Thoracic damage control surgery

A estratégia de controle de danos surgiu na campanha da marinha aliada durante a II Grande Guerra. Observou-se que em navios gravemente atingidos durante o combate, havia menores baixas e naufrágios quando os esforços se concentravam em extinguir incêndios e manter a embarcação em funcionamento, batendo em retirada acobertada por outras naves da esquadra amiga, ao invés de continuar combatendo. Já em território amigo, nos estaleiros, longe de área hostil, procediam-se aos reparos definitivos. O conceito no campo da cirurgia do trauma surgiu nos anos de 1990, para doentes em vigência da quase exaustão das suas reservas fisiológicas, com manifestação de hipotermia, acidose metabólica e coagulopatia (Tríade mortal). Adotou-se a estratégia de se fazer um mínimo possível (controle de sangramento e contaminação) no menor espaço de tempo, sendo então o doente encaminhado à unidade de terapia intensiva para ser aquecido e compensado por tempo mais ou menos definido e, somente então, ter suas lesões definitivamente corrigidas em ambiente cirúrgico. Definiu-se assim as três fases pelas quais os sobreviventes passariam até sua recuperação, acompanhados por equipe multidisciplinar, sempre encabeçada pelo cirurgião1,2. Pouco tempo depois das primeiras publicações de “Damage control”, surgiu o conceito da chamada fase “0”, em que antes mesmo de se iniciar a cirurgia de controle de danos (Fase 1), o cirurgião deveria ter em mente quais os possíveis candidatos a este tipo de terapêutica, ainda em ambiente pré-hospitalar e na sala de emergência. Isto é, ter como objetivo o “controle das lesões” antes que a tríade letal já tenha se instalado e quando as chances de sobrevivência são muito reduzidas. A cirurgia assim “abreviada”, sem a correção definitiva das lesões, implica num aumento de morbidade em troco da diminuição da mortalidade3. No traumatismo torácico, em uma fração de doentes, poderá ser empregada esta estratégia, já que a maioria é tratada por medidas simples como a complementação com oxigenoterapia e pela drenagem pleural, como medidas eficazes e definitivas. Alguns doentes, no entanto, evoluem com sangramento contínuo pelo dreno, com choque mantido apesar das manobras de reanimação, com fuga aérea que não permite a ventilação ou com lesão vascular ou esofágica, que constituem indicações clássicas de intervenção. Estas situações podem estar associadas à lesões de outros compartimentos corporais, ajudando a consumir as reservas fisiológicas do traumatizado. Nestes indivíduos ou quando o tempo cirúrgico e o sangramento se estendem, o cirurgião deve ter o conhecimento da cirurgia de controles de danos torácico.


INTRODUCTION
T he damage control strategy emerged in the Allied navy campaign during World War II.It was observed that in ships severely hit during the fighting, there were minor casualties and shipwrecks where efforts focused on extinguishing fires and keeping the boat running, retreating while covered by other friendly fleet ships, rather than continuing to fight.Then, in friendly territory, on construction sites, far from hostile areas, definitive repairs were held.
The concept in the field of trauma surgery emerged in the nineties, for patients in near exhaustion of their physiological reserves, with manifestation of hypothermia, metabolic acidosis and coagulopathy ("deadly triad").The adopted strategy consisted in making the minimum necessary (bleeding and contamination control) in the shortest time, the patients being referred to the intensive care unit to be heated and stabilized, and only then, have their injuries definitely repaired in the operating environment.There were thus three defined stages through which the survivors would pass before recovery, accompanied by a multidisciplinary team, always led by surgeon 1,2 .
Shortly after the first Damage Control publications, arose the concept of the so-called phase 0, wherein even before starting the damage control operation (Phase 1), the surgeon should have in mind which patients would be candidates for this type of therapy, even in the pre hospital setting and emergency room.That is, aim to "control the damage" before the lethal triad ensues and when the chances of survival are very low.The so shortened surgery, without definitive correction of injuries, implies an increase in morbidity in exchange for decreased mortality 3 .
In thoracic trauma, most patients are treated by simple measures, such as supplementation with oxygen therapy and pleural drainage as effective and definitive measures.However, in a fraction of patients, this strategy can be employed.Some patients evolve with continuous bleeding from the drain with maintained shock despite resuscitation, with air leak impairing ventilation or with vascular or esophageal injury, which are classical indications for intervention.These situations may be associated with injuries to other body compartments, adding in the consumption of the traumatized physiological reserves.In these individuals, or when the surgical time and bleeding extend, the surgeon must know thoracic damage control surgery.

