Discussion:
The deletion of the 4q chromosome is a rare deletion syndrome with only around 200 cases reported in the literature.2 Based on the genetic analysis completed by Xu et al., the congenital heart defects associated with this syndrome have been localized to the 4q32.2-q34.3 region.2 Our patient demonstrated deletions of the terminal end of this region (q34.1 - q35.2), which may have precipitated their PFO and PDA. The heart defects were visualized via echocardiogram on Day Two of life were evaluated and thought to likely close spontaneously without intervention. Upon preoperative physical exam by the anesthesia team, the patient’s cardiovascular exam was grossly normal. However, close monitoring of their cardiovascular status was implemented due to their history of 4QDS. The patient’s status was well-maintained throughout the procedure.
Our patient also presented with dysmorphic features associated with 4QDS such as flattening of the midface and nasal root, upturned nostrils, a high-arched palate, triangular mouth and posteriorly rotated, low-set ears - all features that could be concerning for intubation. Despite these dysmorphic features, the patient’s ASA score was deemed a II and without concern for a difficult airway, which would suggest the patient was a good candidate for minimal, moderate or deep sedation4. However, considering the patient’s anomalies, there was a concern for the airway requiring a smaller than expected ETT, especially since prior reports of 4QDS have demonstrated such.4,5
Per the 2022 American Society of Anesthesiologists (ASA), pediatric patients perceived as difficult or potentially difficult can be managed using an airway management algorithm with an emphasis on team-based care.6 This care includes the use of video laryngoscopy to maximize visualization of a patient’s airway and minimize airway intubation attempts. As such, video laryngoscopy via C-MAC® was chosen for intubation with success in one attempt. Dearlove and Sharples present a case report that highlighted a 4QDS patient whose laryngoscopic imaging demonstrated a small larynx with only the posterior arytenoids visualized.4 While our patient presented with normal laryngeal anatomy as seen in Figure 1C and D, this report demonstrates the utility of video laryngoscopy for intubation in patients with 4QDS. There was potential for difficulty intubating our patient, and the video laryngoscope allowed the anesthesiologist to assess this in real time.
In addition to airway management, the anesthesia team also administered a QL block in the setting of laparoscopic inguinal hernia repair as a component of a multimodal anesthetic technique for pain management. Advances in pediatric regional anesthesia have evolved as the prevalence of ambulatory pediatric surgery has also grown. With the association of opioid use and perioperative complications, regional anesthesia has proven to be a safe and effective form of pain control in the ambulatory pediatric surgery setting, while also minimizing the use of narcotics.7 When used in conjunction with Tylenol, as in our patient, this constitutes multimodal anesthetic technique, an approach with proven benefit in ambulatory pediatric patients.8 While there is a documented report of pain insensitivity in 4QDS9, our patient had previously demonstrated a response to painful stimuli in the setting of incarcerated inguinal hernia, which warranted the adoption of the regional anesthetic technique. The QL nerve block has demonstrated efficacy in multiple randomized control trials, presented by Zhao et al. in a meta-analysis of 346 patients, especially when administered under general anesthesia and ultrasound guidance.10 The uncomplicated nature of our patient’s nerve block, in addition to the lack of laryngeal narrowing seen during video-assisted intubation and the lack of persistent cardiac defects, suggest the variance in presentation/phenotype present in patients with 4QDS. This is also in line with the inconsistent reporting of both pain insensitivity and laryngeal narrowing reported in the literature.2,4,5,9Our approach, with emphasis on the ASA 2022 Guidelines, maximized patient safety by emphasizing teamwork, communication, and caution. Some limitations of this approach, though, include the resources and time required to successfully carry out this plan. Smaller institutions may not have access to pediatric video laryngoscopy or providers trained in the use of such equipment.