Criteria for intensive care unit admission and severity of illness

This article explores the provision and organisation of critical care services in the UK and examines the issues surrounding admission to, discharge from and the withholding of critical care.     

Criteria for intensive care unit admission and severity of illness

Intensive care is a specialist area of the hospital with concentration of resources and expertise to look after critically unwell patients. No set criteria exist for admission to intensive care, although patients usually have severe illness associated with physiological dysfunction and actual or impending organ failure. There are multiple scoring systems designed to assess severity of illness, all with significant limitations. The National Early Warning Score 2 (NEWS-2) is a commonly used ‘track and trigger’ system designed to detect and respond to the unwell or deteriorating patient. NEWS-2 is marker of physiological disturbance and high scores correlate with intensive care admission and mortality. Looking at the elective and emergency surgical population, patients at high risk of complications should be admitted to intensive care postoperatively. Increasing age, comorbidities, poor exercise tolerance and major surgical intervention are associated with adverse outcomes. Admission to intensive care often requires difficult time-critical decisions to be made with limited information. Intensive care admission can be the difference between life and death, but there are both physical and psychological harm associated with invasive organ support. The four pillars of medical ethics – autonomy, beneficence, non-maleficence and justice – can be used to guide these decisions.     

Severity of illness scoring systems and performance appraisal

A large number of severity of illness scoring systems have been developed and they are widely used in intensive care practice. However, they are complex systems with their basis in mathematics. To use such systems effectively, it is important to appreciate what factors influence their performance so that they can be compared fairly and used most appropriately. The purpose of this review is to describe the methods commonly used to assess the various facets of performance in severity of illness scoring systems. The performance of the most frequently used scoring systems in adult intensive care practice are presented. The shortfalls, misuse and strengths of scoring systems are also discussed.     

The Riyadh Intensive Care Program applied to a mortality analysis of a teaching hospital intensive care unit

A computerised system of prediction of death using the Riyadh Intensive Care Program was applied retrospectively over a 17-month period to data collected prospectively on 1155 patients admitted to our intensive care unit. Variables which enable organ failure scores to be generated were recorded daily to make these predictions. Consultant medical opinion predicted that outcome was hopeless in 55% (115/209) of the patients who died. The predictive power of the computer demonstrated a sensitivity of 14.8% and a specificity of 99.8%. It is possible that the occurrence of three false predictions of death in the latter part of the series may have been related to a change in our antibiotic policy. We would be unhappy to recommend the general use of a computerised program for prediction of death without careful explanation of its significance and dangers.     

Criteria for intensive care unit admission and the assessment of illness severity

Critical care expansion in the UK has increased in recent years, reflecting increased demand, yet bed occupancy remains high and there are significant difficulties in matching supply and demand. Expansion of ICU services outside the walls of critical care has involved the development of complex multidisciplinary outreach services who exist to support ward teams in caring for individuals who are critically unwell or have recently been stepped down from higher levels of care; there is increased evidence of their effectiveness in reducing mortality and preventing unexpected deterioration. Discharge of patients from critical care is also an area of controversy with conflicting evidence of increased mortality rates for those discharged prematurely or out-of-hours. Careful planning is involved with appropriate post-ICU care is critical to avoiding poor outcomes. ICU scoring systems allow comparison of outcomes between individual units and facilitate research but are unhelpful in predicting outcome for individual patients. Deciding which patients not to admit to ICU are frequently the most difficult decisions facing critical care staff. Many patients previously considered inappropriate for organ support may now be admitted pre-determined limits of treatment or to facilitate complex palliative care needs.     

胰岛素受体改变及血糖控制对危重症患者的影响

目的 探讨术后重症患者胰岛素受体的变化规律及严格血糖控制对其功能的影响.方法 以19例APACHEⅡ评分≥10分的术后重症患者为研究对象,根据血糖控制目标随机分为严格血糖控制组(控制血糖在4.4～6.7 mmol/L)和高血糖组(控制血糖在8.3～10.0 mmol/L).持续静脉泵入胰岛素控制血糖,记录血糖值和胰岛素用量.同时测定红细胞胰岛素受体(InsR)数目和亲和常数(K).结果 全部患者均出现血糖升高;术后第1天的红细胞胰岛素受体数目及亲和常数均明显低于正常,第2、4、7天逐渐恢复,但仍低于正常水平;APACHEⅡ评分≥15分者,第1天红细胞胰岛素受体数目、亲和常数明显低于APACHEⅡ评分＜15分的患者;平均每日胰岛素用量随红细胞胰岛素受体的恢复而逐渐减少,两者呈负相关;严格血糖控制组红细胞胰岛素受体数目和亲和常数的恢复明显好于高血糖组.两组间每日平均胰岛素用量无明显差异.结论 胰岛素受体的改变在应激性高血糖的发生中起一定作用,血糖正常化可能有助于胰岛素受体的恢复.     

