Blunt trauma of chest wall is the commonest cause of rib fracture. Patients with fracture of one or two ribs have low incidences of complications however; fractures of three or more ribs (Multiple Fractured Ribs, MFRs) have increased risk of morbidity and mortality. When multiple ribs are fractured pain relief with systemic opioids can result in over-sedation, inability for expectoration and worsening of pulmonary condition. In MFRs regional mode of analgesia is a preferred choice in the pain management. There are several regional analgesia techniques which can be used however; each technique has advantages and limitation for its usage. In current practice ultrasound guided interfacial plane blocks like serratus anterior plane block, rhomboid intercostal plane block and erector spinae plane block may provide effective pain relief without posing serious risk of procedure itself. This brief review has discussed various regional technique of pain relief in MFRs.

Blunt trauma of chest wall is the commonest cause of rib fracture [1,2]. Patients with fracture of one or two ribs have low incidences of complications [1,3] and can easily be managed with oral analgesic drugs (NSAIDs, acetaminophen) [4]. However, patient with fractures of three or more ribs (Multiple Fractured Ribs, MFRs) have increased risk of morbidity and mortality [1]. The risk of mortality is influenced by the amount of pain a patient experience. In cases of multiple rib fractures pain is usually more severe and frequently alters pulmonary mechanics. Increased pain during breathing causes shallow breath and ineffective coughing, which results in insufficient clearance of airway secretions and retention of sputum which often precipitates secondary complications [3,5,6]. Inadequate pain relief results in reduced lung compliance and ventilation-perfusion Mismatch. The combination of poor lung compliance and inadequate clearance of secretions leads to atelectasis, sepsis and pneumonia. Eventually intubation and ventilator support may be required for respiratory failure. These complications can be avoided with adequate pain relief [4,7].

Regional Techniques of Pain Relief

When multiple ribs are fractured pain relief with systemic narcotics can result in over-sedation, inability for expectoration and worsening of pulmonary condition. Therefore, when multiple ribs are fractured, regional mode of analgesia is a preferred choice in the pain management. There are several regional analgesia techniques which can be used however; each technique has advantages and limitation for its usage (Table 1). Regional techniques used to provide analgesia in multiple rib fracture are given below:

Intercostal Nerve Block (ICNB)

The intercostal nerve block is aimed at the ventral ramus of the sensory nerve that runs in the small neurovascular bundle at the inferior aspect of each rib (Figure 1). The Intercostal Nerve Block (ICNB) is an effective and simple method for pain relief however, it has many practical difficulties. First of all, many injections have to be given depending on the numbers of fracture ribs. The duration of relief is also a limitation. Studies have reported good relief up to 6-8 hrs. Only and, repeated injections become less effective [8]. Injury to the neurovascular bundle and pneumothoraces are other possible complications. Due to high absorption of local anaesthetic drugs by intercostal muscles adrenaline should be used which helps to reduce systemic absorption of local anesthetic by vasoconstriction of local vasculature. To avoid toxicity of local anaesthetic dosages also should to be kept in safe limits.

Figure 1

Intercostal Nerve Block

The landmark-based approach is performed at the posterior axillary line where the ribs can be easily palpated. This is often lateral to the division of the intercostal nerve into deep and lateral cutaneous branches and may therefore result in good anesthesia of the rib but poor anesthesia of pleura. Ultrasound guided intercostal block enables visualization of local anesthetic injection into the intercostal space, allowing the provider to adjust the needle trajectory and depth as needed to ensure adequate anesthetic spread [9]. In 1988, Vaghadia and Jenkins, et al. [10] described the use of Doppler ultrasound in three patients for Intercostal Nerve Block. The authors felt that the advantage was location of the ribs by a less painful and a more accurate method (in obese patients) than palpation. Further studies are needed to investigate the effect of intercostal nerve blockade on pain reduction and patient satisfaction and to compare intercostal nerve blockade to other analgesic strategies.

Continuous Intercostal Nerve Block

In patients with contraindications to epidural placement this technique could be a therapeutic alternative [11,12]. This technique can also be used safely in a patient who may be coagulopathic. These catheters are inserted lateral to the paraspinous muscles and tunneled perpendicular and superficial to the affected ribs in an extra thoracic location where the incidence of morbidity from a hematoma is low. In a patient taking clopidogrel as part of a regimen to treat coronary artery disease after stent placement, this technique would have allowed continuation of their antiplatelet therapy as well as alleviating the concern for neuraxial hematoma. In addition, with proper attention to issues of consent, this modality can be used in the patient who has already been intubated, where sedation and lack of patient cooperation make the risks associated with a thoracic epidural placement unacceptable.

