Clinical utility of epidural volume extension following reduced intrathecal doses: a randomized controlled trial.

BACKGROUND AND OBJECTIVES: Epidural Volume Extension (EVE) involves instillation of normal saline into the epidural space soon after an intrathecal injection, with the aim to augment the sensory block height. Its clinical relevance lies in the possibility of using reduced intrathecal dose and yet achieving the desired sensory block level. Intrathecal dose is a known determinant of the level of sensory block. Whether EVE is dependent on intrathecal dose is not known. METHODS: We conducted a randomized, controlled, double-blind study to compare the maximum sensory level (Smax) achieved with or without application of EVE to two different reduced intrathecal doses. Eighty four adult male patients of ASA status I or II with body weight between 50-70kg and height in the range of 150-180cm, scheduled for orthopedic lower limb surgery using combined spinal epidural anesthesia were randomized to receive, either intrathecal dose (5 or 8mg) with or without EVE, in accordance to group allocation. RESULTS: Smax was lowered by application of EVE to 5mg intrathecal bupivacaine (T8.9±4.3 vs. T6.4±1.9 with and without EVE respectively; p = 0.030). Smax was similar when EVE was applied to 8mg intrathecal bupivacaine than without it (T5.8±1.8 vs. T6.4±2.2 respectively; p= 0.324). CONCLUSION: EVE should not be applied to 5mg plain bupivacaine during a combined spinal epidural block in patients undergoing lower limb orthopedic surgery as it may result in a decrease in the maximum sensory level.

Nonpneumatic Anti-Shock Garment versus Intermittent Sequential Compression Device for Prevention of Postspinal Hypotension in Patients Undergoing Cesarean Section: A Randomized Controlled Study.

CONTEXT: Postspinal hypotension remains a frequent complication of subarachnoid block during cesarean section causing further maternal and fetal adverse effects. AIMS: This study aims to evaluate and compare a continuous pressure nonpneumatic anti-shock garment (NASG) and an intermittent sequential compression device (SCD) with a control group for prevention of postspinal hypotension in women undergoing elective cesarean section. SETTINGS AND DESIGN: A randomized, observer blind, controlled study at single university hospital. SUBJECTS AND METHODS: Ninety singleton term parturients between 18 and 35 years of age undergoing cesarean section with spinal anesthesia were randomly assigned to be applied with NASG, SCD, or no device; n = 30 in each group. A standardized protocol for cohydration and anesthetic technique was followed. The primary outcome measure was incidence of hypotension defined as a decrease in systolic blood pressure of more than 20% from baseline or an absolute value <100 mmHg, whichever was higher. The secondary outcome measures were median dose of ephedrine required, incidence of maternal nausea and vomiting, and neonatal Apgar scores. STATISTICAL ANALYSIS USED: Results were expressed as mean (±standard deviation), median (range), or number (%) as appropriate. Nominal data were compared using Chi-square/Fischer's exact test. Continuous data were compared using ANOVA one-way test. Nonparametric data were compared using Kruskal-Wallis test. RESULTS: In Groups NASG, SCD, and C, incidence of hypotension was 60%, 83%, and 90%, respectively (P = 0.021), with significant reduction in incidence of hypotension in Group NASG versus Group C (P < 0.001, odds ratio 0.17, 95% confidence interval 0.04-0.68). Median (interquartile range) dose of ephedrine required was significantly less in Group NASG compared with Groups SCD and C, respectively (P = 0.002, P < 0.001). CONCLUSIONS: NASG proved to be a more effective device for prevention of postspinal hypotension when compared with application of SCD or no device.

Efficacy of local wound infiltration analgesia with ropivacaine and dexmedetomidine in tubercular spine surgery - A pilot randomised double-blind controlled trial.

