The accuracy of the ultrasound measured transverse cricoid diameter and the epiphyseal transverse diameter of the distal radius in predicting the pediatric endotracheal tube size.

BACKGROUND: In everyday pediatric anesthesia practice, clinicians frequently exchange an already inserted endotracheal tube because of a leak or resistance causing significant morbidity. We investigated the accuracy of two ultrasound measurements; the transverse cricoid diameter and epiphyseal diameter of the distal radius in the prediction of endotracheal tube size that best fits in children compared to age-based formulas. PATIENTS: One hundred children (1-6 years) who underwent elective surgery with endotracheal tube whether cuffed (n = 50) or uncuffed (n = 50) were enrolled. The primary endpoint was the agreement between the reference tube size for which its outer diameter was selected based on transverse cricoid diameter and the final best-fit-ETT. The Correlation and Bland Altman agreement tests were conducted between best-fit-ETT outer diameter and ultrasound-measured outer diameter, and between best-fit-ETT inner diameter and inner diameter calculated by age-based formulas. RESULTS: The agreement rate between transverse cricoid diameter-based endotracheal tube size and best-fit-ETT size was 88% in cuffed group compared to 90% in uncuffed group. A significant positive correlation was reported between the outer diameter of best-fit-ETT and the outer diameter measured by the two ultrasound methods. A lower degree of positive correlation was reported between the inner diameter of best-fit-ETT, and the inner diameter calculated by age-based formulas. Bland Altman's analysis showed agreement between best-fit-ETT outer diameter and epiphyseal diameter of the distal radius in both groups and with transverse cricoid diameter in the cuffed group, with no agreement with age-based formulas in either group. CONCLUSIONS: Both transverse cricoid diameter and epiphyseal diameter of the distal radius are reliable predictors of the size of best-fit-ETT pediatric endotracheal tube compared to age-based formulas. To save time and effort, we recommend the US measurement of the epiphyseal diameter of distal radius in the preoperative visit and documenting the predicted tube size with the preoperative assessments.

End-tidal carbon dioxide measurements as a surrogate to arterial carbon dioxide during pediatric laparoscopic surgeries: a prospective observational cohort study.

BACKGROUND: Maintaining normocapnia during mechanical ventilation in anesthetized children during laparoscopic surgeries is highly recommended. There is a debate regarding the use of capnography (ETCO2) as a trend monitor for evaluation of arterial carbon dioxide levels (PaCO2). We analyzed the relationship between ETCO2 and PaCO2 with time in elective pediatric laparoscopic surgeries. METHODS: This study was a prospective observational cohort analysis of 116 paired comparisons between PaCO2 and ETCO2 computed from 29 children (ASA I, 12-72 months). Arterial blood samples were withdrawn before, at 15 minutes and 30 minutes during pneumoperitoneum and 1 minute after deflation. ETCO2 value was recorded simultaneously, while arterial blood was withdrawn. PaCO2-ETCO2 relationship was evaluated by Pearson's correlation coefficients and Bland Altman Method of agreement. RESULTS: Out of the 116 comparisons analyzed, a PaCO2-ETCO2 difference beyond 0 to ≤ 5 mmHg was recorded in 71 comparisons (61.2%) with negative difference in 34 comparisons (29.3%). A positive significant correlation between PaCO2 and ETCO2 was recorded before (r = 0.617, p = 0.000) and at 15 minutes (r = 0.582, p = 0.001), with no significant correlation at 30 minutes (r = 0.142, p = 0.461), either after deflation (r = 0.108, p = 0.577). Bland-Altman plots showed agreement between ETCO2 and PaCO2 before inflation with mean PaCO2-ETCO2 difference 0.14 ± 5.6 mmHg (limits of 95% agreement -10.84-11.2, simple linear regression testing p-value 0.971), with no agreement at 15 minutes (0.51 ± 7.15, -13.5-14.5, p = 0.000), 30 minutes. (2.62 ± 7.83, -12.73-17.97, p = 0.000), or after deflation (1.81 ± 6.56, -10.93-14.55, p = 0.015). CONCLUSION: Usage of capnography as a trend monitor in pediatric laparoscopic surgeries may not be a reliable surrogate for PaCO2 levels. TRIAL REGISTRATION: Clinical Trials. gov (Identifier: NCT03361657).

