Variety of transversus thoracis muscle in relation to the internal thoracic artery: an autopsy study of 120 subjects

Optimal techniques of ultrasound-guided superficial and deep parasternal intercostal plane blocks: a cadaveric study

INTRODUCTION

The optimal techniques of a parasternal intercostal plane (PIP) block to cover the T2-T6 intercostal nerves have not been elucidated. This pilot cadaveric study aims to determine the optimal injection techniques that achieve a consistent dye spread over the second to sixth intercostal spaces after both ultrasound-guided superficial and deep PIP blocks. We also investigated the presence of the transversus thoracis muscle at the first to sixth intercostal spaces and its sonographic identification agreement, as well as the location of the internal thoracic artery in relation to the lateral border of the sternum.

METHODS

Ultrasound-guided superficial or deep PIP blocks with single, double, or triple injections were applied in 24 hemithoraces (three hemithoraces per technique). A total volume of dye for all techniques was 20 mL. On dissection, dye distribution over the first to sixth intercostal spaces, the presence of the transversus thoracis muscle at each intercostal space and the distance of the internal thoracic artery from the lateral sternal border were recorded.

RESULTS

The transversus thoracis muscles were consistently found at the second to sixth intercostal spaces, and the agreement between sonographic identification and the presence of the transversus thoracis muscles was >80% at the second to fifth intercostal spaces. The internal thoracic artery is located medial to the halfway between the sternal border and costochondral junction along the second to sixth intercostal spaces. Dye spread following the superficial PIP block was more localized than the deep PIP block. For both approaches, the more numbers of injections rendered a wider dye distribution. The numbers of stained intercostal spaces after superficial block at the second, fourth, and fifth intercostal spaces, and deep block at the third and fifth intercostal spaces were 5.3±1.2 and 5.7±0.6 levels, respectively.

CONCLUSION

Triple injections at the second, fourth, and fifth intercostal spaces for the superficial approach and double injections at the third and fifth intercostal spaces for the deep approach were optimal techniques of the PIP blocks.

Deep parasternal intercostal plane nerve block: an anatomical study

INTRODUCTION

The superficial and deep parasternal intercostal plane (DPIP) blocks are two new blocks for thoracic pain. There are limited cadaveric studies evaluating the dye spread with these blocks. In this study, we examined the dye spread of an ultrasound-guided DPIP block in a human cadaveric model.

METHODS

Five ultrasound-guided DPIP blocks were performed in four unembalmed human cadavers using an in-plane approach with a linear transducer oriented in a transverse plane adjacent to the sternum. Twenty milliliters of 0.1% methylene blue were injected between ribs 3 and 4 into the plane deep to the internal intercostal muscles and superficial to the transversus thoracis muscle layer. The chest muscles were dissected, and the extent of dye spread was documented in both cephalocaudal and mediolateral directions.

RESULTS

The transversus thoracis muscle slips were stained in all cadavers from 4 to 6 levels. Intercostal nerves were dyed in all specimens. Four levels of intercostal nerves were dyed in each specimen with variability in number of levels stained above and below the level of the injection.

CONCLUSIONS

The DPIP block spreads along the tissue plane above the transversus thoracis muscles to multiple levels to dye the intercostal nerves in this cadaver study. This block may be of clinical value for analgesia in anterior thoracic surgical procedures.

Diagnostic pitfalls in computed tomography of the chest

Anatomical variants and imaging artifacts on thoracic computed tomography (CT), when unrecognized as such, can lead to radiological misinterpretation and erroneous diagnosis. This is a concise review of 15 common CT diagnostic pitfalls due to anatomical variants and imaging artifacts which have potential to be misinterpreted as significant pathology, such as neoplasia, infection, traumatic injury, interstitial lung disease, pleural disease, or vascular lesions.