A comparison of ICU mortality prediction using the APACHE II scoring system and artificial neural networks

The aim of this study was to compare the ability of artificial neural networks and the Acute Physiology and Chronic Health Evaluation II score to predict mortality in adult intensive care units. The same physiological variables were used in both predictive models to predict hospital mortality from a data set of 8796 patients collected from 26 adult intensive care units in the United Kingdom and Ireland as part of the Intensive Care Society study. The results from the two models were compared with the actual outcome. The overall prediction accuracy and the overall goodness-of-fit of all the models were assessed. Both predictive models showed similar goodness-of-fit and prediction discrimination. The overall predictive and classification performance of the artificial neural network developed matched and in some aspects was better than that of Acute Physiology and Chronic Health Evaluation II.     

The impact of Acinetobacter baumannii in the intensive care unit

Acinetobacter baumannii is a significant problem in critically ill patients. It is widespread, can colonise patients quickly and causes virulent infections. However, its overall impact on morbidity and mortality in the critically ill remains unmeasured. This study was designed to investigate A. baumannii colonisation and infection rates in a critically ill population over an 18-month period. Twenty-seven patients from a population of 347 were identified as having A. baumannii. Sixteen were colonised, whereas 11 were infected. Eleven of the 27 patients with A. baumannii died (41%). Of these, eight were colonised and three were infected. In the same period, 320 patients did not have A. baumannii and their mortality rate was 20% (n = 64). The mortality rate of patients with A. baumannii was significantly higher than that of patients without infection.     

Trauma patients in the intensive care unit: short- and long-term survival and predictors of 30-day mortality

BACKGROUND: The aims of this cohort study were to assess the survival of trauma patients treated in a general intensive care unit (ICU) and to evaluate the simplified acute physiology score (SAPS) II, maximum sequential organ failure assessment (SOFA) score, injury severity score (ISS), age, sex and severe head injury as predictors of 30-day mortality. METHODS: Three hundred and twenty-five adult patients admitted during 1998-2003 were evaluated retrospectively with update of survival data in January 2005. Kaplan-Meier statistics and Cox proportional hazards regression were used to study survival and to assess predictors of mortality, respectively. RESULTS: The 30-day mortality was 16.9%, ICU mortality 13.8% and hospital mortality 17.8%. Long-term survival (observation time, 1-7 years) was 77.8%. After 3.5 years, mortality was the same as for the background population. Severe head injury was the main cause of death and increased the risk of 30-day mortality 2.4-fold. In addition, SAPS II and an age above 50 years proved to be significant predictors of mortality in a multivariate analysis. Sex was not associated with mortality, and ISS and the maximum SOFA score were significant predictors in univariate analyses only. CONCLUSION: Reduced long-term survival was observed up to 3.5 years after acute injury. The 30-day mortality was strongly related to severe head injury, SAPS II and an age above 50 years. These variables may be useful as predictors of mortality, and may contribute to risk adjustment of this subset of trauma patients when treatment results from different centres are compared.     

The effect of nasotracheal intubation on the paranasal sinuses: A prospective study of 434 intensive care patients

A total of 434 patients admitted to the intensive care unit for mechanical ventilation were followed prospectively to investigate the influence of a nasotracheal tube on the paranasal sinuses. Twenty-five patients died before the examination was completed. The rest were examined for clinical symptoms of sinusitis. If sinusitis was suspected or the patients were intubated for 5 days or more, an x-ray of the sinuses was performed. In patients intubated for less than 5 days (N = 357), sinusitis was clinically suspected in three, but radiographically verified in only one. In patients intubated for 5 days or more (N = 47), 23 (49%) had affection of the paranasal sinuses. Patients needing a nasotracheal tube should be examined for sinusitis if they are intubated for more than 5 days or if unexplained fever, sepsis or purulent nasal secretion develops. If the suspicion is confirmed, the nasotracheal tube should be removed.     

