Laboratory tests to identify patients at risk of early major adverse events: a prospective pilot study.

BACKGROUND/AIMS: To test whether commonly measured laboratory variables can identify surgical patients at risk of major adverse events (death, unplanned intensive care unit (ICU) admission or rapid response team (RRT) activation). METHODS: We conducted a prospective observational study in a surgical ward of a university-affiliated hospital in a cohort of 834 surgical patients admitted for >24 h. We applied a previously validated multivariable model-derived risk assessment to each combined set of common laboratory tests to identify patients at risk. We compared the clinical course of such patients with that of control patients from the same ward who had blood tests but were identified as low risk. RESULTS: We studied 7955 batches and 73,428 individual tests in 834 patients (males 55%; average age 65.8 ± 17.6 years). Among these patients, 66 (7.9%) were identified as 'high risk'. High-risk patients were older (75.9 vs 61.8 years of age; P < 0.0001), had much greater early (48 h) mortality (6/66 (9%) vs 4/768 (0.5%); P < 0.0001) and greater overall hospital mortality (11/66 (16.7%) vs 9/768 (1.2%); P < 0.0001). They also had more early (8/66 (12.1%) vs 14/768 (1.8%); P = 0.0001) and overall in-hospital unplanned ICU admissions (12/66 (18.2%) vs 18/768 (2.3%); P < 0.0001) and more early (26/66 (39.3%) vs 50/768 (6.5%); P < 0.0001) and overall in-hospital RRT calls (26/66 (39.4%) vs 55/768 (7.2%); P < 0.0001). CONCLUSIONS: Commonly performed laboratory tests identify surgical ward patients at risk of early major adverse events. Further studies are needed to assess whether such identification system can be used to trigger interventions that help improve patient outcomes.

Postoperative hypothermia and patient outcomes after major elective non-cardiac surgery.

Using a multicentre adult patient database from Australia and New Zealand, we obtained the lowest and highest temperature in the first 24 h after admission to the intensive care unit after elective non-cardiac surgery. Hypothermia was defined as core temperature < 36 °C; transient hypothermia as a temperature < 36 °C that was corrected within 24 h, and persistent hypothermia as hypothermia not corrected within 24 h. We studied 50,689 patients. Hypothermia occurred in 23,165 (46%) patients, was transient in 22,810 (45%), and was persistent in 608 (1.2%) patients. On multivariate analysis, neither transient (OR = 1.07, 95% CI 0.96-1.20) nor persistent (OR = 1.50. 95% CI 0.96-2.33) hypothermia was independently associated with increased hospital mortality.

Postoperative hypothermia and patient outcomes after elective cardiac surgery.

Hypothermia after elective cardiac surgery is an important physiological abnormality and is associated with increased morbidity and mortality. The Australian and New Zealand intensive care adult patient database was studied to obtain the lowest and highest temperature in the first 24 h after surgery. Hypothermia was defined as core temperature < 36 °C; transient hypothermia as temperature < 36 °C that was corrected within 24 h; and persistent hypothermia as hypothermia that was not corrected within 24 h. Hypothermia occurred in 28,587 out of a total of 43,158 consecutive patients (66%) and was persistent in 111 (0.3%). Transient hypothermia was not independently associated with increased hospital mortality (OR = 0.9, 95% CI 0.8-1.1), whereas persistent hypothermia was associated with markedly increased risk of death (OR = 6.3, 95% CI = 3.3-12.0). Hypothermia is common in postoperative cardiac surgery patients during the first 24 h after ICU admission but, if transient, is not independently associated with an increased risk of death.

Diabetes and higher HbA1c levels are independently associated with adverse renal outcomes in inpatients following multiple hospital admissions.

