Treatment of the flail chest initially follows the principles of advanced trauma life support. Further treatment includes:

- Good pain management includes intercostal blocks and avoiding opioid pain medication as much as possible. This allows much better ventilation, with improved tidal volume, and increased blood oxygenation.

- Positive pressure ventilation, meticulously adjusting the ventilator settings to avoid pulmonary barotrauma.

- Chest tubes as required.

- Adjustment of position to make the person most comfortable and provide relief of pain.

- Aggressive pulmonary toilet

Surgical fixation can help in significantly reducing the duration of ventilatory support and in conserving the pulmonary function.

A person may be intubated with a double lumen tracheal tube. In a double lumen endotracheal tube, each lumen may be connected to a different ventilator. Usually one side of the chest is affected more than the other, so each lung may require drastically different pressures and flows to adequately ventilate.

In order to begin a rehabilitation program for a flail chest it is important to treat the person's pain so they are able to perform the proper exercises. Due the underlying conditions that the flail segment has caused onto the respiratory system, chest physiotherapy is important to reduce further complications. Proper positioning of the body is key, including postural alignment for proper drainage of mucous secretions. The therapy will consist of a variety of postural positioning and changes in order to increase normal breathing. Along with postural repositioning, a variety of breathing exercises are also very important in order to allow the chest wall to reposition itself back to normal conditions. Breathing exercises will also include coughing procedures. Furthermore, range of motion exercises are given to reduce the atrophy of the musculature. With progression, resistance exercises are added to the regimen to the shoulder and arm of the side containing the injury. Moreover, trunk exercises will be introduced while sitting and will progress to during standing.

Hip flexion exercises can be done to expand the thorax. This is done by lying supine on a flat surface, flexing the knees and hips and bringing them in toward the chest. The knees should come in toward the chest while the person inhales, and exhale when the knees are lowered. This exercise can be done in 3 sets of 6-8 repetitions with a pause in between sets. The person should always make sure to maintain controlled breaths.

Eventually, the person will be progressed to walking and posture correction while walking. Before, the person is discharged from the hospital the person should be able to perform mobility exercises to the core and should have attained good posture.

Treatment of TBI varies based on the location and severity of injury and whether the patient is stable or having trouble breathing, but ensuring that the airway is patent so that the patient can breathe is always of paramount importance. Ensuring an open airway and adequate ventilation may be difficult in people with TBI. Intubation, one method to secure the airway, may be used to bypass a disruption in the airway in order to send air to the lungs. If necessary, a tube can be placed into the uninjured bronchus, and a single lung can be ventilated. If there is a penetrating injury to the neck through which air is escaping, the trachea may be intubated through the wound. Multiple unsuccessful attempts at conventional (direct) laryngoscopy may threaten the airway, so alternative techniques to visualize the airway, such as fiberoptic or video laryngoscopy, may be employed to facilitate tracheal intubation. If the upper trachea is injured, an incision can be made in the trachea (tracheotomy) or the cricothyroid membrane (cricothyrotomy, or cricothyroidotomy) in order to ensure an open airway. However, cricothyrotomy may not be useful if the trachea is lacerated below the site of the artificial airway. Tracheotomy is used sparingly because it can cause complications such as infections and narrowing of the trachea and larynx. When it is impossible to establish a sufficient airway, or when complicated surgery must be performed, cardiopulmonary bypass may be used—blood is pumped out of the body, oxygenated by a machine, and pumped back in. If a pneumothorax occurs, a chest tube may be inserted into the pleural cavity to remove the air.

People with TBI are provided with supplemental oxygen and may need mechanical ventilation. Employment of certain measures such as Positive end-expiratory pressure (PEEP) and ventilation at higher-than-normal pressures may be helpful in maintaining adequate oxygenation. However, such measures can also increase leakage of air through a tear, and can stress the sutures in a tear that has been surgically repaired; therefore the lowest possible airway pressures that still maintain oxygenation are typically used. Mechanical ventilation can also cause pulmonary barotrauma when high pressure is required to ventilate the lungs. Techniques such as pulmonary toilet (removal of secretions), fluid management, and treatment of pneumonia are employed to improve pulmonary compliance (the elasticity of the lungs).

