Rates Among Hospitalized Patients With COVID-19 Treated With Convalescent Plasma: A Systematic Review and Meta-Analysis

Objective

To examine the association of COVID-19 convalescent plasma transfusion with mortality and the differences between subgroups in hospitalized patients with COVID-19.

Patients and Methods

On October 26, 2022, a systematic search was performed for clinical studies of COVID-19 convalescent plasma in the literature from January 1, 2020, to October 26, 2022. Randomized clinical trials and matched cohort studies investigating COVID-19 convalescent plasma transfusion compared with standard of care treatment or placebo among hospitalized patients with confirmed COVID-19 were included. The electronic search yielded 3841 unique records, of which 744 were considered for full-text screening. The selection process was performed independently by a panel of 5 reviewers. The study followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Data were extracted by 5 independent reviewers in duplicate and pooled using an inverse-variance random effects model. The prespecified end point was all-cause mortality during hospitalization.

Results

Thirty-nine randomized clinical trials enrolling 21,529 participants and 70 matched cohort studies enrolling 50,160 participants were included in the systematic review. Separate meta-analyses reported that transfusion of COVID-19 convalescent plasma was associated with a decrease in mortality compared with the control cohort for both randomized clinical trials (odds ratio [OR], 0.87; 95% CI, 0.76-1.00) and matched cohort studies (OR, 0.76; 95% CI, 0.66-0.88). The meta-analysis of subgroups revealed 2 important findings. First, treatment with convalescent plasma containing high antibody levels was associated with a decrease in mortality compared with convalescent plasma containing low antibody levels (OR, 0.85; 95% CI, 0.73 to 0.99). Second, earlier treatment with COVID-19 convalescent plasma was associated with a decrease in mortality compared with the later treatment cohort (OR, 0.63; 95% CI, 0.48 to 0.82).

Conclusion

During COVID-19 convalescent plasma use was associated with a 13% reduced risk of mortality, implying a mortality benefit for hospitalized patients with COVID-19, particularly those treated with convalescent plasma containing high antibody levels treated earlier in the disease course.

Rapid-onset vasodilator responses to exercise in humans: Effect of increased baseline blood flow

NEW FINDINGS

What is the central question of this study? What is the effect of an elevated baseline blood flow, induced by high-dose intra-arterial infusion of either adenosine or ATP, on the rapid-onset vasodilatory response to a single forearm muscle contraction? What is the main finding and its importance? The peak response to a single contraction is unaffected by augmented baseline blood flow, and thus, is likely to be attributable to a feedforward vasodilatory mechanism.

ABSTRACT

The hyperaemic responses to single muscle contractions are proportional to exercise intensity, which, in turn, is proportional to tissue metabolic demand. Hence, we tested the hypothesis that the rapid-onset vasodilatory response after a single muscle contraction would be unaffected when baseline blood flow was increased via high-dose intra-arterial infusion of either adenosine (ADO) or ATP. Twenty-four healthy young participants (28 ± 1 years) performed a single forearm contraction (20% maximal voluntary contraction) 75 min after commencement of a continuous infusion of ADO (n = 6), ATP (n = 8) or saline (control; n = 10). Brachial artery diameter and blood velocity were measured using Doppler ultrasound. Resting forearm vascular conductance (FVC; in millilitres per minute per 100 mmHg per decilitre of forearm volume) was significantly higher during ADO (33 ± 17) and ATP infusion (33 ± 17) compared with the control infusion (8 ± 3; P < 0.05). The peak FVCs post-contraction during ADO and ATP infusions were significantly greater than during the control infusion (P < 0.05), but not different from one another. The peak change in FVC from baseline was similar in all three conditions (control, 14 ± 1; ADO, 24 ± 2; and ATP, 23 ± 6; P = 0.15). Total FVC (area under the curve) did not differ significantly between ADO and ATP (333 ± 69 and 440 ± 125); however, total FVC during ATP infusion was significantly greater compared with the control value (150 ± 19; P < 0.05). We conclude that the peak response to a single contraction is unaffected by augmented baseline blood flow and is therefore likely to be attributable to a feedforward vasodilatory mechanism.

Trends in oral surgery in England and Wales 1991-2000

OBJECTIVE

To investigate trends in oral surgery in England and Wales 1991-2000.

METHODS

Oral surgery procedure data were derived from Dental Practice Board and Department of Health Hospital Episode Statistics.

RESULTS

There was a 6% increase in minor oral surgery (MOS) procedures, including ordinary extractions, extractions of special difficulty, apicectomies and third molar removals, carried out in the General Dental Services (GDS) but the number of third molars removed fell by 32% after 1997. General anaesthetics (GA) administered in the GDS fell by 77% and the number of sedations rose 54% after 1998. There was concentration of minor oral surgery in practices: in the year 2000, 88% of practitioners carried out less than five third molar removals. In the Hospital Dental Service (HDS) there was a 98% increase in day surgery, and a 53% decrease in ordinary admissions for minor oral surgery. HDS waiting times remained constant over the ten year period.