OBJECTIVE: To assess the association between glycaemic status prior to the first hospital presentation with developing adverse renal outcomes overtime in patients with multiple hospital re-admissions. DESIGN: A prospective observational cohort study. PARTICIPANTS: All inpatients aged ≥54 years admitted between 2013 and 16 to a tertiary hospital. MAIN OUTCOMES: We prospectively measured HbA1c levels in all inpatients aged ≥54 years admitted between 2013 and 16. Diabetes was defined as prior documented diagnosis of diabetes and/or HbA1c ≥6.5% (47·5 mmol/L). Included patients had ≥ two admissions (at least 90 days apart), baseline estimated glomerular filtration rate (eGFR) >30 ml/min/1·73m2 and no history of renal replacement therapy. We assessed several renal outcomes: (a) 50% decline in eGFR; (b) rapid decline in renal function (eGFR decline >5 mL/min/1·73m2/year) and (c) final eGFR<30 ml/min/1·73m2. RESULTS: Of 4126 inpatients with a median follow-up of 465 days (254, 740), 26% had diabetes. The presence of diabetes was associated with higher odds of (a) 50% decline in eGFR (OR = 1·42;95% CI:1·18-1·70;p < 0·001); (b) rapid decline in renal function (OR = 1·40;95%CI:1·20-1·63;p < 0·001), and (c) reaching eGFR<30 ml/min/1.73m2 (OR = 1·25;95%CI:1·03-1·53;p < 0·05). Every 1% (11 mmol/L) increase in baseline HbA1c was associated with significantly greater odds of (a) >50% decline in eGFR (OR = 1·07;95% CI:1·01-1·4;p < 0·05) and (b) rapid decline in renal function (OR = 1·11;95% CI:1·05-1·18;p < 0·001). CONCLUSIONS: In patients with ≥two admissions, the presence of diabetes and higher HbA1c levels were strongly and independently associated with adverse renal outcomes at follow up. Such patients are at high risk of relatively rapid deterioration in renal function and a logical target for structured preventive interventions.

Inadvertent hypothermia and mortality in postoperative intensive care patients: retrospective audit of 5050 patients.

We proposed that many Intensive Care Unit (ICU) patients would be hypothermic in the early postoperative period and that hypothermia would be associated with increased mortality. We retrospectively reviewed patients admitted to ICU after surgery. We recorded the lowest temperature in the first 24 h after surgery using tympanic membrane thermometers. We defined hypothermia as < 36 degrees C, and severe hypothermia as < 35 degrees C. We studied 5050 consecutive patients: 35% were hypothermic and 6% were severely hypothermic. In-hospital mortality was 5.6% for normothermic patients, 8.9% for all hypothermic patients (p < 0.001), and 14.7% for severely hypothermic patients (p < 0.001). Hypothermia was associated with in-hospital mortality: OR 1.83 for each degree Celsius ( degrees C) decrease (95% CI: 1.2-2.60, p < 0.001). Given the evidence for improved outcome associated with active patient warming during surgery we suggest conducting prospective studies of active warming of patients admitted to ICU after surgery.

Routine use of HbA1c amongst inpatients hospitalised with decompensated heart failure and the association of dysglycaemia with outcomes.

Diabetes is an independent risk factor for development of heart failure and has been associated with poor outcomes in these patients. The prevalence of diabetes continues to rise. Using routine HbA1c measurements on inpatients at a tertiary hospital, we aimed to investigate the prevalence of diabetes amongst patients hospitalised with decompensated heart failure and the association of dysglycaemia with hospital outcomes and mortality. 1191 heart failure admissions were identified and of these, 49% had diabetes (HbA1c ≥ 6.5%) and 34% had pre-diabetes (HbA1c 5.7-6.4%). Using a multivariable analysis adjusting for age, Charlson comorbidity score (excluding diabetes and age) and estimated glomerular filtration rate, diabetes was not associated with length of stay (LOS), Intensive Care Unit (ICU) admission or 28-day readmission. However, diabetes was associated with a lower risk of 6-month mortality. This finding was also supported using HbA1c as a continuous variable. The diabetes group were more likely to have diastolic dysfunction and to be on evidence-based cardiac medications. These observational data are hypothesis generating and possible explanations include that more diabetic patients were on medications that have proven mortality benefit or prevent cardiac remodelling, such as renin-angiotensin system antagonists, which may modulate the severity of heart failure and its consequences.

Findings of the first ANZICS conference on the role of intensive care in Rapid Response Teams.