Epidemiology and outcome analysis of 1359 intensive care burn patients: A 14-year retrospective study in a major burn center

AimsGlobally, burn-related morbidity and mortality still remain high. In order to identify regional high-risk populations and to suggest appropriate prevention measure allocation, we aimed at analyzing epidemiological characteristics, etiology and outcomes of our 14-year experience with an intensive care unit (ICU) burn patient population.MethodsA retrospective observational study was conducted including patients treated between March 2007 and December 2020 in our intensive care burn unit. Demographic, clinical and epidemiological data were collected and analyzed.ResultsA total of 1359 patients were included. 68% of the subjects were males and the largest age group affected entailed 45–64-year-old adults (34%). Regarding etiology, flame and contact burns were the most common in all age groups. Mean affected total body surface area (TBSA) was 13 ± 14.5% in all subjects. Most of the burns occurred domestically or during recreational activities. Mean hospital stay was 17.77 ± 19.7 days. The average mortality was 7.7%. The mortality rate showed an overall decreasing trend whilst burn severity remained consistent from 2007 to 2020.ConclusionsDespite consistent burn severity presentations of annual ICU admissions, burn injury mortality showed a decreasing trend, which was in part attributed to substantial progress in burn care and treatment and improved burn prevention awareness. Statistically significant age and gender differences could be detected with regard to burn etiology and seasonality, as well as outcomes, which highlight the importance of individualized primary prevention programs.     

Worthing physiological scoring system: derivation and validation of a physiological early-warning system for medical admissions. An observational, population-based single-centre study

Background: Several physiological scoring systems (PSS) have been proposedfor identifying those at risk of deterioration. However, thechosen specific physiological values chosen and the scores allocatedhave not been prospectively validated. In this study, we investigatethe relative contributions of the ventilatory frequency, heartrate, arterial pressure, temperature, oxygen saturation, andconscious level to mortality in order to devise a robust scoringsystem. All data were collected on admission to the emergencyunit. Precise ‘intervention-calling scores’ couldthen be derived to trigger interventions. Methods: Our observational, population-based single-centred study tookplace in a 602-bedded district general hospital. Patients admittedto the emergency care unit at Worthing general hospital duringan initial study period between July and November 2003 (n =3184) and a further validation period between October and November2005 (n = 1102) were included. Results: Multivariate logistic regression analysis demonstrated thata ventilatory frequency 20 min^–1, heart rate 102 min^–1,systolic blood pressure 99 mm Hg, temperature <35.3°C,oxygen saturation 96%, and disturbed consciousness were associatedwith an increase in mortality. The Worthing PSS was developedfrom the regression coefficients associated with each variable.The model showed good discrimination with an area under thereceiver operating characteristic curve, 0.74, excluding ageas a variable. The discrimination of this system was significantlybetter than the early-warning scoring system. Conclusions: A simple validated scoring system to predict mortality in medicalpatients with precise ‘intervention-calling scores’has been developed.     

The effect of dexmedetomidine on delirium and agitation in patients in intensive care: systematic review and meta-analysis with trial sequential analysis

Delirium is common in intensive care patients. Dexmedetomidine is increasingly used for sedation in this setting, but its effect on delirium remains unclear. The primary aim of this review was to examine whether dexmedetomidine reduces the incidence of delirium and agitation in intensive care patients. We sought randomised clinical trials in MEDLINE, EMBASE, PubMed and CENTRAL from their inception until June 2018. Observational studies, case reports, case series and non-systematic reviews were excluded. Twenty-five trials including 3240 patients were eligible for inclusion in the data synthesis. In the patients who received dexmedetomidine (eight trials, 1425 patients), delirium was reduced, odds ratio (95%CI) 0.36 (0.26–0.51), p < 0.001 and high quality of evidence. The use of dexmedetomidine was associated with a reduced incidence of agitation, OR (95%CI) 0.34 (0.20–0.59), p < 0.001, moderate quality of evidence. Patients who were randomly assigned to dexmedetomidine had a significantly higher incidence of bradycardia, OR (95%CI) 2.18 (1.46–3.24), p < 0.001, moderate quality of evidence; and hypotension, OR (95%CI) 1.89 (1.48–2.41), p < 0.001, high quality of evidence. We found no evidence of an effect on mortality, OR (95%CI) 0.86 (0.66–1.10), p = 0.23, moderate quality of evidence. The trial sequential analyses for the incidence of delirium, bradycardia and hypotension was conclusive but not for the incidence of agitation and mortality. In summary, this meta-analysis suggests that dexmedetomidine reduces the incidence of delirium and agitation in intensive care patients. The general quality of evidence ranged from moderate to high.     

