External validation of cardiac arrest-specific prognostication scores developed for early prognosis estimation after out-of-hospital cardiac arrest in a Korean multicenter cohort

We evaluated the performance of cardiac arrest-specific prognostication scores developed for outcome prediction in the early hours after out-of-hospital cardiac arrest (OHCA) in predicting long-term outcomes using independent data. The following scores were calculated for 1,163 OHCA patients who were treated with targeted temperature management (TTM) at 21 hospitals in South Korea: OHCA, cardiac arrest hospital prognosis (CAHP), C-GRApH (named on the basis of its variables), TTM risk, 5-R, NULL-PLEASE (named on the basis of its variables), Serbian quality of life long-term (SR-QOLl), cardiac arrest survival, revised post-cardiac arrest syndrome for therapeutic hypothermia (rCAST), Polish hypothermia registry (PHR) risk, and PROgnostication using LOGistic regression model for Unselected adult cardiac arrest patients in the Early stages (PROLOGUE) scores and prediction score by Aschauer et al. Their accuracies in predicting poor outcome at 6 months after OHCA were determined using the area under the receiver operating characteristic curve (AUC) and calibration belt. In the complete-case analyses, the PROLOGUE score showed the highest AUC (0.923; 95% confidence interval [CI], 0.904–0.941), whereas the SR-QOLl score had the lowest AUC (0.749; 95% CI, 0.711–0.786). The discrimination performances were similar in the analyses after multiple imputation. The PROLOGUE, TTM risk, CAHP, NULL-PLEASE, 5-R, and cardiac arrest survival scores were well calibrated. The rCAST and PHR risk scores showed acceptable overall calibration, although they showed miscalibration under the 80% CI level at extreme prediction values. The OHCA score, C-GRApH score, prediction score by Aschauer et al., and SR-QOLl score showed significant miscalibration in both complete-case (P = 0.026, 0.013, 0.005, and < 0.001, respectively) and multiple-imputation analyses (P = 0.007, 0.018, < 0.001, and < 0.001, respectively). In conclusion, the discrimination performances of the prognostication scores were all acceptable, but some showed significant miscalibration.

Effect of Epinephrine Administered during Cardiopulmonary Resuscitation on Cerebral Oxygenation after Restoration of Spontaneous Circulation in a Swine Model with a Clinically Relevant Duration of Untreated Cardiac Arrest

Severe neurological impairment was more prevalent in cardiac arrest survivors who were administered epinephrine than in those administered placebo in a randomized clinical trial; short-term reduction of brain tissue O2 tension (PbtO2) after epinephrine administration in swine following a short duration of untreated cardiac arrest has also been reported. We investigated the effects of epinephrine administered during cardiopulmonary resuscitation (CPR) on cerebral oxygenation after restoration of spontaneous circulation (ROSC) in a swine model with a clinically relevant duration of untreated cardiac arrest. After 7 min of ventricular fibrillation, 24 pigs randomly received either epinephrine or saline placebo during CPR. Parietal cortex measurements during 60-min post-resuscitation period showed that the area under the curve (AUC) for PbtO2 was smaller in the epinephrine group than in the placebo group during the initial 10-min period and subsequent 50-min period (both p < 0.05). The AUC for number of perfused cerebral capillaries was smaller in the epinephrine group during the initial 10-min period (p = 0.005), but not during the subsequent 50-min period. In conclusion, epinephrine administered during CPR reduced PbtO2 for longer than 10 min following ROSC in a swine model with a clinically relevant duration of untreated cardiac arrest.

Relationship of common hemodynamic and respiratory target parameters with brain tissue oxygen tension in the absence of hypoxemia or hypotension after cardiac arrest: A post-hoc analysis of an experimental study using a pig model

Brain tissue oxygen tension (PbtO2)-guided care, a therapeutic strategy to treat or prevent cerebral hypoxia through modifying determinants of cerebral oxygen delivery, including arterial oxygen tension (PaO2), end-tidal carbon dioxide (ETCO2), and mean arterial pressure (MAP), has recently been introduced. Studies have reported that cerebral hypoxia occurs after cardiac arrest in the absence of hypoxemia or hypotension. To obtain preliminary information on the degree to which PbtO2 is responsive to changes in the common target variables for PbtO2-guided care in conditions without hypoxemia or hypotension, we investigated the relationships between the common target variables for PbtO2-guided care and PbtO2 using data from an experimental study in which the animals did not experience hypoxemia or hypotension after resuscitation. We retrospectively analyzed 170 sets of MAP, ETCO2, PaO2, PbtO2, and cerebral microcirculation parameters obtained during the 60-min post-resuscitation period in 10 pigs resuscitated from ventricular fibrillation cardiac arrest. PbtO2 and cerebral microcirculation parameters were measured on parietal cortices exposed through burr holes. Multiple linear mixed effect models were used to test the independent effects of each variable on PbtO2. Despite the absence of arterial hypoxemia or hypotension, seven (70%) animals experienced cerebral hypoxia (defined as PbtO2 <20 mmHg). Linear mixed effect models revealed that neither MAP nor ETCO2 were related to PbtO2. PaO2 had a significant linear relationship with PbtO2 after adjusting for significant covariates (P = 0.030), but it could explain only 17.5% of the total PbtO2 variance (semi-partial R2 = 0.175; 95% confidence interval, 0.086-0.282). In conclusion, MAP and ETCO2 were not significantly related to PbtO2 in animals without hypoxemia or hypotension during the early post-resuscitation period. PaO2 had a significant linear association with PbtO2, but its ability to explain PbtO2 variance was small.

Pralidoxime-Induced Potentiation of the Pressor Effect of Adrenaline and Hastened Successful Resuscitation by Pralidoxime in a Porcine Cardiac Arrest Model

PURPOSE

Pralidoxime potentiated the pressor effect of adrenaline and facilitated restoration of spontaneous circulation (ROSC) after prolonged cardiac arrest. In this study, we hypothesised that pralidoxime would hasten ROSC in a model with a short duration of untreated ventricular fibrillation (VF). We also hypothesised that potentiation of the pressor effect of adrenaline by pralidoxime would not be accompanied by worsening of the adverse effects of adrenaline.

METHODS

After 5 min of VF, 20 pigs randomly received either pralidoxime (40 mg/kg) or saline, in combination with adrenaline, during cardiopulmonary resuscitation (CPR). Coronary perfusion pressure (CPP) during CPR, and ease of resuscitation were compared between the groups. Additionally, haemodynamic data, severity of ventricular arrhythmias, and cerebral microcirculation were measured during the 1-h post-resuscitation period. Cerebral microcirculatory blood flow and brain tissue oxygen tension (PbtO₂) were measured on parietal cortices exposed through burr holes.

RESULTS

All animals achieved ROSC. The pralidoxime group had higher CPP during CPR (P = 0.014) and required a shorter duration of CPR (P = 0.024) and smaller number of adrenaline doses (P = 0.024). During the post-resuscitation period, heart rate increased over time in the control group, and decreased steadily in the pralidoxime group. No inter-group differences were observed in the incidences of ventricular arrhythmias, cerebral microcirculatory blood flow, and PbtO₂.

CONCLUSION

Pralidoxime improved CPP and hastened ROSC in a model with a short duration of untreated VF. The potentiation of the pressor effect of adrenaline was not accompanied by the worsening of the adverse effects of adrenaline.

