Incidence and prediction of intraoperative and postoperative cardiac arrest requiring cardiopulmonary resuscitation and 30-day mortality in non-cardiac surgical patients.

BACKGROUND: The incidence, prediction and mortality outcomes of intraoperative and postoperative cardiac arrest requiring cardiopulmonary resuscitation (CPR) in surgical patients are under investigated and have not been studied concurrently in a single study. METHODS: A retrospective cohort study was conducted using the American College of Surgeons National Surgical Quality Improvement Program data between 2008 and 2012. Firth's penalized logistic regression was used to study the incidence and identify risk factors for intra- and postoperative CPR and 30-day mortality. simplified prediction model was constructed and internally validated to predict the studied outcomes. RESULTS: Among about 1.86 million non-cardiac operations, the incidence rate of intraoperative CPR was 0.03%, and for postoperative CPR was 0.33%. The 30-day mortality incidence rate was 1.25%. The incidence rate of events decreased overtime between 2008-2012. Of the 29 potential predictors, 14 were significant for intraoperative CPR, 23 for postoperative CPR, and 25 for 30-day mortality. The five strongest predictors (highest odd ratios) of intraoperative CPR were the American Society of Anesthesiologists (ASA) physical status, Systemic Inflammatory Response Syndrome (SIRS)/sepsis, surgery type, urgent/emergency case and anesthesia technique. Intraoperative CPR, ASA, age, functional status and end stage renal disease were the most significant predictors for postoperative CPR. The most significant predictors of 30-day mortality were ASA, age, functional status, SIRS/sepsis, and disseminated cancer. The predictions with the simplified five-factor model performed well and was comparable to the full prediction model. Postoperative cardiac arrest requiring CPR, compared to intraoperative, was associated with much higher mortality. CONCLUSIONS: The incidence of cardiac arrest requiring CPR in surgical patients decreased overtime. Risk factors for intraoperative CPR, postoperative CPR and perioperative mortality are overlapped. We proposed a simplified approach compromised of five-factor model to identify patients at high risk. Postoperative, compare to intraoperative, cardiac arrest requiring CPR was associated with much higher mortality.

Dexamethasone and Clonidine, but not Epinephrine, Prolong Duration of Ropivacaine Brachial Plexus Blocks, Cross-Sectional Analysis in Outpatient Surgery Setting.

OBJECTIVE: The primary aim of this study is to determine the effect of adding dexamethasone, clonidine or both with and without epinephrine to ropivacaine and bupivacaine brachial plexus blocks. DESIGN: Observational study of prospectively collected data. SETTING: Single academic outpatient surgery center. METHODS: We evaluated 5,515 patient entries who received brachial plexus block (BPB). Multiple, rescue, unsuccessful, and distal nerve blocks of the upper extremity were excluded. The duration was calculated from the time the block was performed until the resolution of the block by patient report. Block durations were compared using Analysis of Variance. RESULTS: After exclusions, 3,706 nerve blocks were analyzed. The median concentration of ropivacaine used was 0.5%. Both clonidine and dexamethasone significantly increased block duration by 1.1 and 3.0 hours, respectively. Combining clonidine and dexamethasone with ropivacaine increased block duration by 6.2 hours (p<0.001) when compared to ropivacaine alone. Dexamethasone and Clonidine increased block duration by 5.2 hours (p<0.001) when compared to clonidine alone and by 3.2 hours (p<0.001) compared to dexamethasone alone. The addition of epinephrine to any of the adjuvants made no statistically significant difference to the duration of action except when it was added to dexamethasone. SUMMARY: For brachial plexus blocks, epinephrine did not affect the duration of analgesia when added to ropivacaine. Epinephrine did not enhance the observed increase of block duration induced by clonidine or the combination of clonidine and dexamethasone. The most block duration enhancement was observed when combination of clonidine and dexamethasone were added to ropivacaine.

Duration of upper and lower extremity peripheral nerve blockade is prolonged with dexamethasone when added to ropivacaine: a retrospective database analysis.

BACKGROUND: Dexamethasone, when added to local anesthetics, has been shown to prolong the duration of peripheral nerve blocks; however, there are limited studies utilizing large numbers of patients. The purpose of this study was to examine the effect of adding dexamethasone to ropivacaine on duration of nerve blocks of the upper and lower extremity. METHODS: We reviewed 1,040 patient records collected in an orthopedic outpatient surgery center that had received an upper or lower extremity peripheral nerve block with ropivacaine 0.5% with or without dexamethasone and/or epinephrine. The primary outcome was duration of analgesia in upper or lower extremity blocks containing dexamethasone as an adjunct. Secondary outcomes included postoperative patient pain scores, satisfaction, and the incidence of block related complications. Linear and ordinal logistic regression models were used to examine the independent effect of dexamethasone on outcomes. RESULTS: Dexamethasone was observed to increase median block duration by 37% (95% confidence interval: 31-43%). The increased block duration persisted within body regions (upper and lower) and across a range of block types. Dexamethasone was also observed to reduce pain scores on the day of surgery (P = 0.001) and postoperative day 1 (P < 0.001). There was no significant difference in duration of nerve blocks when epinephrine (1:400,000) was added to 0.5% ropivacaine with or without dexamethasone. CONCLUSION: The addition of dexamethasone to 0.5% ropivacaine prolongs the duration of peripheral nerve blocks of both the upper and lower extremity.

Successful lumbar epidural catheter placement through a lower back lipoma.

