracture.  The solidifying process takes place in computer-controlled ovens to precise specifications.  Parallel lines of tiny holes are formed to supplement internal cooling passageways, either by a small laser beam or by spark erosion, where sparks are carefully allowed to eat holes in the blade.

Turbine blades are subject to temperatures of around 2,500 degrees Fahrenheit (1,370 Celsius.  At such temperatures, creep, corrosion, and fatigue failures are all possible.  Thermal barrier coatings, such as aluminide coatings developed during the 1970s, facilitated cooling.  Ceramic coatings developed during the 1980s improved blade capability by about 200 degrees F. and nearly doubled blade life.

Modern turbine blades often use nickel-based superalloys that incorporate chromium, cobalt, and rhenium.  Some superalloys incorporate crystal technology.  Nimonic is another super low-creep superalloy used in turbine blades.  Titanium aluminide, a chemical compound with excellent mechanical properties at elevated temperatures, may replace Ni based superalloys in turbine blades.  GE uses titanium aluminide on low pressure turbine blades on the GEnx engine powering Boeing 787s.  The blades are cast by Precision Castparts Corp.

Exhaust system.  The inner duct and afterburners are molded from titanium, while the outer duct and nacelle are formed from Kevlar, with all components welded into a subassembly.

Section II.  Defects in Both Hot Section Components and Safety Procedures Can Result in Catastrophic Injuries

An imperfection in the hot section, which results, for example, in a blade fracture during flight, or excessive creep, may result in an uncontrolled engine failure, among other catastrophic inflight mishaps, putting lives at risk.  In an interesting corollary, unique to very few manufacturing settings, adherence to the safest manufacturing processes will minimize both product defects and worker injuries, primarily serious burns.

Few Things Drive Higher Verdicts, Workers Compensation Costs, or Settlements, Than Burns

In those industries where “serious large burns” can arbitrarily be defined as full-thickness burns over 20% or more of the total body surface area (TBSA), the location of the burns and the relative availability of certain types of grafts can be outcome determinative and correlate directly with litigation risk, settlements, and verdicts. Most problematic are 4th degree burns to the hands or face, which can never, ever, be fully repaired with current surgical technology or therapeutic treatments.

Skin Graft Classification

There are two common types of skin grafts.  A split-thickness graft (STSG), or mesh graft, includes the epidermis and part of the dermis.  A mesher makes apertures in the graft, allowing it to expand approximately 9 times its original size.

Alternatively, a full thickness skin graft, or sheet graft, which involves pitching and cutting away skin from the donor section, is more risky in terms of rejection.  Yet counter-intuitively, this method leaves a scar only on the donor section, heals more quickly, and is less painful than split-thickness grafting.  This type of grafting, sheet grafting, must be used for hands and faces/heads where graft contraction must be minimized, and it is therefore extremely difficult to achieve in large TBSA burns.

Remedies

Although workers compensation laws will generally bar litigation by workers against their employers, in cases where the exclusive remedy provision of workers compensation does not apply, it is not uncommon in the United States to see burn verdicts or settlements in the millions or even tens of millions of dollars.  Mandatory PPE and best safety practices for dealing with ultra-high temperature work environments can minimize injuries, although the practical reality is that elimination of such injuries remains an aspirational goal.