Review Article
The damage control surgery came up with the philosophy of applying essential maneuvers to control bleeding and abdominal contamination in trauma patients who are within the limits of their physiological reserves.This concept was extended to thoracic injuries, where relatively simple maneuvers can shorten operative time of in extremis patients.This article aims to revise the various damage control techniques in thoracic organs that must be known to the surgeon engaged in emergency care.

Gonçalves
Thoracic damage control surgery required already in the emergency room.Despite the high mortality rate associated with this procedure, due to the extreme patient's conditions, this type of approach has indications and set goals.The emergency thoracotomy may represent the biggest paradigm of damage control in surgery, as it involves aggressive, fast and often temporary control of lesions that are consuming the patient's physiological reserves, in an inhospitable environment (emergency room).Then the patient is sent to the operating room, and finally, to the most appropriate environment, the ICU, for compensation of acidosis and coagulopathy, and where he/she will be monitored, heated and reanimated.
The objectives of an emergency thoracotomy include: cardiac tamponade relief that is causing diastolic restriction, control of heart wound or exsanguinantion due to vascular injury, descending aortic clamping to increase coronary and brain blood flow, internal cardiac compressions and occlusion of pulmonary hilum to reduce possibility of air embolism and decreased bleeding in severe lung injury 4 .
In ventricular wounds, the temporary initial control should be performed by digital occlusion or introduction of a Foley catheter through the wound and inflation of its cuff 5 .The ventricular suture must be performed with nonabsorbable suture and vascular needle (4-0 polypropylene) in "U" or "Halsted"-shape stitches.In injuries close to the coronary arteries, the stitches must be passed beneath these structures.In the event of coronary lesions, distal lesions should be treated with ligation.Proximal lesions display high mortality, since most often myocardial infarction is already installed.These require a cardiovascular surgeon for correction and extracorporeal circulation may be necessary, which in most cases is impractical for this type of patient.The option then is ligation, with high mortality rates 6 .
Atrial wounds have higher friability, demanding a more careful suture.Their initial control can be accomplished with lateral application of a vascular clamp, and then holding the repair with continuous nonabsorbable suture.
Some maneuvers can be employed in an attempt to stabilize the cardiac movements during cardiorraphy.Among these, there are the application of stitches in the heart apex, which are then tractioned, or the application of a Satinsky vascular clamp in the right ventricular angle with gentle traction to stabilize the movements and get a more accurate suture 7 .
In recent years there have descriptions of the use of skin staplers for primary control of ventricular lesions in the emergency room with good results 8 (Figure 1).Extensive cardiac lacerations may require interruption of blood flow, but this tactic should be the last resort, as it will reduce and even stop the heartbeats, and will often be difficult to restart them.There are at least two maneuvers for this purpose: the first is to clamp the superior vena cava and the inferior vena cava and thereby reduce the preload, with cardiac emptying and Gonçalves Thoracic damage control surgery arrest; the second technique is done by a right atrium manual compression against the ventricular mass 9 .The principle is the same as the first technique, as it will lead to decreased blood flow and eventually cardiac arrest.After these maneuvers, suturing will be possible for a few minutes.Following suture, the heart must be heated with saline while performing direct compressions.At the moment that there is fibrillation, defibrillation can be applied directly to the heart with energy up to 30-50 Joules.

