What is the impact of the fluid challenge technique on diagnosis of fluid responsiveness? A systematic review and meta-analysis.

BACKGROUND: The fluid challenge is considered the gold standard for diagnosis of fluid responsiveness. The objective of this study was to describe the fluid challenge techniques reported in fluid responsiveness studies and to assess the difference in the proportion of 'responders,' (PR) depending on the type of fluid, volume, duration of infusion and timing of assessment. METHODS: Searches of MEDLINE and Embase were performed for studies using the fluid challenge as a test of cardiac preload with a description of the technique, a reported definition of fluid responsiveness and PR. The primary outcome was the mean PR, depending on volume of fluid, type of fluids, rate of infusion and time of assessment. RESULTS: A total of 85 studies (3601 patients) were included in the analysis. The PR were 54.4% (95% CI 46.9-62.7) where <500 ml was administered, 57.2% (95% CI 52.9-61.0) where 500 ml was administered and 60.5% (95% CI 35.9-79.2) where >500 ml was administered (p = 0.71). The PR was not affected by type of fluid. The PR was similar among patients administered a fluid challenge for <15 minutes (59.2%, 95% CI 54.2-64.1) and for 15-30 minutes (57.7%, 95% CI 52.4-62.4, p = 1). Where the infusion time was ≥30 minutes, there was a lower PR of 49.9% (95% CI 45.6-54, p = 0.04). Response was assessed at the end of fluid challenge, between 1 and 10 minutes, and >10 minutes after the fluid challenge. The proportions of responders were 53.9%, 57.7% and 52.3%, respectively (p = 0.47). CONCLUSIONS: The PR decreases with a long infusion time. A standard technique for fluid challenge is desirable.

Severe Intraoperative Hyperglycemia Is Independently Associated With Postoperative Composite Infection After Craniotomy: An Observational Study.

BACKGROUND: Postoperative infection after craniotomy carries an increased risk of morbidity and mortality. Identification and correction of the risk factors should be prioritized. The association of intraoperative hyperglycemia with postoperative infections in patients undergoing craniotomy is inadequately studied. METHODS: A total of 224 patients were prospectively enrolled in 2 major medical centers to assess whether severe intraoperative hyperglycemia (SIH, blood glucose ≥180 mg/dL) is associated with an increased risk of postoperative infection in patients undergoing craniotomy. Arterial blood samples were drawn and analyzed immediately after anesthetic induction and again before tracheal extubation. The new onset of any type of infection within 7 days after craniotomy was determined. RESULTS: The incidence of new postoperative composite infection was 10% (n = 22) within the first week after craniotomy. Weight, sex, American Society of Anesthesiologists score, preoperative and/or intraoperative steroid use, and diabetes mellitus were not associated with postoperative infection. SIH was independently associated with postoperative infection (odds ratio [95% confidence interval], 4.17 [1.50-11.56], P = .006) after fitting a multiple logistic regression model to adjust for emergency surgery, length of surgery, and age ≥65 years. CONCLUSIONS: SIH is independently associated with postoperative new-onset composite infections in patients undergoing craniotomy. Whether prevention of SIH during craniotomy results in a reduced postoperative risk of infection is unknown and needs to be appraised by further study.

Idiopathic Intracranial Hypertension Papillopathy due to Hormonal Changes during Pregnancy.

Background: The underlying mechanisms of papilledema associated with intracranial hypertension remain unclear. A case of bilateral papillary edema in a patient with chronic idiopathic intracranial hypertension who was asymptomatic during her two pregnancies is reported. Case Presentation. A 19-year-old Caucasian female, in her third month of pregnancy, complained of difficulties with close reading. The patient's visual acuity was 20/20 on the Snellen chart and improved with a 0.50 D correction in both eyes. Near vision and slit lamp examinations revealed normal findings bilaterally. However, a fundus examination showed bilateral papillary edema without evidence of hemorrhages or neovascularization. Blood tests were unremarkable, except for a slight increase in C-reactive protein levels. The patient had a prepregnancy weight of 63 kilograms, with a BMI of 24.91 kg/m2. Magnetic resonance imaging of the brain revealed features consistent with chronic idiopathic intracranial hypertension, which resolved after delivery. Two and a half years later, during a subsequent pregnancy, the patient experienced a recurrence of bilateral papillary edema due to the IIH. It was managed similarly as the first occurrence, resulting in bilateral anatomical and functional recovery. Recent research revealed that, during pregnancy, hormones interact with the central nervous system, leading to an increase in the size of neurons which could potentially result in intracranial hypertension. Conclusions: The influence of hormonal fluctuations during pregnancy on the development of transient central nervous system abnormalities in individuals with chronic intracranial hypertension, leading to papillary edema, remains a matter of debate.

Bilateral diabetic papillopathy developed after starting insulin treatment. Potential toxic effect of insulin? A case report.

BACKGROUND: Diabetic papillopathy is a complication of diabetes. It presents with edema, uni or bilateral and vascular alteration of the anterior optic nerve. Often this complication is observed in patients with severe diabetic retinopathy, but is rarely observed in isolated form. Some authors believe that diabetic papillitis is a particular form of non-arteritic anterior ischemic optic neuropathy (NAION). But there is important evidence that confers an inflammatory component to diabetic papillopathy. We report in this work a rare case of isolated acute bilateral diabetic papillopathy developed in a diabetic patient after adding the insulin to the oral hypoglycemic therapy. CASE PRESENTATION: Male patient, 49-years-old, diabetic type 2, with altered glycemia at follow up, with clinical history of HbA1c 8% to 12% in the last 2 years, on oral hypoglycemic therapy for 10 years. He never had a history of diabetic retinopathy. At the last check-up, this patient presented bilateral papillopathy, without reduction of visual acuity bilaterally. The patient reports he added 10 days before the insulin therapy to the oral hypoglycemic therapy, under medical supervision. Hematochemical and serological tests were requested, which excluded the presence of inflammatory and infectious diseases. The brain magnetic resonance imaging (MRI) with gadolinium excluded the hypothesis of optic neuritis or intracranial hypertension. Cardio-circulatory tests were normal. Fluorescein angiographic examinations and optical coherence tomography (oct) confirmed the bilateral edema and the thickening of optic nerve without other retinal damage. Therefore he was diagnosed with bilateral diabetic papillopathy. Then, diabetologists added pump insulin treatment to the oral hypoglycemic therapy. After 2 months, his blood sugar levels and HbA1C improved and papillopathy regressed. CONCLUSION: We have reported a rare case of bilateral acute diabetic papillopathy associated with the addition of insulin to the oral hypoglycemic therapy. A randomized control study with diabetic patients, would be useful to verify the possible injuries of the optic nerves during the delicate transition to insulin therapy.