Conventional fluid management versus plethysmographic variability index-based goal directed fluid management in patients undergoing spine surgery in the prone position - a randomised control trial.

INTRODUCTION: The plethysmographic variability index (PVI) is a dynamic approach for assessing volume status. This study aims to compare conventional fluid management and PVI based goal-directed fluid management (GDFM) during elective spine surgery in the prone position. MATERIAL AND METHODS: Sixty-six adult patients, ASA I-II, scheduled for elective lumbar spine procedures under general anaesthesia in the prone position were included. Patients were randomly divided into either the Conventional Group with the conventional fluid management protocol or the PVI Group with the PVI-based GDFM protocol. The total amount of intraoperative crystalloid administered was set as a primary outcome. Intraoperative PVI and perfusion index (PI), mean arterial pressure (MAP), heart rate (HR), the incidence of hypotension after prone positioning in both groups and data from arterial blood gas samples (immediately after induction of anaesthesia [T1] and immediately postoperatively [T2]) were set as secondary outcomes. RESULTS: The total amount of intraoperative crystalloids, blood transfusion, urine output, and fluid balance were similar in the two groups ( P -values 0.443, 0.317 and 0.273, respectively). The perioperative MAP and HR values showed no significant differences between the two groups at all time points of measurements. The values of pH, PaO 2 , PaCO 2 , HCO 3 , lactate and haemoglobin showed no statistically significant difference between the two groups. The blood lactate value at T2 was significantly increased when compared to T1 values in the two groups. CONCLUSIONS: PVI dependent goal-directed fluid management (GDFM) therapy did not reduce the intraoperative total crystalloid administration or requirements for blood transfusion when compared to conventional fluid management using a fixed fluid rate in patients undergoing spine surgery in a prone position. Clinical trial registration: The study was registered at clinicaltrials.gov (NCT05239286).

Analgesic efficacy of two different volumes of local anaesthetics in ultrasound-guided modified approach to the thoracolumbar interfascial plane block in patients undergoing lumbar spine surgeries: a randomized controlled trial.

INTRODUCTION: There is a lack of clarity regarding the ideal local anaesthetic volume for modified thoracolumbar interfascial plane (mTLIP) block. This study was designed to investigate the analgesic efficacy of two different volumes of bupivacaine 0.25% (20 mL, and 10 mL) for ultrasound-guided mTLIP block in patients undergoing lumbar spine surgeries. MATERIAL AND METHODS: A total of 80 patients received single shot of bilateral mTLIP block at the mid- level of the operative intervention and were randomly allocated into one of the two groups to receive either 10 or 20 mL 0.25% bupivacaine on each side. Total morphine consumption in the first 24 hours postoperative was set as the primary outcome. Time to first rescue analgesia and Numeric Rating Scale (NRS) were set as secondary outcomes. RESULTS: There was no significant difference in the primary outcome: 6.20 ± 2.18 mg (10 mL Group) vs. 5 ± 0.00 mg (20 mL Group), P = 0.056. The time of first request of rescue morphine was significantly shorter in 10 mL Group (7.80 ± 3.98 hours) as compared to the 20 mL Group (13.23 ± 3.00 hours), P < 0.001. NRS at rest and movement in all time measurements was significantly higher in 10 mL Group. CONCLUSIONS: Bilateral mTLIP block using 40 mL of 0.25% bupivacaine (20 mL on each side) increased the postoperative total analgesic duration for lumbar spine surgeries, and was associated with a lower postoperative pain scores compared to 20 mL of 0.25% bupivacaine (10 mL on each side). CLINICAL TRIAL REGISTRATION ID: The study was registered at clinicaltrials.gov (ID: NCT05276908) before patient's enrolment.

Binary PSO with Classification Trees Algorithm for Enhancing Power Efficiency in 5G Networks.

