Heart Rate Ratio Research Articles

Prognostic Value of Shock Index in Children With Septic Shock

Septic shock is frequent in children and is associated with high mortality and morbidity rates. Early recognition of severe sepsis improve outcome. Shock index (SI), ratio of heart rate (HR) and systolic blood pressure (SBP), may be a good noninvasive measure of hemodynamic instability that has been poorly studied in children. The aim of the study was to explore the usefulness of SI as an early index of prognosis for septic shock in children. The study was retrospective and performed in 1 pediatric intensive care unit at a university hospital. The following specific data were collected at 0, 1, 2, 4, and 6 hours after admission: HR and SBP for SI calculation and lactate concentration. Patients were divided into 2 groups according to their outcome (death/survival). A total of 146 children admitted with septic shock between January 2000 and April 2010 were included. Shock index was significantly different between survivors and nonsurvivors at 0, 4, and 6 hours after admission (P = 0.02, P = 0.03, and P = 0.008, respectively). Age-adjusted SIs were different between survivors and nonsurvivors at 0 and 6 hours, with a relative risk of death at these time points of 1.85 (1.04-3.26) (P = 0.03) and 2.17 (1.18-3.96) (P = 0.01), respectively. Moreover, an abnormal SI both at admission and at 6 hours was predictive of death with relative risk of 1.36 (1.05-1.76). In our population of children with septic shock, SI was a clinically relevant and easily calculated predictor of mortality. It could be a better measure of hemodynamic status than HR and SBP alone, allowing for the early recognition of severe sepsis.

Effects of Music Tempo on Performance, Psychological, and Physiological Variables during 20 Km Cycling in Well-Trained Cyclists

Few studies have investigated the effects of music on trained athletes during high intensity endurance tasks. Therefore, this study investigated the effects of different music tempi on performance, psychological, and physiological responses of well-trained cyclists to time trial cycling. 10 male road cyclists (M age = 35 yr., SD = 7), with a minimum of three years racing experience, performed four 20-km time trials on a Computrainer Pro 3D indoor cycle trainer over a period of four weeks. The time-trials were spaced one week apart. The music conditions for each trial were randomised between fast-tempo (140 bpm), medium-tempo (120 bpm), slow-tempo (100 bpm), and no music. Performance (completion time, power output, average speed and cadence), physiological (heart rate, oxygen consumption, breathing frequency and respiratory exchange ratio), psychophysical (RPE), and psychological (mood states) data were collected for each trial. Results indicated no significant changes in performance, physiological, or psychophysical variables. Total mood disturbance and tension increased significantly in the fast-tempo trial when compared with medium and no-music conditions.

Is Shock Index Associated With Outcome in Children With Sepsis/Septic Shock?*

To investigate the association between PICU shock index (the ratio of heart rate to systolic blood pressure) and PICU mortality in children with sepsis/septic shock. To explore cutoff values for shock index for ICU mortality, how change in shock index over the first 6 hours of ICU admission is associated with outcome, and how the use of vasoactive therapy may affect shock index and its association with outcome. Retrospective cohort. Single-center tertiary PICU. Five hundred forty-four children with the diagnosis of sepsis/septic shock. None. From January 2003 to December 2009, 544 children met International Pediatric Sepsis Consensus Conference of 2005 criteria for sepsis/septic shock. Overall mortality was 23.7%. Among all patients, hourly shock index was associated with mortality: odds ratio of ICU mortality at 0 hour, 1.08, 95% CI (1.04-1.12); odds ratio at 1 hour, 1.09 (1.04-1.13); odds ratio at 2 hours, 1.09 (1.05-1.13); and odds ratio at 6 hours, 1.11 (1.06-1.15). When stratified by age, early shock index was associated with mortality only in children 1-3 and more than or equal to 12 years old. Area under the receiver operating characteristic curve in age 1-3 and more than or equal to 12 years old for shock index at admission was 0.69 (95% CI, 0.58-0.80) and 0.62 (95% CI, 0.52-0.72) respectively, indicating a fair predictive marker. Although higher shock index was associated with increased risk of mortality, there was no particular cutoff value with adequate positive or negative likelihood ratios to identify mortality in any age group of children. The improvement of shock index in the first 6 hours of ICU admission was not associated with outcome when analyzed in all patients. However, among patients whose shock index were above the 50th percentile at ICU admission for each age group, improvement of shock index was associated with lower ICU mortality in children between 1-3 and more than or equal to 12 years old (p = 0.02 and p = 0.03, respectively). When controlling for the use of vasoactive therapy within the first 6 hours with logistic regression analysis, shock index at hour 6 remained significantly associated with mortality (odds ratio, 1.09; 95% CI, 1.05-1.14). Shock index may have promise as a marker of mortality in children with sepsis/septic shock. Although there is no clear cutoff shock index to identify risk of mortality, given the higher risk of mortality as shock index increases, children with elevated shock index may benefit from more aggressive resuscitation and higher level of care.

