Ultrasound-Guided Intercostal Nerve Block

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Continuing Education Activity

The blockage of anterior branches of the intercostal nerves is a selective superficial block, with a very low incidence of complications and effective in different surgeries involving the chest wall and multiple traumas. This activity describes the intercostal nerve block and reviews the role of the interprofessional team in managing pain for patients who undergo breast and thoracic surgeries, as well as for rib fractures.


  • Describe nerve blocks considerations for patients with thoracic traumas and different breast surgeries.
  • Identify the indications for intercostal nerve block in multimodal pain management.
  • Outline the most common adverse events associated with nerve blocks.
  • Describe interprofessional team strategies for improving care coordination and communication to advance in patient's pain control and improve outcomes.


The blockage of anterior branches of the intercostal nerves is a selective superficial block, with a very low incidence of complications and effective in different surgeries involving the chest wall and for rib fractures.

Anatomy and Physiology

Thoracic spinal nerves from T1 to T11 all have anterior rami corresponding with intercostal nerves. The space located between the parietal pleura and the posterior intercostal membrane is the location where every single intercostal nerve arises from their appropriate space. In the subcostal groove of every rib, the nerve lays beneath the intercostal vessels, and they are associated with the somatic nervous system.[1] Collateral, lateral cutaneous, rami communicantes, anterior cutaneous, muscular, pleural, and peritoneal sensory are considered the diverse branches given by the intercostal nerves. 

Exclusive characteristics of the first intercostal nerve are that it is the smallest nerve of all of them, it is incorporated into the brachial plexus through a unique branch, and there is no anterior cutaneous branch. The second intercostal nerve has the sole distinctive feature that it is connected to the medial cutaneous nerve in both arms by the intercostobrachial nerve. That is responsible for the innervation of the skin surrounding the armpit, the upper medial side of the arm, and the second intercostal space as well.[2] 

Considering the pattern of innervation, the 1 to 6 intercostal nerves usually supply parietal pleura, skin, serratus posterior, levatores costarum, and intercostal muscles. The next five intercostal nerves supply innervation to several structures such as parietal peritoneum, skin, and different abdominal muscles (internal/external oblique, rectus abdominis, and transversus muscles).

 A special peculiarity that differentiates the intercostal nerves from the other spinal nerves is that they do not constitute a plexus and trace an autonomous course.


  • Postoperative pain control after lumpectomy (breast-conserving surgery), partial mastectomy or wide excision, complete mastectomy or breast reconstruction[3]
  • Multiple rib fractures[4]
  • Sternal fractures
  • Analgesia for chest wall surgery and tumors[5]
  • Analgesia for chest tubes
  • Analgesia for costochondritis
  • Analgesia in thoracic blunt trauma
  • Treat pain caused by shingles or postherpetic neuralgia
  • Pain located in the thoracic spine
  • Diagnostic nerve block for chest wall pain


There are several absolute and relative contraindications for intercostal nerve blockade.

 Absolute Contraindications

  • Patient rejection
  • Infection at the injection site
  • Patient allergic to local anesthetics
  • Unavailable sterile equipment to perform the procedure
  • High risk of local anesthetic toxicity after a second attempt or bilateral blocks
  • Lack of skills to perform the block
  • Unavailability of resuscitating kit

Relative Contraindications

  • Pediatric population
  • Demented and agitated patients
  • Unresponsive patients unable to report eventual toxicity
  • A bleeding disorder is present (hemophilia, thrombocytopenia, DIC, etc.) or patients on blood thinners like warfarin or NOAC (novel oral anticoagulants)
  • Distal extremities or organ blockade can lead to tissue ischemia
  • Previous peripheral nerve neuropathies may worsen after a nerve blockade


The following block supplies are necessary for intercostal nerve blocks:

  • US machine with a high-frequency linear transducer (8 to 13 MHz)
  • Sonographic sterile cover
  • Marking pen for marking landmarks and injection points
  • Sterile gloves with or without gown and gel
  • Clear drapes
  • Antimicrobial skin cleanser (2% chlorhexidine gluconate )
  • Peripheral nerve block 20 to 22 gauge, 4 to 5 cm, 1 and a half-inch needle
  • Local anesthetic (lidocaine 1%)
  • Needles for subcutaneous local anesthetic infiltration
  • 2x2 in. gauzes
  • 3 mL syringe / 12 mL syringe / 20 mL syringe
  • Standard American Society of Anesthesiologists (ASA) monitors applied: ECG 3 leads, HR, BP, Pulse oximetry and nasal cannula with EtCO2 detector if possible
  • Resuscitation equipment and ACLS medications (oxygen supply and masks, laryngoscopes, bag-mask, suction, defibrillator, epinephrine, phenylephrine, atropine, etc.)
  • Lipid Emulsion 20% available (intravenous lipid emulsion is an accepted treatment for severe local anesthetic systemic toxicity (LAST). Epinephrine and benzodiazepines are also helpful during this severe adverse event. We need to be careful using calcium channel blockers because they can trigger cardiac impairment and worsen the situation). 