Thoracic Para-Vertebral Block (TPB)

Injection of local anaesthetic in to thoracic paravertebral space (Figure 2) is very effective for pain relief in cases with rib fractures [13]. For multiple rib fractures, catheter technique is preferred which can provide continuous pain relief. Single injection technique requires multiple and multi-level injections which has inherent risk of complications and also inconvenient to patients. TBP has been found to be as good analgesic technique as Thoracic Epidural Analgesia [5] and is also technically less complex, with minimal hemodynamic disturbance and no concern of urinary retention or pruitis [14] One distinct advantage to PVB catheters over TEA is the ability to provide long-duration analgesia (60 hrs to 18 days) in the ambulatory setting which facilitate early ambulation and discharge from hospital [15,16]. However, there is a small risk for pneumothorax [17], vascular puncture, pleural puncture and a possibility of toxicity due to the rapid absorption of Local Anaesthetic [4]. TBP can be given by using surface landmarks, nerve stimulator guidance or Ultrasound Guidance (USG). A review suggested that USG blocks are more successful and safe then other techniques [18].

Figure 2

Thoracic Paravertebral Block

Intrapleural analgesia

For an intrapleural block, LA is deposited between the visceral and parietal layers of the pleura (Figure 3). This is usually done by inserting a catheter (A simple 18G epidural catheter can be inserted in mid axillary or posterior axillary line using Tuohy needle) and injecting local anaesthetic through that catheter either bolus or as continuous infusion. This is not a popular technique at present due to variable efficacy and side effects. Study by Bachman-Mennenga, et al. [19], and colleagues found that 70% of patients receiving the intrapleural anaesthetic needed supplemental opioids to manage pain. Other issue is the presence of a chest drain, which can cause loss of Local Anaesthetic [20]. Sometime the Local Anaesthetic can result in paralysis of the phrenic nerve and/or aggravate Bronchospasm [21]. There is also a risk for symptomatic pneumothorax [22]. If blood is present in the pleural space, the local anaesthetic will be diluted, resulting in a poor block. The rate of absorption may be rapid leading to a high plasma concentration and thus a potential risk for anaesthetic toxicity [2].

Figure 3

Intrapleural Nerve Block

Epidural Analgesia (EA)

Epidural analgesia is a gold standard for pain relief in Multiple Fractured Ribs (MFRs) [23,24]. Lumbar as well as thoracic epidural analgesia with local anesthetic or with opioids combination has been successfully used to manage pain in patients with MFRs [24]. Epidural analgesia produces superior pain relief than other technique of pain relief and also modifies the immune response in patients with chest trauma, as evidenced by a [26,27] reduction in the plasma levels of interleukin (IL)-8 [25]. Use of EA reduces the respiratory complications and length of hospital stay. However, EA is technically demanding, especially in patients distressed with pain. In patients with multiple injuries, it may cause hypotension, can result in cardiovascular collapse and cardiac arrest in the inadequately resuscitated patient. Rarely may it cause other serious complications like infection & respiratory depression. Other undesirable side effects are nausea, vomiting, urinary retention, and pruritus. Moreover, one must also consider the possibility of inadvertent dural puncture, epidural hematoma and, very rarely, spinal cord trauma after EA.

Intrathecal opioids

Intrathecal morphine via the lumbar route has been used for analgesia in MFRs [28,29]. The efficacy to control pain is variable and a study has suggested that epidural bupivacaine is superior in analgesia [29].

Epidural steroids

Rauchwerger, et al. [30] reported that pain could be controlled by injecting anaesthetics or steroids into the thoracic epidural space; it was reported to be effective for bilateral rib fractures. Injection of 80 mg depot Methylprednisolone or Triamcinolone with 0. 125 % bupivacaine (3-6 ml) in cases of multiple rib fractures can be used as a sole therapy or as an adjuvant to other analgesics.

Serratus Anterior Plane Block (SAPB), Serratus-Intercostal Plane Block (SIFB), and Pecto-Intercostal Fascial Plane Block (PIFB)

Ultrasound-guided serratus anterior Plane block has recently been described to treat patients MFRs as a regional anesthetic technique to provide analgesia (Figure 4) [31,32]. SAP block provides analgesia to a hemithorax by blocking the lateral branches of the Intercostal Nerves [33]. SAP block has also been reported to provide analgesia and to facilitate weaning from mechanical ventilation in critical care patients with MFR [35]. In this study Lopez-Matamala, et al. [34] used the similar targets (Lateral cutaneous branches) but used different nomenclature (SIFB). In this case series an additional block (PIFB) was used to block anterior cutaneous branches of Intercostal Nerves [34]. However, the benefit of giving additional interfacial block (PIFB) in management of MFRs is yet to be proved. Serratus plane block appear to be a safe, reliable means of improving pain relief following multiple rib fractures in trauma patients [35]. However, if ribs are fractured in posterior 1/3 part, the pain relief may not be adequate and may require thoracic epidural block [36].