A Sensitive Shock Index for Real-Time Patient Assessment During Simulated Hemorrhage

Shock index [SI = the ratio of heart rate (HR) to systolic arterial pressure (SAP)] is a metric used to diagnose patients at risk of impending hemorrhagic shock. We hypothesized that a metric called the compensatory reserve index (CRI), derived using computer modeling with continuous feature extraction from arterial waveforms, would provide an earlier indicator of cardiovascular instability than SI during progressive central hypovolemia. There were 15 subjects (men = 8; women = 7) who underwent progressive reduction in central blood volume induced by lower body negative pressure (LBNP) until SAP < 90 mmHg. CRI was normalized on a scale of 1 (normovolemia) to 0 (circulatory volume at which instability occurs) and displayed on a colored bar. The times at which the CRI equaled 0.6 (threshold of green to amber) or 0.3 (threshold of amber to red) were compared to a clinical threshold of SI > or = 0.9. A SI > or = 0.9 required 22.4 +/- 6.2 min (95% CI = 19 to 25.8 min). CRI reached 0.6 (amber) at 12.5 +/- 4.9 min (95% CI = 9.8 to 15.3 min) when SI = 0.61 +/- 0.03, and became 0.3 (red) at 20.3 +/- 5.1 min (95% CI = 17.5 to 23.1 min) when SI = 0.81 +/- 1.4. CRI provided a significantly earlier indicator of impending hemodynamic decompensation than SI > or = 0.9 during progressive LBNP. These results support the notion that the CRI represents an improved 'shock index' as an indicator of impending hemorrhagic shock compared to standard vital signs.

High prevalence of false-positive plateau phenomena during VO2max testing in adolescents

It is believed that a plateau in oxygen consumption (VO2) at the end of an incremental exercise test identifies the upper limits of cardiovascular capacity. We investigated how different criteria influence the frequency with which the "plateau phenomenon" is detected and the prevalence at which "false" plateau phenomena occurs during sub-maximal exercise. Cross-sectional. Six different criteria with 3 different sampling intervals each were used to identify the "plateau phenomenon" from a single data set comprising 63 incremental exercise tests along with secondary criteria based on target heart rate (HR) and respiratory exchange ratio (RER). A single criterion from the original 18 (HALF) was also used to detect the incidence of any plateau phenomena during each test. The plateau phenomenon was detected in 16-82% of the tests depending on the criteria used, mostly as a result of the different sampling intervals. HALF identified 103 "plateau phenomena" but 73 (70.9%) of these occurred during sub-maximal exercise and so were "false". "False" plateaus were verified by at least one secondary criterion in 27% of cases. Participants reached the HR and RER targets after 83.6 ± 11.7% and 81.9 ± 18.1% of total test duration, respectively. The wide range in the percentage of plateau phenomena detected by different criteria plus the high rate (71%) of "false" plateau during sub-maximal exercise could indicate that this phenomenon is a calculation artifact rather than an indicator of true physiological events. Secondary criteria can be reached early in exercise and often identify "false" plateau phenomena as "true".

