Evaluation of initial shockable rhythm as an indicator of short no-flow time in cardiac arrest: a national registry study

2022 ◽  
pp. emermed-2021-211823
Author(s):  
Keita Shibahashi ◽  
Kazuhiro Sugiyama ◽  
Takuto Ishida ◽  
Yuichi Hamabe

BackgroundThe duration from collapse to initiation of cardiopulmonary resuscitation (no-flow time) is one of the most important determinants of outcomes after out-of-hospital cardiac arrest (OHCA). Initial shockable cardiac rhythm (ventricular fibrillation or ventricular tachycardia) is reported to be a marker of short no-flow time; however, there is conflicting evidence regarding the impact of initial shockable cardiac rhythm on treatment decisions. We investigated the association between initial shockable cardiac rhythm and the no-flow time and evaluated whether initial shockable cardiac rhythm can be a marker of short no-flow time in patients with OHCA.MethodsPatients aged 18 years and older experiencing OHCA between 2010 and 2016 were selected from a nationwide population-based Japanese database. The association between the no-flow time duration and initial shockable cardiac rhythm was evaluated. Diagnostic accuracy was evaluated using the sensitivity, specificity and positive predictive value.ResultsA total of 177 634 patients were eligible for the analysis. The median age was 77 years (58.3%, men). Initial shockable cardiac rhythm was recorded in 11.8% of the patients. No-flow time duration was significantly associated with lower probability of initial shockable cardiac rhythm, with an adjusted OR of 0.97 (95% CI 0.96 to 0.97) per additional minute. The sensitivity, specificity and positive predictive value of initial shockable cardiac rhythm to identify a no-flow time of <5 min were 0.12 (95% CI 0.12 to 0.12), 0.88 (95% CI 0.88 to 0.89) and 0.35 (95% CI 0.34 to 0.35), respectively. The positive predictive values were 0.90, 0.95 and 0.99 with no-flow times of 15, 18 and 28 min, respectively.ConclusionsAlthough there was a significant association between initial shockable cardiac rhythm and no-flow time duration, initial shockable cardiac rhythm was not reliable when solely used as a surrogate of a short no-flow time duration after OHCA.

Medicina ◽  
2021 ◽  
Vol 57 (5) ◽  
pp. 503
Author(s):  
Thomas F. Monaghan ◽  
Syed N. Rahman ◽  
Christina W. Agudelo ◽  
Alan J. Wein ◽  
Jason M. Lazar ◽  
...  

Sensitivity, which denotes the proportion of subjects correctly given a positive assignment out of all subjects who are actually positive for the outcome, indicates how well a test can classify subjects who truly have the outcome of interest. Specificity, which denotes the proportion of subjects correctly given a negative assignment out of all subjects who are actually negative for the outcome, indicates how well a test can classify subjects who truly do not have the outcome of interest. Positive predictive value reflects the proportion of subjects with a positive test result who truly have the outcome of interest. Negative predictive value reflects the proportion of subjects with a negative test result who truly do not have the outcome of interest. Sensitivity and specificity are inversely related, wherein one increases as the other decreases, but are generally considered stable for a given test, whereas positive and negative predictive values do inherently vary with pre-test probability (e.g., changes in population disease prevalence). This article will further detail the concepts of sensitivity, specificity, and predictive values using a recent real-world example from the medical literature.


2019 ◽  
Vol 2019 ◽  
pp. 1-7 ◽  
Author(s):  
Konuralp Yakar

Aim. To compare the clinical performance of the Spot Vision Screener used to detect amblyopia risk factors (ARFs) in children before and after induction of cycloplegia; the children were referred because they met the screening criteria of the American Association for Pediatric Ophthalmology and Strabismus (AAPOS). Methods. The Spot Vision Screener and a standard autorefractometer were used to examine 200 eyes of 100 children aged 3–10 years, before and after cycloplegia induction, in terms of ARFs. Sensitivity, specificity, and positive and negative predictive values for the detection of significant refractive errors were measured using the AAPOS referral criteria. It was explored that Spot Screener data were affected by cycloplegia. The extent of agreement between cycloplegic/noncycloplegic photoscreening data and cycloplegic autorefraction measurements was assessed using Wilcoxon and Spearman correlation analyses. Results. The Spot’s sensitivity was improved from 60.9% to 85.3% and specificity from 94.9% to 87.4% with cycloplegia compared to cycloplegic standard autorefractometer results. The positive predictive value of Spot was 75.7%, and the negative predictive value was 90.4% without cycloplegia. With cycloplegia, the positive predictive value of Spot was 63.6% and the negative predictive value was 95.8%. Conclusions. The Spot Screener afforded moderate sensitivity and high specificity prior to cycloplegia. The sensitivity and negative predictive value improved after induction of cycloplegia. Examiners should be aware of the effects of cycloplegia on their findings.