LUNG
The surgeon will hardly come across a lung injury where there is difficult bleeding control.This is mainly due to two factors: the pulmonary vasculature houses a low-pressure system and the lung parenchyma is rich in thromboplastin.However, there are situations where bleeding may be profuse, both due to the anatomy where the lesion is located, and to the patient's metabolic exhaustion.Among these types of injury, we can mention the tunnelling or transfixing lesions that do not reach the hilum, the hilar lesions, and the diffuse parenchymal lesions.
Tunnelling or transfixing injuries: patients who have this type of injury possibly have bleeding from the inlet and outlet of the lung.Simple closure of these injuries would imply a large lung dissecting hematoma or infection in the postoperative period, with lung abscess formation.The technical solution for this type of injury occurs through pulmonary tractotomy.It consists in applying two long vascular clamps or parts of a linear cutting stapler through the "path" of the lesion and sectioning the parenchymal bridge between the clamps, which exposes the interior of injury to the outside, and then holding selective hemostasis and aerostasis inside the wound.When using clamps, aerostasis and hemostasis are terminated with a running absorbable suture over the clamps, which is unnecessary when using the stapler 10,11 (Figure 2).Peripheral bleeding and air-leaking lesions may be quickly resected using the mechanical suture 12 .
Hilar injuries: in this type of injury, often lethal, the victim is extremely ill on admission to the emergency room.It classically presents with profuse bleeding into the pleural cavity or pericardial tamponade, if the injury is within the pericardial sac, which in both cases will require an emergency thoracotomy.The primary control of hilar bleeding should be manual, through the fastening between the thumb and index finger, followed  Venous transection imply corresponding lobectomy, while the arterial lesion will usually require pneumonectomy, with a high degree of mortality.When this is unavoidable, it can be quickly made using a stapler with a vascular load 13,14 .The technique consists in applying the stapler as distal as possible so that one can perform a reinforcement suture, and after firing, holding the stump with two Allis   One should keep in mind which vessels could be ligated 17 .
Theoretically, one can perform ligation of all thoracic venous vessels, with the exception of the venae cavae; amongst the arterial branches, the ligation of the innominate artery can result in extensive stroke.The subclavian arteries, however, ultimately may be ligated because they have a rich collateral circulation network in the shoulder girdle.An alternative to arterial ligation is construction of an intravascular shunt (Figure 1) through a silicone conduit tied to the arterial ends, particularly in the subclavian ones.In the event of a stable mediastinal or extrapleural hematoma due to a greater vascular injury, the conduct may be initially conservative in a seriously injured patient in whom a thoracic operation would involve major trauma and bleeding, consuming the last physiologic reserves.The classic case to illustrate this is a patient with multi-systemic trauma and a contained injury in the descending aorta.This patient may benefit from a conservative approach, with resolution of the other injuries (brain, orthopedic and abdominal), and only then be submitted to aortic endovascular treatment 18 .

ESOPHAGUS
Early diagnosed lesions have been treated by primary surgical synthesis associated with nasogastric catheterization and pleural drainage.In iatrogenic perforation during endoscopic procedures, there have descriptions of endoscopic treatments with clipping, positioning of esophageal stents, endoscopic suturing and even conservative treatment for minor injuries in stable patients 19,20 .
However, injuries of the thoracic esophagus from external causes (i.e.stabbing of gunshot wounds) are often silent lesions that go unnoticed, with late diagnosis performed by pleural effusion and by sepsis installed due to associated mediastinitis.In these critically ill patients with low physiological reserve for arepair attempt (with high rates of fistula), or to perform esophagectomy (high mortality), the choices left are the bypass and exclusion,through cervical esophagostomy, associated with gastrostomy and exteriorized through the skin, thus creating a controlled fistula 21 .A nasogastric catheter may be passed into the tube for subsequent feeding.An abundant pleural drainage should be associated with this procedure (Figure 4).Gonçalves Thoracic damage control surgery repair the injuries permanently.The other indication is in the event of an anterolateral thoracotomy or sternotomy where, after opening the pericardium, the heart is very dilated and the closing of the wall will restrict the heartbeats 23,24 (Figure 5).

Situations
The temporary closure technique may be performed only by approximation of the skin or, in extreme cases where there is still cardio-respiratory restriction, by suturing a Smarchtape to the skin.One can also use an open urine collection bag (similar to the "Bogota bag" principle), or placing packs, covered by adhesive surgical drapes in the skin, like steri-drape, with application of vacuum (VAC -vacuum-assisted closure-technique), in particular in infected wounds 25,26 (Figure 6).The final synthesis of the chest wall may take several days to complete.
In conclusion, we believe that the general surgeon who serves in the emergency should know the thoracic damage control techniques, so as they can serve as therapeutic management tools in critically ill patients.
Most patients who have cardiac injuries die at the trauma scene.Of those who live to arrive at the emergency room, penetrating trauma is the most common and often the patient is unstable, a thoracotomy being 1 -Faculty of Medical Sciences of the São Paulo Holy Home, Department of Surgery -São Paulo -SP -Brazil

Figure 1 .
Figure 1.Aspects of cardiac and vascular damagecontrol.A) Cardiac wound synthesis with metal clips through an left anterolateral thoracotomy;B) Positioning ofendoarterial shunt with a 22F chest tube segment in a descending aortic injury.