Effects of Different Doses of Pralidoxime Administered During Cardiopulmonary Resuscitation and the Role of α-Adrenergic Receptors in Its Pressor Action

Background

We previously reported that pralidoxime facilitated restoration of spontaneous circulation by potentiating the pressor effect of epinephrine. We determined the optimal dose of pralidoxime during cardiopulmonary resuscitation and evaluated the involvement of α‐adrenoceptors in its pressor action.

Methods and Results

Forty‐four pigs randomly received 1 of 3 doses of pralidoxime (40, 80, or 120 mg/kg) or saline placebo during cardiopulmonary resuscitation, including epinephrine administration. Pralidoxime at 40 mg/kg produced the highest coronary perfusion pressure, whereas 120 mg/kg of pralidoxime produced the lowest coronary perfusion pressure. Restoration of spontaneous circulation was attained in 4 (36.4%), 11 (100%), 9 (81.8%), and 3 (27.3%) animals in the saline, 40, 80, and 120 mg/kg groups, respectively (P<0.001). In 49 rats, arterial pressure response to 40 mg/kg of pralidoxime was determined after saline, guanethidine, phenoxybenzamine, or phentolamine pretreatment, and the response to 200 mg/kg pf pralidoxime was determined after saline, propranolol, or phentolamine pretreatment. Pralidoxime at 40 mg/kg elicited a pressor response. Phenoxybenzamine completely inhibited the pressor response, but guanethidine and phentolamine did not. The pressor response of pralidoxime was even greater after guanethidine or phentolamine pretreatment. Pralidoxime at 200 mg/kg produced an initial vasodepressor response followed by a delayed pressor response. Unlike propranolol, phentolamine eliminated the initial vasodepressor response.

Conclusions

Pralidoxime at 40 mg/kg administered with epinephrine improved restoration of spontaneous circulation rate by increasing coronary perfusion pressure in a pig model of cardiac arrest, whereas 120 mg/kg did not improve coronary perfusion pressure or restoration of spontaneous circulation rate. The pressor effect of pralidoxime was unrelated to α‐adrenoceptors and buffered by its vasodepressor action mediated by sympathoinhibition.

Pralidoxime administered during cardiopulmonary resuscitation facilitates successful resuscitation in a pig model of cardiac arrest

Pralidoxime is a common antidote for organophosphate poisoning; however, studies have also reported pralidoxime's pressor effect, which may facilitate the restoration of spontaneous circulation (ROSC) after cardiac arrest by improving coronary perfusion pressure (CPP). We investigated the immediate cardiovascular effects of pralidoxime in anaesthetised normal rats and the effects of pralidoxime administration during cardiopulmonary resuscitation (CPR) in a pig model of cardiac arrest. To evaluate the immediate cardiovascular effects of pralidoxime, seven anaesthetised normal rats received saline or pralidoxime (20 mg/kg) in a randomised crossover design, and the responses were determined using the conductance catheter technique. To evaluate the effects of pralidoxime administration during CPR, 22 pigs randomly received either 80 mg/kg of pralidoxime or an equivalent volume of saline during CPR. In the rats, pralidoxime significantly increased arterial pressure than saline (P = .044). The peak effect on arterial pressure was observed in the first minute. In a pig model of cardiac arrest, CPP during CPR was higher in the pralidoxime group than in the control group (P = .002). ROSC was attained in three animals (27.3%) in the control group and nine animals (81.8%) in the pralidoxime group (P = .010). Three animals (27.3%) in the control group and eight animals (72.2%) in the pralidoxime group survived the 6-hour period (P = .033). In conclusion, pralidoxime had a rapid onset of pressor effect. Pralidoxime administered during CPR led to significantly higher rates of ROSC and 6-hour survival by improving CPP in a pig model.

The association between lipid profiles and the neurologic outcome in patients with out-of-hospital cardiac arrest

BACKGROUND

Lipid profiles are known to be a risk factor for development of cardiovascular disease. However, the relationship between lipid profiles and outcome in out-of-hospital cardiac arrest (OHCA) survivors remains unclear. We aimed to examine the association between lipid profiles and neurologic outcome in OHCA survivors.

METHODS

This retrospective observational study included adult (≥18 years) OHCA survivors between January 2016 and December 2018. We measured patients' lipid profiles after return of spontaneous circulation (ROSC) including total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and triglyceride. The primary outcome was neurologic outcome at hospital discharge. Good neurologic outcome was defined cerebral performance categories 1 and 2.

RESULTS

A total of 182 patients were included. Of them, 57 (31.3%) were discharged with good neurologic outcomes. Median serum levels of total cholesterol (178.0 vs. 123.0 mg/dL), HDL (44.0 vs. 31.0 mg/dL), and LDL (104.0 vs. 75.0 mg/dL) were significantly higher in patients with good neurologic outcome. The area under the curves of total cholesterol, HDL, LDL, and triglyceride were 0.742 (95% confidence interval [CI], 0.672-0.803), 0.729 (95% CI, 0.658-0.792), 0.683 (95% CI, 0.610-0.750), and 0.572 (95% CI, 0.497-0.645), respectively. Total cholesterol (odds ratio [OR], 1.013; 95% CI, 1.000-1.025; p = 0.043) and HDL (OR, 1.071; 95% CI, 1.021-1.123; p = 0.005) levels were associated with good neurologic outcomes.

CONCLUSIONS

The levels of total cholesterol and HDL after ROSC were associated with good neurologic outcomes in patients with OHCA, without considering the effect of other lipid profiles simultaneously.

Turn-to-Shockable Rhythm Has Comparable Neurologic Outcomes to Initial Shockable Rhythm in Out-of-Hospital Cardiac Arrest Patients Who Underwent Targeted Temperature Management

Shockable rhythm in out-of-hospital cardiac arrest (OHCA) implies better outcome and underlying coronary stenosis. We investigated the neurologic outcome and coronary lesions between initial shockable rhythm and turn-to-shockable rhythm. This multicenter, retrospective observational study included adult nontraumatic OHCA survivors with any shockable rhythm during cardiopulmonary resuscitation (CPR) who underwent targeted temperature management between January 2010 and December 2016. Patients were divided into two groups according to the first monitored rhythm: initial shockable rhythm or turn-to-shockable rhythm. The primary outcome was good neurologic outcome at discharge based on cerebral performance categories, and the secondary outcomes were survival discharge, recurrent arrest, and coronary lesions. The two groups were matched in a 1:1 ratio using propensity score (PS). Of 426 patients, 137 and 289 patients were divided into the turn-to-shockable and initial shockable rhythm groups, respectively. Overall, 224 (52.6%) patients had good neurologic outcomes. The turn-to-shockable rhythm group had less patients with good neurologic outcome (57/137 vs. 167/289; p = 0.002) and less culprit lesions in the left anterior descending and left circumflex arteries. However, survival discharge and recurrent arrest were not different between the two groups, and the turn-to-shockable rhythm had no independent association with neurologic outcome (odds ratio, 1.874; 95% confidence interval, 0.909-3.863). In the PS-matched cohort, the turn-to-shockable rhythm group had similar good neurologic outcome (47/100 vs. 35/100, p = 0.083). Survival discharge, recurrent arrest, and coronary culprit lesions were not different between the two groups. In this PS-matched study, OHCA with any shockable rhythm during CPR had similar neurologic outcome and coronary culprit lesions, irrespective of the first monitored rhythm.

