Comparative evaluation of three methods of endotracheal tube cuff inflation for adequacy of seal.

Background and Aims: Intubation with cuffed endotracheal tube (ETT) is common in operation rooms, critical care, and emergency rooms. The pressure exerted by the cuff on the tracheal mucosa can lead to a reduction in blood flow to the tracheal wall and result in mucosal ischemia. There are many methods for ETT cuff inflation. Aim of the study was to compare the cuff pressures and volumes between the three methods of ETT cuff inflation. Material and Methods: One hundred and twenty patients were randomized into three groups: Group SG (stethescope guided), group AL (audible leak), and group P (palpation). In group SG, the cuff was inflated by auscultating with the bell of the stethoscope over the thyroid cartilage for leak around cuff. In group AL, the cuff was inflated by listening for an audible leak around the cuff with observer's ear 5 cm away from the mouth of the patient. In group P, the cuff was inflated by palpating for a leak over the cricoid and trachea. The adequacy of the cuff seal was compared between the groups by assessing the volumes of additional air needed to stop the leak around the cuff as confirmed by supraglottic capnometry. Results: The initial volumes needed to inflate the cuff were significantly more in the stethoscope (SG) and hearing (AL) groups than in the palpation (P) group (SG = 5.1 ± 1.4 ml, AL = 4.6 ± 1.6 ml, P = 3.1 ± 0.9 ml; SG and AL vs. P, P < 0.001). Additional cuff volumes required to achieve zero leak around cuff by supraglottic capnometry were 0.85 ± 1 ml in group SG, 1.3 ± 1.1 ml in group AL, and 2.237 ± 0.8 ml in group P (SG vs. P and AL vs. P; P < 0.001). Conclusion: Out of the auscultation-guided, audible leak-guided, and palpation-guided methods of ETT cuff inflation, the auscultation-guided and audible leak-guided methods achieve significantly better tracheal seal than the palpation-guided method.

The agreement between arterial and venous lactate in patients with sepsis.

BACKGROUND: Arterial sampling, which is the gold standard for measuring lactate levels in sepsis, is more painful, requires experience and is associated with a higher incidence of morbidity, when compared with venous sampling. This study attempted to measure the correlation and agreement between arterial and peripheral venous (PV) lactate and between arterial and central venous (CV) lactate, with the objective to test interchangeability of the two and possibly support the use of venous lactate levels in resuscitating patients with sepsis. METHODS: Eighty-seven patients admitted to the critical care unit of our hospital with the diagnosis of sepsis or septic shock were included in the study after taking informed consent. The arterial, PV and CV samples were taken within the first 24 hours following admission and within 10 minutes of each other. Lactate levels, CV oxygen saturation (ScvO2 ) and base excess of each sample type were reported within 15 minutes of collection. Patients were followed up for a period of 28 days to record the need for organ support (newly diagnosed renal failure, need for renal replacement therapy [RRT], liver failure, coagulopathy and need for ventilation) and mortality. RESULTS: Pearson correlation for arterial versus PV lactate was 0.76 and for arterial versus CV lactate was 0.992. The mean difference between arterial and PV lactate was found to be -0.30 (95% confidence interval [CI], -0.38 to -0.21). The upper and lower limits of agreement were 0.51 and -1.10, respectively. Mean difference between arterial and CV lactate was found to be -0.13 (95% CI, -0.21 to -0.05). Upper and lower limits of agreement were 0.63 and -0.89, respectively. CONCLUSION: Our study demonstrates a high level of agreement in the lactate levels as measured on venous samples and arterial samples. Venous lactate levels are reliable in resuscitation of patients with sepsis.

A randomised comparison of lidocaine 2% gel and proparacaine 0.5% eye drops in paediatric squint surgery.

We conducted a randomised trial comparing lidocaine 2% gel with proparacaine 0.5% eye drops in children having elective squint surgery. One hundred and forty children aged between 3 and 14 years were recruited. The requirement for intra-operative fentanyl and postoperative ibuprofen was significantly less in the lidocaine group compared with the proparacaine group (1 (1.7%) vs 12 (18.5%), p=0.002 and 16 (27.6%) 38 (58.5%), p=0.001, respectively). The incidence of postoperative nausea and vomiting was significantly less in the lidocaine group compared with the proparacaine group (6 (10.3%) vs 16 (24.6%), p=0.04). There were no differences between the groups in terms of incidence and severity of the oculocardiac reflex. We conclude that, compared with proparacaine 0.5% eye drops, a single application of lidocaine 2% gel improves peri-operative analgesia and reduces the incidence of postoperative nausea and vomiting in elective paediatric squint surgery.