A board-certified anesthesiologist skilled in providing competent and safe ultrasound-guided regional anesthesia should be necessary to perform this peripheral nerve block, with a registered nurse or an anesthesiology resident to assist the procedure.


The equipment necessary to perform this regional blockade in a safe and standard monitored environment usually includes labeled premedication drugs, resuscitation supplies easily identifiable, and all the equipment to perform the block readily available ideally in an induction room. It is crucial a well-trained assistant present handle medications, help with the position of the patient, and during the injection of the local anesthetics. This figure should be properly familiar with CPR and resuscitation protocols if it becomes necessary in the block area. 

Different monitors are available to decrease the risk of complications related to regional anesthesia, such as intraneural injection or needle-nerve damage. One of them may be an expendable in-line pressure-monitoring mechanism for controlling the pressure while injecting the local anesthetic in the site of the regional block, and it can be documented. Documentation of every stage of this procedure is essential in every institution performing currently regional anesthesia for ensuring an effective and safe practice.[2][6]


Intercostal nerve blocks without US guidance are performed following the next steps: 

  • The patient can be situated in the sitting, lateral, or prone position prior to performing the block. The sitting one should lean to some degree forward with a pillow between their arms to retract the scapulae, and some support is needed.
  • After cleaning the skin with an antiseptic solution, it is important to identify the block sites (like the inferior borders of the targeted ribs) at around 6 to 8 cm from the midline, and they should be marked over the skin.
  • Infiltration of the needle sites with the preferred local anesthetic.
  • Introduction of the needle in the sagittal plane and advance it approaching the inferior edge of the correspondent rib ending in the subcostal groove.
  • A little dose of local anesthetic should be injected to desensitize the periosteum.
  • The needle is advanced at this point forward only 2 to 3 mm, and the clinician should feel a “pop” of the fascia close to the internal intercostal muscle, with or without the existence of paresthesia. What is anesthetized is usually helpful to ensure the correct position of the needle.
  • The injection of 3 ml to 5 ml of local anesthetic is recommended, making sure their aspiration for blood is negative.
  • The clinician should repeat the previous steps as needed to achieve the desired level of anesthesia.[5] 


  • Place the high-frequency linear transducer in a transverse orientation in order to identify the external, internal, and innermost intercostal muscle layers between ribs (image 1).
  • Power Doppler or B-mode is normally used to localize the blood vessels, keeping in mind that caudal to the arteries lie the intercostal nerve.
  • After localizing the angle of the rib with a long-axis view, the clinician now should insert the needle in-plane aimed centrally and administer the local anesthetic 2 cm medial to that situation under the costal groove, always controlling needle tip as it is advanced. The local anesthetic should be deposited between the innermost intercostal muscle and internal intercostal muscle layers (image 1).
  • It is crucial to aspirate for blood to ensure the needle is not intravascular.
  • An indentation in the pleura is often shown in the sonogram after the intercostal block is performed.
  • A single injection can spread centrally the drug of choice to anesthetize different intercostal spaces.
  • Multiple levels should be often required to provide a better quality of analgesia.
  • Detailed calculation of the doses of local anesthetic is necessary because the peak plasma levels after this block are pretty high and occur quickly.[2][6]


It is considered that a dose of the local anesthetic agent of 0.1 to 0.15 ml/kg per intercostal space (maximum dose 2 to 3 ml per space) can be administered after making sure that the tip of the needle is in the proper tissue plane. Common medications used for this blockade are ropivacaine 0.2%, levobupivacaine 0.25%, or bupivacaine 0.25%.[7][8][9]

The fairly new liposomal bupivacaine is a safe option for the management of severe pain in patients undergoing a thoracotomy or mastectomy as well.[10][11][12]


  • Arterial puncture (anterior thoracic artery injury) and hemothorax
  • Local anesthetics systemic toxicity (LAST)
  • Local infection
  • Pain during procedure
  • Pneumothorax
  • Nerve damage
  • Pleural injury
  • Fail technique
  • Catheter malposition or dislodgement
  • Muscle laceration[13]

Clinical Significance

This single specific block commonly provides around 8 to 12 hours of analgesia with fewer complications compared with other different blocks or epidural injections, and even a shorter learning curve. Besides that, it is demonstrated up to 72 hours of pain relief when liposomal bupivacaine suspension is administered intraoperatively as part of this intercostal block.[10] With the consideration of not to exceed the maximum dose of 266 mg and combined with multimodal analgesia, it would require fewer doses of opioids given to the patient.[14]

Enhancing Healthcare Team Outcomes

Clinicians performing intercostal nerve block need to be well trained in recognizing the thoracic anatomy using the ultrasound and be familiar with anatomic variations as well. Besides that, to provide a safe technique, all the necessary equipment should be readily available, and good communication with the assistant during the procedure is crucial. Complications like hemopneumothorax, intravascular damage, or severe toxicity anesthetics-related should be minimized, and early recognition and urgent management by the providers of the regional block is mandatory. Multiple randomized trials found that a well organized interprofessional team of health workers from different specialties decreases the risk of severe adverse events while performing successful regional anesthesia. [Level 1]