Rapid Response Teams (RRTs) are specialised teams introduced into hospitals to improve the outcomes of deteriorating ward patients. Although Rapid Response Systems (RRSs) were developed by the intensive care unit (ICU) community, there is variability in their delivery, and consultant involvement, supervision and leadership appears to be relatively infrequent. In July 2014, the Australian and New Zealand Intensive Care Society (ANZICS) convened the first conference on the role of intensive care medicine in RRTs in Australia and New Zealand. The conference explored RRSs in the broader role of patient safety, resourcing and staffing of RRTs, effect on ICU workload, different RRT models, the outcomes of RRT patients and original research projects in the area of RRSs. Issues around education and training of both ICU registrars and nurses were examined, and the role of team training explored. Measures to assess the effectiveness of the RRS and RRT at the level of health system and hospital, team performance and team effectiveness were discussed, and the need to develop a bi-national ANZICS RRT patient database was presented. Strategies to prevent patient deterioration in the 'pre-RRT' period were discussed, including education of ward nurses and doctors, as well as an overarching governance structure. The role of the ICU in deteriorating ward patients was debated and an integrated model of acute care presented. This article summarises the findings of the conference and presents recommendations on the role of intensive care medicine in RRTs in Australia and New Zealand.

Sodium and water regulation in a patient with cerebral salt wasting.

Hyponatremia, in patients with central nervous system disease, can be attributable to impaired free water excretion (syndrome of inappropriate secretion of antidiuretic hormone) or to excessive sodium excretion (cerebral salt wasting). We present a patient with a parietal glioma and hyponatremia characterized by salt wasting and dehydration. Rehydration and sodium repletion corrected the sodium and volume deficits; withdrawal of supplemental sodium resulted in recurrence of dehydration and hyponatremia. We determined sodium and water balance and measured plasma atriopeptin, antidiuretic hormone, and aldosterone. Plasma atriopeptin ranged from 8 to 44 pg/mL (normal, less than 45 pg/mL); antidiuretic hormone was not elevated at 4 to 5 pg/mL, and aldosterone was slightly elevated at 1040.25 pmol/L. The concentrations of these hormones could not directly explain the natriuresis; interactions with neural or other humoral factors may be involved. In evaluating such patients, careful attention to sodium and water balance is important to guide appropriate therapy.

Effect of a fecal bulking agent on diarrhea during enteral feeding in the critically ill.

Diarrhea is a common complication of enteral feeding in critically ill patients. This placebo-controlled clinical trial assessed the effect of adding fiber in the form of 'Fybogel' (Ispaghula husk), one sachet twice daily, on the occurrence of diarrhea during enteral feeding. Sixty-eight patients without prospectively defined exclusion criteria were enterally fed with 'Osmolite' in the Intensive Care Unit during the study period, 35 receiving 'Fybogel', and 33 placebo. Nineteen patients in each group had diarrhea on at least 1 day during enteral feeding, with 66 (23%) feeding days complicated by diarrhea in the 'Fybogel' group, and 68 (23%) in the placebo group. Narcotic infusions, thiopentone infusions, 'Mylanta', H2-antagonists, and nystatin suspension did not significantly affect the incidence of diarrhea. Weak correlations were found between diarrhea and the number of antibiotics each patient received (r = 0.2, p less than 0.05) and also the number of positive nonenteral bacterial cultures (r = 0.2, p less than 0.05). The addition of fiber in the form of 'Fybogel' to enteral feeds did not affect the occurrence of diarrhea.

Brain resuscitation. Medical management and innovations.

In this article, we have reviewed the pathophysiology and several therapeutic strategies for cerebral ischemia. It seems likely that there will never be simple therapeutic answers to the complex pathophysiology of cerebral ischemia as we now understand it. Ultimate therapies will probably involve combinations of interventions designed to block several ongoing pathophysiologic processes in neuronal death. Progress in this field will likely be slow and difficult.

Variability in adequacy of ventilation during transport of cardiac surgery patients: a cohort study.