Comparison of medication acceptance of intranasal midazolam administered by parents versus doctors in children - A randomized trial.

BACKGROUND: The positive effects of midazolam as a premedication in pediatric patients are well documented. Although there are many studies regarding the route and dosage of administration, literature does not have any evidence on the outcome of medication acceptance based on the person administering the drug. AIM: The aim of this study was to compare the medication acceptance and preoperative anxiolysis of intranasal midazolam administered by parents and anesthesiologists. MATERIALS AND METHODS: This prospective randomized study was conducted in sixty children belonging to the American Society of Anesthesiologists Class 1 or 2 belonging to either sex, aged between 1 and 9 years, undergoing elective surgeries. Group P received intranasal midazolam administered by parents, whereas Group D received intranasal midazolam administered by doctors. Various scores were assessed. RESULTS: Children were more sedated in Group P. Clinically, medication acceptance was better in Group P when compared with Group D, but a statistically significant difference in medication acceptance was seen only in patients who are >4 years of age. Parental separation, Ramsay Sedation Score, and mask acceptance were better in Group P than in Group D. CONCLUSION: Intranasal midazolam when given by parents produces better preoperative anxiolysis and easier parental separation as compared with administration by a medical staff.

Comparison of weight-based and pinna size-based selection of ProSeal laryngeal mask airway in paediatric population - A prospective exploratory trial.

BACKGROUND AND AIMS: Weight-based selection of ProSeal laryngeal mask airway (PLMA) size may be unreliable in some situations. The aim of this study was to compare the ventilation parameters using PLMA during controlled ventilation between weight-based size selection and pinna size-based selection in children. METHODS: A total of 204 patients were randomised to receive either pinna size-based (Group P) or weight-based (Group W) size selection of PLMA. We tested the hypothesis that pinna size-based selection of PLMA was better than weight-based selection of PLMA in paediatric patients during controlled ventilation under general anaesthesia in terms of oropharyngeal sealing pressure (the primary end-point) and Brimacombe score. Cuff pressure was maintained at 60 cm of H2O during the study. Secondary outcomes included the number of attempts for successful placement of PLMA, peak airway pressure, gastric tube placement, traumatic insertion, and complications were also compared. Parametric variables were analysed using unpaired t-test and categorical variables were analysed using Mann-Whitney and Chi-square test. RESULTS: In all, 200 patients were analysed. The mean oropharyngeal sealing pressure in Group P was 25.4 ± 3.5 cmH2O and 24.9 ± 3.8 cmH2O in Group W, (P = 0.34). There was no significant difference between the two groups in any of the secondary outcomes. There were no traumatic insertion or complications reported in both the groups. CONCLUSION: Pinna-based size selection method can be used in PLMA placement in the paediatric population for positive pressure ventilation and it serves as an alternative method to weight-based selection.

Comparison of analgesic efficacy of continuous bilateral transversus abdominis plane catheter infusion with that of lumbar epidural for postoperative analgesia in patients undergoing lower abdominal surgeries.

BACKGROUND AND AIMS: Epidural analgesia (EA) and transversus abdominal plane (TAP) block have been part of multimodal analgesia techniques for postoperative pain relief in abdominal surgeries though EA has been established as gold standard. This study assesses and compares the analgesic efficacy of continuous bilateral TAP catheter infusion and lumbar epidural infusion. METHODS: In this randomised, single-blind, prospective, non-inferiority trial, 75 patients were randomised to receive a bolus dose of 15 ml, 0.25% bupivacaine followed by an infusion of 5-12 ml/h of 0.125% bupivacaine via lumbar epidural in EA group and a bolus dose of 0.4 ml/kg of 0.25% bupivacaine bilaterally via TAP catheter followed by continuous infusion at 5ml/h of 0.125% bupivacaine in TAP group postoperatively. VAS scores (primary objective) and sensory dermatome blockade were recorded at 1, 4, 8, 12 and 24 h. Total morphine consumption, PONV, incidence of hypotension and patient satisfaction scales were recorded at the end of 24 hours. RESULTS: The median VAS scores were comparable between the groups at 1, 4, 8, 12 and 24 hours both at rest (P = 0.11, 0.649, 0.615, 0.280 and 0.191, respectively) and on coughing (p = 0.171, 0.224, 0.207, 0.142 and 0.158, respectively). Total morphine consumption in 24 h between TAP and EA group was comparable (p = 0.366). There was no statistical difference in the incidence of hypotension, PONV and patient satisfaction scale. CONCLUSION: Continuous bilateral TAP block is as efficacious as the continuous lumbar epidural infusion in relieving postoperative pain in patients undergoing lower abdominal surgeries.