Physiologic mechanisms underlying the failure of the “shock index” as a tool for accurate assessment of patient status during progressive simulated hemorrhage

Shock index (SI), the ratio of heart rate (HR) to systolic arterial pressure (SAP), is a metric often used to diagnose patients at risk of impending cardiovascular instability and hemorrhagic shock. We hypothesized that if SI reflected impending cardiovascular instability and shock in an individual, then: (1) elevations in SI and HR would be greater in individuals with low tolerance (LT) to progressive lower-body negative-pressure (LBNP) compared with individuals with high tolerance (HT), and (2) LT would be associated with greater vagal withdrawal of the baroreflex sensitivity (BRS) compared with HT. A total of 187 healthy subjects (HT, 125; LT, 62) underwent exposure to LBNP until a SAP of less than 80 mm Hg (instability) was achieved. HR and SAP were used to calculate SI, and BRS was determined from spontaneous fluctuations in R-R interval and diastolic arterial pressure. Maximal cardiac vagal withdrawal was calculated as the difference between BRS at baseline and BRS at 100% LBNP tolerance. Contrary to our hypothesis, SI at 60%, 80%, and 100% LBNP tolerance in LT (0.59 ± 0.03, 0.73 ± 0.04, and 0.97 ± 0.06, respectively) was lower (p ≤ 0.002) than SI in HT subjects at the same levels (0.66 ± 0.03, 0.84 ± 0.04, and 1.24 ± 0.06, respectively). Maximal cardiac vagal withdrawal was less (p = 0.045) in LT subjects (11.3 ± 2.2 ms/mm Hg) compared with HT subjects (14.9 ± 2.5 ms/mm Hg). The sensitivity of SI in identifying impending instability (SI, 0.9) at 80% and 100% LBNP tolerance was 13% and 63% in LT subjects and 34% and 91% in HT subjects, respectively. The low sensitivity of the SI observed in LT individuals is associated with a lower capacity to withdraw cardiac vagal activity and can lead to an undertriage of those patients most likely to develop early hemorrhagic shock.

Test–Retest Reliability of Portable Metabolic Monitoring After Disabling Stroke

Purpose. Impaired economy of gait, prevalent in chronic stroke secondary to residual gait deficits, is associated with intolerance for performing activities of daily living. Gait economy/efficiency is traditionally assessed by determining the rate of oxygen consumption during submaximal treadmill walking. However, the mechanics and energetics of treadmill versus overground walking are very different in stroke survivors with ambulatory deficits. Clearly, overground cardiopulmonary measures are needed to accurately profile movement economy after stroke. An obstacle to obtaining such measures after stroke has been the absence of reliable portable metabolic monitoring equipment. The purpose of this study was to establish the test–retest reliability of a portable metabolic monitoring device during overground walking in hemiparetic stroke survivors. Methods. Twenty-three chronic hemiparetic stroke survivors underwent two 6-minute walk tests while wearing a COSMED K4b2 portable metabolic measurement system. Intraclass correlations coefficients (ICC) were calculated for both cardiopulmonary parameters and distance covered to determine test–retest reliability. An ICC of ≥0.85 was considered reliable. Results. ICCs for relative Vo2 (0.90), absolute Vo2 (0.93), Vco2 (0.93), and minute ventilation (0.95) demonstrated high reliability, but not for heart rate (0.76) or respiratory exchange ratio (0.64). There was no significant difference in the distance each participant walked between the first and second tests, eliminating distance as a potential confounder of our analyses (ICC = 0.99). Conclusions. Our results strongly support the reliability of the K4b2 for quantifying overground gait efficiency after stroke. Use of this device may enable researchers to study how varying poststroke rehabilitation interventions affect this central measure of health and function.

