Abnormal renal vasodilation to an amino acid infusion in congestive heart failure: normalization by enalapril

In congestive heart failure (CHF), the neurohormonal mechanisms that cause renal vasoconstriction, particularly those depending on the renin-angiotensin system, could interfere with renal vasodilating mechanisms. To elucidate this issue, we studied the kidney response to an amino acid infusion (known to cause renal vasodilation in healthy individuals) in eight patients with CHF. We found that the amino acid infusion (0.7 mL/kg/h of a 10% solution) elicited no renal hemodynamic response, in marked contrast to healthy subjects. We next hypothesized that the renin-angiotensin system (known to be activated in heart failure) has a role in the lack of response to the amino acid infusion. To test this hypothesis, we repeated the study after two 5-mg doses of enalapril, an inhibitor of the angiotensin-converting enzyme, administered 12 hours apart. After enalapril treatment, the amino acid infusion caused a 45% increase in mean renal blood flow (RBF) from 383 +/- 55 to 557 +/- 51 mL/min at the fifth hour (P < 0.05). This normalization of the renal response to the amino acid infusion occurred without changes in cardiac output or in systemic vascular resistance. Hence, the renal fraction of the cardiac output increased during the amino acid infusion. The recovery of the renal vascular response was not accompanied by an increase in glomerular filtration rate (GFR; filtration fraction decreased), suggesting a predominant efferent arteriole dilatation. Our study shows that, in heart failure, the kidney loses its ability to increase RBF in response to an amino acid load. This lack of renal vascular response can be restored by inhibiting the renin-angiotensin system and is unrelated to changes in systemic hemodynamics.     

Unreamed interlocking nailing in open fractures of tibia

PURPOSE: To assess the clinical outcome of unreamed intramedullary interlocking nailing in open fractures of tibia, and to evaluate the incidence of complications in these open fractures as a result of the unreamed intramedullary nailing. METHODS: Between June 1999 and May 2000, a total of 60 cases of open tibial shaft fractures were operated on with unreamed interlocking nails at Safdarjung Hospital, New Delhi, India. Records of 56 patients (4 women and 52 men) were available for study. Only injuries associated with the tibial shaft were included. Traffic accidents were the cause of fractures in all patients. All fractures were classified according to Gustilo and Anderson system for open fractures. There were 30 (53.6%) type-I, 18 (32.1%) type-II, 4 (7.1%) type-IIIA, and 4 (7.1%) type-IIIB fractures. After thorough debridement under anaesthesia, an unreamed interlocking nail was inserted with assistance by an image intensifier. All nails were statically locked with one screw each proximally and distally. RESULTS: The patients were followed up for a mean period of 20 months (range, 18-24 months) and were evaluated according to the modified Ketenjian's criteria. Results were good to excellent in 85.8% cases, and poor in 10.7% cases. Only 2 of 8 patients with type-III fractures had good results. Two of 4 type-IIIA and all 4 type-IIIB fractures had chronic osteomyelitis. Of 56 patients, 6 had early infection, 6 had delayed union, 6 had infected non-union, 2 had nail breakage, 8 had screw breakage, and 10 had anterior knee pain. CONCLUSION: Unreamed interlocking tibial nailing can be safely used for type-I and type-II open injuries even with delayed presentation. Use of unreamed nailing in those type-III fractures with delayed presentation was not recommended, because of high incidence of complications.     

Rhabdomyolysis with acute kidney injury in deceased donors is not a contraindication for kidney donation

Purpose

Deceased patients with acute kidney injury (AKI) from rhabdomyolysis can be considered as potential kidney donors.

Methods

We performed a retrospective chart review from January 2005 to January 2011 of three donors with AKI from rhabdomyolysis and the four recipients of the donated kidneys. Three donors had AKI from rhabdomyolysis as evidenced by elevated serum creatinine levels, myoglobinuria, and plasma creatinine kinase levels greater than five times the upper limit of normal. All grafts were maintained on pulsatile machine perfusion (MP) prior to transplantation. In one of the patients, serial venous perfusate myoglobin levels were measured from the donor kidney while on MP.