The dense deployment of small cells (SCs) in the 5G heterogeneous networks (HetNets) fulfills the demand for vast connectivity and larger data rates. Unfortunately, the power efficiency (PE) of the network is reduced because of the elevated power consumption of the densely deployed SCs and the interference that arise between them. An approach to ameliorate the PE is proposed by switching off the redundant SCs using machine learning (ML) techniques while sustaining the quality of service (QoS) for each user. In this paper, a linearly increasing inertia weight-binary particle swarm optimization (IW-BPSO) algorithm for SC on/off switching is proposed to minimize the power consumption of the network. Moreover, a soft frequency reuse (SFR) algorithm is proposed using classification trees (CTs) to alleviate the interference and elevate the system throughput. The results show that the proposed algorithms outperform the other conventional algorithms, as they reduce the power consumption of the network and the interference among the SCs, ameliorating the total throughput and the PE of the system.

Perfusion index-derived parameters as predictors of hypotension after induction of general anaesthesia: a prospective cohort study.

BACKGROUND: Induction of general anaesthesia is commonly associated with hypotension. This exposes patients to perioperative organ hypoperfusion and eventually damage. This study was designed to assess the ability of preoperative perfusion index (PI), plethysmographic variability index (PVI), and dicrotic plethysmography (Dicpleth) to predict hypotension after induction of general anaesthesia. METHODS: In this cohort study, 95 ASA I and II adult patients who were scheduled for elective surgery under general anaesthesia were enrolled. The correlation between preoperative PI, PVI, Dicpleth and percentage decrease in mean arterial blood pressure after anaesthesia induction was investigated. Ability of PI, PVI, Dicpleth to detect post-induction hypotension was also analysed. RESULTS: The percent decrease in MAP after anaesthesia correlated with baseline PI (r = -0.45, P < 0.001), PVI (r = 0.45, P = 0.001) and Dicpleth (r = 0.16, P = 0.12). The PI cut-off value was ≤ 3.03 for a patient at risk for post-induction hypotension with 77.8% sensitivity, 75% specificity, positive and negative predictive values of 74.5% and 78.3%, respectively. Similarly, the ROC analysis revealed that baseline PVI (AUC = 0.73, 95% CI = 0.622-0.812) was suitable for detecting post-induction hypotension. Moreover, baseline Dicpleth (AUC = 0.63) showed significant predictive ability. CONCLUSIONS: The pre-anaesthetic PI and PVI 17, respectively, have a good ability to predict those at risk of developing post-induction hypotension in adult patients undergoing elective surgery under general anaesthesia. Future studies are needed in order to investigate the usefulness of Dicpleth in different circumstances during anaesthesia. Clinical trial registration ID: The study was registered at clinicaltrials.gov (NCT04217226).

Perfusion index as an objective measure of postoperative pain in children undergoing adenotonsillectomy: a cohort study.

Postoperative pain in children is usually undertreated because of their inability to complain. While several pain assessment scales have been developed, they have shortcomings such as subjectivity and being observer-dependent. This study aimed to assess the validity of the perfusion index as an objective measure of postoperative pain in children undergoing adenotonsillectomy. Children aged 3-7 years were enrolled. The Children's Hospital of Eastern Ontario Scale (CHEOPS) was used to assess postoperative pain. The perfusion index was measured at the same time intervals as CHEOPS. The highest CHEOPS before rescue analgesia was administered and CHEOPS when the patients became pain-free were recorded with the corresponding perfusion index. The primary outcome was the correlation between the postoperative CHEOPS and the corresponding postoperative perfusion index. The secondary outcomes were the ability of perfusion index changes to predict the presence of postoperative pain and patients' response to analgesics. The postoperative perfusion index was negatively correlated with CHEOPS at 30 and 90 min postoperatively. The change in the preoperative baseline perfusion index (ΔPI-pre) was moderately correlated with the highest CHEOPS (CHEOPS-1) (r = 0.61, p = 0.001). The change in the postoperative perfusion index (ΔPI-po) was negatively correlated with the change in the CHEOPS (ΔCHEOPS) (r = - 0.53, P = 0.0001). The ΔPI-pre was an excellent predictor of postoperative pain (AUROC 0.83 with 71% sensitivity, 83% specificity, and a cut-off value of ≥ 0.26). The perfusion index is a good objective measure for predicting the presence of postoperative pain in children undergoing adenotonsillectomy under general anesthesia. Trial registration: ClinicalTrials.gov; ID: (NCT03854604) registered on February 2019.

