Changes in jugular bulb oxygenation in patients undergoing warm coronary artery bypass surgery (34-37 degrees C)

BACKGROUND AND OBJECTIVE: Imbalance between cerebral oxygen supply and demand is thought to play an important role in the development of cerebral injury during cardiac surgery with cardiopulmonary bypass. METHODS: We studied jugular bulb oxygen saturation, jugular bulb oxygen tension, arterial-jugular bulb oxygen content difference and oxygen extraction ratio in 20 patients undergoing warm coronary artery bypass surgery (34-37 degrees C) with pH-stat blood gas management. RESULTS: Only two patients showed desaturation (jugular bulb oxygen saturation < 50%) at 5 min on bypass, and none from 20 min onwards. Multiple regression models were performed after using bypass temperature, mean arterial pressure, cerebral perfusion pressure, haemoglobin concentration and arterial carbon dioxide tension as independent variables, and arterial-jugular bulb oxygen content difference, jugular bulb oxygen saturation, oxygen extraction ratio and jugular bulb oxygen tension as individual dependent variables. CONCLUSIONS: We found that jugular bulb oxygen saturation, jugular bulb oxygen tension and oxygen extraction ratio are mainly dependent on arterial carbon dioxide tension, and arterial-jugular bulb oxygen content difference is dependent on arterial carbon dioxide tension and the bypass temperature. Our results suggest jugular bulb oxygenation is mainly dependent on arterial carbon dioxide tension during warm cardiopulmonary bypass.     

Improvement in erectile function on vardenafil treatment correlates with treatment satisfaction in both patients and their partners

OBJECTIVE: To evaluate the effect of vardenafil on both erectile function (EF) and treatment satisfaction (an aspect of quality of life) in men and their partners, as erectile dysfunction (ED) has a profound effect on patients' quality of life and that of their partners, and treatment for ED tends to be focused on improving functional measures of EF. PATIENTS, SUBJECTS AND METHODS: For this randomized, double-blind, placebo-controlled trial, men with ED for >6 months, according to the USA National Institutes of Health Consensus Statement, were recruited. In all, 611 patients were randomized to treatment with either vardenafil (10 mg for 4 weeks, titrated to preferred dose, 5, 10 or 20 mg, during the next 8 weeks, and maintained at preferred dose for the following 14 weeks), or placebo. RESULTS: At 18 weeks (primary endpoint), the mean improvement in the EF domain of International Index of EF (IIEF-EF) vs baseline was significantly greater with vardenafil than placebo (12.70 vs 1.69, P < 0.001). This was accompanied by significant benefits at 26 weeks and in various secondary variables relating to sexual satisfaction. Qualitative assessment of the treatment effect revealed three categories of importance to patients: effectiveness, confidence and quality of life. There were significant linear correlations between patients' EF and treatment satisfaction, and between patients' EF and their partners' treatment satisfaction. CONCLUSIONS: Functional improvements in response to vardenafil treatment are significantly correlated with treatment satisfaction for both patients with ED and their partners. These findings apply to patients with a wide range of baseline characteristics.     

Fungal wound infection (not colonization) is independently associated with mortality in burn patients

OBJECTIVE: To analyze the occurrence of fungal wound infection (FWI) after thermal injury and its relationship to mortality. BACKGROUND: FWI is an uncommon but potentially lethal complication of severe thermal injury. METHODS: The records of patients with thermal burns admitted to a single burn center (1991-2002) were reviewed. Analyses accounted for total burn size (TBS, percentage body surface area), full-thickness burn size (FTBS, percentage body surface area), age, inhalation injury, sex, and fungal-status category. Fungal colonization and infection were determined histopathologically. RESULTS: Criteria for inclusion were met by 2651 patients. Each patient's fungal-status category was defined according to the deepest level of fungal involvement observed during the hospital course: no fungus (2476 patients), fungal wound colonization (FWC, 121 patients), or fungal wound infection (FWI, 54 patients). Median TBS (9%, 47%, 64%, respectively) and mortality (5%, 27%, 76%, respectively) varied significantly among fungal-status groups. Logistic regression was used to detect significant independent associations. FWI was associated with higher TBS. Mortality was associated with TBS, FTBS, inhalation injury, FWI, and age. Unlike FWI, FWC was not independently related to mortality, the greater observed mortality in FWC being explained by other variables such as TBS. The odds ratio for FWI (8.16) suggested about the same mortality impact as augmenting TBS by 33%. A midrange TBS of 30% to 60% was required for most of the detectable association of FWI with mortality. CONCLUSIONS: FWI accompanies larger burns and is associated with mortality in burn patients, particularly in those with TBS 30% to 60%. This association is independent of burn size, inhalation injury, and age.     