Effect of pralidoxime on coronary perfusion pressure during cardiopulmonary resuscitation in a pig model

Objective

Pralidoxime is widely used for the treatment of organophosphate poisoning. Multiple studies have reported its vasoconstrictive property, which may facilitate the restoration of spontaneous circulation (ROSC) after cardiac arrest by increasing the coronary perfusion pressure (CPP). 2,3-Butanedione monoxime, which belongs to the same oxime family, has been shown to facilitate ROSC by reducing left ventricular ischemic contracture. Because pralidoxime and 2,3-butanedione monoxime have several common mechanisms of action, both drugs may have similar effects on ischemic contracture. Thus, we investigated the effects of pralidoxime administration during cardiopulmonary resuscitation in a pig model with a focus on ischemic contracture and CPP.

Methods

After 14 minutes of untreated ventricular fibrillation, followed by 8 minutes of basic life support, 16 pigs randomly received either 80 mg/kg of pralidoxime (pralidoxime group) or an equivalent volume of saline (control group) during advanced cardiovascular life support (ACLS).

Results

Mixed-model analyses of left ventricular wall thickness and chamber area during ACLS revealed no significant group effects or group-time interactions, whereas a mixed-model analysis of the CPP during ACLS revealed a significant group effect (P=0.038) and group-time interaction (P<0.001). Post-hoc analyses revealed significant increases in CPP in the pralidoxime group, starting at 5 minutes after pralidoxime administration. No animal, except one in the pralidoxime group, achieved ROSC; thus, the rate of ROSC did not differ between the two groups.

Conclusion

In a pig model of cardiac arrest, pralidoxime administered during cardiopulmonary resuscitation did not reduce ischemic contracture; however, it significantly improved CPP.

Relationship between ventricular characteristics on brain computed tomography and 6-month neurologic outcome in cardiac arrest survivors who underwent targeted temperature management

AIM OF THE STUDY

Brain swelling after cardiac arrest may affect the ventricles. We aimed to investigate the prognostic performance of ventricular characteristics on brain computed tomography (CT) in cardiac arrest survivors who underwent targeted temperature management (TTM).

METHODS

This retrospective cohort study included adult comatose cardiac arrest survivors who underwent brain CT scan within 24 h after resuscitation and underwent TTM from 2014 to 2016. The ventricular areas (lateral, third, and fourth ventricle), distances between the anterior horns of the lateral ventricle (LV) and the posterior horns of the LV, and maximal internal diameter of the skull were measured. Grey-to-white matter ratio (GWR), Evans' index, and relative LV area were calculated. The primary outcome was a 6-month neurologic outcome.

RESULTS

Of 258 patients, 176 (68.2%) had an unfavourable neurologic outcome. GWR, LV area, third ventricle area, distance between the anterior horns of the LV, distance between the posterior horns of the LV, Evans' index, and relative LV area were different between neurologic outcome groups. Evans' index (0.683; 95% confidence interval [CI], 0.623-0.739) and relative LV area (0.670; 95% CI, 0.609-0.727) had higher value of area under the curve than the other ventricular characteristics and showed prognostic performance comparable with GWR (0.600; 95% CI, 0.538-0.661). All ventricular characteristics and GWR were not independently associated with neurologic outcome after adjusting for covariates.

CONCLUSION

Ventricular characteristics on brain CT were associated with 6 months neurologic outcome in cardiac arrest survivors. Ventricular characteristics were objective measures that had comparable prognostic performance with GWR.

Effect of one-lung ventilation on end-tidal carbon dioxide during cardiopulmonary resuscitation in a pig model of cardiac arrest

Unrecognized endobronchial intubation frequently occurs after emergency intubation. However, no study has evaluated the effect of one-lung ventilation on end-tidal carbon dioxide (ETCO₂) during cardiopulmonary resuscitation (CPR). We compared the hemodynamic parameters, blood gases, and ETCO₂ during one-lung ventilation with those during conventional two-lung ventilation in a pig model of CPR, to determine the effect of the former on ETCO₂. A randomized crossover study was conducted in 12 pigs intubated with double-lumen endobronchial tube to achieve lung separation. During CPR, the animals underwent three 5-min ventilation trials based on a randomized crossover design: left-lung, right-lung, or two-lung ventilation. Arterial blood gases were measured at the end of each ventilation trial. Ventilation was provided using the same tidal volume throughout the ventilation trials. Comparison using generalized linear mixed model revealed no significant group effects with respect to aortic pressure, coronary perfusion pressure, and carotid blood flow; however, significant group effect in terms of ETCO₂ was found (P < 0.001). In the post hoc analyses, ETCO₂ was lower during the right-lung ventilation than during the two-lung (P = 0.006) or left-lung ventilation (P < 0.001). However, no difference in ETCO₂ was detected between the left-lung and two-lung ventilations. The partial pressure of arterial carbon dioxide (PaCO₂), partial pressure of arterial oxygen (PaO₂), and oxygen saturation (SaO₂) differed among the three types of ventilation (P = 0.003, P = 0.001, and P = 0.001, respectively). The post hoc analyses revealed a higher PaCO₂, lower PaO₂, and lower SaO₂ during right-lung ventilation than during two-lung or left-lung ventilation. However, the levels of these blood gases did not differ between the left-lung and two-lung ventilations. In a pig model of CPR, ETCO₂ was significantly lower during right-lung ventilation than during two-lung ventilation. However, interestingly, ETCO₂ during left-lung ventilation was comparable to that during two-lung ventilation.

Neuromuscular blockade requirement is associated with good neurologic outcome in cardiac arrest survivors treated with targeted temperature management

PURPOSE

We examined the association between neuromuscular blockade (NMB) requirements and outcomes and lactate clearance in cardiac arrest survivors treated with targeted temperature management (TTM).

METHODS

We included consecutive adult cardiac arrest survivors treated with TTM between 2012 and 2015. NMB use was categorized into 3 groups: no NMB, bolus NMB (intermittent bolus use), and continuous NMB (continuous infusion). Serum lactate levels were measured on admission and at 12h, 24h, and 48h after admission. The primary outcome was neurologic outcome at discharge. The secondary outcomes were in-hospital mortality and lactate clearance.

RESULTS

In total, 309 patients were included. Of these, 206 (66.7%) and 73 (23.6%) were discharged with poor neurologic outcome and death, respectively. Multivariate analysis revealed that continuous NMB, as opposed to no NMB use, was associated with decreased poor neurologic outcomes (odds ratio [OR], 0.317; 95% confidence interval [CI], 0.124-0.815) and decreased in-hospital mortality (OR, 0.414; 95% CI, 0.183-0.941). There were no differences in lactate clearance between the NMB groups.

CONCLUSION

Continuous NMB requirement was associated with improved neurologic outcome and decreased in-hospital mortality in cardiac arrest survivors treated with TTM. The NMB requirement was not associated with lactate clearance.

Relationship between age and outcomes of comatose cardiac arrest survivors in a setting without withdrawal of life support

AIM OF THE STUDY

Previous studies on the relationship between age and outcomes after cardiac arrest were performed in settings where the majority of patients died after the withdrawal of life support (WLS). We examined the association between age and outcomes of comatose cardiac arrest survivors in a setting where WLS was not performed.

METHODS

This single-centre retrospective observational study included adult comatose cardiac arrest survivors treated with targeted temperature management. In Korea, WLS is not permitted unless the patient is pronounced brain-dead. The primary outcome was poor neurologic outcome at hospital discharge, defined as Cerebral Performance Categories scores of 3-5. The secondary outcomes were in-hospital and six-month mortalities.

RESULTS

A total of 534 patients were analysed. In multivariate analysis, age was not associated with in-hospital mortality (odds ratio [OR], 1.01; 95% confidence interval [CI], 0.99-1.02), but it was independently associated with neurologic outcome at hospital discharge (OR, 1.03; 95% CI, 1.02-1.05) and six-month mortality (OR, 1.05; 95% CI, 1.03-1.07). When age was categorised into 10-year intervals, age groups less than 61-70 years had significantly lower OR for poor neurologic outcome compared with the reference group (61-70 years), while the OR for poor neurologic outcome in age groups greater than 70 years did not differ from that in the reference group.

