Prospective Evaluation and Analysis of Postoperative Admissions in the Intensive Care Unit of a Tertiary Care Hospital: An Indian Update

Vijay Singh; Rashmi Datta; Shibu Sasidharan; Lalit Tomar; M Babitha

doi:10.4103/jtccm.jtccm_6_20

ORIGINAL ARTICLE

Year : 2019 | Volume : 1 | Issue : 4 | Page : 127-134

Prospective Evaluation and Analysis of Postoperative Admissions in the Intensive Care Unit of a Tertiary Care Hospital: An Indian Update

Vijay Singh¹, Rashmi Datta², Shibu Sasidharan¹, Lalit Tomar³, M Babitha⁴
¹ Department of Anaesthesia and Critical Care, Level III IFH MONUSCO Hospital, Goma, DR Congo
² MG (Med), Delhi Area, New Delhi;, India
³ Department of Surgery, Level III IFH MONUSCO Hospital, Goma, DR Congo
⁴ Department of Radiodiagnosis, Ojas Hospital, Panchkula, Haryana, India

Date of Submission	05-Jun-2020
Date of Acceptance	20-Aug-2020
Date of Web Publication	31-Dec-2020

Correspondence Address:
Dr. Shibu Sasidharan
Department of Anaesthesia and Critical Care, Level III IFH MONUSCO Hospital, Goma, DR Congo, Goma
DR Congo

Source of Support: None, Conflict of Interest: None

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DOI: 10.4103/jtccm.jtccm_6_20

Abstract

Introduction: The characteristics for the planned ICU admissions were not surprising. However, the reasons for unplanned ICU admission are multi-factorial and may be beyond the scope of the anaesthesiologist's role in patient care. Unplanned intensive care admission may be a useful indicator of the quality of the overall process of peri-operative care. With this background, this study was undertaken to do a prospective evaluation, analysis of post-op admissions in the Intensive Care Unit of a tertiary care hospital. Material and Methods: The present observational study was conducted in the Intensive Care Unit of a defence Tertiary Care Hospital for a period of one-year wef 1Apr 18 to 31 March 19 and all the post-operative patients were divided into two groups: Group 1 – Planned Admissions: This included those patients where surgeon and/or the anaesthesiologist had decided pre-operatively for post-op ICU admission. Group 2 – Unplanned Admissions and Emergency admission: This included those patients, whose admissions were not anticipated pre-operatively, however, due to some unexpected peri-op complications arising within 48 hours of surgery led them to ICU admission. This group also comprised of patients who were admitted after forty-eight hours of primary surgery for post-operative complications. Result: In one year, the total operated patients (excluding paediatric, cardiac) in various OTs were 18157 and out of which, 261 patients were admitted to ICU. In planned group, maximum patients were of ASA III and in unplanned/emergency admissions ASA II patients were predominant. Post-operative gastrointestinal surgery patients formed a substantial percentage of the ICU admissions in both planned (94/211; 44.55%) and unplanned admission (20/50; 40.00%). GA with endotracheal intubation was technique of anaesthesia in both planned and unplanned admission. The predominant reason for unplanned ICU admission was post-operative care and treatment following unanticipated intra-operative complications. Conclusion: Thorough pre-operative evaluation and pre-operative optimization of patients whenever possible can reduce the incidence of unplanned admission to ICU. Early recognition of complications, timely intervention and timely intensive care and monitoring are essential to improve outcomes.

Keywords: Anesthesia, critical care, intensive care unit

How to cite this article:
Singh V, Datta R, Sasidharan S, Tomar L, Babitha M. Prospective Evaluation and Analysis of Postoperative Admissions in the Intensive Care Unit of a Tertiary Care Hospital: An Indian Update. J Transl Crit Care Med 2019;1:127-34

How to cite this URL:
Singh V, Datta R, Sasidharan S, Tomar L, Babitha M. Prospective Evaluation and Analysis of Postoperative Admissions in the Intensive Care Unit of a Tertiary Care Hospital: An Indian Update. J Transl Crit Care Med [serial online] 2019 [cited 2023 Mar 31];1:127-34. Available from: http://www.tccmjournal.com/text.asp?2019/1/4/127/305781