Structural abnormalities of the lumbar spine or the overlying structures may represent a relative contraindication or technical difficulty to neuraxial anesthesia. We report a case of successful epidural catheter placement through a lower back lipoma for vascular bypass surgery of the lower extremity.

The current role of ultrasound use in teaching regional anesthesia: a survey of residency programs in the United States.

BACKGROUND AND OBJECTIVES: The purpose of this survey was to determine the current teaching practices of regional anesthesia and the prevalence of ultrasound use in guiding peripheral nerve blocks in the academic institutions across the United States. METHODS: A survey was distributed to all American Board of Anesthesiology-accredited residency programs via email and/or the U.S. postal service. The survey was designed to determine the number of peripheral nerve blocks (PNBs) performed, the role of the ultrasound guidance, the barriers to its use, and the methods by which teaching physicians acquired their ultrasound skills. RESULTS: We received 82 responses (62%) of the 132 programs surveyed. Eighty-eight percent of the responding programs performed more than 20 PNBs/week and 46% performed more than 40 PNBs/week. Three-fourths of the respondents relied on ultrasound to guide the majority of single injection and continuous PNBs. When using ultrasound, most programs (79%) used real-time ultrasound without nerve stimulator. Most teaching physicians supervising ultrasound-guided PNBs received their training via workshops and/or from other colleagues. The three main reasons for using ultrasound were to 1) achieve a higher success rate; 2) improve safety; and 3) teach anesthesia trainees. However, the three main barriers to using ultrasound were 1) lack of training; 2) perceived decreased efficiency; and 3) the lack of immediate availability of equipment. Overall, ultrasound was less utilized to guide lower extremity vs upper extremity PNBs. CONCLUSIONS: Ultrasound-guided PNBs are universally taught across residency programs in the United States. Most teaching physicians believe that ultrasound increases PNB's success and improves safety of regional anesthesia. Barriers to ultrasound use are lack of faculty training and unavailability of ultrasound equipment.

Therapeutic hypothermia after exsanguination.

Therapeutic hypothermia has been shown to be effective in out-of-hospital cardiac arrest, and use of this therapy has been expanded to involve in-hospital cardiac arrest. The utility of hypothermia in cardiac arrest after hemorrhage is not known. We describe a case of successful neurological and functional outcome after in-hospital pulseless electrical activity arrest secondary to exsanguination from an internal carotid artery rupture. Therapeutic hypothermia by surface cooling was initiated after acute control of the bleeding source, restoration of circulating blood volume, and hemodynamic stabilization. We believe therapeutic hypothermia use will continue to increase for in-hospital cardiac arrests.

Teaching practices of thoracic epidural anesthesia in the United States: should lumbar epidurals be taught before thoracic epidurals?

OBJECTIVE: The purpose of this study was to determine the current teaching practice of thoracic epidural procedures in the United States and to determine the effect of the teaching sequence of thoracic and lumbar epidurals on technical difficulties and complications. DESIGN AND SETTING: The first part was a survey, which was distributed to all American Board of Anesthesiology-accredited programs. The second part was a noninterventional retrospective review of 2,007 epidural procedures in a university teaching program. INTERVENTIONS: The survey questions were designed to determine the number of epidural procedures performed monthly on various services, teaching sequence, insertion technique, indications, and service provider. RESULTS: The survey received 81 responses (60%) from 134 programs; 34% of the programs placed more thoracic than lumbar epidurals, 92% of the programs placed epidurals mainly for postoperative pain control, and 88% of programs mainly teach lumbar before thoracic epidurals, whereas only 10 programs (12%) mainly teach residents thoracic before lumbar epidurals. The authors' residents were divided into 2 groups: group 1 (42 residents, 70%) who learned thoracic before lumbar epidurals and group 2 (18 residents, 30%) who learned lumbar before thoracic epidurals during their earlier obstetric anesthesia training. There were no significant differences between the 2 groups in the degree of technical difficulties or the incidence of procedure-related complications. CONCLUSIONS: Thoracic epidurals are widely taught in the United States. Most programs teach lumbar before thoracic epidurals. Thoracic epidurals are safe to teach without prior experience with lumbar epidurals.

Management of airway obstruction caused by nasal packing material in a trauma patient.

Airway management of patients with facial trauma is challenging. This case report presents an unusual cause of partial airway obstruction by nasal packing saturated with blood clots. We stress on the importance of careful examination of the airway before instrumentation and of being aware that the distal end of the nasal packing material could migrate downward and cause airway obstruction.

Management of an unusual complication during placement of a pulmonary artery catheter.

We describe an unusual complication during flotation of a pulmonary artery catheter through a preexisting percutaneous introducer sheath. A malfunctioning pulmonary artery catheter, which was placed through an introducer sheath in the right internal jugular vein, was removed. Attempts at repositioning a second pulmonary artery catheter met with resistance, and we were unable to either advance or withdraw it. Chest radiograph showed a bent introducer sheath going from the right internal jugular vein into the right subclavian vein and a pulmonary artery catheter loop. Under continuous fluoroscopy, the introducer sheath and the pulmonary artery catheter were withdrawn as one unit, which resulted in relaxation of the acute angulation in the introducer sheath and allowed the pulmonary artery catheter to unfold, thus facilitating their complete extraction. We conclude that complications may occur during placement of a pulmonary artery catheter through a well positioned introducer sheath and that fluoroscopy is a valuable tool for safe management of such a complication.