Flail chest is a critical medical condition where three or more consecutive ribs are fractured in two or more locations, causing a chest wall segment to move abnormally during breathing. This condition may cause significant pain, difficulty breathing, low oxygen levels in the blood, and unstable blood pressure. Problems with ventilation, lung bruising, collapsed lung tissue, lung infection, or heart injury typically cause these symptoms. Elderly patients and individuals with multiple trauma or underlying comorbidities have significantly elevated morbidity and mortality rates to flail chest. The management strategy for flail chest has transitioned from conservative treatment, which includes analgesia and mechanical ventilation (MV), to surgical fixation of rib fractures using plates or wires. This summary reviews three recent peer-reviewed articles on flail chest, addressing questions about the disease state.
Suggested Modalities Based on Patient’s Clinical Status
The articles recommend various management strategies for flail chest depending on the patient’s clinical condition, including non-operative treatment, which includes pain management, oxygen therapy, physical therapy, and mechanical ventilation (MV) in severe cases; surgical fixation of the rib fractures, which can reduce pain, improve lung function, shorten MV duration, and lower complication rates; and extracorporeal membrane oxygenation (ECMO), which can provide respiratory and circulatory support. Perera and King (2022) state that non-operative treatment is the norm for most flail chest patients. However, it has been linked to mortality, longer MV, ICU stays, pneumonia, and other complications. According to Marasco et al. (2022), surgically fixing rib fractures can enhance pulmonary mechanics, lower the need for analgesics, restore stability to the chest wall, and lessen the need for MV and tracheostomy. ECMO is described by Wijffels et al. (2018) as a salvage therapy for flail chest patients with refractory hypoxemia or hypercapnia caused by ARDS. Still, they warn that it is a complex and expensive intervention that requires careful patient selection and specialist hospitals.
Comparison of Different MV Settings and Advantages for the Assigned Disease State
Patients with flail chest who suffer respiratory failure or ARDS frequently need MV. In patients with low lung compliance brought on by ARDS or pulmonary edema, VCV may result in high peak airway pressures and barotrauma, according to Perera and King (2022). PCV can reduce peak airway pressures and improve gas distribution, but in patients with high lung compliance due to chest wall instability or pulmonary contusion, it may result in hypoventilation and hypercapnia. Additionally, they advise using PSV to lessen breathing effort and aid in weaning off of MV but caution that in patients with solid respiratory drive brought on by pain, anxiety, or hypoxia, it may result in hyperventilation and respiratory alkalosis. Wijffels et al. (2018) concur that PCV and PSV may be helpful for patients with flail chest, but they stress that the best MV settings should be tailored to the patient’s condition, reaction, and tolerance.
Impact of the Disease State on O2 Requirements and Proven Remedies
Several factors, including paradoxical chest wall movement, which decreases lung volumes and causes ventilation-perfusion mismatch, atelectasis, which is the collapse of alveoli as a result of reduced lung expansion and increased secretions, pulmonary contusion, which is the bruising of the lung tissue as a result of blunt trauma and causes inflammation, edema, and hemorrhage, and ARDS, a severe form of lung injury, can impair gas exchange and increase O2 requirements. The articles discuss some proven treatments or interventions that can increase O2 delivery and decrease O2 demand in flail chest patients, including adequate pain control, which can lessen sympathetic stimulation and improve chest wall movement, coughing, and secretion clearance; oxygen therapy, which can correct hypoxemia and prevent tissue hypoxia by increasing the fraction of inspired oxygen (FiO2); positive end-expiratory pressure (PEEP), which can prevent alveolar hypoxia; and supplemental oxygen therapy, which can improve tissue According to Marasco et al. (2022), multimodal analgesia with regional approaches (such as epidural or paravertebral blocks) can offer more significant pain relief and respiratory results compared to systemic opioids. They also stress that pain control is the cornerstone of flail chest therapy. Depending on the patient’s oxygenation status and tolerance, oxygen therapy can be administered using various tools (such as a nasal cannula or mask) or techniques (such as high-flow nasal oxygen or non-invasive ventilation). To combat the effects of atelectasis and pulmonary edema on gas exchange, they also advise using PEEP by MV or non-invasive ventilation. According to Wijffels et al. (2018), individuals with flail chest who have ARDS can lower their risk of ventilator-induced lung injury and mortality by adhering to the ARDSNet protocol or other equivalent protocols. However, they caution that executing in patients with an unstable chest wall or multiple injuries may be challenging. They also indicate that prone positioning can be considered a rescue therapy for flail chest patients with persistent hypoxemia brought on by ARDS.