(Click Image to Enlarge)
Ultrasound image showing intercostal nerve block landmark
Ultrasound image showing intercostal nerve block landmark
Contributed by Rosa Lopez, MD
Article Details

Article Author

Rosa Lopez-Rincon

Article Editor:

Vikas Kumar


7/31/2021 3:57:54 PM



Bijkerk E,Cornelissen AJM,Sommer M,Van Der Hulst RRWJ,Lataster A,Tuinder SMH, Intercostal nerve block of the anterior cutaneous branches and the sensibility of the female breast. Clinical anatomy (New York, N.Y.). 2019 Dec 14;     [PubMed PMID: 31837172]


Zinboonyahgoon N,Luksanapruksa P,Piyaselakul S,Pangthipampai P,Lohasammakul S,Luansritisakul C,Mali-Ong S,Sateantantikul N,Chueaboonchai T,Vlassakov K, The ultrasound-guided proximal intercostal block: anatomical study and clinical correlation to analgesia for breast surgery. BMC anesthesiology. 2019 Jun 5;     [PubMed PMID: 31164083]


Karmakar MK,Ho AM, Acute pain management of patients with multiple fractured ribs. The Journal of trauma. 2003 Mar;     [PubMed PMID: 12634549]


Truitt MS,Murry J,Amos J,Lorenzo M,Mangram A,Dunn E,Moore EE, Continuous intercostal nerve blockade for rib fractures: ready for primetime? The Journal of trauma. 2011 Dec;     [PubMed PMID: 22182865]


Taylor R,Massey S,Stuart-Smith K, Postoperative analgesia in video-assisted thoracoscopy: the role of intercostal blockade. Journal of cardiothoracic and vascular anesthesia. 2004 Jun;     [PubMed PMID: 15232812]


Chen N,Qiao Q,Chen R,Xu Q,Zhang Y,Tian Y, The effect of ultrasound-guided intercostal nerve block, single-injection erector spinae plane block and multiple-injection paravertebral block on postoperative analgesia in thoracoscopic surgery: A randomized, double-blinded, clinical trial. Journal of clinical anesthesia. 2020 Feb;     [PubMed PMID: 31330457]


Lynch N,Salottolo K,Foster K,Orlando A,Koola C,Portillo V,Tanner A 2nd,Mains CW,Bar-Or D, Comparative effectiveness analysis of two regional analgesia techniques for the pain management of isolated multiple rib fractures. Journal of pain research. 2019;     [PubMed PMID: 31213882]


Zhang P,Liu S,Zhu J,Rao Z,Liu C, Dexamethasone and dexmedetomidine as adjuvants to local anesthetic mixture in intercostal nerve block for thoracoscopic pneumonectomy: a prospective randomized study. Regional anesthesia and pain medicine. 2019 Aug 8;     [PubMed PMID: 31399540]


Wang Y,Cheng J,Yang L,Wang J,Liu H,Lv Z, Ropivacaine for Intercostal Nerve Block Improves Early Postoperative Cognitive Dysfunction in Patients Following Thoracotomy for Esophageal Cancer. Medical science monitor : international medical journal of experimental and clinical research. 2019 Jan 16;     [PubMed PMID: 30647402]


Khalil KG,Boutrous ML,Irani AD,Miller CC 3rd,Pawelek TR,Estrera AL,Safi HJ, Operative Intercostal Nerve Blocks With Long-Acting Bupivacaine Liposome for Pain Control After Thoracotomy. The Annals of thoracic surgery. 2015 Dec;     [PubMed PMID: 26507422]


Wu C,Ma W,Cen Q,Cai Q,Wang J,Cao Y, A comparison of the incidence of supraventricular arrhythmias between thoracic paravertebral and intercostal nerve blocks in patients undergoing thoracoscopic surgery: A randomised trial. European journal of anaesthesiology. 2018 Oct;     [PubMed PMID: 29847363]


Dominguez DA,Ely S,Bach C,Lee T,Velotta JB, Impact of intercostal nerve blocks using liposomal versus standard bupivacaine on length of stay in minimally invasive thoracic surgery patients. Journal of thoracic disease. 2018 Dec;     [PubMed PMID: 30746233]


Ueda K,Hayashi M,Murakami J,Tanaka T,Utada K,Hamano K, Intercostal block vs. epidural analgesia in thoracoscopic lung cancer surgery: a randomized trial. General thoracic and cardiovascular surgery. 2019 Aug 31;     [PubMed PMID: 31473913]


Mogahed MM,Elkahwagy MS, Paravertebral Block Versus Intercostal Nerve Block in Non-Intubated Uniportal Video-Assisted Thoracoscopic Surgery: A Randomised Controlled Trial. Heart, lung     [PubMed PMID: 31147190]