While TBI may be managed without surgery, surgical repair of the tear is considered standard in the treatment of most TBI. It is required if a tear interferes with ventilation; if mediastinitis (inflammation of the tissues in the mid-chest) occurs; or if subcutaneous or mediastinal emphysema progresses rapidly; or if air leak or large pneumothorax is persistent despite chest tube placement. Other indications for surgery are a tear more than one third the circumference of the airway, tears with loss of tissue, and a need for positive pressure ventilation. Damaged tissue around a rupture (e.g. torn or scarred tissue) may be removed in order to obtain clean edges that can be surgically repaired. Debridement of damaged tissue can shorten the trachea by as much as 50%. Repair of extensive tears can include sewing a flap of tissue taken from the membranes surrounding the heart or lungs (the pericardium and pleura, respectively) over the sutures to protect them. When lung tissue is destroyed as a result of TBI complications, pneumonectomy or lobectomy (removal of a lung or of one lobe, respectively) may be required. Pneumonectomy is avoided whenever possible due to the high rate of death associated with the procedure. Surgery to repair a tear in the tracheobronchial tree can be successful even when it is performed months after the trauma, as can occur if the diagnosis of TBI is delayed. When airway stenosis results after delayed diagnosis, surgery is similar to that performed after early diagnosis: the stenotic section is removed and the cut airway is repaired.

Small spontaneous pneumothoraces do not always require treatment, as they are unlikely to proceed to respiratory failure or tension pneumothorax, and generally resolve spontaneously. This approach is most appropriate if the estimated size of the pneumothorax is small (defined as <50% of the volume of the hemithorax), there is no breathlessness, and there is no underlying lung disease. It may be appropriate to treat a larger PSP conservatively if the symptoms are limited. Admission to hospital is often not required, as long as clear instructions are given to return to hospital if there are worsening symptoms. Further investigations may be performed as an outpatient, at which time X-rays are repeated to confirm improvement, and advice given with regard to preventing recurrence (see below). Estimated rates of resorption are between 1.25% and 2.2% the volume of the cavity per day. This would mean that even a complete pneumothorax would spontaneously resolve over a period of about 6 weeks. There is, however, no high quality evidence comparing conservative to non conservative management.

Secondary pneumothoraces are only treated conservatively if the size is very small (1 cm or less air rim) and there are limited symptoms. Admission to the hospital is usually recommended. Oxygen given at a high flow rate may accelerate resorption as much as fourfold.

Vehicle occupants who wear seat belts have a lower incidence of TBI after a motor vehicle accident. However, if the strap is situated across the front of the neck (instead of the chest), this increases the risk of tracheal injury. Design of medical instruments can be modified to prevent iatrogenic TBI, and medical practitioners can use techniques that reduce the risk of injury with procedures such as tracheotomy.

The administration of fluid therapy in individuals with pulmonary contusion is controversial. Excessive fluid in the circulatory system (hypervolemia) can worsen hypoxia because it can cause fluid leakage from injured capillaries (pulmonary edema), which are more permeable than normal. However, low blood volume (hypovolemia) resulting from insufficient fluid has an even worse impact, potentially causing hypovolemic shock; for people who have lost large amounts of blood, fluid resuscitation is necessary. A lot of the evidence supporting the idea that fluids should be withheld from people with pulmonary contusion came from animal studies, not clinical trials with humans; human studies have had conflicting findings on whether fluid resuscitation worsens the condition. Current recommendations suggest giving enough fluid to ensure sufficient blood flow but not giving any more fluid than necessary. For people who do require large amounts of intravenous fluid, a catheter may be placed in the pulmonary artery to measure the pressure within it. Measuring pulmonary artery pressure allows the clinician to give enough fluids to prevent shock without exacerbating edema. Diuretics, drugs that increase urine output to reduce excessive fluid in the system, can be used when fluid overload does occur, as long as there is not a significant risk of shock. Furosemide, a diuretic used in the treatment of pulmonary contusion, also relaxes the smooth muscle in the veins of the lungs, thereby decreasing pulmonary venous resistance and reducing the pressure in the pulmonary capillaries.

In a large PSP (>50%), or in a PSP associated with breathlessness, some guidelines recommend that reducing the size by aspiration is equally effective as the insertion of a chest tube. This involves the administration of local anesthetic and inserting a needle connected to a three-way tap; up to 2.5 liters of air (in adults) are removed. If there has been significant reduction in the size of the pneumothorax on subsequent X-ray, the remainder of the treatment can be conservative. This approach has been shown to be effective in over 50% of cases. Compared to tube drainage, first-line aspiration in PSP reduces the number of people requiring hospital admission, without increasing the risk of complications.

Aspiration may also be considered in secondary pneumothorax of moderate size (air rim 1–2 cm) without breathlessness, with the difference that ongoing observation in hospital is required even after a successful procedure. American professional guidelines state that all large pneumothoraces – even those due to PSP – should be treated with a chest tube. Moderately sized iatrogenic traumatic pneumothoraces (due to medical procedures) may initially be treated with aspiration.