Comparison of caudal epidural block with paravertebral block for renal surgeries in pediatric patients: A prospective randomised, blinded clinical trial.

STUDY OBJECTIVE: This study was undertaken to compare the analgesic efficacy of ultrasound-guided single-shot caudal block with ultrasound-guided single-shot paravertebral block in children undergoing renal surgeries. DESIGN: Randomised, interventional, blinded clinical trial. SETTING: Operating rooms of All India Institute of Medical Sciences, New Delhi, India. PATIENTS: 50 children aged 2-10 years, of ASA status I/II, posted for elective renal surgeries. INTERVENTIONS: The children were randomised into two groups (Group C-caudal block, Group P-paravertebral block). After induction of general anesthesia, single-shot caudal or paravertebral block was performed under ultrasound guidance, with 0.2% ropivacaine with 1:200000 adrenaline. MEASUREMENTS: Time to first rescue analgesia, time to perform blocks, intraoperative and post-operative hemodynamics, post-operative FLACC scores, incidence of complications, parental satisfaction scores were recorded. MAIN RESULTS: Children in Group P had significantly longer duration of analgesia (p < 0.0004) than Group C. Post-operative FLACC scores (p < 0.005) and analgesic requirements (p < 0.0004) were lower in Group P. The mean fentanyl requirement over 24 h in group P was 0.56 ±â€¯0.82 µg/kg, compared to 1.8 ±â€¯1.2 µg/kg in group C. Parents in Group P reported greater satisfaction (p < 0.02). No complications were seen in either of the groups. CONCLUSION: This study showed superior analgesia and parental satisfaction with single-shot paravertebral block in comparison to single-shot caudal block for renal surgeries in children. However, the block performance in children requires adequate expertise and practice.

Standards of care for procedural sedation: Focus on differing perceptions among societies.

Adherence to established standards of care is important for anaesthesiologists to avoid undesirable legal consequences of their actions. The judiciary lays stress on the need to perpetuate healthy doctor-patient correspondence, good documentation, and to bestow a justifiable standard of care. But what defines standard of care and who delineates such standards is something that lacks clarity. The American Society for Gastrointestinal Endoscopy (ASGE) has recently released updated guidelines on the use of sedation and anaesthesia for gastrointestinal endoscopic procedures. Almost simultaneously, the American Society of Anesthesiologists (ASA) has brought out practice guidelines for moderate sedation and analgesia. In contrast to the ASA recommendations, ASGE does not view capnography as an essential monitoring modality for endoscopic procedures with moderate sedation because it has apparently not been shown to improve patient safety. However, they do agree that evidence supports its deployment during deep sedation. These differences in views between guidelines published by societies of substantial academic and clinical standing can confuse the agreement over what constitutes standard of care for the particular speciality. It is the expectation that guidelines and consensus statements in anaesthesiology be preferably issued by national or international organizations of the same speciality.

Importance of Sonography for Guiding Central Venous Cannulation in Patients with Neurofibromatosis.

A 15-year-old boy with neurofibromatosis type 1 (NF1) was referred to us for central venous catheter insertion, and on ultrasound of the neck, he was found to have extensive involvement of the brachial plexus due to the nerve sheath tumour. Multiple hypoechogenic lesions resembling the internal jugular vein and internal carotid artery were visualised and could be differentiated from the vessels by Doppler ultrasound. The importance of analyzing sonographic images of nerve sheath tumours, which can mimic blood vessels, and the importance of Doppler ultrasound for guiding central venous catheters in such patients to avoid nerve injury are discussed in this case report.

Effect of dexmedetomidine as an adjuvant to bupivacaine in femoral nerve block for perioperative analgesia in patients undergoing total knee replacement arthroplasty: A dose-response study.