2020 ◽  
Vol 15 (04) ◽  
pp. 75-79
Author(s):  
Agnus Mathew ◽  
DM Patel ◽  
KK Hadiya

This study was carried out on 10 infertile barren mares to evaluate the sensitivity, specificity, predictive values and agreement (kappa value) of cytological and microbiological findings of three diagnosing techniques of endometritis, viz., endometrial biopsy (EB), cytobrush (CB) and low volume uterine lavage (LVL) in relation to endometrial histology. When histological examinations from EB were used as “the best standard,” the sensitivity of cytology from EB, CB and LVL technique was 0.33, 0.50 and 0.50; specificity 0.75, 1.00 and 0.75; positive predictive value 0.66, 1.00 and 0.75, and negative predictive value was 0.42, 0.57 and 0.50, respectively. The sensitivity of bacteriology from EB, CB and LVL technique was 0.83, 0.83 and 1.00; the specificity was 0.75, 0.75 and 0.50; positive predictive value 0.83, 0.83 and 0.75, and the negative predictive value was 0.75, 0.75 and 1.00, respectively. In all the cases, the sensitivity of the bacteriology was found to be higher than the sensitivity of cytology. When the results of cytological and bacteriological examinations were combined, no any increase in the sensitivity was found. Bacteriology and cytology from CB showed the highest positive predictive value demonstrating that a positive result is an accurate indication of endometritis. Sensitivity values were always higher if smears were evaluated according to PMNs to epithelial cell ratio, and the highest values were observed in specimens collected from CB and LVL. The evaluation of cytological smears based on counting PMNs in relation to epithelial cells was a better method for diagnosis of endometritis than counting the number of PMNs per high power microscopic field (k value 0.07-0.47 vs. 0.00). The agreement of the diagnosis of endometritis between the three techniques of the collection was from fair to poor and between the different criteria adopted to evaluate smears was always poor. However, the agreement of the diagnosis of endometritis by the microbial culture was moderate between the three techniques of the collection (k value 0.55-0.58).


2021 ◽  
Vol 108 (Supplement_7) ◽  
Author(s):  
Nixon Phua Cher Yang ◽  
Muhammad Adeel Javed Butt ◽  
Parmvir Singh Nijjar ◽  
Saung Phyu ◽  
Musa Barkeji

Abstract Aims Nipple discharge is a presentation commonly seen at breast clinics. It is conventionally evaluated with physical examination and sonography( or mammography). The aim of this study is to investigate the diagnostic value of magnetic resonance imaging (MRI) as an additional imaging tool in the evaluation of potential malignancy in patients presented with nipple discharge. Methods A retrospective evaluation of 85 patients with nipple discharge who underwent breast ultrasound (USS) and MRI between 04/06/2008 and 25/10/2019 was conducted. Clinical notes, radiographic reports and biopsy results were reviewed. Sensitivity, specificity, positive predictive value and negative predictive value of USS and MRI were calculated. Results Out of the 85 patients (all female; mean age 45.33 +/- 12.93 years old) with nipple discharge, 11 were found to have biopsy-proven malignancy (invasive ductal carcinoma/ ductal carcinoma in situ; 12.94% risk). USS failed to identify seven malignancies (27.27% sensitivity) while MRI missed three malignancies (72.72% sensitivity). USS falsely identified four malignancies from 74 patients with no malignancy (94.59% specificity) while MRI only falsely identified one case (98.65% specificity). For patients with negative USS results (U1/U2/U3) or negative MRI results (BI-RADS category 1,2 or 3), the negative predictive values of USS is 89.74% while that of MRI is 96.05%. The positive predictive values of USS and MRI are 42.86% and 88.88% respectively. Conclusion Compared to USS, MRI has a higher sensitivity, specificity, positive predictive value and predictive value. It will be a valuable addition to the standard nipple discharge evaluation workup to help rule out malignancy.


