Comorbidity was a
presence of one or more additional medical conditions or diseases diagnosed by
physicians. Day of symptom onset was the day when the initial symptom began
such as runny nose, muscle ache, cough, sore throat, dyspnoea, etc. Based on
WHO severity score, the severity of COVID-19 was classified as mild, moderate,
severe disease and critical disease. Mild disease was symptomatic patients
without evidence of viral pneumonia in CXR or hypoxia. Moderate disease was
confirmed patients with clinical signs of pneumonia (fever, cough, dyspnoea,
and fast breathing), CXR showed pneumonia and SaO2 on air is ? 95%. Severe
disease was confirmed patient with clinical signs of pneumonia (fever, cough,
dyspnoea, and fast breathing) adding one of the following: respiratory rate
> 30 breaths per min, severe respiratory distress and SpO2 < 90% on room
air. Critical disease was confirmed COVID-19 patient with one or more of the
followings: ARDS, sepsis, septic shock and acute thrombosis (pulmonary
embolism, acute coronary syndrome, and acute stroke). Total antibody titer was
defined as adequate if the total antibody level was ? 1:32 COI; already set
criteria for donor total antibody level for convalescent plasma donation. The
hospital outcome at the time of discharge from hospital (survival status) was
either survivor or non-survivor. The discharge criteria were determined by
attending physician. Timing of plasma therapy was “early” if patient obtained
CPT or Standard treatment less than 7 days after symptom onset, and “late” if
patient obtained CPT or Standard treatment more than 7 days after symptom
onset. Early therapy group was those who received CPT or Standard treatment
less than 7 days after symptom onset and late therapy group was those who
received CPT or Standard treatment more than 7 days after symptom onset.
Comorbid status was presence of one or more comorbid diseases like diabetes
mellitus, hypertension, chronic kidney disease (eGFR > 30 ml/min), chronic
obstructive airway disease, bronchial asthma, stroke, chronic liver disease.
The comorbid associated group was having one or more comorbid disease and
comorbid non-associated group did not have comorbid disease. Immune status was
defined as normal or immune compromised. Immuno compromised status was those
not having one of immune compromised state transplant recipients, those on oral
steroids for more than two weeks, those on immune suppressants, systematic
lupus erythematous, diabetes mellitus, ESRD (eGFR < 30 ml/min), and,
haematological malignancy, The primary outcome was survival status; survive or
non-survive. Normal immune status was those not having immune compromised
state. Secondary outcome was duration of hospital stays, and the requirement
for oxygen therapy (increased, same or decreased). Timing/duration of symptoms
onset to admission (days) was time from first symptom to arrival at hospital.
Duration of hospital stay was total duration of hospital stay till discharge
either in survival state or non-survival state which may be beyond secondary
outcome i.e., 28 days. Severity of lung parenchyma involvement in CXR was
calculated by Brixia Score as “0 to 18”. Lungs were divided into six zones on a
postero-anterior (PA) or antero-posterior (AP) projection. In the second step,
a score (0 to 3) is assigned to each zone based on lung abnormalities as
follows: (1) “0” if there was no lung abnormalities; (2) “1” if there was
interstitial infiltrates; (3) “2” if there was interstitial and alveolar
infiltrates with interstitial predominance; and, (4) “3” if there was
interstitial and alveolar infiltrates with alveolar predominance. Finally, the
scores of the six lung zones are then added to obtain an overall CXR score
ranging from 0 to 18. Based on WHO severity score, the clinical severity of
COVID?19 infection was classified into four types: mild, moderate, severe and
critical. In mild category, patients have symptoms only, CXR is normal and,
SaO2 on air is normal. In moderate category, CXR shows pneumonias and SaO2 on
air is ? 90%. In severe category, respiratory rate is > 30/min and, SaO2 on
air is < 90%. In critical disease category, the patient has ARDS; he may
have sepsis with multi-organ dysfunction or septic shock or acute thrombosis
(pulmonary embolism, acute coronary syndrome, acute stroke). Absolute
lymphocyte count was low if it was less than 1.0 x 10 9 /L. The level of AST
was raised if it was more than 37 IU/L; the level of ALT was raised if it was
more than 40 IU/L. The level of ferritin was defined as elevated when it was
higher than 400 ng/mL (30 - 400 ng/ml). The level of LDH was defined as
elevated when it was higher than 225 U/l (135 - 225 U/l).The level of D dimer
was defined as elevated when it was higher than 0.5 ?g/ml (< 0.5 ?g/ml).
