Abstract
Background:
Different discharge criteria are available for shifting patients out from postanesthesia care room following surgery. This study was done to compare the three-scoring system namely traditional time-based criteria, Fast track criteria and modified Aldrete score, in Indian population patients who recover after general anesthesia in postanesthesia care unit (PACU).
Materials and Methods:
Three hundred and seventy-five patients scheduled for general anesthesia were included in this study. Induction of anesthesia was done with intravenous (IV) propofol and maintained with sevoflurane inhalation with oxygen and nitrous oxide. Reversal of residual neuromuscular blockade was done with IV neostigmine and glycopyrrolate. Patients were shifted to PACU following tracheal extubation and recovery was assessed using the traditional time-based criteria, fast track criteria, and modified Aldrete score.
Results:
As per modified Aldrete score, mean time of shift out is 19 min with median of 15 min and standard deviation of 21.7 min. As per fast-track score, mean time of shift out is 187 min with median of 30 min and standard deviation of 243.7 min. As per the time-based criteria, mean time of shift out is 222 min with median of 240 min and standard deviation of 136.8 min. While using modified Aldrete score, majority of patients had a shorter stay in PACU and faster time to shift out as compared to fast-track criteria and traditional time-based criteria.
Conclusion:
Modified Aldrete score when compared to fast-track scoring and time-based criteria shows early recovery and reduces the length of stay in PACU.
Keywords: Fast track criteria, modified Aldrete score, postanesthesia care unit, postanesthesia discharge criteria, time-based discharge
Résumé
Contexte:
Différents critères de sortie sont disponibles pour faire sortir les patients de la salle de soins post-anesthésie après une intervention chirurgicale. Cette étude a été réalisée pour comparer le système de notation à trois, à savoir les critères traditionnels basés sur le temps, les critères accélérés et le score Aldrete modifié, en Inde. Population de patients qui se rétablissent après une anesthésie générale en unité de soins post-anesthésiques (USPA).
Matériels et méthodes:
Trois cent et soixante-quinze patients devant subir une anesthésie générale ont été inclus dans cette étude. L’induction de l’anesthésie a été réalisée par voie intraveineuse (IV) propofol et maintenu avec inhalation de sévoflurane avec de l’oxygène et du protoxyde d’azote. L’inversion du bloc neuromusculaire résiduel a été réalisée avec néostigmine IV et glycopyrrolate. Les patients ont été transférés vers une USPA après l’extubation trachéale et la récupération a été évaluée à l’aide du critères traditionnels basés sur le temps, critères accélérés et score d’Aldrete modifié.
Résultats:
Selon le score d’Aldrete modifié, temps moyen de sortie est de 19 min avec une médiane de 15 min et un écart type de 21,7 min. Selon le score accéléré, le temps moyen de sortie est de 187 minutes avec une médiane de 30 min et écart type de 243,7 min. Selon les critères temporels, le temps moyen de changement de poste est de 222 minutes avec une médiane de 240 minutes et écart type de 136,8 min. En utilisant le score d’Aldrete modifié, la majorité des patients ont eu un séjour plus court en USPA et un temps de changement plus rapide. Par rapport aux critères accélérés et aux critères traditionnels basés sur le temps.
Conclusion:
Score d’Aldrete modifié par rapport au traitement accéléré la notation et les critères basés sur le temps montrent une récupération précoce et réduisent la durée du séjour en USPA.
Mots-clés: Critères accélérés, score d’Aldrete modifié, unité de soins post-anesthésie, critères de sortie post-anesthésie, sortie basée sur le temps
INTRODUCTION
Developing countries such as India have been facing problems of increased patient load, lack of resources, workforce, and limitation of space increased the load on the postoperative intensive care unit (ICU) staff.[1] With the increasing trend of ambulatory anesthesia identifying criteria ensuring faster and safer discharge of the patients has become essential.[2]
The most crucial time in recovery is the one immediately following shifting the patient to postanesthesia care unit (PACU) as the patient needs to be monitored for recovery and can help in early detection of surgical complications.[3]
The most common scoring employed to test the discharge readiness from PACU is modified Aldrete score which does not consider the most common postoperative symptoms of pain, nausea, and vomiting, and hence, its efficacy as a scoring tool is being questioned. Therefore, a fast-track scoring consisting of all the elements of the modified Aldrete system, as well as an assessment of pain and emesis, has been employed.[4] However, in India, the traditional time-based discharge (TBD) criteria are widely used, where after a “fixed time interval” by anesthesiologists’ orders, patients are shifted out of the PACU.