2018 ◽  
Vol 5 (3) ◽  
pp. 796
Author(s):  
Vamsavardhan Pasumarthi ◽  
C. P. Madhu

Background: The RIPASA Score is a new diagnostic scoring system developed for the diagnosis of Acute Appendicitis which showed higher sensitivity, specificity and diagnostic accuracy compared to ALVARADO Score, particularly when applied to Asian population. Not many studies have been conducted to compare RIPASA and ALVARADO scoring systems. Hence, author want to compare prospectively Alvarado and RIPASA score by applying them to the patients attending the hospital with right iliac fossa pain that could probably be acute appendicitis.Methods: A prospective analysis of 116 cases admitted with RIF pain during a 2 years period was performed. Patients between 15-60 years were scored as per Alvarado and RIPASA scoring system. Histopathological reports of the cases were collected and compared with the scores. ROC curve area analysis was performed to examine diagnostic accuracy of RIPASA and ALVARADO scores.Results: The sensitivity of ALVARADO score is estimated to be 52.08 for a cut off of 6. The specificity is 80%, positive predictive value is 92.59, negative predictive value is 25.81. The Diagnostic accuracy of ALVARADO scoring is found to be 56.9. The sensitivity, specificity, positive predictive value and negative predictive values of RIPASA scoring system are 75%, 65%, 91.14%, 35.14%. The diagnostic accuracy of RIPASA score is 73.28.Conclusions: The difference in the diagnostic accuracy between ALVARADO and RIPASA scoring system is significant indicating that the RIPASA score is a much better diagnostic tool for the diagnosis of acute appendicitis. When the ROC curve was observed the area under the curve is high for RIPASA scoring system.


2020 ◽  
Vol 14 (2) ◽  
pp. 97-102
Author(s):  
Khalid Rehman `Yousaf ◽  
Shahzad Saeed ◽  
Saman Chaudhry ◽  
Rabia Bashrat ◽  
Abadullah Khalid ◽  
...  

Background: Ovarian torsion diagnosis is a great challenge as delay in diagnosis can cause severe morbidity. Early accurate diagnosis is crucial to preserve ovarian function. Ultrasonography being the primary imaging modality plays a vital role in the evaluation of suspected ovarian torsion by helping surgeons reach the correct diagnosis, thus avoiding unnecessary intervention. This study aims to determine the diagnostic accuracy of isolated and combined sonographic features of ovarian torsion on grey scale and Doppler transvaginal ultrasonography. Patients and methods: From radiology database, from January 2016 till December 2019, sonographic signs of ovarian torsion in 113 women with suspected ovarian torsion on ultrasonography and subsequent surgical diagnosis were evaluated. Ultrasound findings were compared with surgical findings to determine the accuracy, sensitivity, specificity, and positive and negative predictive values of individual and combined ultrasound signs. Results: Diagnostic accuracy of ultrasound for ovarian torsion was 85.8%. Abnormal ovarian Doppler flow was the most accurate individual sonographic sign with accuracy, sensitivity, specificity and positive predictive value of 85.8%, 83.5%, 100% and 100% respectively followed by ovarian enlargement and ovarian edema. Combined ultrasound signs resulted in higher sensitivity and positive predictive values, and lower specificity and negative predictive values for ovarian torsion. Increasing the number of sonographic parameters increased the specificity but decreased sensitivity. High accuracy, sensitivity, positive predictive value, specificity and negative predictive value was seen when combination of three or two sonographic parameters was used as diagnostic criteria. Conclusion: Transvaginal sonography is a convenient, reliable and extremely useful imaging modality for preoperative diagnosis of ovarian torsion with high specificity, sensitivity, positive predictive value and diagnostic accuracy helping treating physicians to take prompt decisions regarding timely surgical intervention. However, due to low negative predictive values, absence of sonographic signs does not rule out ovarian torsion and high index of clinical suspicion remains of utmost importance.