BACKGROUND AND AIMS: Regional analgesic techniques are difficult to use in tubercular spine patients due to distorted spinal anatomy and presence of infection. This study was conducted with the aim to evaluate analgesic efficacy of local wound infiltration before wound closure in tubercular spine patients. METHODS: This pilot randomised double-blind controlled study was conducted in 32 American Society of Anesthesiologists I-III patients, age ≥15 years, undergoing elective surgery for spinal tuberculosis. All the patients received general anaesthesia using standard technique and intravenous morphine for intraoperative analgesia. They received wound infiltration with either normal saline (group C) or local infiltration analgesia with 0.375% ropivacaine 3 mg/kg, adrenaline 5 µg/mL and dexmedetomidine 1 µg/kg in a total volume of 0.8 mL/kg (group LIA) before wound closure. Patient-controlled analgesia using intravenous morphine provided postoperative analgesia. The primary objective was to study 24-h morphine consumption, whereas the secondary objectives included pain scores, complications and patient satisfaction. Repeated measures analysis of variance, Chi-square test and Mann-Whitney U test were used for statistical analysis. RESULTS: Morphine requirement was lower in group LIA (6.7 ± 2.7 mg) than in group C (27.7 ± 7.9 mg);P < 0.001. Group LIA also had lower pain scores (P < 0.001), longer time to rescue analgesic (P < 0.001), better patient satisfaction to pain relief (P = 0.001) and lower incidence of postoperative nausea and vomiting than group C. CONCLUSION: Wound infiltration with ropivacaine, adrenaline and dexmedetomidine before wound closure provided good postoperative analgesia with lower morphine requirement.

Risk of early postoperative acute kidney injury with stroke volume variation-guided tetrastarch versus Ringer's lactate.

BACKGROUND: Whether intraoperative use of hydroxyethyl starch (HES) solutions is associated with postoperative acute kidney injury (AKI) continues to be researched. Urinary neutrophil gelatinase-associated lipocalin (NGAL) is validated for early detection of AKI. Previous studies are limited and use empirically predefined volumes of HES solutions with serum creatinine as marker for AKI. MATERIALS AND METHODS: Adults scheduled for orthopedic surgery under general anesthesia with >200-300 mL blood loss expected were included; 40 were randomized to receive 6% HES 130/0.4 (tetrastarch) (group HES) or Ringer's lactate (group RL) boluses when stroke volume variation (SVV) >10% in supine or lateral position, or >14% in prone position. Incidence of early postoperative AKI using urinary NGAL (>100 ng/mL) was the primary outcome, and using derangement of serum creatinine was the secondary measure. RESULTS: In 38 patients, intervention was completed, and incidence of AKI (postoperative urinary NGAL >100 ng/mL) among them was 0% in both groups. Patients with urinary NGAL >50 ng/mL were insignificantly higher for group RL versus group HES (6/19 vs. 4/19) (P = 0.461), as were those with incidence of AKI as per creatinine values (5/19 vs. 4/19) (P = 1.000). Group RL had significantly higher requirement of fluid (1211 ± 758 mL vs. 689 ± 394 mL) (P = 0.013) and lower cardiac index (P < 0.05) versus group HES. CONCLUSION: SVV-guided tetrastarch and Ringer's lactate do not result in postoperative AKI diagnosed by urinary NGAL >100 ng/mL; however, an insignificant trend for better renal functions as well as significantly more efficacious volume expansion and hemodynamic stability were seen with tetrastarch instead.

Effect of intravenous phenylephrine infusion on dose requirement of intrathecal plain levobupivacaine for cesarean section: A placebo-controlled preliminary study.

