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The Cochrane Database of Systematic... Feb 2017Glaucoma is a leading cause of irreversible blindness worldwide and the second most common cause of blindness after cataracts. The primary treatment for glaucoma aims to... (Review)
Review
BACKGROUND
Glaucoma is a leading cause of irreversible blindness worldwide and the second most common cause of blindness after cataracts. The primary treatment for glaucoma aims to lower intraocular pressure (IOP) with the use of topical medicines. Topical medication instillation techniques, such as eyelid closure and nasolacrimal occlusion when instilling drops, have been proposed as potential methods to increase ocular absorption and decrease systemic absorption of the drops.
OBJECTIVES
To investigate the effectiveness of topical medication instillation techniques compared with usual care or another method of instillation of topical medication in the management of glaucoma or ocular hypertension.
SEARCH METHODS
We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2016, Issue 12), MEDLINE Ovid (1946 to 8 December 2016), Embase Ovid (1947 to 8 December 2016), PubMed (1948 to 8 December 2016), LILACS (Latin American and Caribbean Health Sciences Literature Database) (1982 to 8 December 2016), International Pharmaceutical Abstracts Database (1970 to 8 December 2016), the metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com) (last searched 13 May 2013), ClinicalTrials.gov (www.clinicaltrials.gov) (searched 8 December 2016) and the WHO International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en) (searched 8 December 2016). We did not use any date or language restrictions in the electronic searches for trials.
SELECTION CRITERIA
We included randomized controlled trials which had compared any topical medication instillation technique with usual care or a different method of instillation of topical medication.
DATA COLLECTION AND ANALYSIS
Two review authors independently screened records from the searches for eligibility, assessed the risk of bias, and extracted data. We followed methods recommended by Cochrane.
MAIN RESULTS
We identified two trials (122 eyes of 61 participants) that had evaluated a topical medication instillation technique. We also identified two ongoing trials. Both included trials used a within-person design and administered prostaglandin monotherapy for glaucoma or ocular hypertension. Because the trials evaluated different instillation techniques and assessed different outcomes, we performed no meta-analysis.One trial, conducted in the US, evaluated the effect of eyelid closure (one and three minutes) versus no eyelid closure on lowering IOP. At one to two weeks' follow-up, reduction in IOP was similar in the eyelid closure group and the no eyelid closure group (mean difference (MD) -0.33 mmHg, 95% confidence interval (CI) -0.8 to 1.5; 51 participants; moderate-certainty evidence).The second trial, conducted in Italy, evaluated the effect of using an absorbent cloth to wipe excess fluid after instillation (fluid removal) versus not using an absorbent cloth (no removal) on reducing dermatologic adverse events. At four months' follow-up, eyelashes were shorter among eyes in the fluid removal group compared with the no fluid removal group (MD -1.70 mm, 95% CI -3.46 to 0.06; 10 participants; low-certainty evidence). Fewer eyes showed skin hyperpigmentation in the eyelid region towards the nose in the fluid removal group compared with the no removal group (RR 0.07, 95% CI 0.01 to 0.84; 10 participants; low-certainty evidence); however, the difference was uncertain in the eyelid region towards the temples (RR 0.44, 95% CI 0.07 to 2.66; 10 participants; low-certainty evidence). The effect hypertrichosis (excessive hair growth) was uncertain between groups (RR 1.00, 95% CI 0.17 to 5.98; 10 participants; low-certainty evidence).Neither trial reported other outcomes specified for this review, including the proportion of participants with IOP less than 21 mmHg; participant-reported outcomes related to the ease, convenience, and comfort of instillation techniques; physiologic measurements of systemic absorption; escalation of therapy; mean change in visual fields; optic nerve progression; mean change in best-corrected visual acuity; proportion in whom glaucoma developed; quality of life outcomes; or cost-effectiveness outcomes. Neither trial reported data at follow-up times of more than four months.
AUTHORS' CONCLUSIONS
Evidence to evaluate the effectiveness of topical medication instillation techniques for treatment of glaucoma is lacking. It is unclear what, if any, effects instillation techniques have on topical medical therapy for glaucoma.
