Rashmi Salhotra

Tourniquets in orthopedic surgery

Tourniquets are commonly used in limb surgeries, be it orthopedic or plastic surgeries. But the inflation pressures, the duration, and release guidelines are still not clear. According to a survey, majority of orthopedic surgeons inflate the tourniquet to fixed pressures for the upper and the lower limbs without considering the baseline blood pressure of the patient on whom the tourniquets are being applied. This review was designed to recall and review the safe use of tourniquets and the various techniques that can be employed to minimize the complications of tourniquet use. Google, science direct, and pubmed were searched for appropriate literature and relevant articles were identified.

Subarachnoid block for caesarean section in severe preeclampsia

Pregnancy-induced hypertension constitutes a major cause of morbidity and mortality in developing nations and it complicates about 6–8% of pregnancies. Severe preeclampsia poses a dilemma for the anesthesiologist especially in emergency situations where caesarean deliveries are planned for uninvestigated or partially investigated parturients. This article is aimed to review the literature with regards to the type of anesthesia for such situations. A thorough search of literature was conducted on PubMed, EMBASE, and Google to retrieve the articles. Studies on parturients with severe preeclampsia, undergoing caesarean section, were included in this article. There is growing evidence to support the use of subarachnoid block in such situations when the platelet counts are >80,000 mm-3. Better hemodynamic stability with the use of low-dose local anesthetic along with additives and better neonatal outcomes has been found with the use of subarachnoid block when compared to general anesthesia.

ED50 of hyperbaric bupivacaine with fentanyl for cesarean delivery under combined spinal epidural in normotensive and preeclamptic patients.

Background and Objectives The use of reduced intrathecal doses is advised for spinal anesthesia during cesarean delivery. However, there are inadequate data regarding the minimum effective dose of intrathecal bupivacaine for cesarean delivery. Preeclampsia is caused by an endothelial dysfunction leading to generalized vasoconstriction. Whether this can offset the pregnancy-induced decrease in intrathecal dose requirement caused by epidural venous dilation and consequent thecal compression is not known. There are no data to evaluate the minimum effective dose of intrathecal drug for cesarean delivery in preeclamptic patients. This study aimed to determine the minimum effective dose represented by the ED50 of intrathecal hyperbaric bupivacaine for normotensive and severely preeclamptic patients undergoing elective cesarean delivery. Methods Combined spinal epidural anesthesia was administered using a standardized technique on 18 consecutively preeclamptic and normotensive patients, each carrying an otherwise uncomplicated singleton pregnancy. The dose of intrathecal hyperbaric bupivacaine was decided by using the up-and-down method with an initial dose of 9 mg and dosing change of 1 mg. All patients received 20 &mgr;g of fentanyl intrathecally with bupivacaine. A successful block was defined as one that resulted in a sensory block to T4 level with modified Bromage score of 1 or 2 within 15 minutes of intrathecal injection. Results ED50 of intrathecal hyperbaric bupivacaine was identical in severely preeclamptic and normotensive parturients undergoing elective cesarean delivery (4.7 mg; 95% confidence interval, 4.5–4.9 mg). Conclusions When a combined-spinal epidural is planned in normotensive or severely preeclamptic patients for an elective cesarean delivery, the ED50 of intrathecal hyperbaric bupivacaine along with 20 &mgr;g of fentanyl is 4.7 mg.

Is midazolam superior to triclofos and hydroxyzine as premedicant in children

Background: Search for an ideal premedicant drug for children is still on. A prospective, randomized trial was conducted to compare the efficacy of midazolam, triclofos and hydroxyzine as premedication in children undergoing lower abdominal surgeries. Materials and Methods: Sixty American Society of Anesthesiologists I or II patients 2-8 years of age, scheduled for elective lower abdominal surgery were included. The patients were randomly divided into three groups M, T and H of 20 children each who received midazolam 0.5 mg/kg, triclofos 75 mg/kg and hydroxyzine 0.5 mg/kg respectively, orally 60 min before surgery. The acceptability of drugs, level of sedation, anxiety during separation and on mask application was assessed. Results: The acceptability of midazolam and hydroxyzine was better than triclofos. Hydroxyzine was found to have lesser sedative effect as compared to both midazolam and triclofos. No major adverse effects were observed. Conclusion: Midazolam was found to be a better premedicant in terms of sedation, anxiolysis and safety.

