RAJIV GANDHI UNIVERSITY OF HEALTH SCIENCES,

BANGALORE, KARNATAKA

ANNEXURE – II

PROFORMA FOR REGISTRATION OF SUBJECTS FOR DISSERTATION

1 / Name of the Candidate and Address (in Block Letters) / DR.GIRISH M .S
S/O SHIVANNA
SIDDAPURA GATE
MADHUGIRI TALUK
TUMKUR DISTRICT. PIN-572132
2 / Name of the Institution / J.J.M. MEDICAL COLLEGE
DAVANGERE–577 004,
KARNATAKA
3 / Course of Study and Subject / POSTGRADUATE DEGREE
M.D. IN GENERAL MEDICINE
4 / Date of Admission to Course / 29th MAY 2013
5 / Title of the Topic / STUDY OF EFFICACY OF POCKET PULSE OXIMETER AND DIGITAL PULSE OXIMETER IN SCREENING ASYMPTOMATIC LOWER EXTREMITY ARTERIAL DISEASE(LEAD) IN TYPE-2 DIABETES MELLITUS
6 / BRIEF RESUME OF THE INTENDED WORK:
6.1  Need for the study:
Lower extremity arterial disease (LEAD) is a significant socio-economic burden to society and causes severe impairment of quality of life in patients affected by it. Hypertension, smoking, diabetes, and dyslipidemia are the major risk factors for LEAD. Prevalence of Lower extremity arterial disease (LEAD) is higher in Diabetes mellitus than in general population. 30-40% of all patients with LEAD have diabetes mellitus and diabetes increases the risk of developing symptomatic LEAD by 2-4 fold1. LEAD is a leading cause of limb amputations in diabetics2.
Clinical presentation of ischaemic limb disease extends over a wide spectrum of intermittent claudication, critical limb ischaemia and gangrene resulting from total peripheral artery occlusion. Limb pain either at rest or on walking is suggestive of occlusive peripheral arterial disease3.
Early detection of LEAD before onset of symptoms in patients with diabetes mellitus is desirable and it can help for better control of mortality and morbidity associated with the disease. But LEAD in general population as well as in diabetics remains underdiagnosed mainly due to lack of simple, noninvasive, easily administrable screening methods.
Although Ankle-Brachial Index (ABI) is considered as standard method for screening of LEAD in practice, but the procedure of measuring same is cumbersome, since it is time consuming, needs a dedicated device and requires technical skills to record it. Moreover some of the earlier studies have showed that, due to calcification of tunica media (Monckeberg sclerosis) seen in diabetics, the arteries become stiff and non-compressible. This gives falsely elevated ABI.4
Therefore there is need for finding new screening methods, which are simple, non-invasive, objective and easily administrable to detect asymptomatic LEAD in type-2 diabetes mellitus.
Pulse oximeters are simple, noninvasive instruments which are used to measure the peripheral blood Sao2. Peripheral blood Sao2 meassurement is one of the methods used by vascular surgeons to assess patency of the arterial reconstructions.
In our present study we intend to study the efficacy of pocket pulse oximeter and digital pulse oximeter as screening tools for detecting asymptomatic LEAD in type-2 diabetes mellitus.
6.2  Review of Literature
1.  J. Ena et al, in their study on 223 patients, with finger-toe Sao2 gradient greater than 2% to detect peripheral arterial disease, reported that, peripheral arterial disease was detected in 47(21%) patients, Pocket Pulse oximeter had sensitivity of 42.6%(95% Confidence Interval (CI), 30.0%-55.3%), specificity of 79.1%(95%CI, 75.7%-82.6%), positive predictive value of 35.7%(95%CI, 25.2%-46.4%), negative predictive value of 83.4%(95%CI, 79.8%-87.1%), positive likelihood ratio2.03(95%CI, 1.23-3.17) and negative likelihood ratio0.73(95%CI, 0.54-0.93) They concluded that Pocket pulse oximeter showed insufficient sensitivity as a screening method for detecting Peripheral arterial diseases in patients with diabetes mellitus4.