Topics: Administration, Ophthalmic; Antihypertensive Agents; Bimatoprost; Eyelashes; Glaucoma; Humans; Intraocular Pressure; Latanoprost; Ophthalmic Solutions; Prostaglandins F, Synthetic; Randomized Controlled Trials as Topic; Travoprost
PubMed: 28218404
DOI: 10.1002/14651858.CD010520.pub2 -
Journal of Breath Research Feb 2017We aimed to assess the evidence for the use of 8-isoprostane in exhaled breath condensate (EBC) as a biomarker in adult asthma. (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
We aimed to assess the evidence for the use of 8-isoprostane in exhaled breath condensate (EBC) as a biomarker in adult asthma.
DESIGN
A systematic review and meta-analysis of EBC 8-isoprostane.
METHODS
We searched a number of online databases (including PubMed, Embase and Scopus) in January 2016. We included studies of adult non-smokers with EBC collection and asthma diagnosis conducted according to recognised guidelines. We aimed to pool data using random effects meta-analysis and assess heterogeneity using I .
RESULTS
We included twenty studies, the findings from which were inconsistent. Seven studies (n = 329) reported 8-isoprostane levels in asthma to be significantly higher than that of control groups, whilst six studies (n = 403) did not. Only four studies were appropriate for inclusion in a random effects meta-analysis of mean difference. This found a statistically significant between-groups difference of 22 pg ml. Confidence in the result is limited by the small number of studies and by substantial statistical heterogeneity (I = 94).
CONCLUSION
The clinical value of EBC 8-isoprostane as a quantitative assessment of oxidative stress in asthma remains unclear due to variability in results and methodological heterogeneity. It is essential to develop a robust and standardised methodology if the use of EBC 8-isoprostane in asthma is to be properly evaluated.
Topics: Adult; Asthma; Biomarkers; Breath Tests; Case-Control Studies; Dinoprost; Exhalation; Humans
PubMed: 28102831
DOI: 10.1088/1752-7163/aa5a8a -
The Cochrane Database of Systematic... Mar 2016Supplementary oxygen is routinely administered to low-risk pregnant women during an elective caesarean section under regional anaesthesia; however, maternal and foetal... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Supplementary oxygen is routinely administered to low-risk pregnant women during an elective caesarean section under regional anaesthesia; however, maternal and foetal outcomes have not been well established. This is an update of a review first published in 2013.
OBJECTIVES
The primary objective was to determine whether supplementary oxygen given to low-risk term pregnant women undergoing elective caesarean section under regional anaesthesia can prevent maternal and neonatal desaturation. The secondary objective was to compare the mean values of maternal and neonatal blood gas levels between mothers who received supplementary oxygen and those who did not (control group).
SEARCH METHODS
We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2014, issue 11), MEDLINE (1948 to November 2014) and EMBASE (1980 to November 2014). The original search was first performed in February 2012. We reran the search in CENTRAL, MEDLINE, EMBASE in February 2016. One potential new study of interest was added to the list of 'Studies awaiting Classification' and will be incorporated into the formal review findings during the next review update.
SELECTION CRITERIA
We included randomized controlled trials (RCTs) of low-risk pregnant women undergoing an elective caesarean section under regional anaesthesia and compared outcomes with, and without, oxygen supplementation.
DATA COLLECTION AND ANALYSIS
Two review authors independently extracted data, assessed methodological quality and performed subgroup and sensitivity analyses.
MAIN RESULTS
We found one new included study in this updated version. In total, our updated review includes 11 trials (with 753 participants). The low quality of evidence showed no significant differences in average Apgar scores at one minute (N = six trials, 519 participants; 95% confidence (CI) -0.16 to 0.31, P = 0.53) and at five minutes (N = six trials, 519 participants; 95% CI -0.06 to 0.06, P = 0.98). None of the 11 trials reported maternal desaturation. The very low quality of evidence showed that in comparison to room air, women in labour receiving supplementary oxygen had higher maternal oxygen saturation (N = three trials, 209 participants), maternal PaO2 (oxygen pressure in the blood; N = six trials, 241 participants), UaPO2 (foetal umbilical arterial blood; N = eight trials, 504 participants; 95% CI 1.8 to 4.9, P < 0.0001) and UvPO2 (foetal umbilical venous blood; N = 10 trials, 683 participants). There was high heterogeneity among these outcomes. A subgroup analysis showed no significant difference in UaPO2 between the two intervention groups in low-risk studies, whereas the high-risk studies showed a benefit for the neonatal oxygen group.