Sphenopalatine Ganglion versus Greater Occipital Nerve Blocks in Treating Post-Dural Puncture Headache after Spinal Anesthesia for Cesarean Section: A Randomized Clinical Trial.

BACKGROUND: Despite being invasive, with serious complications, epidural blood patch (EBP) is still considered the gold standard therapy for Post Dural Puncture Headache (PDPH). The use of Peripheral nerve blocks for PDPH are studied here. OBJECTIVES: To investigate the efficacy of sphenopalatine ganglion block (SPGB) and greater occipital nerve block (GONB) to relieve PDPH and its associated symptoms. STUDY DESIGN: Randomized comparative single-blind trial. SETTING: A University hospital. METHODS: Patients who received spinal anesthesia for elective cesarean section, and then developed PDPH during hospitalization or within 5 days after dural puncture were enrolled to receive GONB (n = 47) or SPGB (n = 46) for treatment of PDPH. GONB Group: Patients received bilateral GONB using 3 mL mixture of 2 mL lidocaine 2% plus 1 mL dexamethasone 4 mg on each side of occipital region. SPGB Group: Patients received bilateral SPGB using the same mixture in each nostril. Assessments included Numeric Rating Scale (NRS) for severity of headache at supine and sitting positions, nausea NRS, neck stiffness, need for EBP, and complications. RESULTS: The supine and sitting headache NRS scores significantly decreased at 30 minutes after blocks and throughout follow-up period in both groups (P < 0.000). Clinically significant drop of NRS to < 4 was reached earlier in GONB group. There was a significant difference between groups after 2 hours in supine and sitting headache NRS scores (P = 0.020 and 0.030, respectively); however, both treatments showed similar effectiveness from the third hour afterwards (P > 0.05). Both techniques were effective in relieving neck stiffness and nausea (P < 0.000), with no adverse effects. LIMITATIONS: A limitation to this study was the small sample size. CONCLUSIONS: GONB and SPGB are equally effective in relieving symptoms of PDPH. Both techniques are safe, simple, and less invasive than EBP.

Using the Perfusion Index to predict changes in the depth of anesthesia in children compared with the A-line Autoregression Index: an observational study.

BACKGROUND: We investigated the performance of the Perfusion Index (PI) derived from pulse oximetry waveform as a tool for assessment of anesthetic depth in comparison with A-line Autoregression Index (AAI) derived from analysis of Middle-Latency Auditory Evoked Potentials (MLAEP) waveform integrated by aepEXplus monitor in children receiving sevoflurane anesthesia for tonsillectomy. METHODS: Forty-one patients (4-12 years old) were included in this study. The PI and AAI were recorded simultaneously every minute during different stages of anesthesia delivery. The statistical tests included descriptive analysis, significance tests, correlation tests, and Receiver Operating Characteristic (ROC) curve. The AAI served as a reference. RESULTS: The PI significantly decreased during light anesthesia and recovery, and significantly increased during deeper planes of anesthesia, with an inverse mirror-image relationship with the AAI. A negative correlation of low to moderate degree was detected between PI and AAI during the study (p > 0.05), that reached a statistical significance at the 5th minute during sevoflurane mask induction (r = -0.457, p = 0.008). ROC analysis at an AAI < 25 extracted the best cut-off value for PI before intubation as 1.48 (AUC = 0.698 [0.537-0.859], 94.4% sensitivity, 44.5% specificity) and at 10-minute intraoperatively as 2.4 (AUC = 0.537 [0.354-0.721], 91.7% sensitivity, 31% specificity). During recovery, at an AAI ≥ 50, the best cutoff was 1.82 (AUC = 0.661 [0.46-0.863], 100% sensitivity and 50% specificity) 2 minutes before spontaneous eye opening. CONCLUSIONS: Compared with the AAI, the PI can track changes in depth of anesthesia in pediatric patients undergoing tonsillectomy under sevoflurane anesthesia. TRIAL REGISTRATION: Clinical Trials. Gov. Identifier: NCT03412214.

