A simple solution for surgical field improvement during electrocautery, implantation and expansion for breast reconstruction.

Abstract

We present a simple solution to the specific problem of intraoperative pectoral major muscle spasm during electrocautery and manipulation through a novel ultrasound guided injection called the INTRAPEC technique. Our case study illustrates an simple, cost effective, non-parenteral method to improve the surgical field during pectoral major isolation and subsequent implant placement. This technique may have added benefits such as a significant reduction in surgical complexity causing trauma and bleeding, and post operative pain reduction.

Key words: INTRAPEC, ultrasound, spasm reduction during electrocautery

Introduction

Regional anesthetic techniques for plastic surgery present a particular set of challenges for the anesthesia provider. Two recognized issues are the complex, wide and sometimes not well described pain generators from extensive areas involved with plastics procedures, and the risk of LAST (local anesthetic systemic toxicity). The latter is arguably due to additional doses of local anesthetics administered by our surgical colleagues in the form of Tumescent fluid. For the past several years the PECs 1 and 2 blocks have gained popularity as an effective, opioid sparing, multi modal, and pain reducing technique for analgesia for breast and anterior trunk surgical pain. The techniques continue to gain momentum for their ease of placement and safety, compared to prior techniques such as the thoracic epidural and paravertebral blocks. In theory, the PEC 1 technique, involving ultrasound guided placement of local anesthetic between the pectoralis major and minor, should denervate the muscle group reducing spasm and irritation caused by surgical manipulation and subsequent placement of expanders or implants. Additionally, during pocket creation, these muscle planes are violated, and may cause the complete release of the carefully placed local anesthetic, dramatically altering its expected duration of action. 

Like all other nerve block techniques, the PECs 1 block does not cause intramuscular flaccidity during electrical dissection (electrocautery). This spasm of the muscle has been a source of contention between our surgical colleagues and anesthesia since surgery with muscle relaxants began. The spasm and muscle contraction of the pectoralis major during the dissections and space creation for implantation, remains problematic, despite denervation occurring at the myo-neural junction through the PECs 1 technique.

We theorize that an ultrasound guided injection of the pectoralis major muscle, done well ahead of the surgical dissection and space creation, might improve pectoralis muscle rigidity and spasm and potentially added trauma and bleeding during surgical techniques involving implantation. This may improve surgical field conditions during this phase of surgery, and potentially reduce, pain, spasm and any need for intravenous muscle relaxants. We also theorize that this technique may improve post operative pain outcomes as a direct result of reduced muscle confrontation leading to trauma and spasm that occur during surgery. 

Background 

Intramuscular injections for the relief of pain and spasm is not a new concept. Pain providers employ a range of such techniques for a variety of ailments. Some such examples are intramuscular injections for the relief of piraformis syndrome, IT band release, and various posterior trunk musculature injections for trigger point treatment. These injections share commonalities that are all relieved by the injection of local anesthetic into them. Additionally they all involve elements of pain and spasm reduction, the need for analgesic medicines. It’s also possible that the evolution of chronic pain following breast reconstruction may originate from spasm and irritation of the pectoral compartment containing the medial and lateral pectoral nerves by the implant itself.  Surgical denervation of neuroma secondary to this pain syndrome is a common element for certain breast reconstruction procedures, sacrificing sensation in most cases and function in others. In many cases, this intramuscular injection can release spasm and pain for these conditions. We suggest that infiltration of the pectoralis major muscle (INTRAPEC), can reduce the spasm of the pectoral major muscle during electrocautery and potentially into the recovery phase.

Review of literature

A pubmed search for “pectoral muscle injection” was performed yielding several relevant articles. Many of the articles suggested using the PECs blocks for acute and chronic pain treatment following breast surgery. Interestingly, several articles reported post operative treatment of existing pectoralis major muscle spasms with intramuscular injections of Botox-A. However, we did not locate any articles directly using a pre-operative ultrasound guided intramuscular injection for the purpose of spasm reduction during surgery or to reduce post operative pain. 