AUTHORS' CONCLUSIONS
Overall, we found no convincing evidence that giving supplementary oxygen to healthy term pregnant women during elective caesarean section under regional anaesthesia is either beneficial or harmful for either the mother or the foetus' short-term clinical outcome as assessed by Apgar scores. Although, there were significant higher maternal and neonatal blood gas values and markers of free radicals when extra oxygen was given, the results should be interpreted with caution due to the low grade quality of the evidence.
Topics: Anesthesia, Conduction; Anesthesia, Obstetrical; Apgar Score; Biomarkers; Cesarean Section; Dinoprost; Elective Surgical Procedures; Female; Fetal Blood; Humans; Malondialdehyde; Oxygen; Pregnancy; Randomized Controlled Trials as Topic
PubMed: 26982519
DOI: 10.1002/14651858.CD006161.pub3 -
Nutrients Mar 2016Dietary advanced glycation end-products (AGEs) form during heating and processing of food products and are widely prevalent in the modern Western diet. Recent systematic... (Review)
Review
Dietary advanced glycation end-products (AGEs) form during heating and processing of food products and are widely prevalent in the modern Western diet. Recent systematic reviews indicate that consumption of dietary AGEs may promote inflammation, oxidative stress and insulin resistance. Experimental evidence indicates that dietary AGEs may also induce renal damage, however, this outcome has not been considered in previous systematic reviews. The purpose of this review was to examine the effect of consumption of a high AGE diet on biomarkers of chronic disease, including chronic kidney disease (CKD), in human randomized controlled trials (RCTs). Six databases (SCOPUS, CINHAL, EMBASE, Medline, Biological abstracts and Web of Science) were searched for randomised controlled dietary trials that compared high AGE intake to low AGE intake in adults with and without obesity, diabetes or CKD. Twelve dietary AGE interventions were identified with a total of 293 participants. A high AGE diet increased circulating tumour necrosis factor-alpha and AGEs in all populations. A high AGE diet increased 8-isoprostanes in healthy adults, and vascular cell adhesion molecule-1 (VCAM-1) in patients with diabetes. Markers of CKD were not widely assessed. The evidence presented indicates that a high AGE diet may contribute to risk factors associated with chronic disease, such as inflammation and oxidative stress, however, due to a lack of high quality randomised trials, more research is required.
Topics: Biomarkers; Diet; Dinoprost; Glycation End Products, Advanced; Humans; Inflammation; Inflammation Mediators; Oxidative Stress; Renal Insufficiency, Chronic; Risk Assessment; Risk Factors; Tumor Necrosis Factor-alpha; Vascular Cell Adhesion Molecule-1
PubMed: 26938557
DOI: 10.3390/nu8030125 -
Current Medical Research and Opinion Jun 2015Prostaglandin-timolol fixed combinations (PG-timolol FCs) are now widely used to reduce intraocular pressure in patients with glaucoma. The efficacy and tolerability of... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Prostaglandin-timolol fixed combinations (PG-timolol FCs) are now widely used to reduce intraocular pressure in patients with glaucoma. The efficacy and tolerability of these drugs are worthy of further exploration. An updated systematic review and meta-analysis was performed to assess the clinical efficacy and tolerability of the three PG-timolol FCs.
METHODS
Pertinent randomized, controlled trials were identified through systematic searches of PubMed, Embase, the Cochrane central register of controlled trials and the Chinese Biomedicine Database. The main efficacy measures were the weighted mean differences (WMDs) for the reduction from baseline to end of treatment in IOP at 9 am, 12 pm and 4 pm and diurnal curve. The main tolerability measures were the odds ratios (ORs) for the incidence of conjunctival hyperemia.
