The Use of Vasopressor Agents in Free Tissue Transfer for Head and Neck Reconstruction: Current Trends and Review of the Literature

A Survey of Microvascular Technique Preferences Among American Head Neck Society Members

OBJECTIVE

To identify practices in microvascular techniques in routine and challenging scenarios.

STUDY DESIGN

Cross-sectional study.

METHODS

A national survey addressing practices related to microvascular free flap reconstruction was distributed to AHNS members between October and November 2021.

RESULTS

The respondents encompassed 95 microvascular surgeons. Median years of practice was 6 (interquartile range, 2-13) and median flaps per year was 35 (22-50). Common practices in arterial anastomosis included limited cleaning of artery (84.2%), use of a double approximating clamp (64.2%), and use of interrupted suture (88.4%). Common practices in venous anastomosis included limited cleaning (89.5%), downsizing the coupler (53.7%), and coupling to two independent venous systems (47.4%). In arterial anastomosis, respondents felt that kinking (50.5%) and tension (24.2%) were the riskiest challenges. Kinking was handled by loose sutures or native tissue/dissolvable biomaterial to orient pedicle. Excess tension was handled by additional dissection. With regards to associated practices, most surgeons perform anastomosis after partial inset (52.6%), give aspirin immediately postoperatively (66.3%), reserve transfusion for hemodynamic instability (69.5%), and utilize intraoperative pressors when needed (72.6%). More senior surgeons reported placing more suture to address leaks (p = 0.004) and perform end to side anastomosis on larger vein in case of venous mismatch (p = 0.012). In cases of tension, higher volume surgeons perform more extensive dissection (p = 0.035) and end to side coupling (p = 0.029).

CONCLUSIONS

This survey of AHNS members indicates patterns of microvascular techniques in routine and challenging scenarios. There exists a variation in approaches amongst surgeons based on volume and practice length.

LEVEL OF EVIDENCE

5 Laryngoscope, 134:1265-1277, 2024.

Opioid-Free Anaesthesia Reduces Complications in Head and Neck Microvascular Free-Flap Reconstruction

Head and neck free-flap microvascular surgeries are complex and resource-intensive procedures where proper conduct of anaesthesia plays a crucial role in the outcome. Flap failure and postoperative complications can be attributed to multiple factors, whether surgical- or anaesthesia-related. The anesthesiologist should ensure optimised physiological conditions to guarantee the survival of the flap and simultaneously decrease perioperative morbidity. Institutions employ different anaesthetic techniques and results vary across centres. In our institution, two different total intravenous approaches have been in use: a remifentanil-based approach and a multimodal opioid-sparing approach, which is further divided into an opioid-free anaesthesia (OFA) subgroup. We studied every consecutive case performed between 2015 and 2022, including 107 patients. Our results show a significant reduction in overall complications (53.3 vs. 78.9%, p = 0.012), length of stay in the intensive care unit (3.43 ± 5.51 vs. 5.16 ± 4.23 days, p = 0.046), duration of postoperative mechanical ventilation (67 ± 107 vs. 9 ± 38 h, p = 0.029), and the need for postoperative vasopressors (10% vs. 46.6%, p = 0.001) in the OFA group (vs. all other patients). The multimodal and OFA strategies have multiple differences regarding the fluid therapy, intraoperative type of vasopressor used, perioperative pathways, and various drug choices compared to the opioid-based technique. Due to the small number of cases in our study, we could not isolate any attitude, as an independent factor, from the success of the OFA strategy as a whole. Large randomised controlled trials are needed to improve knowledge and help define the ideal anaesthetic management of these patients.

Evaluating the impact of hemodynamic support measures on head and neck free tissue transfer outcomes: A population-based analysis

OBJECTIVES

This study sought to analyze the effects of perioperative blood transfusions and vasopressors on 30-day surgical complications and 1-year mortality after reconstructive surgery in head and neck free tissue transfer (FTT) and to identify predictors of administration of perioperative blood transfusions or vasopressors.

MATERIALS AND METHODS

TriNetX (TriNetX LLC, Cambridge, USA), an international population-level electronic health record database, was queried to identify subjects that underwent FTT requiring perioperative (intraoperative to postoperative day 7) vasopressors or blood transfusions. Primary dependent variables were 30-day surgical complications and 1-year mortality. Propensity score matching was used to control for population differences, and covariate analysis was used to identify preoperative comorbidities associated with perioperative vasopressor or transfusion requirements.

RESULTS

7,631 patients met inclusion criteria. Preoperative malnutrition was associated with increased odds of perioperative transfusion (p = 0.002) and vasopressor requirement (p < 0.001). Perioperative blood transfusion (n = 941) was associated with increased odds of any surgical complication (p = 0.041) within 30 days postoperatively and specifically increased odds of wound dehiscence (p = 0.008) and FTT failure (p = 0.002), respectively. Perioperative vasopressor was (n = 197) was not associated with 30-day surgical complications. Vasopressor requirement was associated with increased hazards-ratio of mortality at 1-year (p = 0.0031).

CONCLUSION

Perioperative blood transfusion in FTT is associated with increased odds for surgical complications. Judicious use as a hemodynamic support measure should be considered. Perioperative vasopressor use was associated with an increased risk of one-year mortality. Malnutrition is a modifiable risk factor for perioperative transfusion and vasopressor requirement. These data warrant further investigation to assess causation and potential opportunity for practice improvement.

