Endoscopic pituitary surgery - a. beginner’s guide

Endonasal endoscopic surgery is now the preferred technique to tackle pituitary tumours. Our paper describes the stepwise endoscopic approach for surgeons embarking on pituitary surgery. It also highlights the common pitfalls encountered during surgery and the ways to avoid them. One must proceed in a gradual step- wise manner starting from simple exposure of the sphenoid sinus to complete endoscopic tumour removal so us to gain the neurosurgeon’s confidence as well as develop our own skills, confidence and ability to tackle complications. We use the endonasal paraseptal trans- sphenoidal approach. Surgery begins with gentle packing between the middle turbinate and septum to expose the anterior sphenoid wall and expose the sphenoid astium. The ostitum is then widened inferiorly and onto the opposite side to expose both sphenoid sinuses. The inter- sphenoid sinus and necessary mucosa is removed to expose the sella. We then use a bone flap technique or punches to open the sella. After incising the dura, tumour is removed with a suction curette. An endoscope holder facilitates the operation. The bone flap is replaced at the end of surgery to reconstruct the sella. This is especially important if a CSF leak is present. Nasal packing is usually not required.     

Pharmacological studies on nitro‐naproxen (naproxen‐2‐nitrooxyethylester)

Naproxen‐2‐nitrooxyethylester (S‐(+)‐2‐(6‐methoxy‐2‐naphthyl)propanoic acid‐2‐nitrooxyethylester, LE‐EK06) was synthesized from naproxen and 2‐nitrooxyethylbromide as a novel nitric oxide–releasing derivative of naproxen. Molar equivalents of LE‐EK06 (6.93–27.73 mg/kg, p.o.) to naproxen dose‐dependently exhibited greater antinociceptive activity in comparison to naproxen in a writhing assay. The compound (5.54–22.18 mg/kg, p.o.) showed greater anti‐inflammatory activity at 2 h after as comparable to its effect at 4 h after carrageenan challenge in rats. Further, LE‐EK06 (9.45 mg/kg, p.o.) was more potent in the carrageenan‐evoked hyperalgesia. LE‐EK06 (11.09 mg/kg, p.o.) and naproxen (8.0 mg/kg, p.o.) showed a comparable inhibitory effect on exudate formation and migration of polymorphonuclear leukocytes (PMNs) in a carrageenan‐induced pleurisy test. Further, the compound (11.09 mg/kg, p.o.) significantly reduced myeloperoxidase activity in carrageenan‐treated paw and demonstrated significantly less gastrotoxicity in acute and chronic (21 days) studies. The scanning electron microscopy revealed that LE‐EK06 showed only mild gastric damage (slight disruption of mucus layer) in comparison to naproxen. The present study suggested that naproxen‐2‐nitrooxyethylester (LE‐EK06) represents a novel gastric sparing NSAID. Drug Dev. Res. 61:66–78, 2004. © 2004 Wiley‐Liss, Inc.     

Effect of tertiary multileaf collimator (MLC) on foetal dose during three-dimensional conformal radiation therapy (3DCRT) of a brain tumour during pregnancy.

BACKGROUND AND PURPOSE: The aim of this work was to measure the dose to foetus both in vivo and in vitro during three-dimensional conformal radiation therapy (3DCRT) in a pregnant patient with a pituitary adenoma. The study was then extended to assess the components contributing to the foetal dose such as collimator scatter, internal scatter, head leakage, wedge scatter and multileaf collimator (MLC) effect. PATIENTS AND METHODS: A 30-year-old pregnant woman with a non-functioning pituitary macroadenoma was planned for 3DCRT with 6MV X-ray using four equally weighted MLC-shaped non-coplanar wedged portals. In vivo dosimetry was carried out using thermoluminescent (TL) phosphor powder, which was placed at different positions on the patient, corresponding to different locations in the uterus and also at external os. In vitro measurements were also performed on a simulated phantom using the same set-up parameters and beam arrangement to verify the in vivo measured dose. Experiments were carried out to measure the respective contributions of different components towards peripheral dose. RESULTS: In vitro measured dose to foetus was found to be slightly more than that of in vivo measurement with a maximum of 0.044% of the prescribed dose of 45Gy, which corresponded to 0.0199+/-0.0008Gy. Thermoluminescence dosimeter (TLD) kept at the external os of the patient showed a dose of 0.031% of the prescribed dose. Among the various components of the peripheral dose (foetal dose) measured, head leakage was found to be the leading cause contributing 52%, followed by wedge scatter (31%), collimator scatter (14%) and internal scatter (13%). The use of MLC reduced not only the volume of normal brain irradiation as compared to open fields but also the peripheral dose by 10%. CONCLUSION: Radiotherapy of brain tumours during pregnancy poses a unique clinical situation and decisions to deliver radiotherapy should be taken after detailed in vitro and in vivo dosimetric measurements. Our findings suggest that the beam arrangement using 3-4-fields generally used for 3DCRT of brain tumour with MLC for optimal coverage can be employed for pregnant patients even in early trimester. A possible increase in foetal dose from wedges to a large extent can be compensated with the use of MLC.     

