Overview of the factors affecting outcomes of major head and neck surgery patients discharged to post-anesthesia care unit: 6-year retrospective analysis

Overview of the Factors Affecting Outcomes of Major Head And Neck Surgery Patients Discharged to Post-Anesthesia Care Unit: 6-Year Retrospective Analysis Melike Gençer Erkoç, Dokuz Eylül University, Department of Anesthesiology and Reanimation, Izmir, Turkey Aim: The incidence of head and neck cancer has been increasing in recent years and surgery constitutes a significant part of treatment options. It is important to identify preoperative determinants to improve postoperative results or to provide postoperative care opportunities. For these reasons, we aimed to determine the factors affecting postoperative outcomes by retrospectively examining the data of patients who had undergone major head and neck surgery in our clinic in the last six years and whose postoperative follow-up was performed in the post-anesthesia care unit (PACU). Materials And Methods: Our study retrospectively reviewed the data of major head and neck surgery patients who were discharged to PACU between the dates of 15.01.2014-15.01.2020 after obtaining the permission of the Dokuz Eylul University Non-Interventional Research Ethics Committee (decision number : 2019/29-21, date: 02.12.2019) . In our study, statistical analysis was done with SPSS program. Data receiving continuous values are expressed as mean ± standard deviation; continuous values of the subgroups were investigated using Kruskal Wallis, Mann Whitney U test, student t test or One-way ANOVA test taking into account the group number and normality results. Data indicating frequency are expressed as numbers and percentages; Fisher's exact test or chi-square test was used in the analysis of data indicating frequency in subgroups. A p value of less than 0.05 was considered as a significant difference. Correlation relationships between variables were determined using the Pearson Correlation Test. Results: A total of 74 major head and neck surgery cases were included in our study. It was determined that 37 (50%) of the patients were female, 37 (50%) were male and their mean age was 57.63 ± 15.93 years. The most common anatomic localizations of surgery were oral cavity-lip (41.9%), larynx (18.9%), thyroid-parathyroid (14.9%), hypopharynx (10.8%). ASA classifications of the patients were ASA-I 1.4%, ASA-II 48.6%, ASA-III 5 43.2% and ASA-IV 6.8%, and there was a significant relationship between the mean age increase and ASA score (p <0.001). The CCIs of the patients were calculated as 4.21 ± 1.58 on average. There was a statistically significant difference between CCI and ASA score and age (p <0.001). The most common comorbidities were hypertension (HT) (47.3%), chronic obstructive pulmonary disease (COPD) (24.3%) and diabetes mellitus (DM) (20.3%). In the Tumor-Node-Metastasis (TNM) classification, T4 (41.9%) and N0 (40.5%) stages were most common. The mean operation time was calculated as 517.14 ± 217.61 minutes. It was determined that operation time was increased with COPD (p = 0.045), free flap reconstruction (p <0.001) and tracheostomy requirement (p <0.001). The mean mechanical ventilation (MV) time is 18.69 ± 14.64 hours; There was a statistically significant relationship between preoperative sodium levels (r = -0,305, p = 0.011) and intraoperative blood transfusion (p = 0.014) with mechanical ventilation time. Increased need for intensive care (p = 0.034), blood transfusion (p = 0.009) and complications (p = 0.038) were observed in patients whose MV duration was over 24 hours. There was a statistically significant relationship between length of PACU stay with age over 60 years (p = 0.043), preoperative albumin level (r = -0.224, p = 0.042) and preoperative sodium level (r = -0.2554, p = 0.030), neutrophil-lymphocyte ratio (r = 0.223, p = 0.04), blood transfusion (p = 0.012) and MV time (r = 0.808; p <0.001). 6.8% of the patients needed intensive care unit admission and the mean length of intensive care stay was 11.2 ± 9.20 days. There was a statistically significant relationship between preoperative serum sodium levels (p = 0.042), operation time (p = 0.014), blood transfusion (p = 0.007), MV time (p = 0.002), length of PACU stay (p = 0.005) and intensive care unit admission. There was a statistically significant relationship between length of hospital stay and COPD (p = 0.033), crystalloid volume (r = 0.244; p = 0.036), operation time (r = 0.376; p = 0.001), tracheostomy (p <0.001), mechanical ventilation time (r=0,403; p=0,001), length of PACU stay (r = 0.266; p = 0.022), transfer to intensive care from PACU (p = 0.005), intensive care admission (p = 0.003). Complications were observed in 19 (25.7%) of the patients in our study. Being over 60 years of age (p = 0.032), COPD (p = 0.036), WBC count (p = 0.021), operation time (p = 0.018), tracheostomy (p = 0.008), transfer to intensive care from PACU (p = 0.015), intensive care admission (p = 0.001), length of hospital stay (p <0.001). Increased intraoperative crystalloid and colloid amount (p = 0.137; p = 0.060), prolonged operation time (p = 0.080), prolonged MV time (p = 0.060), increased complications (p = 0.063) were observed in the patients with in hospital mortality but it was not statistically significant. There is a statistically significant relationship between mortality and length of PACU stay (p = 0.045) and intensive care unit admission (p = 0.004). There was a statistically significant relationship between N stage and complications (p = 0.038), intensive care unit admission (p = 0.045) and mortality (p = 0.041). Conclusion: In order to evaluate the postoperative results in major head and neck surgery patients, patients should be considered from the preoperative period; electrolyte disorders and treatable conditions should be corrected. TNM staging should be evaluated, fluid and blood product treatments should be restricted in the intraoperative period, and postoperative effects of prolonged operation should be considered. It should be noted that intensive care unit may be needed with prolonged mechanical ventilation in the postoperative period and these conditions may be related to mortality. Keywords: Major head and neck surgery, postoperative outcomes, complication, mortality, post-anesthesia care unit, PACU