CONTEXT: Dexmedetomidine is being increasingly used in nerve blocks. However, there are only a few dose determination studies. AIMS: To compare two doses of dexmedetomidine, in femoral nerve block, for postoperative analgesia after total knee arthroplasty (TKA). SETTINGS AND DESIGN: A prospective, randomized, controlled trial was conducted in the Department of Anesthesia at AIIMS, a Tertiary Care Hospital. MATERIALS AND METHODS: Sixty American Society of Anesthesiologists I-II patients undergoing TKA under subarachnoid block were randomized to three Groups A, B, and C. Control Group A received 20 ml (0.25%) of bupivacaine in femoral nerve block. Groups B and C received 1 and 2 µg/kg dexmedetomidine along with bupivacaine for the block, respectively. Outcomes measured were analgesic efficacy measured in terms of visual analog scale (VAS) score at rest and passive motion, duration of postoperative analgesia, and postoperative morphine consumption. Adverse effects of dexmedetomidine were also studied. STATISTICAL ANALYSIS USED: All qualitative data were analyzed using Chi-square test and VAS scores using Kruskal-Wallis test. Comparison of patient-controlled analgesia (PCA) morphine consumption and time to first use of PCA were done using ANOVA followed by Least Significant Difference test. A P < 0.05 was considered statistically significant. RESULTS: The VAS score at rest was significantly lower in Group C compared to Groups A and B (P < 0.05). There was no difference in VAS score at motion between Groups B and C. The mean duration of analgesia was significantly longer in Group C (6.66 h) compared to Groups A (4.55 h) and B (5.70 h). Postoperative mean morphine consumption was significantly lower in Group C (22.85 mg) compared to Group A (32.15 mg) but was comparable to Group B (27.05 mg). There was no significant difference in adverse effects between the groups. CONCLUSION: The use of dexmedetomidine at 2 µg/kg dose in femoral nerve block is superior to 1 µg/kg for providing analgesia after TKA, although its role in facilitating early ambulation needs further evaluation.

Clinical outcome and regression patterns of retinoblastoma treated with systemic chemoreduction and focal therapy: A prospective study.

PURPOSE: To prospectively study the clinical outcome and regression patterns of early retinoblastoma (Groups A and B) after systemic chemotherapy and focal consolidation in Indian children. MATERIALS AND METHODS: Group A eyes were treated with focal therapy (transpupillary thermotherapy/cryotherapy) and Group B with systemic chemoreduction and focal therapy. Outcome measures were efficacy and safety of treatment, risk factors for treatment failure, regression patterns, and factors predictive of regression patterns. RESULTS: Of 119 eyes (216 tumors), 14 (11.8%) were Group A and 105 (88.2%) were Group B eyes. The mean follow-up was 22.6 months. Tumor control was achieved in 111/119 eyes (93.3% overall, 100% Group A, 92.4% Group B). Eight Group B eyes (6.7%) had treatment failure. No serious systemic side-effects were noted. Risk factors for failure included larger tumors (P = 0.001) and proximity to posterior pole (P = 0.014). Regression patterns were Type 4 (50.2%), Type 3 (31.7%), Type 1 (11.1%), and Type 2 (7%). Factors predictive of Type 4 regression were smaller tumors, anterior location, younger age; Type 3 regression was associated with larger tumors, macular location, and older age. CONCLUSIONS: Systemic chemoreduction and focal therapy provided effective tumor control in Indian children. Factors predictive of regression patterns included age, tumor size and its location, and the modality of treatment.

Analgesic and urodynamic effects of epidural meperidine and pentazocine--a comparative study.

Meperidine 1 mg kg-1 and pentazocine 0.3 mg kg-1 were administered epidurally to investigate their effect on vesical function in twenty American Society of Anesthesiologists Classification I (ASA-1) adult males. Cystometry was performed before and 45 minutes following epidural administration of meperidine and pentazocine. There was no significant change in maximum cystometric capacity, detrusor pressure at which detrusor reflex occurred and in vesical compliance following epidural administration of meperidine in ten patients and also in ten patients who received epidural pentazocine. The mean onset of analgesia after epidural administration of meperidine was 8 minutes which lasted for more than 360 minutes whereas mean onset of analgesia after epidural administration of pentazocine was 4 minutes which lasted for more than 360 minutes. There was no significant change in heart rate, blood pressure and respiratory rate after epidural administration of either meperidine or pentazocine. None of the subjects in either of the groups experienced any difficulty in passing urine, frequency or urgency of micturition. Side-effects like nausea, vomiting, pruritus and respiratory depression were not observed. It is concluded that epidural administration of meperidine 1 mg kg-1 or pentazocine 0.3 mg kg-1 produces significant analgesia of faster onset without altering vesical function as documented, both subjectively by voiding symptoms and objectively by cystometry.