CONCLUSIONS

The principal trends were substantial decreases in apicectomies, third molar removals after 1997 and GAs after 1998; increases in extractions of special difficulty and concentration of MOS in the GODS. Numbers of ordinary extractions did not change. In the HDS there was a large shift from in-patient to daycase provision which has facilitated expansion of maxillofacial surgery. This is an important example of NHS reconfiguration. Perhaps the most important implication of these changes concerns the place of MOS in vocational training.

Plasma creatine kinase responses of 18- to 30-yr-old African-American men to eccentric exercise

PURPOSE

The primary aim was to describe the response of plasma creatine kinase (CK) activity in a sample of African-American men after a bout of eccentric exercise. The study also described signal intensity changes detected by MR in the musculature of the right lower leg.

METHODS

Subjects were 20 male volunteers of African descent (age = 24 +/- 4 [mean +/- SD] yr). Each walked backward for 60 min at 3 km x h(-1) down a 23% grade. Venous blood was sampled before exercise, immediately (0 d) after and 1, 2, 4, and 7 d after exercise for plasma CK assay. Soreness in the plantar flexor muscles was evaluated in 18 subjects at selected times during the 7 d postexercise. Injury to the plantar flexor muscles was evaluated by magnetic resonance imaging (MRI).

RESULTS

The subjects had high baseline plasma CK activity (187 +/- 127 IU x L(-1); 163 +/- 70 IU x L(-1) with one outlier excluded) compared with typical clinical norms. As a group, CK activity was increased (P < 0.05) 4 d (980 +/- 1331 IU L(-1)) and 7 d (1022 +/- 1031 IU L(-1)) postexercise, compared with preexercise. Eleven (55%) of the subjects had large, delayed increases in plasma CK activity ("hyperresponses"). As a group, the plasma CK response was similar to responses of comparison Caucasian subjects. All subjects reported delayed muscle soreness; there was no association between soreness and plasma CK. Every subject showed MRI evidence of injury to plantar flexor muscles postexercise but varying in degree and time course. Plasma CK activity correlated to MRI signal intensity (rho = 0.445).

CONCLUSION

Results suggest that changes in plasma CK activity and skeletal muscle injury in African-American men after eccentric exercise do not differ from the responses of Caucasians.

Staar Collamer intraocular lens: clinical results from the phase I FDA core study

PURPOSE

To assess the early postoperative efficacy and safety of the Staar Collamer intraocular lens (IOL) in small incision cataract surgery.

SETTING

Six private ophthalmology practices geographically distributed throughout the United States.

METHODS

One hundred twenty-five patients with a mean age of 72.1 years were enrolled in the U.S. Food and Drug Administration (FDA) Phase 1 clinical study of the Staar Collamer IOL after having cataract removal by phacoemulsification. Of these, 107 completed 4 to 6 months of follow-up.

RESULTS

At 4 to 6 months postoperatively, 97.1% of patients achieved 20/40 or better corrected visual acuity; 100% of patients without pre-existing pathology (best case) achieved the same result; both results were better than FDA grid values. No persistent sight-threatening complications were reported. Through 6 months, 4.7% of patients required a neodymium:YAG capsulotomy. No IOL dislocations or removals were reported.

CONCLUSION

Results indicate that the Collamer material is safe and effective for platehaptic IOLs used in small incision cataract surgery.

Progression of pleural and parenchymal disease on chest radiographs of workers exposed to amosite asbestos

OBJECTIVES

To determine predictors of progression of pleural and parenchymal disease on the chest radiographs of workers exposed to a short term, intense exposure of amosite asbestos.

METHODS

The first and last of a series of chest radiographs of 887 workers exposed to amosite was interpreted and coded according to International Labour Organisation (ILO) standards by two physicians. Significant predictors of disease progression were found by a linear stepwise regression analysis from among such variables as smoking history, latency (time since first exposure), duration and intensity of exposure, and cytology.

RESULTS

Although most radiographs remained normal, some showed progression of disease with about twice as many patients with abnormalities on the last film. Various combinations of age, intensity of exposure, and time between films were significant predictors of pleural and parenchymal disease and progression of such disease. No predominance of one sided disease was noted. Cytology and smoking were unreliable predictors of disease. Most disease progression was minor, usually of less than two scoring categories.

CONCLUSION

An intense, yet short, exposure to amosite asbestos can produce pleural and parenchymal changes on chest radiographs. The number of those affected roughly doubled over a period spanning 10 to 20 years after exposure. Age and intensity of exposure are the most important predictors of disease.