2014 ◽  
Vol 74 (1) ◽  
pp. 14-18 ◽  
Author(s):  
Mollie N Carruthers ◽  
Arezou Khosroshahi ◽  
Tamara Augustin ◽  
Vikram Deshpande ◽  
John H Stone

ObjectivesWe evaluated the sensitivity, specificity and positive and negative predictive values of elevated serum IgG4 concentrations for the diagnosis of IgG4-RD.MethodsBetween 2001 and 2011, 190 unique patients had elevated serum IgG4 measurements. We reviewed electronic medical records to determine the indication for IgG4 measurement and underlying clinical diagnosis. Additionally, we reviewed the records of 190 other randomly selected patients from a pool of 3360 with normal results, to evaluate test characteristics of the IgG4 measurement.ResultsAmong 380 patients analysed, 72 had either probable or definite IgG4-RD. Sixty-five of the 72 IgG4-RD patients had elevated serum IgG4 concentrations (mean: 405 mg/dL; range 140–2000 mg/dL), for a sensitivity of 90%. Among the 308 subjects without IgG4-RD, 125 had elevated IgG4 (mean: 234 mg/dL; range 135–1180 mg/dL) and 183 had normal IgG4 concentrations, for a specificity of 60%. The negative predictive value of a serum IgG4 assay was 96%, but the positive predictive value only 34%. Analysis of the serum IgG4/total IgG ratio did not improve these test characteristics. Doubling the cutoff for IgG4 improved specificity (91%) but decreased sensitivity to 35%.DiscussionMultiple non-IgG4-RD conditions are associated with elevated serum IgG4, leading to poor specificity and low positive predictive value for this test. A substantial subset of patients with biopsy-proven IgG4-RD do not have elevated serum IgG4. Neither doubling the cutoff for serum IgG4 nor examining the serum IgG4/IgG ratio improves the overall test characteristics for the diagnosis of IgG4-RD.


2018 ◽  
Vol 48 (1) ◽  
pp. 38-42 ◽  
Author(s):  
Jakob Kleif ◽  
Lau C. Thygesen ◽  
Ismail Gögenur

Aims: Appendicitis is a common disease. The nationwide Danish National Patient Register provides an important data source for epidemiological research. Data used in register-based epidemiological research needs to be validated. We aimed to validate the diagnosis of appendicitis in the Danish National Patient Register. Methods: From 1997 to 2015 nationwide data from the Danish National Patient Register, the Danish Pathology Register, and the Danish Civil Registration System were used to validate the diagnosis of appendicitis or the combination of the diagnosis for appendicitis and surgical removal of the appendix in the Danish National Patient Register. Sensitivity, specificity, and positive and negative predictive values were calculated using pathology reports as golden standard. Results: Diagnosis of appendicitis in the Danish National Patient Register had a sensitivity, specificity, positive predictive value, and negative predictive value of 0.928 (95% confidence interval (CI): 0.927; 0.930), 0.995 (95% CI: 0.995; 0.995), 0.769 (95% CI: 0.767; 0.771), and 0.999 (95% CI: 0.999; 0.999). A diagnosis of appendicitis and a procedure code for surgical removal of the appendix had a sensitivity, specificity, positive predictive value, and negative predictive value of 0.886 (95% CI: 0.885; 0.888), 0.998 (95% CI: 0.998; 0.998), 0.895 (95% CI: 0.894; 0.897), and 0.998 (95% CI: 0.998; 0.998). Conclusions: The diagnosis of appendicitis alone or in combination with the registered surgical removal of the appendix in the Danish National Patient Register showed acceptable validity. Whether to use the diagnosis for appendicitis only or in combination with procedure codes for the removal of the appendix depends on whether high sensitivity or high positive predictive values are warranted.