No treatment is known to speed the healing of a pulmonary contusion; the main care is supportive. Attempts are made to discover injuries accompanying the contusion, to prevent additional injury, and to provide supportive care while waiting for the contusion to heal. Monitoring, including keeping track of fluid balance, respiratory function, and oxygen saturation using pulse oximetry is also required as the patient's condition may progressively worsen. Monitoring for complications such as pneumonia and acute respiratory distress syndrome is of critical importance. Treatment aims to prevent respiratory failure and to ensure adequate blood oxygenation. Supplemental oxygen can be given and it may be warmed and humidified. When the contusion does not respond to other treatments, extracorporeal membranous oxygenation may be used, pumping blood from the body into a machine that oxygenates it and removes carbon dioxide prior to pumping it back in.

Full recovery is common with proper treatment. Pulmonary laceration usually heals quickly after a chest tube is inserted and is usually not associated with major long-term problems. Pulmonary lacerations usually heal within three to five weeks, and lacerations filled with air will commonly heal within one to three weeks but on occasion take longer. However, the injury often takes weeks or months to heal, and the lung may be scarred. Small pulmonary lacerations frequently heal by themselves if material is removed from the pleural space, but surgery may be required for larger lacerations that do not heal properly or that bleed.

A hemothorax is managed by removing the source of bleeding and by draining the blood already in the thoracic cavity. Blood in the cavity can be removed by inserting a drain (chest tube) in a procedure called a tube thoracostomy. Generally, the thoracostomy tube is placed between the ribs in the sixth or seventh intercostal space at the mid-axillary line. Usually the lung will expand and the bleeding will stop after a chest tube is inserted.

The blood in the chest can thicken as the clotting cascade is activated when the blood leaves the blood vessels and comes into contact with the pleural surface, injured lung or chest wall, or with the chest tube. As the blood thickens, it can clot in the pleural space (leading to a retained hemothorax) or within the chest tube, leading to chest tube clogging or occlusion. Chest tube clogging or occlusion can lead to worse outcomes as it prevents adequate drainage of the pleural space, contributing to the problem of retained hemothorax. In this case, patients can be hypoxic, short of breath, or in some cases, the retained hemothorax can become infected (empyema).

Retained hemothorax occurs when blood remains in the pleural space, and is a risk factor for the development of complications, including the accumulation of pus in the pleural space and fibrothorax. It is treated by inserting a second chest tube or by drainage by video-assisted thoracoscopy. Fibrolytic therapy has also been studied as a treatment.

When hemothorax is treated with a chest tube, it is important that it maintain its function so that the blood cannot clot in the chest or the tube. If clogging occurs, internal chest tube clearing can be performed using an open or closed technique. Manual manipulation, which may also be called milking, stripping, or tapping, of chest tubes is commonly performed to maintain an open tube, but no conclusive evidence has demonstrated that any of these techniques are more effective than the others, or that they improve chest tube drainage.

In some cases bleeding continues and surgery is necessary to stop the source of bleeding. For example, if the hemothorax was caused by aortic rupture in high energy trauma, surgical intervention is mandatory.

The tissues in the mediastinum will slowly resorb the air in the cavity so most pneumomediastinums are treated conservatively. Breathing high flow oxygen will increase the absorption of the air.

If the air is under pressure and compressing the heart, a needle may be inserted into the cavity, releasing the air.

Surgery may be needed to repair the hole in the trachea, esophagus or bowel.

If there is lung collapse, it is imperative the affected individual lies on the side of the collapse, although painful, this allows full inflation of the unaffected lung.

Subcutaneous emphysema is usually benign. Most of the time, SCE itself does not need treatment (though the conditions from which it results may); however, if the amount of air is large, it can interfere with breathing and be uncomfortable. It occasionally progresses to a state "Massive Subcutaneous Emphysema" which is quite uncomfortable and requires surgical drainage. When the amount of air pushed out of the airways or lung becomes massive, usually due to positive pressure ventilation, the eyelids swell so much that the patient cannot see. Also the pressure of the air may impede the blood flow to the areolae of the breast and skin of the scrotum or labia. This can lead to necrosis of the skin in these areas. The latter are urgent situations requiring rapid, adequate decompression. Severe cases can compress the trachea and do require treatment.

