Postoperative Intensive Care Unit Patients Research Articles

The prevalence of long QT interval in post-operative intensive care unit patients.

The severity of patient illnesses and medication complexity in post-operative critically ill patients increase the risk for a prolonged QT interval. We determined the prevalence of prolonged QTc in surgical intensive care unit (SICU) patients. We performed a prospective cross-sectional study over a 15-month period at a major academic center. SICU pre-admission and admission EKGs, patient demographics, and laboratory values were analyzed. QTc was evaluated as both a continuous and dichotomous outcome (prolonged QTc>440ms). 281 patients were included in the study: 92% (n=257) post-operative and 8% (n=24) non-operative. On pre-admission EKGs, 32% of the post-operative group and 42% of the non-operative group had prolonged QTc (p=0.25); on post-admission EKGs, 67% of the post-operative group but only 33% of the non-operative group had prolonged QTc (p<0.01). The average change in QTc in the post-operative group was +30.7ms, as compared to +2ms in the non-operative group (p<0.01). On multivariable adjustment for long QTc as a dichotomous outcome, pre-admission prolonged QTc (OR 3.93, CI 1.93-8.00) and having had an operative procedure (OR 4.04, CI 1.67-9.83) were associated with developing prolonged QTc. For QTc as a continuous outcome, intra-operative beta-blocker use was associated with a statistically-significant decrease in QTc duration. None of the patients developed a lethal arrhythmia in the ICU. Prolonged QTc is common among post-operative SICU patients (67%), however lethal arrhythmias are uncommon. The operative experience increases the risk for long QTc.

Effectiveness of single dose conivaptan for correction of hyponatraemia in post-operative patients following major head and neck surgeries.

Background and Aims:Conivaptan, a vasopressin receptor antagonist, is commonly used for the treatment of euvolaemic, hypervolaemic hyponatraemia. Usually, an intravenous (IV) bolus followed by infusion is administered for many days. We decided to assess the effectiveness of single dose conivaptan for correction of hyponatraemia in post-operative patients.Methods:This was a prospective, randomised trial conducted in 40 symptomatic post-operative Intensive Care Unit (ICU) patients with a serum sodium level of ≤130 mEq/L. Group A patients received IV conivaptan 20 mg over 30 min, whereas in group B infusion of 3% hypertonic saline was started as an infusion at the rate of 20–30 ml/h. Serum sodium levels were measured at 12, 24, 48 and 72 h and the daily fluid balance was measured for 3 days. The Chi-square test, Wilcoxon signed rank test and Mann-Whitney tests were used as applicable.Results:The serum sodium levels before initiating treatment were comparable between groups. However, subsequent sodium levels at 12, 24 and 48 h showed significantly high values in group A. Though at 72 h the mean sodium value was high in group A, it was not statistically significant. Group A showed a significantly high fluid loss on day 1, 2 and 3. The mean volume of hypertonic saline required in group B showed a steady decline from day 1 to 3 and only 13 patients required hypertonic saline on the 3rd day.Conclusion:Single dose conivaptan is effective in increasing serum sodium levels in post-operative ICU patients up to 72 h associated with a significant negative fluid balance.

Role of procalcitonin in guiding antibiotic therapy

The role of procalcitonin in guiding antibiotic therapy is reviewed. Procalcitonin is a prohormone for calcitonin, which is secreted by the parafollicular cells of the thyroid gland. The biological activity of procalcitonin is significantly different from calcitonin and is believed to be part of the complex inflammatory cascade of the immune system. Procalcitonin has been shown to be elevated in bacterial infections but not in viral infections or other inflammatory conditions. The first published study that suggested that procalcitonin levels increased in the presence of bacterial infection was conducted in France in the early 1990s. Numerous studies have been conducted using procalcitonin-guided therapy to reduce antibiotic use. These studies were performed in one of three clinical settings: outpatient primary care (two multicenter, noninferiority studies of patients with upper- and lower-respiratory-tract infections), emergency room and inpatient (five studies in patients with chronic obstructive pulmonary disease, exacerbation, bronchitis, or community-acquired pneumonia), and the intensive care unit (ICU) (two studies in medical ICU patients and two in postoperative ICU patients with infection or sepsis). Based on the findings of these studies, a cutoff value of 0.25 μg/L in non-ICU patients or of 0.5 μg/L in ICU patients seems appropriate for making a decision about the initiation and discontinuation of antibiotic therapy. In patients with a significantly elevated baseline procalcitonin level, a subsequent drop of >80% appears to be reasonable for discontinuing antibiotics. Published evidence supports the use of procalcitonin as a biomarker of bacterial infection that can be used to reduce antibiotic exposure.