Pharmacokinetics and Pharmacodynamics of 3 Doses of Oral-Mucosal Dexmedetomidine Gel for Sedative Premedication in Women Undergoing Modified Radical Mastectomy for Breast Cancer.

BACKGROUND: Buccal dexmedetomidine (DEX) produces adequate preoperative sedation and anxiolysis when used as a premedication. Formulating the drug as a gel decreases oral losses and improves the absorption of buccal DEX. We compared pharmacokinetic and pharmacodynamic properties of 3 doses of buccal DEX gel formulated in our pharmaceutical laboratory for sedative premedication in women undergoing modified radical mastectomy for breast cancer. METHODS: Thirty-six patients enrolled in 3 groups (n = 12) to receive buccal DEX gel 30 minutes before surgery at 0.5 µg/kg (DEX 0.5 group), 0.75 µg/kg (DEX 0.75 group), or 1 µg/kg (DEX 1 group). Assessments included plasma concentrations of DEX, and pharmacokinetic variables calculated with noncompartmental methods, sedative, hemodynamic and analgesic effects, and adverse effects. RESULTS: The median time to reach peak serum concentration of DEX (Tmax) was significantly shorter in patients who received 1 µg/kg (60 minutes) compared with those who received 0.5 µg/kg (120 minutes; P = .003) and 0.75 µg/kg (120 minutes; P = .004). The median (first quartile-third quartile) peak concentration of DEX (maximum plasma concentration [Cmax]) in plasma was 0.35 ng/mL (0.31-0.49), 0.37 ng/mL (0.34-0.40), and 0.54 ng/mL (0.45-0.61) in DEX 0.5, DEX 0.75, and DEX 1 groups (P = .082). The 3 doses did not produce preoperative sedation. The 1 µg/kg buccal DEX gel produced early postoperative sedation and lower intraoperative and postoperative heart rate values. Postoperative analgesia was evident in the 3 doses in a dose-dependent manner with no adverse effects. CONCLUSIONS: Provided that it is administered 60-120 minutes before surgery, sublingual administration of DEX formulated as an oral-mucosal gel may provide a safe and practical means of sedative premedication in adults.

Conjoined twins: A report of four cases.

BACKGROUND: Conjoined twin is a rarely seen congenital anomaly associated with significant morbidity and mortality. The most common types of conjoined twins are thoracopagus. Conjoined twins are either symmetrical twins or asymmetrical or heteropagus. This report records the successful separation of 2 cases of asymmetrical twins and one symmetrical twin with fused livers and diaphragm and communicating peritoneal cavities. PATIENTS AND METHODS: This study amended and strictly followed the ethical guidelines of the Helsinki declaration, our study included 4 case reports on conjoined twins (CT), 2 male and three female patients; 3 of them were parasitic and one was conjoined. We operated upon 2 parasitics and one conjoined. The 1st case died preoperatively. RESULTS: Four living children is our result. CONCLUSION: As connections between the bowel and bone of the parasite and the respective organs in the autosite are often absent, the parasite could be excised easily without any effect on the autosite. We recommend the separation of the parasite and the autosite as early as possible. In many cases, surgery results in the death of one or both of the conjoined twins, particularly if they are joined at the head or share a vital organ. Our separated twins are yet the youngest living separated twins. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03388684.

