Piotr Knapik

Relationship between blood, nasopharyngeal and urinary bladder temperature during intravascular cooling for therapeutic hypothermia after cardiac arrest

OBJECTIVES Therapeutic hypothermia improves survival and neurological outcome in patients successfully resuscitated after cardiac arrest. Accurate temperature control during cooling is essential to prevent cooling-related side effects. METHODS Prospective observational study of 12 patients assessed during therapeutic hypothermia (32-34°C) achieved by intravascular cooling following cardiac arrest. Simultaneous temperature measurements were taken using a Swan-Ganz catheter (blood temperature BLT), nasopharyngeal probe (nasopharyngeal temperature NPT) and the urinary bladder catheter (urinary bladder temperature UBT). A total of 1728 measurements (144 measurements per patient) were recorded over a 48-h period and analyzed. Blood temperature was considered as the reference measurement. RESULTS Temperature profiles obtained from BLT, NPT and UBT compared with the use of analysis of variance did not differ significantly. Pearson correlation revealed that the correlation between BLT and NPT as well as BLT and UBT was statistically significant (r=0.96, p<0.001 and r=0.95, p<0.001, respectively). Bland-Altman analysis proved that the agreement between all measurements was satisfactory and the differences were not clinically important. CONCLUSIONS In 12 post-cardiac arrest patients undergoing intravascular cooling, both nasopharyngeal and urinary bladder temperature measurements were similar to blood temperatures measured using a pulmonary artery catheter.

The influence of heparin resistance on postoperative complications in patients undergoing coronary surgery

Summary Background Heparin resistance is relatively frequent in patients undergoing coronary surgery. We aimed to assess the impact of heparin resistance on the outcome of patients undergoing coronary surgery with cardiopulmonary bypass (CABG). Three definitions of heparin resistance were adopted. Material/Methods We performed a retrospective review of 756 consecutive patients undergoing isolated CABG. All anaesthesia records were reviewed manually. Heparin resistance was recognized if: ACT was less than 400 seconds after 300 U/kg heparin (local criteria), ACT was less than 480 seconds after 400 U/kg or more heparin (stringent criteria), or if heparin sensitivity index was lower than 1.3. Postoperative assessment included perioperative morbidity and mortality. A multiple logistic regression model was used to investigate the influence of all demographic, preoperative and surgical variables, as well as heparin resistance (variably defined) on hospital mortality and postoperative complications. Results Heparin sensitivity index, local criteria and stringent criteria identified 64.8%, 12.0% and 4.3% heparin resistant patients, respectively. Heparin-resistant patients more frequently had preoperative heparin administration, unstable course of coronary artery disease, and higher coronary symptoms scoring. Severe form of heparin resistance (expressed by the ACT less than 480 seconds after 400 U/kg heparin) was an independent predictor of death (OR 4.92; CI 1.11–21.89). Conclusions Mild forms of heparin resistance are relatively frequent and are not associated with increased morbidity and mortality. The isolation of severe heparin resistance as an independent predictor of death in our large cohort of coronary patients suggests that this phenomenon should be given more attention in future studies.

Utility of serum concentration of protein S100 at admission to the medical intensive care unit in prediction of permanent neurological injury

Introduction Admission to the intensive care unit (ICU) may be preceded by dramatic events leading to permanent neurological injury. Plasma S100 protein levels are proved to be clinically useful in predicting neurological outcome following cardiac arrest. It is unclear, however, whether this may be extrapolated to a broader population of ICU patients. Aim To assess the utility of plasma S100 protein in predicting death, permanent neurological damage, or unfavourable outcome at admission to the intensive care unit. Material and methods The concentration of plasma S100 protein was established in 102 patients on admission to the ICU, regardless of their neurological status and the reason for admission. The majority of patients were admitted with various cardiac diseases, excluding trauma patients. The patients were classified into three groups with the following binary outcomes: permanent neurological deficit or restoration of consciousness; unfavourable outcome (death or survival with permanent neurological deficit) or favourable outcome; and death or survival. Results Plasma S100 protein levels at admission facilitated the identification of patients who later developed a permanent neurological deficit or regained consciousness (p < 0.0001). All patients with plasma S100 protein over 0.532 μg/l at ICU admission either developed a permanent neurological deficit or had an unfavourable outcome (death or survival with permanent neurological deficit). However, sensitivity for this cut-off value was only 48% and 40%, respectively. Conclusions Plasma S100 protein levels over 0.532 μg/l are specific but not sensitive for both permanent neurological deficit and unfavourable outcome when assessed in a heterogeneous population at admission to the ICU.