Low-Dose Remifentanil Infusion during Ventilator Weaning and Tracheal Extubation in Postoperative Intensive Care Unit Patients Sedated with Propofol-Remifentanil: A Randomised Clinical Trial

Discontinuation of sedatives for ventilator weaning and extubation can be associated with hyperdynamic responses, including hypertension and tachycardia. We examined the effects of a maintained low dose of remifentanil infusion on cardiovascular responses and coughing during extubation in postoperative intensive care unit patients sedated with propofol-remifentanil. Fifty patients who required mechanical ventilation after major abdominal surgery were randomised into remifentanil group (n=25) or control group (n=25). Sedation during mechanical ventilation was maintained with remifentanil and propofol via a target-controlled infusion system. These drugs were titrated to the target sedation range, bispectral index values of 60 to 75 and Richmond Agitation Sedation Scale values of -3 to -2. When weaning was initiated, propofol was stopped in both groups. In the control group, remifentanil infusion was also stopped; in the remifentanil group, remifentanil infusion was maintained until extubation at a target effect site concentration of 1.0 ng/ml. Extubation was performed if the patient's respiratory, haemodynamic states were stable and if the patient was able to follow commands. Heart rate, mean arterial pressure and cough severity were evaluated. The mean arterial pressure, heart rate and cough severity did not differ between the two groups during extubation. The time from stopping of propofol infusion to extubation was significantly longer in the remifentanil group compared to that in the control group (P=0.020). Maintaining a low-dose remifentanil infusion during ventilator weaning, delayed tracheal extubation without any differences in haemodynamic changes or coughing in postoperative intensive care unit patients.

The effect of music on discomfort experienced by intensive care unit patients during turning: A randomized cross‐over study

Research consistently demonstrates that intensive care unit (ICU) patients experience pain, discomfort and anxiety despite analgesic and sedative use. The most painful procedure reported by critically ill patients is being turned. Music diminishes anxiety and discomfort in some populations; however, its effect on critically ill patients remains unknown. This research aimed to identify the effect of music on discomfort experienced by ICU patients during turning using a single blind randomized cross-over design. Seventeen post-operative ICU patients were recruited and treatment order randomized. Discomfort and anxiety were measured 15 min before and immediately after two turning procedures. Findings indicated that listening to music 15 min before and during turning did not significantly reduce discomfort or anxiety. Pain management might effectively be addressing discomfort and anxiety experienced during turning. Given previous studies have identified turning as painful, current results are promising and it might be useful to determine if this is widespread.

What Is a NICE-SUGAR for Patients in the Intensive Care Unit?

What Is a NICE-SUGAR for Patients in the Intensive Care Unit?

Ascorbic Acid in Postoperative Intensive Care Patients - Biochemical Aspects and Clinical Experience

The transport mechanisms of ascorbic acid (AA) are described. The metabolism of AA and its function as an antioxidant are covered in some detail. Subsequently, indications for postoperative substitution are discussed. The supplementation of up to 300 mg of AA per day in postoperative intensive care unit patients during par-/enteral nutrition is recommended to prevent hypovitaminosis. It is not clear if this is the optimal dosage of AA in postoperative/-trauma patients. New aspects for an AA substitution are discussed.