Ketamine as an adjunct to bupivacaine in infra-orbital nerve block analgesia after cleft lip repair / Cetamina como adjuvante de bupivacaína em bloqueio do nervo infraorbitário para analgesia após correção de lábio leporino

Abstract Objectives: We conducted this study to investigate the safety and analgesic efficacy of the addition of Ketamine to Bupivacaine in bilateral extra-oral infra-orbital nerve block in children undergoing cleft lip surgeries. Methods: Sixty patients were randomly allocated into two groups (n = 30), Group B received infra-orbital nerve block with 2 mL of 0.25% Bupivacaine and Group BK received 0.5 mg.kg-1 Ketamine for each side added to 1 mL of 0.5% Bupivacaine solution diluted up to 2 mL solution to 0.25% Bupivacaine concentration. Assessment parameters included; hemodynamics, recovery time, time to first oral intake, postoperative Faces Legs Activity Cry Consolability (FLACC) scores, Four-point Agitation scores, analgesic consumption and adverse effects. Results: Patients in Group BK showed lower postoperative FLACC scores during all recorded time points (p < 0.0001). Two patients in Group BK versus 12 in Group B requested for postoperative rescue analgesia (p < 0.001). There were no differences between groups in time, minutes (min), to first request for rescue analgesia. Patients in Group BK reported lower analgesic consumption (366.67 ± 45.67 vs. 240.0 ± 0.0 mg, p < 0.04). The time to first oral intake was significantly reduced in Group BK (87.67 ± 15.41 vs. 27.33 ± 8.68 min, p < 0.001). Lower postoperative Agitation scores were recorded in Group BK patients that reached a statistical significance at 45 min (0.86 ± 0.11 vs. 0.46 ± 0.16, p < 0.04) and in the first hour (h) postoperatively (1.40 ± 0.17 vs. 0.67 ± 0.14, p < 0.003). Higher parent satisfaction scores were recorded in Group BK (p < 0.04) without significant adverse effects. Conclusions: The addition of Ketamine to Bupivacaine has accentuated the analgesic efficacy of infra-orbital nerve block in children undergoing cleft lip repair surgeries.

Resumo Objetivos: Realizamos este estudo para avaliar a segurança e eficácia da analgesia com a adição de cetamina à bupivacaína em bloqueio do nervo infraorbitário, bilateral e extraoral, em crianças submetidas à cirurgia de lábio leporino. Métodos: Foram randomicamente alocados 60 pacientes em dois grupos (n = 30): o Grupo B recebeu bloqueio do nervo infraorbitário com bupivacaína a 0,25% (2 mL) e o Grupo BC recebeu bloqueio com cetamina (0,5 mg.kg-1) em cada lado, mais a adição de 1 mL de solução de bupivacaína a 0,5% diluída até 2 mL da concentração a 0,25%. Os parâmetros de avaliação incluíram: hemodinâmica, tempo de recuperação, tempo até a primeira ingestão oral, escores da escala FLACC (que avalia a expressão facial [Face], os movimentos das pernas [Legs], a atividade [Activity], o choro [Cry] e a consolabilidade [Consolability]), escores de agitação em escala de quatro pontos, consumo de analgésicos e efeitos adversos no pós-operatório. Resultados: Os pacientes do Grupo BC apresentaram escores FLACC mais baixos em todos os momentos mensurados no pós-operatório (p < 0,0001). Dois pacientes do Grupo BC versus 12 do Grupo B solicitaram analgesia de resgate no pós-operatório (p < 0,001). Não houve diferenças entre os grupos em relação ao tempo até a primeira solicitação de analgesia de resgate. Os pacientes do Grupo BC relataram consumo menor de analgésicos (366,67 ± 45,67 vs. 240,0 ± 0,0 mg, p < 0,04). O tempo em minutos (min) até a primeira ingestão oral foi significativamente reduzido no Grupo BC (87,67 ± 15,41 vs. 27,33 ± 8,68 min, p < 0,001). Escores mais baixos de agitação no pós-operatório foram registrados para os pacientes do Grupo BC, com significância estatística no tempo de 45 min (0,86 ± 0,11 vs. 0,46 ± 0,16; p < 0,04) e na primeira hora de pós-operatório (1,40 ± 0,17 vs. 0,67 ± 0,14; p < 0,003). Índices mais altos de satisfação dos pais foram registrados no Grupo BC (p < 0,04), sem efeitos adversos significativos. Conclusões: A adição de cetamina à bupivacaína acentuou a eficácia analgésica do bloqueio do nervo infraorbitário em crianças submetidas à cirurgia de correção de lábio leporino.