Analgesic and hemodynamic effects of intravenous infusion of magnesium sulphate versus dexmedetomidine in patients undergoing bilateral inguinal hernial surgeries under spinal anesthesia: a randomized controlled study.

BACKGROUND: Spinal anesthesia is commonly employed during inguinal hernial surgeries. Its short duration may, however, be considered a limitation, especially for bilateral hernial repair. The aim of this research is to investigate the analgesic and hemodynamic effects of intravenous infusion of both MgSO4 and dexmedetomidine on patients undergoing bilateral inguinal hernia surgeries under spinal anesthesia. METHODS: This study was a prospective, randomized, double-blinded controlled trail. It included 60 male patients who had been scheduled for bilateral elective inguinal hernia surgery under spinal anesthesia at Kasr Al-Aini hospital. Patients were randomly allocated to one of three groups (n = 20 each) to receive 50 mL of 0.9% saline intravenous infusion of either dexmedetomidine 0.5 µg.kg-1. h-1 (Group D) or magnesium sulphate 15 mg.kg-1. h-1 (Group M) or normal saline (Group S). The primary outcome of this study was set as the total duration of analgesia. Secondary outcomes were set as the onset and duration of sensory and motor blockade, perioperative hemodynamics, and the total 24-hour postoperative morphine consumption. RESULTS: Durations of sensory and motor blockades as well as durations of analgesia were all significantly longer among patients in Group D (mean 2.2, 3.5, 5.8 hours respectively) and Group M (mean 2.2, 3.3, 5.2 hours respectively), in comparison to Group S (mean 1.5, 2.7, 3.9 hours respectively). No significant differences were found in systolic or diastolic arterial blood pressure, heart rate oxygen saturation, cardiac output, or stroke volume among the study groups. Seven patients in Group D and four patients in Groups M and S developed hypotension. CONCLUSION: Intravenous infusion of either dexmedetomidine or MgSO4 with spinal anesthesia effectively improves the quality of spinal anesthesia and prolongs the duration of postoperative analgesia and decreases the 24-hour postoperative morphine consumption. Results also demonstrated that the use of dexmedetomidine resulted in a slightly longer duration of analgesia, whilst the use of MgSO4 resulted in slightly better hemodynamic stability.

Evaluation of super-obesity and super-super-obesity as risk factors for difficult intubation in patients undergoing bariatric surgery.

BACKGROUND: Super-obesity is a serious disorder which requires bariatric surgery. The association of super-obesity and difficult intubation was not adequately established. OBJECTIVES: To determine if super-obesity and super-super-obesity are associated with difficult intubation or not. SETTING: University Hospital. METHODS: A cohort of obese patients scheduled for bariatric surgery was prospectively recruited. Super-obesity and super-super-obesity were defined as body mass index ≥50 kg/m2 and 60 kg/m2, respectively. Intubation difficulty was assessed by 2 methods: (1) intubation difficulty scale; (2) number of intubation attempts. Risk factors for difficult intubation were recorded. Univariate and multivariate analysis for risk factors for difficult intubation and difficult mask ventilation were performed. RESULTS: A total of 658 patients were enrolled in the study including 205 (31%) super-obese and 52 (8%) super-super-obese patients. Ninety-nine (15%) patients required more than 1 intubation attempt, while 215 (33%) patients had intubation difficulty scale ≥5. Ninety-four (14.4%) patients had mask ventilation of moderate difficulty, while only 2 (.3%) patients needed 2-person ventilation. The independent risk factors for difficult intubation using the two stated definitions were STOP-Bang and Mallampati score values. The independent risk factors for mask ventilation of moderate difficulty were STOP-Bang score, Mallampati score, and limited neck extension. CONCLUSION: Within obese patients, neither super-obesity nor super-super-obesity was associated with difficult intubation or difficult mask ventilation. High STOP-Bang and Mallampati score are the independent factors for difficult intubation.