RESULTS
Nine studies involving 991 patients were included in the meta-analysis. Latanoprost-timolol FC (LTFC) and travoprost-timolol FC (TTFC) were not significantly different in lowering IOP at diurnal mean, 9 am, 12 pm and 4 pm. Bimatoprost-timolol FC (BTFC) provided significantly greater efficacy in lowering IOP at the three measurement time points and over the mean diurnal curve than LTFC (diurnal curve: WMD = 0.88 mmHg [95% CI, 0.42 to 1.33]; 9 am: WMD = 1.27 mmHg [0.68 to 1.86]; 12 pm: WMD = 1.16 mmHg [0.85 to 1.46]; 4 pm: WMD = 0.61 mmHg [0.51 to 0.70]) and TTFC (diurnal curve: WMD = 1.94 mmHg [0.19 to 3.68]; 9 am: WMD = 0.68 mmHg [0.15 to 1.21]; 12 pm: WMD = 0.90 mmHg [0.41 to 1.39]; 4 pm: WMD = 1.06 mmHg [0.61 to 1.51]). The incidence of hyperemia was significantly higher with BTFC than LTFC (pooled ORs: 1.85 [1.09 to 3.13]). The incidence of hyperemia was not significantly higher with TTFC than LTFC (pooled ORs: 2.52 [0.85 to 7.46]), and was not significantly higher with BTFC than TTFC (pooled OR: 1.65 [0.48 to 5.70]).
CONCLUSIONS
BTFC provided significantly greater efficacy in lowering IOP at diurnal mean, 9 am, 12 pm and 4 pm than LTFC and TTFC. LTFC was as effective as TTFC in lowering IOP at the four measurement time points and BTFC caused conjunctival hyperemia in more patients than LTFC. Further clinical trials are needed because of the limited number of studies.
Topics: Antihypertensive Agents; Bimatoprost; Drug Combinations; Glaucoma; Humans; Hyperemia; Intraocular Pressure; Latanoprost; Prostaglandins F, Synthetic; Timolol; Travoprost
PubMed: 25867658
DOI: 10.1185/03007995.2015.1039504 -
Archivos de La Sociedad Espanola de... Mar 2015To present a clinical practice guideline update on the medical, laser, and surgical treatment of primary angle closure glaucoma (PACG) in adults. (Review)
Review
OBJECTIVE
To present a clinical practice guideline update on the medical, laser, and surgical treatment of primary angle closure glaucoma (PACG) in adults.
METHODS
Following the formulation of key questions using the PICO scheme (Patient/Problem, Intervention, Comparison, Outcome), a systematic review was performed on the literature published to date, including international clinical practice guidelines. The AMSTAR and Risk of Bias tools were used for evaluating the quality of the information. The level of evidence and grade of recommendation was established following the Scottish Intercollegiate Guidelines Network (SIGN) system.
RESULTS
Following the above methodology, recommendations of medical, laser and surgical treatment in adult PACG and levels of evidence are presented.
CONCLUSIONS
Although the level of scientific evidence for many of the questions raised is not very high, a review is presented on updated treatment recommendations for adult PACG. Among the limitations for the implementation of these recommendations is that most studies have been conducted in Asian populations, and that the effectiveness is measured almost exclusively in terms of reducing intraocular pressure, and does not include visual function, quality of life or cost-effectiveness parameters.
Topics: Adrenergic beta-Antagonists; Adult; Aged; Antihypertensive Agents; Chronic Disease; Combined Modality Therapy; Drug Therapy, Combination; Evidence-Based Medicine; Glaucoma, Angle-Closure; Humans; Intraocular Pressure; Laser Therapy; Light Coagulation; Meta-Analysis as Topic; Middle Aged; Practice Guidelines as Topic; Prostaglandins F, Synthetic; Randomized Controlled Trials as Topic; Tonometry, Ocular; Young Adult
PubMed: 25459683
DOI: 10.1016/j.oftal.2014.09.014 -
The Annals of Pharmacotherapy Dec 2014To systematically review the efficacy and tolerability of 4 prostaglandin analogues (PGAs) as first-line monotherapies for intraocular pressure (IOP) lowering in adult... (Comparative Study)
Comparative Study Meta-Analysis
OBJECTIVE
To systematically review the efficacy and tolerability of 4 prostaglandin analogues (PGAs) as first-line monotherapies for intraocular pressure (IOP) lowering in adult patients with primary open-angle glaucoma or ocular hypertension.