[Ketamine as an adjunct to bupivacaine in infra-orbital nerve block analgesia after cleft lip repair]. / Cetamina como adjuvante de bupivacaína em bloqueio do nervo infraorbitário para analgesia após correção de lábio leporino.

OBJECTIVES: We conducted this study to investigate the safety and analgesic efficacy of the addition of Ketamine to Bupivacaine in bilateral extra-oral infra-orbital nerve block in children undergoing cleft lip surgeries. METHODS: Sixty patients were randomly allocated into two groups (n=30), Group B received infra-orbital nerve block with 2mL of 0.25% Bupivacaine and Group BK received 0.5mg.kg-1 Ketamine for each side added to 1mL of 0.5% Bupivacaine solution diluted up to 2mL solution to 0.25% Bupivacaine concentration. Assessment parameters included; hemodynamics, recovery time, time to first oral intake, postoperative Faces Legs Activity Cry Consolability (FLACC) scores, Four-point Agitation scores, analgesic consumption and adverse effects. RESULTS: Patients in Group BK showed lower postoperative FLACC scores during all recorded time points (p<0.0001). Two patients in Group BK versus 12 in Group B requested for postoperative rescue analgesia (p<0.001). There were no differences between groups in time, minutes (min), to first request for rescue analgesia. Patients in Group BK reported lower analgesic consumption (366.67±45.67 vs. 240.0±0.0mg, p<0.04). The time to first oral intake was significantly reduced in Group BK (87.67±15.41 vs. 27.33±8.68min, p<0.001). Lower postoperative Agitation scores were recorded in Group BK patients that reached a statistical significance at 45min (0.86±0.11 vs. 0.46±0.16, p<0.04) and in the first hour (h) postoperatively (1.40±0.17 vs. 0.67±0.14, p<0.003). Higher parent satisfaction scores were recorded in Group BK (p<0.04) without significant adverse effects. CONCLUSIONS: The addition of Ketamine to Bupivacaine has accentuated the analgesic efficacy of infra-orbital nerve block in children undergoing cleft lip repair surgeries.

Topical versus caudal ketamine/bupivacaine combination for postoperative analgesia in children undergoing inguinal herniotomy.

BACKGROUND: Multiple studies claim that caudal administration of ketamine causes effective postoperative analgesia. The aim of this study was to assess the clinical effectiveness of ketamine after caudal or topical administration in pediatric patients undergoing inguinal herniotomy. PATIENTS AND METHODS: This randomized, comparative, double-blind study included eighty children (aged 6 months to 6 years) received either 1 ml/kg of 0.25% bupivacaine/ketamine 0.5 mg/kg for caudal analgesia (caudal group) or 0.3 ml/kg of 0.25% bupivacaine/ketamine 0.5 mg/kg sprayed by the surgeon around the spermatic cord and upon the ilioinguinal nerve before wound closure for topical analgesia (topical group). The duration of postoperative analgesia, pain scores, rescue analgesic consumption, sedation score, hemodynamic monitoring, and side-effects were evaluated 48 h postoperative. RESULTS: Kaplan-Meier survival analysis of analgesia free time demonstrated a significant advantage of topical ketamine (TK) group over caudal ketamine (CK) group. The duration of postoperative analgesia was longer in TK group than in CK group (28.74 ± 2.88 vs. 21.43 ± 5.01 h, P = 0.000). Fewer children asked for oral analgesics in the topical group (24 of 36, 66.7%) than in the caudal one (28 of 32, 87.5%; P < 0.01). Postoperative pain scores at the 6th till 48th h were lower in topical group with comparable analgesic consumption between two groups. In the caudal group, four subjects suffered from retention of urine: Two presented with a residual motor block and two had photophobia. CONCLUSION: Wound instillation of bupivacaine/ketamine is a simple, noninvasive, and effective technique that could be a safe alternative to CK for postoperative analgesia in children undergoing inguinal hernia repair.