Anesthetic management of a parturient with cerebellopontine-angle meningioma.

Cerebellopontine-angle meningioma is a rare intracranial neoplasm. It presents a difficult problem in pregnancy. A 27-year-old multigravida presented with headache, vomiting and visual disturbances at 30 weeks' gestation and cerebellopontine angle meningioma and hydrocephalus were diagnosed. A ventriculoperitoneal shunt was placed under general anesthesia to reduce the symptoms of raised intracranial pressure and to prevent the risk of cerebellar herniation. At 32 weeks a cesarean section was performed under general anesthesia and a healthy baby delivered. A smooth induction and maintenance of anesthesia along with lidocaine and mannitol were used to prevent a rise in intracranial pressure. The intraoperative and postoperative course was uneventful. Thus, immediate neurosurgical decompression improved the patient's condition, and allowed time for fetal maturity and uneventful delivery by cesarean section under general anesthesia.

Microalbuminuria and low hemoglobin as risk factors for the occurrence and increasing severity of diabetic retinopathy.

AIM: To assess the influence of urinary microalbuminuria and hemoglobin concentration on the occurrence and severity of diabetic retinopathy (DR), clinically significant macular edema (CSME) and hard exudate formation. MATERIALS AND METHODS: In this prospective cross-sectional study carried out over a period of 2 years, type 2 diabetic patients seeking ocular evaluation for DR were assessed for presence and severity of DR, presence of hard exudates and CSME. Retinal findings were correlated to severity of microalbuminuria, hemoglobin concentration and other systemic risk factors using linear regression analysis. RESULTS: Three hundred and six patients were included in the study. DR of any grade was seen in 132 (43%) patients, hard exudate formation in 93/306 (30.4%) patients, CSME in 50/306 (16.3%) patients and proliferative DR in 26/306 (8.5%) patients. Duration of diabetes (P < 0.001), microalbuminuria (P < 0.001) and low hemoglobin (P = 0.001) were found to be highly significant risk factors for the development and increasing severity of DR as well as for CSME and hard exudate formation. CONCLUSION: Microalbuminuria and low hemoglobin are strong predictors for DR, CSME and hard exudate formation in type 2 diabetics even after correcting for duration of diabetes and other systemic risk factors. Although not directly involved in the pathogenesis, microalbuminuria can help in identifying patients at risk for more severe diabetic eye disease. Microalbuminuria warrants intensive monitoring of both retinal and renal status. The hemoglobin levels should be monitored regularly in diabetic patients to detect and treat anemia, thereby reducing one risk factor for DR.

Structure of hollow polystyrene microspheres: an SEM study.

Hollow polystyrene microspheres have been prepared by a modified interfacial polymer deposition technique. The hollow microspheres were characterized using scanning electron microscopy. The effects of polymer concentration and the quantity of the internal phase material (methanol) used on the microsphere size and their wall thickness were studied. Increase in polymer concentration causes increase in wall thickness while increasing internal phase material increases microsphere size and deforms them from a spherical shape.

A patient with congenital complete heart block undergoing multiple exposures to general anaesthesia.

We present a patient with congenital complete heart block who underwent multiple anaesthetic exposures for eye examination and bilateral cataract surgery. The diagnosis was made during the first general anaesthetic. Various complications encountered during the multiple exposures are discussed.

Effect of epidural morphine on minimum alveolar concentration of isoflurane in humans.

BACKGROUND AND AIMS: The anaesthetic potency of volatile anaesthetic agents is measured by the minimum alveolar concentration (MAC) required to suppress response in 50% of subjects. We studied the effect of epidural morphine on MAC of isoflurane in humans. SETTINGS AND DESIGN: A prospective single-blind study designed to study the effect of epidural morphine on MAC of isoflurane. SUBJECTS AND METHODS: Forty-eight patients were randomly divided into two groups - Group I patients received 3 mg morphine in 10 ml saline, and Group II patients received 10 ml saline epidurally. Anaesthesia was induced with isoflurane in oxygen and nitrous oxide. Later nitrous oxide was discontinued and MAC of isoflurane determined using modified Dixon's method of sequential sampling. RESULTS: Epidural morphine resulted in a significant reduction in MAC of isoflurane, 0.98 vs. 1.14 in control group (p<0.05). CONCLUSIONS: Epidural administration of 3 mg morphine in 10 ml saline decreased the MAC of isoflurane.