The potentiation of "incomplete" mouse monoclonal anti-Lea agglutination with colloids

Mouse monoclonal anti-Lea produced in this center was found to agglutinate only Le(a+) red cells which had been modified with proteases. In order to provide a stable medium in which the monoclonal anti-Lea would directly agglutinate unmodified red cells, the potentiating effect of a variety of colloids was assessed. Satisfactory results were obtained when 10 percent (wt/vol) dextran and 2 percent (wt/vol) bovine serum albumin were added to the culture supernatant containing anti-Lea. It is suggested that direct hemagglutination mediated by these colloids resulted from a combination of increased antibody uptake by Le(a+) red cells and change in the shape of these red cells induced by dextran.     

The prevalence and impact of pain after day-care tubal ligation surgery

Empirical data from controlled studies using standardized, reliable measures on the amount and quality of pain after laparoscopic tubal ligation and the consequences of this pain on the activities of daily living are extremely scarce. In a study of 54 women admitted to a day-care unit for this procedure, validated measures were utilized to assess the incidence, intensity and duration of pain after tubal ligation (McGill Pain Questionnaire) and the impact of pain on the activities of daily living (Modified Functional Assessment Inventory). Psychological measures (Brief Symptom Inventory, Kranz Health Opinion Survey, and the State-Trait Anxiety Inventory) were employed to test their use as possible predictors for pain, analgesic usage and the time taken to resume a normal activity level after tubal ligation surgery. The results showed that pain is a significant problem after tubal ligation although pain rating scores over the 7-day study period were lower than those reported after major abdominal surgery. Eighty-five percent of our sample reported that pain and/or fatigue impacted on their recovery and contributed to an average delay of return to normal activity level of 4.4 days, not including the day of surgery. The psychological measures did not prove to be strong predictors of postoperative pain, time of return to normal activity level or analgesic usage. The most powerful predictor of return to normal activity was the total amount of pain experienced, as measured by the McGill Pain Questionnaire, during the 7 day post-operative period.     

Impact of membrane oxygenators on pulsatile versus nonpulsatile perfusion in a neonatal model

We investigated the effects of two new hollow-fiber membrane oxygenators, the Capiox SX10 and the Lilliput 901, on pulsatile versus nonpulsatile perfusion in an in vitro model designed to simulate a 3 kg infant. The experiments were divided into eight groups (six pulsatile and two nonpulsatile), according to the equipment and settings used. Each group included six tests. In all experiments, the pseudo-patient's mean arterial pressure was 40 mmHg, and the pump flow rate was 550 ml/min. During pulsatile cardiopulmonary bypass, the pump's base flow was set at 30%, and the pump rate was set at 80, 100, 120, 140, or 150 beats/min. The PUMP START and PUMP STOP timing points were adjusted to produce different pulse-width settings. We were especially interested in evaluating the pre- and postoxygenator extracorporeal circuit pressure (ECP), the oxygenator pressure drop, and the precannula ECP. When used with a pulsatile roller pump, the Capiox produced a significantly lower preoxygenator ECP than the Lilliput (p < 0.001); moreover, the Capiox yielded a significantly lower oxygenator pressure drop (p < 0.001). During nonpulsatile perfusion, the Capiox again produced a lower preoxygenator ECP than the Lilliput (p < 0.001). These results suggest that the Capiox may be more suitable than the Lilliput when the pulsatile flow is employed, and pulsatile flow does not increase the ECP with either oxygenator.     

Identifying Reasons for Failed Same-Day Discharge Following Primary Total Hip Arthroplasty

Background

As total hip arthroplasty (THA) gains popularity in ambulatory surgery centers, it is important to understand the causes of failed same-day discharge (SDD). The purpose of this study is to (1) identify reasons for an overnight stay among patients selected as candidates for SDD following THA and (2) determine what pre-operative factors are more common among patients who fail SDD.

Longer hospital stay,more complications,and increased mortality but substantially improved function after knee replacement in older patients: A study of 3,144 primary unilateral total knee replacements

Background and purpose

Total knee replacement (TKR) is being increasingly performed in elderly patients, yet there is little information on specific requirements and complication rates encountered by this group. We assessed whether elderly patients undergoing TKR had different length of stay, requirements, complication rates, and functional outcomes compared to younger counterparts.

Patients and methods

We analyzed prospectively gathered data on 3,144 consecutive primary TKRs (in 2,092 patients aged less than 75 years, 694 patients aged between 75 and 80 years, and 358 patients aged over 80 years at the time of surgery).

Results

Incidence of blood transfusion, urinary catheterization, postoperative confusion, cardiac arrhythmia, and 1-year mortality increased with age, even after adjusting for confounding factors, whereas the incidences of chest infection and mortality at 1 month were highest in those aged 75–80. Rates of thromboembolism, prosthetic infection, and revision were similar in the 3 age groups. All groups showed similar substantial improvements in American Knee Society (AKS) knee scores, which were maintained at 5 years. Older patients had smaller improvements in AKS function score, which deteriorated between 3 and 5 years postoperatively, in contrast to the younger group.

Interpretation

Elderly people stand to gain considerably from TKR, particularly in terms of pain relief, and they should not be denied surgery based solely on age. However, they should be warned that they can expect a longer length of stay, a higher requirement for blood transfusion and/or urinary catheterization, and more medical complications postoperatively. Mortality was also higher in the older age groups. The risks have been quantified to assist in perioperative counselling, informed consent, and healthcare planning.Healthcare systems and medical professionals will need to cater for increasing numbers of total knee replacements (TKRs) in elderly people in the coming years (Carr et al. 2012), but little is known about inpatient requirements and the postoperative complications suffered by this particular patient group. Some studies have shown good joint-specific pain relief and functional benefits from TKR in the elderly (Anderson et al. 1996, Birdsall et al. 1999), although it has been suggested that elderly patients may attain lower global function than their younger counterparts (Clement et al. 2011, Kennedy et al. 2013). However, studies attempting to describe complications in the elderly undergoing TKR have been small (Zicat et al. 1993, Hosick et al. 1994, Joshi et al. 2003), have lacked comparator groups (Hosick et al. 1994, Joshi et al. 2003), or have failed to quantify the time scales within which complications have occurred (Clement et al. 2011, Kennedy et al. 2013). Other studies and registries have been based on discharge summary databases without specific patient follow-up (Kreder et al. 2005, Mahomed et al. 2005, Scottish Arthroplasty Project, 2012). They therefore relied on third-party coding of discharge summaries and reported only on mortality during the index admission (Kreder et al. 2005) or selected complications requiring hospital re-admission within 30 or 90 days (Kreder et al. 2005, Mahomed et al. 2005, Scottish Arthroplasty Project, 2012).The aim of this study was to determine whether elderly patients undergoing TKR had different postoperative length of stay, inpatient requirements (i.e. blood transfusion and urinary catheterization), complication rates, and mortality rates to those of their younger counterparts. Functional outcomes were assessed as a secondary outcome measure, to determine whether elderly patients gained benefit comparable to that of their younger counterparts, independently of recorded admission requirements and complications.