An analysis of shock index as a correlate for outcomes in trauma by age group

Shock index as the ratio of heart rate to systolic blood pressure is a simple triage tool that correlates well with various outcomes in trauma patients. Concern has been raised regarding the accuracy of shock index in older patients. We sought to investigate the effects of age on the accuracy of shock index. This is a retrospective review of data from a level I trauma center. Shock index was calculated for 16,269 patients, and they were stratified into age groups by decade. The correlation between prehospital shock index for each of the age groups and for several outcome variables were evaluated by Pearson correlation coefficients. Logistic regression was used to evaluate an increase in shock index during transit and its relationship with mortality. All correlation values for patients between 16 and 60 years of age were positive (P < .05). In patients who are older than 80 years, none of the correlations with the outcome variables were statistically significant. In patients older than 60 years, an increased shock index during transit correlated with an increase in mortality rates. As expected, prehospital shock index alone has diminishing accuracy for patients older than 60 years of age and should be interpreted cautiously by trauma triage personnel. Shock index alone in patients younger than 60, and its increase during transit in patients older than 60, can be used as a valuable tool for the prehospital triage of trauma patients when determining the need for transport to a trauma center, preparation of resources, or activation of the trauma team.

Response of the airways and autonomic nervous system to acid perfusion of the esophagus in patients with asthma: a laboratory study

BackgroundGastro-esophageal reflux disease (GERD) predisposes to airway disease through a vagally-mediated esophago-bronchial reflex. This study investigates this vagal response to esophageal acid perfusion.Methods40 asthmatics with mild stable asthma participated. Each subject underwent spirometry and autonomic function testing (valsalva maneuver, heart rate response to deep breathing and to standing from supine position) four times: a) before intubation, b) after intubation, and then immediately after perfusion with, in random order, c) concentrated lime juice solution (pH 2–3) and d) 0.9% saline. Subjects were blinded to the solution perfused.ResultsAsthmatics were of mean (SD) age 34.3 years (1.3), and 67.5% of them were females. pH monitoring demonstrated that 20 subjects had abnormal reflux and 20 did not. In each group 10 subjects had a positive GERD symptom score. Following perfusion with acid compared to saline, all subjects showed significant decreases in FEV1 and PEFR and significant increases in the mean valsalva ratio and heart rate difference on deep breathing from baseline values, but no changes in FVC or heart rate ratio on standing. There were no significant differences in any of the parameters between subjects with and without reflux.ConclusionsAcid stimulation of the distal esophagus results in increased parasympathetic activity and concomitant broncho-constriction in asthmatics irrespective of their reflux state. This strengthens the hypothesis that GER triggers asthma-like symptoms through a vagally mediated esophago-bronchial reflex and encourages a possible role for anti-cholinergic drugs in the treatment of reflux-associated asthma.

The pulse pressure/heart rate ratio as a marker of stroke volume changes during hemorrhagic shock and resuscitation in anesthetized swine

Emergency physicians and anesthesiologists need accurate estimates of stroke volume when massive unexpected hemorrhage occurs. Using an animal model of hemorrhagic shock under general anesthesia, we hypothesized that the pulse pressure-heart rate ratio (PP/HR) would be an accurate marker of stroke volume changes during hemorrhage and resuscitation. In 16 swine under bispectral index-controlled, intravenous propofol-remifentanil anesthesia, pressure-controlled hemorrhagic shock was induced to achieve 30 mm Hg of mean arterial pressure, after which treatment was randomized to fluid (HES, n = 4), norepinephrine (NE, n = 4), both (HES + NE, n = 4), or neither (control, n = 4). Pulmonary artery thermodilution continuous cardiac output, stroke volume, and central arterial pressures were recorded at baseline (T0), after 30 minutes (T30) and 60 (T60) minutes of hemorrhage, during treatment (T90 and T120) and after blood retransfusion (T180). At T60, blood withdrawal was 995 (301) mL (38 [8] mL/kg), resulting in a 70% decrease in stroke volume and a 3.3-fold decrease in PP/HR (each p < 0.01). When stroke volume data pointed at T0, T30 and T60 were plotted against the various hemodynamic variables under study, the PP/HR ratio exhibited the strongest relationship to stroke volume (r = 0.72). The area under the receiver operating characteristic curve set to detect a 15% stroke volume decrease was larger for PP/HR (0.95 [0.94-0.97]) than for mean arterial pressure (0.91 [0.89-0.93]) (p < 0.013). During resuscitation in the HES and NE groups, correlation coefficients were significantly higher between stroke volume and PP/HR (0.75 [0.63-0.84] and 0.79 [0.67-0.86]) than between stroke volume and mean arterial pressure (0.52 [0.32-0.67], p = 0.042, and 0.49 [0.28-0.65], p = 0.0018, respectively). The PP/HR ratio was strongly related to stroke volume during hemorrhagic shock and resuscitation in anesthetized swine.