Ketamine-based Versus Fentanyl-based Regimen for Rapid-sequence Endotracheal Intubation in Patients with Septic Shock: A Randomised Controlled Trial.

Objective: The aim of this work is to compared ketamine-based versus fentanyl-based regimens for endotracheal intubation in patients with septic shock undergoing emergency surgery. Design: This was a randomised double-blinded controlled trial. Participants: Patients with septic shock on norepinephrine infusion scheduled for emergency surgery. Setting and Interventions: At induction of anaesthesia, patients were allocated into ketamine group (n=23) in which the participants received ketamine 1 mg/kg, and fentanyl group (n=19) in which the participants received fentanyl 2.5 mcg/ kg. Both groups received midazolam (0.05 mg/kg) and succinyl choline (1 mg/kg). Measurement: The primary outcome was mean arterial blood pressure. The secondary outcomes included: heart rate, cardiac output, and incidence of postintubation hypotension defined as mean arterial pressure ≤80% of baseline value. Results: Forty-two patients were available for final analysis. The mean blood pressure was higher in the ketamine group than in the fentanyl group at 1, 2 and 5 minutes after the induction of anaesthesia. Furthermore, the incidence of postinduction hypotension was lower in the ketamine group than in the fentanyl group (11 [47.8%] versus 16 [84.2%], P-value= 0.014). Other hypodynamic parameters, namely the heart rate and cardiac output, were comparable between both groups; and were generally maintained in relation to the baseline reading in each group. Conclusion: The ketamine-based regimen provided better hemodynamic profile compared to fentanyl-based regimen for rapid-sequence intubation in patients with septic shock undergoing emergency surgery.

Hemodynamic effects of norepinephrine versus phenylephrine infusion for prophylaxis against spinal anesthesia-induced hypotension in the elderly population undergoing hip fracture surgery: a randomized controlled trial.

BACKGROUND: Elderly population are at increased risk of spinal anesthesia-induced hypotension increasing their risk for postoperative morbidity and mortality. This study aimed to compare the hemodynamic effects of prophylactic infusion of norepinephrine (NE) versus phenylephrine (PE) in elderly patients undergoing hip fracture surgery under spinal anesthesia. METHODS: Elderly patients scheduled for hip fracture surgery were randomized to receive either NE infusion (8 µg/min) (NE group, n = 31) or PE infusion (100 µg/min) (PE group, n = 31) after spinal anesthesia. Outcomes included mean heart rate, mean blood pressure, cardiac output, incidence of spinal anesthesia-induced hypotension, incidence of bradycardia, and incidence of hypertension. RESULTS: Sixty-two patients with a mean age of 71 ± 6 years were included in the final analysis (31 patients in each group). The NE group showed a higher mean heart rate and cardiac output than the PE group. The NE group had a lower incidence of reactive bradycardia (10% vs. 36%, P = 0.031) and hypertension (3% vs. 36%, P = 0.003) than the PE group. No study participant developed hypotension, and the mean blood pressure was comparable between the two groups. CONCLUSIONS: Both NE and PE infusions effectively prevented spinal anesthesia-induced hypotension in elderly patients undergoing hip fracture surgery. However, NE provided more hemodynamic stability than PE; maintaining the heart rate, higher cardiac output, less reactive bradycardia, and hypertension.

Intraoperative MgSO4 infusion protects oxygenation and lung mechanics in COPD patients during general anesthesia. A randomized clinical trial.