Effect of Topical Morphine on Acute and Chronic Postmastectomy Pain: What Is the Optimum Dose?

BACKGROUND AND OBJECTIVES: Poorly controlled postoperative pain is strongly associated with the development of chronic pain. We aimed to investigate the effect of topical morphine (in 1 of 3 doses: 5, 10, or 15 mg) on acute and chronic neuropathic pain after modified radical mastectomy for cancer breast. METHODS: In this registered clinical trial (ClinicalTrials.gov identifier: NCT02462577), 90 patients were allocated to receive 10 mL plain bupivacaine 0.5% plus either 5, 10, or 15 mg morphine (designated by the group names Morphine5, Morphine10, and Morphine15, respectively). The combination was diluted by saline 0.9% to 20 mL and irrigated in the wound before skin closure. Groups were compared for the following: time to first postoperative analgesia; intravenous patient-controlled analgesia (PCA) morphine consumption; pain scores; hemodynamics; sedation; adverse events in first postoperative 48 hours; and Leeds Assessment of Neuropathic Symptoms and Signs scores in first and third postoperative months. RESULTS: No patient in the Morphine15 group requested postoperative PCA morphine versus 19 and 8 in the Morphine5 and Morphine10 groups, respectively (P < 0.002). Time to first analgesic request and total consumption of PCA morphine analgesia were 7.31 ± 3.12 hours versus 14.00 ± 3.54 hours (P < 0.000) and 1.42 ± 0.50 mg versus 1.00 ± 0.00 mg (P = 0.371) in the Morphine5 and Morphine10 groups, respectively. Lowest scores on visual analog pain scale at rest (P < 0.001) and visual analog pain scale during movement (P < 0.01) were recorded in the Morphine15 group, followed by Morphine10 then Morphine5 group. Lowest Leeds Assessment of Neuropathic Symptoms and Signs scores were recorded in the Morphine15 group in the first month (1.10 ± 0.37 vs 5.76 ± 3.26 and 4.73 ± 2.87, P < 0.0001) and third postoperative month (4.40 ± 1.77 vs 6.33 ± 3.21 and 5.43 ± 2.67, P < 0.006) compared with Morphine5 and Morphine10 groups, respectively. No patient in the Morphine15 group developed chronic pain versus 4 and 2 in Morphine5 and Morphine10 groups, respectively. CONCLUSIONS: Topical morphine controlled acute postmastectomy pain in a dose-dependent manner and reduced the incidence and severity of chronic postmastectomy pain syndrome.

Safety and Efficacy of Dexmedetomidine in Treating Post Spinal Anesthesia Shivering: A Randomized Clinically Controlled Dose-Finding Trial.