BACKGROUND: Phenylephrine infusion has been shown to decrease rostral spread of plain and hyperbaric local anesthetic (LA) when compared to ephedrine infusion. However, it does not result in higher dose requirement of hyperbaric LA for cesarean section. There is no trial evaluating the effect of phenylephrine infusion on ED50 of a plain intrathecal LA. METHODS: Pregnant patients with term uncomplicated singleton pregnancy undergoing elective cesarean section were given combined spinal-epidural anesthesia. They received intrathecal plain levobupivacaine 0.5% in a dose decided by up-and-down sequential allocation method along with 25 µg fentanyl. Intravenous infusion of phenylephrine (100 µg/ml) or normal saline was initiated immediately after intrathecal injection. Systolic arterial pressure ≤0.8 times baseline was treated using rescue boluses of phenylephrine 50 µg. RESULTS: Demographic, other patient and surgical characteristics were similar in the two groups. ED50 of intrathecal plain levobupivacaine was significantly greater in phenylephrine group (5.5 mg [95% confidence interval (CI): 5.1-5.9 mg]) compared to saline group (4.2 mg [95% CI: 3.4-5.1 mg]) (P = 0.01). Maximum sensory level, time to achieve adequate block, Apgar scores, and umbilical artery pH were similar in both groups. Total phenylephrine dose and patients having significant bradycardia were lesser in the saline group. CONCLUSIONS: Intrathecal dose requirement of plain levobupivacaine is greater using phenylephrine infusion as compared to saline infusion with rescue phenylephrine boluses. When using phenylephrine as a variable dose regimen titrated to maintain blood pressure within 20% of baseline, the ED50 of plain levobupivacaine is 5.5 mg (95% CI: 5.1-5.9 mg).

Effect of thoracic epidural block on infection-induced inflammatory response: A randomized controlled trial.

PURPOSE: Epidural block decreases inflammation and oxidative stress in experimental models of sepsis as well as after surgery. There is, however, no clinical evidence evaluating its effect on infection-induced inflammatory process. The present trial evaluated the effect of thoracic epidural block (TEB) on systemic inflammatory response in patients with small intestinal perforation peritonitis. Outcome measures included systemic levels of interleukin (IL)-6, IL-10, procalcitonin, and C-reactive protein and postoperative Sepsis-Related Organ Failure Assessment scores. MATERIAL AND METHODS: Sixty adult patients undergoing emergency abdominal laparotomy without any contraindication to TEB were randomized to receive general anesthesia alone or in combination with the TEB, which was continued for 48 hours postoperatively (n = 30 each). RESULTS: Use of TEB was associated with a statistically insignificant trend of preservation of anti-inflammatory response depicted by higher levels of IL-10 and lack of alteration in proinflammatory IL-6, along with appreciably lower procalcitonin levels, decreased incidence of raised C-reactive protein levels, and better postoperative SOFA score (P > .05). It resulted in significantly better postoperative respiratory function and faster return of bowel motility (P < .05). Although the sample size is too small for conclusive statement, none of the patients developed epidural abscess. CONCLUSION: Thoracic epidural block showed a trend toward better preservation of anti-inflammatory response and clinical recovery that, however, failed to achieve statistical significance (P > .05).

Comparison of combitube, easy tube and tracheal tube for general anesthesia.

BACKGROUND & AIMS: The Combitube(®) and EasyTube™ enable effective ventilation whether placed in the trachea or esophagus and can be used in prehospital settings, as well as in "Cannot Ventilate Cannot Intubate" situations in the operating room. Whether they can be continued to provide general anesthesia, if required, is not established. Thus the efficacy of Combitube and EasyTube was evaluated and compared with the tracheal tube for general anesthesia using controlled ventilation. MATERIALS AND METHODS: Combitube, EasyTube and tracheal tubes were used in 30 patients each to secure the airway in a randomized controlled manner. Ventilatory parameters were measured along with hemodynamic variables, and characteristics related to device placement. RESULTS: There was no significant difference in the various ventilatory parameters including minute ventilation requirement to maintain eucapnia amongst the three groups at any time point. There was no hypoxia or hypercarbia in any patient at any time. Placement of EasyTube was more difficult (P = 0.01) as compared with both Combitube and tracheal tube. EasyTube and Combitube resulted in higher incidence of minor trauma than with a tracheal tube (P = 0.00). CONCLUSION: Combitube and EasyTube may be continued for general anesthesia in patients undergoing elective nonlaparoscopic surgeries of moderate duration, if placed for airway maintenance. Given the secondary observations regarding placement characteristics of the airway devices, it, however cannot be concluded that the devices are a substitute for endotracheal tube for airway maintenance per se, unless specifically indicated.

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).

Clonidine as an adjuvant to hyperbaric bupivacaine for spinal anesthesia in elderly patients undergoing lower limb orthopedic surgeries.