CONCLUSION

In a setting where WLS is not performed, we found that age was not associated with in-hospital mortality but was independently associated with neurologic outcome at hospital discharge and six-month mortality.

Relationship between timing of cooling and outcomes in adult comatose cardiac arrest patients treated with targeted temperature management

AIM OF THE STUDY

Studies examining associations between time to target temperature and outcomes in cardiac arrest patients who underwent targeted temperature management (TTM) have shown inconsistent results. We examined these associations separately for time from restoration of spontaneous circulation to TTM initiation (pre-induction time) and time from TTM initiation to target temperature (induction time). Furthermore, we examined whether critical time thresholds exist if there is an association.

METHODS

This was a single-centre retrospective observational study including adult cardiac arrest patients treated with TTM from 2008 to 2015. We tested the associations of pre-induction time and induction time with outcomes at hospital discharge using multivariate logistic regression analysis. We then performed additional multivariate analyses, each with the significant timing variable at different binary cutoffs.

RESULTS

A total of 515 patients were analysed. At hospital discharge, 357 patients (69.3%) were alive, of whom 161 (31.3%) had a favourable neurologic outcome. In multivariate analysis, a shorter pre-induction time was independently associated with a favourable neurologic outcome (odds ratio [OR], 1.110; 95% confidence interval [CI], 1.025-1.202), whereas the induction time was not (OR, 0.954; 95% CI, 0.852-1.067). We found two pre-induction time thresholds (120 and 360min) that were associated with neurologic outcome.

CONCLUSION

We found that a shorter pre-induction time was independently associated with a favorable neurologic outcome at hospital discharge, whereas induction time was not. We also found two time thresholds at 120 and 360min, after which initiation of cooling was associated with a worse neurologic outcome.

Correlation between initial serum levels of lactate after return of spontaneous circulation and survival and neurological outcomes in patients who undergo therapeutic hypothermia after cardiac arrest

OBJECTIVES

We analysed the relationship between serum levels of lactate within 1h of return of spontaneous circulation (ROSC) and survival and neurological outcomes in patients who underwent therapeutic hypothermia (TH).

METHODS

This was a multi-centre retrospective and observational study that examined data from the first Korean Hypothermia Network (KORHN) registry from 2007 to 2012. The inclusion criteria were out-of-hospital cardiac arrest (OHCA) and examination of serum levels of lactate within 1h after ROSC, taken from KORHN registry data. The primary endpoint was survival outcome at hospital discharge, and the secondary endpoint was poor neurological outcome (Cerebral Performance Category, CPC, 3-5) at hospital discharge. Initial lactate levels and other variables collected within 1h of ROSC were analysed via multivariable logistic regression.

RESULTS

Data from 930 cardiac arrest patients who underwent TH were collected from the KORHN registry. In a total of 443 patients, serum levels of lactate were examined within 1h of ROSC. In-hospital mortality was 289/443 (65.24%), and 347/443 (78.33%) of the patients had CPCs of 3-5 upon hospital discharge. The odds ratios of lactate levels for CPC and in-hospital mortality were 1.072 (95% confidence interval (CI) 1.026-1.121) and 1.087 (95% CI=1.031-1.147), respectively, based on multivariate ordinal logistic regression analyses.

CONCLUSION

High levels of lactate in serum measured within 1h of ROSC are associated with hospital mortality and high CPC scores in cardiac arrest patients treated with TH.

Impact of case volume on outcome and performance of targeted temperature management in out-of-hospital cardiac arrest survivors

PURPOSE

This study aimed to determine the effect of case volume on targeted temperature management (TTM) performance, incidence of adverse events, and neurologic outcome in comatose out-of-hospital cardiac arrest (OHCA) survivors treated with TTM.

METHODS

We used a Web-based, multicenter registry (Korean Hypothermia Network registry), to which 24 hospitals throughout the Republic of Korea participated to study adult (≥18 years) comatose out-of-hospital cardiac arrest patients treated with TTM between 2007 and 2012. The primary outcome was neurologic outcome at hospital discharge. The secondary outcomes were inhospital mortality, TTM performance, and adverse events. We extracted propensity-matched cohorts to control for bias. Multivariate logistic regression analysis was performed to assess independent risk factors for neurologic outcome.

RESULTS

A total of 901 patients were included in this study; 544 (60.4%) survived to hospital discharge, and 248 (27.5%) were discharged with good neurologic outcome. The high-volume hospitals initiated TTM significantly earlier and had lower rates of hyperglycemia, bleeding, hypotension, and rebound hyperthermia. However, neurologic outcome and inhospital mortality were comparable between high-volume (27.7% and 44.6%, respectively) and low-volume hospitals (21.1% and 40.5%) in the propensity-matched cohorts. The adjusted odds ratio for the high-volume hospitals compared with low-volume hospitals was 1.506 (95% confidence interval, 0.875-2.592) for poor neurologic outcome.

CONCLUSIONS

Higher TTM case volume was significantly associated with early initiation of TTM and lower incidence of adverse events. However, case volume had no association with neurologic outcome and inhospital mortality.

Effects of potassium/lidocaine-induced cardiac standstill during cardiopulmonary resuscitation in a pig model of prolonged ventricular fibrillation

OBJECTIVES

Several studies in patients who underwent open heart surgery found that myocardial ischemic damage was reduced by potassium cardioplegia combined with lidocaine infusion. The authors evaluated the effects of potassium/lidocaine-induced cardiac standstill during conventional cardiopulmonary resuscitation (CPR) on myocardial injury and left ventricular dysfunction after resuscitation from prolonged ventricular fibrillation (VF) cardiac arrest in a pig model.

METHODS

Ventricular fibrillation was induced in 16 pigs, and circulatory arrest was maintained for 14 minutes. Animals were then resuscitated by standard CPR. Animals were randomized at the start of CPR to receive 20 mL of saline (control group) or 0.9 mEq/kg potassium chloride and 1.2 mg/kg lidocaine diluted to 20 mL (K-lido group).

RESULTS

Seven animals in each group achieved return of spontaneous circulation (ROSC; p=1.000). Four of the K-lido group animals (50%) achieved ROSC without countershock. Resuscitated animals in the K-lido group required fewer countershocks (p=0.004), smaller doses of epinephrine (p=0.009), and shorter durations of CPR (p=0.004) than did the control group. The uncorrected troponin-I at 4 hours after ROSC was lower in the K-lido group compared with the control group (2.82 ng/mL, 95% confidence interval [CI]=1.07 to 3.38 ng/mL vs. 6.55 ng/mL, 95% CI=4.84 to 13.30 ng/mL; p=0.025), although the difference was not significant after Bonferroni correction. The magnitude of reduction in left ventricular ejection fraction (LVEF) between baseline and 1 hour after ROSC was significantly lower in the K-lido group (26.5%, SD±6.1% vs. 39.1%, SD±6.8%; p=0.004).

CONCLUSIONS

In a pig model of untreated VF cardiac arrest for 14 minutes, resuscitation with potassium/lidocaine-induced cardiac standstill during conventional CPR tended to reduce myocardial injury and decreased the severity of postresuscitation myocardial dysfunction significantly.

