Association between Intraoperative Hypotension and Hypertension and 30-day Postoperative Mortality in Noncardiac Surgery.

BACKGROUND: Although deviations in intraoperative blood pressure are assumed to be associated with postoperative mortality, critical blood pressure thresholds remain undefined. Therefore, the authors estimated the intraoperative thresholds of systolic blood pressure (SBP), mean blood pressure (MAP), and diastolic blood pressure (DBP) associated with increased risk-adjusted 30-day mortality. METHODS: This retrospective cohort study combined intraoperative blood pressure data from six Veterans Affairs medical centers with 30-day outcomes to determine the risk-adjusted associations between intraoperative blood pressure and 30-day mortality. Deviations in blood pressure were assessed using three methods: (1) population thresholds (individual patient sum of area under threshold [AUT] or area over threshold 2 SDs from the mean of the population intraoperative blood pressure values), (2). absolute thresholds, and (3) percent change from baseline blood pressure. RESULTS: Thirty-day mortality was associated with (1) population threshold: systolic AUT (odds ratio, 3.3; 95% CI, 2.2 to 4.8), mean AUT (2.8; 1.9 to 4.3), and diastolic AUT (2.4; 1.6 to 3.8). Approximate conversions of AUT into its separate components of pressure and time were SBP < 67 mmHg for more than 8.2 min, MAP < 49 mmHg for more than 3.9 min, DBP < 33 mmHg for more than 4.4 min. (2) Absolute threshold: SBP < 70 mmHg for more than or equal to 5 min (odds ratio, 2.9; 95% CI, 1.7 to 4.9), MAP < 49 mmHg for more than or equal to 5 min (2.4; 1.3 to 4.6), and DBP < 30 mmHg for more than or equal to 5 min (3.2; 1.8 to 5.5). (3) Percent change: MAP decreases to more than 50% from baseline for more than or equal to 5 min (2.7; 1.5 to 5.0). Intraoperative hypertension was not associated with 30-day mortality with any of these techniques. CONCLUSION: Intraoperative hypotension, but not hypertension, is associated with increased 30-day operative mortality.

A randomized, open-label study of the safety and tolerability of fospropofol for patients requiring intubation and mechanical ventilation in the intensive care unit.

BACKGROUND: Current drugs for induction and maintenance of sedation in mechanically ventilated patients in the intensive care unit have limitations. Fospropofol, a prodrug of propofol, has not been studied as a sedative in the ICU setting. METHODS: In this randomized, open-label pilot study, patients received 1 of 3 regimens with a goal of maintaining a Ramsay Sedation Score of 2 to 5: (1) fospropofol IV infusion with a bolus and increased infusion rate for agitation events (infusion/bolus); (2) fospropofol IV infusion with an increased infusion rate for agitation events (infusion only); or (3) propofol IV infusion with an increased infusion rate for agitation events. RESULTS: Sixty patients received study drug and were included in the safety and efficacy analyses. Because incidence rates for adverse events were similar between fospropofol groups, and because the study was not powered to determine significant differences between treatment groups for safety variables, adverse events for both fospropofol groups were combined. In the fospropofol groups, 28 out of 38 patients (74%) experienced treatment-emergent adverse events in comparison with 14 out of 22 patients (64%) in the propofol group. The most common treatment-emergent adverse events with fospropofol were procedural pain (21.1%) and nausea (13.2%). Two patients (1 each in the fospropofol infusion/bolus and the propofol groups) experienced hypotension during the study as a potential sedation-related adverse event. Mean plasma formate levels were not significantly different among groups. Patients in all 3 treatment groups maintained Ramsay Sedation Scores of 2 to 5 for >90% of the time they were sedated. CONCLUSION: This pilot study suggests that fospropofol, administered in either an infusion/bolus or infusion-only regimen, is tolerable and effective for short-term induction and maintenance of sedation in mechanically ventilated intensive care unit patients.

ICU sedation after coronary artery bypass graft surgery: dexmedetomidine-based versus propofol-based sedation regimens.