BACKGROUND: The purpose of this study was to examine the effects of an intraoperative MgSO4 infusion on arterial oxygenation and lung mechanics in patients with moderate COPD undergoing cancer larynx surgery under general anesthesia (GA). Our primary outcome was arterial oxygenation determined by the PaO2 and PaO2 /FiO2 . The secondary outcomes were lung mechanics (peak airway pressure, airway plateau pressure, dead space, lung compliance, airway resistance) and postoperative complications. METHODS: In this randomized controlled double-blinded trial, 40 patients with an ASA classifications II and/or III who were diagnosed with moderate COPD and who were scheduled for cancer larynx surgery under GA were randomly allocated into two equal groups, the target (Mg group) and control group (C group). In the Mg group, 30 mg/kg of 10% MgSO4 solution was administered intravenously for over 20 minutes as the loading dose, followed by the continuous infusion of 10 mg/kg/hr In the C group, the same loading and maintenance infusion rates were administered using 0.9% saline. RESULTS: Unlike the C group (baseline "T0" to post-infusion "T1" interval 294 ± 97 vs 238 ± 71 mm Hg, respectively, P = .04 ± SD), the Mg group exhibited preserved intraoperative PaO2 (T0 to T1 interval 271 ± 89 vs 257 ± 53 mm Hg, respectively, P = .54 ± SD) and PaO2 /FiO2 (C group T0 to T1 interval 404 ± 81 vs 349 ± 84, P = .04 and Mg group 394 ± 91 vs 379 ± 95, P = .61, respectively), and these effects were modest. Further, compared to the C group, the Mg group exhibited lower airway resistance, dead space, airway plateau pressure, and peak airway pressure, and higher dynamic compliance. The postoperative PaO2 and PaO2 /FiO2 were higher in the Mg group compared to the C group. CONCLUSIONS: Intraoperative infusion of MgSO4 in patients with moderate COPD undergoing laryngectomy surgery under GA produces mild perioperative protective effects on both arterial oxygenation and lung mechanics. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03461328; registration date: 8 March 2018.

Comparison between the ultrasound-guided erector spinae block and the subcostal approach to the transversus abdominis plane block in obese patients undergoing sleeve gastrectomy: a randomized controlled trial.

BACKGROUND: Pain control in the morbidly obese has presented as an anesthetic challenge. The aim of this study is to assess the analgesic efficacy of ultrasound guided bilateral erector spinae block compared to bilateral subcostal transversus abdominis plane block. METHODS: A prospective randomized, double-blinded controlled study was conducted at Kasr Alainy Hospital on 66 patients scheduled for laparoscopic sleeve gastrectomy. Patients were randomly allocated into three groups and received general anesthesia: bilateral erector spinae block at the level of T9 or bilateral subcostal transversus abdominis block or opioid analgesia (control group). The primary outcome was pain assessment by Visual Analogue Scale. RESULTS: Visual Analogue Scale was lower in the erector spinae and transversus abdominis groups compared with the control group throughout the first 12 postoperative hours (P≤0.001). Visual Analogue Scale was lower in the erector spinae group in relation to control group at 18 postoperative hours (P=0.034). Visual Analogue Scale in the erector spinae group was significantly lower compared to transversus abdominis at the 12 postoperative hours. Twenty-four-hour postoperative pethidine consumption was higher in the control group (median 150, IQR 100-200) compared to both erector spinae (median 0, IQR 0-50) and transversus abdominis (median 50, IQR 0-100) groups (P<0.001). Erector spinae group showed less pethidine consumption than transversus abdominis group. CONCLUSIONS: Ultrasound-guided single-shot T9 erector spinae plane block lowers postoperative pain scores, and reduces intraoperative and postoperative opioid consumption compared with both the subcostal approach transversus abdominis plane block and the control group in obese patients that had undergone sleeve gastrectomy.

Accuracy and trending of non-invasive oscillometric blood pressure monitoring at the wrist in obese patients.