Inadequate ventilation of intubated patients during transport from the operating theatre to the intensive care unit with attendant hypercarbia may adversely affect haemodynamics. In a retrospective observational study, we assessed the incidence of inadequate ventilation during transport from the operating theatre to the intensive care unit in 99 consecutive cardiac surgery patients admitted to our university tertiary hospital. Demographic, clinical, arterial blood gas and haemodynamic measurements were made on arrival in the intensive care unit after cardiac surgery. The relationships between arterial carbon dioxide tension (P(a)CO2), mean pulmonary artery pressure (MPAP) and other relevant haemodynamic variables were explored. Overall, hypocarbia (P(a)CO2 < 35 mmHg) occurred in 18.2% of patients, while 28.3% of patients had hypercarbia (P(a)CO2 > 45 mmHg). Pulmonary hypertension was common, with nearly half of the cohort having MPAP > or = 25 mmHg and 17.2% > or = 30 mmHg. However there was no association between P(a)CO2 and MPAP (R2 = 0.0076, P = 0.39). Contrary to expectation, neither hypercarbia nor high MPAP were associated with measured adverse outcomes, although this may have been because we studied an insufficient number of patients with extreme values. Associations of higher MPAP, which would be expected to compromise cardiovascular status, included acidaemia, hypoxia and the requirement for noradrenaline. These factors define a group of high-risk patients who should receive particular attention and who should be the focus of future studies.

A unique snapshot of intensive care resources in Australia and New Zealand.

The objective of this study was to analyse and report on the distribution and attributes of intensive care services in Australia and New Zealand for the 2005/2006 financial year A survey was mailed to 155 Australian and 26 New Zealand intensive care units (ICU) listed on the database of the Australian and New Zealand Intensive Care Society. A descriptive analytical approach was used. Of the 181 ICUs, 177 provided data. In Australia there were 100 public sector and 51 private sector ICUs and in New Zealand, 24 public sector and two private sector ICUs. These units contain 1485 available beds in the public sector and 538 available beds in the private sector Calculations to determine beds per 100,000 population, medical specialists per 1000 patient days and registered nurses per 1000 patient days showed wide variation. International comparisons are limited by lack of data; however it does appear that intensive care patients in Australia and New Zealand have very good outcomes.

Isolated ligamentous cervical spinal injury in the polytrauma patient with a head injury.

The evaluation of the cervical spine in the unconscious trauma patient is a difficult and controversial topic in trauma management. Conventional cervical clearance protocols consisting of plain radiology and computed tomography may not adequately detect unstable cervical ligament and disc injuries, even though a high-risk mechanism of injury has occurred. We present two cases where cervical clearance protocols, utilising plain X-rays and multi-slice computed tomography, failed to identify significant ligamentous spinal injuries. A delay in diagnosis or a missed spinal injury can lead to delays in treatment, thereby increasing the risk of neurological deterioration with the potential devastating sequela of quadriplegia. Therefore, in the unconscious trauma patient who, by definition, has sustained a high-risk mechanism injury, we routinely recommend the use of magnetic resonance imaging in addition to plain X-rays and computed tomography, to evaluate further discoligamentous status.

Error in medicine: adverse events in intensive care.

Human error occurs in all walks of life, including medicine. Numerous studies demonstrate that iatrogenic complications account for many deaths, long-term disabilities and unnecessary expense. The study of these adverse events can be formalized in various ways in order to minimise the frequency and severity of complications. Incident monitoring borrows its methodology from the well proven airline, scuba diving and similar fields where "near miss" events are treated as seriously as actual events, because the near miss is often a pointer to a systematic problem which should be corrected. The areas of human performance psychology and the analysis of complex systems are of increasing relevance to the avoidance of error. These techniques have been incorporated into the Australian Incident Monitoring Program which developed in the anaesthetic forum but which has now been taken up by intensive care units and indeed hospital wide in many parts of Australia and New Zealand.

Adverse incident reporting in intensive care.

This prospective, observational, anonymous incident reporting study aimed to identify and correct factors leading to reduced patient safety in intensive care. An incident was any event which caused or had the potential to cause harm to the patient, but included problems in policy or procedure. Reports were discussed at monthly meetings. Of 390 incidents, 106 occasioned "actual" harm and 284 "potential" harm. There was one death, 86 severe complications and 88 complications of minor severity. Most were transient but the effects of 24 lasted up to a week. Most incidents affected cardiovascular and respiratory systems. Incident categories involved drugs, equipment, management or procedures. Incident causes were knowledge-based, rule-based, technical, slip/lapse, no error or unclassifiable. The study has identified some human and equipment performance problems in our intensive care unit. Correction of these should lead to a reduction in the future incidence of those events and hence an increased level of patient safety.

Venous thromboembolism to the heart. A case report and review of treatment.