Revision endoscopic frontal sinus surgery with surgical navigation.

BACKGROUND: Revision surgery of the frontal sinus remains one of the most difficult operations for the endoscopic surgeon. Most agree that knowledge and recognition of its complex anatomy and sparing of frontal recess mucosa are keys to a successful operation. The use of surgical navigation systems may allow for more precise dissections and greater rates of frontal recess patency. METHODS: Retrospective review of all patients undergoing revision endoscopic frontal sinus surgery with surgical navigation was performed with a minimum 24-month follow-up. RESULTS: Sixty-seven patients underwent revision endoscopic frontal sinus surgery with surgical navigation. The average follow-up was 32 months. Fifty-eight (86.6%) had a patent frontal recess and significant subjective improvement in symptoms. No patient underwent external frontal sinus obliteration, and there were no major complications. CONCLUSIONS: Endoscopic techniques with surgical navigation are effective in revision frontal sinus cases. The dissection of remnant agger nasi, obstructing frontal and supraorbital cells are necessary to widen the anterior-posterior as well as the medial-lateral dimensions of the recess. Computer navigational systems appear to serve as a valuable adjunct in preoperative planning and safe intraoperative dissection.     

Preseason strength and flexibility imbalances associated with athletic injuries in female collegiate athletes

One hundred thirty-eight female collegiate athletes, participating in eight weightbearing varsity sports, were administered preseason strength and flexibility tests and followed for injuries during their sports seasons. Strength was measured as the maximal isokinetic torque of the right and left knee flexors and knee extensors at 30 and 180 deg/sec. Flexibility was measured as the active range of motion of several lower body joints. An athletic trainer evaluated and recorded injuries occurring to the athletes in practice or competition. Forty percent of the women suffered one or more injuries. Athletes experienced more lower extremity injuries if they had: 1) a right knee flexor 15% stronger than the left knee flexor at 180 deg/sec; 2) a right hip extensor 15% more flexible than the left hip extensor; 3) a knee flexor/knee extensor ratio of less than 0.75 at 180 deg/sec. There was a trend for higher injury rates to be associated with knee flexor or hip extensor imbalances of 15% or more on either side of the body. These data demonstrate that specific strength and flexibility imbalances are associated with lower extremity injuries in female collegiate athletes.     

The Influence of Vibration on Muscle Activation and Rate of Force Development during Maximal Isometric Contractions

At present there appears to be a need for research conducted on the effects of vibration on the contractile ability of skeletal muscle tissue. The aim of this study was to address this issue by examining the effects of a superimposed muscle/tendon vibration at 50.42±1.16 Hz (acceleration 13.24 ± 0.18ms^-2: displacement ≈5mm) on muscular activation and maximal isometric contraction. Sixteen participants with a mean age, body mass, and height of 22 ± 4.4 years, 73.2 ± 11.7 kg and 173.1 ± 9.7 cms, respectively, were recruited for this study. Electromyography and accelerometry from the rectus femoris, and maximal isometric force data characteristics were collected from the dominant limb under conditions of vibration, and no-vibration. A superimposed 50 Hz vibration was used during the contraction phase for the maximal isometric leg extension for the condition of vibration. A one-way ANOVA revealed no significant (p > 0.05) differences between the vibration and no-vibration conditions for peak normalized EMG_RMS (84.74% Vs 88.1%) values. An ANOVA revealed significant (p > 0.05) differences between the peak fundamental frequencies of the FFT between the conditions vibration (27.1 ± 12.2 Hz) and no-vibration (9.8 ± 3.5 Hz). Peak isometric force, peak rate of force development, rate of force development at times 0.05, 0.01, 0.1, 0.5 seconds, and rate of force development at 50, 75, and 90% of peak force were not significantly different. The results of this study suggest that the application of vibration stimulation at 50 Hz during the contraction does not contribute to muscle activation, or enhance force production for maximal isometric contractions.

Key Points

• The application of a vibratory stimulation to the human body increases the normal acceleration resulting in an increase in force and a change in performance
• This study was to address this issue by examining the effects of a direct superimposed muscle/tendon vibration at 50 Hz on isometric strength characteristics
• No improvement or change in isometric force or rate of force development
• No changes to peak normalized EMG_RMS values

Key words: Strength, oscillations, isometric, peak, muscle activation     

Fatigue performance of angle-stable tibial nail interlocking screws

Purpose

Tibial nail interlocking screw failure often occurs during delayed fracture consolidation or at early weight bearing of nailed unstable fractures, in general when high implant stress could not be reduced by other means. Is there a biomechanical improvement in long-term performance of angle stable locking screws compared to conventional locking screws for distal locking of intramedullary tibial nails?