Analgesic Efficacy of an Ultrasound-Guided Transversus Thoracis Plane Block Combined with an Intermediate Cervical Plexus Block on Postoperative Pain Relief After Trans-Areolar Endoscopic Thyroidectomy: A Single Center Prospective Randomized Controlled Study

Purpose

This study aimed to investigate the analgesic effect of ultrasound-guided transversus thoracis plane block (TTPB) combined with intermediate cervical plexus block (ICPB) in the early postoperative period after trans-areolar endoscopic thyroidectomy.

Patients and Methods

A total of 62 female patients undergoing trans-areolar endoscopic thyroidectomy were randomly classified to the TTPB combined with ICPB group with ropivacaine (block group) or superficial cervical plexus block group (control group). The primary outcome measures were resting visual analogue scale (VAS) in the chest area at 6 h after surgery. The secondary outcome measures included chest resting and movement VAS score, neck resting and movement VAS score within 24 h after surgery, intraoperative remifentanil consumption, postoperative analgesia rate and analgesic requirements and patient satisfaction score for pain management at discharge.

Results

Compared with the control group, the block group at rest showed consistently lower VAS scores in the chest area at 6 and 12 h after operation; the block group at rest showed lower VAS scores in the neck at 6, 12 and 24 h after operation. Regarding movement, the VAS scores of the chest and neck area at 2, 6, 12 and 24 h after the operation were lower in the block group than in the control group. The consumption of remifentanil, rate of postoperative analgesic requirements, and consumption of postoperative rescue analgesia in the block group were lower than those in the control group. Satisfaction with pain treatment at discharge was higher in the block group than in the control group.

Conclusion

Ultrasound-guided TTPB combined with ICPB provides good analgesic effect in the early postoperative period after trans-areola endoscopic thyroidectomy.

Sensory Assessment and Block Duration of Deep Parasternal Intercostal Plane Block in Patients Undergoing Cardiac Surgery: A Prospective Observational Study

INTRODUCTION

There has been increasing interest in using deep parasternal intercostal plane (PIP) block as a supplement to multimodal analgesia regimens in cardiac surgery. The aim of this study was to observe cutaneous sensory block distribution and its duration for deep PIP blocks in patients undergoing open cardiac surgery.

METHODS

This observational, prospective clinical study consisted of 113 participants. All patients received bilateral ultrasound-guided deep PIP block with 40 ml 0.33% ropivacaine. The primary study outcome was cutaneous sensory block distribution of deep PIP blocks in patients undergoing open cardiac surgery. Secondary outcome included block duration in all participants. The area of cutaneous sensory block was tested by using a cold stimulus (ice cube) 30 min after the end of deep PIP block administration. Cutaneous sensory testing was performed once every hour after extubation until the return of normal sensation.

RESULTS

Thirty minutes after bilateral deep PIP block administration, the successful block rate of dermatomes T4 to T6 was almost 100%. However, T2 (percentage of left T2 block: 64.6%; percentage of right T2 block: 42.5%) and T3 (percentage of left T3 block: 88.5%; percentage of right T3 block: 87.6%) had a lower percentage of success. A few patients had blocked dermatomes at T1 or T7 (percentage of left T1 block: 7.08%; percentage of right T1 block: 2.65%; percentage of left T7 block: 6.19%; percentage of right T7 block: 10.6%). The mean effective duration of the deep PIP block was 17 h.

CONCLUSION

Bilateral deep PIP blocks can produce a widespread cutaneous sensory blockade with variable dermatomal distribution in the mid-sternum for a considerable effective duration.

TRIAL REGISTRATION

This study was registered in the Chinese Clinical Trial Registry (ChiCTR2100047755).

Bilateral sternalis muscle in a Sudanese cadaver

Introduction and importance

Sternalis/rectus sterni is a rare muscle found in the anterior chest wall, it occurs in 35% of humans. The early detection of its presence is critical in regular mammogram screening in order to avoid possible differential diagnostic dilemma.

Case presentation

We report here a case of the sternalis muscle observed bilaterally, it was found during routine dissection session of an elderly male cadaver in the dissection room, Faculty of Medicine, University of Khartoum.