ECG DISPERSION MAPPING PARAMETERS DURING THE TREADMILL TEST IN PATIENTS WITH CORONARY HEART DISEASE

Aim.The aim of the study was the complex analysis of the ECG-12 and ECG dispersion mapping (DM) parameters during the physical stress test in patients with coronary heart disease (CHD).Material and methods.The main group included 143 CHD patients with Functional Class I–III angina (99 men and 44 women; mean age 50,6±4,6 years). The control group included 37 healthy individuals (mean age 44,3±4,8 years). Patients with heart failure signs and symptoms were excluded. All participants underwent the graduated physical stress test.Results.Two variants of the ECG changes were observed, with normal and abnormal reaction of ECG DM parameters. The latter group was characterised by the following: ratio of heart rate and myocardial micro-alternation index (HRmax/MMImax) 30% at the peak HR.Conclusion.Using the ECG DM method during the treadmill test is a feasible and useful approach to gain additional diagnostic information on the myocardial electro-physiological status and, therefore, to select the patients who need further examination and treatment.

ECG DISPERSION MAPPING PARAMETERS DURING THE TREADMILL TEST IN PATIENTS WITH CORONARY HEART DISEASE

Aim. The aim of the study was the complex analysis of the ECG-12 and ECG dispersion mapping (DM) parameters during the physical stress test in patients with coronary heart disease (CHD).Material and methods. The main group included 143 CHD patients with Functional Class I–III angina (99 men and 44 women; mean age 50,6±4,6 years). The control group included 37 healthy individuals (mean age 44,3±4,8 years). Patients with heart failure signs and symptoms were excluded. All participants underwent the graduated physical stress test.Results. Two variants of the ECG changes were observed, with normal and abnormal reaction of ECG DM parameters. The latter group was characterised by the following: ratio of heart rate and myocardial micro-alternation index (HRmax/MMImax) 30% at the peak HR.Conclusion. Using the ECG DM method during the treadmill test is a feasible and useful approach to gain additional diagnostic information on the myocardial electro-physiological status and, therefore, to select the patients who need further examination and treatment.

Monitoring respiration in wheezy preschool children by pulse oximetry plethysmogram analysis

The aim of this study was to investigate whether respiratory information can be derived from pulse oximetry plethysmogram (pleth) recordings in acutely wheezy preschool children. A digital pulse oximeter was connected via 'Bluetooth' to a notebook computer in order to acquire pleth data. Low pass filtering and frequency analysis were used to derive respiratory rate from the pleth trace; the ratio of heart rate to respiratory rate (HR/RR) was also calculated. Recordings were obtained during acute wheezy episodes in 18 children of median age 31 months and follow-up recordings from 16 of the children were obtained when they were wheeze-free. For the acutely wheezy children, frequency analysis of the pleth waveform was within 10 breaths/min of clinical assessment in 25 of 29 recordings in 15 children. For the follow-up measurements, frequency analysis of the pleth waveform showed similarly good agreement in recordings on 15 of the 16 children. Respiratory rate was higher (p < 0.001), and HR/RR ratio was lower (p = 0.03) during acute wheeze than at follow-up. This study suggests that respiratory rate can be derived from pleth traces in wheezy preschool children.