There has not been enough literature on the factors determining the duration of postoperative ICU stay also not enough evidence is available on the application of appropriate discharge criteria in Indian settings. Moreover, not many studies have been done comparing the scoring criteria to test the recovery following general anesthesia, hence this study.
MATERIALS AND METHODS
This longitudinal, observational study was conducted at a tertiary care hospital in India after institutional ethics committee clearance and was registered under clinical trial registry of India (Trial number CTRI/2020/05/025195). Three hundred and seventy-five patients of American Society of Anesthesiologists (ASA) 1 and 2 over 18 years of age undergoing elective surgery under general anesthesia with estimated blood loss of <1 L during the procedure were included in this study. Written and informed consent was obtained from all the patients participating in the study. Thorough preanesthetic evaluation was performed, ASA grading, baselines vitals, and comorbidities were noted. Patients were premedicated with fentanyl (2 µ/kg) and midazolam (0.02 mg/kg) and induction was performed using intravenous propofol. Following neuromuscular blocker, tracheal intubation was carried out. Maintenance of anesthesia was done with oxygen, nitrous oxide, and sevoflurane inhalation. Neuromuscular blockade was reversed with neostigmine and glycopyrrolate. Time of intubation, type of airway device used, time taken from skin incision to closure, use of opioid, time of extubation, surgical complications, postoperative emetic use, and incidence of any critical event during surgery were documented. In the PACU, all patients were assessed using modified Aldrete score, fast-track criteria, and traditional time-based criteria at every 5 min until 30 min and then at 2, 6, 12, and 24 h posttracheal extubation. The time taken to reach a score of ≥9 according to modified Aldrete score and ≥12 according to fast track criteria was recorded.
Statistical analysis
IBM SPSS Statistics for Windows, Version 25.0. Armonk, NY: IBM Corp. were used to analyze the data. P < 0.05 was considered statistically significant and P < 0.001 was considered highly significant. Normal probability plots were used to examine the distribution of the variables. For quantitative variables with normal and nonnormal distribution, mean and median values were used. Qualitative variables were assessed using the Chi-square test and Fisher’s exact test. Intra-class correlation coefficient and Wilcoxon signed-rank test were used to find the agreement between the scoring criteria.
RESULTS
Most study participants were male (69.9%) posted for various surgical procedures. 50.9% of the patients had one or more comorbidities (ASA 2). Hypertension being the most common (114 subjects, 30.4%), followed by diabetes (113 subjects, 30.1%) being the second most common comorbidity.
The mean duration of the surgery, time of extubation, and time of PACU shift was calculated. The mean duration of the surgery was 85.9 ± 32.3 min, mean duration of extubation being 10.67 ± 3.88 min following cessation of anesthesia, and average time of PACU shift being 16.57 ± 4.6 min following extubation [Table 1].
Table 1.
Intraoperative surgical details
| n | Mean±SD | Minimum | Maximum | Percentiles |
|||
|---|---|---|---|---|---|---|---|
| 25th | 50th (median) | 75th | |||||
| Duration of surgery (min) | 375 | 85.91±32.315 | 15 | 120 | 60.00 | 90.00 | 120.00 |
| Time for extubation (min) | 375 | 10.67±3.881 | 5 | 20 | 10.00 | 10.00 | 15.00 |
| Time of PACU shift (min) | 375 | 16.57±4.689 | 5 | 30 | 15.00 | 15.00 | 20.00 |
SD=Standard deviation, PACU=Postanesthesia care unit
The mean and median of shift out time of patients from PACU according to modified Aldrete score, fast track score, and time-based criteria were analyzed. As per modified Aldrete score, mean time of shift out is 19 min with median of 15 min and standard deviation of 21.7. 25% patients had time of shift out ≤10 min and 25% patients had more than 20 min. As per fast-track score, mean time of shift out is 187 min with median of 30 min and standard deviation of 243.7 min. 25% patients had time of shift out less or equal to 15 min, 25% patients had more than 360 min. Five percentage of patients had time of shift out ranging from 16 to 360 min. As per the time-based criteria, mean time of shift out is 225.92 min with median of 240 min and standard deviation of 136.84 min. Twenty-five percentage of patients had time of shift out less or equal to 120 min, 25% patients had more than 240 min 50% of patients had time of shift out in the range of 120–240 min [Table 2].