Variations in Microcirculatory and Hemodynamic Parameters during Oncological Demolitive-Reconstructive Head and Neck Surgery: A Protocol for an Observational Study

(1) Background: Oncological demolitive-reconstructive surgeries in the head and neck region cause significant stress on patients' biohumoural, cardiac, and vascular systems, leading to disturbances in macrocirculatory and microcirculatory parameters. Traditional monitoring addresses the symptoms, but not the underlying cause. Microcirculatory assessments complement macrocirculatory monitoring, and bladder-catheter-based technology offers a better representation of central microcirculation. Flap reconstruction surgeries involve demolitive and reconstructive phases, requiring optimal tissue perfusion. The literature lacks a consensus on macro-microcirculation coupling, and there is no agreement on the use of vasopressors during head and neck surgeries. Evidence-based guidelines are lacking, resulting in variations in vasopressor administration. (2) Methods: This is a 12-month observational, prospective study conducted in a single center. It aims to evaluate the impact of macro-microcirculation coupling on clinical complications in head and neck surgery. All consecutive patients undergoing oncologic surgery requiring flap reconstruction and meeting the inclusion criteria will be enrolled. The study will utilize standard hemodynamic monitoring and bladder catheterization for measuring urine output and temperature. (3) Conclusions: The study aims to evaluate the coupling of macro- and microcirculation in head and neck surgeries, assess hemodynamic parameters and microcirculatory changes, and investigate their association with postoperative complications. The results can enhance patient care and surgical outcomes.

Evidence based recommendations for perioperative vasopressor use and fluid resuscitation in microsurgery

Blood pressure regulation is critical in patients undergoing microsurgical free tissue transfer; however, guidelines for addressing and preventing perioperative hypotension remain highly debated, with two current thought paradigms: (1) intravenous fluid administration with a balanced salt solution (e.g., lactate ringer and normal saline) and/or colloid (e.g., albumin) and (2) vasoactive pharmacological support with vasopressors (e.g., dobutamine, norepinephrine, epinephrine), with fluid administration being the preferred conventional approach. Here, we review the most up to date available literature and summarize currents perspectives and practices for fluid resuscitation and vasopressor use, while offering evidence-based guidelines to each.

Jaw-in-a-Riley-Day: Mandibular Free Flap Reconstruction With Virtual Surgical Planning in a Patient With Familial Dysautonomia

We present a unique case of mandibular reconstruction using virtual surgical planning (VSP) of a post-traumatic mandibular non-union defect for a patient with familial dysautonomia (FD), also known as Riley-Day Syndrome. In this case, the complexity related to perioperative and surgical challenges illustrates the utility of VSP and the importance of multi-disciplinary collaboration in jaw-free flap reconstructive surgery. We highlight our experience with the “Jaw-In-A-Day” approach in conjunction with tailored preoperative planning and perioperative care resulting in successful mandibular free flap reconstruction.

Anaesthesia for reconstructive free flap surgery for head and neck cancer

Head and neck cancer surgery presents significant challenges for the anaesthetist. A thorough multidisciplinary preoperative assessment and optimisation of the patient is essential, including nutritional and psychological evaluation. The incidence of a difficult airway is high, and the anaesthetist must be skilled in advanced airway techniques. Surgery is extensive, often requiring reconstructive surgery with either a pedicled or free flap. Detailed knowledge of flap physiology and anatomy is needed, and anaesthesia comprises careful management of mean arterial pressure, fluid administration, temperature control and oxygenation. The Enhanced Recovery after Surgery Society and the Society for Head and Neck Anaesthesia consensus recommendations provide guidance on current best practice. Despite continued debate, it now appears that this constitutes goal-directed fluid therapy, coupled with judicious vasopressor therapy sufficient to achieve an adequate mean arterial pressure. Emerging techniques such as prehabilitation and postoperative near-infrared spectroscopy flap monitoring provide hope of improved outcomes going forward.

Liberal versus Modified Intraoperative Fluid Management in Abdominal-flap Breast Reconstructions. A Clinical Study

Background:

The outcome of reconstructive microsurgery is influenced by the intraoperative anesthetic regimen. The aim of this study was to compare the impact on the intra- and postoperative complication rates of our modified fluid management (MFM) protocol with a previously used liberal fluid management protocol in abdominal-flap breast reconstructions.

Methods:

This retrospective study analyzed adverse events related to secondary unilateral abdominal-flap breast reconstructions in two patient cohorts, one with a liberal fluid management protocol and one with a MFM protocol. In the MFM protocol, intravenous fluid resuscitation was restricted and colloid use was minimized. Both noradrenaline and propofol were implemented as standard in the MFM protocol. The primary endpoints were surgical and medical complications, as observed intraoperatively or postoperatively, during or shortly after the hospital stay.

Results:

Of the 214 patients included in the study, 172 patients followed the MFM protocol. Prior radiotherapy was more frequent in the MFM protocol. Surgical procedures to achieve venous superdrainage were more often used in the MFM cohort. Intraoperative as well as postoperative complications occurred significantly more frequently in the liberal fluid management cohort and were specifically associated with partial and total flap failures. Prior radiotherapy, additional venous drainage, or choice of inhalation agent did not have an observable impact on outcome.

Conclusions:

The incidence of adverse events during and after autologous breast reconstructive procedures was reduced with the introduction of an MFM protocol. Strict intraoperative fluid control combined with norepinephrine and propofol was both beneficial and safe.