DATA SOURCES
A literature search was performed in PubMed (1965-June 2013) and the Cochrane Library (1980-June 2013) using the search terms ocular hypertension, open-angle glaucoma, prostaglandin analogues, bimatoprost, latanoprost, tafluprost, and travoprost. Additional studies were searched from the reference lists of identified publications.
STUDY SELECTION AND DATA EXTRACTION
In all, 32 randomized controlled trials comparing between PGAs (bimatoprost 0.03%, latanoprost 0.005%, tafluprost 0.0015%, and travoprost 0.004%) or PGA with timolol were selected.
DATA SYNTHESIS
A network meta-analysis was conducted. Using timolol as reference, the relative risks (RRs) of achieving treatment success, defined as the proportion of patients achieving at least 30% IOP reduction, with 95% CIs, were as follows: bimatoprost, 1.59 (1.28-1.98); latanoprost, 1.32 (1.00-1.74); travoprost, 1.33 (1.03-1.72); and tafluprost, 1.10 (0.85-1.42). The mean IOP reductions after 1 month were 1.98 (1.50-2.47), 1.01 (0.55-1.46), 1.08 (0.59-1.57), and 0.46 (-0.41 to 1.33) mm Hg, respectively, and the results were sustained at 3 months. Bimatoprost was associated with the highest risk of developing hyperemia, whereas latanoprost had the lowest risk, with RRs (95% CI) of 4.66 (3.49-6.23) and 2.30 (1.76-3.00), respectively.
CONCLUSIONS
Bimatoprost achieved the highest efficacy in terms of IOP reduction, whereas latanoprost had the most favorable tolerability profile. This review serves to guide selection of the optimal PGA agent for individual patient care in clinical practice.
Topics: Amides; Antihypertensive Agents; Bimatoprost; Cloprostenol; Glaucoma, Open-Angle; Humans; Intraocular Pressure; Latanoprost; Ocular Hypertension; Prostaglandins F; Prostaglandins F, Synthetic; Prostaglandins, Synthetic; Randomized Controlled Trials as Topic; Timolol; Travoprost
PubMed: 25184309
DOI: 10.1177/1060028014548569 -
The Cochrane Database of Systematic... Jun 2014Prostaglandins have been used for induction of labour since the 1960s. This is one of a series of reviews evaluating methods of induction of labour. This review focuses... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Prostaglandins have been used for induction of labour since the 1960s. This is one of a series of reviews evaluating methods of induction of labour. This review focuses on prostaglandins given per vaginam, evaluating these in comparison with placebo (or expectant management) and with each other; prostaglandins (PGE2 and PGF2a); different formulations (gels, tablets, pessaries) and doses.
OBJECTIVES
To determine the effects of vaginal prostaglandins E2 and F2a for third trimester cervical ripening or induction of labour in comparison with placebo/no treatment or other vaginal prostaglandins (except misoprostol).
SEARCH METHODS
We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (1 March 2014) and bibliographies of relevant papers.
SELECTION CRITERIA
Clinical trials comparing vaginal prostaglandins used for third trimester cervical ripening or labour induction with placebo/no treatment, with each other, or other methods listed above it on a predefined list of labour induction methods.
DATA COLLECTION AND ANALYSIS
We assessed studies and extracted data independently.