Confirmation of intraosseous cannula placement based on pressure measured at the cannula during squeezing the extremity in a piglet model

AIM OF THE STUDY

We sought to assess the reliability of the method using the pressure measured at the intraosseous (IO) cannula while squeezing the involved limb (P(squeezing)) in determining the position of the IO needle and to compare its performance with that of the traditional confirmation method.

METHODS

Eighty limbs of twenty domestic swine were assigned to one of three conditions regarding the position of the IO needle; correct placement (n=40), incorrect placement in which the IO needle was placed into the subcutaneous space without entering the bone (incorrect-subcutaneous placement, n=20), or incorrect placement in which the IO needle passed entirely through the bone (incorrect-penetrating placement, n=20). A blinded investigator randomly identified the position of the needle by the traditional method or test method using P(squeezing). If P(squeezing) was 80 mmHg or higher, the IO cannula was regarded as incorrectly placed.

RESULTS

P(squeezing) was higher in incorrect placements (176.0 mmHg (130.0-195.0)) compared with that in correct placements (27.0 mmHg (20.0-34.0)) (p<0.001). The test method correctly identified all 40 placements, but the traditional method was incorrect for one (5%) of 20 correct placements (p=1.000) and 7 (35%) of 20 incorrect placements (p=0.008). In incorrect placements, false positive results occurred mainly in incorrect-penetrating placements.

CONCLUSION

We suggest that the method using the pressure measured at the IO cannula can be used when there is uncertainty about the position of the IO cannula after determination using traditional methods.

The performances of standard and ResMed masks during bag-valve-mask ventilation

BACKGROUND

A tight mask seal is frequently difficult to obtain and maintain during single-rescuer bag-valve-mask (BVM) ventilation. The ResMed mask (Bella Vista, NSW, Australia) is a continuous-positive-airway-pressure mask (CM) designed for noninvasive ventilation.

OBJECTIVE

In this study, we compared the ventilation performances of a standard mask (SM) and a ResMed CM using a simulation manikin in an out-of-hospital single-rescuer BVM ventilation scenario.

METHODS

Thirty emergency medical technicians (EMTs) performed two 2-minute attempts to ventilate a simulation manikin using BVM ventilation, alternatively, with the SM or the ResMed CM in a randomized order. Ventilation parameters including tidal volume and peak airway pressure were measured using computer analysis software connected to the simulation manikin. Successful volume delivery was defined as delivery of 440-540 mL of tidal volume in accord with present cardiopulmonary resuscitation guidelines.

RESULTS

BVM ventilation using the ResMed CM produced higher mean (± standard deviation) tidal volumes (452 ± 50 mL vs. 394 ± 113 mL, p = 0.014) and had a higher proportion of successful volume deliveries (65.3% vs. 26.7%, p < 0.001) than that using the SM. Peak airway pressure was higher in BVM ventilation using the ResMed CM (p = 0.035). Stomach insufflation did not occur during either method. Twenty-nine of the participants (96.7%) preferred BVM ventilation using the ResMed CM.

CONCLUSIONS

BVM ventilations using ResMed CM resulted in a significantly higher proportion of successful volume deliveries meeting the currently recommended range of tidal volume. Clinical studies are needed to determine the value of the ResMed CM for BVM ventilation.

Potassium induced cardiac standstill during conventional cardiopulmonary resuscitation in a pig model of prolonged ventricular fibrillation cardiac arrest: a feasibility study

AIM OF THE STUDY

Potassium-based cardioplegia has been the gold standard for cardioprotection during cardiac surgery. We sought to evaluate the feasibility and the effects of potassium-induced cardiac standstill during conventional cardiopulmonary resuscitation (CPR) in a pig model of prolonged ventricular fibrillation (VF).

METHODS

VF was induced in 20 pigs, and circulatory arrest was maintained for 14 min. Animals were then resuscitated by standard CPR. Coincident with the start of CPR, 20 ml of saline (control group) or 0.9 mequiv.kg(-1) of potassium chloride diluted to 20 ml (potassium group) was administered into right atrium.

RESULTS

Administration of potassium resulted in asystole lasting for 1.0 min (0.2) in the potassium group animals. VF reappeared in all but one animal, in which wide QRS complex bradycardia followed. Restoration of spontaneous circulation (ROSC) was attained in two animals (20%) in the control group and in seven animals (70%) in the potassium group (p=0.070). Resuscitated animals in the potassium group required fewer countershocks (3, 4 vs. 2 (1-2)), smaller doses of adrenaline (1.84, 1.84 vs. 0.94 (0.90-1.00)mg), and shorter duration of CPR (8, 10 vs. 4.0 (4.0-4.0)min) than did the control group. Potassium concentrations normalised rapidly after ROSC in both groups, and the potassium concentrations at 5 min (5.5, 6.6 vs. 6.8 (6.5-7.8)mequiv.l(-1)) and 4h (4.9, 5.4 vs. 5.9 (5.1-6.4)mequiv.l(-1)) after ROSC were similar in the both groups.

CONCLUSION

In a pig model of untreated VF cardiac arrest for 14 min, resuscitation with potassium-induced cardiac standstill during conventional CPR was found to be feasible.

Gene expression profiling of mouse aborted uterus induced by lipopolysac charide

To identify genes that participate in the abortion process, normal pregnant uteri were compared to lipopolysaccharide (LPS)-induced abortion uteri. At day 6 of pregnancy, mice were treated with LPS at various time points to induce an abortion. Total RNAs were applied to a cDNA microarray to analyze genes with altered expression. At the early stage (2 hours) of LPS-induced abortion, upregulated genes were mainly composed of immune responsive genes, including Ccl4, Ccl2, Cxcl13, Gbp3, Gbp2, Mx2, H2-Eb1, Irf1 and Ifi203. Genes related to toll-like receptor signaling were also overexpressed. At late stages of abortion (12-24 hours), many genes were suppressed rather than activated, and these were mainly related to the extracellular matrix, cytoskeleton, and anti-apoptosis. Altered expression of several selected genes was confirmed by real time reverse transcription-polymerase chain reaction. The results demonstrated that many known genes were altered in the LPS-treated pregnant uterus, implying that the molecular mechanisms of the genes involved in LPS-induced abortion are complicated. Further analysis of this expression profile will help our understanding of the pathophysiological basis for abortion.

Sustained manual abdominal compression during cardiopulmonary resuscitation in a pig model: a preliminary investigation

OBJECTIVES

The present study was undertaken to determine whether sustained manual abdominal compression (SMAC) using left paramedian compression technique can improve coronary perfusion pressure (CPP) during cardiopulmonary resuscitation (CPR) and resuscitation outcomes without causing liver laceration.

METHODS

Ventricular fibrillation was induced in 14 pigs, and circulatory arrest was maintained for 6 min. Animals were resuscitated either by standard CPR (control group) or by standard CPR with SMAC (SMAC-CPR group).

RESULTS

Mean blood pressure, aortic diastolic pressure and right atrial diastolic pressure in the SMAC-CPR group were significantly greater than in the control group throughout simulated basic life support. However, since the increases in aortic and right atrial diastolic pressures were similar, no significant intergroup difference was found in terms of CPP. Return of spontaneous circulation (ROSC) was attained in four of seven animals in the control group and in six of seven animals in the SMAC-CPR group (p = 0.55). Three animals in the control group and four in the SMAC-CPR group survived 24 h after ROSC (p = 1.00). Two of the seven animals in the SMAC-CPR group had a ruptured liver, but no such injury occurred in the control group.

CONCLUSIONS

SMAC using left paramedian compression technique failed to improve CPP during CPR and resuscitation outcomes. Furthermore, this method could not avoid liver laceration.