In situ fracture

A new technique of phacoemulsification is described in which the nucleus is fractured within the capsular bag (in situ). The characteristics of this technique include hydrodissection, division of the nucleus into quadrants, and manipulation of each quadrant into the safe central zone for emulsification. The advantages of this method are safety, speed, and usefulness in almost all degrees of nuclear density and in small undilatable pupils.

A descriptive study of 42 cases of Branhamella catarrhalis pneumonia

PURPOSE

We studied the clinical and laboratory findings of patients with pneumonia due to Moraxella (Branhamella) catarrhalis to better characterize the types of patients who develop this pneumonia, the clinical features of the illness, and the type of and response to drug therapy, as well as the immediate and long-term survival of these patients.

PATIENTS AND METHODS

Patients with sputum samples that met cellular criteria as quality samples and that grew B. catarrhalis as the sole pathogen were identified retrospectively from microbiology records at a regional referral hospital for cardiac and pulmonary diseases. Records of these patients were reviewed to identify patients with radiographic findings of pneumonia. Clinical and laboratory characteristics of these patients were then studied in detail.

RESULTS

Forty-two patients who met the criteria for B. catarrhalis pneumonia were identified. Most patients were elderly (over 65 years; 55 percent), malnourished (69 percent), and had severe chronic obstructive pulmonary disease or another serious underlying disease (98 percent). The seasonal incidence of this pneumonia was October through April (88 percent), with the annual number of cases having increased since 1982. The clinical presentation was typically mild. Interstitial or mixed interstitial-alveolar infiltrates superimposed on pre-existing chronic lung disease was the most common radiographic finding. Approximately 90 percent of sputa were acceptable for Gram stain and contained 10 to more than 50 gram-negative cocci/1,000 x field. All cultures produced a heavy growth of B. catarrhalis, with 67 percent of strains positive for beta-lactamase. No patient had identified bacteremia (zero of 25 tested). Therapy with numerous agents including cefotaxime, amoxicillin/clavulanic acid, and trimethoprim/sulfamethoxazole resulted in a good clinical and bacteriologic response. However, 45 percent of patients died of their underlying diseases on this admission or within three months.

CONCLUSION

These findings provide a good profile of B. catarrhalis pneumonia. Despite the mild character of the illness, the pneumonia occurs in patients with end-stage pulmonary or malignant disease and almost 50 percent of patients die of their underlying diseases within three months.

Capsular opacification associated with silicone implants

This study compares the incidence of significant posterior capsular opacification in the 12 months following surgery in patients who received a sulcus-fixated silicone lens, a bag-fixated poly(methyl methacrylate) (PMMA) lens, or a bag-fixated silicone lens. All procedures were performed by the same surgeon using the same technique. The incidence of capsulotomy was 16.5% with sulcus-fixated silicone lenses, 7.9% with PMMA lenses, and 4.8% with bag-fixated silicone lenses. This confirms the impression that earlier opacification occurs with sulcus-fixated silicone lenses, but the low incidence of opacification with bag-fixated silicone lenses suggests the cause is not the silicone but the location of lens fixation.

Continuous-tear capsulotomy and insertion of a silicone bag lens

Opacification of the posterior capsule and lack of intraocular lens fixation have been recurring problems and have resulted in a gradual shift from sulcus-fixated silicone lenses to bag-fixated silicone lenses. Postoperative capsular contraction, however, can cause capsular tearing in the periphery and intraocular lens decentration. A new method of combining a small circular capsulotomy, cataract removal without anterior capsular rim tearing, and meticulous bag placement of the silicone lens seems to allow centering and secure fixation of the silicone lens.

Correction of preexisting astigmatism at the time of small incision cataract surgery

To reduce preexisting astigmatism in patients having cataract surgery, paired keratotomy incisions of graded lengths were performed at the time of cataract extraction. Small incisions, made possible by foldable silicone implants, were used to make the correction more accurate. The results obtained in 48 patients are analyzed. It appears that this technique is safe, quick, and helpful in reducing preexisting astigmatism.

Induced astigmatism in small incision cataract surgery

The use of smaller cataract incisions is thought to induce less astigmatism, resulting in a more stable refraction. I analyzed the astigmatic changes in 99 cataract/intraocular lens patients with 4.0 mm incisions. Preoperative keratometry measurements were compared with those obtained one week, one month, and three months postoperatively. These changes, analyzed by vector analysis, revealed 0.13 D of induced with-the-rule astigmatism at one week, degrading to 0.22 D of against-the-rule at three months. This compares favorably with previously reported results of 6.0 mm and 10.0 mm incisions. This low amount of induced cylinder and rapid stabilization of the wound confirms an advantage of small incision surgery.