Clinical discussion and conclusion

Sternalis muscle is a familiar entity to anatomists, but can pose a diagnostic and surgical dilemma to some clinicians. Presence of the muscle can be confusing in regular mammogram screening and CT and MRI should be utilized to clear the dilemma, and further evidence needs to be explored and studied.

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Sternalis/rectus sterni is a rare muscle found in the anterior chest wall, it occurs in 3-5% of humans.

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We report here a case of the sternalis muscle observed bilaterally, it was found during a routine dissection session of an elderly male cadaver in the dissection room, Faculty of Medicine, University of Khartoum.

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Presence of the muscle can be confusing in regular mammogram screening and CT and MRI should be utilized to clear the dilemma, and further evidence needs to be explored and studied.

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Considering its insignificant function, it could be used as a muscle flap in surgical reconstructions of the head, neck, chest wall and breast.

Comparison of Ultrasound-Guided Pectointercostal Fascial Block and Transversus Thoracic Muscle Plane Block for Acute Poststernotomy Pain Management After Cardiac Surgery: A Prospective, Randomized, Double-Blind Pilot Study

OBJECTIVE

The objective of the present study was to evaluate morphine consumption and pain scores 24 hours postoperatively to compare the effects of a bilateral pectointercostal fascial block (PIFB) with those of a transversus thoracic muscle plane block (TTMPB) on acute poststernotomy pain in cardiac surgery patients who have undergone median sternotomy.

DESIGN

Prospective, randomized, double-blinded.

SETTING

The operating room, intensive care unit, and patient ward at a university hospital.

PARTICIPANTS

Thirty-nine American Society of Anesthesiologists II-to-III patients aged 18- to-80 years, scheduled for elective cardiac surgery via median sternotomy.

INTERVENTIONS

Patients randomly were allocated to groups scheduled to receive bilateral ultrasound-guided PIFB or TTMPB.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was postoperative morphine use within the first 24 hours. Secondary outcomes were the numerical pain rating scale (NRS) scores at rest and during coughing, time of first analgesic demand from the patient-controlled analgesia (PCA) device, and rescue analgesia use. The nausea/vomiting scores, time to extubation, length of stays in intensive care and the hospital, patient satisfaction scores, and complications were also recorded. The first 24-hour morphine use did not significantly differ between the PIFB and TTMPB groups (mean ± standard deviation [95% CI], 13.89 ± 6.80 [10.83-16.95] mg/24 h and 15.08 ± 7.42 [11.83-18.33] mg/24 h, respectively, p = 0.608). No significant difference between the two groups in the NRS scores at rest and during coughing was observed; the groups had similar requirements for rescue analgesia in the first 24 hours (n [%], three [15.8] and seven [35], p = 0.273, respectively). The time from PCA to the first analgesia request was longer in the PIFB than in the TTMPB group (median [interquartile range], 660 [540-900] minutes, and 240 [161-525] minutes, respectively, p = 0.002).

CONCLUSIONS

PIFB and TTMPB showed similar effectiveness for morphine consumption within 24 hours postoperatively and in pain scores in cardiac surgery patients.

Osteopathic Palpation of the Heart

In the panorama of scientific literature, there is a paucity of literature on how to palpate the heart area in the osteopathic setting and relevant indications on which palpatory sensations the clinician should perceive during the evaluation. The article reviews the fascial anatomy of the heart area and the heart movements derived from magnetic resonance imaging (MRI) studies and describes the landmarks used by the cardiac surgeon to visualize the mediastinal area. The text sets out possible suggestions for a more adequate osteopathic palpatory evaluation and describes any tactile sensations arising from the patient's chest. To the knowledge of the authors, this is the first article that seeks to lay solid foundations for the improvement of osteopathic manual medicine in the cardiology field.