Table 2.
Shift out time from postanesthesia care unit (min)
| n | Mean±SD | Minimum | Maximum | Percentiles |
|||
|---|---|---|---|---|---|---|---|
| 25th | 50th (median) | 75th | |||||
| Modified Aldrete score - time of shift out | 375 | 18.99±21.768 | 5 | 120 | 10 | 15 | 20 |
| Fast track score time of shift out | 375 | 187.53±243.738 | 5 | 900 | 15 | 30 | 360 |
| Time based criteria | 375 | 225.92±136.84 | 60 | 720 | 120 | 240 | 240 |
SD=Standard deviation
The median time of shift from PACU to ward according to modified Aldrete score was 15 min versus 30 min according to fast-track score and 240 min (4 h) according to time-based criteria. The study of normalcy in our study is by median values in this table [Table 3]. Intra-class coefficient was used to find the agreement between the modified Aldrete score and fast track [Table 4].
Table 3.
Agreement between modified Aldrete score and fast track criteria
| Fast track score time of shift out | Modified Aldrete score - time of shift out |
Total | |||
|---|---|---|---|---|---|
| 5–10 | 10–20 | 20–30 | 30–120 | ||
| 5–10 | 70 | 7 | 0 | 0 | 77 |
| 90.9% | 9.1% | 0.0% | 0.0% | 100.0% | |
| 47.3% | 3.9% | 0.0% | 0.0% | 20.5% | |
| 10–20 | 34 | 36 | 0 | 0 | 70 |
| 48.6% | 51.4% | 0.0% | 0.0% | 100.0% | |
| 23.0% | 20.0% | 0.0% | 0.0% | 18.7% | |
| 20–30 | 8 | 45 | 5 | 1 | 59 |
| 13.6% | 76.3% | 8.5% | 1.7% | 100.0% | |
| 5.4% | 25.0% | 16.1% | 6.3% | 15.7% | |
| 30–120 | 21 | 17 | 7 | 3 | 48 |
| 43.8% | 35.4% | 14.6% | 6.3% | 100.0% | |
| 14.2% | 9.4% | 22.6% | 18.8% | 12.8% | |
| >120 | 15 | 75 | 19 | 12 | 121 |
| 12.4% | 62.0% | 15.7% | 9.9% | 100.0% | |
| 10.1% | 41.7% | 61.3% | 75.0% | 32.3% | |
| Total | 148 | 180 | 31 | 16 | 375 |
| 39.5% | 48.0% | 8.3% | 4.3% | 100.0% | |
| 100.0% | 100.0% | 100.0% | 100.0% | 100.0% | |
Table 4.
Intraclass coefficient
| Intra-class correlation | 95% CI |
P | Level of Significance | |
|---|---|---|---|---|
| Lower bound | Upper bound | |||
| 0.124 | 0.074 | 0.285 | 0.101 | Not significant |
CI=Confidence interval
The difference between shift out time by modified Aldrete score and fast-track criteria was 15 min, which was found to be highly significant with a P = 0.00 [Table 5].
Table 5.
Comparison of shift out time of modified Aldrete score and fast track criteria
| Criteria | N | Mean | Standard Deviation | 50th (median) | IQR | Wilcoxon signed rank test (P) | Level of Significance |
|---|---|---|---|---|---|---|---|
| Modified Aldrete score - time of shift out | 375 | 18.99 | 21.77 | 15.00 | 10–20 | <0.001 | Highly significant |
| Fast track score time of shift out | 375 | 187.53 | 243.74 | 30.00 | 15–360 |
IQR=Interquartile range
On analyzing the association of fast-track score and time of shift out, patient variables such as comorbidities such as thyroid disorder, type of surgery, airway adjunct used, use of muscle relaxant, postoperative anti-emetic use, position of patient during surgery, duration of the surgery, time of extubation, and time of PACU shift was found to be highly significant while patient variables such as gender, ASA status, comorbidities such as diabetes, chronic kidney disease, emergency surgery, postoperative opioid use, was found to be significant in influencing the time to shift out. On the other hand, factors such as age, body mass index, comorbidities such as coronary artery disease, and asthma were found to be not significant [Table 6].