Weaning Approach with Weaning Index for Postoperative Patients with Mechanical Ventilator Support in the ICU

S 47 Background: The weaning index is a useful tool for avoiding the detrimental consequences of weaning failure, rapidly identifying patients who are potentially ready for spontaneous breathing, and accelerating the process of liberation from mechanical ventilation. This study examined the use of the weaning index as a weaning and extubation predictor in postoperative patients on mechanical ventilatory support in an intensive care unit (ICU). Methods: Mechanical ventilation was discontinued in patients through pressure support ventilation (PSV), and a T-piece was applied to 169 patients. The success or failure of the weaning process was evaluated according to the preoperative conditions of the patient and their weaning indices, such as the rapid shallow breathing index (RSBI), vital capacity, inspiratory pressure. The duration of mechanical ventilation and the length of stay in the ICU and the hospital were recorded. Results: Weaning from mechanical ventilatory support and extubation was performed successfully in 94.6% of patients. Sixty minutes after applying the T-piece, the PaO2/FiO2 ratio (P/F ratio) was significantly higher and the RSBI was significantly lower in the weaning success group than in the weaning failure group. The ASA class and the percentage of emergency procedures were significantly lower (p ＜ 0.05) in the weaning success group. Conclusions: Not only the weaning index as RSBI but also P/F ratio, ASA class and emergency status need to be considered for successful weaning and extubation in postoperative ICU patients on mechanical ventilator support. (Korean J Anesthesiol 2007; 53: S 47～51)

Intensive Insulin Therapy in Postoperative Intensive Care Unit Patients: A Decision Analysis

Intensive Insulin Therapy in Postoperative Intensive Care Unit Patients: A Decision Analysis

Intensive Insulin Therapy in Postoperative Intensive Care Unit Patients

Intensive insulin therapy (IIT) may reduce mortality in mechanically ventilated postoperative patients. To assess the risks and benefits of IIT in different institutions. Retrospective, blinded-to-outcome selection of patient cohorts from four hospitals. Selection of a cohort of patients with clinical features similar to those reported in a recent study of IIT and of all mechanically ventilated postoperative patients from each hospital. Retrieval of information on glucose control. Assessment of risks and benefits and final outcomes. We selected 783 consecutive patients with similar clinical and demographic features to the IIT trial control group and four general cohorts for a total of 4,150 consecutive mechanically ventilated postoperative patients. In these patients, glucose levels were measured 212,663 times for a mean value of 8.22 +/- 2.7 mmol/L (148 +/- 49 mg/dl). Intensive care unit (ICU) mortality varied from 2.2 to 13.6%. The incidence of hypoglycemia (defined as < 2.2 mmol/L) varied from 1.4 to 2.7%. Assuming a beneficial effect of IIT as reported, the number needed to treat to save one life varied from 38 in one ICU to 125 in another, whereas the rate of hypoglycemia (number needed to harm) varied from 7 to 13. The number needed to treat to prevent an ICU death and the associated risk of hypoglycemia (number needed to harm) with IIT vary widely according to baseline mortality, case mix, and case selection. Rational decision analysis in individual ICUs should take these factors into account.

Remifentanil versus fentanyl for short‐term analgesia‐based sedation in mechanically ventilated postoperative children

Analgesia-based sedation techniques are becoming more established in the intensive care unit (ICU) setting. The aim of this study was to compare remifentanil and fentanyl infusions for postoperative analgesia in pediatric ICU patients. After receiving ethical committee approval, a prospective randomized, double-blind study was performed. Twenty-two postoperative orthopedic surgery patients received either remifentanil 0.1 microg.kg(-1).min(-1) or fentanyl 0.025 microg.kg(-1).min(-1) infusions diluted to the same volume. Analgesic infusion was titrated to predefined levels of analgesia [behavioral pain scale (BPS) score of 3]. Propofol was added if sedation was unsatisfactory after BPS score 3 had been achieved. There were no differences in groups regarding demographics, tracheal extubation times, and pain scores of the patients. After cessation of the opioid infusion, the sedation scores and the heart rates were always higher in the remifentanil group compared with the fentanyl group. The incidences of nausea, vomiting, apnea, desaturation, reintubation within 24 h and constipation were also similar between the two groups. We conclude that a remifentanil infusion provides clinically comparable analgesia with a fentanyl infusion in mechanically ventilated postoperative pediatric patients. These two drugs are suitable for short-term analgesia-based sedation in pediatric postoperative ICU patients.