Cardiovascular autonomic function in lateral medullary infarction

Even though the medulla contains the baroreceptor regulatory centers, few studies have focused on the autonomic dysfunction of lateral medullary infarction (LMI). Therefore, cardiac parasympathetic and sympathetic functions were compared in LMI patients and age-matched controls. We prospectively recruited 25 LMI patients who had ipsilateral Horner's sign and cardiac autonomic function testing without a history of diabetes, cardiac disease, or previous stroke. Parasympathetic function tests included beat-to-beat heart rate variation during deep breathing, 30:15 heart rate ratio testing while standing, and the valsalva ratio. Sympathetic function tests included blood pressure during active standing and sustained handgrip. The composite autonomic score (CAS) was measured as a total of 10 points; parasympathetic dysfunction was designated as ≥3 points in the parasympathetic subscores and sympathetic dysfunction as ≥2 points in the sympathetic subscores. Multiple regression analysis was performed to predict parasympathetic or sympathetic dysfunction. The mean age and stroke risk factors of the study population were not significantly different between the LMI group (n = 25) and control group (n = 29). However, cardiac autonomic functions were significantly different in the groups: parasympathetic dysfunction (14 vs. 4 patients, p = 0.011) and sympathetic dysfunction (3 vs. 13 patients, p = 0.008). In univariate analysis, male-gender (p = 0.011), right-side involvement (p = 0.035) and ventral involvement (p = 0.007) were significantly associated with parasympathetic dysfunction (CAS subscore ≥3). In multivariable analysis, the ventral involvement remained to be the independent predictor for parasympathetic dysfunction (OR 16.0; 95% CI 2.2-118.3, p = 0.007). This study suggests that LMI patients are susceptible to cardiac parasympathetic dysfunction, especially in the ventral medulla.

Age- and sex-specific normal values for shock index in National Health and Nutrition Examination Survey 1999-2008 for ages 8 years and older

PurposeShock index (SI), the ratio of heart rate to systolic blood pressure, has found to outperform conventional vital signs as a predictor of shock. Although age-specific vital sign norms are recommended in screening for shock, there are no reported age- or sex-specific norms for SI. Our primary goal was to report age- and sex-specific SI normal values for a nationally representative population 10 years and older by 5-year age groups. A secondary goal was to report SI normal values for children ages 8 to 19 years by 1-year age groups. Basic proceduresWeighted data from the National Health and Nutrition Examination Survey 1999-2008 data sets were used to generate age- and sex-specific percentile curves of SI for subjects 8 years and older. Main findingsThe primary analysis included 33906 subjects (101837 weighted) 10 years and older. The secondary analysis included 13393 subjects (37983 weighted) 8 to 19 years old. Normalized SI values for each percentile decreased with increasing age and were higher for females across all ages. The most commonly cited SI threshold of 0.9 exceeded the 97th percentile for males younger than 25 years and for females younger than 40 years. ConclusionsThis first report of age- and sex-specific normal values for SI indicates that SI norms vary by age and sex. Just as age-specific vital sign norms are recommended in screening for shock, our findings suggest that age- and sex-specific SI norms may be more effective in screening for shock than a single-value threshold.