2.  Parameswaran G I, and Dolan J, in their study on asymptomatic LEAD patients in type-2 diabetes mellitus compared the accuracy of pulse oximetry and ABI with Doppler waveform analysis for detecting LEAD, found that, among 57 patients(114 extremities) 31% had LEAD, pulse oximeter had sensitivity of 77%(95% confidence interval(CI), 61%-88%), specificity of 97%(95%CI, 91%-99%), positive likelihood ratio was 30(95% CI, 7.6-121) and negative likelihood ratio was 0.23(95% CI, 0.12-0.43) and ABI had sensitivity of 63%(95%CI, 46%-77%), specificity of 97%(95%CI, 91%-99%) positive likelihood ratio was 24.8(95% CI, 6.2-99.8), negative likelihood ratio was 0.38(095% CI, 0.25-0.59). They concluded that pulse oximetry of toes is as accurate as ABI to screen for LEAD in patients with type-2 diabetes mellitus and combination of two tests increases the sensitivity5.
3.  Jung-Nan Kwon, Whan-Bong Lee, in their study on utility of digital pulse oximetry in the screening of peripheral vascular disease (PAD) on 49 patients(98 limbs), found that, digital pulse oximetry showed sensitivity of 87.06%, specificity of 87.8%, positive predictive value of 84.3% and negative predictive value of 90% and ABI had sensitivity of 55.09%, specificity of 94%, positive predictive value of 96.7%, negative predictive value of 39.02%. They concluded that digital pulse oximetry can be useful, non-invasive screening device as well as ABI in peripheral vascular disease6.
4.  Feigelson et al, found that when they excluded patients with symptoms and signs of LEAD, ABI values less than 0.9 had sensitivity of only 28.4%. Therefore concluded that- ABI seems to be less accurate as a screening test in patients without symptoms or signs of LEAD7.
Thus previous studies have shown conflicting results about efficacy of pulse oximeter and ABI as screening tools for detecting LEAD under different clinical settings.
Objectives of the Study:
To assess the efficacy of Pocket pulse oximeter and Digital pulse oximter as screening tools to detect the asymptomatic lower extremity arterial diseases(LEAD) in type-2 diabetes mellitus.
7. / MATERIALS AND METHODS
7.1  Source of Data:
Type-2 diabetes mellitus patients, including both male and female, admitted or treated as out-patients in Bapuji Hospital or in Chigateri Government Hospital (CGH), attached to J.J.M. Medical College, during study period of 1st December 2013 to 31st May 2015, will be included in this study.
7.2  Method of collection of Data (including sampling procedures if any):
Minimum 50 patients, with Type-2 diabetes mellitus, without any symptoms or signs of LEAD, admitted or treated as out-patients in Bapuji hospital or in Chigateri government hospital (CGH), will be studied using random sampling method over a period of one and half years.
A detailed history will be obtained from qualifying patients using a pre-designed, structured proforma. Further, a detailed systemic examination, followed by relevant investigations will be conducted and results will be noted.
Inclusion criteria:
Both male and female patients with Type-2 diabetes mellitus, with age more than or equal to 40 years, who are able to walk, will be considered for enrollment in the study.
Exclusion criteria:
Type-2 diabetes mellitus patients with,
1. Age younger than 40 years.
2. Symptoms or signs of lower extremity arterial disease.
3. Painful inflammatory processes or extreme edema over fingers or toes.
4. Revascularization procedures or amputation in any of the limbs, fingers or toes.
Study design:
It is a cross sectional study.
Data analysis will be done using Doppler waveform analysis of lower extremity arteries to detect LEAD as reference standard, to compare the results of both pulse oximeters. Significant LEAD is defined as presence of monophasic waveforms at anyone of the lower extremity arteries during Doppler waveform analysis.