In 2011 O’Donnell and colleagues successfully treated a patient with persistent post breast surgery pectoral muscle spasms with in intramuscular injection (1). This is one example of employment of Botox-A treatment for pectoral muscle conditions relating to surgery suggesting proof of concept for an intramuscular injection. Govshievich and colleagues reported a case presentation involving, again, a post operative pectoral muscular pain following breast surgery. This involved using the novel PECs 1 block as a diagnostic measure to more accurately identify the pain generator for this persistent pain. The PECs 1 block was done using ultrasound with symptom relief (2). Shin and colleagues described combination intramuscular injections of the subscapularis and pectoralis major muscles for the relief of post mastectomy shoulder pain. They found that post mastectomy patient benefitted from this combination technique.  Their technique does describe an intramuscular injection performed under ultrasound. However, again, it targeted post operative treatment options for these persistent symptomatic patients. No mention of preoperative placement is fund (3). In 2014, Leiman and colleagues reported an early use of Exparel (liposomal bupivacaine) in an ultrasound guided PECs 1 block for management of post operative pain following breast surgery (4). This technique involves placement of local in the fascial plane between the pectoralis major and minor targeting the medial and lateral pectoral nerves. However, it should be noted that, at the time of this writing, Exparel is not currently cleared for “nerve blocks” although there have been several articles that have successfully and safely employed its use for that specific purpose. Finally, Fallico and team reported the use of an injection of the pectoral muscle, using Botox-A, for relief of pectoral muscle spasms in 2011. Although the team report favorable results of the intervention, the pectoral muscle was used as a flap for head and neck surgery surgery, and is not exactly in league with this topic. But mention of the technique is warranted to support proof of concept (5). 

Patient presentation

Our candidate was a 20 year old female, ASA category 1 patient void of any co-morbidities or prescribed home medications. She denied any prior surgical exposure, specifically breast procedures. She denied any allergies, illicit drug or alcohol use, and was void of any physical or mental disabilities. The only discomfort she stated prior to the procedure was menstrual pain. She presented to the office based surgery suite with desire for bilateral breast augmentation. She was informed of the anesthesia plan involving general anesthesia with laryngeal mask airway, in combination of PECS 1, PECs 2 and additional technique we termed INTRAPEC injection. She demonstrated understanding of the risks and benefits and agreed to proceed. 

Technique 

The patient self positioned herself on the operating room table. The institutional time out was performed, and monitors and oxygen were applied. The patient’s baseline vitals were taken, and general anesthesia with placement of LMA easily performed. The skin was prepped with sterile chlorhexidine, and sterile single use gel applied to the suspected areas of interest. A probe cover (SaferSonic, Highland Park, IL) was applied and ultrasound image optimized. The ultrasound guided INTRAPEC technique was accomplished with the use of a high frequency linear transducer (Terason L15 paired with a Terason 3300 ultrasound system, Burlington, MA). The probe was positioned transverse over the anterior chest below the clavicle, beginning at the origin of the pectoral major medially, similar to that described by Blanco for the PECs 1 technique. The inferior and posterior border was identified sonographically and were specifically targeted. This pectoral major muscle was located under a layer of breast tissue. An 80 mm, 22G echogenic needle (Pajunk, Germany) was introduced from medial to lateral following placement not the PECs 1 block. The goal of the injection was to concentrate local anesthetic to the aponeurosis of this anterior and inferior border of the pectoral major muscle. Doppler mode was engaged to assist in the location of vasculature in the region of interest. Following aspiration and complete expulsion of all air from the needle, connective tubing and syringe, high concentration of a mixture of lidocaine 2% and ropivacaine 0.5% was infiltrated. Total volume of 15 ml per muscle was placed. The injection was safely performed in a medial to lateral fashion, promoting safety by directing the needle away from the deeper thoracic structures.

See included figures for actual patient ultrasound imaging of INTRAPEC procedure

The image below (figure 1) shows the right sided INTRAPEC technique. The needle is correctly placed into the anterior/inferior border of the pectoral major muscle. The injectate can be seen early in the deposition phase. 

Figure 1

Results 

We report two aspects of this technique, the results from the surgeons experience during electrocautery and implantation, and the patients experience of pain following surgery. The surgeon stated that the creation of surgical pocket was considerably easier, and was accomplished without unpredictable muscle contraction during periods of electrocautery or manipulation via lighted retractor. Additionally the surgeon stated that the surgical field was more easily maintained free of muscle spasm and bleeding. This seemed to promote ease of implant placement. The surgeon reported favorable results and was agreeable to reproducing the technique on future cases. The patient reported only ‘pressure” from the surgical procedure, however, complained of intense menstrual pain. She also stated that she had more pressure like discomfort to the right breast than the left. It was clear that the incisional and surgical region was not causing the patient discomfort. However she was given 1 PO oxycodone, per surgical post operative regimen, to ease her abdominal discomfort prior to her ride home. Post operative day one, she needed no pain medication, and had only “occasional discomfort”.