The organisation of critical care for burn patients in the UK: epidemiology and comparison of mortality prediction models

In the UK, a network of specialist centres has been set up to provide critical care for burn patients. However, some burn patients are admitted to general intensive care units. Little is known about the casemix of these patients and how it compares with patients in specialist burn centres. It is not known whether burn‐specific or generic risk prediction models perform better when applied to patients managed in intensive care units. We examined admissions for burns in the Case Mix Programme Database from April 2010 to March 2016. The casemix, activity and outcome in general and specialist burn intensive care units were compared and the fit of two burn‐specific risk prediction models (revised Baux and Belgian Outcome in Burn Injury models) and one generic model (Intensive Care National Audit and Research Centre model) were compared. Patients in burn intensive care units had more extensive injuries compared with patients in general intensive care units (median (IQR [range]) burn surface area 16 (7–32 [0–98])% vs. 8 (1–18 [0–100])%, respectively) but in‐hospital mortality was similar (22.8% vs. 19.0%, respectively). The discrimination and calibration of the generic Intensive Care National Audit and Research Centre model was superior to the revised Baux and Belgian Outcome in Burn Injury burn‐specific models for patients managed on both specialist burn and general intensive care units.     

重症监护病房导管相关性尿路感染的影响因素及对院内感染的影响

目的探究重症监护病房导管相关性尿路感染的影响因素及对院内感染的影响。方法选取2018年6月至2019年10月本院收治的1128例重症患者,根据其是否发生导管相关性尿路感染分为观察组(65例)和对照组(1063例)。应用单因素分析及logistic回归分析重症患者导管相关性尿路感染的相关危险因素。结果1128例重症患者出现导管相关性尿路感染65例,发生率为5.76%(65/1128)。65例导管相关性尿路感染患者共分离病原菌79株。病原菌以革兰阴性菌为主,占43.04%(34/79);其次为真菌和革兰阳性菌,分别占25.32%(20/79)和24.05%(19/79)。两组合并糖尿病、住院时间、侵入性操作、留置导尿管时间及24 h尿量比较,差异均有统计学意义(P<0.05)。两组性别、年龄、体重指数(BMI)及合并高血压比较,差异均无统计学意义(P>0.05)。Logistic回归分析显示,合并糖尿病(OR=0.443,95%CI:0.228~0.860)、侵入性操作(OR=1.613,95%CI:1.163~2.104)、留置导尿管时间(OR=2.719,95%CI:2.314~4.106)、24 h尿量(OR=4.362,95%CI:1.974~10.915)是重症监护室患者发生导管相关性尿路感染的危险因素(P<0.05)。结论导管相关性尿路感染的危险因素包括合并糖尿病、侵入性操作、留置导尿管时间等。医务人员应采取相关措施以避免导管相关性尿路感染的发生,从而进一步减少医院感染。     

The effect of hospital volume on mortality and resource use after radical prostatectomy

PURPOSE: The value of radical prostatectomy for patients with prostate cancer depends on low morbidity and mortality. We assessed whether patient outcome is associated with how many of these procedures are performed at hospitals yearly. MATERIALS AND METHODS: Using the Nationwide Inpatient Sample, which is a stratified probability sample of American hospitals, we identified 66,693 men who underwent radical prostatectomy between 1989 and 1995. Cases were categorized into volume groups according to hospital annual rate of radical prostatectomies performed, including low-fewer than 25, medium-25 to 54 and high-greater than 54. We performed multivariate logistic regression to control for patient characteristics when assessing the associations of hospital volume, in-hospital mortality and resource use. RESULTS: Overall adjusted in-hospital mortality after radical prostatectomy was relatively low (0.25%). However, patients at low volume centers were 78% more likely to have in-hospital mortality than those at high volume centers (adjusted odds ratio 1.78, 95% confidence interval 1.7 to 2.6). Overall length of stay decreased at all hospitals between 1989 and 1995. However, average length of stay was longer and total hospital charges were higher at low than at high volume centers (7.3 versus 6.1 days, p<0.0001, and $15,600 versus $13,500, p<0.0001, respectively). CONCLUSIONS: Hospital volumes inversely related to in-hospital mortality, length of stay and total hospital charges after radical prostatectomy. Further study is necessary to examine the association of hospital volume with other important outcomes, including incontinence, impotence and long-term patient survival after radical prostatectomy.     