BACKGROUND: In elderly patients, use of adjuvant with small doses of local anesthetics is a preferred technique for spinal anesthesia for lower limb surgeries. This study tested the hypothesis that addition of small doses of clonidine augments the spinal block levels produced by hyperbaric bupivacaine in elderly without affecting the side-effects if any of clonidine in these patients. MATERIALS AND METHODS: This was a prospective, randomized, double-blind study. Above 60 years male patients were allocated to three equal groups. Group C received 9 mg hyperbaric bupivacaine without clonidine while Group C15 and Group C30 received 15 µg and 30 µg clonidine with hyperbaric bupivacaine respectively for spinal anesthesia. Effect of clonidine on sensory block levels was the primary study outcome measure. Motor blockade and hemodynamic parameters were also studied. RESULTS: A significantly higher median block levels were achieved in Group C15 (P < 0.001) and Group C30 (P = 0.015) than Group C. Highest median sensory block level, the mean times for sensory regression to T12 level and motor block regression were statistically significant between Groups C15 and C and between Groups C30 and C. On comparison of fall in systolic blood pressure trends, there was no significant difference in the clonidine groups as compared with the control group. CONCLUSIONS: In elderly patients, clonidine when used intrathecally in doses of 15 µg or 30 µg with bupivacaine, significantly potentiated the sensory block levels and duration of analgesia without affecting the trend of systolic blood pressure as compared to bupivacaine alone. Clonidine in doses of 30 µg however facilitated the ascent of sensory level block to unexpectedly higher dermatomes for a longer time.

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.

Continuous paravertebral infusion of ropivacaine with or without fentanyl for pain relief in unilateral multiple fractured ribs.

BACKGROUND: Continuous thoracic paravertebral block (TPVB) provides effective analgesia for unilateral multiple fractured ribs (MFR). However, prolonged infusion of local anaesthetic (LA) in high doses can predispose to risk of LA toxicity, which may be reduced by using safer drugs or drug combinations. This study was conducted to assess efficacy and safety of paravertebral infusion of ropivacaine and adrenaline with or without fentanyl to provide analgesia to patients with unilateral MFR. METHODS: Thirty adults, having ≥3 unilateral MFR, with no significant trauma outside chest wall, were studied. All received bolus of 0.5% ropivacaine 0.3 ml/kg through paravertebral catheter, followed by either 0.1-0.2 ml/kg/hr infusion of ropivacaine 0.375% with adrenaline 5 µg/ml in group RA or ropivacaine 0.2% with adrenaline 5 µg/ml and fentanyl 2 µg/ml in group RAF. Rescue analgesia was provided by IV morphine. RESULTS: Statistical analysis was performed using unpaired Student t-test, Chi-square test and repeated measures ANOVA. After TPVB, VAS scores, respiratory rate and PEFR improved in both groups with no significant inter-group differences. Duration of ropivacaine infusion, morphine requirements, length of ICU and hospital stay, incidence of pulmonary complications and opioid-related side-effects were similar in both groups. Ropivacaine requirement was higher in group RA than group RAF. No patient showed signs of LA toxicity. CONCLUSION: Continuous paravertebral infusion of ropivacaine 0.375% with adrenaline 5 µg/ml at 0.1-0.2 ml/kg/hr provided effective and safe analgesia to patients with unilateral MFR. Addition of fentanyl 2 µg/ml allowed reduction of ropivacaine concentration to 0.2% without decreasing efficacy or increasing opioid-related side-effects.

Factors influencing career choice in anaesthesiology.