MAIN RESULTS
Seventy randomised controlled trials (RCTs) (11,487 women) are included. In this update seven new RCTs (778 women) have been added. Two of these new trials compare PGE2 with no treatment, four compare different PGE2 formulations (gels versus tablets, or sustained release pessaries) and one trial compares PGF2a with placebo. The majority of trials were at unclear risk of bias for most domains.Overall, vaginal prostaglandin E2 compared with placebo or no treatment probably reduces the likelihood of vaginal delivery not being achieved within 24 hours. The risk of uterine hyperstimulation with fetal heart rate changes is increased (4.8% versus 1.0%, risk ratio (RR) 3.16, 95% confidence interval (CI) 1.67 to 5.98, 15 trials, 1359 women). The caesarean section rate is probably reduced by about 10% (13.5% versus 14.8%, RR 0.91, 95% CI 0.81 to 1.02, 36 trials, 6599 women). The overall effect on improving maternal and fetal outcomes (across a variety of measures) is uncertain.PGE2 tablets, gels and pessaries (including sustained release preparations) appear to be as effective as each other, small differences are detected between some outcomes, but these maybe due to chance.
AUTHORS' CONCLUSIONS
Prostaglandins PGE2 probably increase the chance of vaginal delivery in 24 hours, they increase uterine hyperstimulation with fetal heart changes but do not effect or may reduce caesarean section rates. They increase the likelihood of cervical change, with no increase in operative delivery rates. PGE2 tablets, gels and pessaries appear to be as effective as each other, any differences between formulations are marginal but may be important.
Topics: Administration, Intravaginal; Dinoprost; Dinoprostone; Female; Humans; Labor, Induced; Oxytocics; Pregnancy; Randomized Controlled Trials as Topic; Term Birth
PubMed: 24941907
DOI: 10.1002/14651858.CD003101.pub3 -
Journal of Glaucoma Jan 2014To assess the relative efficacy and tolerability of preservative-free latanoprost (T2345) compared with other prostaglandin analogues (PGA) for the treatment of... (Comparative Study)
Comparative Study Meta-Analysis
Relative efficacy and safety of preservative-free latanoprost (T2345) for the treatment of open-angle glaucoma and ocular hypertension: an adjusted Indirect comparison meta-analysis of randomized clinical trials.
AIM
To assess the relative efficacy and tolerability of preservative-free latanoprost (T2345) compared with other prostaglandin analogues (PGA) for the treatment of open-angle glaucoma and ocular hypertension by adjusted indirect comparison meta-analysis.
METHODS
Randomized, controlled trials evaluating PGA for the treatment of open-angle glaucoma and ocular hypertension were identified by a systematic literature review in MEDLINE, EMBASE, and Cochrane Controlled Trials Register (up to December 2011) databases. The effect size for each treatment and heterogeneity were assessed by classical pairwise meta-analysis (direct comparisons). Adjusted indirect comparisons were performed by using Bucher method. The main endpoints were intraocular pressure (IOP) measured at 3 months and incidence of hyperemia.
RESULTS
Twenty-one studies were included in the meta-analysis. No statistically significant differences in IOP at 3 months were seen between T2345 and travoprost [preserved with benzalkonium chloride (BAK), polyquaternium-1 or sofzia], and other BAK-preserved PGA: bimatoprost 0.03%, bimatoprost 0.01%, or latanoprost. T2345 was statistically significantly superior to BAK-tafluprost (mean difference: 0.47 mm Hg, 95% confidence interval, [-1.52;-0.28]). The risk of hyperemia was statistically significantly lower with T2345 than with all the other PGA.
CONCLUSIONS
Indirect comparisons never found preservative-free latanoprost (T2345) to be statistically significantly inferior to the other PGA in terms of efficacy on IOP and showed statistically significant superiority over BAK-tafluprost. The risk of hyperemia was statistically significantly lower with T2345 than with all the other PGA.