Table 6.
Test for significance
| Fast track score time of shift out with following parameters | Chi square/Fisher’s exact test (P) | Level of significance |
|---|---|---|
| Age | 0.088 | NS |
| Gender | 0.032 | Significant |
| ASA status | 0.018 | Significant |
| Diabetes | 0.043 | Significant |
| Hypertension | 0.409 | NS |
| Thyroid | 0.006 | HS |
| CAD | 0.840 | NS |
| Obesity | 0.172 | NS |
| Asthma | 0.903 | NS |
| CKD | 0.020 | Significant |
| BMI | 0.114 | NS |
| Emergency surgery | 0.031 | Significant |
| Elective surgery | 0.052 | NS |
| Type of surgery | 0.000 | HS |
| Airway | 0.001 | HS |
| Use of muscle relaxant | 0.000 | HS |
| Use of postoperative opioids | 0.010 | Significant |
| Use of postoperative antiemetic | 0.000 | HS |
| Position of the patient | 0.006 | HS |
| Duration of surgery | 0.000 | HS |
| Time for extubation | 0.000 | HS |
| Time of PACU shift | 0.000 | HS |
| Time based criteria | 0.000 | HS |
NS=Nonsignificant, HS=Highly significant, PACU=Postanesthesia care unit, BMI=Body mass index, CKD=Chronic kidney disease, CAD=Coronary artery disease, ASA=American Society of Anesthesiologists
DISCUSSION
Over the years, various discharge assessment tools have been devised to assess the recovery of patients and their discharge readiness from the PACU. There is little data on the comparison of these scoring criteria in low-income countries like India and it is essential to have an understanding how the scores are useful in our settings for timely transfer of patients from operation theater to PACU and to the ward. Therefore, we have compared the three scoring criteria, namely modified Aldrete score, fast-track score, and time-based criteria in our settings.
In this study, the average time of shifting from PACU using modified Aldrete score is (18.99 ± 21.76 min) and a median value of 15 min which is significantly shorter than the time of shifting using fast-track criteria (187 ± 243.73 min) with a median value of 30 min and using traditional time-based criteria (225.92 ± 136.84 min) with a median of 240 min. This demonstrated that patient’s discharge readiness using modified Aldrete score was significantly faster when compared to other two criteria. For this study we have used median as a test for normalcy. Though fast track score in addition takes into consideration the Post- operative nausea and vomiting (PONV) and postsurgical pain, it has a higher weightage in terms of documentation of adequate recovery.
From the current study, both fast-track criteria and modified Aldrete score appear to be better postoperative recovery tool when compared to traditional time-based criteria as it is a subjective criterion. Truong et al. conducted a study in 2004 comparing traditional time-based criteria with modified Aldrete scoring system in 292 consecutive individuals which showed patients assessed with clinical scoring system has significantly reduced length of PACU stay.[5] In the current study, the length of PACU stay according to traditional time-based criteria was significantly longer (240 min) when compared to the clinical scoring systems we employed (15 min and 30 min for Modified Aldrete score and Fast Track Criteria (MAS and FTC), respectively).
In a study conducted in Dallas in 1999 by White and Song studying 216 female patients for evaluation of recovery time in three separate groups (desflurane, sevoflurane and propofol), in propofol group when modified Aldrete score and fast-track score was compared, the mean difference in recovery time was 1.2 min.[4] Banerjee et al. performed a study in patients undergoing laproscopic surgeries in the Indian population comparing MAS and FTC which showed mean difference of time of recovery as 1.75 min.[1] The study by White and Song mostly consisted of patients undergoing tubal ligation, while the study by Banerjee et al. was comprised mostly of patients undergoing laparoscopic cholecystectomy. Our study consisted of wide spectrum of surgeries, including open and closed surgical approaches, laparotomy and laproscopic surgeries and surgeries belonging to different branches. The recovery profile in this variety of surgeries has not been carried out in previous studies. This implies the use of modified Aldrete score and fast-track scoring criteria as a discharge scoring system in PACU in spectrum of surgeries to achieve faster recovery, apart from fast tracking patients for ambulatory surgeries. This also signifies the applicability of these discharge criteria in different surgery types.