Introduction

The intensive care unit (ICU) is a special unit primarily concerned with the care of patients with acute, recoverable, life-threatening, critical illness, and injuries,^[1] which require constant close monitoring and support from specialized equipment and medications, i.e., continuous artificial ventilation, vasopressors, inotropes, and renal dialysis. Intensive care has been defined as a service for the patients with potentially recoverable life-threatening conditions who can benefit from more detailed surveillance and invasive treatment than provided in general wards or high dependency areas.^[2],[3] Adequate provision and more effective utilization of critical care resources are imperative for better outcome of high-risk surgical patients.^[4]

ICUs are the specialized inpatient units that provide care for the critically ill patients, but they are extremely expensive to operate, consuming 15%–40% of hospital costs despite comprising <10% of the inpatient beds.^{[2],[3],[5],[6],[7]} Most hospital ICUs operate with full capacity, making ICU beds a limited resource, which therefore must be streamlined effectively for the patients who deserve the most.^[7],[8] It is equipped with a vast array of up-to-date resources such as advanced monitors, organ support equipment, and highly skilled staff to achieve good outcome.^[9] Patients who undergo high-risk non-cardiac surgical procedures represent a large proportion of admissions to ICU. These are admitted to enable them to have any of a number of evidence-based interventions to improve their outcome and to prevent or rapidly treat complications. Ideally, surgeons, anesthesiologists, and intensivists admitting surgical patients to ICU target the patients who will benefit most from this highest level of ICU care. However, it is very difficult to identify such patients who are at risk of complications or death after major surgery.^[10],[11]

Postoperative outcomes are a result of the complex interplay between the anesthesia techniques, surgical procedure performed, the preanesthetic illness of the patient, and specific intra- and postoperative events. Variables associated with ICU admission include patient age, ASA physical status, whether or not a procedure was emergent, anesthesia duration, and certain types of surgeries and major surgeries.^{[5],[12],[13]} Postoperative outcomes may also be influenced by aspects of the particular health-care system, such as the surgical procedure volume at different hospitals,^[14] as well as care options, such as the availability and suitable use of intensive care beds. Appropriate triage of patients to intensive care postoperatively may have a large impact on outcomes after noncardiac surgery. Postoperative complications are important for both the patient and the health-care system. For the patients, these may result in significant morbidity and mortality with prolonged lengths of stay, repeated readmissions, and chronic ill health. For the organization, these can be an expensive problem to resolve.^[15]

An unplanned admission to an ICU within 48 h of surgery is an event that most patients and physicians would consider to be an important adverse outcome. It is a valuable screening tool to measure avoidable iatrogenic complications in surgical patients. Analysis of the incidence of unplanned postanesthetic and surgical admissions can provide an insight into the standard of perioperative management in operating theaters and ICU resource management.^{[13],[16],[17]} Unanticipated/unplanned postoperative ICU admission is generally taken as a quality control measure of overall perioperative anesthetic care. The reasons for unplanned ICU admission are multifactorial occurring in the intra- and postoperative period being an amalgamation of inherent risk factors surrounding a combination of coincidences and even misjudgments in the perioperative period. Many may be beyond the scope of the anesthesiologist's role in patient care.^[5],[12] Usually, prevention of complications starts in the preoperative period with evaluation of patient's disease and risk factors. However, identification and optimization of these unplanned postoperative ICU admission patients prior to surgical interventions remains difficult. With this background, this study was undertaken to do a prospective evaluation and analysis of postoperative admissions in the ICU of a tertiary care hospital and to formulate recommendations on the basis of the findings.

Materials and Methods

After the Hospital Ethical Committee approval, the present study was conducted in the ICU of a defense tertiary care hospital for a period of 1 year from April 1, 2018, March 31, 2019, and all the postoperative patients were divided into two groups:

Group 1 – Planned admissions: This included those patients who were admitted to the ICU postoperatively, where the surgeon and/or the anesthesiologist had decided preoperatively
Group 2 – Unplanned admissions and emergency admission: This included those patients whose admissions were not predicted preoperatively, however, due to some unexpected complications arising within 48 h in the perioperative period. Hence, ICU admission was required. This group also comprised those patients who were admitted to the ICU after 48 h of primary surgery for postoperative complications.