Discussion 

We made observations during the placement of the INTRAPEC injection. Firstly, the infiltration can be easily accomplished immediately following the PECs 1 block, as the needle is nearly in the correct position at that time. This suggests ease of placement and a small learning curve for those already employing the PECs 1 block. During the surgical procedure, specifically during the dissection and pocket creation of the pectoral major muscle, extremely little muscle contraction was seen during electrocautery. When asked how the pocket creation was compared to similar patients with similar presentations, the surgeon stated “it was like the muscle was completely paralyzed”. This notion alone, that the problem of muscle spasm during electrocautery could be significantly improved with the simple addition of local anesthetic represents a bold step forward for both anesthesia providers and surgeons. This opens the door to more ultrasound guided regional injections for a variety of purposes, potentially making optimal surgical fields less reliant on IV muscle relaxants.  

We recognize some limitations and drawbacks from the addition of the ultrasound guided INTRAPEC injection technique. The first element is the careful observation of the total dose of local anesthetic and potential of LAST (local anesthetic systemic toxicity). This element should be carefully considered as it’s unique to this patient population and plastic surgery regarding the addition of Tumescent fluid. Addition of tumescent fluid commonly incorporates larger volumes of local anesthetics as a part of their surgical regimen. As the INTRAPEC technique might be likely be added to existing techniques such as the PECs 1 and 2 blocks, or other truncal techniques, this total dose should be carefully considered. Muscle relaxation facilitated by local anesthetics is likely associated with high concentration of locals, so the careful consideration of total dose is advised.

The potential for disastrous needle misadventure should also be mentioned. In novice hands, this technique may pose significant complications to the patient in the form of structure violation. this can lead to conditions such as cardiac tamponade, pneumothorax, or large vessel puncture such as the subclavian artery or vein. However, a more likely scenario might be puncture of a smaller vessel known to be in this region such as the thoraco-acromian artery. This artery is reliably found on ultrasound between the pectoralis major and minor during the PEC 1 block. 

It is possible for the surgeon to simply inject the inferior anterior border during dissection or under direct visualization following exposure. However, the delayed onset of this injections effect to reduce spasm and reactivity to electrocautery, makes early infiltration (such as preoperative or following induction) sensible. It’s likely that by the time the patient is ready for surgical dissection, the effects of the INTRAPEC technique will have peaked. In addition, the safety of ultrasound guidance for vessel identification and needle guidance accuracy will be lost with a direct vision technique.

A postoperative injection employing the same technique could be suggested as well. However, preoperative placement without an implant yields natural muscular architecture, making the sonographic landscape easier to navigate. The incidental placement or trapping of air in anywhere in the surgical field, would have deleterious effects in ultrasound imaging acquisition. Lastly, a fresh implant and carefully closed plastic surgery incision should be cautiously negotiated with further blocks. Accidental opening of these incisions for the plastics patient can lead to further closure revision, undesirable scar formation, infection, implant violation or other avoidable complications. This should likely be avoided if possible by simply placing the INTRAPEC injection prior to incision and plane rearrangement.

Conclusions

Ultrasound guided INTRAPEC injection appears to enhance surgical field compliance during breast implantation for reconstruction and augmentation. The technique suggests that by injecting the muscle itself, at the anterior/inferior border near the aponeurosis, assists in less spasm, incidental trauma and bleeding, and reduced muscle confrontation to the surgeon.  The placement of the injection is relatively simple and straightforward and can easily be accomplished in conjunction with a PECs 1 block. The technique is further made safer by the addition of ultrasound guidance. This seems evident by not only improved accuracy from an in-plane needle guidance, but avoidance of significant structures, arguably only centimeters away from the target zone. Further safety is offered during the placement by the advantage of color Doppler viewing to assist in identification of vasculature in the infiltration zone. We look forward to and recognize the need for more formalized studies that investigate this simple technique of surgical field improvement and potential pain reduction for surgical patients undoing breast expansion or augmentation. Lastly, by it’s very nature of being both a novel technique and a single case study, we recognize that while successfully demonstrating proof of concept, it is in it’s infancy, and clearly more studies are required to validate it’s use.

Sources

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    Pectoral muscle spasms after mastectomy successfully treated with botulinum toxin injections.
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  5. Treatment of pectoralis major flap myospasms with botulinum toxin type A in head and neck reconstruction
    Email the author Luca A. Dessy, Nefer Fallico, Antonio Rampazzo, Bahar Bassiri, Marco Mazzocchi, Nicolò Scuderi, Hung-Chi Chen
    Published Online: November 10, 2011