Figure 4

Serratus Anterior Plane Block, local Anaesthetic spread below the Serratus Anterior Muscle

Parasternal Block (PSB) and Transverse Thoracic Muscle Plane Block (TTP)

Fractures of ribs in anterior part including sternal fractures are painful condition which can result in pulmonary morbidity if not treated promptly. This area is supplied with anterior cutaneous branches of intercostal nerve (Figure 1). These nerves can be blocked by injection of local anesthetic in a plane between internal intercostal muscles and transverse thoracic muscle. Ueshima and Kitamura, et al. [37] described this block first time and named TTP. They used it for surgery of breast however, similar block given for sternal fracture at parasternal area was called PSB by Thomas, et al. [38] to give this block, at the lateral border of the sternum, and internal thoracic vessels lying anterior to transverse thoracic muscle are identified. The needle is inserted in-plane to follow its tip perfectly beyond the internal intercostal muscles, anterior to the transverse thoracic muscle to block the terminal anterior branch of the intercostal nerve and spread of local anaesthetic to the perivascular sympathetic plexus. To prevent pneumothorax or pericardium puncture these blocks are reserved for experienced people.

Rhomboid Intercostal Block (RICPB)

Recently an injection of local anaesthetic below the rhomboid muscle (between rhomboid and Intercostal Muscle) was given in the area of Triangle of Auscultation (TOA) [39]. That provided the symptomatic relief in a case of fractured rib. The dermatomal coverage measured from T2-9 on the whole anterior hemithorax just medial from the midline, lateral from the axilla to T9, and on the posterior hemithorax T2-9 until immediately medial to the spinous processes. This result suggests Rhomboid Intercostal Block (RICPB) may be useful in providing analgesia for both the anterior and posterior hemithorax, but further comparisons with previously described blocks are required.

Erector Spinae Plane Block (ESPB)

The Sonoanatomy image to give ESPB is shown in (Figure 5A) and site of injection in (Figure 5B). RICPB and ESPB both work on the same target point i. e. , the dorsal and ventral ramus of thoracic spinal nerve through costotransverse for amen however; ESPB has wider coverage of dermatomes then RICPB [40,41]. These blocks provide more consistent and complete block of Intercostal nerve and their communicating branches [42] then Serratus Anterior Block [32,33]. Because the primary target in SAPB is lateral cutaneous branches [43].

Figure 5a

Sonoanatomy of Erector Spinae Plane block, LD- Latissimus Dorsi, RM- Rhomboid Major, ES- Erector Spinae, TP- Transverse Process, ICM- Intercostal Muscles

Figure 5b

Erector Spinae Plane Block, Block needle is touching the transverse process and colored arrows showing local anaesthetic spread below the erector spinae muscle

Transcutaneous Electrical Nerve Stimulation (TENS)

This method of pain relief works through release of endorphins and studies have shown effective pain relief in MFRs [44,45]. However, one study have not mentioned the extent of fractured ribs [44] and other studies have used it in uncomplicated minor rib fracture [45] it is difficult to extrapolate the utility of TENS in various degree of MFRs.

Transdermal lidocaine patches

Transdermal Lidocaine Patches [46] placed over rib fracture sites have not been shown to significantly improve pain control in patients with traumatic rib fractures.

Cervical epidural

Author has used this technique successfully to treat MFRs in two patients (Unpublished data). However, due to possibility of life-threatening complications and availability of relatively safe and effective alternatives its routine use is not suggested.

Chronic pain after MFRs

Prolonged chest wall pain is common after fractured ribs [47]. The prevalence is between 20-28 % however, no injury characteristics or therapy can predict chronic pain [48]. Various regional techniques [39,40,49,50] have shown the reduction of chronic pain incidence after chest wall surgery. However, further investigation into more effective therapies that prevent prolonged pain and disability after rib fractures is needed [48].

Early and adequate management of pain due to fractured rib is essential. Inadequate pain management may lead to significant morbidity and may risk life threatening complications. Single rib fracture pain is easy to treat however pain due to fracture of multiple ribs require more intensive approach. Regional analgesic techniques are very safe and effective technique either as a sole technique or as adjuvant. There are many techniques however, any particular method of analgesia for all patients could not be recommended. Individualized treatment technique has to be based on age, level of pain, and extent of the injury.

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