Topics: Aged; Antihypertensive Agents; Benzalkonium Compounds; Female; Glaucoma, Open-Angle; Humans; Intraocular Pressure; Latanoprost; Male; Middle Aged; Ocular Hypertension; Ophthalmic Solutions; Polymers; Preservatives, Pharmaceutical; Prostaglandins F, Synthetic; Randomized Controlled Trials as Topic; Tonometry, Ocular; Treatment Outcome
PubMed: 23881267
DOI: 10.1097/IJG.0b013e3182a075e6 -
The Cochrane Database of Systematic... Jun 2013Supplementary oxygen is routinely administered to low-risk pregnant women during an elective caesarean section under regional anaesthesia; however, maternal and foetal... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Supplementary oxygen is routinely administered to low-risk pregnant women during an elective caesarean section under regional anaesthesia; however, maternal and foetal outcomes have not been well established.
OBJECTIVES
The primary objective was to determine whether supplementary oxygen given to low-risk term pregnant women undergoing elective caesarean section under regional anaesthesia can prevent maternal and neonatal desaturation. The secondary objective was to compare the mean values of maternal and neonatal blood gas levels between mothers who received supplementary oxygen and those who did not (control group).
SEARCH METHODS
We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 2, 2012), MEDLINE (1948 to February 2012) and EMBASE (1980 to February 2012). We did not apply language restrictions.
SELECTION CRITERIA
We included randomized controlled trials of low-risk pregnant women undergoing an elective caesarean section under regional anaesthesia and compared outcomes with, and without, oxygen supplementation.
DATA COLLECTION AND ANALYSIS
Two review authors independently extracted data, assessed methodological quality and performed subgroup and sensitivity analyses.
MAIN RESULTS
We included 10 trials with a total of 683 participants. Supplementary oxygen administration varied widely in dose and duration between trials. No cases of maternal desaturation were reported, although none of the 10 trials focused on maternal desaturation. Significant differences were noted in maternal oxygen saturation (higher with oxygen, N = three trials; mean difference (MD) 1.6%, 95% confidence interval (CI) 0.8 to 2.3, P < 0.0001), maternal PaO2 (oxygen pressure in the blood; higher with oxygen, N = six trials; MD 141.8 mm Hg, 95% CI 109.3 to 174.3, P < 0.00001), neonatal UaPO2 (foetal umbilical arterial blood; higher with oxygen, N = eight trials; MD 3.3 mm Hg, 95% CI 1.8 to 4.9, P < 0.0001) and UvPO2 (foetal umbilical venous blood; higher with oxygen, N = 10 trials; MD 5.9 mm Hg, 95% CI 3.2 to 8.5, P < 0.0001). No significant differences were reported in neonatal UapH (N = eight trials; MD 0.00, 95% CI -0.01 to 0.00, P = 0.26) and in average Apgar scores at one minute (N = five trials; MD 0.07, 95% CI -0.20 to 0.34, P = 0.6) and at five minutes (N = five trials; MD 0.00, 95% CI -0.06 to 0.05, P = 0.91).Only two out of 10 trials had a low risk of bias in all categories. When we separated the studies into low risk and high risk for bias, we found substantial statistical heterogeneity. None of the low-risk studies showed a significant difference in neonatal UaPO2 between the two intervention groups, whereas the high-risk studies showed a benefit for the neonatal oxygen group.The level of oxygen free radicals (malondialdehyde (MDA) and 8-isoprostane) was higher in participants who received supplementary oxygen (N = two trials; MD 0.2 µmol/L, 95% CI 0.1 to 0.4, P = 0.0002; MD 64.3 pg/mL, 95% CI 51.7 to 76.8, P < 0.00001, respectively).
AUTHORS' CONCLUSIONS
Current evidence suggests that supplementary oxygen given to healthy term pregnant women during elective caesarean section under regional anaesthesia is associated with higher maternal and neonatal oxygen levels (maternal SpO2, PaO2, UaPO2 and UvPO2) and higher levels of oxygen free radicals. However, the intervention was neither beneficial nor harmful to the neonate's short-term clinical outcome as assessed by Apgar scores.
Topics: Anesthesia, Conduction; Anesthesia, Obstetrical; Apgar Score; Cesarean Section; Dinoprost; Elective Surgical Procedures; Female; Humans; Malondialdehyde; Oxygen; Pregnancy; Randomized Controlled Trials as Topic
PubMed: 23813306
DOI: 10.1002/14651858.CD006161.pub2