Minimum effective volume of normal saline for epidural volume extension

Background: Rescue strategies like changes in tilt of table are used to raise the level of an inadequate sensory block following intrathecal injection. Epidural volume extension (EVE) refers to an injection of normal saline through epidural catheter following an intrathecal block. It results in a rapid increase in the sensory level of subarachnoid block. Thus, it has been postulated that EVE may be used as a rescue strategy for an inadequate post-spinal sensory block. However, the minimum effective volume (MEV) of normal saline for EVE induced increase in level of spinal block has not been researched till date. We proposed to determine the MEV of normal saline required for EVE induced increase in post-spinal block sensory level. Materials and Methods: This prospective sequential allocation study was conducted in consenting adult males after institutional ethical committee approval scheduled for lower limb surgery under combined spinal epidural (CSE) anesthesia, who had an inadequate level of sensory block. Herein, an inadequate level was defined as lower than T10 at 10 min after the intrathecal injection, with no ascent for two consecutive readings taken 2 min apart. The EVE was performed with normal saline injected through epidural catheter, and was considered successful if the level of sensory block increased by two or more dermatomal segments within 5 min of the injection. The volume of normal saline for EVE was decided by using the up-and-down method, with the first patient receiving 10 mL and a dosing interval of 1 mL in subsequent patients. The analysis was done using the formula of Dixon and Massey, which enabled calculation of the MEV with 95% CI. Quantitative parametric data is represented as mean ± SD and nonparametric data as median (range). Results and Conclusion: The MEV of normal saline to raise the level of sensory block by two or more dermatomal segments within 5 min of EVE is 7.4 mL (95% CI: 5.5-9.9 mL).

An unanticipated difficult airway in Lesch-Nyhan syndrome

An 11-year-old boy with Lesch–Nyhan syndrome presented to the emergency for fixation of a fractured femur. During induction of general anesthesia, unexpected difficult intubation was encountered with a 6.5-mm ID endotracheal tube and successively smaller tubes, also failing to pass 1 cm beyond the vocal cords. Intubation was finally achieved with a 4.5-mm ID tube. The surgery was completed uneventfully. A tracheal diverticulum was found in the computerized tomography (CT) scan performed postoperatively to account for this unexpected difficult intubation. This case highlights the anesthetic concerns in Lesch-Nyhan syndrome and also reports the rare occurrence of a tracheal diverticulum associated with it.

Intrathecal ropivacaine with or without tramadol for lower limb orthopedic surgeries

Background and Aim: Preservative free tramadol has been used as an adjuvant to intrathecal bupivacaine. However, the effect of the addition of tramadol on intrathecal isobaric ropivacaine has never been studied. Material and Methods: This prospective, randomized, double-blind study was conducted in 50 adult male American Society of Anesthesiologists grade I or II patients, aged 18–60 years, being operated for unilateral femur fractures. An epidural catheter was inserted in L2-L3 interspace and subarachnoid block was given in L3-L4 space. The patients were randomized to receive 0.5 mL normal saline (group R) or 0.5 mL (25 mg) preservative free tramadol (group RT) with 2.5 mL of 0.75% intrathecal ropivacaine. Hemodynamic parameters, sensory level, motor block, sedation and side-effects were recorded. Statistical analysis was done using Students t-test, Chi-square test, Fischers exact test and repeated measures ANOVA. Results: The time of sensory block onset was 9.2 ± 4.9 min and 8.6 ± 5.3 min (P = 0.714) in group R and group RT, respectively. The motor block onset was also comparable in both the groups (P = 0.112). The duration of sensory block was 147.2 ± 37.4 min in group R and 160.4 ± 40.9 min in group RT (P = 0.252). The median maximum block height achieved in both the groups was T6 and the time to achieve the maximum block was also comparable statistically (P = 0.301). Conclusion: The addition of intrathecal tramadol 25 mg to the isobaric ropivacaine does not alter the block characteristics produced by intrathecal ropivacaine alone.