BACKGROUND: In obese patients, non-invasive blood pressure monitoring in the arm is difficult due to the arm size and morphology. We compared the non-invasive oscillometric wrist blood pressure measurement with the arm and forearm in obese patients monitored with invasive radial blood pressure (reference standard). METHODS: This prospective observational study included adult obese patients scheduled for bariatric surgery. Non-invasive blood pressure was measured at the arm, upper forearm and wrist of one upper extremity, while invasive blood pressure was simultaneously measured through a radial arterial catheter in the contralateral upper extremity. The accuracy of non-invasive blood pressure reading at each site was evaluated for absolute and trending values using the Bland-Altman analysis and Spearman's correlation coefficient. RESULTS: In 40 patients, 262, 259, and 263 pairs of non-invasive blood pressure readings were obtained from the arm, forearm, and wrist sites, respectively. As primary outcome, the correlation coefficient for systolic blood pressure was higher for the wrist (0.92, 95% confidence interval (CI) [0.9-0.94]) than for the arm (0.74, 95% CI [0.68-0.79]) and the forearm (0.71, 95% CI [0.64-0.76]) (P<0.05). The non-invasive systolic wrist blood pressure showed the least mean bias and the narrowest limits of agreement (-0.3±7.6mmHg) when compared with forearm (4.3±16) and arm measurements (14.2±13.6) (P<0.05). For trending values, the correlation coefficient was the highest at the wrist. CONCLUSION: In obese patients undergoing bariatric surgery, non-invasive blood pressure measured at the wrist showed the highest accuracy in comparison with the arm and forearm.

The ability of perfusion index to detect segmental ulnar nerve sparing after supraclavicular nerve block.

Supraclavicular nerve block (SCB) is a commonly used regional block for upper extremity surgery. The most common form of failure of SCB is ulnar segmental sparing. We aimed to evaluate the accuracy of perfusion index (PI) in early detection of segmental sparing of the ulnar component of SCB. A prospective observational study included adult patients scheduled for surgery under ultrasound-guided SCB. PI was simultaneously measured at the index finger and little finger. PI was recorded every minute for the first 10 min after SCB. PI ratio was calculated at every measurement point as PI/baseline PI. The area under the receiver operating characteristic (AUROC) curve was calculated for the ability of PI ratio to detect segmental ulnar sparing with comparison of little finger readings to the index finger readings. Forty-nine patients were available for the final analysis. Nine patients (18%) had segmental ulnar sparing. PI ratio at the little finger showed excellent predictive ability for ulnar sparing starting from the fifth minute (AUROC 0.92 [0.8-0.98], cutoff value ≤ 1.71) and reached the highest value at the seventh minute (AUROC 0.96 [0.86-1], cutoff value ≤ 1.35), whereas PI ratio at the index finger showed poor predictive ability. When using the PI for evaluation of successful SCB, segmental ulnar sparing could be accurately detected when the PI was measured at the little finger and not at the index finger. An increase of 71% in PI at the little finger 5 min after SCB could accurately rule out ulnar sparing.Clinical trial identifier NCT03880201. Clinical trial registration https://clinicaltrials.gov/ct2/show/NCT03880201?term=NCT03880201&draw=2&rank=1 .

Comparative study between intrathecal dexmedetomidine and intrathecal magnesium sulfate for the prevention of post-spinal anaesthesia shivering in uroscopic surgery; (RCT).

BACKGROUND: Hypothermia and shivering are common complications after spinal anaesthesia, especially after uroscopic procedures in which large amounts of cold intraluminal irrigation fluids are used. Magnesium sulfate and dexmedetomidine are the most effective adjuvants with the least side effects. The aim of this study was to compare the effects of intrathecal dexmedetomidine versus intrathecal magnesium sulfate on the prevention of post-spinal anaesthesia shivering. METHODS: This prospective randomized, double-blinded controlled study included 105 patients who were scheduled for uroscopic surgery at the Kasr El-Aini Hospital. The patients were randomly allocated into three groups. Group C (n = 35) received 2.5 ml of hyperbaric bupivacaine 0.5% (12.5 mg) + 0.5 ml of normal saline, Group M (n = 35) received 2.5 ml of hyperbaric bupivacaine 0.5% (12.5 mg) + 25 mg of magnesium sulfate in 0.5 ml saline, and Group D (n = 35) received 2.5 ml of hyperbaric bupivacaine 0.5% (12.5 mg) + 5 µg of dexmedetomidine in 0.5 ml saline. The primary outcomes were the incidence and intensity of shivering. The secondary outcomes were the incidence of hypothermia, sedation, the use of meperidine to control shivering and complications. RESULTS: Group C had significantly higher proportions of patients who developed shivering (21), developed grade IV shivering (20) and required meperidine (21) to treat shivering than group M (8,5,5) and group D (5,3,6), which were comparable to each other. The time between block administration and meperidine administration was similar among the three groups. Hypothermia did not occur in any of the patients. The three groups were comparable regarding the occurrence of nausea, vomiting, bradycardia and hypotension. All the patients in group C, 32 patients in group M and 33 patients in group D had a sedation score of 2. Three patients in group M and 2 patients in group D had a sedation score of 3. CONCLUSIONS: Intrathecal injections of both dexmedetomidine and magnesium sulfate were effective in reducing the incidence of post-spinal anaesthesia shivering. Therefore, we encourage the use of magnesium sulfate, as it is more physiologically available, more readily available in most operating theatres and much less expensive than dexmedetomidine. TRIAL REGISTRATION: Clinical trial registration ID: Pan African Clinical Trial Registry (PACTR) Trial Number PACTR201801003001727 ; January 2018, "retrospectively registered".