The Effect of Antifibrinolytic Prophylaxis on Postoperative Outcomes in Patients Undergoing Cardiac Operations

Antifibrinolytic agents such as aprotinin and epsilon aminocaproic acid limit postoperative bleeding and blood transfusion in patients undergoing cardiac operations using cardiopulmonary bypass (CPB). Recent evidence suggests that these agents have adverse side effects that influence operative mortality and morbidity. We studied postoperative bleeding, transfusion rates, and operative outcomes in our patients in order to assess the efficacy of these agents during cardiac operations requiring CPB. We reviewed records of 520 patients undergoing a variety of cardiac operations between January 2005 and May 2009. We measured multiple variables including pre-operative risk factors, antifibrinolytic agent used, and outcomes of operation, such as measures of bleeding and blood transfusion, as well as serious operative morbidity and mortality. Postoperative bleeding rates varied significantly between patients receiving aprotinin and those receiving aminocaproic acid (P < 0.05). There was an associated 12% decrease in operative site bleeding in aprotinin-treated patients compared with aminocaproic acid. There was no significant difference in the transfusion rates of packed red blood cells between patients receiving aminocaproic acid or aprotinin (P > 0.05), though individuals in the aprotinin group did receive FFP more frequently than patients in the aminocaproic acid group (P < 0.05). There was no significant difference in morbidity and mortality rates between patients in either drug group (P > 0.05). Our study shows that aprotinin is more effective at controlling operative site bleeding than aminocaproic acid. Reduced operative site bleeding did not portend better outcome or differences in transfusion requirements. Aminocaproic acid remains a safe and cost-effective option for antifibrinolytic prophylaxis because of unavailability of aprotinin.     

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.     

Assessment of the efficacy and tolerability of a fixed dose combination of atorvastatin 10 mg + metformin SR 500 mg in diabetic dyslipidaemia in adult Indian patients

Type 2 diabetes mellitus is associated with a marked increase in the risk of coronary heart disease (CHD) or stroke (by a factor of two to three compared with non-diabetic patients), and cardiovascular disease (CVD) accounts for the majority of deaths among patients with diabetes. A new fixed dose combination containing atorvastatin 10 mg + metformin SR 500 mg is being introduced in the Indian market for the treatment of dyslipidaemia in diabetic patients. The present study was therefore undertaken to assess efficacy, safety and tolerability of a fixed dose combination of atorvastatin 10mg + metformin SR 500mg in adult Indian patients with diabetic dyslipidaemia. The final protocol was approved by relevant ethics committee before the initiation of study. Informed consent was obtained from all the patients prior to enrollment in study. The total duration of study was 14 weeks including two weeks dietary run in period. Patients fulfilling the selection criteria received a single oral tablet of fixed dose combination of atorvastatin 10mg + metformin SR 500mg once daily for 12 weeks. The primary efficacy parameters were assessed by evaluating reduction in fasting and postprandial plasma glucose concentration levels at baseline and thereafter at each follow up visit at 2, 4, 8 and 12 weeks and plasma lipid profile and glycosylated Hb levels at baseline and end of study. The secondary efficacy parameters were assessed by evaluating percentage change from baseline at the end of the study (week 12) in the plasma concentration of the various lipid parameters such as total, HDL-, LDL- and very low density (VLDL)-cholesterol, triglycerides, Apo B, Apo A1, TC/LDL ratio, LDL/ HDL ratio, and percentage of patients achieving LDL-cholesterol goals as per NCEP ATP III guidelines. A total of 213 patients were enrolled in the study. Of these seven patients were lost to follow-up and considered as drop-outs. Therapy with the fixed dose combination of atorvastatin 10 mg + metformin SR 500 mg resulted in a significant reduction in the mean plasma fasting and postprandial glucose levels (35 and 38.8% respectively). There was a steep fall in the HbA1c levels from baseline levels of 8.76% to 6.74% (23.1%). There was also a significant (p < 0.05) reduction in mean total cholesterol (31.2%), LDL cholesterol (35.4%), VLDL-cholesterol (19.6%) and a significant increase HDL-cholesterol (9.5%). Thus there appeared to be trend towards reducing atherosclerosis following therapy with the fixed dose combination of atorvastatin 10 mg + metformin SR 500 mg. Mean body mass index was significantly reduced in the patients in the present study following therapy with the study drugs. The fixed dose combination of atorvastatin with metformin was well tolerated with mostly gastro-intestinal adverse events being reported in the current study. Moreover, most of the adverse events were mild to moderate in intensity and disappeared with continued treatment. In conclusion, the results of the present study suggest that, the fixed dose combination of atorvastatin 10 mg + metformin SR 500 mg is efficacious and well tolerated therapeutic modality in patients with diabetic dyslipidaemia. Furthermore this combination offers dosage convenience to the patient and by virtue of its dual mode of action is a useful addition to the therapeutic armamentarium for patients with diabetic dyslipidaemia.     

Infant feeding practices of mothers in an urban area in Nepal.

Background: Child health in developing countries including Nepal is a matter of serious concern as the prevalence of malnutrition among children continues to be high with 48.6% of children under five in Nepal being underweight. Since infant feeding practices adopted by mothers play a major role in influencing health of these children, there is a need to study the infant feeding practices prevalent in different areas in order to have pragmatic approaches to solve this problem. Materials and methods: A cross sectional study was conducted among mothers who attended the immunization clinics of 18 wards of Pokhara municipality area. They were interviewed with a semi-structured questionnaire on various aspects of infant feeding. Result: A total of 168 mothers were interviewed and prevalence of breastfeeding was 99.4% (167). Only 43.5% of the mothers initiated breastfeeding within one hour of birth and 60.5% were practicing exclusive breastfeeding at 5 months. Almost 40% of the mothers started complementary feeding before the recommended age of 6 months and 22.5 % delayed introduction of complementary feeding beyond the recommended age. Conclusion: Breast feeding practices adopted by mothers of Pokhara urban area are still lacking in terms of late initiation of and early starting of complementary feeding. There is a need to educate the mothers regarding proper infant feeding practices. Key words: infant feeding, breastfeeding, weaning.