Figure 2 .
Figure 2. Aspects of lung damage control: A) Clamping of the pulmonary hilum after release of the pulmonary ligament; B) Tractotomy with stapler in tunnelling, bleeding lesion in the left upper lobe; C) Selective ligation after lung tractotomy; D) Left pneumonectomy with stapler.E) Justa-pericardial staples line; F) Specimen from pneumonectomy, with the line of staples on the left hilum (details in the text).

Gonçalves
Thoracic damage control surgery by pulmonary mobilization by section of the pulmonary ligament and only then the placement of a large vascular clamp around the hilum 13 .This type of patient generally tolerates badly this maneuver, developing severe right ventricular dysfunction, which requires rapid diagnosis of the extent to which the hilum was affected.Partial arterial or venous lesions should be treated with lateral sutures.
clamps.Only then one opens the stapler and completes hemostasis with nonabsorbable suture.Some injuries are central, but spare the pulmonary hilum.In those situations where bleeding is profuse and air embolization may occur through some larger caliber pulmonary vein, one can use Lung Twist Maneuver for the rapid control of the wound.This consists in quickly releasing the pulmonary ligament and rotating the lung 180 degrees around the hilum.With this done the hilar vessels undergo a "sprain", immediately stopping the bleeding15 .Diffuse lung injuries: sometimes the lungs may be diffusely bruised or lacerated and the patient already has coagulopathy.In such dramatic situations, the options are pneumonectomy, which can be devastating for the patient.Alternatively, one can set up a selective ventilation of the non-traumatized lung, when possible, and packaging of the traumatized one16 , a technique that has emerged for control of extensive lesions of the liver parenchyma, an organ that has also an extensive, low-pressure vascular network.One should take care that packs do not cause cardiac diastolic restriction or mediastinal shift, which would lead to a low cardiac output.Packs are to be removed after the correction of coagulopathy (Figure3).

Figure 3 .
Figure 3. Chest radiography in the postoperative period of thoracic packaging for coagulopathy.Note the presence of radiopaque stripes of seven packs in the left hemithorax.

Figure 4 .
Figure 4. A) Positioning of a large caliber Kher drain in an esophageal injury.The schematic detail depicts the approaching of the lesion, the passing of nasal-enteral feeding tubes inside the "T" drain and the fixation with absorbable sutures in the diaphragm; B) Exteriorization of the Kherdrain through the chest wall

Figure 5 .
Figure 5. A) Thoracic Packing after sternotomy and coagulopathy.After placing packs in the mediastinum and sternum, a suction drain was placed and adhesive fields applied to seal the dressing (VAC technique); B) Mediastinal appearance with firm clots after the patient homeostasis restoration.
involving damage control in the chest wall can be divided into control of parietal bleeding and temporary closure of the chest wall.One of the most common causes of review and re-operating of the thoracic cavity is in a parietal bleeding vessel.Intercostal and internal thoracicarteries havetheir flow greatly diminished in a patient with hypovolemic shock.However, when the individual returns to the hemodynamically normal state, these vessels can reach a flow rate of 300ml per minute.Hence, the cautious ligature of these vessels becomes an important part in the first approach.Sometimes an intercostal vessel may present bleeding at the time of surgical exploration and, after sectioned, retract and become difficult to ligate.The options in this case are: "U" stitches parallel to the ribs; stitches circulating the entire rib and intercostal region into two segments and piercing of the wall through the bleeding point, and positioning of a catheter balloon (Foley or Fogarty) and fixing it to the skin, leaving it for a few days until the thrombosis of the affected vessel.In multiple traumato the ribs and thoracic wall, in which there is diffuse bleeding, one can apply thoracic packaging22 .The temporary closure (abbreviated thoracotomy) is indicated in two situations.The first one, in which there is temporary control of the injuries, with coagulopathy and requiring rapprochement to remove packs or to

Figure 6 .
Figure 6.A) Infected pleural and mediastinal wound; B) Vacuum dressing aspect with sponges, suction drain and adhesive drape; C) Evolution of the wound with sanitation of the pleural space and development of granulation tissue; D) Final phase of wound evolution, with obliteration of the pleural space and exuberant granulationtissue; after this phase a skin flap was performed, with satisfactory functional and aesthetic result.