Variable effects of high-dose adrenaline relative to standard-dose adrenaline on resuscitation outcomes according to cardiac arrest duration

AIM OF THE STUDY

Adjustment of adrenaline (epinephrine) dosage according to cardiac arrest (CA) duration, rather than administering the same dose, may theoretically improve resuscitation outcomes. We evaluated variable effects of high-dose adrenaline (HDA) relative to standard-dose adrenaline (SDA) on resuscitation outcomes according to CA duration.

METHODS

Twenty-eight male domestic pigs were randomised to the following 4 groups according to the dosage of adrenaline (SDA 0.02 mg/kg vs. HDA 0.2mg/kg) and duration of CA before beginning cardiopulmonary resuscitation (CPR): 6 min SDA, 6 min HDA, 13 min SDA, or 13 min HDA. After the predetermined duration of untreated ventricular fibrillation, CPR was provided.

RESULTS

All animals in the 6 min SDA, 6 min HDA, and 13 min HDA groups were successfully resuscitated, while only 4 of 7 pigs in the 13 min SDA group were successfully resuscitated (p=0.043). HDA groups showed higher right atrial pressure, more frequent ventricular ectopic beats, higher blood glucose, higher troponin-I, and more severe metabolic acidosis than SDA groups. Animals of 13 min groups showed more severe metabolic acidosis and higher troponin-I than animals of 6 min groups. All successfully resuscitated animals, except two animals in the 13 min HDA group, survived for 7 days (p=0.121). Neurologic deficit score was not affected by the dose of adrenaline.

CONCLUSION

HDA showed benefit in achieving restoration of spontaneous circulation in 13 min CA, when compared with 6 min CA. However, this benefit did not translate into improved long-term survival or neurologic outcome.

A case of iatrogenic ilio-iliac arteriovenous fistula after percutaneous cardiopulmonary support in a patient with a tortuous iliac artery

Percutaneous cardiopulmonary support (PCPS) has repeatedly been used with success as a tool for resuscitation in various life-threatening emergencies. PCPS-related vascular injuries are common, but ilio-iliac arteriovenous fistula (AVF) formation after PCPS has not been reported so far. We experienced a case of iatrogenic ilio-iliac AVF after PCPS, in which association between iliac artery tortuosity and AVF formation was strongly suspected. This case suggests that the risk of iatrogenic iliac AVF should be considered when PCPS is performed, especially in elderly patients whose arteries are frequently tortuous.

Augmentation of the cooling capacity of refrigerated fluid by minimizing heat gain of the fluid using a simple method of cold insulation

OBJECTIVES

This study was undertaken to determine how rapidly refrigerated fluids gain heat during bolus infusion and to determine whether the refrigerated fluids could be kept cold by a simple cold-insulation method.

METHODS

One liter of refrigerated fluid was run through either a 16-gauge catheter (16G(-) and 16G(+) groups) or an 18-gauge catheter (18G(-) and 18G(+) groups) while monitoring the temperature in the fluid bag and the outflow site. In the 16G(+) and the 18G(+) groups, the fluid bag was placed with an ice pack inside an insulating sleeve during the fluid run.

RESULTS

In the 16G(-) and the 18G(-) groups, the outflow temperature increased to 10-12 degrees C during the fluid run. Meanwhile, outflow temperatures in the 16G(+) and the 18G(+) groups remained below 4.6 and 6.8 degrees C, respectively. The temperatures differed significantly between the 16G(-) and the 16G(+) groups (p < 0.001) and between the 18G(-) and the 18G(+) groups (p < 0.001), respectively.

CONCLUSIONS

Substantial heat gain occurred in the refrigerated fluid even during the relatively short duration of bolus infusion. The heat gain could, however, be easily minimized by cold insulation of the fluid bag.

Caustic injury: can CT grading system enable prediction of esophageal stricture?

BACKGROUND

The aim of this study was to test the utility of our computed tomography (CT) grading system, compared with endoscopy, for association with the development of esophageal stricture in patients with caustic ingestion.

METHODS

This retrospective case series involved 49 patients with caustic ingestion from 1998 to 2009. The degree of esophageal damage was graded using a scoring system based on the extent of esophageal wall edema and the damage in adjacent tissue as seen on thoracoabdominal CT scans. The presence of esophageal stricture was established by esophagography. Diagnostic performance was compared using receiver operating characteristic (ROC) analysis. Sensitivity and specificity were calculated for the grading system.

RESULTS

The CT grading score results showed that grade III was the most common injury (20 cases, 40.8%), followed by grade IV (14 cases, 28.6%), grade II (9 cases, 18.4%), and grade I (6 cases, 12.2%). In addition, damage to the esophagus was significantly correlated with esophageal stricture when the extent of damage approached grades III and IV (p < 0.001). The CT grading system for esophageal stricture resulted in a slightly larger area under the receiver operating characteristic curve (0.90) compared with endoscopic grading system (0.79). The sensitivity and specificity of CT grading system were moderately higher than those of endoscopic grading system.

CONCLUSION

Assessment of the degree of esophageal damage using CT, a noninvasive modality, in patients who visit the emergency department following caustic ingestion should be useful in estimating the occurrence of complications including esophageal stricture.

Distribution and three-dimensional appearance of the interstitial cells of Cajal in the rat stomach and duodenum

The relationship between the interstitial cells of Cajal (ICC) and enteric nerves or smooth muscles cells is not fully defined. Presently, distribution and appearance of ICC in the rat stomach and duodenum was studied by immunohistochemistry, electron microscopy, and three-dimensional reconstruction. c-kit expressing ICC were regularly observed in the Auerbach's myenteric plexus (AP) of the stomach and duodenum. ICC in stomach and duodenum muscle layers was dissimilarly distributed. c-kit immunoreactive cells were sparsely distributed in the stomach circular muscle layer but were abundant in the duodenum deep muscular plexus (DMP). Electron microscopy revealed that stomach ICC-AP were irregular ovals with few cytoplasmic processes, and possessed an electron-dense cytoplasm, numerous mitochondria, intermediate filaments, and caveolae. Duodenum and stomach ICC-AP were similar in appearance. Ultrastructure observations and three-dimensional reconstructions revealed ICC-AP processes wrapping the nerve fibers and projecting into the space between smooth muscle cells. While ICC-AP was occasionally close to enteric nerves or smooth muscle cells, no connections were observed. ICC-DMP in duodenum was elongated and adopted the same cell axis orientation as the circular muscle cells. Unlike ICC-AP, ICC-DMP formed gap junctions with smooth muscle cells and had close contact with nerves. These results indicate that ICC-AP is regularly distributed in stomach and duodenum, while ICC-DMP is exclusively located in the duodenum. ICC-DMP, which possess gap junctions and closely contacts nerves, may participate in neuromuscular transmission.

Rapidly induced selective cerebral hypothermia using a cold carotid arterial flush during cardiac arrest in a dog model

PURPOSE

The present study was undertaken to determine whether flushing the carotid artery with normal saline at 4 degrees C (hypothermic carotid arterial flush, HCAF) during cardiac arrest can achieve selective cerebral hypothermia rapidly during cardiac arrest and improve cerebral outcome.

METHODS

Ventricular fibrillation (VF) was induced in fourteen dogs and circulatory arrest was maintained for 9 min. Dogs were then resuscitated by cardiopulmonary resuscitation. The dogs were divided into two groups; a control group (n=7), which underwent precisely the same procedure as the experimental group but not HCAF, and an experimental group (HCAF group; n=7), which received HCAF from 8 min after the onset of VF.