BACKGROUND: There is a shortage of anaesthesiologists in India. The factors that prompt medical students to opt for anaesthesiology as their career are not known; neither do we have any mechanism to know a student's stress-bearing ability before he/she opts for a stressful career like anaesthesiology. We conducted an anonymous, questionnaire-based, cross-sectional survey among 200 post-graduate anaesthesiology students to know various factors that they considered while opting for this speciality, and also evaluated their stress-bearing ability using Antonovsky's 13-point sense of coherence scale. METHODS: Two-hundred anaesthesiology students were asked to complete a questionnaire regarding the factors they considered important while opting for anaesthesiology, also enumerated in order of importance the three most important factors that led to opting this career. Students also answered the questions in Antonovsky's sense of coherence (SOC) scale. RESULTS: Economic security was considered by maximum number of students (67.7%), while intellectual stimulation/challenge offered by anaesthesiology was rated first in order of importance. Influence of doctor-patient relationship was not considered by large number of students. The weak SOC score (55) (25(th) percentile) was not greatly different than the mean SOC score (60) in the survey. CONCLUSION: Increasing the exposure of students to anaesthesiology at undergraduate level and building public awareness about the speciality will prompt more students to opt for the speciality, while career counselling with regard to specific needs of a speciality and ability of a student will help in opting the speciality that best suits the student's personality.

Combined spinal epidural and epidural volume extension: Interaction of patient position and hyperbaric bupivacaine.

BACKGROUND: Previous trials have documented failure of block augmentation with epidural volume extension, when applied after the intrathecal injection of hyperbaric bupivacaine was made in sitting position. However, there is no study comparing the effect of change in patient position during block performance, on the results of epidural volume extension. MATERIALS AND METHODS: The study was conducted in two parts in American Society of Anesthesiologists physical status I or II parturients scheduled for elective cesarean section under regional anesthesia. In the first part, 28 patients were randomized to one of the two groups, depending on whether epidural volume extension was applied following the block in sitting (group SE) or lateral position (group LE) (n=14 each). In the second part of the study another 28 patients were recruited and randomized to receive the block in sitting (group S) or lateral (group L) position (n=14 each), without epidural volume extension. All patients received combined spinal epidural block using needle-through-needle technique with intrathecal injection of 9 mg hyperbaric bupivacaine (0.5%) and 10 µg fentanyl. Epidural volume extension was performed using 5 ml normal saline in groups SE and LE. RESULTS: In the first part of the study, the maximum sensory block level was higher in group LE vs. SE (P<0.05). In the second part of the study, no significant difference was seen in the maximum sensory level between group S and group L (P>0.05). CONCLUSIONS: If epidural volume extension is being applied with intention of rapid extension of sensory block when hyperbaric bupivacaine has been injected intrathecally, the combined spinal epidural block should be performed in lateral position rather than in the sitting position.

Role of repeated epidural injections in preventing post-spinal hearing loss.

STUDY OBJECTIVE: To determine if epidural volume extension and continued postoperative epidural injections prevent hearing loss associated with a 23-gauge (G) Quincke spinal needle. DESIGN: Prospective, double blinded trial. SETTING: Operating rooms. PATIENTS: 30 adult patients scheduled for lower abdominal or perineal surgery during spinal anesthesia. INTERVENTIONS: Patients were divided into two groups of 15 each. All patients received subarachnoid injection with a 23-G Quincke needle. While patients in Group S received a single-shot spinal, Group E patients underwent epidural catheter placement one intervertebral space above. The epidural catheter was bolused with 10 mL of normal saline followed by postoperative epidural boluses of local anesthetic for analgesia as needed. MEASUREMENTS: Patients' auditory function was evaluated by pure tone audiometry (frequencies of 250-8,000 Hz) on the day before and two days after receiving the spinal anesthesia. MAIN RESULTS: Unilateral low-frequency hearing loss (500 Hz) was seen in Group S (P < 0.05). It was prevented by the repeated epidural injections as used in Group E. CONCLUSION: Following spinal anesthesia, epidural volume extension with 10 mL of normal saline followed by epidural local anesthetic boluses titrated to adequate postoperative analgesia (6-8 mL each time) prevents post-spinal hearing loss.

The microcirculation in sepsis.

SUMMARY: Sepsis is a leading cause of mortality in critically ill patients. The pathophysiology of sepsis involves a highly complex and integrated response, including the activation of various cell types, inflammatory mediators, and the haemostatic system. Recent evidence suggests an emerging role of the microcirculation in sepsis, necessitating a shift in our locus away Irom the macrohaemodynamics to ill icrohaemodynanmics in a septic patient. This review article provides a brief overview of the microcirculation, its assessment techniques, and specific therapies to resuscitate the microhaemodynamics.

