The effects of frequent nocturnal home hemodialysis: the Frequent Hemodialysis Network Nocturnal Trial.

Prior small studies have shown multiple benefits of frequent nocturnal hemodialysis compared to conventional three times per week treatments. To study this further, we randomized 87 patients to three times per week conventional hemodialysis or to nocturnal hemodialysis six times per week, all with single-use high-flux dialyzers. The 45 patients in the frequent nocturnal arm had a 1.82-fold higher mean weekly stdKt/V(urea), a 1.74-fold higher average number of treatments per week, and a 2.45-fold higher average weekly treatment time than the 42 patients in the conventional arm. We did not find a significant effect of nocturnal hemodialysis for either of the two coprimary outcomes (death or left ventricular mass (measured by MRI) with a hazard ratio of 0.68, or of death or RAND Physical Health Composite with a hazard ratio of 0.91). Possible explanations for the left ventricular mass result include limited sample size and patient characteristics. Secondary outcomes included cognitive performance, self-reported depression, laboratory markers of nutrition, mineral metabolism and anemia, blood pressure and rates of hospitalization, and vascular access interventions. Patients in the nocturnal arm had improved control of hyperphosphatemia and hypertension, but no significant benefit among the other main secondary outcomes. There was a trend for increased vascular access events in the nocturnal arm. Thus, we were unable to demonstrate a definitive benefit of more frequent nocturnal hemodialysis for either coprimary outcome.

Gastric electrical stimulation at proximal stomach induces gastric relaxation in dogs.

Gastric electrical stimulation (GES) improves symptoms in patients with gastroparesis. However, the underlying mechanisms remain unclear. To determine if GES at proximal and distal stomach could affect the biomechanical properties of the stomach, thus contributing to the beneficial effect of GES. Four pairs of electrodes were implanted along the greater curvature of the stomach in seven dogs. Gastric tone and compliance was assessed with a barostat. Measurements were obtained randomly during control and proximal and distal stimulation (4 mA, 375 ms and 6/18 cpm). Data as mean or median (25-75th percentiles). Gastric compliance was not affected by proximal and distal GES. Gastric tone was significantly reduced during proximal GES: 82.0 (66.8, 89.1) mL vs control 49.7 (39.6,75.9) mL at 6 cpm (P = 0.016), and 90.6 (54.5, 117.9) mL vs control 62.8 (39.6, 75.9) mL at 18 cpm (P = 0.031). Tone was not affected by distal GES at 6 cpm: 95.8 (46.3, 106.7) mL vs control 75.2 (49.7, 86.1) mL (P = 0.47) and at 18 cpm: 80.4 (38.1, 170.3) mL vs control 62.8 (44.6, 156.3) mL (P = 0.44). Proximal GES induces gastric relaxation. This effect, if seen also in humans, may explain, in part, the symptomatic improvement associated with GES therapy in patients with gastroparesis.

Outcomes of combined cataract extraction, lens implantation, and trabeculectomy surgeries.

PURPOSE: To report outcomes and their association with preoperative and intraoperative factors of 456 combined cataract and glaucoma operations. METHODS: A concurrent series (from January 1, 1987, to October 1, 1997) of one surgeon's consecutive 585 (456 patients) combined cataract extraction, intraocular lens implantation, and trabeculectomy surgeries, some with intraoperative mitomycin C and/or postoperative subconjunctival 5-fluorouracil. The study was a retrospective outcomes analysis for the first 191 operations (before June 10, 1992) and, subsequently, concurrent outcomes analysis for the latter 394 operations. Main outcome measures included postoperative visual acuity, intraocular pressure, number of glaucoma medications, intraoperative and postoperative adverse event rates, and reoperation for glaucoma or other ocular surgical or laser intervention. RESULTS: Visual acuity was improved at the time of last follow-up in 402 (88.2%) of 456 first operated eyes of the 456 patients. Increasing age (coefficient = 0.025; CI [confidence interval], 0.017 to 0.33; P <.0001) was associated with a decreased likelihood of improved visual acuity, and a more recent operation (coefficient = 0.0037; 95% CI, -0.0064 to -0.0010, P =.0082) was associated with an increased likelihood of improved visual acuity. Forty-one (9.0%) of 456 eyes had reoperation to control intraocular pressure. Glaucoma reoperation was most strongly associated with a preoperative diagnosis other than primary open-angle, pigmentary, or pseudoexfoliative glaucoma, a history of previous ocular surgery, and high preoperative intraocular pressure. Mean intraocular pressure reduced 5.5 mm Hg from 21.8 mm Hg preoperatively to 16.3 mm Hg postoperatively and mean glaucoma medication from 2.0 to 0.9 medications. Mitomycin C or 5-fluorouracil use was significantly associated with a lower postoperative intraocular pressure and reduced postoperative glaucoma medication. Major postoperative adverse event or other reoperation (not for glaucoma) occurred in 12 (2.6%) of first operated eyes. CONCLUSIONS: Combined surgery outcomes in 456 first-operated eyes of 456 patients showed 88.2% improved visual acuity, 9% re-operation rate, 5.5 mm Hg mean intraocular pressure reduction, 1.1 glaucoma medication reduction, and a low major postoperative adverse event rate. Type of glaucoma, previous ocular surgery, and high preoperative intraocular pressure were the best predictors for the need for reoperation for glaucoma after combined surgery. Mitomycin C and/or 5-fluorouracil provided a greater reduction of mean intraocular pressure and glaucoma medication compared with patients not receiving these agents.

Complications of postmastectomy breast reconstructions in smokers, ex-smokers, and nonsmokers.

Smoking results in impaired wound healing and poor surgical results. In this retrospective study, we compared outcomes in 155 smokers, 76 ex-smokers, and 517 nonsmokers who received postmastectomy breast reconstructions during a 10-year period. Ex-smokers were defined as those who had quit smoking at least 3 weeks before surgery. Transverse rectus abdominis musculocutaneous (TRAM) flap surgery was performed significantly less often in smokers (24.5 percent) than in ex-smokers (30.3 percent) or nonsmokers (39.1 percent) (p < 0.001). Tissue expansion followed by implant was performed in 112 smokers (72.3 percent), 50 (65.8 percent) ex-smokers, and 304 nonsmokers (58.8 percent) (p = 0.002). The overall complication rate in smokers was 39.4 percent, compared with 25 percent in ex-smokers and 25.9 percent in nonsmokers, which is statistically significant (p = 0.002). Mastectomy flap necrosis developed in 12 smokers (7.7 percent), 2 ex-smokers (2.6 percent), and 8 nonsmokers (1.5 percent) (p < 0.001). Among patients receiving TR4AM flaps, fat necrosis developed in 10 smokers (26.3 percent), 2 ex-smokers (8.7 percent), and 17 nonsmokers (8.4 percent). Abdominal wall necrosis was more common in smokers (7.9 percent) than in ex-smokers (4.3 percent) or nonsmokers (1.0 percent). In this large series, tissue expansion was performed more often in smokers than was autogenous reconstruction. Complications were significantly more frequent in smokers. Mastectomy flap necrosis was significantly more frequent in smokers, regardless of the type of reconstruction. Breast reconstruction should be done with caution in smokers. Ex-smokers had complication rates similar to those of nonsmokers. Smokers undergoing reconstruction should be strongly urged to stop smoking at least 3 weeks before their surgery.