RESULTS

Two dogs in the control group and in the HCAF group died within 72 h after the recovery of spontaneous circulation (ROSC) due to extracerebral complications. The remaining 10 dogs survived to final evaluation at 72 h post-ROSC. In the HCAF group, tympanic temperature decreased from 37.7 degrees C (37.5-37.8) to 34 degrees C in 1 min (1-1.5) from the start of HCAF and was maintained below 34 degrees C until 6.5 min (3-12) after the start of HCAF, whereas oesophageal and rectal temperatures were maintained above 35 degrees C. Neurological deficit scores (0-100%) at 72 h post-ROSC were 42.4% (27.0-80.6) in the control group and 18.4% (14.0-36.0) in the HCAF group (p<0.05).

CONCLUSION

HCAF induced selective cerebral hypothermia rapidly during cardiac arrest and improved neurological deficit scores after 9 min of no blood flow in the described canine cardiac arrest model.

Hemorrhagic gastritis and gas emboli after ingesting 3% hydrogen peroxide

It is well known that ingestion of low concentrations of hydrogen peroxide is usually nontoxic; this does not produce gas embolism and is only a mild irritant to the gastrointestinal tract. We report the case of a 25-year-old woman who ingested one mouthful of 3% hydrogen peroxide and presented to the Emergency Department with persistent vomiting and epigastric pain. The radiographic evaluation found portal venous gas emboli. In addition, upper gastrointestinal endoscopy performed 2 h after ingestion revealed diffuse hemorrhagic gastritis. She showed a decrease of hemoglobin concentration and a positive test result for occult blood in stool. She was observed for 14 days and discharged. Follow-up endoscopy showed erythematous gastritis. This case illustrates that a low concentration of hydrogen peroxide can cause portal venous gas embolism and severe gastrointestinal injuries even if only a small amount is ingested.

Analysis of colonoscopic findings in the differential diagnosis between intestinal tuberculosis and Crohn's disease

BACKGROUND AND STUDY AIMS

Intestinal tuberculosis and Crohn's disease are chronic inflammatory bowel disorders that are difficult to differentiate from one another. This study aimed to evaluate the diagnostic value of various colonoscopic findings in the differential diagnosis between intestinal tuberculosis and Crohn's disease.

PATIENTS AND METHODS

Colonoscopic findings on initial work-up were prospectively recorded in patients with an initial diagnosis of either intestinal tuberculosis or Crohn's disease. These findings were analyzed after a final diagnosis of intestinal tuberculosis (n = 44) or Crohn's disease (n = 44) had been made after follow-up.

RESULTS

Four parameters (anorectal lesions, longitudinal ulcers, aphthous ulcers, and cobblestone appearance) were significantly more common in patients with Crohn's disease than in patients with intestinal tuberculosis. Four other parameters (involvement of fewer than four segments, a patulous ileocecal valve, transverse ulcers, and scars or pseudopolyps) were observed more frequently in patients with intestinal tuberculosis than in patients with Crohn's disease. We hypothesized that a diagnosis of Crohn's disease could be made when the number of parameters characteristic of Crohn's disease was higher than the number of parameters characteristic of intestinal tuberculosis, and vice versa. Making these assumptions, we calculated that the diagnosis of either intestinal tuberculosis or Crohn's disease would have been made made correctly in 77 of our 88 patients (87.5 %), incorrectly in seven patients (8.0 %), and would not have been made in four patients (4.5 %).

CONCLUSIONS

A systematic analysis of colonoscopic findings is very useful in the differential diagnosis between intestinal tuberculosis and Crohn's disease.

Primary colon lymphoma in Korea: a KASID (Korean Association for the Study of Intestinal Diseases) Study

Although almost all primary colorectal lymphomas are of B-cell lineage in Western countries, primary colorectal T-cell lymphomas are not uncommon in the East. The aim of this study was to review the clinical characteristics and treatment outcomes of primary colorectal lymphomas, with special emphasis on the differences between T-cell and B-cell lymphomas. Ninety-five cases of primary colorectal lymphomas that satisfied Dawson's criteria were identified from the clinical databases of 13 university hospitals in Korea. The mean age at the time of presentation was 51.1 years and the male:female ratio was 64:31. The clinical information, including endoscopic and histological characteristics, was retrospectively analyzed. Of the primary colorectal lymphomas, 78 cases (82.1%) were of B-lineage and 17 cases (17.9%) were of T-cell lineage. Patients with T-cell lymphomas presented at a younger age than patients with B-cell lymphomas (42.8 vs 52.9 years, respectively; P = 0.016). The most common presenting symptom was abdominal pain (87.1%) for B-cell lymphomas, whereas hematochezia or night fever was more common for T-cell lymphomas (52.9% and 35.3%, respectively). The most common endoscopic type was fungating mass (54.0%) for B-cell lymphomas and ulcerative/ulcero-infiltrative lesions (80.0%) for T-cell lymphomas. Intussusception was more common in B-cell lymphomas than in T-cell lymphomas (30.8% vs 5.9%, respectively; P = 0.035), but perforation was more common in T-cell lymphomas than in B-cell lymphomas (23.5% vs 3.8%, respectively; P = 0.005). The prognosis was significantly worse for T-cell lymphomas than for B-cell lymphomas (P = 0.002). Primary colorectal T-cell lymphomas are characterized by multifocal ulcerative lesions in relatively young patients, a high rate of hematochezia, fever, or perforation, and a poor prognosis even for cases of localized disease.

Accuracy of magnetic resonance cholangiopancreatography for locating hepatolithiasis and detecting accompanying biliary strictures

BACKGROUND AND STUDY AIMS

Magnetic resonance cholangiopancreatography (MRCP) is rapidly replacing diagnostic endoscopic retrograde cholangiopancreatography (ERCP) in various pancreaticobiliary diseases. This study was designed to evaluate the accuracy of MRCP in detection of hepatolithiasis and accompanying biliary strictures.

PATIENTS AND METHODS

A prospective study over 2 years was conducted in 66 patients with primary intrahepatic stones. All patients with hepatolithiasis underwent percutaneous transhepatic cholangioscopy (PTC) within 2 weeks of the MRCP examination. The MRCP findings were compared with those of PTC as the reference standard for assessing the location of intrahepatic stones and the presence or absence of accompanying biliary strictures.

RESULTS

The sensitivity, specificity, and accuracy of MRCP for detecting and locating intrahepatic stones were 97 %, 99 %, and 98 %, respectively. The sensitivity, specificity, and accuracy of MRCP for detecting and locating intrahepatic bile duct strictures were 93 %, 97 %, and 97 %, respectively. During PTC, six of the 66 patients (9 %) were found on histology to have intraductal cholangiocarcinoma in stone-bearing ducts, which had not been suspected on MRCP.

CONCLUSIONS

In this study, MRCP allowed intrahepatic stones and accompanying biliary strictures to be located accurately. MRCP may therefore be able to replace diagnostic ERCP in patients with primary intrahepatic stones. However, MRCP had a limited ability to reveal concurrent intraductal cholangiocarcinoma associated with hepatolithiasis.

Atypical endoscopic features of rectal carcinoids

BACKGROUND AND STUDY AIMS

It is not normally difficult to diagnose carcinoid tumors (well-differentiated endocrine neoplasms) of the rectum endoscopically, as they usually have a characteristic appearance. However, little is known about the atypical endoscopic findings in some rectal carcinoids and the present study was performed to analyze these.

PATIENTS AND METHODS

The endoscopic findings in 67 consecutive patients with rectal carcinoids (37 men, 30 women; age range 23 - 76) were analyzed retrospectively.