Epidural volume extension and intrathecal dose requirement: plain versus hyperbaric bupivacaine.

BACKGROUND: Epidural volume extension leads to an increase in sensory spread of local anesthetic, but whether this translates into lower dose requirements during combined spinal epidural (CSE) remains undetermined. Likewise, the influence of intrathecal drug baricity on the dose-sparing effect of epidural volume extension has not been investigated. We studied the dose-sparing effect of epidural volume extension and its relation to intrathecal drug baricity by comparing the ED(50) of plain and hyperbaric bupivacaine with and without epidural volume extension. METHODS: Eighty-eight adult male patients scheduled for lower limb orthopedic surgery under CSE in the sitting position were randomized to four groups (n = 22 each); intrathecal injection was made with plain bupivacaine in groups plain bupivacaine (PB) and plain bupivacaine with epidural volume extension (PBE), and hyperbaric bupivacaine in groups hyperbaric bupivacaine (HB) and hyperbaric bupivacaine with epidural volume extension (HBE). Fentanyl, 25 microg, was added to the intrathecal drug in all groups. Among these four groups, epidural volume extension was performed with 10 mL normal saline only for groups PBE and HBE. The dose of spinal bupivacaine was varied using the up-and-down sequential allocation method. The first patient of each group received 10 mg bupivacaine. A successful spinal block was defined as attainment of sensory level of at least T10 along with complete motor blockade within 20 min of the intrathecal injection. The dose of bupivacaine was sequentially increased or decreased by 1 mg depending on whether spinal block was a failure or success in the previous patient. RESULTS: The addition of epidural volume extension to plain bupivacaine, i.e., group PBE versus group PB, resulted in a significant decrease in ED(50) (relative potency estimate: 1.2, 95% CI: 1.04-1.64) and increase in maximum sensory level (T6 vs T8, respectively, P < 0.05). These differences were not seen with hyperbaric bupivacaine (group HB vs HBE). Independent of the effect of epidural volume extension, the ED(50) of plain bupivacaine when compared with hyperbaric bupivacaine was significantly lower (relative potency estimate of group PB vs group HB: 0.78, 95% CI: 0.54-0.93; and for group PBE vs group HBE: 0.68, 95% CI: 0.37-0.87). CONCLUSIONS: Administered with or without epidural volume extension, plain bupivacaine appears to be more effective, requiring a smaller dose and producing a higher sensory block with an earlier onset in comparison to hyperbaric bupivacaine. Epidural volume extension, when applied to intrathecal hyperbaric bupivacaine, fails to decrease the dose or raise the level of block.

Autonomic dysfunction and adrenal insufficiency in thoracic spine tuberculosis.

While autonomic dysfunction has been reported in patients with spinal TB, little is known of the consequences. We matched 25 paraplegic patients with thoracic spine tuberculosis scheduled for spinal surgery (Group S) with 25 nontubercular American Society of Anesthesiologists Grade I patients scheduled for nonspinal surgeries (Group C) under identical operative conditions. All patients underwent four autonomic tests in the operating room, and a preoperative adrenocorticotropic hormone stimulation test was performed for patients in Group S. Compared to Group C, Group S had higher resting heart rate (103 +/- 20 beats/minute versus 81 +/- 10 beats/minute), lower expiratory:inspiratory ratio (1.14 +/- 0.11 versus 1.22 +/- 0.10), and higher heart rate variability (20 +/- 12 beats/minute versus 14 +/- 7 beats/minute), indicating probable parasympathetic dysfunction along with a relative sympathetic overactivity. Eight of the 17 patients who received an adrenocorticotropic hormone stimulation test had evidence of adrenal insufficiency. Incidence of hypotension in Group S and Group C was 100% and 44%, respectively. Mean systolic and diastolic blood pressure in Group S showed substantial decrease after induction and positioning of patients not associated with compensatory tachycardia. Coexisting pulmonary tuberculosis appears an important determinant of surgical approach as well as postoperative respiratory morbidity.