In severe cases of subcutaneous emphysema, catheters can be placed in the subcutaneous tissue to release the air. Small cuts, or "blow holes", may be made in the skin to release the gas. When subcutaneous emphysema occurs due to pneumothorax, a chest tube is frequently used to control the latter; this eliminates the source of the air entering the subcutaneous space. If the volume of subcutaneous air is increasing, it may be that the chest tube is not removing air rapidly enough, so it may be replaced with a larger one. Suction may also be applied to the tube to remove air faster. The progression of the condition can be monitored by marking the boundaries with a special pencil for marking on skin.

Since treatment usually involves dealing with the underlying condition, cases of spontaneous subcutaneous emphysema may require nothing more than bed rest, medication to control pain, and perhaps supplemental oxygen. Breathing oxygen may help the body to absorb the subcutaneous air more quickly.

There is no specific treatment for rib fractures, but various supportive measures can be taken. In simple rib fractures, pain can lead to reduced movement and cough suppression; this can contribute to formation of secondary chest infection. Flail chest is a potentially life-threatening injury and will often require a period of assisted ventilation. Flail chest and first rib fractures are high-energy injuries and should prompt investigation of damage to underlying viscera (e.g., lung contusion) or remotely (e.g., cervical spine injury). Spontaneous fractures in athletes generally require a cessation of the cause, e.g., time off rowing, while maintaining cardiovascular fitness.

Treatment options for internal fixation/repair of rib fractures include:

- Judet and/or sanchez plates/struts are a metal plate with strips that bend around the rib and then is further secured with sutures.

- Synthes matrixrib fixation system has two options: a precontoured metal plate that uses screws to secure the plate to the rib; and/or an intramedullary splint which is tunneled into the rib and secured with a set screw.

- Anterior locking plates are metal plates that have holes for screws throughout the plate. The plate is positioned over the rib and screwed into the bone at the desired position. The plates may be bent to match the contour of the section.

- U-plates can also be used as they clamp on to the superior aspect of the ribs using locking screws.

As with other chest injuries such as pulmonary contusion, hemothorax, and pneumothorax, pulmonary laceration can often be treated with just supplemental oxygen, ventilation, and drainage of fluids from the chest cavity. A thoracostomy tube can be used to remove blood and air from the chest cavity. About 5% of cases require surgery, called thoracotomy. Thoracotomy is especially likely to be needed if a lung fails to re-expand; if pneumothorax, bleeding, or coughing up blood persist; or in order to remove clotted blood from a hemothorax. Surgical treatment includes suturing, stapling, oversewing, and wedging out of the laceration. Occasionally, surgeons must perform a lobectomy, in which a lobe of the lung is removed, or a pneumonectomy, in which an entire lung is removed.

If left untreated, the condition can progress to a point where the blood accumulation begins to put pressure on the mediastinum and the trachea, effectively limiting the amount that the heart's ventricles are able to fill. The condition can cause the trachea to deviate, or move, toward the unaffected side.

Treatment is directed at correcting the underlying cause. Post-surgical atelectasis is treated by physiotherapy, focusing on deep breathing and encouraging coughing. An incentive spirometer is often used as part of the breathing exercises. Walking is also highly encouraged to improve lung inflation. People with chest deformities or neurologic conditions that cause shallow breathing for long periods may benefit from mechanical devices that assist their breathing. One method is continuous positive airway pressure, which delivers pressurized air or oxygen through a nose or face mask to help ensure that the alveoli do not collapse, even at the end of a breath. This is helpful, as partially inflated alveoli can be expanded more easily than collapsed alveoli. Sometimes additional respiratory support is needed with a mechanical ventilator.

The primary treatment for acute massive atelectasis is correction of the underlying cause. A blockage that cannot be removed by coughing or by suctioning the airways often can be removed by bronchoscopy. Antibiotics are given for an infection. Chronic atelectasis is often treated with antibiotics because infection is almost inevitable. In certain cases, the affected part of the lung may be surgically removed when recurring or chronic infections become disabling or bleeding is significant. If a tumor is blocking the airway, relieving the obstruction by surgery, radiation therapy, chemotherapy, or laser therapy may prevent atelectasis from progressing and recurrent obstructive pneumonia from developing.

Treatment for this condition is the same as for hemothorax and pneumothorax independently: by tube thoracostomy, the insertion of a chest drain through an incision made between the ribs, into the intercostal space. A chest tube must be inserted to drain blood and air from the pleural space so it can return to a state of negative pressure and function normally.

Commonly, surgery is needed to close off whatever injuries caused the blood and air to enter the cavity (e.g. stabbing, broken ribs).