Impact of gender on treatment and outcome of ICU patients

Gender modifies immunologic responses caused by severe trauma or critical illness. The aim of this study was to investigate the impact of gender on hospital mortality, length of intensive care unit (ICU) stay, and intensity of care of patients treated in ICUs. Data on 24,341 ICU patients were collected from a national database. We measured severity of illness with Acute Physiology and Chronic Health Evaluation II (APACHE II) scores and intensity of care with Therapeutic Intervention Scoring System (TISS) scores. We used logistic regression analysis to test the independent effect of gender on hospital mortality. We compared the lengths of ICU stay and the intensity of care of men and women. Male gender was associated with increased hospital mortality among postoperative ICU patients [adjusted odds ratio 1.33 (95% confidence interval 1.12-1.58, P = 0.001)] but not among medical patients [adjusted odds ratio 1.02 (95% confidence interval 0.92-1.13, P = 0.74)]. Male gender was associated with an increased risk of death particularly in the oldest age group (75 years or older) and among the patients with relatively low APACHE II scores (<16). Mean length of ICU stay was 3.2 days for men and 2.6 days for women (P < 0.001). Male patients comprised 61.7% of the study population but consumed 66.0% of days in intensive care. Male gender contributes to poor outcome in postoperative ICU patients. Approximately two-thirds of ICU resources are consumed by male patients.

Early postoperative substitution procedure of the antioxidant ascorbic acid

Background Postoperatively reduced concentration of ascorbic acid (AA) in plasma (≤45.5 μmol/l (≤800 μg/dl)) is commonly interpreted as increased metabolic requirements, but it is not shown yet that the patient benefits from a substitution toward normal levels of AA. This is due to the missing knowledge on how to substitute AA effectively to normal plasma values in postoperative patients. Therefore, a postoperative AA substitution procedure “overnight” to normal values in plasma was investigated on a postoperative intensive care unit (ICU) in a university hospital. Material and Methods Fifty-seven operated patients were randomly assigned to a control- or intervention group (CG and IG, respectively). In all patients, the AA plasma concentration was analysed preoperatively and on the first three postoperative days. Patients of the IG received AA intravenously up to four times within 12 h depending upon the initial AA concentration (<34.1 μmol/l (4×500 mg AA); ≤56.8 μmol/l (2×500 mg AA); ≤68.2 μmol/l (1×500 mg AA)). Results The preoperative and early postoperative AA values did not differ between the groups. On the first postoperative day in both groups the plasma concentration was lowered (≤45.5 μmol/l) in 23 of all patients (CG: 85.18%; IG: 82.14%). In the IG, the dosage regime increased the AA plasma concentration to ≥45.5 μmol/l in 26 of 28 (92.86%) patients overnight. Conclusion The investigated substitution procedure is sufficient to increase AA plasma concentration overnight to normal or high normal values in postoperative ICU patients.

Early postoperative substitution procedure of the antioxidant ascorbic acid (AA) in postoperative intensive care unit (ICU) patients

A postoperatively reduced concentration of AA in plasma (<45.5 μmol/l) is common due to increased metabolic requirements. Positive effects of AA in the postoperative period are well known (e.g. radical scavenger activity); hence there is an indication for the substitution of AA. However, the dosage commonly recommended for substitution during clinical nutrition is not adequate. Therefore, a postoperative AA substitution procedure 'overnight' to normal values in plasma was investigated in this randomized, prospective study on a postoperative ICU in a university hospital. Fifty-seven electively operated patients were assigned to a control group or an intervention group. In all patients the AA plasma concentration was analysed preoperatively and on the first three postoperative days. Patients of the intervention group received AA intravenously 'overnight' up to four times within 12 hours depending upon the initial AA concentration (< 34.1 μmol/l [4 × 500 mg AA]; < 56.8 μmol/l [2 × 500 mg AA]; < 68.2 μmol/l [1 × 500 mg AA]). The preoperative and postoperative AA values on the first postoperative day did not differ between both groups. However, the postoperative plasma concentration was lowered (< 45.5 μmol/l) in 82.4% of all patients. In the intervention group, the dosage regime increased the AA plasma concentration to > 45.5 μmol/l in 89.6% overnight. In conclusion, the investigated substitution procedure is sufficient to increase the AA plasma concentration overnight to high normal values in postoperative ICU patients.