Inclusion criteria

All surgical patients admitted to the ICU from operating room who needed intensive observation, management, or monitoring in the postoperative period
All patients who needed ICU care in view of unexpected perioperative complications within 48 h of primary surgery
All patients with postoperative complications arising after 48 h of primary surgery.

Exclusion criteria

Patients already admitted in the ICU for any other surgical/medical problem and who were subsequently developed a surgical complication demanded surgery
Pediatric cases (<12 years of age) in view of separate pediatric ICU
Cardiac cases as these are regularly admitted to ICU postoperatively.

For analysis, the following factors were considered:

Preoperative variables: The following variables were included:

Age and sex of patients
Hemoglobin saturation
O2 desaturation preoperatively
Chronic obstructive pulmonary disease and other respiratory problem
Renal disease (creatinine >1.4)
Cardiac disease (valve lesion, angina, and infarct)
Other comorbidities (HTN, CVA, DM, and thyroid disorder)
HIV status
American Society of Anesthesiologists (ASA) physical status of the patient.

Intraoperative variables: The variables included in this are mentioned below:

Duration of anesthesia and surgery
Type of surgeries
Intraoperative desaturation (SpO₂ <90%)
Difficult intubation
Anesthesia technique
Intraoperative tachycardia (HR >120 beats/min for more than 10 min)
Intraoperative hypotension (blood pressure <80 mmHg for more than 15 min)
Intraoperative dysarrhythmias (new atrial fibrillation, Supra Ventricular Tachycardia (SVT), heart block, or premature ventricular contraction >5 min)
Intraoperative major blood loss (>1000 ml)
Intraoperative pulmonary edema.

Postoperative variables:

Total length of stay in ICU
Postoperative SpO₂ (<90%)
Postoperative ventilation
Blood transfusion
Use of inotropes and vasopressors
Inability to sustain head lift >5 s after extubation
Outcome of patients

Data analysis

Data analysis was done using IBM Statistical Package for the Social Sciences package version 20.0. Qualitative data variables were expressed using frequency and percentage. We also performed descriptive analysis with quantitative data variables and which were expressed as means and standard deviations.

Observation and Results

During the 1-year period, the total listed cases in various OTs were 17,617, cancelled cases 741, and unplanned or emergency cases were 1281. Emergency cases were mostly of gynecology and obstetrics, gastrointestinal surgery, neurosurgery, orthopedic surgery, and general surgery. Out of the total patients admitted in the ICU postoperatively, most of these had planned surgery (80.84%) and the incidence of unplanned admission to ICU in this study was 19.16%. There were predominant males (172 males vs. 89 females) and the mean age of the patients admitted in the ICU was 55.24 years and 53.175 years in planned and unplanned group, respectively. Distribution of cases is shown in [Figure 1].

Figure 1: Distribution of cases

Click here to view

In planned admissions (total 211), ASA III patients were 64.5% (136/211) and ASA II (21/50) were predominant in unplanned admission. The comparison of preoperative variables between planned and unplanned ICU admission is shown in [Table 1.

Table 1: Comparison of preoperative variables in planned and unplanned admission

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Postoperative gastrointestinal (GI) surgery patients formed a substantial percentage of the ICU admissions in both planned (94/211; 44.55%) and unplanned admission (20/50; 40%). GA with endotracheal intubation was technique of anesthesia in both planned and unplanned admission. The predominant reason for unplanned ICU admission was postoperative care and treatment following unanticipated intraoperative complications. The comparison of intraoperative variables between planned and unplanned admission is depicted in [Table 2].

Table 2: Comparison of intraoperative variables in planned and unplanned admission

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The maximum length of hospital stay was 2–4 days in 38.70% (101/261) of total postoperative ICU admissions and in planned group also maximum length of stay was 2–4 days in 40.30% (85/211) of patients. However, in unplanned group, maximum length of stay was 24–48 h in 40% (20/50) of patients. The mortality in our study was 16.48% (43/261) and 83.52% (218/261) were discharged to ward. The comparison of postoperative variables between planned and unplanned group is shown in [Table 3].