Surgical treatment of left main disease and severe carotid stenosis: does the off-pump technique provide a better outcome?

OBJECTIVES Left main disease (LMD), combined with carotid artery stenosis (CAS), constitutes a high-risk patient population. Priority is often given to coronary revascularization, due to the severity of the angina. However, the choice of revascularization strategy [off-pump coronary artery bypass (OPCAB) vs coronary artery bypass grafting (CABG)] remains elusive. METHODS A total of 1340 patients with LMD were non-randomly assigned to either on-pump (CABG group, n = 680) or off-pump (OPCAB group, n = 634) revascularization between 1 January 2006 and 21 September 2010. Multivariable regression was used to determine the risk-adjusted impact of a revascularization strategy on a composite in-hospital outcome (MACCE), and proportional hazards regression was used to define the variables affecting long-term survival. RESULTS Significant CAS was found in 130 patients: 84 (13.1%) patients underwent OPCAB, while 46 patients (6.8%) underwent CABG (P < 0.05). Patients with a history of stroke/transient ischaemic attack were also more likely to receive OPCAB (7.1 vs 4.7%; P = 0.08). OPCAB patients were older, in a higher New York Heart Association (NYHA) class, with a lower LVEF and higher EuroSCORE. A calcified aorta was found in 79 patients [OPCAB-CABG: 49 (7.73%) vs 30 (4.41%); P = 0.016] and resulted in a less complex revascularization (OPCAB-CABG: 2.3 ± 0.71 vs 3.19 ± 0.82; P < 0.05), and 30-day mortality was insignificantly higher in the CABG (2.7 vs 2.8%) as well as MACCE (11.2 vs 12.2%; P = NS). This trend reversed when late mortality was evaluated; however, it did not reach significance at 60 months. Preoperative renal impairment requiring dialysis was found to be a technique-independent predictor of MACCE. The number of arterial conduits also influenced MACCE. CONCLUSIONS Off-pump coronary revascularization may offer risk reduction of neurological complications in patients with a significant carotid artery disease and a history of previous stroke, but a larger study population is needed to support this thesis. The growing discrepancy in long-term survival should draw attention to a more complete revascularization in OPCAB patients.

Ropivacaine has no advantage over bupivacaine in thoracic epidural analgesia for patients with pectus excavatum undergoing the Nuss procedure – a single blind randomized clinical trial comparing efficacy and safety

Introduction Pectus excavatum repair (Nuss procedure) is a painful procedure requiring effective postoperative analgesia. Aim To establish whether thoracic epidural analgesia with ropivacaine is non-inferior to epidural analgesia with bupivacaine following the Nuss procedure in children. Material and methods The prospective, randomized, controlled, single blind study included 81 children. Computer-generated random numbers were used to allocate treatment. All children received general anesthesia. Intraoperative and postoperative analgesia was achieved with either 0.5% and 0.1% ropivacaine (group R) or 0.375% and 0.0625% bupivacaine (group B). The Numeric Rating Scale (NRS) and the Prince Henry Hospital Pain Score (PHHPS) were used to assess postoperative pain directly after and 1, 8, 20 and 24 hours after awakening from general anesthesia. NRS scores of more than 2 and a PHHPS score of more than 1 were considered as pain requiring intervention. Hemodynamic stability and side effects were also compared between the groups. Results The durations of the procedure and extubation times in groups R and B were similar (59 ±7 vs. 56 ±10 minutes and 9 ±5 vs. 10 ±5 minutes, respectively). Pain scores requiring intervention were below 10% and were recorded with similar frequency in both groups, except for one difference in the PHHPS score in favor of group R after 24 hours (12% vs. 40%, p < 0.05). The frequency of side effects and hemodynamic stability were similar in both groups. Conclusions 0.1% epidural ropivacaine has no advantage over 0.0625% epidural bupivacaine for pectus excavatum repair in children.