Heart rate, ejection duration and subendocardial viability ratio in patients with rheumatoid arthritis as compared to controls

Rheumatoid arthritis (RA) is associated with increased cardiovascular morbidity and mortality. In the general population, an increased heart rate is associated with increased mortality. Only a few studies have investigated heart rate in RA patients and compared the results with patients that do not have RA (n-RA). Therefore, little is known as to whether an increased heart rate, at least in part, could explain the increased mortality found in RA patients. The aim of the present study was to investigate whether heart rate is increased in RA patients. In this cross-sectional study, heart rate was determined in a total of 282 patients (131 RA, 151 n-RA). In addition, non-invasive pulse wave analysis of the radial artery was performed to determine cardiac ejection duration using the Sphygmocor apparatus. Furthermore, the subendocardial viability ratio (SEVR), a marker of cardiac workload, was investigated, whereby higher values indicate a more favorable supply/demand relationship for the myocardium. Patients using chronotropic drugs were not included in the study. Heart rate was virtually the same in RA patients (71.9±11.2 beats/min [bpm]) as compared with controls (72.3±11.7bpm; P>0.05). Also SEVR (RA 144±25% vs. n-RA 147±27%; P>0.05) and ejection duration (RA 321±24ms vs. n-RA 318±24ms; P>0.05) were comparable between the groups. It could not be shown that heart rate in RA patients differs significantly from heart rate in controls. Therefore, heart rate does not appear to explain or contribute to the increased cardiovascular risk found in RA patients.

316: Diuretic is safe and superior to volume expansion in normotensive patients with acute pulmonary embolism and right ventricular dilatation

The rational and the benefit of load expansion is controversial in acute pulmonary embolism (PE). Diuretic may reduce RV preload and improve hemodynamic status. The present study reported the safety of furosemide in normotensive acute PE with oligo-anuria. We prospectively included 68 consecutive normotensive patients (systolic blood pressure ≥90 mmHg) admitted for acute PE with oligoanuria and RV dilation. RV dilation was defined by a right and left ventricular diameter ratio >0.6. Overall, 29 patients were treated by a repeated bolus of furosemide (83±84 mg, range 40 to 160 mg), while 39 patients received isotonic saline solution (1.6±0.8 L, range, 0.5 to 4,0 L). Patients treated by furosemide and fluid expansion had similar severity of hypoxemia but the furosemide group had lower admission blood pressure (119±21 mmHg vs. 132±18 mmHg, P=0.007) and greater shock index defined as heart rate and blood pressure ratio (0.81±0.23 vs. 0.69±0.18, P=0.02). Despite these differences, only the furosemide group had decrease shock index (0.81±0.23 vs. 0.62±0.17, P<0.0001) with improved systolic blood pressure (119±21 mmHg vs. 133 ±18 mmHg, P<0.001), heart rate (93±19 bpm vs. 81±18 bpm, P<0.001), and creatinin level. Finally, more patients were weaned in oxygen at 24 hours (39% vs. 19%) and in-hospital survival without death and PE-related shock was similar between the two groups (93% vs. 95%). In normotensive PE with oligoanuria and RV dilatation, diuretic can be safely delivered to improve systolic blood pressure and oxygenation.

The Shock Index revisited – a fast guide to transfusion requirement? A retrospective analysis on 21,853 patients derived from the TraumaRegister DGU®

IntroductionIsolated vital signs (for example, heart rate or systolic blood pressure) have been shown unreliable in the assessment of hypovolemic shock. In contrast, the Shock Index (SI), defined by the ratio of heart rate to systolic blood pressure, has been advocated to better risk-stratify patients for increased transfusion requirements and early mortality. Recently, our group has developed a novel and clinical reliable classification of hypovolemic shock based upon four classes of worsening base deficit (BD). The objective of this study was to correlate this classification to corresponding strata of SI for the rapid assessment of trauma patients in the absence of laboratory parameters.MethodsBetween 2002 and 2011, data for 21,853 adult trauma patients were retrieved from the TraumaRegister DGU® database and divided into four strata of worsening SI at emergency department arrival (group I, SI <0.6; group II, SI ≥0.6 to <1.0; group III, SI ≥1.0 to <1.4; and group IV, SI ≥1.4) and were assessed for demographics, injury characteristics, transfusion requirements, fluid resuscitation and outcomes. The four strata of worsening SI were compared with our recently suggested BD-based classification of hypovolemic shock.ResultsWorsening of SI was associated with increasing injury severity scores from 19.3 (± 12) in group I to 37.3 (± 16.8) in group IV, while mortality increased from 10.9% to 39.8%. Increments in SI paralleled increasing fluid resuscitation, vasopressor use and decreasing hemoglobin, platelet counts and Quick’s values. The number of blood units transfused increased from 1.0 (± 4.8) in group I to 21.4 (± 26.2) in group IV patients. Of patients, 31% in group III and 57% in group IV required ≥10 blood units until ICU admission. The four strata of SI discriminated transfusion requirements and massive transfusion rates equally with our recently introduced BD-based classification of hypovolemic shock.ConclusionSI upon emergency department arrival may be considered a clinical indicator of hypovolemic shock in respect to transfusion requirements, hemostatic resuscitation and mortality. The four SI groups have been shown to equal our recently suggested BD-based classification. In daily clinical practice, SI may be used to assess the presence of hypovolemic shock if point-of-care testing technology is not available.