Qualifying patients will be examined with pocket pulse oximeter and digital pulse oximeter for measuring Sao2 of their index fingers, big toes in the supine position and at 12-inch elevation. Pulse oximetry of the toe will be considered abnormal (indicative of LEAD) if the Sao2 of toe is more than 2% lower from finger value or if there is decrease of Sao2 of toe by more than 2% on 12-inch elevation of lower limb compared to Sao2 of toe in supine position.
Paired t-test and correlation analysis will be used to derive, Sensitivity, Specificity, likelihood ratios for abnormal pulse oximetry.
7.3  Does the Study require any investigations or interventions to be conducted on patients or other humans or animals? If so please describe briefly.
Yes
Following investigations are required to be done on patients qualifying for the study.They are
FBS,
PPBS,
Blood urea,
Serum creatinine,
Lipid Profile,
Pulse oximetry of fingers and toes,
Doppler waveform analysis of lower extremity arteries.
7.4  Has ethical clearance been obtained from your institution in case of 7.3?
Yes
Approval from ethical committee of J.J.M.Medical college, Davangere has been taken.
8. / LIST OF REFERENCES:
1.  Marso SP and William R.Hiatt, peripheral arterial disease in patients with diabetes. Journal of American college of cardiology 2006;47(5):921-929
2.  Global Lower Extremity Amputation Study Group(2002). Epidemiology of lower extremity amputation in centers in Europe, North America and East Asia. British Journal of Surgery 2000;87:328-337.
3.  Muralidhar S Rao, Macrovascular complications of diabetes. In: YP Munjal, SK Sharma, editors, API Text book of medicine, 9th edition, volume-1:370-371
4.  Javier Ena, Carlos R.Argente, Victor Gonzalez-Sanchez, Natividad Algado, Gema Verdu, Teresa Lozano,Use of pocket pulse oximeter for detecting peripheral arterial disease in patients with diabetes mellitus. Journal of Diabetes Mellitus(2013);3(2):79-85.
5.  Parameswaran GI, Brand K, Dolan J, Pulse oximetry as a potential screening tool for lower extremity arterial diseases in asymptomatic patients with diabetes mellitus. Journal of Archives of Internal Medicine 2005 FEB 28:165(4):442-446
6.  Jung-Nam Kwon, Whan-Bong Lee, Utility of digital pulse oximetry in the screening of lower extremity arterial disease. Journal of the Korean Surgical Society 2012 February; 82(2);94-100.
7.  Feigelson HS, Criqui MH, Fronek A, Langer RD, Molgaard CA, Screening for peripheral arterial disease: the sensitivity, specificity and predictive value of noninvasive tests in a defined population. American journal of Epidemiology 1994;140:526-534.
8.  Ailvin C. Powers,Chapter 344:Diabetes Mellitus. In: Harrison’s Principles of Internal Medicine,18th edition,volume-2, The McGraw-Hill companies, Inc. United States of America 2012:2968-3003
9. / Signature of the Candidate
10. / Remarks of the Guide / Inetnded study is good, relevant, both by specificity and sensitivity correlating to Doppler study with digital pulse oximeter and pocket pulse oximeter
11. / Name & Designation(in block letters)
11.1  Guide
11.2  Signature
11.3  Co-Guide (If any)
11.4  Signature
11.5  Head of the Department
11.6  Signature / Dr. P.E.DHANANJAYA MD
PROFESSOR,
DEPT OF GENERAL MEDICINE,
J.J.M MEDICAL COLLEGE,
DAVANGERE-577004
Dr. S.N.VISHWAKUMAR MD
PROFESSOR AND HEAD,
DEPT OF GENERAL MEDICINE,
J.J.M.MEDICAL COLLEGE,
DAVANGERE-577004
12 / 12.1  Remarks of the Chairman & the Principal
12.2 Signature