RESULTS

Tumor size ranged from 2 mm to 30 mm (average 7.4 mm). Of the 67 patients, 52 (78 %) displayed the characteristic endoscopic findings of smooth, round, sessile elevations covered with normal-appearing or yellow-discolored mucosa; in 15 (22 %) there were one or more atypical endoscopic findings. These included a semipedunculated appearance (n = 6), hyperemia (n = 5), a central depression (n = 6), erosion (n = 5), and ulceration (n = 4). Atypical findings were noted in none of 20 carcinoids &lambda< 5 mm in diameter; in six (20 %) of the 30 carcinoids between 5 mm and 9 mm; in six (43 %) of the 14 carcinoids between 10 mm and 19 mm; and in three (100 %) of the three carcinoids >/= 20 mm in diameter ( P < 0.001). Invasion into the muscularis propria or metastasis to the liver or lymph nodes occurred in three of the four patients with ulceration, but it was confirmed in only one of the 63 patients without ulceration ( P < 0.001).

CONCLUSIONS

Atypical endoscopic appearances of rectal carcinoids are observed more frequently as the size of the tumor increases and a finding of ulceration may have a prognostic value.

The antioxidant effect of rebamipide on oxygen free radical production by H. pylori-activated human neutrophils: in comparison with N-acetylcysteine, ascorbic acid and glutathione

Helicobacter pylori(H. pylori)-activated neutrophils produce the oxygen-derived free radicals (OFRs) which play an important role in gastric mucosal cell damage. Rebamipide (2-(4-chlorobenzoylamino)-3-[2-(1H)-quinolinon-4-yl] propionic acid) is an antiulcer compound, which protects gastric mucosa against OFR-mediated injury. In order to investigate the effects of rebamipide on OFR production and to compare the antioxidant activity of rebamipide with those of three known antioxidants, N-acetylcysteine (AC), ascorbic acid (Vit C) and glutathione (GSH), the antioxidant activities were determined by luminol-dependent chemiluminescence (ChL) assay and pyrogallol autoxidation assay. The ChL value was markedly elevated immediately after the addition of H. pylori into the medium containing neutrophils. The antioxidant activity of 1.0 mM rebamipide was greater than that of 0.1 mM rebamipide in the luminol-dependent ChL assay, while in the pyrogallol autoxidation assay, the antioxidant activity of 1.0 mM rebamipide was similar to that of 0.1 mM rebamipide. Rebamipide inhibited OFR generation in the pyrogallol autoxidation assay, with the potency being in the order of GSH > Vit C > rebamipide > AC. In the luminol-dependent ChL assay, the antioxidant activity of rebamipide was the greatest among them. These results indicate that rebamipide is a potent antioxidant and scavenges OFRs produced by H. pylori effectively in luminol-dependent ChL assays.

Incomplete pancreas divisum: is it merely a normal anatomic variant without clinical implications?

BACKGROUND AND STUDY AIMS

Incomplete pancreas divisum (PD) has been generally regarded as merely a normal anatomic variant, without clinical implications. This study compares the prevalence, symptom occurrence rate, clinical presentation, and outcomes of endoscopic treatment in patients with incomplete PD and those with complete PD.

PATIENTS AND METHODS

The study population consisted of 56 patients (27 with complete PD and 29 with incomplete PD), identified from 4473 newly performed endoscopic retrograde cholangiopancreatography examinations. Endoscopic treatment (minor papilla sphincterotomy with stents or nasopancreatic drainage tube insertion) was attempted in 25 symptomatic patients with PD, which was suspected to be causing the associated pancreatic diseases: acute recurrent pancreatitis (ARP) (n = 13; five patients with complete PD and eight with incomplete PD); chronic pancreatitis (CP) (n = 10: five patients with complete PD and five with incomplete PD); and pancreatic-type pain (PP) (n = 2; one patient with complete PD and one with incomplete PD). The mean follow-up period was 17 months (range 9 - 49 months).

RESULTS

In 12 of the 27 patients with complete PD--six with ARP, five with CP, and one with PP--it was suspected that PD was the cause of pancreatic disease. Ten of the 11 symptomatic patients with complete PD underwent successful endoscopic treatment (five with endoscopic minor papilla sphincterotomy and stenting, and five with endoscopic minor papilla sphincterotomy and endoscopic nasopancreatic drainage), and seven of these ten patients benefited from the endoscopic treatment. In 14 of the 29 patients with incomplete PD--eight with ARP, five with CP, and one with PP--it was suspected that pancreas divisum was the cause of pancreatic disease. Thirteen of the 14 symptomatic patients with incomplete PD underwent successful endoscopic treatments (six with endoscopic minor papilla sphincterotomy and stenting, and seven with endoscopic minor papilla sphincterotomy and endoscopic nasopancreatic drainage), and eight of these 13 patients experienced clinical improvement.

CONCLUSIONS

The prevalence rate, symptom occurrence rate, clinical presentation, and outcomes of endoscopic treatment were similar in patients with complete PD and incomplete PD. Incomplete PD may therefore have similar clinical implications to those of complete PD.

Risk factors for recurrence of primary bile duct stones after endoscopic biliary sphincterotomy

BACKGROUND

Endoscopic biliary sphincterotomy (EST) is a well-established procedure for bile duct stone extraction. Bile duct stones can be classified as primary or secondary. However, few data are available on the recurrence of primary and secondary bile duct stones after EST. Therefore risk factors for the recurrence of primary bile duct stones after EST were prospectively studied.

METHODS

Between 1991 and 1997, 61 patients underwent EST for primary bile duct stones. All met the following criteria: (1) previous cholecystectomy without bile duct exploration, (2) detection of bile duct stones at least 2 years after initial cholecystectomy. Mean follow-up was 2.2 years. Fourteen patients were lost to follow-up. The recurrence of primary bile duct stones was defined as the detection of bile duct stones no sooner than 6 months after complete clearance of primary bile duct stones.

RESULTS

The overall recurrence rate of primary bile duct stones was 21% (10 of 47). Two significant risk factors for recurrence were identified by multivariate analysis: (1) patients with a bile duct diameter of 13 mm or greater after stone removal had recurrences more frequently than those with a duct diameter of 13 mm or less, and (2) patients whose papilla was located on the inner rim or deep within a diverticulum, so that the papillary orifice was not visible endoscopically, had more frequent recurrences than patients with a papilla outside the diverticulum, or no peripapillary diverticulum.

CONCLUSION

The independent risk factors for recurrence of primary bile duct stones were sustained dilation of the bile duct even after complete removal of stones and location of the papilla on the inner rim or deep within a diverticulum.

Radiologic findings of Behçet syndrome involving the gastrointestinal tract

Behçet syndrome is characterized by the histopathologic finding of nonspecific vasculitis in multiple organs. The diagnosis is usually made on the basis of the combination of clinical signs and symptoms. This disease involves the gastrointestinal tract in 10%-50% of patients, and the terminal ileum and cecum are chiefly affected. Barium study is useful in demonstrating the characteristic radiographic features of Behçet syndrome involving the gastrointestinal tract. The presence of deep, penetrating ulcers results in a high rate of complications, such as perforation, fistula, hemorrhage, and peritonitis. Furthermore, recurrence of disease adjacent to or at the surgical anastomosis is common. Computed tomography is useful in determining the extent of the lesions and in identifying cases in which complications are likely to occur. Familiarity with the various radiologic findings of Behçet syndrome involving the gastrointestinal tract helps in making an early diagnosis, as well as in establishing an appropriate treatment strategy.