Prevention of venous thromboembolism in critically ill surgery patients: A cross-sectional study

Background: The risk for venous thromboembolism (VTE) and the risk for bleeding among critically ill surgical patients are both important in the early postoperative period. Materials and Methods: To record VTE prophylaxis prescribed for surgical patients in the intensive care unit (ICU) within the first postoperative week. We conducted a prospective observational cross-sectional study of Canadian university affiliated ICUs. Results: Of 29 ICU Directors approached, 28 (96.6%) participated, representing 34 ICUs and 589 ICU beds across Canada. Among 89 patients, surgical procedures were 32 abdominal (36.0%), 19 vascular (21.3%), 10 orthopedic (11.2%), 9 trauma (10.1%), 8 neurologic (9.0%), 5 thoracic (5.6%), 5 gynecologic (5.6%), and 1 for necrotizing fasciitis (1.1%). VTE prophylaxis with unfractionated heparin, low molecular weight heparin, and intermittent pneumatic compression was used in 35 of 89 (39.3%), 8 of 89 (9.0%), and 9 of 89 (10.1%) patients, respectively, whereas 8 of 89 (9.0%) patients were receiving therapeutic anticoagulation. Two methods of VTE prophylaxis were prescribed for 20 of 89 (22.5%) patients. Prophylaxis with unfractionated or low molecular weight heparin was significantly less likely to be prescribed for postoperative ICU patients requiring mechanical ventilation compared with those weaned from mechanical ventilation (odds ratio [OR] 0.36, P = .03). The use of intermittent pneumatic compression devices was significantly associated with current hemorrhage (OR 13.5, P = .02), and risk for future hemorrhage (OR 19.3, P = .001). Conclusions: VTE prevention for surgical ICU patients within the first postoperative week appear to be individualized, and influenced by current and future risks of thrombosis and bleeding. Copyright © 2002 by W.B. Saunders Company

Semi-continuous versus injectate cardiac output measurement in intensive care patients after cardiac surgery.

Commercially available semi-continuous cardiac output (SCCO) monitoring systems are based on the pulsed warm thermodilution technique. There is evidence that SCCO fails to correlate with standard intermittent bolus cardiac output (ICO) in clinical situations with thermal instability in the pulmonary artery. Furthermore, ventilation may potentially influence thermodilution measurements by enhanced respiratory variations in pulmonary artery blood temperature and by cyclic changes in venous return. Therefore, we evaluated the correlation, accuracy and precision of SCCO versus ICO measurements before and after extubation. Prospective cohort study. Intensive care unit (ICU) of a university hospital. 22 cardiac surgical ICU patients. None. SCCO and ICO data were obtained at nine postoperative time points while the patients were on controlled mechanical ventilation. Further sets of measurements were taken during the weaning phase 20 min before extubation, and 5 min, 20 min and 1 h after extubation. SCCO and ICO measurements yielded 286 data pairs with a range of 1.8-9.9 l/min for SCCO and 1.9-9.8 l/min for ICO. The correlation between SCCO and ICO was highly significant (r = 0.92; p < 0.01), accompanied by a bias of -0.052 l/min and a precision of 0.56 l/min. Correlation, accuracy and precision were not influenced by the mode of respiration. Our results demonstrate excellent correlation, accuracy and precision between SCCO and ICO measurements in postoperative cardiac surgical ICU patients. We conclude that SCCO monitoring offers a reliable clinical method of cardiac output monitoring in ICU patients following cardiac surgery.