Table 3: Comparison of postoperative variables in planned and unplanned admission

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Discussion

Postoperative surgical patients continue to make up a substantial proportion of ICU admissions in most hospitals and these patients will get more benefit from thorough observation and management than provided in acute wards or high dependency areas.^[2],[3] In our institute, the mean age for planned and unplanned ICU admission was 55.24 ± 14.96 years, 53.175 ± 16.56 years, respectively, which is almost similar to Mohammed et al.'s study.^[18] However, this is slightly lower compared to other studies who have variously reported a mean age of 60 years^[19] and more than 60 years.^[20],[21] This discrepancy may be due to the institution being a service hospital, catering mainly to the younger serving persons. However, Ejiro et al. reported a mean age of 45 years, but their study had included postoperative pediatric patients.^[22]

In the present study, it was observed that as compared with the reference population, the rate of postoperative planned and unplanned ICU admission was higher in male patients. The reasons postulated for males having a greater risk are varied.^{[19],[22],[23]} The total number of minor gynecological operations (lasting for <30 min) performed in women of child-bearing age with no or minimal comorbidities form a substantial percentage of total operations done in female patients. Furthermore, men tend to suffer from more severe cardiac and pulmonary diseases as compared to premenopausal women and so may require more postoperative ICU observation.^[19]

In our study, there was a nearly equal distribution of postoperative ICU admissions in planned group with comorbidities (hypertension, Diabetes Mellitus (DM), Cerebro-Vascular Accident (CVA), thyroid disorder, and others) or without comorbidities taken collectively 51.20% and 48.80%, respectively. However, in the unplanned group, 60% (30/50) have no comorbidities and 40% (20/50) have comorbidities. Literature is scarce regarding the effect of preoperative comorbidities on ICU admissions.

Regarding the preoperative ASA class of the postoperative patients admitted to the ICU, a substantial percent of the patients 136 (64.45%) were ASA III in planned group. However, in unplanned ICU admissions, ASA II were more (41.30%) and causes of their admission to ICU were unanticipated blood loss, hypotension, tachycardia, dysarrhythmias, and pulmonary edema. Although some studies reported that elderly patients with poor physical reserves are more expected to have unplanned ICU admission,^[24],[25] our study does not support this conclusion. In the present study, the ASA status in the planned group was higher than unplanned group. This variation could be clarified on the fact that patients with higher ASA status like elderly patients with multiple diseases were already decided preoperatively by surgeon and/or the anesthesiologist to admit such patients in the ICU postoperatively, and unplanned group includes younger healthy patients who had an unanticipated perioperative complications which led them to unanticipated ICU admissions. In our study, 94.78% (200/211) and 82% (41/50) of patients were HIV negative in planned and unplanned groups, respectively, which was almost similar to Okoye et al.' study where the prevalence of HIV-negative patients was 96.3%.^[26]

In this study, it was observed that the mean duration of anesthesia in planned ICU admission (i.e., 80.84% of the total) was 4.90 h and 3.03 h for unplanned admissions (i.e., 19.16% of the total). Several studies have demonstrated greater perioperative risk with increase in the duration of surgery and hence the duration of anesthesia. Nevertheless, the risk predictive value of this factor is questionable.^[27] Duration of anesthesia may rather reflect the severity of the underlying surgical disease and the extent of surgical treatment that is needed. A longer duration of anesthesia due to a major surgery would imply a greater physiologic trespass and hence greater likelihood of adverse outcomes. The observation in this study was not in collaboration with the study by Satyawan et al.,^[19] who found that maximum number of patients (32.4%) had duration of anesthesia between 2 and 4 h. However, David et al. observed 220 min as the median operation length,^[28] which was almost similar to our study.

With respect to type of surgery, it was observed that maximum postoperative admissions in planned and unplanned were due to GI surgery (43.67%; 114/261). This observation was similar to other studies where maximum 74.5% of the total number of postoperative ICU admissions had underwent abdominal surgery.^[19],[29] In our study, this lower percentage of ICU admissions due to GI surgery could be explained due to organized laydown institutional practices. In our hospital, mostly, all postoperative neurosurgical patients (69/261; 26.43%) were admitted to ICU for observation rather than other type of surgery (excluding pediatric and cardiac surgery) as there was no separate neurosurgical ICU and this could have changed the overall statistics.