2020 ◽  
Vol 9 (3) ◽  
pp. 190-194
Author(s):  
Naureen Saeed ◽  
Fatima-tuz-zuhra ◽  
Nadeem Ikram ◽  
Farhana Shaukat ◽  
Fareeha Sardar

Background: Pakistan faces an immense burden of pulmonary tuberculosis (TB) due to large number of cases and limited resources. Despite the recent advancement in the diagnostic techniques for pulmonary TB, smear microscopy is still a useful technique for the diagnosis of this disease. This study was conducted in order to compare the diagnostic value of Auramine stain with the conventional Ziehl-Neelsen (ZN) stain on the sputum smear for the diagnosis of pulmonary TB, keeping GeneXpert MTB/RIF as the gold standard. Method: This cross-sectional study was conducted on 356 suspected patients of pulmonary TB referred to the Pathology laboratory from TB ward and OPD of District Head Quarter (DHQ) teaching hospital Rawalpindi, Pakistan. Sputum specimen were collected and two smears were prepared from each sputum sample on which Auramine phenol and Ziehl-Neelsen staining were carried out as per WHO recommendations. All these samples were further tested using Gene Xpert MTB/RIF technique. The sensitivity, specificity, Positive predictive value (PPV) and Negative predictive values (NPV) of ZN and Auramine stain were calculated and compared with GeneXpert MTB/RIF technique. Results: Out of the total 356 samples, 64(18%) were positive and 291(82%) were negative by GeneXpert which was taken as the gold standard. On comparison with GeneXpert, percentage of true positive was greater in case of Auramine than ZN stained samples (16.29% versus 12.92%), while the percentage of false positive was same for both staining techniques (0.28%). There were lesser false negative cases observed in samples stained by Auramine as compared to the ones stained by ZN (1.68% versus 5.05%). The sensitivity, specificity, positive predictive value and negative predictive values were 97.87%, 94.17%, 71.88 and 99.66%, respectively for the ZN staining and 98.31%, 97.98%, 90.63% and 99.66% respectively, for the Auramine phenol staining. Conclusion: Smear microscopy using Auramine phenol stain is a useful technique for the diagnosis of pulmonary TB. The Auramine phenol staining with fluorescent microscopy is found to be superior to ZN staining because of higher sensitivity and specificity. Keywords: Auramine phenol, Fluorescence microscopy, GeneXpert, Mycobacterium tuberculosis, Ziehl-Neelsen


2017 ◽  
Vol 35 (1) ◽  
pp. 95-103 ◽  
Author(s):  
Sergio Serrano-Gomez ◽  
Gabriel Burgos-Angulo ◽  
Daniela Camila Niño-Vargas ◽  
María Eugenia Niño ◽  
María Eugenia Cárdenas ◽  
...  

Purpose: Over 170 biomarkers are being investigated regarding their prognostic and diagnostic accuracy in sepsis in order to find new tools to reduce morbidity and mortality. Matrix metalloproteinases (MMPs) and their inhibitors have been recently studied as promising new prognostic biomarkers in patients with sepsis. This study is aimed at determining the utility of several cutoff points of these biomarkers to predict mortality in patients with sepsis. Materials and Methods: A multicenter, prospective, analytic cohort study was performed in the metropolitan area of Bucaramanga, Colombia. A total of 289 patients with sepsis and septic shock were included. MMP-9, MMP-2, tissue inhibitor of metalloproteinase 1 (TIMP-1), TIMP-2, TIMP-1/MMP-9 ratio, and TIMP-2/MMP-2 ratio were determined in blood samples. Value ranges were correlated with mortality to estimate sensitivity, specificity, positive predictive value, negative predictive value, and area under the receiving operating characteristic curve. Results: Sensitivity ranged from 33.3% (MMP-9/TIMP-1 ratio) to 60.6% (TIMP-1) and specificity varied from 38.8% (MMP-2/TIMP-2 ratio) to 58.5% (TIMP-1). As for predictive values, positive predictive value range was from 17.5% (MMP-9/TIMP-1 ratio) to 70.4% (MMP-2/TIMP-2 ratio), whereas negative predictive values were between 23.2% (MMP-2/TIMP-2 ratio) and 80.9% (TIMP-1). Finally, area under the curve scores ranged from 0.31 (MMP-9/TIMP-1 ratio) to 0.623 (TIMP-1). Conclusion: Although TIMP-1 showed higher sensitivity, specificity, and negative predictive value, with a representative population sample, we conclude that none of the evaluated biomarkers had significant predictive value for mortality.


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