Our second objective of the study was to assess the factors affecting recovery after general anesthesia. Various studies have been conducted over years comparing the discharge scoring criteria and introduction of new discharge scoring criteria, but the factors influencing length of stay in PACU have received very little attention.[5]
In this study, when factors affecting recovery were assessed using modified Aldrete score, it was seen that old age significantly delayed recovery, which was seen in several recovery-based studies.[6,7,8,9] This is mainly due to the changes seen in metabolism in the elderly, which can lead to delay of recovery. We have seen that comorbidity like diabetes, hypertension, thyroid disorder, coronary artery disease, obesity significantly affected the recovery. The results were congruent with the study performed by Banerjee et al.[1] Patients belonging to ASA 2 category also showed delay in recovery.
We observed that increased duration of surgery influenced the emergence from anesthesia, leading to delayed recovery. Our observation was similar to various studies showing linear association of duration of surgery and recovery time.[1,6,8,9] Our study also demonstrated that time taken for extubation and time to shift to PACU also affected the recovery.
CONCLUSION
Adequate recovery is foremost in shifting the patient from the operation room to PACU and then to the ward. Modified Aldrete score when compared to fast-track scoring and time-based criteria shows early recovery and reduces the time of stay in PACU.
Financial support and sponsorship
Nil.
Conflicts of interest
There are no conflicts of interest.
Acknowledgment
We are extremely thankful to Kasturba Medical College, Mangalore and Manipal Academy of Higher Education, Manipal, Karnataka, India, for their support and guidance in conducting this study.
REFERENCES
- 1.Banerjee S, Kohli P, Pandey M. A study of modified aldrete score and fast-track criteria for assessing recovery from general anesthesia after laparoscopic surgery in Indian adults. Perioper Care Oper Room Manag. 2018;12:39–44. [Google Scholar]
- 2.Marshall SI, Chung F. Discharge criteria and complications after ambulatory surgery. Anesth Analg. 1999;88:508–17. doi: 10.1097/00000539-199903000-00008. [DOI] [PubMed] [Google Scholar]
- 3.Phillips NM, Haesler E, Street M, Kent B. Post-anaesthetic discharge scoring criteria: A systematic review. JBI Libr Syst Rev. 2011;9:1679–713. doi: 10.11124/01938924-201109410-00001. [DOI] [PubMed] [Google Scholar]
- 4.White PF, Song D. New criteria for fast-tracking after outpatient anesthesia: A comparison with the modified aldrete’s scoring system. Anesth Analg. 1999;88:1069–72. doi: 10.1097/00000539-199905000-00018. [DOI] [PubMed] [Google Scholar]
- 5.Truong L, Moran JL, Blum P. Post anaesthesia care unit discharge: A clinical scoring system versus traditional time-based criteria. Anaesth Intensive Care. 2004;32:33–42. doi: 10.1177/0310057X0403200106. [DOI] [PubMed] [Google Scholar]
- 6.Awad IT, Chung F. Factors affecting recovery and discharge following ambulatory surgery. Can J Anaesth. 2006;53:858–72. doi: 10.1007/BF03022828. [DOI] [PubMed] [Google Scholar]
- 7.Sinclair R. Delayed recovery of consciousness after anesthesia. Contin Educ Anesth Crit Care Pain. 2006;6:114–8. [Google Scholar]
- 8.Misal US, Joshi SA, Shaikh MM. Delayed recovery from anesthesia: A postgraduate educational review. Anesth Essays Res. 2016;10:164–72. doi: 10.4103/0259-1162.165506. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 9.Frost EA. Differential diagnosis of delayed awakening from general anesthesia: A review. Middle East J Anaesthesiol. 2014;22:537–48. [PubMed] [Google Scholar]