In the current study, the technique of anesthesia in 190 (72.79%) of the 261 patients admitted to the ICU in the postoperative period was general anesthesia with endotracheal tube (ETT), and GA with ETT with EA was anesthetic technique in 16.85% (44/261) of patients. Overall, the most common technique of anesthesia in planned and unplanned groups was GA with ETT, and in total, 88.65% (159 + 31 + 37 + 7 = 234) of patients had GA as a technique of anesthesia. Only 3 (1.14%) patients had been operated under local anesthesia, which included a burr hole surgery for subdural hematoma and two wound debridement of diabetic foot with multiple comorbidities. Among the rest, 6.51% (17/261) of patients received spinal anesthesia, 1.91% (5/261) was done under RA, and 1 (0.38%) each under epidural and TIVA. These findings almost correlated with the study of Satyawan et al. where 95.6% of patients operated with GA with ETT admitted to the ICU.^[19] Duncan et al. studied 100,000 anesthetic regimens and concluded that the choice of anesthesia did not provide any additional prognostic information for predicting mortality beyond that of patient disease and the surgical procedure.^[30] However, there are a series of randomized trials that has demonstrated an improved outcome with regional anaesthesia compared to general anesthesia.^{[19],[31],[32],[33]}

In the present study, it was observed that intraoperative oxygen desaturation (SpO₂ ≤90% for minimum 10 min) occurred in 4% of cases of unplanned cases, while in planned cases, only 1.90% had an intraoperative dip in saturation. On this issue, not much previous data are available. Michael and colleagues analyzed the various preoperative factors which could lead to intraoperative oxygen desaturation in ambulatory patients taken up for laparoscopic cholecystectomy and found a 1%–2% difference in patients with increased BMI and preoperative respiratory disorders.^[34] Other studies have attributed various other factors such as age, ASA physical status III, IV, and V, history of upper respiratory tract infection, history of asthma, general anesthesia and a duration of anesthesia more than 30 min as predictors to intraoperative desaturation.^[35],[36]

Out of the total 261 postoperative ICU admissions in the current study, 10.34% (27/261) had difficult intubation. On further analysis, a difficult intubation situation was encountered in 11.37% (24/211) of the planned admissions and 6.0% (3/50) of unplanned admissions. Unanticipated difficult airway, a common clinical problem encountered by all anesthesiologists, is probably the most important cause of major anesthesia-related morbidity.^[37] Various studies have published difficult intubation ranging from 3.67% to 7.6%.^{[38],[39],[40]} This higher incidence of difficult intubation in our study can be justified by the presence of higher number of patients with multiple comorbidities such as DM (known cause of difficult intubation) and differ in anesthesiologist's skill. Since this study was conducted in a tertiary level teaching hospital where many patients were anesthetized by junior faculty/residents, this factor has a bearing on the incidence of difficult intubation.

The characteristics for the planned ICU admissions were not surprising. In their preoperative evaluation, anesthesiologists/surgeon consider variables such as ASA physical status, comorbidities, anticipated major blood loss, anticipated duration of anesthesia, anticipated mechanical ventilation, and airway problems when determining the need for postoperative ICU admission.^{[2],[5],[19],[41]} However, the present study did not allow to assess the suitability of these conclusions. On the contrary, the reasons for unplanned ICU admission are multifactorial and may be beyond the scope of the anesthesiologist's role in patient care. Unplanned intensive care admission may be a useful indicator of the quality of the overall process of perioperative care. It was found in our study that, among the unplanned ICU admissions, 24% (12/50) cases were not reversed and shifted to ICU for postoperative ventilation who had multiple intraoperative surgical and anesthetic complications such as long duration of surgery, change of plan of surgery, difficult extubation, postoperative oxygen desaturation (SpO2 <90%), and failed reversal. In addition, 42% (21/50) of cases had intraoperative hemodynamic instability, out of which 24% (12/50) of patients were given blood transfusion. It was also observed that 11.87% (31/261) of patients had major blood loss (>1000 ml) intraoperatively who required blood transfusion in perioperative period. Out of this subset, 9% (19/211) of patients were planned and 24% (12/50) were unplanned ICU admissions. However, Kim et al.^[24] found that 38.4% of unplanned patients had transfusion during surgery and Miri et al. observed 39.9% of patients had required an intraoperative red cell transfusion.^[42]