Results

Three of the four recipients had delayed graft function, but all had normalized creatinine function after 1?month. One recipient had a creatinine of 1.2 after 79?months, the longest documented follow-up of this kind. Although we measured venous perfusate myoglobin levels from one of the grafts, we found the levels to decrease with increasing time spent on MP.

Conclusion

Potential donors with AKI secondary to rhabdomyolysis should not be restricted from the donor pool. MP may play a role in minimizing the effects of AKI in these types of donors.     

Airway management in adult patients with deep neck infections: a case series and review of the literature

Patients with deep neck infections, especially those with Ludwig's angina, may die as a result of airway management mishaps. Skillful airway management is critical, but a safe method of airway control in these patients is yet to be established. We subjected patients with deep neck infections to fiberoptic tracheal intubation by using topical anesthesia to provide general anesthesia for surgical interventions. Patient characteristics and techniques for intubations were recorded on a special data-collection form. Of the 26 patients, 17 had Ludwig's angina, and 9 had other types of deep neck infections. Three patients were tracheally intubated while in the sitting position, 2 in Fowler's position, and 21 in the supine position with the head up 10 degrees-15 degrees. Tracheal intubations were successful in 25 patients: 19 nasally and 6 orally. After surgery, seven patients were kept tracheally intubated, and five patients had tracheostomies. Complications were limited to three cases of mild epistaxis and four oversedations with transient hypoxemia. Twelve patients remembered part of the procedure, and two considered it unpleasant. Tracheal intubation with a flexible bronchoscope by using topical anesthesia is highly successful in adult patients with deep neck infections. Tracheostomy using local anesthesia is recommended if fiberoptic intubation is not feasible, if the clinician is not skillful in the use of awake fiberoptic intubation, or if intubation attempts have failed.     

Umbilical hernia repair in cirrhotic patients: utility of temporary peritoneal dialysis catheter

Umbilical herniorrhaphy in cirrhotic patients with ascites is associated with a significant morbidity, recurrence rate, and mortality and therefore is often managed expectantly. Operative repair is indicated if an ascites leak or infection develops. Surgeons must consider the management of postoperative ascites to reduce recurrence rates and complications. We present a unique method using temporary peritoneal dialysis catheter placement (PD). Eight patients with moderate to massive ascites underwent umbilical herniorrhaphy with concomitant peritoneal dialysis placement. Patients have been followed for 8 to 30 months. All patients had successful repair of their hernia with 1 recurrence at 6 months and 1 late death (14 months). Patients were able to effectively control ascites using the PD catheter at home. There were no postoperative infections. The placement of a temporary PD catheter during umbilical herniorrhaphy provides a method for effective control of ascites in patients with cirrhosis. The technique has several advantages including outpatient management during the postoperative period and for easy removal of the catheter when no longer needed.     

General anaesthesia vs. conscious sedation for transfemoral aortic valve implantation: a single UK centre before‐and‐after study

Reported data suggest that 99% of transfemoral, transcatheter aortic valve implantations in the UK are performed under general anaesthesia. This before‐and‐after study is the first UK comparison of conscious sedation vs. general anaesthesia for this procedure. Patients who underwent general anaesthesia received tracheal intubation, positive pressure ventilation, radial arterial and central venous access and urinary catheterisation. Anaesthesia was maintained with propofol or sevoflurane. Patients who received conscious sedation had a fascia iliaca and ilioinguinal nerve block and low‐dose remifentanil infusion, without invasive monitoring or urinary catheterisation. Recruitment took place between August 2012 and July 2015, with a 6‐month crossover period between November 2013 and June 2014. A total of 88 patients were analysed, evenly divided between the two groups. Patients receiving conscious sedation had a shorter anaesthetic time (mean (SD) 121 (28) min vs. 145 (41) min; p < 0.001) and recovery room time (110 (50) min vs. 155 (48) min; p = 0.001), lower requirement for inotropes (4.6% vs 81.8%; OR (95% CI) 0.1 (0.002–0.050); p < 0.001) and a lower incidence of malignant dysrhythmia (0% vs 11.4%; p = 0.020). Conscious sedation appears a feasible alternative to general anaesthesia for this procedure and is associated with a reduced requirement for inotropic support and improved efficiency.