The effect of anemia and blood transfusions on mortality in closed head injury patients

BACKGROUND: The purpose of this study was to determine if anemia in isolated head trauma patients results in a higher mortality rate that would justify a more liberal use of blood transfusions. METHODS: A retrospective review of isolated blunt head trauma patients was performed between January 2001 and December 2006. Comparisons were made between survivors and nonsurvivors regarding demographics, laboratory values, transfusions received, and lengths of stay. RESULTS: There were 788 patients with 735 survivors who were significantly younger (46.3 y +/- 21.5 survivors versus 68.9 y +/- 18.8 nonsurvivors, P < 0.0001) and less injured [(ISS: 14.7 +/- 5.2 survivors versus 23.2 +/- 4.7 nonsurvivors, P < 0.0001), (head abbreviated injury severity: 3.7 +/- 0.7 survivors versus 4.7 +/- 0.5 nonsurvivors, P < 0.0001)] than those who died (n = 53). The survivors also had shorter lengths of stay (days) [(ICU: 2.4 +/- 4.2 versus 5.6 +/- 11.7, P = 0.03), (hospital: 6.3 +/- 9.8 versus 7.8 +/- 14.8, P = 0.02)]. Multivariate logistic regression showed age (OR 1.063, CI 1.042-1.084), ISS (OR 1.376, CI 1.270-1.491), minimum hemoglobin (OR 0.855, CI 0.732-1.000), and total blood products transfused (OR 1.073, CI 1.008-1.142) to be independent predictors of mortality with an ROC of 0.942. Outcome was independent of the operative procedures, hematocrit and packed red blood cells transfused at 24, 48, and 72 h. Hemoglobin levels of <8 mg/dL were more predictive of death than >8 mg/dL (P = 0.01). CONCLUSIONS: This study supports the need to balance mild anemia with judicious blood product use in the head trauma patient. Given the risk with blood product use, each transfusion should be carefully considered and the patient re-evaluated regularly to determine the need for further intervention.     

Prevalence,severity, and characteristics of medical device related pressure injuries in adult intensive care patients: A prospective observational study

This study was intended to determine the characteristics of Medical Related Pressure Injury (MDRPI) in adult intensive care patients. MDRIs are recognized as significant and complex health problems among hospitalized patients. Underestimated true scale of the problem is evident because the systematic clinical evaluation of MDRPI occurrence is not part of routine skin assessment among intensive care patients. A prospective approach was used to obtain data of MDRPIs with two weeks follow up to monitor the prevention and treatment strategies. Participants were 329 adult patients from three large referral and teaching centres in Jordan. Data were collected using a screening form that included demographic and clinical characteristics, and a list of medical devices. The primary outcome for this study was MDRPI and defined as a pressure injury (PI) found on the skin or mucous membrane with a medical device in use at the location of the injury (EPUAP, 2019). The patients with MDRPI were followed up for 2 weeks for prevention and treatment strategies. Prevalence of MDRPI was 5.01% (15/299) with 41 injuries, 27/41 (65.8%) were skin injuries and 14/41(34.2%) were mucosal. Most mucous membrane MDRPIs were at mouth/lips and caused by ET tube and meatal orifice caused by foley catheter. Skin MDRPIs were at the nose and caused by NG tube and hands by peripheral intravenous line and arms caused by blood pressure cuff. Inadequate prevention was provided on daily care as only 177 prevention and treatment interventions were provided over 2 weeks for 15 patients. As a growing problem among Jordanian adults in intensive care, MDRPI required the need for effective prevention. About one-thirds of MDRPIs were mucosal, a finding not previously reported, indicating the need to include mucous membrane assessment with skin assessment when a medical device such as NG and ET tubes or foley catheters are in use. Prevention and treatment interventions provided to patients with MDRPIs were not systematic and based on routine care with no clear guidelines. A consensus has yet to be reached suggesting the need to establish effective prevention strategies for medical device-related pressure injuries. Future research is recommended to follow up MDRPI prevention and treatment strategies among patients in ICU. We suggest to continue studying the prevalence of MDRPIs and monitoring the location, prevention and treatment of both skin and mucosal MDRPIs.