BACKGROUND: The optimum dose of dexmedetomidine for shivering control with the least hemodynamic derangements is still under research. OBJECTIVE: To compare the efficacy, hemodynamic and side effects of dexmedetomidine in 3 different doses with those of meperidine for the treatment of shivering in patients undergoing spinal anesthesia for minor elective lower abdominal surgery. STUDY DESIGN: Prospective double-blind randomized clinically controlled study. SETTING: University hospital. METHODS: One hundred twenty patients who developed shivering under spinal anesthesia.On shivering, patients were randomly allocated to receive an intravenous 2 mL bolus dose of meperidine 0.4 mg/kg (meperidine group, n = 30), dexmedetomidine 0.5 µg/kg (DEX I group, n = 30), 0.3 µg/kg (DEX II group, n = 30), or 0.2µg/kg (DEX III group, n = 30). Control of shivering, time taken for cessation of shivering, response rate, recurrence, hemodynamic changes, sedation score, tympanic temperature, and side effects were noted and compared between groups. RESULTS: The groups were comparable regarding demographic profile, tympanic temperature decline, and shivering onset time (P > 0.05). Lower shivering cessation time (P < 0.001) and higher response rate (P < 0.01) were observed in DEX I and II groups compared with DEX III and meperidine groups, with a nonsignificant difference between DEX I and II groups. Recurrence of shivering activity was higher in DEX III group (36.7%, P < 0.01) compared with DEX I (10%), DEX II (6.7%) and meperidine (16.7%) groups. Lower heart rates, systolic and diastolic blood pressure mean values were recorded in DEX I group (P < 0.05). Nine patients (30%) in DEX I group were in levels 3 - 5 of sedation (P < 0.02) compared with 5 (16.66%), 2 (6.66%), and 4 (13.3) patients in DEX II, DEX III, and meperidine groups, respectively. LIMITATIONS: This study is limited by its small sample size. CONCLUSIONS: Among the 3 doses investigated, dexmedetomidine 0.3µg/kg effectively treated shivering associated with spinal anesthesia with modest hemodynamic and sedation effects. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02382432. KEY WORDS: Dexmedetomidine, hypothermia, shivering, spinal anesthesia.

Combined Intrathecal Morphine and Dexmedetomidine for Postoperative Analgesia in Patients Undergoing Major Abdominal Cancer Surgery.

OBJECTIVE: To compare the analgesic effect of combined intrathecal morphine and dexmedetomidine with either drug alone for postoperative analgesia in patients undergoing major abdominal cancer surgery. METHODS: Ninety patients were allocated to receive intrathecal 10 mg bupivacaine 0.5% (bupivacaine group, n = 30), 10 mg bupivacaine 0.5% and 0.5 mg morphine (Morphine Group, n = 30), or 10 mg bupivacaine 0.5%, 0.5 mg morphine and 5 µg dexmedetomidine (morphine-Dex group, n = 30). The groups were compared with time to first postoperative analgesia, iv patient-controlled analgesia (PCA) morphine consumption, pain scores, hemodynamics, sedation, and adverse events in the first 48h postoperative. RESULTS: The time to first use of morphine PCA was longer in morphine (22.13 ± 5.21h, P = 0.000) and morphine-Dex (23.46 ± 4.69h, P = 0.000) groups compared with bupivacaine group (0.50 ± 0.09h). Dexmedetomidine addition increased the duration of intrathecal morphine (ITM) analgesia by 1.33 h (P = 0.485). Morphine consumption was less in morphine (10.83 ± 2.96 mg, P = 0.000) and morphine-Dex (11.00 ± 3.32 mg, P = 0.000) groups than in bupivacaine group (27.5 ± 4.30 mg), with a nonsignificant difference between morphine and morphine-Dex groups (P = 0.375). Morphine and morphine-Dex groups showed lower pain scores (P < 0.001). Intraoperative blood pressure and heart rate were lower in morphine and morphine-Dex groups (P < 0.05) with no significant difference between groups in postoperative hemodynamics. Patients in bupivacaine group showed a higher incidence of postoperative nausea (P < 0.03) and vomiting (P < 0.01), while patients in morphine and morphine-Dex groups had a higher incidence of pruritus (P < 0.02). CONCLUSIONS: Our results do not support improved analgesia with the combination of intrathecal morphine and dexmedetomidine, despite the absence of significant adverse effects.

High dose intrathecal morphine for major abdominal cancer surgery: a prospective double-blind, dose-finding clinical study.