Venous thromboembolism to the heart is a rare and often fatal condition that is now being recognized more frequently owing to the widespread use of two-dimensional echocardiography. Death may be due to embolic obstruction of the tricuspid or the pulmonary valves, or to further migration of the embolus to the pulmonary arteries. The incidence of early recurrent pulmonary embolism is high. When used as primary treatment, medical treatment (anticoagulation or fibrinolytic therapy) failed in eight of 13 reported cases. Only one of eight patients died when surgical embolectomy was undertaken. We believe that an echocardiographic diagnosis of venous thromboembolism to the heart is sufficient evidence to warrant urgent surgical embolectomy. An undue delay in definitive treatment is often fatal.

Analgesia and sedation in interventional radiological procedures.

The use of intravenous analgesia and anxiolytics in interventional radiology improves the patient's tolerance of potentially painful and prolonged procedures and allows the radiologist better control of the course of the procedure being undertaken. Monitoring of the patient's oxygen saturation, pulse rate, respiration, blood pressure and cardiac rhythm during a procedure is essential. Fentanyl and midazolam is a combination that is effective and convenient to use because both agents are relatively short acting, have little cardiovascular depression and are easily reversible (with naloxone and flumazenil). They are a better alternative to pethidine and diazepam because they can be more tightly titrated and controlled and are safer and more suitable for use in outpatients. Monitoring for respiratory depression is important and special care must be taken in the elderly and patients with hepatic, renal or chronic airways disease. General anaesthesia may be unavoidable in patients who are unstable, unco-operative or who have raised intracranial pressure.

The Australian Incident Monitoring Study in Intensive Care: AIMS-ICU. An analysis of the first year of reporting.

The AIMS-ICU project is a national study set up to develop, introduce and evaluate an anonymous voluntary incident reporting system for intensive care. ICU staff members reported events which could have reduced, or did reduce, the safety margin for the patient. Seven ICUs contributed 536 reports, which identified 610 incidents involving the airway (20%), procedures (23%), drugs (28%), patient environment (21%), and ICU management (9%). Incidents were detected most frequently by rechecking the patient or the equipment, or by prior experience. No ill effects or only minor ones were experienced by most patients (short-term 76%, long-term 92%) as a result of the incident. Multiple contributing factors were identified, 33% system-based and 66% human factor-based. Incident monitoring promises to be a useful technique for improving patient safety in the ICU, when sufficient data have been collected to allow analysis of sets of incidents in defined "clinical situations".

Fulminant hepatic failure and fatal encephalopathy associated with Epstein-Barr virus infection.

A case of fulminant hepatic failure, associated with infectious mononucleosis, in a previously healthy 14-year-old girl is reported. Despite intensive therapy, which included the use of acyclovir, charcoal haemoperfusion, and measures to control her raised intracranial pressure (guided by serial EEG and auditory brainstem-evoked response recordings), the outcome was fatal.

Shift reagent enhanced concurrent 23Na and 1H magnetic resonance spectroscopic studies of transcellular sodium distribution in the dog brain in vivo.

The intracellular to extracellular sodium distribution is one of the primary determinants of action potentials necessary for the electrical function of organs such as brain, heart and skeletal muscle. The ability of shift reagent enhanced 23Na MRS to directly measure the intracellular and extracellular sodium distribution in brain is controversial and centers on the relative contributions of bulk magnetic susceptibility and hyperfine interactions to the observed chemical shifts. In this study, infusion of dysprosium (III) triethylenetetraminehexacetate (Dy(TTHA)-3), resulted in a 23Na MRS spectrum of dog brain with two well resolved peaks at 9 and 0.4 ppm. The 9 ppm peak corresponded to the resonance seen in aspirated blood. After disruption of the blood brain barrier, the single peak at 0.4 ppm split into two peaks at 3 and 0 ppm. The ability of Dy(TTHA)-3 enhanced 23Na MRS to follow global changes in brain sodium distribution was tested during cardiac arrest. The expected rapid Na influx into the intracellular space produced a marked decrease in the 3 ppm signal and a parallel increase in the 0 ppm peak. This is consistent with the assignment of the 3 ppm peak as interstitial sodium and the 0 ppm peak as intracellular sodium.