Evaluation of thoracic epidural analgesia in patients undergoing coronary artery bypass surgery – a prospective randomized trial

Introduction Most recent studies tend to confirm the beneficial effect of thoracic epidural analgesia (TEA) in cardiac surgery. Aim To assess whether intensive care unit TEA has an influence on the perioperative course following low-risk coronary artery surgery. Material and methods This prospective, randomized trial was performed in patients scheduled for low-risk coronary artery surgery. Eighty patients undergoing off-pump or on-pump coronary artery bypass surgery were prospectively randomized to receive either combined general and epidural anesthesia or general anesthesia only. Time of postoperative ventilations and intensive care unit stay was compared between the groups. For all comparisons (p < 0.05) was considered statistically significant. Results The addition of TEA to general anesthesia significantly attenuated the stress response expressed by intraoperative heart rate, systolic blood pressure and cumulative doses of opioids. Time to the return of spontaneous respiration, time to extubation and time of stay in the postoperative care unit were all shorter in the study group, with no difference in hospital stay. Patients with TEA required midazolam less frequently (12.8% vs. 53.8%, p < 0.001). The percentage of patients given morphine in the study group was lower (46.2% vs. 89.7%, p < 0.001) and the mean dose given in patients receiving morphine was also lower (9.3 ±5.3 mg vs. 18.2 ±9.1 mg, p < 0.001). Conclusions Addition of TEA to general anesthesia shortens the return of respiratory function, duration of mechanical ventilation and ICU stay in the postoperative period after coronary artery surgery, providing comparable hemodynamic stability to general anesthesia alone.

Day and time of admissions to intensive care units — does it matter?

BACKGROUND The literature data pertaining to the significance of day and time of ICU admission for outcomes of patients are inconsistent. The issue has not been analysed in Poland to date. The aim of the study was to gather information about differences between patients admitted to ICU outside regular working hours (off-hours) and those admitted during working hours (on-hours). METHODS Analysis involved 20,651 patients from the Silesian Registry of Intensive Care Units carried out since 2010. The findings demonstrated that 34.8% of patients were admitted to ICUs during on-hours (between 8.00 a.m. and 3 p.m. on weekdays) and 65.2% were admitted during off-hours (outside regular working hours). The incidence of admissions and data of patients in both groups were compared in terms of the population characteristics and treatment outcomes. RESULTS The incidence of admissions (calculated per each 24 hours of treatment) was found to be almost twice as high during on-hours, as compared to off-hours (14.5 vs. 6.9 patients/day). Patients admitted to the ICU during on-hours were less likely to be admitted from the surgical department (19.1% vs. 31.0%, P < 0.001), and more likely to be admitted from the emergency department (25.3% vs. 14.2%, P < 0.001). The incidence of off-hours admissions of cancer patients was lower (5.3% vs. 10.8%, P < 0.001), as compared with patients with alcohol dependence syndrome (10.3% vs. 6.9%, P < 0.001). Patients admitted during off-hours were in more severe conditions and had higher APACHE II scores (on average, 23.8 ± 8.8 vs. 21.8 ± 8.8, P < 0.001); their mortality rates were higher compared to the remaining population (46.8% vs. 39.4%, P < 0.001). CONCLUSIONS Patients admitted to ICUs during off-hours are in more severe general condition and their treatment outcomes are worse, as compared to patients admitted to ICU during on-hours.