Avoiding the Internal Mammary Artery During Parasternal Blocks: Ultrasound Identification and Technique Considerations

Fascial plane chest wall blocks are an integral component to optimal multimodal postoperative analgesia in breast and cardiothoracic surgery, facilitating faster functional recovery and earlier discharge. Pectoral nerves block and serratus plane block have been used to treat postsurgical pain after breast and cardiothoracic surgeries; however, they cannot be used to anesthetize the anterior chest wall. Ultrasound parasternal block, or pectointercostal fascial block and transversus thoracis muscle plane block are two novel ultrasound-guided anesthetic and analgesic techniques that block the anterior cutaneous branches T2 to T6 intercostal nerves, providing anesthesia and analgesia to the anterior chest wall. Ultrasound parasternal block/pectointercostal fascial block and transversus thoracis muscle plane block are performed in the region of the internal mammary artery and could be considered to treat post-thoracotomy pain. This anatomic region is innervated by the anterior cutaneous branches T2-to-T6 intercostal nerves, which are obliterated during cardiac surgery artery harvesting. At the level of the fourth parasternal rib interspace, the internal mammary artery can be identified between the internal intercostal muscle and transversus thoracis muscle as a longitudinal pulsatile structure approximately 1.5 cm from the lateral border of the sternum. The transversus thoracis muscle is variable in many people and, thus, is an unreliable target and is difficult to visualize with ultrasound. Moreover, patients with a history of coronary artery bypass grafting could have tissue disruption in the transversus thoracis plane because of the internal mammary artery harvest, making transversus thoracis muscle identification more difficult. Despite ultrasound parasternal block and transversus thoracis muscle plane block having good safety profiles and reduced risk of complications, pneumothorax, local anesthetic systemic toxicity, and internal mammary artery injury or hematoma should be considered. If the block is performed before cardiac surgery, both the right and left internal mammary arteries could be damaged. The injury could render the internal mammary artery unusable for bypass grafting. If the block is performed after left internal mammary artery harvesting at the end of coronary artery bypass grafting, only the right internal mammary artery could be damaged. In patients in whom the internal mammary artery has been surgically used and the transversus thoracis muscle is difficult to visualize, ultrasound parasternal block should be considered. In patients in whom the internal mammary artery could be difficult to visualize or considering that it is in the vicinity of the transversus thoracis muscle plane block target and that the transversus thoracis muscle is difficult to visualize with ultrasound after internal mammary artery harvesting, then ultrasound parasternal block should be considered. The authors believe that ultrasound parasternal block is the safer regional technique for protecting the internal mammary artery and the pleura because it is more superficial. For this reason, ultrasound parasternal block also could be performed by inexperienced anesthesiologists. Although ultrasound parasternal block is more superficial, its superiority in terms of safety is yet to be proven. Additional studies are warranted to validate the authors' hypothesis.

Chest pain in patients with COPD: the fascia's subtle silence

COPD is a progressive condition that leads to a pathological degeneration of the respiratory system. It represents one of the most important causes of mortality and morbidity in the world, and it is characterized by the presence of many associated comorbidities. Recent studies emphasize the thoracic area as one of the areas of the body concerned by the presence of pain with percentages between 22% and 54% in patients with COPD. This article analyzes the possible causes of mediastinal pain, including those less frequently taken into consideration, which concern the role of the fascial system of the mediastinum. The latter can be a source of pain especially when a chronic pathology is altering the structure of the connective tissue. We conclude that to consider the fascia in daily clinical activity may improve the therapeutic approach toward the patient.

Sternalis muscle: an underestimated anterior chest wall anatomical variant

Over the recent years, an increased alertness for thorough knowledge of anatomical variants with clinical significance has been recorded in order to minimize the risks of surgical complications. We report a rare case of bilateral strap-like sternalis muscle of the anterior chest wall in a female cadaver. Its presence may evoke alterations in the electrocardiogram or confuse a routine mammography. The incidental finding of a sternalis muscle in mammography, CT, and MRI studies must be documented in a patient's medical records as it can be used as a pedicle flap or flap microvascular anastomosis during reconstructive surgery of the anterior chest wall, head and neck, and breast. Moreover, its presence may be misdiagnosed as a wide range of benign and malignant anterior chest wall lesions and tumors.