Since the diaphragm is in constant motion with respiration, and because it is under tension, lacerations will not heal on their own. Surgery is needed to repair a torn diaphragm. Most of the time, the injury is repaired during laparotomy. Other injuries, such as hemothorax, may present a more immediate threat and may need to be treated first if they accompany diaphragmatic rupture. Video-assisted thoracoscopy may be used.

Several methods of treatment are available, mainly consisting of careful drug therapy and surgery. Glucocorticoids (such as prednisone or methylprednisolone) decrease the inflammatory response to tumor invasion and edema surrounding the tumor. Glucocorticoids are most helpful if the tumor is steroid-responsive, such as lymphomas. In addition, diuretics (such as furosemide) are used to reduce venous return to the heart which relieves the increased pressure.

In an acute setting, endovascular stenting by an interventional radiologist may provide relief of symptoms in as little as 12–24 hours with minimal risks.

Should a patient require assistance with respiration whether it be by bag/valve/mask, BiPAP, CPAP or mechanical ventilation, extreme care should be taken. Increased airway pressure will tend to further compress an already compromised SVC and reduce venous return and in turn cardiac output and cerebral and coronary blood flow. Spontaneous respiration should be allowed during endotracheal intubation until sedation allows placement of an ET tube and reduced airway pressures should be employed when possible.

Air in subcutaneous tissue does not usually pose a lethal threat; small amounts of air are reabsorbed by the body. Once the pneumothorax or pneumomediastinum that causes the subcutaneous emphysema is resolved, with or without medical intervention, the subcutaneous emphysema will usually clear. However, spontaneous subcutaneous emphysema can, in rare cases, progress to a life-threatening condition, and subcutaneous emphysema due to mechanical ventilation may induce ventilatory failure.

Individuals can benefit from a variety of physical therapy interventions. Persons with neurological/neuromuscular abnormalities may have breathing difficulties due to weak or paralyzed intercostal, abdominal and/or other muscles needed for ventilation. Some physical therapy interventions for this population include active assisted cough techniques, volume augmentation such as breath stacking, education about body position and ventilation patterns and movement strategies to facilitate breathing.

Treatment depends on the underlying cause of the pleural effusion.

Therapeutic aspiration may be sufficient; larger effusions may require insertion of an intercostal drain (either pigtail or surgical). When managing these chest tubes, it is important to make sure the chest tubes do not become occluded or clogged. A clogged chest tube in the setting of continued production of fluid will result in residual fluid left behind when the chest tube is removed. This fluid can lead to complications such as hypoxia due to lung collapse from the fluid, or fibrothorax if scarring occurs. Repeated effusions may require chemical (talc, bleomycin, tetracycline/doxycycline), or surgical pleurodesis, in which the two pleural surfaces are scarred to each other so that no fluid can accumulate between them. This is a surgical procedure that involves inserting a chest tube, then either mechanically abrading the pleura or inserting the chemicals to induce a scar. This requires the chest tube to stay in until the fluid drainage stops. This can take days to weeks and can require prolonged hospitalizations. If the chest tube becomes clogged, fluid will be left behind and the pleurodesis will fail.

Pleurodesis fails in as many as 30% of cases. An alternative is to place a PleurX Pleural Catheter or Aspira Drainage Catheter. This is a 15Fr chest tube with a one-way valve. Each day the patient or care givers connect it to a simple vacuum tube and remove from 600 to 1000 mL of fluid, and can be repeated daily. When not in use, the tube is capped. This allows patients to be outside the hospital. For patients with malignant pleural effusions, it allows them to continue chemotherapy, if indicated. Generally, the tube is in for about 30 days and then it is removed when the space undergoes a spontaneous pleurodesis.

Along with the measure above, systemic immediate release opioids are beneficial in emergently reducing the symptom of shortness of breath due to both cancer and non cancer causes; long-acting/sustained-release opioids are also used to prevent/continue treatment of dyspnea in palliative setting. Pulmonary rehabilitation may alleviate symptoms in some people, such as those with COPD, but will not cure the underlying disease. There is a lack of evidence to recommend midazolam, nebulised opioids, the use of gas mixtures, or cognitive-behavioral therapy.

No treatment is needed for correcting lung hernias. Some surgeons offer cosmetic surgery to remove the protruding mass.

Treatment of hydrothorax is difficult for several reasons. The underlying condition needs to be corrected; however, often the source of the hydrothorax is end stage liver disease and correctable only by transplant. Chest tube placement should not occur. Other measures such as a TIPS procedure are more effective as they treat the cause of the hydrothorax, but have complications such as worsened hepatic encephalopathy.