Evaluation of the effects of dexmedetomidine infusion on oxygenation and lung mechanics in morbidly obese patients with restrictive lung disease.

BACKGROUND: Dexmedetomidine infusion improves oxygenation and lung mechanics in patients with chronic obstructive lung disease; however, its effect in patients with restrictive lung disease has not been thoroughly investigated yet. The aim of this work was to evaluate the effects of dexmedetomidine infusion on oxygenation and lung mechanics in morbidly obese patients with restrictive lung disease. METHODS: Forty-two morbidly obese patients scheduled for bariatric surgery were included in the study. Patients were randomized to receive either dexmedetomidine infusion at a bolus dose of 1mcg/Kg followed by infusion at 1 mcg/Kg/hour for 90 min (Dexmedetomidine group), or normal saline infusion (Control group). Both groups were compared with regard to: oxygenation {P/F ratio: PaO2/fraction of inspired oxygen (FiO2)}, lung compliance, dead space, plateau pressure, blood pressure, and heart rate. RESULTS: Dexmedetomidine group showed significant improvement of the PaO2/FiO2 ratio, and higher lung compliance compared to control group by the end of drug infusion. Dexmedetomidine group demonstrated decreased dead space, plateau pressure, blood pressure, and heart rate compared to control group by the end of drug infusion. CONCLUSION: A 90-min dexmedetomidine infusion resulted in moderate improvement in oxygenation and lung mechanics in morbidly obese patients with restrictive lung disease. TRIAL REGISTRATION: clinicaltrials.gov : NCT02843698 on 20 July 2016.

Nalbuphine as an adjuvant to 0.25% levobupivacaine in ultrasound-guided supraclavicular block provided prolonged sensory block and similar motor block durations (RCT).

PURPOSE: Prolonged postoperative analgesia with early motor recovery for early rehabilitation is a challenge in regional block. The purpose of this study is to evaluate the effect of adding 20 mg nalbuphine to 25 ml of 0.25% levobupivacaine in supraclavicular brachial plexus block. METHODS: One hundred thirty-five (135) patients scheduled for hand and forearm surgeries with supraclavicular block were randomly allocated into three equal groups. Group L received 25 ml of 0.5% levobupivacaine + 1 ml normal saline; group H received 25 ml of 0.25% levobupivacaine + 1 ml normal saline; and group N received 25 ml of 0.25% levobupivacaine + 1 ml (20 mg) nalbuphine. Onset time and duration of sensory and motor block, and time to first analgesic dose were recorded. RESULTS: Sensory block onset was comparable between the three groups. Motor block onset in group L and group N was comparable (13.16 ± 3.07 and 13.84 ± 3.05 min, respectively) and was shorter than that in group H (15.71 ± 2 0.91 min). Sensory block duration in group L and group N was comparable (522.22 ± 69.57 and 533.78 ± 66.03 min, respectively) and was longer than that in group H (342.67 ± 92.80 min). Motor block duration in group N and group H was comparable (272.00 ± 59.45 and 249.78 ± 66.01 min, respectively) and was shorter than that in group L (334.67 ± 57.90 min). Time to first analgesic dose was significantly longer in group N (649.78 ± 114.76 min) than that of group L and group H (575.56 ± 96.85 and 375.56 ± 84.49 min, respectively) and longer in group L when compared to group H. CONCLUSIONS: Adding 20 mg nalbuphine to 25 ml of 0.25% levobupivacaine in supraclavicular block provided prolonged duration of sensory block with similar duration of motor block.