CRP, an acute?phase reactant reflecting the inflammatory activity, was defined
as elevated when it was higher than 0.5?mg/dl (< 0.5 mg/dl).The most recent
ferritin, LDH and D dimer and CRP values before CPT or Standard treatment
administration was selected as the value of before therapy and the changes of
the value after administration was observed for till discharge/ death (24 hour,
72 hour, 1 week, 2 week, 3 week and 4 week).
Data collection and procedure
Potential donor
candidates who had PCR confirmed COVID-19 infection in the past 6 weeks were
recruited first. Then, their SARS-CoV-2 total antibody was measured with the
use of E411 Fully Automated Immuno Analyzer. Total antibody titer was defined
as adequate if the total antibody level was ? 1:32 COI; it was the already set selection
criteria for convalescent plasma therapy. The plasma from donor having adequate
antibody level was taken with the use of plasma separator- apheresis machine;
they were collected in special plasma packet. The name of the plasma donor and
his antibody level were recorded together with blood group- ABO and Rh. Then,
they were kept in blood bank. One packet of plasma had 200 cc volume. Prior to
transfusion, the total antibody level in the plasma packet was checked again
and noted. Demographic characteristics- sex, age, height, weight, comorbidity
(hypertension, diabetes mellitus), immune status, and timing of CPT or Standard
treatment from symptom onset were collected using a standardized case report
form. Patients with confirmed positive results for nasopharyngeal swab PCR were
initially screened for severity of disease according to WHO severity criteria:
mild, moderate, severe and critical; those patients with severe and critical
disease were selected for initial enrolment. They all received Standard treatment
which included remdesivir, dexamethasone, antibiotics, and low molecular weight
heparin and oxygen therapy. Some of them were given CPT if there was available
matched ABO/Rh plasma, and, the patients himself/close relatives agreed for
CPT. For both CPT group and Standard treatment group, remdesivir injection was
contraindicated in the following situation: (1) hyper-transaminesemia
(aspartate aminotransferase [AST] or alanine aminotransferase [ALT] more than
five times upper limit of normal), (2) estimated glomerular filtration rate
(eGFR) < 30 ml/min, (3) pregnancy, (4) lactation, and (5) allergy to
remdesivir. The study was approved by “Hospital Research and Ethics Committee”
from No. (1) Defence Services General Hospital (1000-Bedded), Mingaladon, Yangon.
After getting the informed consent for CPT, blood for grouping and matching was
done. One packet of matched plasma was given under supervision of physician.
Side effects were monitored and treated accordingly. Timing of CPT in relation
to symptom onset was recorded too. The patients were followed up till discharge
or death. Patient data were stratified by age, sex, body weight, co-morbidity,
immune compromised state, timing of CPT or Standard treatment. Data were
collected by using standardized forms and analysis was done. All the data were
recorded in proforma. The data were checked by two medical officers and then,
supervision, completeness, and consistency of collected data were performed by
the principle investigator. The primary outcome was survival status; survive or
non-survive. The secondary outcome was duration of hospital stays, the
requirement for oxygen therapy (increased, same or decreased), the requirement
for ventilatory support (required or not), and changes in chest radiograph
(improved, same or worse) on Day 7 after therapy. The blood levels of
inflammatory markers (ferritin, LDH, D-dimer and CRP), complete picture, liver
enzymes, serum creatinine and sugar were done before and after CPT (24 hour, 72
hour, 1 week, 2 week, 3 week and 4 week). The most recent ferritin, LDH and D
dimer, CRP, complete picture, liver enzymes, serum creatinine and sugar values
before CPT or Standard treatment administration was selected as the value of
before therapy and the changes of the value after treatment was observed till
discharge/death (24 hour, 72 hour, 1 week, 2 week, 3 week and 4 week). The
clinical outcome of the patients was evaluated daily till 4 week after
treatment. Both clinical, radiological and laboratory data were collected in
standardized preform and confidentiality was maintained. The data were checked
by two medical officers and then, supervision, completeness, and consistency of
collected data were performed by the principle investigator.
Sample
size calculation
The output of the sample
size calculation for an equivalence trial with continuous outcome
Standard deviation (?)
= 0.80
Mean difference between
2 groups (?) = 0.20
Margin (?) = 0.50
Ratio between 2 groups
(k) = 1.0
Alpha (?) = 0.05, Z
(0.950) = 1.644854
Beta (?) = 0.20, Z (0.900) = 1.281552
Sample size: n1 = 122,
n2 = 122