BACKGROUND: Despite 30 years of clinical research, we still do not know the optimal dose of intrathecal morphine (ITM) when used alone. OBJECTIVES: A safety investigation and comparison of the analgesic efficacy of ITM 0.2 mg, 0.5 mg, and 1 mg in patients undergoing major abdominal cancer surgery. STUDY DESIGN: A randomized, double-blind trial. SETTING: Academic medical center. METHODS: Ninety patients were randomly assigned to receive morphine intrathecally either 0.2 mg (Group I, ITM 0.2 mg, n = 30), 0.5 mg (Group II, ITM 0.5 mg, n = 30), or 1 mg (Group III, ITM 1 mg, n = 30) dissolved in 5 mL physiological saline before general anesthesia. Assessment parameters included hemodynamics, respiratory rate, peripheral arterial oxygenation, sedation score, pain severity, time of first analgesic request, total analgesic consumption, and side effects in the first 72 hours. RESULTS: The mean time to first request for rescue analgesia was significantly prolonged in Group II (22.13 ± 5.21 hours, P < 0.001) and Group III (30.83 ± 4.89 h, P < 0.001), compared with Group I (0.50 ± 0.66 hours). The mean tramadol consumption dose was significantly reduced in Group II (383.33 ± 91.28 mg, P < 0.001) and Group III (300 ± 69.48 mg, P < 0.001) compared with Group I (770 ± 114.92 mg). Patients received 1 mg ITM showed lower VAS scores in the first 48 h postoperative (P < 0.04) compared with Group I and Group II. No significant differences were observed in the mean systolic and diastolic blood pressure values, respiratory rate, and peripheral arterial oxygen saturation between groups. Lower mean heart rate values were observed in Group III patients at 6 hours (P < 0.01) and 12 hours (P < 0.03) postoperative compared with Group I and Group II patients. Six patients (20%) in Group II and 8 (26.7%) in Group III exhibited pruritus compared with 2 patients (6.66%) in Group I (P < 0.01). No intergroup statistical differences were observed for other studied side effects. LIMITATIONS: This study is limited by its small sample size. CONCLUSION: One mg ITM provided superior analgesia for 48 hours postoperative compared with 0.2 mg and 0.5 mg ITM with a nonsignificant difference in the incidence of side effects. Further studies of larger sample size are recommended to confirm these findings.

Effect of the addition of clonidine to locally administered bupivacaine on acute and chronic postmastectomy pain.

STUDY OBJECTIVES: To investigate the analgesic effect of adding clonidine to topical bupivacaine for acute and chronic postmastectomy pain. DESIGN: Randomized, prospective, double-blinded study. SETTING: Cancer institute and university hospital. PATIENTS: 140 ASA physical status 1 and II women, aged 30 to 50 years, scheduled for modified radical mastectomy with axillary dissection for breast carcinoma. INTERVENTIONS: Patients were divided into 4 groups of 35 patients each, to receive either saline 0. 9% (control group), plain bupivacaine 0.5% (Bupivacaine group), plain bupivacaine 0.5% and 150 µg of clonidine (Clonidine150 group), or plain bupivacaine 0.5% and 250 µg of clonidine (Clonidine250 group). Study drugs were irrigated into the surgical field before skin closure. MEASUREMENTS AND MAIN RESULTS: Pain severity, time to first request of rescue analgesia, analgesic consumption, hemodynamics, and side effects were recorded in the first 48 hours postoperatively. The frequency of neuropathic pain was assessed using the Douleur Neuropathique 4-question survey (DN4) in the first and second postoperative months. Mean time to first postoperative analgesic request was significantly prolonged in the Bupivacaine (5.76 ± 0.85 hrs), Clonidine150 (11.6 ± 2.38 hrs), and Clonidine250 (17.4 ± 3.27 hrs) groups compared with the control group (1.86 ± 0.65 hrs). Postoperative tramadol consumption and visual analog scores (VAS) were significantly reduced in the Bupivacaine, Clonidine150, and Clonidine250 groups. Clonidine250 group patients had the lowest VAS scores from 2 to 48 hours postoperatively. Lower mean DN4 scores (P = 0.000) and a significantly reduced frequency of neuropathic pain (P < 0.04) were recorded in the Bupivacaine, Clonidine150, and Clonidine250 groups, with a nonsignificant difference noted among the treatment groups. CONCLUSIONS: The addition of clonidine to topical bupivacaine accentuated its early postoperative analgesic efficacy.