Accuracy and trending of non-invasive hemoglobin measurement during different volume and perfusion statuses.

The evolution of non-invasive hemoglobin measuring technology would save time and improve transfusion practice. The validity of pulse co-oximetry hemoglobin (SpHb) measurement in the perioperative setting was previously evaluated; however, the accuracy of SpHb in different volume statuses as well as in different perfusion states was not well investigated. The aim of this work is to evaluate the accuracy and trending of SpHb in comparison to laboratory hemoglobin (Lab-Hb) during acute bleeding and after resuscitation. Seventy patients scheduled for major orthopedic procedures with anticipated major blood loss were included. Radical-7 device was used for continuous assessment of SpHb, volume status [via pleth variability index (PVI)] and perfusion status [via perfusion index (PI)]. Lab-Hb and SpHb were measured at three time-points, a baseline reading, after major bleeding, and after resuscitation. Samples were divided into fluid-responsive and fluid non-responsive samples, and were also divided into high-PI and low-PI samples. Accuracy of SpHb was determined using Bland-Altman analysis. Trending of SpHb was evaluated using polar plot analysis. We obtained 210 time-matched readings. Fluid non-responsive samples were 106 (50.5%) whereas fluid responsive samples were 104 (49.5%). Excellent correlation was reported between Lab-Hb and SpHb (r = 0.938). Excellent accuracy with moderate levels of agreement was also reported between both measures among all samples, fluid non-responsive samples, fluid-responsive samples, high-PI samples, and low-PI samples [Mean bias (limits of agreement): 0.01 (- 1.33 and 1.34) g/dL, - 0.08 (- 1.27 and 1.11) g/dL, 0.09 (- 1.36 and 1.54) g/dL, 0.01 (- 1.34 to 1.31) g/dL, and 0.04 (- 1.31 to 1.39) g/dL respectively]. Polar plot analysis showed good trending ability for SpHb as a follow up monitor. In conclusion, SpHb showed excellent correlation with Lab-Hb in fluid responders, fluid non-responders, low-PI, and high PI states. Despite a favorable mean bias of 0.01 g/dL for SpHb, the relatively wide levels of agreement (- 1.3 to 1.3 g/dL) might limit its accuracy. SpHb showed good performance as a trend monitor.

Hemodynamic effects of lateral tilt before and after spinal anesthesia during cesarean delivery: an observational study.

BACKGROUND: Post-spinal hypotension is a common maternal complication during cesarean delivery. Aortocaval compression by the gravid uterus has been assumed as a precipitating factor for post-spinal hypotension. The role of left lateral tilting position in improving maternal cardiac output after subarachnoid block (SAB) is unclear. The aim of this work is to investigate the effect of left lateral tilting on maternal hemodynamics after SAB. METHODS: A prospective observational study was conducted including 105 full term pregnant women scheduled for cesarean delivery. Mean arterial pressure, heart rate, cardiac output (measured by electrical cardiometry), stroke volume, and systemic vascular resistance were recorded in three positions (supine, 150, and 300 left lateral positions) before SAB, after SAB, and after delivery of the fetus. RESULTS: Before SAB, no significant hemodynamic changes were reported with left lateral tilting. A significant decrease was reported in mean arterial pressure, cardiac output, stroke volume, and systemic vascular resistance after SAB (in supine position). When performing left lateral tilting, there was an increase in cardiac output, heart rate, and mean arterial pressure. No difference was reported between the two tilt angles (150 and 300). CONCLUSIONS: Changing position of full term pregnant woman after SAB from supine to left lateral tilted position results increased cardiac output and mean arterial pressure. There is no difference between the two tilt angles (150 and 300). TRIAL REGISTRATION: clinicaltrials.gov ( NCT02828176 ) retrospectively registered.