In the present study, only two cases (4%) of pulmonary edema were observed as intraoperative period in unplanned group and both were occurred in younger patients. One case was of recurrent shoulder dislocation who underwent arthroscopic repair under GA developed negative pressure pulmonary edema on extubation and the second case was of pyelonephrosis with obstructive uropathy bilateral. Literature is scarce, directly linking intraoperative complications causing pulmonary edema. James et al. observed the incidence of postoperative pulmonary edema more in younger or pediatrics patients who underwent relatively minor, uncomplicated surgical procedure (mostly orthopedic surgery) under general anesthesia.^[43]

Postoperative complications were seen in both planned and unplanned cases. Oxygen desaturation was found in 7.30% 19/261 of patients. Out of 50 unplanned cases, there were 12 (24%) patients who had postoperative oxygen desaturation and 10 (20%) patients were unable to sustain head lift for more than 5 s. The institutional protocol was to give oxygen supplement and a repeat of reversal in all cases who experienced desaturation in the PACU. In the present study, it was found that the patients who were unable to sustain head tilt were more in the planned admission group, i.e., 77 (36.49%) as compared to unplanned group, i.e., 10 (20%) patients. The reason for this could be due to the presence of preoperative high ASA grade and preexisting multiple comorbidities in planned group as compared to unplanned group, which leads them to have decrease physiological reserve.

There is wide variation in the length of stay in the ICU for postoperative patients. In the current study, the maximum number of patients had ICU stay of 2–4 days, i.e., 38.70% (101/261), which correlated with Okafor et al.^[44] and Jacobson et al.'s^[45] studies. However, Satyawan et al. observed that the maximum percentage of patients had a length of stay <24 h.^[19] This difference was institutional based and depended on various protocols and standing orders of the particular hospital. It has been observed that long-term outcomes of patients in the term of 28 days' mortality, length of stay, and incidence of adverse events were worse for the unplanned than planned group.^[19],[46] However, in this study, a stay more than 7 days postoperative was maximum for planned admissions (7.60%, i.e., 16/211) as compared to unplanned admissions (2%, i.e., 1/50). This variation could be due to the occurrence of different ASA status, preoperative comorbidity, duration of surgery, and surgical difficulty between planned and unplanned group.

Additional observation in the current study was that 83.90% of planned admissions (177/211) were discharged to ward and in unplanned group 82% (41/50) discharged to ward. Mortality in planned group was 16.10% and in unplanned group was 18%. The overall mortality rate was 16.47% (43/261). Mortality rates reported in the literature again vary with rate of 14.5% reported by Piercy et al. in Australia^[20] to rates as high as 31% in a Nigerian study^[44] and 36% in a study from Mumbai, India.^[19]

Conclusion

Thorough preoperative evaluation and preoperative optimization of patients whenever possible can reduce the incidence of unplanned admission to ICU. Early recognition of complications, timely intervention, and timely intensive care and monitoring are essential to improve outcomes. Identification and optimization of these unplanned patients prior to surgical interventions remains difficult. ASA status level and unplanned ICU admission should also be routine variables in all anesthesia and surgical audits. Important factors for admission may be grouped into one of the following main categories: first, those that are present prior to surgery that include the comorbid status and age of the patient and the type and urgency of the surgery performed and second, the physiological derangement of the patient at the end of the surgical procedure. One strategy would be to admit all postoperative patients to an intensive care environment following surgery to enable them to have any of a number of evidence-based interventions in order to improve their outcome.

Limitation

Limitations of the current study include the fact that it was a single-center study. Moreover, the center itself was a tertiary care hospital which may not allow generalization to the other centers. This study has not included pediatric and cardiac patients due to separate ICU. Moreover, the period of the study was also 1 year, which was too small to get a general trend. However, the data can serve as a baseline data for comparison between centers and also in the future to assess if there are any changes in the trends of unplanned admissions to ICUs.

Recommendations

The following factors will be considered for the admission to ICU:

Age and sex: Elderly patients and male dominance
physical status
Type and nature of surgery: GI surgery and prolonged surgical time
Intraoperative variables: Major blood loss, difficult intubation and extubation, cardiac complication, periods of desaturation, hypotension, pulmonary edema.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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