Recumbent Cross-Training Is a Feasible and Safe Mode of Physical Activity for Significantly Motor-Impaired Adults With Cerebral Palsy

ObjectiveTo examine the feasibility and potential benefits of using recumbent cross-training for nonambulatory adults with cerebral palsy (CP). DesignObservational. SettingClinical center for CP treatment and rehabilitation. ParticipantsSignificantly motor-impaired adults with CP (N=11) with a mean age ± SD of 36.3±13.2 years and Gross Motor Function Classification System (GMFCS) levels III and IV. InterventionsParticipants completed a 40-minute session of aerobic exercise using the NuStep Recumbent Cross Trainer, in which resistance was progressively increased at 5-minute intervals. Main Outcome MeasuresEvery 5 minutes during the exercise session, heart rate, blood pressure, oxygen consumption (V˙O2), energy expenditure, and respiratory exchange ratios (RERs) were recorded along with rating of perceived exertion. Immediately after, and 24 hours postexercise, participants received a standard survey to assess levels of pain and discomfort. ResultsAll participants were able to complete the 40-minute exercise protocol. Five of the 11 participants achieved a heart rate of at least 60% maximum throughout the duration, 10 participants had a significant elevation in V˙O2 from baseline, and all participants had elevated RER values. Six participants reported pain during exercise, but only 2 reported pain after exercise was over. ConclusionsThe NuStep Recumbent Cross Trainer is a feasible exercise modality for significantly motor-impaired adults with CP, GMFCS III and IV. Moreover, this mode was sufficient to stimulate a significant cardiorespiratory response in all participants, and thus it and similar devices may serve as a viable option for aerobic exercise interventions in this population, to prevent obesity and related cardiometabolic consequences.

The Use of Heart Rate Variability in Assessing Precompetitive Stress in High-Standard Judo Athletes

The objective of this study is to examine the sensitivity to and changes in heart rate variability (HRV) in stressful situations before judo competitions and to observe the differences among judo athletes according to their competitive standards in both official and unofficial competitions. 24 (10 male and 14 female) national- and international-standard athletes were evaluated. Each participant answered the Revised Competitive State Anxiety Inventory (CSAI-2R) and their HRV was recorded both during an official and unofficial competition. The MANOVA showed significant main effects of the athlete's standard and the type of competition in CSAI-2R, in HRV time domain, in HRV frequency domain and in HRV nonlinear analysis (p<0.05). International-standard judo athletes have lower somatic anxiety, cognitive anxiety, heart rate and low-high frequency ratio than national-standard athletes (p<0.05). International-standard athletes have a higher confidence, mean RR interval, standard deviation of RR, square root of the mean squared difference of successive RR intervals, number of consecutive RR that differ by more than 5 ms, short-term variability, long-term variability, long-range scaling exponents and short-range scaling exponent than national-standard judo athletes. In conclusion, international-standard athletes show less pre-competitive anxiety than the national-standard athletes and HRV analysis is sensitive to changes in pre-competitive anxiety.