Changes in Acid-Base Balance with Improvement or Deterioration
A flail chest can cause alterations in the patient’s acid-base balance, resulting in respiratory acidosis, pulmonary alkalosis, metabolic acidosis, or metabolic alkalosis. Perera and King (2022) state respiratory acidosis can develop in flail chest patients with insufficient ventilation or oxygenation. It can worsen with comorbidities like sepsis, pneumonia, or acute renal injury. They propose that respiratory acidosis can be improved by pain management, oxygen therapy, mechanical ventilation (MV), or rib fracture fixation. According to Wijffels et al. (2018), respiratory alkalosis can be brought on by excessive ventilation or oxygenation and can worsen with hypovolemia, hypotension, or shock. Respiratory alkalosis can be improved with adequate fluid resuscitation, sedation, or MV settings. Marasco et al. (2022) report metabolic acidosis, which can worsen with multiple organ dysfunction syndrome, septic shock, or acute kidney injury. Metabolic acidosis can be improved with adequate oxygen delivery, fluid resuscitation, renal replacement treatment, or particular antidotes. Perera and King (2022) discuss metabolic alkalosis as a result of increased acid loss or decreased acid generation, which can worsen with hypokalemia, hypochloremia, hypovolemia, or aldosteronism. Metabolic alkalosis can be improved by replacing lost fluid and electrolytes, adding more acid, or using particular antagonists.
Hemodynamic Considerations for Underlying Disease States and Assessment of Improvement or Deterioration
Patients who have flail chests face hemodynamic difficulties for a variety of reasons. Marasco et al. (2022) emphasize that surgically fixing rib fractures can improve hemodynamics by restoring intrathoracic pressure, but chest wall instability decreases venous return and cardiac output. According to Perera and King (2022), pulmonary vasoconstriction and hypertension are stimulated by hypoxia and hypercapnia, but treatments like oxygen therapy, PEEP, NO, PGI2, sildenafil, or ECMO can reduce them. According to Wijffels et al. (2018), ARDS and pulmonary edema increase pulmonary vascular resistance, although interventions including ECMO, fluid restriction, diuretics, and lung protective ventilation can lessen lung damage. Additionally, fluid resuscitation, vasopressors, inotropes, or antibiotics can raise blood pressure and reduce systemic vascular resistance in sepsis and shock, respectively (Perera and King, 2022). To help flail chest patients feel better, these interventions focus on hemodynamic characteristics such as preload, afterload, contractility, heart rate, and pulmonary hypertension.
Pharmacological Considerations for Treating the Disease
Regional analgesia approaches offer superior pain relief and respiratory results compared to systemic opioids. Analgesics are essential for controlling the flail chest. Anti-inflammatory medications, such as corticosteroids, help lessen pulmonary edema and inflammation in ARDS patients with flail chest, although caution is advised due to possible side effects (Perera and King, 2022; Marasco et al., 2022; Wijffels et al., 2018). Patients with flail chests are advised to take antibiotics to prevent or treat pneumonia or sepsis, but the results of culture and sensitivity tests should determine the usage of antibiotics. In patients with fluid overload who have flail chest, diuretics help reduce pulmonary edema, but they need to be carefully monitored. Norepinephrine and dobutamine are vasopressors and inotropes that can increase blood pressure and enhance tissue perfusion in certain circumstances. However, their administration should be approached with caution. Anticoagulants are utilized to treat or prevent deep vein thrombosis or pulmonary embolism, considering associated bleeding risks (Perera and King, 2022; Marasco et al., 2022; Wijffels et al., 2018). Finally, naloxone, an antidote for opioids, should be administered with strict supervision to reverse their detrimental effects in patients with flail chest.
Weaning Protocol or Guideline for Ventilator Liberation in the Disease State
A key objective in treating patients with flail chests is weaning them off mechanical ventilation. The weaning procedure should be customized to each patient’s unique demands and responses because there is no consensus on this population’s optimum weaning protocol or guideline (Wijffels et al., 2018). Using gradual and progressive techniques like PSV, SIMV, or SBT, as well as monitoring various parameters like respiratory rate, tidal volume, minute ventilation, RSBI, MIP, oxygen saturation, arterial blood gas analysis, and subjective symptoms are some general principles for weaning that need to be followed (Perera & King, 2022; Wijffels et al., 2018). According to Perera and King (2022; Wijffels et al., 2018), weaning failure can be brought on by conditions such as unstable chest walls, pain, infections, fluid overload, cardiac malfunction, or psychological stress. Operative fixation of flail chest segments, which may increase chest wall stability, lessen pain, and improve pulmonary mechanics, are some interventions that make weaning easier. Non-operative measures like analgesia, physiotherapy, bronchodilators, and nutritional support may also help improve lung function and lessen complications (Marasco et al., 2022; Wijffels et al., 2018). To find the best weaning plan for patients with flail chest, more study is required because the data for the efficacy of these therapies is limited and contradictory (Marasco et al., 2022; Wijffels et al., 2018).
Marasco, S., Jacqueline Nguyen Khuong, Fitzgerald, M., Summerhayes, R., Mir Wais Sekandarzad, Varley, V., Campbell, R. J., & Bailey, M. (2022). Flail chest injury—changing management and outcomes. 49(2), 1047–1055. https://doi.org/10.1007/s00068-022-02152-1
Perera, T. B., & King, K. C. (2022, July 19). Flail Chest. Nih.gov; StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK534090/
Wijffels, M. M. E., Hagenaars, T., Latifi, D., Van Lieshout, E. M. M., & Verhofstad, M. H. J. (2018). Early results after operatively versus non-operatively treated flail chest: a retrospective study focusing on outcome and complications. European Journal of Trauma and Emergency Surgery, 46(3), 539–547. https://doi.org/10.1007/s00068-018-0961-4