Mortality of patients with acute kidney injury requiring renal replacement therapy

BACKGROUND Acute kidney injury (AKI) in critically ill patients has a deleterious impact on the prognosis, especially when renal replacement therapy (RRT) is required. This issue has not yet been investigated in the intensive care setting in Poland. OBJECTIVES The aim of the study was to evaluate the short-term outcomes of AKI-RRT subjects, based on a large registry population. MATERIAL AND METHODS This observational multicenter study covered 100 demographic and clinical variables from the Silesian Registry of ICUs regarding 15,030 adult patients hospitalized between October 2011 and December 2014. The study group comprised 1,234 AKI individuals (8.2%) who required RRT. The primary outcome was ICU mortality. The length of ICU stay (LOS) was considered the secondary outcome. Observed mortality was compared to that predicted by the Acute Physiology and Chronic Health Evaluation II (APACHE II). RESULTS The overall mortality of the patients in the registry was 43.9%; it was higher in AKI-RRT subjects than in non-AKI-RRT counterparts (69.4% vs 41.0%; p < 0.01). The median APACHE II score among AKI-RRT subjects was 26 (IQR: 20-32) points. The observed mortality among AKI-RRT patients was significantly higher than predicted by APACHE II, particularly in individuals with lower baseline risk (overall difference: 14.4%). Six patient-related variables independently predicted ICU mortality with moderate accuracy (area under the receiver operating characteristic, AUROC = 0.675; 95% CI 0.65-0.70). The ICU LOS of AKI-RRT subjects was longer than that of the controls (9.8 [IQR: 4.0-19] vs 5.7 [IQR: 2.1-12] days; p < 0.001). CONCLUSIONS The mortality of critically ill AKI patients requiring RRT was significantly higher than in the overall ICU population. APACHE II scores underestimate mortality, especially in low-risk AKI-RRT subjects, and therefore should not be used in prognostic models in this cohort.

Perioperative care in elderly cardiac surgery patients

Introduction Surgery is an extreme physiological stress for the elderly. Aging is inevitably associated with irreversible and progressive cellular degeneration. Patients above 75 years of age are characterized by impaired responses to operative stress and a very narrow safety margin. Aim To evaluate perioperative complications in patients aged ≥ 75 years who underwent cardiac surgery in comparison to outcomes in younger patients. Material and methods The study was conducted at the Silesian Centre for Heart Diseases in Zabrze in 2009–2014 after a standard of perioperative care in seniors was implemented to reduce complications, in particular to decrease the duration of mechanical ventilation and reduce postoperative delirium. The study group included 1446 patients. Results The mean duration of mechanical ventilation was 13.8 h in patients aged ≥ 75 years and did not differ significantly compared to younger patients. In-hospital mortality among seniors was 3.8%, a value significantly higher than that observed among patients younger than 75 years of age. Patients aged ≥ 75 years undergoing cardiac surgery have significantly more concomitant conditions involving other organs, which affects treatment outcomes (duration of hospital stay, mortality). Conclusions The implementation of a standard of perioperative care in this age group reduced the duration of mechanical ventilation and lowered the rate of postoperative delirium.

Outcomes of patients with acute kidney injury with regard to time of initiation and modality of renal replacement therapy – first data from the Silesian Registry of Intensive Care Units

Introduction Acute kidney injury (AKI) remains a serious clinical problem in the intensive care unit (ICU). It constitutes an independent risk factor for mortality, especially when renal replacement therapy (RRT) is required. Aim Due to limited evidence pertaining to timing, choice of RRT modality and lack of studies investigating AKI in Polish ICUs, we sought to analyse outcomes of adult AKI-RRT ICU patients in the Silesian Voivodeship. Material and methods We analysed data regarding 1,380 patients with AKI who required RRT (AKI-RRT) (9.2% of all subjects in the registry) hospitalized between October 2011 and December 2014 in Silesian ICUs. The primary outcome was crude ICU mortality. Length of ICU stay (LOS) was considered the secondary outcome. Results Of 15,030 patients 1,380 (9.2%) individuals developed AKI requiring RRT. The overall mortality in the registry was 43.9%, but it was significantly higher (69.1%) in AKI-RRT patients (p < 0.01). Mortality with regard to timing of institution of RRT was 67.1% in the group with RRT instituted prior to ICU admission (RRT-prior-ICU) and 69.4% in patients with RRT instituted during ICU hospitalization (RRT-in-ICU) (p = 0.58). Conclusions Multiple patient- and hospitalization-related factors determine mortality in this specific cohort. There are no differences in mortality with regard to RRT being initiated before or during hospitalization in the ICU. Due to multiple confounders, differences in mortality in terms of modality of RRT should be interpreted with caution.