OBJECTIVE: To compare dexmedetomidine-based to propofol-based sedation after coronary artery bypass graft (CABG) surgery in the intensive care unit (ICU). DESIGN: Randomized, open label. SETTING: Twenty-five centers in the United States and Canada. PARTICIPANTS: Two hundred ninety-five adults undergoing CABG surgery. INTERVENTIONS: At sternal closure, patients in group A received 1.0 microg/kg of dexmedetomidine over 20 minutes and then 0.2 to 0.7 microg/kg/h to maintain a Ramsay sedation score > or =3 during assisted ventilation and > or =2 after extubation. Patients could be given propofol for additional sedation if necessary; group B patients received propofol-based care according to each investigator's standard practice. MEASUREMENTS AND MAIN RESULTS: Mean sedation levels were within target ranges in both groups. Mean times to weaning and extubation were similar, although fewer dexmedetomidine patients remained on the ventilator beyond 8 hours. Morphine use was significantly reduced in the dexmedetomidine group. Only 28% of the dexmedetomidine patients required morphine for pain relief while ventilated versus 69% of propofol-based patients (p < 0.001). Propofol patients required 4 times the mean dose of morphine while in the ICU. Mean blood pressure increased initially in both groups, then decreased to 3 mmHg below baseline in dexmedetomidine patients; mean arterial pressure remained at 9 mmHg above baseline in propofol patients. No ventricular tachycardia occurred in the dexmedetomidine-sedated patients compared with 5% of the propofol patients (p = 0.007). Respiratory rates and blood gases were similar. Fewer dexmedetomidine patients received beta-blockers (p = 0.014), antiemetics (p = 0.015), nonsteroidal anti-inflammatory drugs (p < 0.001), epinephrine (p = 0.030), or high-dose diuretics (p < 0.001). CONCLUSION: Dexmedetomidine provided safe and effective sedation for post-CABG surgical patients and significantly reduced the use of analgesics, beta-blockers, antiemetics, epinephrine, and diuretics.

Tracheoscopy with the rapiscope to verify endotracheal tube placement.

STUDY OBJECTIVE: To determine whether tracheoscopy is an accurate and quick method for verifying correct placement of the tracheal tube after intubation. DESIGN: Prospective, randomized study. SETTING: Operating rooms of a teaching hospital. PATIENTS: 26 patients scheduled for surgery and general anesthesia. INTERVENTIONS: 8.0-mm tracheal tubes were inserted into both the trachea and the esophagus. Tracheoscopy was performed consecutively through both tracheal tubes by a variety of clinicians. MEASUREMENTS: The times taken to correctly identify the trachea and the esophagus were recorded. MAIN RESULTS: Correct identification of either the esophagus or the trachea occurred with a 100% sensitivity and a 96% specificity. The mean time to recognize either the trachea or the esophagus was 22.0 seconds. CONCLUSIONS: Tracheoscopy is a reliable method for quickly verifying proper endotracheal placement of a tracheal tube.

The role of the alpha2-adrenoceptor agonist dexmedetomidine in postsurgical sedation in the intensive care unit.

Dexmedetomidine was evaluated for sedation of 401 post-surgical patients in this double-blind, randomized, placebo-controlled, multicenter trial. Dexmedetomidine or saline was started on arrival in the intensive care unit (ICU) (1.0 mcg/kg for 10 minutes), then titrated at 0.2 to 0.7 mcg/kg/h to effect. Patients could be given propofol if necessary. Morphine was administered for pain. Sixty percent of the dexmedetomidine patients required no other sedative to maintain an RSS > or = 3; 21% required < 50 mg propofol. In contrast, 76% of the control group received propofol; 59% required > or = 50 mg. Dexmedetomidine patients required significantly less morphine for pain relief (P <.001). Continuously given throughout the ICU stay, dexmedetomidine had no effect on respiratory rate, oxygen saturation, duration of weaning, or times to extubation. Nurses judged the dexmedetomidine patients were easier to manage. Later, fewer dexmedetomidine patients remembered pain or discomfort. The majority of dexmedetomidine patients maintained blood pressures within normal range, without rebound. Hypertension, atelectasis, and rigors occurred more frequently in the control group, while hypotension and bradycardia occurred more frequently in the dexmedetomidine group. Preoperative cardiovascular conditions were not risk factors for dexmedetomidine patients.