Methods

Surrogate bones of human tibiae were cut in the distal third and distal locking of the 10 mm intramedullary tibial nail was performed with either two angle stable locking screws or two conventional locking screws in the mediolateral plane. Six specimens per group were mechanically tested under quasi-static and cyclic axial loading with constantly increasing force.

Results

Angle stable locking screw constructs exhibited significantly higher stiffness values (7,809 N/mm ± 647, mean ± SD) than conventional locking screw constructs (6,614 N/mm ± 859, p = 0.025). Angle stable locking screw constructs provided a longer fatigue life, expressed in a significantly higher number of cycles to failure (187,200 ± 18,100) compared to conventional locking screw constructs (128,700 ± 7,000, p = 0.004).

Conclusion

Fatigue performance of locking screws can be ameliorated by the use of angle stable locking screws, being especially important if the nail acts as load carrier and an improved stability during fracture healing is needed.     

Civilian helicopter accidents into water: analysis of 46 cases, 1979-2006

BACKGROUND: When a helicopter crashes or ditches into water the crew and passengers must often make an escape from underwater and a number of the occupants do not survive. This paper examined fatality rates, human factors problems with escape, and causes of death in Canadian civilian registered helicopter accidents in water (1979-2006). METHOD: Data obtained from the Transportation Safety Board of Canada was reviewed. Key issues such as fatalities, injuries, warning time, sinking, and inversion were examined. RESULTS: There were 46 helicopters that ditched into water. There were 124 crew and passengers involved. Of those, 27 (23%) crew and passengers died. Lack of warning time (55%), rapid sinking (72%), and inversion (35%) were the most common issues in the accidents. CONCLUSION: Survival rates for Canadian registered helicopter accidents into water (78%) show little change from previously reported worldwide data. Lack of warning time, rapid sinking, and inversion were the significant factors in the survival rate. The practical implication is that crew and passengers involved in planned flights over water must wear all the life support equipment on strap-in and not have it stowed on the back of the seat or in the cabin.     

Optimal closure of surgical wounds in forefoot surgery: are adhesive strips beneficial?

A subcuticular suture is an ideal closure method of surgical wounds where the aim is healing by primary intention. The addition of adhesive strips over the subcuticular suture appears to be based on anecdotal, rather than experimental evidence. We performed a prospective study to compare the postoperative wound complications of combination closure with subcuticular closure alone. The wounds of 60 consecutive patients undergoing foot surgery were assessed clinically for wound complications at one week postoperatively. Patients who had a combined closure were more likely to develop wound complications. They were also twice as likely to return to clinic for a further wound check. The addition of adhesive strips to such a closure appears to offer no clinical benefit, and can be detrimental to wound healing. We recommend meticulous closure of surgical wounds with continuous, absorbable, subcuticular suture without adhesive strips, for an optimal outcome.     

Chronic oedema: a prevalent health care problem for UK health services

Chronic oedema (CO) is a major clinical problem worldwide, which has many important secondary consequences for health, activity and participation. Effective treatment planning and organisation of services is dependent on an understanding of the condition and its epidemiology. This cross‐sectional study was designed to estimate the point prevalence of CO within the health services of one UK urban population and to determine the proportions that have concurrent leg ulceration. Patients with CO in all anatomic sites were ascertained by health care professionals in one acute and one community hospital, all relevant outpatient and community nursing services, general practices and all nursing/residential homes in one urban catchment area (Derby City). The presence and distribution of oedema was confirmed through a brief clinical examination. A battery of demographic and clinical details was recorded for each case. Within the study population of Derby City residents, 971 patients were identified with CO [estimated crude prevalence 3·93 per 1000, 95% confidence interval (CI) 3·69–4·19]. The prevalence was the highest among those aged 85 or above (28·75 per 1000) and was higher among women (5·37 per 1000) than men (2·48 per 1000). The prevalence among hospital inpatients was 28·5%. Only five (3%) patients in the community population had oedema related to cancer or cancer treatment. Of the 304 patients identified with oedema from the Derby hospitals or community health services, 121 (40%) had a concurrent leg ulcer. Prevalence statistics and current demographic trends indicate that CO is a major and growing health care problem.